REPRODUÇÃO ANIMAL: INSEMINAÇÃO ARTIFICIAL -/- ANIMAL BREEDING: ARTIFICIAL INSEMINATION -/- Emanuel Isaque Cordeiro da Silva Departamento de Zootecnia da UFRPE E-mail: [email protected] WhatsApp: (82)98143-8399 -/- 1. INTRODUÇÃO A inseminação artificial impôs-se em todo o mundo como um método de grande interesse do ponto de vista zootécnico e econômico, incrementando os rendimentos produtivos através da melhoria acelerada e da uniformidade no reagrupamento das populações. Os resultados positivos obtidos nestas últimas décadas testemunham esta possibilidade, válida tanto para os países mais desenvolvidos como (...) para os países em processo de desenvolvimento. A necessidade de uma rápida melhoria da estrutura das raças, o aumento da produção, bem como o máximo emprego de reprodutores selecionados difundiram consideravelmente o método da inseminação artificial, principalmente na espécie bovina, de forma que hoje se insemina artificialmente mais de 150 milhões de vacas e novilhas aptas para reprodução. Em certos países desenvolvidos, do ponto de vista pecuário, mais de 90% das vacas são inseminadas artificialmente, concretamente na Dinamarca 98%, mais de 95% no Japão e Israel ou 94% na Hungria; na Espanha chega-se a níveis muito próximos dos 50%. 2. CONCEITO E PRINCÍPIOS BÁSICOS O Larousse agrícola (1981) define a inseminação artificial como uma «técnica que consiste em depositar, no aparelho genital de uma fêmea, com a ajuda de instrumentos adequados, o sêmen de um macho colhido artificialmente». O sêmen, colhido por um processo variável e adequadamente diluído, serve para a inseminação artificial de um elevado número de fêmeas, o que permite multiplicar a capacidade reprodutiva dos machos e, portanto, constitui um poderoso meio de melhoria do gado. 3. BREVE HISTÓRIA DA INSEMINAÇÃO ARTIFICIAL Embora a zootecnia iniciasse seu verdadeiro desenvolvimento como ciência e ainda estivesse longe de abordar aspectos econômicos, Lazzaro Spallanzani no século XVIII já intuíra a extensão aplicativa da inseminação artificial realizando testes demonstrativos iniciais. Ilya Ivanov começou um século depois a aplicação prática da IA e compreendeu seu significado tecnológico. Nos primeiros anos do século XX, cientistas e técnicos tentaram desenvolver um método com profundidade; no entanto, os resultados obtidos foram escassos. As razões pelos escassos resultados podem se explicar mediante os deficientes conhecimentos da anatomia, fisiologia e patologia da reprodução e o comportamento nos dois sexos estudados, tanto do ponto de vista biológico como técnico, bem como haver trabalhado sobre espécies pouco fáceis tais como o cavalo e o cão. O conhecimento tecnológico e a aplicação sistemática da técnica tornou-se possível, em primeiro lugar, com a ideia que levou à realização da primeira vagina artificial, obra de Amantea em 1914, em seguida com a criação de eficientes mênstruos diluentes e mais recentemente com o progresso da técnica de conservação prolongada "in vitro" do material espermático por congelação. A partir dos anos trinta, em certos países como a Itália ou a Alemanha, a IA foi utilizada como meio de profilaxia das doenças genitais (brucelose, tricomoníase, vibriose, etc.). A aplicação organizada do método foi realizada pela primeira vez na Dinamarca nos anos 1938-1939, com a criação de cooperativas de inseminação com o objetivo de realizar a melhoria zootécnica bovina, alargando-se posteriormente aos outros países da Europa até à sua aplicação sistemática na atualidade. -/- 4. A PRODUÇÃO DO SÊMEN A expansão da IA na maioria das espécies de interesse zootécnico implica uma forte responsabilidade dos que se ocupam dela, tanto na fase de aplicação como na de seu desenvolvimento. No que se refere aos bovinos do Brasil, foi seguida uma ordenação coordenada das práticas de reprodução com os programas de seleção e expansão das diferentes raças. Para o efeito, foi criada uma legislação que permite dispor de normas mais completas possíveis. 4.1 Atividades a desenvolver em um centro de IA O real decreto que regula as atividades dos centros de IA (Decreto nº 91.111, de 12 de Março de 1985), que regulamenta a Lei n° 6.446, de 05 de outubro de 1977, que dispõe sobre a inspeção e fiscalização obrigatórias do sêmen destinado à inseminação artificial em animais domésticos, e dá outras providências, define como centro de IA, em seu Art. 20 Inciso 1, todo o estabelecimento que mantenha alojados reprodutores doadores de sêmen e que realize as tarefas de coleta, manipulação, Industrialização, armazenagem, comércio ou aplicação de sêmen, com as seguintes dependências: a - quarentenário; b - alojamento dos reprodutores; c - setor de coleta de sêmen; d - sala de material de coleta; e - sala de limpeza, desinfecção e esterilização de todos os materiais e instrumentos de coleta e processamento de sêmen; f - laboratório destinado ao exame, avaliação, diluição, envasamento e congelação de sêmen; g - banco de conservação de sêmen; h - setor administrativo e de expedição; i - outras dependências, se necessário. A atividade destes centros baseia-se na coleta do sêmen de reprodutores de qualidade, na sua armazenagem e subsequente distribuição; para tanto, é necessário realizar toda uma série de procedimentos para a apreciação da qualidade do sêmen e da sua aptidão para o armazenamento. A determinação da capacidade fecundante do sêmen, das suas qualidades e garantias sanitárias deve ser efetuada por técnicos especializados. 4.2 Valores genéticos do reprodutor Os centros de inseminação artificial dispõem dos melhores reprodutores de qualidade em termos de valores genéticos. De acordo com as disposições em vigor, os reprodutores devem ser submetidos a testes de descendência dos progenitores, de aptidão leiteira e estes mesmos testes ou, pelo menos, os testes de rendimento de carcaça próprio nas raças autóctones de produção de carne. Os centros devem dispor de catálogos ou listas contendo dados pormenorizados sobre a origem, qualidades reprodutivas e genéticas do reprodutor, o que permite ao criador conhecer com precisão qual é o touro (no caso dos bovinos) que lhe fornece o esperma e que melhorias pode esperar na qualidade da sua descendência. Por estas razões, os peritos dos centros devem ser responsáveis e assegurar que: a) Os reprodutores não transmitam genes letais ou semiletais ou qualquer outra anomalia geneticamente condicionada em relação à descendência. b) Os reprodutores transmitam realmente as qualidades genéticas declaradas e assegurem, em condições de manejo e alimentação dadas, uma importante produtividade da descendência. c) O preço da dose do sêmen reflita efetivamente o valor genético do reprodutor. d) O sêmen seja corretamente identificado, ou seja, pertença ao reprodutor indicado. 5. AS TÉCNICAS DE INSEMINAÇÃO ARTIFICIAL 5.1 A coleta do sêmen A coleta do sêmen constitui a primeira operação a efetuar-se na técnica da IA. Nos mamíferos domésticos existem duas formas: a) Por recolha sobre a fêmea (pós-coito). b) Por recolha sobre o macho. Para desenvolvê-las foram preconizados diversos métodos: alguns como as esponjas vaginais ou aparelhos de borracha colocados nas vias genitais da fêmea não têm mais que um interesse histórico; outros, como a criação de fístulas ou punção direta no testículo, só são úteis como métodos experimentais, inclusive existem outros métodos, porém de uso pouco frequente (eletroejaculação, amaciamento das vesículas seminais, etc.). Hoje em dia tanto para o touro, carneiro, porco, cavalo e coelho o método usual é a obtenção de sêmen a partir do macho, concretamente mediante a aplicação da técnica da vagina artificial. Nas aves a emissão do esperma obtém-se mediante a massagem manual na região abdominal dos galos reprodutores. Nas abelhas, é necessário provocar a evaginação do pênis do zangão utilizando clorofórmio para depois ser efetuada a coleta do sêmen com o auxílio de uma micropipeta. 5.1.1 O método da vagina artificial Baseia-se na utilização de um aparelho prático e simples que tenta satisfazer as condições que imitem o máximo possível o aparelho genital feminino das fêmeas no momento do coito e que permite verificar uma rápida coleta de um ejaculação livre de contaminação. -/- É essencialmente constituído por um cilindro exterior de borracha endurecida e suficientemente compacto para ser utilizado como isolante térmico. Este cilindro apresenta uma abertura com parafuso de fecho; no interior do cilindro grosseiro introduz-se outro de borracha fina e flexível (camisa) revertido em suas extremidades para mantê-lo fixo mediante umas fitas de borracha. Limitada por ambos os cilindros fica uma cavidade que só se comunica com o exterior pelo orifício praticado na parede do cilindro externo. Uma das extremidades da vagina permanece aberta e a outra ajusta-se a um tubo coletor graduado de vidro no qual se recolhe o esperma. Para simular as condições naturais, introduz-se água quente (41-42ºC em bovinos) dentro da câmara em quantidade suficiente para criar uma pressão e temperatura semelhantes à da vagina da fêmea. 6. AVALIAÇÃO E TRATAMENTO DO SÊMEN: OPERAÇÕES E TÉCNICAS No laboratório podem ser avaliadas e medidas uma série de características e propriedades do sêmen através de um controle da sua qualidade. Estes exames são conclusivos ao permitir a diluição do sêmen e a sua posterior utilização ou, se for o caso, a sua eliminação. 6.1 Estudo macroscópico do esperma 6.1.1 O volume do sêmen ejaculado O volume do esperma é muito variável segundo as espécies (Tabela 1). Mesmo dentro da mesma espécie há variações, como, por exemplo, no caso dos bovinos. Circunstâncias tais como a idade, raça, momento da coleta, método no regime sexual da mesma, época do ano, regime alimentar e grau de excitação sexual em que se encontra, provocam grandes variações no total de quantidade ejaculada por animal. Tabela 1: Características médias do sêmen dos mamíferos domésticos Espécie Volume de uma ejaculação (ml) Concentração 1099/ml N° total de spz (109) Porcentagem de spz móveis Touro 5 (1 – 12) 1,2 (0,5 – 2,5) 6 65 Carneiro 0,9 (0,1 – 0,5) 4 (1,5 – 6) 3,6 90 Porco 300 0,3 90 70 Cavalo 100 0,15 15 65 Cão 2 0,1 0,2 85 Fonte: SOLTNER, 1993. A técnica para a sua medição é imediata, é realizada após a coleta mediante a utilização de um tubo graduado. O volume total de esperma é um fator secundário de apreciação. No entanto, o interesse do seu estudo reside no fato de que o volume normal ser um índice favorável que condiciona o número de doses seminais a preparar. Além disso, outras características macroscópicas importantes do esperma são a cor e o odor característicos em cada uma delas. 6.2 Estudo microscópico do esperma 6.2.1 A motilidade massal Imediatamente após a emissão, o exame microscópico direto do esperma fresco nos permite conhecer de forma aproximada a porcentagem de espermatozoides móveis, sua morfologia, tendência dos zoospermios à aglutinação (movimento de ondas e remoinhos, já que as células vivas varrem as mortas, agrupando-as) e a presença eventual de elementos estranhos (células epiteliais, pus, partículas de terra, restos de vaselina, etc.). O método é subjetivo e serve unicamente como avaliação de conjunto; no entanto, é importante a motilidade dos espermatozoides no fluido espermático. Uma boa ejaculação não deverá conter menos de 60% de espermatozoides em movimento, e este deve ser em avanço progressivo, nunca curvo, rotatório ou oscilante. A atividade massal é avaliada tecnicamente mediante microscópio, com ligeiro aumento (20 x 40), colocando uma gota de esperma sobre uma lâmina situada numa placa de aquecimento (38-39ºC). A observação pode ser direta sobre a ocular ou pode ser facilitada por um sistema que permita a visualização num monitor de televisão. 6.2.2 A concentração zoospérmica É o número de espermatozoides por mililitro de esperma variável para as diferentes espécies (tabela 1). A determinação pode ser feita utilizando sistemas semelhantes à contagem globular utilizada em hematologia, utilizando câmaras contabilísticas especiais como a câmara Burker. Esta câmara possui uma grelha integrada por três tipos de retângulos de diferentes áreas, o que permite operar com qualquer concentração. Antes de iniciar o processo é necessário diluir o esperma para uma melhor observação colocando uma quantidade conhecida sobre a câmara sobrepondo uma lamela. A contagem consiste em anotar o número de espermatozoides cujas cabeças se encontram dentro da grade, de modo que cada dois espermatozoides que eventualmente possam apresentar sua cabeça sobreposta sobre a linha divisória se conta um. O número de quadrados sobre os quais se deve fazer a contagem é de 30, obtendo depois a média aritmética do valor que resultava do número total de espermatozoides encontrados nas 30 quadras. Um exemplo prático para conhecer a concentração de espermatozoides no gado bovino pode ser deduzida utilizando a seguinte fórmula: N = M x 400 x 10 x 200 x 1.000 Onde: N: Número de espermatozoides/mm3. M: Média dos espermatozoides contados por grade. 400: Área da grelha (1/20 x 1/20 = 1/400 mm2). 10: Altura delimitada entre a câmara e a lamela (1/19 mm). 200: Título de diluição (1/200). 1000: Conversão de mm3 para cm3. Pode-se também apreciá-lo de forma rápida e precisa usando um fotômetro, avaliando uma pequena quantidade de esperma diluído. O método é baseado na relação direta que existe entre a transparência ou densidade ante a passagem da luz através do fluido espermático e sua concentração em espermatozoides. Uma fotocélula mede a luz que atravessa a preparação, o que permite deduzir diretamente a concentração. O sistema de videomicrografia consiste em um microscópio óptico focado na amostra de sêmen (foco que é feito manualmente por meio de parafuso micrométrico), uma câmera de vídeo recolhe imagens microscópicas e estas são processadas por computador. Sua vantagem é que o sistema, totalmente automatizado, pode ser ajustado para analisar a concentração no sêmen fresco e após a descongelação do mesmo. 6.2.3 A porcentagem de espermatozoides mortos e anormais Uma das provas de aptidão genésica dos reprodutores é a determinação de formas anormais de espermatozoides. Todos os animais em que o teor de tais formas ultrapasse repetidamente um determinado limite ou que sejam de um tipo característico devem ser eliminados. As colorações específicas permitem diferenciar as formas vivas das mortas em função da aceitação dos diferentes corantes utilizados. Uma das técnicas de coloração seletiva consiste em diluir uma gota de esperma num corante vital (eosina) juntamente com nigrosina. Uma vez aplicado o corante, deixa-se secar o esfregaço ao ar de modo que a eosina cora imediatamente os zoospermios mortos no momento da mistura, enquanto a nigrosina resulta na solução de contraste. A medição pode ser feita em um hematímetro ou por colorímetro. A porcentagem de formas anormais é dada pela seguinte fórmula: x=( A x 100 )/N Onde: A: Número de espermatozoides anormais encontrados. N: Número total de espermatozoides contados. Quando o teor de espermatozoides anormais ultrapassa um certo limite ou se as malformações são de um tipo característico, considera-se a ejaculação como não válida. 6.3 Os controles biológicos e bioquímicos Os controles biológicos ao esperma e espermatozoides limitam-se a testes de resistência ou grau de vigor e a testes de sobrevivência. Os controles químicos incluem, em geral, a determinação da atividade metabólica dos espermatozoides em relação a determinados produtos: frutólise, redução do azul de metileno, consumo de oxigênio, ou a utilização de testes indicadores como GOT, DNA e acrosina. 6.4 A diluição do esperma Esse processo tem por finalidade aumentar o volume total da massa espermática. Os objetivos buscados nesse processo de diluição são: a) Partindo de uma ejaculação, o poder de inseminar o maior número possível de fêmeas. b) A criação de um meio favorável à sobrevivência dos espermatozoides "in vitro". Como diluidores são utilizados diluentes e conservantes, a maioria deles são feitos a partir de gemas de ovo, frutose, leite desnatado reconstituído ou produtos químicos como o TRIS (hidroximetilaminometano) com a adição de antibióticos e glicerol. Em qualquer caso, devem satisfazer as seguintes condições: a) Que tenha um pH idôneo para cada tipo de sêmen, com bom efeito de mistura. b) Que tenham a mesma pressão osmótica e a propriedade de mantê-la. c) Que contenham substâncias alimentares necessárias para o metabolismo dos espermatozoides. d) Que contenham os minerais necessários e na concentração adequada sem ânions nem cátions tóxicos. e) Não devem conter elementos prejudiciais para os órgãos sexuais femininos, para o processo de fecundação e o desenvolvimento do óvulo fecundado. A frutose é a principal fonte de energia para o espermatozoide; este como qualquer outra célula é capaz de metabolizar os hidratos de carbono mediante um mecanismo oxidativo anaeróbio. As proteínas do ovo regulam as variações bruscas de temperatura e certos agentes químicos e efeito conservador sobre os zoospermios, o que permite uma melhor sobrevivência dos mesmos. Os lipídeos do ovo comportam-se como fatores de proteção e os complexos lipoproteicos protegem, mas também conservam o esperma. O leite desnatado apresenta a desvantagem de uma observação mais difícil dos espermatozoides ao fazer a constatação das doses seminais. Os antibióticos têm a função de inibir o desenvolvimento dos germes que acompanham o esperma no momento da coleta. A ação mais eficaz é a penicilina e a estreptomicina. À medida que certos agentes patogênicos (vibriofetus) e outras infecções específicas são erradicados, a tendência é a diminuição na utilização de antibióticos, porque, juntamente com a sua ação positiva, implica também uma diminuição da fertilidade do sêmen. O glicerol intervém no processo de conservação e favorece a formação de cristais muito pequenos durante a congelação, o que evita o dano celular e favorece a sobrevivência dos espermatozoides. 6.4.1 A taxa de diluição É um processo importante, uma vez que é necessário assegurar os resultados da fecundação. Realizado o número de espermatozoides de cada um dos ejaculados, uma vez que têm densidade diferente, procede-se ao cálculo do volume do dilúvio-conservador necessário. O número de doses obtidas por ejaculação é muito variável. De 100 a 300 ou mais para ejaculação de touro, de 10 a 15 para o de carneiro ou de bode e de 30 a 40 para o porco. Após a diluição do esperma com o mênstruo, é requerido um período de equilíbrio para que a temperatura do sêmen desça lentamente evitando, dessa maneira, o choque térmico. 6.5 O condicionamento do esperma: o enchimento e o fechamento das palhetas Para o condicionamento dos espermatozoides, sempre que se pratique a congelação do sêmen, como é o caso dos bovinos, foram utilizados diferentes sistemas como as ampolas e os tubos de celofane. No entanto, o mais frequente no Brasil é a aplicação do método francês das palhetas, de capacidade variável (0,25 ou 0,50 ml para o sêmen de touro) e grande resistência. As palhetas devem ser previamente identificadas de acordo com os códigos estabelecidos para estes casos nos centros correspondentes onde devem recolher as chaves de número e a data do congelamento, centro, raça e reprodutor com o seu nome correspondente. As operações de marcação, enchimento e fechamento das palhetas são totalmente automatizadas, no caso dos bovinos. 6.6 A congelação do sêmen Terminada a diluição, começa o processo de conservação correta do sêmen para que conserve sua efetividade de fecundação, para isso podemos recorrer à refrigeração e à congelação. O primeiro sistema é reservado aos animais cujos espermatozoides não resistem a temperaturas baixas ou quando se procura uma inseminação imediata. Nas espécies nas quais se pode realizar a congelação, como no bovino, mesmo com o aperfeiçoamento exaustivo das técnicas atuais, existe uma porcentagem de espermatozoides mortos na operação. Para evitar o máximo possível que isso aconteça, é feita uma descida gradual da temperatura, procurando uma curva adequada, de modo a evitar os riscos acima referidos. A congelação realiza-se a —196ºC com nitrogênio líquido; a conservação neste estado é praticamente indefinida. 6.6.1 Controle após a congelação Deve ser realizada em condições de qualidade, a qual é estabelecida em função do número de espermatozoides vivos e progressivamente móveis (em bovinos nunca inferior a 35%) que apareçam uma vez descongelada a palha. Terminada a análise e estabelecidos os correspondentes controles, os centros são responsáveis por: a) A distribuição de um sêmen controlado e de qualidade. b) O sêmen após descongelação contenha um número suficiente de espermatozoides móveis e fecundantes. 6.7 A qualidade sanitária do sêmen A qualidade sanitária do sémen depende diretamente das condições de vida sanitária em que se encontra o reprodutor, das condições de coleta do sêmen, do tratamento do mesmo e da sua manipulação. A infecção do esperma pode ocorrer durante a diluição e a conservação e, mais eficazmente ainda, durante a coleta e com o ar do ambiente. A infecção pode ser causada por: a) Agentes específicos das infecções genitais, que podem propagar doenças infecciosas através da inseminação (vibriose, tricomoníase, brucelose, etc.). b) Agentes não específicos como diferentes bactérias (estafilococos, estreptococos, colibactérias, germes pirógenos, etc.), fungos (micose) e vírus (IBR) que podem provocar inflamações dos órgãos genitais da fêmea e que exercem uma influência nociva dos seus produtos de metabolismo sobre o poder fecundante dos espermatozoides. Atualmente, é possível obter esperma estéril desde que se trabalhe corretamente com os diluentes; no entanto, apesar de todas as garantias que possam oferecer a tecnologia dos centros dos diferentes países, existe uma regulamentação jurídica clara, a fim de evitar a difusão de riscos para a saúde. 7. A INSEMINAÇÃO ARTIFICIAL NA PRÁTICA No processo de inseminação propriamente dito, o sêmen é introduzido e depositado nas vias genitais da fêmea mediante o instrumental adequado. Para o seu desenvolvimento no gado bovino, são necessárias uma série de operações. 7.1 Coleta e transferência no termo de transporte As palhetas são recolhidas pelos inseminadores nos centros levando-as em pequenos contentores de transporte que contêm nitrogênio líquido. Ao retirar a palheta do recipiente é conveniente tê-la perfeitamente localizada para conseguir uma correta manipulação da cesta onde está situada, uma vez que uma queda brusca da temperatura faz diminuir a sobrevivência das células espermáticas. 7.2 A descongelação Realiza-se rapidamente num banho de água ou num termo que mantém a temperatura da água entre 35-37ºC. Outros sistemas diferentes não são recomendados, pois aumentam o tempo de descongelação e diminuem a capacidade fecundante do sêmen. 7.3 A aplicação do sêmen no aparelho genital da vaca Uma vez descongelada a palheta, seca-se e homogeneíza-se o seu conteúdo, corta-se uma das suas extremidades selada com álcool polivinílico solidificado e introduz-se no cateter de inseminação, instrumento cilíndrico no qual se introduz a palheta, posteriormente ajusta-se perfeitamente para evitar perdas de material seminal e, no momento da aplicação, o seu conteúdo é empurrado através de um sistema de êmbolo. O cateter é revestido com uma bainha de plástico, descartável após cada utilização. O método técnico que se impôs atualmente é o americano, no qual o lugar ideal para depositar o sêmen é na bifurcação dos cornos uterinos guiando-se por palpação manual através da parede retal. 7.4 O momento ideal de inseminação na vaca Há uma série de fatores que determinam o momento ideal de inseminação da vaca: a) A capacidade de sobrevivência dos espermatozoides nos órgãos sexuais femininos. b) A necessidade da maturidade dos espermatozoides (capacitação). c) O tempo de maturidade do óvulo e sua passagem pelo oviduto. Em geral, como média, as vacas permanecem no cio por 18 horas e ovulam às 14 horas depois, sendo a vida do óvulo de 6 a 10 horas. Em função destes fatores e para obter uma fertilidade ideal as vacas podem ser servidas durante os últimos dois terços do período de cio, ou algumas horas depois de este ter terminado, o que na prática se traduz em que se observa o cio pela manhã, as vacas podem ser servidas nessa mesma tarde e as que mostram o cio pela tarde são inseminadas na manhã seguinte. Em caso de dúvidas é sempre melhor deixar passar mais tempo. 7.5 Inseminação em caprinos, ovinos, suínos, equinos, coelhos, aves e abelhas Nos ovinos e caprinos, a inseminação é feita com sêmen fresco e refrigerado, normalmente conservado a 16 ºC com ampolas de ácido acético. A técnica da inseminação em si é simples, mas requer a utilização de espéculo para abrir a vulva e guiar a pistola inseminadora, injetando a dose correspondente à entrada do colo do útero. A dose seminal depositada varia entre 0,2 e 0,4 ml em concentrações de 5 x 106 espermatozoides/ml. No caso dos caprinos, a técnica é semelhante à das ovelhas, com a ressalva de que as doses seminais são geralmente, um pouco mais elevadas. Em suínos utiliza-se para inseminação o sêmen fresco, a temperatura de conservação varia entre 40 ºC e 15 ºC. As técnicas de congelação resultam na obtenção de espermatozoides móveis após a descongelação, mas com má fertilidade. Na porca o cio ou estro, momento apropriado para a inseminação, tem uma duração aproximada de 3 dias. A ovulação ocorre às 35 horas após o início do cio; este fato acontece às 30-40 horas de imobilização ante o cachaço, sendo a sobrevivência do óvulo de 12 horas. As fêmeas em cada cio podem ser inseminadas uma ou duas vezes. O momento apropriado é 24 horas após o início do estro quando se aplica uma única dose; caso se aplicarem duas, recomenda-se fazê-la de 24 à 36 horas após o aparecimento do estro. Devido à disposição peculiar do colo do útero na porca, a prática da inseminação suína requer: a) Uma deposição do sêmen intrauterina. b) Uma fixação do cateter correta para estimular as contrações uterinas e facilitar o transporte de espermatozoides. c) Evitar o refluxo do sêmen e a consequente diminuição do número de espermatozoides, o que entra em detrimento com a finalidade da fertilidade. A forma do cateter é adaptada à necessidade de uma correta fixação cervical para praticar a inseminação intrauterina de um volume importante de sêmen diluído (cerca de 100 cc). Os diversos modelos existentes, com variantes, tratam de imitar a forma do pênis do macho e introduzem-se na vagina girando para a esquerda para permitir seu deslizamento e uma boa fixação. O sêmen contido no recipiente é depositado por gravidade no útero. Nos equinos, o sêmen utilizado é fresco, normalmente a 4 ºC. A técnica apresenta uma maior dificuldade decorrente da necessidade de utilizar um longo tubo acoplado ao cateter de inseminação para o acesso fácil à zona de deposição do esperma no aparelho genital da égua. A dose correspondente é injetada a nível uterino. Nos coelhos é utilizado sêmen fresco, refrigerado e diluído. Para inseminar existem vários procedimentos, embora o mais comum seja a utilização de palhetas e pistola de inseminação. A aplicação do esperma efetua-se entre 1 e 4 horas após a coleta do mesmo. Nas aves, a técnica de inseminação é realizada com sêmen fresco extraído pouco antes da sua implantação na fêmea, uma vez que na maioria das espécies se constata uma rápida diminuição das taxas de fecundação com o tempo. O material e a metodologia do inseminador consistem em pipetas para a obtenção do esperma, dosador de sêmen diluído, palhetas descartáveis e seringas adequadas para a colocação do sêmen no aparelho genital da fêmea. Os intervalos de inseminação são, geralmente, de uma semana. Nas abelhas, a inseminação artificial das rainhas é prática corrente em centros especializados na seleção de reprodutores. A técnica requer um efeito sedativo na rainha durante a manipulação, abertura da prega da vagina e introdução da seringa na vagina. Para efetuar estas operações é necessário utilizar um aparelho especial de inseminação. 8. RESUMO E PRIMEIRAS CONCLUSÕES Aspectos como a melhoria genética, a proteção sanitária ou a organização e gestão da empresa pecuária têm sido as principais motivações para que a técnica da inseminação artificial tenha se difundido atualmente nos países com uma pecuária organizada e desenvolvida. A utilização da técnica implica na utilização de um sêmen de qualidade, garantido pelos centros de inseminação. Através de técnicas laboratoriais, é possível prever essa qualidade mediante a realização de testes macroscópicos (motilidade massal) e microscópicos (quantidade, motilidade, porcentagem de espermatozoides anormais e densidade). Constatada a sua qualidade, o sêmen é diluído com o objetivo de conservá-lo e aumentar o volume de ejaculação, sendo-lhe adicionados diferentes tipos de diluentes e aditivos. O sêmen pode ser conservado refrigerado ou congelado com nitrogênio líquido a uma temperatura negativa de -196 ºC. Para obter uma porcentagem elevada de inseminações fecundantes nos bovinos, faz-se necessário a manipulação correta das palhetas, evitando as mudanças de temperatura até à sua posterior utilização. Os processos de descongelação, secagem e colocação no cateter devem ser realizados de forma rápida e eficiente. Nas espécies em que se utiliza sêmen fresco, além de um correto desenvolvimento da técnica em si, é de vital importância a conservação do mesmo a temperatura adequada, além da sua aplicação em um curto espaço de tempo para evitar baixas taxas de fecundação. Emanuel Isaque Cordeiro da Silva – Departamento de Zootecnia da UFRPE. Recife, 2020. REFERÊNCIAS BIBLIOGRÁFICAS -/- ASBIA. Informações Técnicas sobre inseminação artificial. Acesso em: Março de 2020. ASBIA. Manual de Inseminação de Artificial, Uberaba – MG: Associação Brasileira de Inseminação Artificial, 2003. BRACKETT, B. G.; JÚNIOR, G. E. A.; SEIDEL, S. M. Avances en zootecnia. Nuevas técnicas de reproducción animal. 1ª ed. Zaragoza: Editorial Acribia, 1988. BRASIL. Legislação Informatizada - Decreto n° 91.111 de 12/03/1985. Acesso em: Março de 2020. CLÉMENT, Jean Michel. Larousse agricultural dictionary. Paris: Larousse, 1981. DERIVAUX, Jules. Fisiopatología de la reproducción e inseminación artificial de los animales domésticos. Havana: Instituto Cubano del libro, 1976. GOFFAUX, M. Quelques aspects relatives a la technologie de insémination artificielle des bovins. Elevage et insémination, n. 216, p. 5-9. 1986. HAFEZ, E. S. E. Artificial Insemination in Reproduction in Farm Animals. Lea and Febiger, Philadelphia, p. 481-497, 1990. HOPPER, Richard M. (Ed.). Bovine reproduction. New Jersey: John Wiley & Sons, 2014. HUNTER, Ronald Henry Fraser et al. Physiology and technology of reproduction in female domestic animals. Londres: Academic Press, 1980. JOHNSON, L. A.; LARSSON, K. Deep freezing of boar semen. Uppsala: Swedish University of Agricultural Sciences, 1985. LABBATE, Rodolfo D. Manual del inseminador. Córdoba: Sayg, 2000. ORGEUR, P.; SIGNORET, J. P. L'activité sexuelle du taureau: revue bibliographique. Paris: INRA, 1990, 3 (4), pp.235-242. ORTUÑO, Arturo Duarte. Manual de inseminación artificial de ganado. Disponível em: ——. Acesso em: Março de 2020. PÉREZ PÉREZ, F.; PÉREZ GUTIÉRREZ, F. Reproducción animal, inseminación animal y transplante de embriones. Barcelona: Cientifico-medica, 1985. Y PÉREZ, Félix Pérez. Reproducción e inseminación artificial ganadera. Barcelona: Cientifico-Medica, 1966. SALISBURY, G. W.; VANDERMARK, N. L. Phisiology of the reproduction and artificial insemination of cattle. San Francisco : Freeman e Company, 1961, 630 p. SEVERO, N. C. História ilustrada da inseminação artificial. São Paulo: Livre Expressão, 2013. SOLTNER, D. La reproduction des animaux domestiques d’élevage. Zootechnie générale, v. 1, Paris: Sciences et techniques agricole, 1993. (shrink)

In this eleventh book of scilogs – called in-turns and out-turns –, one may find new and old questions and solutions, referring mostly to topics on Neutrosophy, but also Multispace, with miscellaneous addition of topics on Physics, Mathematics, or Sociology – email messages to research colleagues, or replies, notes about authors, articles, or books, spontaneous ideas, and so on. -/- Exchanging ideas with Prem Kumar Singh, Feng Liu, Nicolae Bălașa, Jimmy Quellet, Minodora Rușchița, Frank Gelli, A. R. Vătuiu, Victor Christianto, (...) Vladimir I. Rogozhin, Robert Neil Boyd, Akira Kanda, Stefan Spaarmann, Oliver Consa, Yabin Shao, Junle Zhuo, Nivetha Martin, Said Broumi, Jean Dezert, Erick González, Tomasz Witczak, B. De Baets, I. Couso, D. Dubois, L. Good, Mihaela Colhon, Atiqe Ur Rahman, Muhammad Saeed, Muhammad Ihsan, Edeline Nancy, Shawkat Alkhazaleh, Shazia Rana, Vasantha Kandasamy, Santanu Acharjee, Mohamed Al-Shmrani, Parimala Manie, Mehmet Unver, Murat Olgun, Adel Aleidhri, Akira Kanda, Ilanthenral Kandasamy, Mircea Zărnescu, R. Tayebi Khorami, Arsham Borumand Saeid, Maisam Jdid, M. Abobala, Riad Hamido, Rafael Rojas, Esmaeil Zarei, Faisal Khan, Rouzbeh Abbassi, Adel Al-Odhari, Henry Garrett, Ackbar Rezaei, Saeid Jafari, Karthika Muthusamy, Harish Garg, Huda E. Khalid, Gonca D. Güngör, Muslim A. Noah Zainal, Fakhry Asad Agusfrianto, Madeleine Al-Tahan, Mariam Hariri, Yudi Mahatma, Masoud Ghods, Marco Brigliadori, Luis Enrique Aponte Pérez, Amr Mohammed, M. Aslam (in order of reference in the book). (shrink)

While social epistemologists have recently begun addressing questions about whether groups can possess beliefs or knowledge, little has yet been said about whether groups can properly be said to possess understanding. Here I want to make some progress on this question by considering two possible accounts of group understanding, modeled on accounts of group belief and knowledge: a deflationary account, according to which a group understands just in case most or all of its members understand, and an inflationary account, according (...) to which a group’s understanding does not depend solely on whether its members understand. I argue that both accounts face problems. The deflationary account has two such problems: aggregation problems that are familiar from discussions of group belief, and the problem of different bases, wherein members possess understanding for different but consistent reasons. The inflationary account faces what I call the problem of distributed grasping: while it is widely accepted that understanding requires a kind of “grasping”, it is hard to make sense of how this requirement could be met at the group level while not necessarily being met by any individual member. Despite its problems, I make a case for the inflationary account. This will require addressing the problem of distributed grasping: to do this, I propose a different way of thinking about the grasping relation at the group level, such that it is constituted by a dependency relationship between members. (shrink)

A perceptual experience of a given object seems to make the object itself present to the perceiver’s mind. Many philosophers have claimed that naïve realism (the view that to perceive is to stand in a primitive relation of acquaintance to the world) provides a better account of this phenomenological directness of perceptual experience than does the content view (the view that to perceive is to represent the world to be a certain way). But the naïve realist account of this phenomenology (...) has a conspicuous shortcoming: it explains the phenomenological directness of veridical perceptual experiences but not of hallucinations. Conversely, I maintain that a particular variety of the content view provides a unified account of the phenomenological directness of both veridical and hallucinatory experiences. If so, then contrary to what is often assumed, the phenomenological facts concerning perceptual experience are explained better by the content view than by naïve realism, and consequently, we have a compelling reason to prefer the content view to naïve realism. (shrink)

It is widely acknowledged that individual moral obligations and responsibility entail shared (or joint) moral obligations and responsibility. However, whether individual epistemic obligations and responsibility entail shared epistemic obligations and responsibility is rarely discussed. Instead, most discussions of doxastic responsibility focus on individuals considered in isolation. In contrast to this standard approach, I maintain that focusing exclusively on individuals in isolation leads to a profoundly incomplete picture of what we're epistemically obligated to do and when we deserve epistemic blame. First, (...) I argue that we have epistemic obligations to perform actions of the sort that can be performed in conjunction with other people, and that consequently, we are often jointly blameworthy when we violate shared epistemic obligations. Second, I argue that shared responsibility is especially important to doxastic responsibility thanks to the fact that we don't have the same kind of direct control over our beliefs that we have over our actions. In particular, I argue that there are many cases in which a particular individual who holds some problematic belief only deserves epistemic blame in virtue of belonging to a group all the members of which are jointly blameworthy for violating some shared epistemic obligation. (shrink)

It is well-known that naïve realism has difficulty accommodating perceptual error. Recent discussion of the issue has focused on whether the naïve realist can accommodate hallucination by adopting disjunctivism. However, illusions are more difficult for the naïve realist to explain precisely because the disjunctivist solution is not available. I discuss what I take to be the two most plausible accounts of illusion available to the naïve realist. The first claims that illusions are cases in which you are prevented from perceiving (...) properties you would ordinarily perceive and subsequently form a mistaken judgment about the perceived object. The second appeals to an unusual look or appearance that the perceived object instantiates. I argue that neither account is satisfactory and that, consequently, naïve realism ought to be rejected. (shrink)

While it is widely acknowledged that knowledge can be acquired via testimony, it has been argued that understanding cannot. While there is no consensus about what the epistemic relationship of understanding consists in, I argue here that regardless of how understanding is conceived there are kinds of understanding that can be acquired through testimony: easy understanding and easy-s understanding. I address a number of aspects of understanding that might stand in the way of being able to acquire understanding through testimony, (...) focusing on understanding ’s paradigmatic form and what it means to say that in order to understand something you need to “grasp” some information or the relationship between bits of information. I argue that in cases of both easy and easy-s understanding, no aspect of understanding stands in the way of it being able to acquire it through testimony. As a result, while not all understanding be acquired through testimony in all instances and for all subjects, this failure of acquisition is only a product of the complexity of the relevant information or one’s unfamiliarity with it, and not a product of the epistemic relationship of understanding. (shrink)

Recently, there has been growing concern that increased partisanship in news sources, as well as new ways in which people acquire information, has led to a proliferation of epistemic bubbles and echo chambers: in the former, one tends to acquire information from a limited range of sources, ones that generally support the kinds of beliefs that one already has, while the latter function in the same way, but possess the additional characteristic that certain beliefs are actively reinforced. Here I argue, (...) first, that we should conceive of epistemic bubbles and echo chambers as types of epistemically pernicious groups, and second, that while analyses of such groups have typically focused on relationships between individual members, at least part of what such groups epistemically pernicious pertains to the way that members rely on the groups themselves as sources of information. I argue that member reliance on groups results in groups being attributed a degree of credibility that outruns their warrant, a process I call groupstrapping. I argue that by recognizing the groupstrapping as an illicit method of forming and updating beliefs we can make progress on some of the open questions concerning epistemically pernicious groups. (shrink)

The fact that each of us has significantly greater confidence in the claims of co-partisans – those belonging to groups with which we identify – explains, in large part, why so many people believe a significant amount of the misinformation they encounter. It's natural to assume that such misinformed partisan beliefs typically involve a rational failure of some kind, and philosophers and psychologists have defended various accounts of the nature of the rational failure purportedly involved. I argue that none of (...) the standard diagnoses of the irrationality of misinformed partisan beliefs is convincing, but I also argue that we ought to reject attempts to characterize these beliefs as rational or consistent with epistemic virtue. Accordingly, I defend an alternative diagnosis of the relevant epistemic error. Specifically, I maintain that such beliefs typically result when an individual evaluating testimony assigns more weight to co-partisanship than he ought to under the circumstances, and consequently believes the testimony of co-partisans when better alternatives are available. (shrink)

A perennial problem in social epistemology is the problem of expert testimony, specifically expert testimony regarding scientific issues: for example, while it is important for me to know information pertaining to anthropogenic climate change, vaccine safety, Covid-19, etc., I may lack the scientific background required to determine whether the information I come across is, in fact, true. Without being able to evaluate the science itself, then, I need to find trustworthy expert testifiers to listen to. A major project in social (...) epistemology has thus become determining what the markers of trustworthiness are that laypersons can appeal to in order to identify and acquire information from expert testifiers. At the same time, the ways in which we acquire scientific information has changed significantly, with much of it nowadays being acquired in online environments. While much has been said about the potential pitfalls of seeking information online, little has been said about how the nature of seeking information online should make us think about the problem of expert testimony. Indeed, it seems to be an underlying assumption that good markers of trustworthiness apply equally well when seeking information from expert testifiers in online and offline environments alike, and that the new challenges and opportunities presented by online environments merely affects the methods by which we can acquire evidence of said trustworthiness. Here I argue that in making this assumption one risks failing to account for how unique features of the ways in which we acquire information online affect how we evaluate the trustworthiness of experts. Specifically, I argue for two main claims: first, that the nature of information-seeking online is such that the extent to which information is susceptible to manipulation is a dominant marker of trustworthiness; second, as a result, one will be more likely to seek out a particular kind of expert testifier in online environments, what I call a cooperative as opposed to preemptive expert. The result is that criteria for expert trustworthiness may look significantly different when acquiring information online as opposed to offline. (shrink)

One prominent argument for pragmatic encroachment (PE) is that PE is entailed by a combination of a principle that states that knowledge warrants proper practical reasoning, and judgments that it is more difficult to reason well when the stakes go up. I argue here that this argument is unsuccessful. One problem is that empirical tests concerning knowledge judgments in high-stakes situations only sometimes exhibit the result predicted by PE. I argue here that those judgments that appear to support PE are (...) better interpreted not as judgments that the epistemic demands for knowing increase as one’s practical situation becomes more demanding, but instead as judgments reflecting a different kind of normative epistemic evaluation, namely whether one is acting in an epistemically responsible way. The general idea is that when someone treats a proposition as a reason for acting we can evaluate them epistemically both in terms of whether they know that proposition, as well as in terms of whether they are acting on their knowledge in the right kind of way. My charge against the PE proponent, then, is that she is interpreting judgments that are indicative of whether we are adhering to certain normative epistemic requirements generally as being indicative of whether we have knowledge specifically. There are, however, normative epistemic requirements that make demands of us that are indicative of something other than our possession of knowledge. (shrink)

Thanks to the advent of social media, large numbers of Americans believe outlandish falsehoods that have been widely debunked. Many of us have a tendency to fault the individuals who hold such beliefs. We naturally assume that the individuals who form and maintain such beliefs do so in virtue of having violated some epistemic obligation: perhaps they failed to scrutinize their sources, or failed to seek out the available competing evidence. I maintain that very many ordinary individuals who acquire outlandish (...) false beliefs thanks to their use of popular social media platforms (and other similar internet technologies) deserve little or no blame for believing these falsehoods. Such individuals would be fully blameworthy only if they had formed or maintained the relevant beliefs partly in virtue of violating some epistemic obligation and had no excuse for violating that obligation. However, the nature of these internet technologies provides excuses for violating the relevant epistemic obligations, and so individuals are excused for holding the resulting false beliefs. (shrink)

ABSTRACTConventional wisdom holds that there is no lucky knowledge: if it is a matter of luck, in some relevant sense, that one's belief that p is true, then one does not know that p. Here I will argue that there is similarly no lucky understanding, at least in the case of one type of luck, namely environmental luck. This argument has three parts. First, we need to determine how we evaluate whether one has understanding, which requires determining what I will (...) call understanding's evaluative object. I argue that as the evaluative object of knowledge is a belief in a proposition, the evaluative object of understanding is a mental representation of a relational structure. Next, I show that arguments that environmental luck is incompatible with understanding miss the mark by considering cases in which one has a belief in a proposition is lucky to be true, instead of ones in which one's mental representation of a relational structure is lucky to obtain. I agree, then, with those who argue that one can have understanding when one's beliefs are environmentally lucky to be true, but that this compatibility is not relevant when considering the question of whether one can have environmentally lucky understanding. I then present what I take to be a properly constructed case which shows the incompatibility of environmental luck with understanding. (shrink)

Ascriptions of content are sensitive not only to our physical and social environment, but also to unforeseeable developments in the subsequent usage of our terms. This paper argues that the problems that may seem to come from endorsing such 'temporally sensitive' ascriptions either already follow from accepting the socially and historically sensitive ascriptions Burge and Kripke appeal to, or disappear when the view is developed in detail. If one accepts that one's society's past and current usage contributes to what one's (...) terms mean, there is little reason not to let its future usage to do so as well. (shrink)

Very often when the vast majority of experts agree on some scientific issue, laypeople nonetheless regularly consume articles, videos, lectures, etc., the principal claims of which are inconsistent with the expert consensus. Moreover, it is standardly assumed that it is entirely appropriate, and perhaps even obligatory, for laypeople to consume such anti-consensus material. I maintain that this standard assumption gets things backwards. Each of us is particularly vulnerable to false claims when we are not experts on some topic – such (...) falsehoods have systematic negative impacts on our doxastic attitudes that we can neither prevent nor correct. So, when there is clear expert consensus on a given scientific issue, while it is permissible for experts to consume anti-consensus material, laypeople have an epistemic obligation to avoid such material. This argument has important consequences for philosophical discussions of our epistemic obligations to perform or omit belief-influencing actions. Such discussions typically abstract away from the important differences between experts and laypeople. Accordingly, we should reject this typical practice as problematic, and insist instead that laypeople and experts have fundamentally different epistemic obligations. (shrink)

It is has been argued that there is a problem with moral testimony: testimony is deferential, and basing judgments and actions on deferentially acquired knowledge prevents them from having moral worth. What morality perhaps requires of us, then, is that we understand why a proposition is true, but this is something that cannot be acquired through testimony. I argue here that testimony can be both deferential as well as cooperative, and that one can acquire moral understanding through cooperative testimony. The (...) problem of moral testimony is thus not a problem with testimony generally, but a problem of deferential testimony specifically. (shrink)

The fact that you see some particular object seems to be due to the causal relation between your visual experience and that object, rather than to your experiences’ phenomenal character. On the one hand, whenever some phenomenal element of your experience stands in the right sort of causal relation to some object, your experience presents that object (your experience’s phenomenology doesn’t need to match that object). On the other hand, you can’t have a perceptual experience that presents some object unless (...) you stand in the right sort of causal relation to that object (no matter how closely your experience’s phenomenology matches some object). According to the continuity thesis, property perception is similar to object perception in these two respects. A standard reason to reject the continuity thesis is the assumption that the environmental properties that a perceptual experience presents are determined by its phenomenal properties (which are not determined by the environmental properties that cause the experience). I maintain that the continuity thesis is false but for a different reason: perceptual experiences present both objects and properties via manners of presentation; but, whereas perceptual manners of presentation for objects are purely relational, perceptual manners of presentation for properties are satisfactional. (shrink)

C.S. Peirce held what is nowadays called a “commitment view” of assertion. According to this type of view, assertion is a kind of act that is determined by its “normative effects”: by asserting a proposition one undertakes certain commitments, typically to be able to provide reason to believe what one is asserting, or, in Peirce’s words, one “takes responsibility” for the truth of the proposition one asserts. Despite being an early adopter of the view, if Peirce’s commitment view of assertion (...) is mentioned at all in contemporary discussions it is only in passing. His view is, however, far more complex and nuanced than he has been given credit for. My primary goal here, then, is to get a better understanding of Peirce’s version of a commitment view of assertion. I also argue that figuring out the details of Peirce’s theory of assertion can also provide us with a viable way to respond to problems that contemporary commitment views of assertion face. (shrink)

Recently, a number of philosophers have argued that property illusions—cases in which we perceive a property, but that property is not the property it seems to us to be in virtue of our perceptual experience—and veridical illusions—cases in which we veridically perceive an object’s properties, but our experience of some specific property is nonetheless unsuccessful or illusory—can occur. I defend the contrary view. First, I maintain that there are compelling reasons to conclude that property illusions and veridical illusions can’t occur; (...) and second, I maintain that the considerations supporting the possibility of such cases are uncompelling. (shrink)

Kripke’s Wittgenstein is standardly understood as a non-factualist about meaning ascription. Non-factualism about meaning ascription is the idea that sentences like “Joe means addition by ‘plus’” are not used to state facts about the world. Byrne and Kusch have argued that Kripke’s Wittgenstein is not a non-factualist about meaning ascription. They are aware that their interpretation is non-standard, but cite arguments from Boghossian and Wright to support their view. Boghossian argues that non-factualism about meaning ascription is incompatible with a deflationary (...) theory of truth. Wright argues that non-factualism about meaning ascription is incoherent. To support the standard interpretation, I’ll respond to each argument in turn. To the degree that my responses are successful, Byrne and Kusch have an unmotivated interpretation of Kripke’s Wittgenstein. Wilson provides a factualist interpretation that is not based on Boghossian and Wright’s arguments. Miller argues for a non-factualist interpretation against Wilson, but I’ll show that Miller’s interpretation faces a dilemma. Miller’s argument cannot be maintained if a coherent interpretation of the skeptical solution is to be provided. I’ll show how this dilemma can be avoided and provide an independent argument against Wilson so that a non-factualist interpretation of the skeptical solution can be maintained. (shrink)

Temporal externalists argue that ascriptions of thought and utterance content can legitimately reflect contingent conceptual developments that are only settled after the time of utterance. While the view has been criticized for failing to accord with our “ordinary linguistic practices”, such criticisms (1) conflate our ordinary ascriptional practices with our more general beliefs about meaning, and (2) fail to distinguish epistemically from pragmatically motivated linguistic changes. Temporal externalism relates only to the former sort of changes, and the future usage relevant (...) to what we mean reflects reason-driven practices that are rational for us to defer to. (shrink)

This paper argues that popular criticisms of semantic holism (such as that it leaves the ideas of translation, disagreement and change of mind problematic) are more properly directed at an "instability assumption" which, while often associated with holism, can be separated from it. The versions of holism that follow from 'interpretational' account of meaning are not committed to the instability assumption and can thus avoid many of the problems traditionally associated with holism.

The reports of individuals who have had their vision restored after a long period of blindness suggest that, immediately after regaining their vision, such individuals are not able to recognize shapes by vision alone. It is often assumed that the empirical literature on sight restoration tells us something important about the relationship between visual and tactile representations of shape. However, I maintain that, immediately after having their sight restored, at least some newly sighted individuals undergo visual experiences that instantiate basic (...) shape phenomenology but which do not present (that is, neither represent nor involve acquaintance with) the corresponding shape properties. Consequently, the empirical literature on sight restoration tells us something important about the role that perceptual phenomenology plays in our perceptual awareness of an object’s properties—it tells us that the properties presented by perceptual experiences are not determined by or “built into” perceptual phenomenology. In addition, I maintain that the evidence concerning sight restoration suggests an alternative theory concerning the role that sensory phenomenology plays in our perceptual awareness of an object’s properties. Specifically, it suggests that, while not inherently representational, sensory phenomenal properties can serve as vehicles for the representation of an object’s properties. (shrink)

When you have a perceptual experience of a given physical object that object seems to be immediately present to you in a way it never does when you consciously think about or imagine it. Many philosophers have claimed that naïve realism (the view that to perceive is to stand in a primitive relation of acquaintance to the world) can provide a satisfying account of this phenomenological directness of perceptual experience while the content view (the view that to perceive is to (...) represent the world to be a certain way) cannot. I argue that this claim is false. Specifically, I maintain that the only acceptable naïve realist account of the relevant phenomenology is circular and that the content view can provide a similar account. In addition, I maintain that a certain specific variety of the content view provides a non-circular and thus more satisfactory account of this phenomenology. If so, then contrary to what is commonly assumed there are powerful phenomenological grounds for preferring the content view to naïve realism. (shrink)

While the topic of assertion has recently received a fresh wave of interest from Peirce scholars, to this point no systematic account of Peirce’s view of assertion has been attempted. We think that this is a lacuna that ought to be filled. Doing so will help make better sense of Peirce’s pragmatism; further, what is hidden amongst various fragments is a robust pragmatist theory of assertion with unique characteristics that may have significant contemporary value. Here we aim to uncover this (...) theory, and to show that assertion for Peirce is not a mere corollary of pragmatic conceptions of truth, judgement, and belief, but is rather a central aspect of his philosophy. (shrink)

ABSTRACT Although in recent years Christine Ladd-Franklin has received recognition for her contributions to logic and psychology, her role in late nineteenth- and early twentieth-century philosophy, as well as her relationship with American pragmatism, has yet to be fully appreciated. My goal here is to attempt to better understand Ladd-Franklin’s place in the pragmatist tradition by drawing attention to her work on the nature and unity of the proposition. The question concerning the unity of the proposition – namely, the problem (...) of how to determine what differentiates a mere collection of terms from a unified and meaningful proposition – received substantial attention in Ladd-Franklin’s time, and would continue to interest analytic philosophers well into the twentieth century. I argue that Ladd-Franklin had a distinct theory of the proposition and solution to the problem of the unity of the proposition that she developed over the course of her writings on logic and philosophy. In spelling out her views, I will also show her work interacted with and influenced that of the pragmatist who was her greatest influence, C.S. Peirce. (shrink)

In addition to being a founder of American pragmatism, Charles Sanders Peirce was a scientist and an empiricist. A core aspect of his thoroughgoing empiricism was a mindset that treats all attitudes as revisable. His fallibilism seems to require us to constantly seek out new information, and to not be content holding any beliefs uncritically. At the same time, Peirce often states that common sense has an important role to play in both scientific and vital inquiry, and that there cannot (...) be any “direct profit in going behind common sense.” Our question is the following: alongside a scientific mindset and a commitment to the method of inquiry, where does common sense fit in? Peirce does at times directly address common sense; however, those explicit engagements are relatively infrequent. In this paper, we argue that getting a firm grip on the role of common sense in Peirce’s philosophy requires a three-pronged investigation, targeting his treatment of common sense alongside his more numerous remarks on intuition and instinct. By excavating and developing Peirce’s concepts of instinct and intuition, we show that his respect for common sense coheres with his insistence on the methodological superiority of inquiry. We conclude that Peirce shows us the way to a distinctive epistemic position balancing fallibilism and anti-scepticism, a pragmatist common sense position of considerable interest for contemporary epistemology given current interest in the relation of intuition and reason. (shrink)

If we acknowledge that a perceptual experience’s sensory phenomenology is not inherently representational, we face a puzzle. On the one hand, sensory phenomenology must play an intimate role in the perception of ordinary physical objects; but on the other hand, our experiences’ purely sensory element rarely captures our attention. I maintain that neither indirect realism nor the dual component theory provides a satisfactory solution to this puzzle: indirect realism is inconsistent with the fact that sensory phenomenology typically goes unnoticed by (...) perceivers; while, the dual component theory cannot do justice to the important role that sensory phenomenology plays in our perceptual awareness of physical objects. I argue that in order to avoid the difficulties with each of the standard alternatives, we must characterize sensory phenomenology as functioning in the way that linguistic symbols function in thought. (shrink)

Isaac Levi targets an implicit tension in C.S. Peirce’s epistemology, one that exists between the need to always be open-minded and aware of our propensity to make mistakes so that we do not “block the road of inquiry,” and the need to treat certain beliefs as infallible and to doubt only in a genuine way so that inquiry can proceed in the first place. Attempts at alleviating this tension have typically involved interpreting Peirce as ascribing different normative standards to different (...) areas of inquiry. I argue here that such “double-standard” interpretations face significant problems. I offer instead an interpretation of Peirce on which the differences between different areas of inquiry are descriptive rather than normative. Such a view resolves Levi’s tension while interpreting Peirce as consistently subscribing to one normative standard for all inquiry. (shrink)

The issue of how best to combat the negative impacts of misinformation distributed via social media hangs on the following question: are there methods that most individuals can reasonably be expected to employ that would largely protect them from the negative impact that encountering misinformation on social media would otherwise have on their beliefs? If the answer is “yes,” then presumably individuals bear significant responsibility for those negative impacts; and, further, presumably there are feasible educational remedies for the problem of (...) misinformation. However, I argue that the answer is “no.” Accordingly, I maintain that individuals do not bear significant responsibility for the negative impacts at issue; and, further, I maintain that the only effective remedies for the problem of misinformation involve changing the information environment itself. (shrink)

While engaged in the analysis of topics such as the nature of knowledge, meaning, or justice, analytic philosophers have traditionally relied extensively on their own intuitions about when the relevant terms can, and can't, be correctly applied. Consequently, if intuitions about possible cases turned out not to be a reliable tool for the proper analysis of philosophically central concepts, then a radical reworking of philosophy's (or at least analytic philosophy's) methodology would seem to be in order. It is thus not (...) surprising that the increasingly critical scrutiny that intuitions have received of late has produced what has been referred to as a "crisis" in analytic philosophy. This paper will argue, however, that at least those criticisms that stem from recent work on semantic externalism are not as serious as their proponents have claimed. Indeed, this paper will argue while the conceptual intuitions (and the analyses that result from them) will have to be recognized as fallible, they still have a prima facie claim to correctness. A naturalistic and externalistic account of concepts thus merely requires that the methodology of conceptual analysis be reinterpreted (from a 'Platonic' to a 'constructive' model) rather than given up. (shrink)

In this essay I respond to three of the most forceful objections to the open view of the future. It is argued that a) open view advocates must deny bivalence; b) the open view offers no theodicy advantages over classical theism; and c) the open view can’t assure believers that God can work all things to the better. I argue that the first objection is premised on an inadequate assessment of future tensed propositions, the second is rooted in an inadequate (...) assessment of free will, and the third is grounded in an inadequate assessment of God’s intelligence. (shrink)

Semantic holists view what one's terms mean as function of all of one's usage. Holists will thus be coherentists about semantic justification: showing that one's usage of a term is semantically justified involves showing how it coheres with the rest of one's usage. Semantic atomists, by contrast, understand semantic justification in a foundationalist fashion. Saul Kripke has, on Wittgenstein's behalf, famously argued for a type of skepticism about meaning and semantic justification. However, Kripke's argument has bite only if one understands (...) semantic justification in foundationalist terms. Consequently, Kripke's arguments lead not to a type of skepticism about meaning, but rather to the conclusion that one should be a coherentist about semantic justification, and thus a holist about semantic facts. (shrink)

'Epistemic' theories of vagueness notoriously claim that (despite the appearances to the contrary) all of our vague terms have sharp boundaries, it's just that we can't know what they are. Epistemic theories are typically criticized for failing to explain (1) the source of the ignorance postulated, and (2) how our terms could come to have such precise boundaries. Both of these objections will, however, be shown to rest on certain 'presentist' assumptions about the relation between use and meaning, and if (...) allows that the meaning constitutive elements of our linguistic practices can extend into the future, the possibility of a new sort of 'normative epistemicism' emerges. (shrink)

According to an influential variety of the representational view of perceptual experience—the singular content view—the contents of perceptual experiences include singular propositions partly composed of the particular physical object a given experience is about or of. The singular content view faces well-known difficulties accommodating hallucinations; I maintain that there is also an analogue of Frege's puzzle that poses a significant problem for this view. In fact, I believe that this puzzle presents difficulties for the theory that are unique to perception (...) in that strategies that have been developed to respond to Frege's puzzle in the case of belief cannot be employed successfully in the case of perception. Ultimately, I maintain that this perceptual analogue of Frege's puzzle provides a compelling reason to reject the singular content view of perceptual experience. (shrink)

There have been many discussions recently from philosophers, cognitive scientists, and psychologists about group polarization, with online and social media environments in particular receiving a lot of attention, both because of people's increasing reliance on such environments for receiving and exchanging information and because such environments often allow individuals to selectively interact with those who are like-minded. My goal here is to argue that the group epistemologist can facilitate understanding the kinds of factors that drive group polarization in a way (...) that has been overlooked by the existing research. Specifically, I argue that polarization can occur in part because of the ways that members of a group treat the group itself (as opposed to an individual member within that group) as a source of information, and in doing so makes their own position, as well as that of the group, more extreme. I refer to this as a structural factor in driving polarization, and argue that such factors can contribute to explanations of polarization that occurs specifically in an important subset of groups, namely online and social media groups in which little is known about other members within the group, what I refer to as anonymous, semi-anonymous and pseudonymous (ASAP) groups. (shrink)

All representationalists maintain that there is a necessary connection between an experience’s phenomenal character and intentional content; but there is a disagreement amongst representationalists regarding the nature of those intentional contents that are necessarily connected to phenomenal character. Russellian representationalists maintain that the relevant contents are composed of objects and/or properties, while Fregean representationalists maintain that the relevant contents are composed of modes of presentation of objects and properties. According to Fregean representationalists such as David Chalmers and Brad Thompson, the (...) Fregean variety of the view is preferable to the Russellian variety because the former can accommodate purported counterexamples involving spectrum inversion without illusion and colour constancy while the latter cannot. I maintain that colour constancy poses a special problem for the Fregean theory in that the features of the theory that enable it handle spectrum inversion without illusion cannot be extended to handle colour constancy. I consider the two most plausible proposals regarding how the Fregean view might be developed in order to handle colour constancy—one of which has recently been defended by Thompson —and argue that neither is adequate. I conclude that Fregean representationalism is no more able to accommodate colour constancy than is Russellian representationalism and, as such, ought to be rejected. (shrink)

The nineteenth century English Jesuit poet, Gerard Manley Hopkins struggled throughout his life with desolation over what he saw as a spiritually, intellectually and artistically unproductive life. During these periods, he experienced God’s absence in a particularly intense way. As he wrote in one sonnet, “my lament / Is cries countless, cries like dead letters sent / To dearest him that lives alas! away.” What Hopkins faced was the existential problem of suffering and hiddenness, a problem widely recognized by analytic (...) philosophers to be left relatively untouched by conceptual explanations. In this essay, I argue that Hopkins’ poems themselves fill this gap left by conceptual approaches by articulating the existential crisis faced by those who feel the searing pain of suffering and the numbing, leaden echo of silence. His lyric speaks into existential suffering in ways akin to biblical laments and, as such, creates a space in which those who suffer can meet God, even if only to contend. Understood within Hopkins’ view of the incarnation and passion, these poems also suggest a way to identify with Christ in the experience of hiddenness, thereby making God present even in divine absence. (shrink)

Early in Plato’s Republic, two cities are depicted, one healthy and one with “a fever”—the so- called luxurious city. The operative difference between these two cities is that the citizens of the latter “have surrendered themselves to the endless acquisition of money and have overstepped the limit of their necessities” (373d).i The luxury of this latter city requires the seizure of neighboring lands and consequently a standing army to defend those lands and the city’s wealth. According to the main character, (...) Socrates, war thus finds its origin in communities living beyond the natural limits of necessity. In short, the healthy or true city is sustainable, limiting its consumption to actual needs, while the luxurious city seems not to be sustainable, living beyond its needs in a perpetual quest for more. Plato spends the rest of the Republic in the attempt to reveal the political organization and virtues—in particular, the virtue of moderation—necessary for the luxurious city to be just, healthy and thereby sustainable. The contrasting images of the two cities and Plato’s subsequent discussion raise important questions about the interrelations between justice, consumption and sustainability. In this paper we appropriate Plato’s images of these metaphorical cities to discuss over-consumption and unsustainable practices by the nations of the contemporary “first world”, which in turn perpetuate poverty and environmental degradation in the nations of the “two-thirds world”. Matters of equity and justice are preeminent in our discussion. (shrink)

William James presents a preference-sensitive and future-directed notion of truth that has struck many as wildly revisionary. This paper argues that such a reaction usually results from failing to see how his accounts of truth and intentionality are intertwined. James' forward-looking account of intentionality (or "knowing") compares favorably the 'causal' and 'resemblance-driven' accounts that have been popular since his day, and it is only when his remarks about truth are placed in the context of his account of intentionality that they (...) come to seem as plausible as they manifestly did to James. (shrink)

Largely thanks to Mill’s influence, the suggestion that the state ought to restrict the distribution of misinformation will strike most philosophers as implausible. Two of Mill’s influential assumptions are particularly relevant here: first, that free speech debates should focus on moral considerations such as the harm that certain forms of expression might cause; second, that false information causes minimal harm due to the fact that human beings are psychologically well equipped to distinguish truth and falsehood. However, in addition to our (...) moral obligations, we also have a distinct set of epistemic obligations—and even when a false belief doesn’t harm anyone, it constitutes an epistemically bad outcome. Moreover, Mill was profoundly mistaken about human psychology: human beings are vulnerable to the influence of a wide variety of false claims via a wide variety of psychological mechanisms. Consequently, there is a purely epistemic justification for restricting the distribution of misinformation: because each of us has an individual epistemic obligation to avoid unnecessary exposure to misinformation, and because avoiding such exposure is simply too difficult when acting alone, we all have a shared epistemic obligation to establish laws or regulations restricting the widespread distribution of misinformation. (shrink)

Davidson has claimed that to conclude that reference is inscrutable, one must assume that "If some theory of truth... is satisfactory in the light of all relevant evidence... then any theory that is generated from the first theory by a permutation will also be satisfactory in the light of all relevant evidence." However, given that theories of truth are not directly read off the world, but rather serve as parts of larger theories of behavior, this assumption is far from self-evident. (...) A proper understanding of the role truth theories play in theories of interpretation makes the inscrutability of reference much less wide-spread than Davidson suggests, and, as a result, the radical interpretation methodology is much less likely to saddle its defenders with counterintuitive cases of indeterminacy than is commonly supposed. (shrink)

According to many theories of testimony, acts of testimony confer certain epistemic rights upon recipients, e.g., the right for the recipient to complain or otherwise hold the testifier responsible should the content of that testimony turn out to be false, and the right to “pass the epistemic buck”, such that the recipient can redirect relevant challenges they may encounter back to the testifier. While these discussions do not explicitly exclude testimonial acts that occur online, they do not specifically address them, (...) either. Here, then, I will ask the following questions: do the differences between communicating in online and offline spaces affect our testimonial epistemic rights, and if so, how? While there is no singular “online space”, here I will focus on such spaces in which users communicate with one another, and in which communicated information can be vetted by other users (for example, social media). I argue that the characteristics of online testimony should make us think about testimonial epistemic rights differently, in two ways. First, whereas such rights have traditionally been conceived of as existing between the recipient and testifier, in many different types of online communication these rights exist between the recipient and a community. This is a result of the fact that online testimony is mediated, and in some cases partially determined by, a community of users. As such, testimonial epistemic rights in online spaces may be widely extended: while the original testifier still bears the brunt of responsibility for challenges, and is the primary buck-passee, all other members of the relevant community will also bear some such responsibilities. Second, the grounds of testimonial epistemic rights may differ in online spaces. Existing theories tend to ground such rights either in assurances provided by the testifier, or else norms that govern speech acts. I argue that testimony in online spaces should cause us to look to a third option, what I call norms of information sharing. The idea is that, given the highly social nature of online communication, a recipient acquires testimonial epistemic rights in virtue of having a reasonable expectation that information that is shared and vetted by the community meets certain standards. The grounds of online testimonial epistemic rights, then, is not primarily interpersonal or norms-based, but social. (shrink)

In the distant future, a thousand years after "The Seven Days of Fire"—the holocaust that rapacious industrialization spawned—the earth is a wasteland of sterile deserts and toxic jungles that threaten the survival of the few remaining human beings. This is the world of Hayao Miyazaki's film, Nausicaä of the Valley of the Wind. In this film, Miyazaki offers a vision of an alternative to the violent quest for dominion that has brought about this environmental degradation, through the struggle of the (...) young princess of the Valley of the Wind, Nausicaä. As a messianic figure, I contend the shōjo Nausicaä offers a beneficial estrangement from common conceptions of the gospel and opens up the ecological significance of Christ's message of non-violence. Exploring the ecological and pacific aspects of the gospel through this figure, I argue, may provide a helpful lens for examining our own distorting visions in this age of war and environmental crisis. (shrink)

Take pragmatic encroachment to be the view that whether one knows that p is determined at least in part by the practical consequences surrounding the truth of p. This view represents a significant departure from the purist orthodoxy, which holds that only truth-relevant factors determine whether one knows. In this chapter I consider some consequences of accepting pragmatic encroachment when applied to problems of political knowledge and political ignorance: first, that there will be cases in which it will not be (...) practically rational to acquire political knowledge when the stakes surrounding one’s political actions are high; second, that political knowledge can be more easily acquired when one values the welfare of others less; and third, that pragmatic encroachment may fail to account for a form of epistemic injustice when it comes to evaluating the political knowledge of members of marginalized groups. I argue that while these consequences are undesirable, the extent to which the pragmatic encroacher is committed to them depends both on the details of the theory, as well as the extent to which one considers political knowledge to be important. (shrink)

In Lars von Trier’s Breaking the Waves, the protagonist Bess McNeill is often viewed as a Christ-figure, in particular, as an image of Christ’s love. In this essay, I address the feminist critique that taking Bess in this way represents a serious distortion of Christ's love, arguing that Bess need not be seen as endorsing a self-destructive and victimizing form of love that feminist critics rightly reject. Instead, I suggest that we can view her love as an indictment of the (...) institutions structuring its expression. Finally, I argue that Bess’s love for Jan combines aspects of love that have typically been segregated into eros and agape in a way that enriches our understanding of agape and prompts us in turn to re-evaluate our understanding of Christ’s love and death. (shrink)

Another paper exploring the relation between Temporal externalism and Epistemicism about Vagueness, but with slightly more emphasis on the role of constitutive norms relating to our concept of truth.

Henri Lefebvre has considerable claims to be the greatest living philosopher. His work spans some sixty years and includes original work on a diverse range of subjects, from dialectical materialism to architecture, urbanism and the experience of everyday life. The Production of Space is his major philosophical work and its translation has been long awaited by scholars in many different fields. The book is a search for a reconciliation between mental space and real space. In the course of his exploration, (...) Henri Lefebvre moves from metaphysical and ideological considerations of the meaning of space to its experience in the everyday life of home and city. He seeks, in other words, to bridge the gap between the realms of theory and practice, between the mental and the social, and between philosophy and reality. In doing so, he ranges through art, literature, architecture and economics, and further provides a powerful antidote to the sterile and obfuscatory methods and theories characteristic of much recent continental philosophy. This is a work of great vision and incisiveness. It is also characterized by its author's wit and by anecdote, as well as by a deftness of style which Donald Nicholson-Smith's sensitive translation precisely captures. (shrink)