RESUMO

The aim of this study was to investigate the relationship between age, scrotal circumference, postweaning weight and semen quality in Nellore and Caracu bulls selected for postweaning weight. Data from the andrological evaluation of 836 bulls born between 2000 and 2019, including 583 Nellore animals (Bos indicus) and 253 Caracu animals (Bos taurus), were used. The bulls were divided into categories of age at the time of assessment: category 1 consisted of animals aged 20 to 23 months (22 ± 0.76 months, 518 ± 94.17 kg), category 2 consisted of animals aged 24 to 35 months (30 ± 4.42 months, 679 ± 137.19 kg), and category 3 consisted of animals ≥ 36 months (60 ± 14.12 months, 907 ± 161.73 kg). The statistical model included the effects of breed, age category, date of semen collection, and breed x age category interaction. Heritability estimates for scrotal circumference at 13 months of age (SC1year) and semen quality traits were obtained for the sample of Nellore animals. Most semen quality traits improved with increasing age in both Nellore and Caracu animals. High heritability was observed for SC1year (0.45), while sperm motility, vigor, turbulence, and major, minor and total sperm defects exhibited low heritability (0.11, 0.019, 0.047, 0.017, 0.017 and 0.019, respectively). Spearman correlations of breeding values for postweaning weight (W378) and SC1year with the semen quality traits were low. Nellore and Caracu bulls have similar semen quality that improves with increasing age. In the Nellore breed, the heritability of SC is high, while semen quality traits exhibit low heritability. Selection for higher postweaning weight does not phenotypically affect the semen quality of bulls at breeding age.

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Na prática, compreender a anatomia reprodutiva, a fisiologia e o comportamento do macho, da espécie selvagem com a qual se está trabalhando, é essencial para a avaliação andrológica e para a reprodução bem sucedida. Neste artigo damos especial ênfase à andrologia de felídeos selvagens. O profissional pode ser chamado para solucionar problemas quando a espécie apresenta dificuldade de reprodução em cativeiro e/ou encontra-se ameaçada de extinção. Baixas taxas de fertilidade e de prenhez podem estar associadas ao macho, com influências do estresse pelo cativeiro, nutrição inadequada e erros de manejo reprodutivo. E também, as instituições que mantêm essas espécies sob cuidado humano poderão ser auxiliadas no manejo reprodutivo com o exame andrológico periódico, que pode ser acompanhado de criopreservação de sêmen para formação ou manutenção de um banco de reserva genômica. Como componente de um programa holístico de conservação, incluindo os estudos de ecologia de campo, esta estratégia fortalece ainda mais o vínculo entre as populações ex situ e in situ.(AU)

In practice, understanding the male reproductive anatomy, physiology and the behavior, of the wild species that you are working, is essential for andrological assessment and successful reproduction. In this article we give special emphasis to the andrology of wild felids. The professional can be called to solve problems when the species has difficulty reproducing in captivity and/or is threatened with extinction. Low fertility and pregnancy rates may be associated with the male, with influences from stress in captivity, inadequate nutrition and reproductive management errors. Also, the institutions that keep these species under human care can be assisted in reproductive management with periodic andrological examination, which can be accompanied by semen cryopreservation for the formation or maintenance of a genome resource bank. As a component of a holistic conservation program, including field ecology studies, this strategy further strengthens the link between ex situ and in situ populations.(AU)

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O exame clínico andrológico é a ferramenta de eleição utilizada para avaliar a fertilidade de um reprodutor. Normalmente utilizado em tourinhos jovens na pré-comercialização, como uma forma de garantia reprodutiva; no período pré-estação de monta; quando existem falhas ou desordens reprodutivas nos rebanhos; prévio ao ingresso nas centrais de inseminação; na determinação da puberdade, dentre outras. O exame clínico andrológico deve ser realizado por profissional com experiência suficiente para tomada de decisões sobre o real potencial reprodutivo dos animais, porém, em muitas ocasiões mesmo um profissional capacitado defronta-se com dúvidas, entre elas destacam-se as questões relacionadas ao valor cobrado e "tipo de exame"; a biometria testicular; exigências relacionadas a impotencia coeundi; e o que é necessário no certificado do exame. Buscou-se elencar, explanar e discutir essas questões em vista de diminuí-las e/ou encontrar possíveis soluções. O exame clínico andrológico é uma etapa fundamental e complexa para a seleção de reprodutores, e apesar de constantemente debatida, ainda permanecem lacunas a serem respondidas, visto que os profissionais necessitam de constante atualização.(AU)

The clinical andrological examination is the tool of choice used to assess the fertility of a sire. Usually used in young bulls in pre-marketing, as a form of reproductive guarantee; in the pre-mounting season period; when there are reproductive failures/disorders in herds; before entering insemination centers, in determining puberty, among others. The clinical andrological examination must be carried out by a professional with sufficient expertise to make decisions about the real reproductive potential of these animals, however, on many occasions even a trained professional is faced with doubts, among them the issues related to the amount charged and "type of exam"; testicular biometry; requirements related to impotencia coeundi; and what is required in the exam certificate. Based on the above context, we sought to list some possible doubts, explaining them and discussing them among veterinarians, so that such issues could be reduced and/or possible alternative solutions could be defined. The clinical andrological examination is a fundamental and complex step for the selection of sires, and despite being constantly debated, there are still gaps to be answered, since professionals need constant updating.(AU)

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The goal of this study was to evaluate the rejection rates of Zebu bulls during behavioral assessment (libido and serving ability) and the importance of this step in bull breeding soundness evaluation (BBSE). A totalof 1,534 bulls reared in the state of Rio Grande do Sul, Brazil, of Nelore (1,340), Brahman (76), Guzerá (98), and Tabapuã (210) breeds were evaluated. The evaluation consisted of four steps. Step I was the general physical examination, Step II genital tract examination, Step III semen evaluation, and Step IV behavioral assessment of libido and the ability to complete copulation. To evaluate the relationship between the binary variables of approved or rejected during different steps of the BBSE, and age groups (young and mature bulls), chi-square tests and logistic regression were used. The general rejection rates in the BBSE were 5.64% and 15.20% for young and mature Zebu bulls, respectively. Problems with the sexual behavior (libido and/or serving ability) of bulls accounted for the rejection of 0.46% and 2.29% of young and mature Zebubulls, respectively. The lack of libido and serving ability was shown to be an important problem concerning the total number of possible causes of Zebu bull rejection during the BBSE. This result suggests that the behavioral step should be performed regularly, rather than being complementary to the standard BBSE in Zebu cattle.

O objetivo deste estudo foi avaliar as taxas de reprovação de touros zebuínos durante a avaliação comportamental (libido e habilidade física) e a importância desta etapa no Exame Andrológico em Touros (EAT). Foram avaliados 1.534 touros, criados no estado do Rio Grande do Sul, Brasil, das raças Nelore(1.340), Brahman (76), Guzerá (98) e Tabapuã (210). A avaliação constou de quatro etapas. Etapa I foi o exame físico geral, Etapa II o exame do trato genital, Etapa III a avaliação do sêmen, e a Etapa IV a avaliação comportamental de libido e habilidade física para completar a cópula. Para avaliar a relação entre a variável binária aprovado ou reprovado durante as diferentes etapas do exame andrológico e as faixas etárias (touros jovens e adultos), foram utilizados os testes de qui-quadrado e de regressão logística. As taxas gerais de reprovação no EAT foram de 5,64% e 15,20% para os touros Zebu jovens e adultos, respectivamente. Problemas no comportamento sexual (libido e/ou habilidade física) dos touros foram responsáveis pela reprovação de 0,46% e 2,29% dos touros zebuínos jovens e adultos, respectivamente. A falta de libido e de habilidade física mostrou-se um problema importante em relação ao número total de possíveis causas de reprovação de touros zebuínos no EAT. Esse resultado sugere que a etapa comportamental deve ser realizada regularmente, ao invés de ser apenas complementar ao EAT padrão em bovinos zebuínos.

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RESUMO

The goal of this study was to evaluate the rejection rates of Zebu bulls during behavioral assessment (libido and serving ability) and the importance of this step in bull breeding soundness evaluation (BBSE). A totalof 1,534 bulls reared in the state of Rio Grande do Sul, Brazil, of Nelore (1,340), Brahman (76), Guzerá (98), and Tabapuã (210) breeds were evaluated. The evaluation consisted of four steps. Step I was the general physical examination, Step II genital tract examination, Step III semen evaluation, and Step IV behavioral assessment of libido and the ability to complete copulation. To evaluate the relationship between the binary variables of approved or rejected during different steps of the BBSE, and age groups (young and mature bulls), chi-square tests and logistic regression were used. The general rejection rates in the BBSE were 5.64% and 15.20% for young and mature Zebu bulls, respectively. Problems with the sexual behavior (libido and/or serving ability) of bulls accounted for the rejection of 0.46% and 2.29% of young and mature Zebubulls, respectively. The lack of libido and serving ability was shown to be an important problem concerning the total number of possible causes of Zebu bull rejection during the BBSE. This result suggests that the behavioral step should be performed regularly, rather than being complementary to the standard BBSE in Zebu cattle.(AU)

O objetivo deste estudo foi avaliar as taxas de reprovação de touros zebuínos durante a avaliação comportamental (libido e habilidade física) e a importância desta etapa no Exame Andrológico em Touros (EAT). Foram avaliados 1.534 touros, criados no estado do Rio Grande do Sul, Brasil, das raças Nelore(1.340), Brahman (76), Guzerá (98) e Tabapuã (210). A avaliação constou de quatro etapas. Etapa I foi o exame físico geral, Etapa II o exame do trato genital, Etapa III a avaliação do sêmen, e a Etapa IV a avaliação comportamental de libido e habilidade física para completar a cópula. Para avaliar a relação entre a variável binária aprovado ou reprovado durante as diferentes etapas do exame andrológico e as faixas etárias (touros jovens e adultos), foram utilizados os testes de qui-quadrado e de regressão logística. As taxas gerais de reprovação no EAT foram de 5,64% e 15,20% para os touros Zebu jovens e adultos, respectivamente. Problemas no comportamento sexual (libido e/ou habilidade física) dos touros foram responsáveis pela reprovação de 0,46% e 2,29% dos touros zebuínos jovens e adultos, respectivamente. A falta de libido e de habilidade física mostrou-se um problema importante em relação ao número total de possíveis causas de reprovação de touros zebuínos no EAT. Esse resultado sugere que a etapa comportamental deve ser realizada regularmente, ao invés de ser apenas complementar ao EAT padrão em bovinos zebuínos.(AU)

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O objetivo do estudo foi avaliar perímetro escrotal e características seminais de touros da raça Senepol, de acordo com a idade e as correlações entre elas. Foram avaliados 397 touros na raça Senepol, com idade entre 12 e 30 meses, puros de origem, do estado de Minas Gerais. O método de coleta foi massagem das ampolas e eletroejaculação. Foram avaliados motilidade e vigor do sêmen e os defeitos espermáticos. Os dados foram analisados pelo teste de Kruskal-Wallis e pelo método de Spearman. Os testículos apresentaram um crescimento linear com a idade. Houve maior diferença na motilidade espermática em animais com 18 e 20 meses de idade e o vigor espermático apresentou maior diferença em animais com 20 meses. Houve correlação significativa entre todas as características analisadas. O perímetro escrotal em touros Senepol apresentou crescimento linear dos 12 aos 30 meses e mesmo os animais mais jovens, com menor perímetro escrotal, já apresentaram boa qualidade de sêmen, o que mostra a precocidade reprodutiva dos machos dessa raça. Conclui-se que o perímetro escrotal em touros Senepol apresenta crescimento linear dos 12 aos 30 meses e mesmo os animais mais jovens, já apresentam boa qualidade de sêmen, indicando uma precocidade reprodutiva dos machos dessa raça.(AU)

The objective of this study was evaluate scrotal perimeter and seminal characteteristics of Senepol bulls acording to age and correlations between them. 397 Senepol bulls were avaliable, with ages between 12 and 30 months, pure breed, in the state of Minas Gerais. The collect method were massage of ampoules and electro-ejaculation. Motility and vigor of semen and sperm defects were avaliable. Data were analyzed by the Kruskal-Wallis test and the Spearman method. The tests had a linear growth with age. The biggest difference of motility were in animals with 18 and 20 months of age and the biggest difference of vigor were in animals with 20 months. There was a significant correlation between all analyzed characteristics. Concludes that the scrotal perimeter in Senepol bulls have a linear growth from 12 to 30 months and even the youngest animals, it is a already a good semen quality, indicating a reproductive precocity in males of this breed.(AU)

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RESUMO

O objetivo do estudo foi avaliar perímetro escrotal e características seminais de touros da raça Senepol, de acordo com a idade e as correlações entre elas. Foram avaliados 397 touros na raça Senepol, com idade entre 12 e 30 meses, puros de origem, do estado de Minas Gerais. O método de coleta foi massagem das ampolas e eletroejaculação. Foram avaliados motilidade e vigor do sêmen e os defeitos espermáticos. Os dados foram analisados pelo teste de Kruskal-Wallis e pelo método de Spearman. Os testículos apresentaram um crescimento linear com a idade. Houve maior diferença na motilidade espermática em animais com 18 e 20 meses de idade e o vigor espermático apresentou maior diferença em animais com 20 meses. Houve correlação significativa entre todas as características analisadas. O perímetro escrotal em touros Senepol apresentou crescimento linear dos 12 aos 30 meses e mesmo os animais mais jovens, com menor perímetro escrotal, já apresentaram boa qualidade de sêmen, o que mostra a precocidade reprodutiva dos machos dessa raça. Conclui-se que o perímetro escrotal em touros Senepol apresenta crescimento linear dos 12 aos 30 meses e mesmo os animais mais jovens, já apresentam boa qualidade de sêmen, indicando uma precocidade reprodutiva dos machos dessa raça.

The objective of this study was evaluate scrotal perimeter and seminal characteteristics of Senepol bulls acording to age and correlations between them. 397 Senepol bulls were avaliable, with ages between 12 and 30 months, pure breed, in the state of Minas Gerais. The collect method were massage of ampoules and electro-ejaculation. Motility and vigor of semen and sperm defects were avaliable. Data were analyzed by the Kruskal-Wallis test and the Spearman method. The tests had a linear growth with age. The biggest difference of motility were in animals with 18 and 20 months of age and the biggest difference of vigor were in animals with 20 months. There was a significant correlation between all analyzed characteristics. Concludes that the scrotal perimeter in Senepol bulls have a linear growth from 12 to 30 months and even the youngest animals, it is a already a good semen quality, indicating a reproductive precocity in males of this breed.

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La presente investigación se planteó con el objetivo de determinar el estado de madurez sexual de toros jóvenes de la raza nelore y su relación con el perímetro escrotal y las características seminales. Se estudiaron 1985 animales con edades comprendidas entre los 19 y los 23 meses de edad, alimentados con pasturas tropicales (Brachiaria brizantha, Brachiaria decumbes y Panicum maximun) y evaluados a través de examen andrológico. Se valoraron las características físicas del eyaculado, la morfología espermática y el perímetro escrotal (PE). Tras el examen andrológico, los animales se clasificaron como aptos para la reproducción (clase andrológica 1); aptos para la reproducción en régimen de monta natural (clase 2); no aptos para la reproducción temporalmente (clase 3) y descartados (clase 5). Para comparar las medias encontradas entre las clases andrológicas se utilizaron dos pruebas: la de Tukey, con probabilidad del 5 % de error, y la de correlaciones simples de Pearson, para verificar las relaciones entre las características estudiadas. Se encontró que el 84,5 % de los toros son sexualmente maduros. El 39,75 % de los animales aptos para la reproducción presentó un PE mayor a 34 cm, y solo el 0,71 % de la población estudiada exhibió una circunferencia escrotal inferior a 28 cm. Se registraron correlaciones altas favorables entre PE y las características físicas del semen. Se concluye que el PE es una excelente característica para evaluar y seleccionar toros jóvenes de la raza nelore.

This research aimed to determine the state of sexual maturity of young Nelore bulls and its relation to scrotal circumference and seminal characteristics. 1985 animals (aged between 19 and 23 months), fed with tropical pastures (Brachiaria brizantha, Brachiaria decumbes, and Panicum maximum), were evaluated through andrological examination. Physical characteristics of the ejaculate, sperm morphology and scrotal circumference (SC) were examined. After the andrological examination, animals were classified as suitable for reproduction (andrological class 1); suitable for reproduction in natural mating system (class 2); temporarily unsuitable for reproduction (class 3); and discarded (class 5). To compare the measurements found in different andrological classes, two tests were used: the Tukey test with 5% probability of error, and simple Pearson correlations to verify the relationships between the studied characteristics. 84.5% of the bulls were found to be sexually mature. 39.75% of the animals suitable for reproduction presented a SC greater than 34 cm, and only 0.71% of the study population showed a scrotal circumference less than 28 cm. Favorable high correlations between SC and the physical characteristics of semen were evidenced. The article concludes that scrotal circumference is an excellent characteristics for evaluating and selecting young Nelore bulls.

Esta pesquisa foi proposta com o objetivo de determinar o estado de maturidade sexual de touros jovens da raça nelore e sua relação com o perímetro escrotal e as características seminais. Realizou-se um estudo com 1985 animais com idades compreendidas entre os 19 e os 23 meses de idade, alimentados com pastagens tropicais (Brachiaria brizantha, Brachiaria decumbes e Panicum maximun) e avaliados através de exame andrológico. Avaliaram-se as características físicas do ejaculado, a morfologia espermática e o perímetro escrotal (PE). Depois do exame andrológico, os animais se classificaram como aptos para a reprodução (tipo andrológica 1); aptos para a reprodução em regime de monta natural (tipo 2); não aptos para a reprodução temporariamente (tipo 3) e descartados (tipo 5). Para comparar as médias encontradas entre os tipos andrológicos se utilizaram dois testes: o de Tukey, com probabilidade de 5 % de erro, e a de correlações simples de Pearson, para verificar as relações entre as características estudadas. Encontrou-se que o 84,5 % dos touros são sexualmente maduros. O 39,75 % dos animais aptos para a reprodução apresentou um PE superior a 34 cm, e somente o 0,71 % da população estudada exibiu uma circunferência escrotal inferior a 28 cm. Registraram-se correlações altas favoráveis entre PE e as características físicas do sêmen. Conclui-se que o PE é uma excelente característica para avaliar e selecionar touros jovens da raça nelore.

RESUMO

Estudou-se o perfil de proteínas totais (PLB) e proteínas ligadoras de heparina (PLH) do plasma seminal de touros da raça Gir e suas associações com parâmetros andrológicos e fertilidade in vitro. A concentração da PLB variou de 4,1 a 167,9 mg/mL e da PLH entre 0,02096 e 0,19025 (%). O perfil cromatográfico apresentou nove picos de afinidade para PLB e cinco picos para PLH. As associações significativas foram: PLB x taxa de blastocistos, PLH do pico 1 x taxa de blastocistos, PLH do pico 5 x taxa de clivagem e blastocistos. Nenhuma proteína estudada apresentou associação com parâmetros andrológicos. (AU)

It was studied the seminal plasma total protein (TP) and heparin binding protein (PLH) profiles of Gyr bulls and their associations with andrological parameters and in vitro fertility. Total protein concentration varied between 4,1 a 167,9 mg/ml and heparin binding protein 0,02096 to 0,19025 (%). Chromatographic profile of TP presented nine peaks. PLH presented five affinity peaks. Associations were for: total proteins x blastocysts rate, peak 1 heparin binding proteins x blastocysts rate, peak 5 heparin binding protein x cleavage rate and blastocysts rate. However no protein showed association with andrological parameters. (AU)

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Estudou-se o perfil de proteínas totais (PLB) e proteínas ligadoras de heparina (PLH) do plasma seminal de touros da raça Gir e suas associações com parâmetros andrológicos e fertilidade in vitro. A concentração da PLB variou de 4,1 a 167,9 mg/mL e da PLH entre 0,02096 e 0,19025 (%). O perfil cromatográfico apresentou nove picos de afinidade para PLB e cinco picos para PLH. As associações significativas foram: PLB x taxa de blastocistos, PLH do pico 1 x taxa de blastocistos, PLH do pico 5 x taxa de clivagem e blastocistos. Nenhuma proteína estudada apresentou associação com parâmetros andrológicos.

It was studied the seminal plasma total protein (TP) and heparin binding protein (PLH) profiles of Gyr bulls and their associations with andrological parameters and in vitro fertility. Total protein concentration varied between 4,1 a 167,9 mg/ml and heparin binding protein 0,02096 to 0,19025 (%). Chromatographic profile of TP presented nine peaks. PLH presented five affinity peaks. Associations were for: total proteins x blastocysts rate, peak 1 heparin binding proteins x blastocysts rate, peak 5 heparin binding protein x cleavage rate and blastocysts rate. However no protein showed association with andrological parameters.

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This study evaluated the semen quality of Santa Ines sheep fed diets containing different levels of whole cottonseed (WCS). Twenty sheep were distributed into four groups that were given diets with 0; 20; 30; 40% of WCS. For this study the semen was collected by electroejaculation, and a monthly andrological examination was performed during nine months. The analyzed variables were: scrotal circumference (SC), appearance and color of the ejaculate, progressive motility (PM), vigor, mass movement (MM), total sperm concentration (spzX109), sperm morphology (SM) and blood hematocrit. The SC had no difference among diets, with mean 31.83 cm. The animals fed diets with WCS, presented mean intake of 9.16 mg gossypol kg BW, and were prone to present greenish semen, and appearance ranging from thin creamy to watery. The PM decreased linearly (p 0.05) with increasing level of WCS, while the vigor had a quadratic trend. The total defects increased linearly in relation to reference values described in literature. The WSC had no influence on hematocrit levels, but did affect the PM and vigor of spermatozoa, thus not recommended to diets of animals for breeding.

RESUMO

This study evaluated the semen quality of Santa Ines sheep fed diets containing different levels of whole cottonseed (WCS). Twenty sheep were distributed into four groups that were given diets with 0; 20; 30; 40% of WCS. For this study the semen was collected by electroejaculation, and a monthly andrological examination was performed during nine months. The analyzed variables were: scrotal circumference (SC), appearance and color of the ejaculate, progressive motility (PM), vigor, mass movement (MM), total sperm concentration (spzX109 ), sperm morphology (SM) and blood hematocrit. The SC had no difference among diets, with mean 31.83 cm. The animals fed diets with WCS, presented mean intake of 9.16 mg gossypol kg BW, and were prone to present greenish semen, and appearance ranging from thin creamy to watery. The PM decreased linearly (p < 0.05) with increasing level of WCS, while the vigor had a quadratic trend. The total defects increased linearly in relation to reference values described in literature. The WSC had no influence on hematocrit levels, but did affect the PM and vigor of spermatozoa, thus not recommended to diets of animals for breeding.

Este estudo objetivou avaliar a qualidade do sêmen de carneiros da raça Santa Inês, alimentados com dietas contendo diferentes níveis de caroço de algodão integral (CAI). Foram utilizados 20 carneiros distribuídos em quatro dietas e alimentados com 0, 20, 30, 40% do caroço de algodão integral. Para este estudo realizou-se a coleta de sêmen dos animais pelo método da eletroejaculação e durante nove meses procedeu-se o exame andrológico mensal. As variáveis analisadas foram: circunferência escrotal (CE); volume, aspecto e cor do ejaculado, motilidade progressiva (MP), vigor, movimento de massa (MM), concentração espermática total (spzX109 ), morfologia espermática (ME) e hematócritos sanguíneos. A CE não variou entre as dietas com média de 31,83 cm. Os animais que receberam (CAI) tiveram ingestão média de 9,16 mg de gossipol kg-1 PV, e tenderam a apresentar o sêmen de coloração esverdeada, com aspecto variando de cremoso fino a aquoso. Nas características microscópicas a MP decresceu linearmente com aumento do nível de CAI, enquanto o vigor mostrou comportamento quadrático. Os defeitos totais tiveram efeito linear crescente em relação aos valores de referência descritos na literatura. O CAI não influenciou os níveis de hematócritos, porém afetou a motilidade progressiva e o vigor dos espermatozoides, não devendo ser usado em dietas de animais destinados à reprodução.

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RESUMO

This study evaluated the semen quality of Santa Ines sheep fed diets containing different levels of whole cottonseed (WCS). Twenty sheep were distributed into four groups that were given diets with 0; 20; 30; 40% of WCS. For this study the semen was collected by electroejaculation, and a monthly andrological examination was performed during nine months. The analyzed variables were: scrotal circumference (SC), appearance and color of the ejaculate, progressive motility (PM), vigor, mass movement (MM), total sperm concentration (spzX109), sperm morphology (SM) and blood hematocrit. The SC had no difference among diets, with mean 31.83 cm. The animals fed diets with WCS, presented mean intake of 9.16 mg gossypol kg BW, and were prone to present greenish semen, and appearance ranging from thin creamy to watery. The PM decreased linearly (p 0.05) with increasing level of WCS, while the vigor had a quadratic trend. The total defects increased linearly in relation to reference values described in literature. The WSC had no influence on hematocrit levels, but did affect the PM and vigor of spermatozoa, thus not recommended to diets of animals for breeding.

RESUMO

The importance of the breeding soundness evaluation to improve the fertility of herds is described. With a cattle density of 205 million head, beef cattle in Brazil presents great economic importance, being the largest exporter and second largest producer of meat. This quantitative focus does not represent the reality on the productivity of herds, with observed rates low production and reproductive performance. The breeding soundness evaluation as a routine reproductive management, assumes an important role to aid to the selection of animals with normal genital systems, improving the fertility of the herd and contributes directly for diagnosis of reproductive diseases and condition of sexual and reproductive maturity of the bulls. The identification of markers of fertility in the semen with rapid tests, can contribute to the selection of bulls with better reproductive potential.(AU)

Assuntos

RESUMO

The importance of the breeding soundness evaluation to improve the fertility of herds is described. With a cattle density of 205 million head, beef cattle in Brazil presents great economic importance, being the largest exporter and second largest producer of meat. This quantitative focus does not represent the reality on the productivity of herds, with observed rates low production and reproductive performance. The breeding soundness evaluation as a routine reproductive management, assumes an important role to aid to the selection of animals with normal genital systems, improving the fertility of the herd and contributes directly for diagnosis of reproductive diseases and condition of sexual and reproductive maturity of the bulls. The identification of markers of fertility in the semen with rapid tests, can contribute to the selection of bulls with better reproductive potential.

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RESUMO

Determinaram-se as características andrológicas de touros da raça Gir, classificando-os quanto ao seu potencial reprodutivo, utilizando-se o sistema de classificação andrológica por pontos (CAP). Os animais foram separados em três grupos: G1= animais de 18-24 meses (n=33), G2 = 25-31 meses (n=24) e G3 = 32-38 meses (n=12). A média da circunferência escrotal no G1 foi menor (P<0,05) do que nos G2 e G3. A motilidade (%) e o vigor não diferiram entre os grupos. As taxas (%) de defeitos maiores e totais foram maiores (P<0,05) no G1 do que nos G2 e G3. Para as características andrológicas não houve diferenças entre G2 e G3. Com relação ao CAP, G1, G2 e G3 apresentaram, respectivamente, 25,7%, 58,3% e 61,5% de animais aptos à reprodução; 11,4%, 20,8% e 15,4% questionáveis e 57,1%, 12,5% e 15,4% inaptos ou imaturos. A idade dos touros Gir influenciou a circunferência escrotal e os defeitos maiores e totais, mas não a motilidade e o vigor. Maior proporção de animais aptos à reprodução ocorreu após 24 meses de idade.(AU)

Gyr bulls were ranked regarding their reproductive potential, following evaluations through the score-based andrological classification system (ACP). For the examinations, three animal age groups were considered: 18 to 24 month-old (G1, n=33), 25 to 31 month-old (G2, n=24), and 32 to 38 month-old (G3, n=12). Scrotal circumference was lower in G1, as compared to G2 and G3 (P<0.05). Percent motility and vigor were not affected by the age groups. Percent rates of major and total defects were higher (P<0.05) in G1 than in G2 or G3. No significant differences were observed when G2 and G3 were compared. Regarding ACP data, G1, G2 and G3 yielded, respectively, 25.7, 58.3 and 61.5% of adequate breeders; 11.4, 20.8 and 15.4% of bulls with undefined breeding capacity, and 57.1, 12.5 and 15.4% of inapt breeders or immature animals. Age group affected scrotal circumference and major and total defects, but did not influence motility or vigor. The highest proportion of adequate breeders was obtained with 24-month-old bulls and older.(AU)

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