High percentage of midpiece defects in Brangus bull sperm with no reduction in sperm kinematics.

The study investigated midpiece defects in sperm from a 5-year-old Brangus bull with a high rate of semen batch rejection, due to morphologically abnormal sperm, with no reduction in sperm kinematics. A comprehensive evaluation was conducted over a 16-month period, involving 28 ejaculates. Notably, despite the high proportion of midpiece defects (average 37.73%, from 3% to 58%), the study revealed stable sperm production, with no discernible differences in the kinematic data before and after cryopreservation. Electron microscopy identified discontinuities in the mitochondrial sheath, characteristic of midpiece aplasia (MPA). The anomalies were attributed to be of genetic origin, as other predisposing factors were absent. Additionally, the electron microscopy unveiled plasma membrane defects, vacuoles and chromatin decondensation, consistent with previous findings linking acrosome abnormalities with midpiece defects. The findings underscored the necessity of conducting thorough laboratory evaluations before releasing cryopreserved semen for commercialization. Despite substantial morphological alterations, the initial semen evaluation data indicated acceptable levels of sperm kinematics, emphasizing the resilience of sperm production to severe morphological changes. This case report serves as a contribution to the understanding of midpiece defects in bull sperm, emphasizing the need for meticulous evaluation and quality control in semen processing and commercialization.

Espermiogênese alterada em um touro doador de sêmen: relato de caso / Altered spermiogenesis in a semen donor bull: case report

A espermiogênese é o processo final da espermatogênese no qual a espermátide se transforma em espermatozoide. Durante esse processo podem ocorrer alterações espermáticas, especialmente no acrossoma, na morfologia da cabeça, na condensação da cromatina e na formação dos vacúolos nucleares. A diferenciação entre os quadros clínicos é feita com repetições dos exames andrológicos. A avaliação morfológica indica a situação da espermiogênese nas 4 semanas anteriores a coleta do sêmen. Com os resultados do exame andrológico é possível identificar a qualidade seminal naquele período. O presente artigo é o relato de caso de um touro jovem doador de sêmen com 26 meses de idade, no início do regime de coletas de sêmen em um Centro de Coleta e Processamento de Sêmen no Sul do Brasil. A produção espermática deste animal foi avaliada durante 12 meses de coleta, apresentando sempre morfologia espermática muito alterada e motilidade média de 54% no exame imediato. Em 13 coletas seminais, o ejaculado deste animal apresentou em média 86% de defeitos maiores, 10% de defeitos menores e 96% de defeitos totais. Os defeitos maiores, que são os que possuem maior efeito na fertilidade, estão diretamente ligados a espermiogênese e os defeitos menores, que possuem menor efeito na fertilidade, são ocasionados principalmente durante o trânsito pelo epidídimo. O quadro clínico desse animal demonstrou a importância do exame morfológico para avaliar a espermatogênese e principalmente o processo de diferenciação final da espermátide em espermatozoide. Casos como este devem ser descritos como espermiogênese alterada e o reprodutor deve ser afastado da reprodução, após descartar alterações morfológicas devido a degeneração testicular grave.(AU)

Spermiogenesis is the final process of spermatogenesis in which the spermatid transforms into sperm. During this process, sperm alterations may occur, especially in the acrosome, head morphology, chromatin condensation and formation of nuclear vacuoles. Differentiation between clinical conditions is made with repetitions of andrological exams. The morphological evaluation indicates the status of spermiogenesis in the 4 weeks prior to semen collection. With the results of the breeding soundness examination, it is possible to identify the seminal quality in that period. The present article is a case report of a young 26-month-old semen donor bull, that started semen collection routines at a Semen Collection and Processing Center in southern Brazil. The sperm production of this animal was evaluated during 12 months of collection, always showing very altered sperm morphology and average motility of 54% in the immediate examination. In 13 seminal collections, the ejaculate of this animal presented an average of 86% of major defects, 10% of minor defects and 96% of total defects. Major defects, which have the greatest impact on fertility, are directly linked to spermiogenesis and minor defects, which have less effect on fertility, are mainly caused during transit through the epididymis. The clinical conditions of this animal demonstrated the importance of the morphological examination to evaluate spermatogenesis and especially the process of final differentiation of the spermatid into spermatozoa. Cases like this should be described as altered spermiogenesis and the bull should be withdrawn from breeding, after ruling out morphological changes due to severe testicular degeneration.(AU)

Morfologia espermática em touros: quais os principais defeitos e o porquê ocorrem / Sperm morphology in bulls: which are the main defects and why they occur

A morfologia espermática é uma característica seminal que está associada à fertilidade e é, portanto, um componente importante na rotina do controle de qualidade em Centros de Coleta e Processamento de Sêmen (CCPS). É utilizada para caracterizar e quantificar os vários tipos de anormalidades nas células espermáticas do touro, usando preparação em montagem úmida para microscopia de Contraste de Interferência Diferencial (DIC), Contraste de Fase (CF) e Lâmina Corada (LC). O perfil da morfologia espermática permite a tomada de decisão sobre o aproveitamento ou descarte de um ejaculado para criopreservação e predizer a fertilidade de uma amostra de sêmen. Alterações no espermograma, com evidências do histórico e exame físico do touro, levam a interpretação da função testicular anormal, e consequentemente, ao diagnóstico, tratamento e prognóstico, se for o caso. As causas mais comuns de uma espermatogênese anormal nos touros incluem: termorregulação testicular anormal, desequilíbrios hormonais, estresse de manejo, ambiental e nutricional, efeitos de toxinas ou expressão de genes deletérios, além de defeitos de origem genética. Conhecendo-se a estrutura do espermatozoide, torna-se mais fácil a identificação das anormalidades espermáticas bem como a descrição das mesmas e uma melhor compreensão de sua origem.(AU)

Sperm morphology is a seminal trait that is associated with fertility and is therefore an important component of routine quality control in Semen Collection and Processing Centers (SCPC). It is used to characterize and quantify the various types of abnormalities in bull sperm cells, using wet mount preparation for Differential Interference Contrast (DIC), Phase Contrast (PC) and Slides Smear (SS) microscopy. The sperm morphology profile allows decision making on the use or disposal of an ejaculate for cryopreservation and predicts the fertility of a semen sample. Changes in sperm morphology may indicate that fertility may be impacted and therefore it is important to routinely monitor ejaculates. An abnormal spermogram with evidence from a history and physical examination of the bull can lead to the interpretation of abnormal testicular function, and consequently, to the diagnosis, treatment and prognosis, if any. The most common causes of abnormal spermatogenesis in bulls include: abnormal testicular thermoregulation, hormonal imbalances, management, environmental and nutritional stress, effects of toxins or expression of deleterious genes, in addition to defects of genetic origin. Knowledge in the structure of the sperm makes easier the identification of sperm abnormalities, as well as their description and provides a better understanding of their origin.(AU)

Tourinhos genômicos: relação da qualidade e congelabilidade do sêmen / Genomic young bulls: relationship between semen quality and freezeability

A grande demanda por sêmen congelado para inseminação artificial no Brasil está ocasionando que criadores, programas genéticos, e centros de coleta e processamento de sêmen produzam touros cada vez mais jovens para doação de sêmen. A avaliação genômica é uma nova ferramenta para a seleção de touros jovens para os centros de coleta, porém, junto vieram os problemas na seleção de bons doadores de sêmen que muitas vezes não atingem a puberdade na idade desejada, principalmente na raça Nelore que é a mais importante para o mercado de inseminação no país. A maioria dos problemas com a produção de sêmen do touro jovem genômico podem ser resolvidos com o tempo, mas ainda ocasiona vários problemas não resolvidos. Os touros jovens genômicos da raça Nelore atingem a puberdade entre 13 a 16 meses e os touros jovens das raças Holandesa e Angus entre 10 a 12 meses de idade sendo que a maturidade sexual no geral é alcançada entre 18 a 24 meses quando passam a produzir sêmen rotineiramente e produzem grandes quantidades de unidades de sêmen criopreservado para uso na inseminação artificial. Este cenário ocasionará um problema para o mercado da inseminação artificial, com a demanda de mais touros com maturidade sexual.(AU)

The great demand for frozen semen in the artificial insemination in Brazil is causing breeders, genetic programs, and semen collection and processing centers to produce ever younger bulls for semen donation. The genomic evaluation is a new tool for the selection of young bulls for the collection centers, however, along came the problems in the selection of good semen donors that often do not reach puberty at the desired age, especially in the Nellore breed, the most important for the insemination market in the country. Most problems with genomic young bull semen production can be resolved over time, but there are still several unresolved problems. Young genomic Nellore bulls reach puberty between 13 to 16 months and young Holstein and Angus bulls between 10 to 12 months of age and sexual maturity is generally reached between 18 to 24 months when they start to produce semen routinely, so producing a large quantities of cryopreserved semen units for use in artificial insemination. This will cause a problem for the artificial insemination business where more sexually mature bulls will be needed.(AU)

Comparação de diluidores comerciais na motilidade, funcionalidade e integridade da membrana plasmática do espermatozoide bovino / Comparison of commercial diluents on motility, functionality and integrity of plasma membrane of bovine spermatozoa

O objetivo do estudo foi comparar o efeito de três diluidores comerciais (Tryladil®, Botu-Bov® e OptiXcell®) na qualidade do espermatozoide bovino após o processo de criogenia. Para tal, foram utilizados oito touros da raça Nelore (2 ejaculados/touro). As amostras de sêmen fresco, diluído e pós-descongelamento foram avaliadas, comparando os parâmetros de motilidade total, vigor, funcionalidade da membrana (HOST) e integridade da membrana (eosina). Os dados foram expressos em média e desvio padrão. As variáveis foram submetidas às análises de ANOVA e Tukey ou teste de Friedman e Dunn's, dependendo da normalidade (p< 0,05). Os achados mostram que no momento da diluição não houve diferença (p˃0,005) entre os diluidores comerciais nos parâmetros avaliados (exceto integridade da membrana plasmática). No entanto, no momento do pós-descongelamento os espermatozoides criopreservados utilizando-se o diluidor Tryladil® apresentaram maiores valores (p˂0,005) referentes a integridade e funcionalidade da membrana plasmática comparado aos diluídos em Botu-Bov® e OptIXcell®. Os parâmetros relacionados a cinética espermática (motilidade e vigor) não se diferiram (p˃0,005) entre os diluidores comerciais utilizados. Em conclusão, no momento pós-descongelamento o diluidor Tryladil® apresentou os melhores resultados nos parâmetros de integridade e funcionalidade da membrana plasmática. Sendo assim, recomenda-se o diluidor Tryladil® para criopreservação de sêmen de bovinos da raça Nelore.

The main of the study was to compare the quality of frozen bull semen processed with three different commercially extenders (Tryladil®, Botu-Bov® and OptiXcell®). For this, eight Nelore bulls (two ejaculate per bull). Sperm samples were analyzed fresh, diluted and frozen-thawed. The parameters analyzed were total motility, sperm vigor, functional integrity of sperm plasma membrane (HOST) and plasma membrane integrity (eosin). Date were expressed as mean and standard deviation. The variables were subjected to ANOVA (Tukey test) or Friedman (Dunn's test) test according to normality (p< 0,05). The results indicate that there was no difference (p˃0,005) among all treatments in the parameters evaluated (except plasma membrane integrity) at dilution moment. However, Tryladil extender promoted an increase (p˂0,005) in functional and integrity of sperm plasma membrane compared with others extenders at the post-thawing analyze. After thawing, there was no difference (p˃0,005) among all treatments in the kinetic parameters. In conclusion, the Tryladil® extender promoted an increase in functional and integrity of frozen-thawed sperm plasma membrane. Therefore, the Tryladil® extender is recommended to be use as an extender for Nelore bull sperm cryopreservation.

Comparação de diluidores comerciais na motilidade, funcionalidade e integridade da membrana plasmática do espermatozoide bovino / Comparison of commercial diluents on motility, functionality and integrity of plasma membrane of bovine spermatozoa

O objetivo do estudo foi comparar o efeito de três diluidores comerciais (Tryladil®, Botu-Bov® e OptiXcell®) na qualidade doespermatozoide bovino após o processo de criogenia. Para tal, foram utilizados oito touros da raça Nelore (2 ejaculados/touro).As amostras de sêmen fresco, diluído e pós-descongelamento foram avaliadas, comparando os parâmetros de motilidade total,vigor, funcionalidade da membrana (HOST) e integridade da membrana (eosina). Os dados foram expressos em média e desviopadrão. As variáveis foram submetidas às análises de ANOVA e Tukey ou teste de Friedman e Dunns, dependendo da normalidade(p 0,05). Os achados mostram que no momento da diluição não houve diferença (p0,005) entre os diluidores comerciais nosparâmetros avaliados (exceto integridade da membrana plasmática). No entanto, no momento do pós-descongelamento osespermatozoides criopreservados utilizando-se o diluidor Tryladil® apresentaram maiores valores (p0,005) referentes a integridade efuncionalidade da membrana plasmática comparado aos diluídos em Botu-Bov® e OptIXcell®. Os parâmetros relacionados a cinéticaespermática (motilidade e vigor) não se diferiram (p0,005) entre os diluidores comerciais utilizados. Em conclusão, no momentopós-descongelamento o diluidor Tryladil® apresentou os melhores resultados nos parâmetros de integridade e funcionalidade damembrana plasmática. Sendo assim, recome

The main of the study was to compare the quality of frozen bull semen processed with three different commercially extenders (Tryladil®, Botu-Bov® and OptiXcell®). For this, eight Nelore bulls (two ejaculate per bull). Sperm samples were analyzed fresh, diluted and frozen-thawed. The parameters analyzed were total motility, sperm vigor, functional integrity of sperm plasma membrane (HOST) and plasma membrane integrity (eosin). Date were expressed as mean and standard deviation. The variables were subjected to ANOVA (Tukey test) or Friedman (Dunns test) test according to normality (p< 0,05). The results indicate that there was no difference (p˃0,005) among all treatments in the parameters evaluated (except plasma membrane integrity) at dilution moment. However, Tryladil extender promoted an increase (p˂0,005) in functional and integrity of sperm plasma membrane compared with others extenders at the post-thawing analyze. After thawing, there was no difference (p˃0,005) among all treatments in the kinetic parameters. In conclusion, the Tryladil® extender promoted an increase in functional and integrity of frozen-thawed sperm plasma membrane. Therefore, the Tryladil® extender is recommended to be use as an extender for Nelore bull sperm cryopreservation.(AU)

História da inseminação artificial no Brasil / History of artificial insemination in Brazil

A inseminação artificial foi a primeira biotecnologia reprodutiva empregada no melhoramento genético animal no Brasil. Consideráveis avanços ocorreram desde a década de 1930 até hoje, graças aos veterinários, técnicos de campo e criadores pioneiros, que não mediram esforços para que a técnica se tornasse o maior evento da produção animal, democratizando o uso de reprodutores geneticamente superiores. Esta revisão apresenta o contexto histórico da inseminação artificial no Brasil, que permitiu ao país ser considerado um exemplo do agronegócio pecuário para o mundo.

Artificial insemination was the first reproductive biotechnology used in animal genetic improvement in Brazil. It has occurred since the 1930s until today, advances considerable due to the veterinarians, field technicians and pioneering breeders, who they did not measure efforts for the technique to become the biggest event in the animal production, democratizing the use of genetically superior sires. This review presents the historical context of artificial insemination in Brazil, which allowed the country to be considered an example of livestock agribusiness in the world.

História da inseminação artificial no Brasil / History of artificial insemination in Brazil

A inseminação artificial foi a primeira biotecnologia reprodutiva empregada no melhoramento genético animal no Brasil. Consideráveis avanços ocorreram desde a década de 1930 até hoje, graças aos veterinários, técnicos de campo e criadores pioneiros, que não mediram esforços para que a técnica se tornasse o maior evento da produção animal, democratizando o uso de reprodutores geneticamente superiores. Esta revisão apresenta o contexto histórico da inseminação artificial no Brasil, que permitiu ao país ser considerado um exemplo do agronegócio pecuário para o mundo.(AU)

Artificial insemination was the first reproductive biotechnology used in animal genetic improvement in Brazil. It has occurred since the 1930s until today, advances considerable due to the veterinarians, field technicians and pioneering breeders, who they did not measure efforts for the technique to become the biggest event in the animal production, democratizing the use of genetically superior sires. This review presents the historical context of artificial insemination in Brazil, which allowed the country to be considered an example of livestock agribusiness in the world.(AU)

Efeito da aplicação de flunixin meglumine sobre a taxa de gestação de ovelhas inseminadas via transcervical / Effect of Flunixin Meglumine Injection on Pregnancy Rate of Ewes Inseminated by Transcervical Technique

Background: In livestock animals, which artificial insemination (AI) is widely spread, a healthy uterine environment is an important factor that should be taken into account for an adequate fertilization and establishment and development of pregnancy. The main limitation to spread the frozen semen insemination in sheep is the high costs of the laparoscopy AI and the difficulty of traversing the cervix. To overcome problems associated with transcervical artificial insemination, new techniques and instruments have been proposed. The manipulation of cervix during transcervical artificial insemination in sheep can lead to a local inflammatory reaction that releases inflammatory mediators, such as prostaglandins and cytokines, that either can negatively affect the uterine environment and consequently, the conception. In this regard, the injection of a non-steroidal anti-inflammatory (NSAI) at the moment of AI could reduce the secretion of inflammatory mediators, promoting a healthier uterine environment favorable to conception. The flunixin meglumine is a NSAI which reduces the synthesis of PGF2α by the inibition of the cyclooxigenase. The objective of this study was to evaluate the effect of flunixin meglumine (non-steroid antiinflammatory) injection on pregnancy rate of ewes inseminated by the transcervical technique. Materials, Methods & Results: In this experiment 69 pluriparous ewes were used, 29 in control group (CG) and 40 in flunixin meglumine group (FMG). The estrus detection was performed twice daily for 5 days. The ewes detected with paint in the low back were considered in estrus. The AI procedure was performed 8 h after the estrus detection. At the AI time, the ewes were separated according to body condition score in two experimental groups. The ewes of the FM Group were injected with 1.1 mg/ Kg of flunixin meglumine, im, 1 h before the AI procedure. In order to locate the ostium, a vaginal speculum and a source of external light were used;(...)

Efeito da aplicação de flunixin meglumine sobre a taxa de gestação de ovelhas inseminadas via transcervical / Effect of Flunixin Meglumine Injection on Pregnancy Rate of Ewes Inseminated by Transcervical Technique

Background: In livestock animals, which artificial insemination (AI) is widely spread, a healthy uterine environment is an important factor that should be taken into account for an adequate fertilization and establishment and development of pregnancy. The main limitation to spread the frozen semen insemination in sheep is the high costs of the laparoscopy AI and the difficulty of traversing the cervix. To overcome problems associated with transcervical artificial insemination, new techniques and instruments have been proposed. The manipulation of cervix during transcervical artificial insemination in sheep can lead to a local inflammatory reaction that releases inflammatory mediators, such as prostaglandins and cytokines, that either can negatively affect the uterine environment and consequently, the conception. In this regard, the injection of a non-steroidal anti-inflammatory (NSAI) at the moment of AI could reduce the secretion of inflammatory mediators, promoting a healthier uterine environment favorable to conception. The flunixin meglumine is a NSAI which reduces the synthesis of PGF2α by the inibition of the cyclooxigenase. The objective of this study was to evaluate the effect of flunixin meglumine (non-steroid antiinflammatory) injection on pregnancy rate of ewes inseminated by the transcervical technique. Materials, Methods & Results: In this experiment 69 pluriparous ewes were used, 29 in control group (CG) and 40 in flunixin meglumine group (FMG). The estrus detection was performed twice daily for 5 days. The ewes detected with paint in the low back were considered in estrus. The AI procedure was performed 8 h after the estrus detection. At the AI time, the ewes were separated according to body condition score in two experimental groups. The ewes of the FM Group were injected with 1.1 mg/ Kg of flunixin meglumine, im, 1 h before the AI procedure. In order to locate the ostium, a vaginal speculum and a source of external light were used;(...)(AU)