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Este estudo teve como objetivo avaliar a ação do heterodímero PSP-I/PSP-II como marcador de congelabilidade e sua influência na proteção espermática durante a criopreservação do sêmen suíno. O sêmen de quatro varrões foi congelado na presença ou não do heterodímero. Após a descongelação, analisou-se a integridade acrossomal (sodas fluorescentes), integridade da membrana plasmática (sondas fluorescentes), a atividade mitocondrial (citoquimica) e a motilidade espermática (CASA). Para a integridade da membrana plasmática e acrossomal, o tratamento com 3,0 mg/mL de PSP-I/PSP-II apresentou uma maior porcentagem de células intactas (p

ABSTRACT The objective of the present study was to develop a methodology to obtain the enriched fraction of ram seminal vesicle protein 14 (RSVP14). The study was developed using Morada Nova rams, from which semen samples were collected weekly. Seminal plasma proteins were precipitated with cold ethanol, and then 6.15 mg/mL of total proteins were subjected to liquid gelatin affinity chromatography using a Gelatin-Sepharose matrix coupled to an automated chromatographic system. Proteins were eluted into four fractions (A, B, C, and D), in which A and B contained non-gelatin-binding proteins, and C and D fractions contained gelatin-binding proteins. Gels were analyzed by Quantity One software, in which five protein bands were detected in fraction D, with molecular weights between 12 and 30 kDa. The gelatin-binding proteins (fraction D) were loaded into a HiTrap™ Heparin HP affinity column. Two chromatographic fractions were separated (D1 and D2), in which D1 contained non-heparin-binding proteins, and D2 contained heparin-binding proteins. Proteins from the last two peaks were subjected to 12.5% SDS-PAGE and Western Blot. Two bands with molecular weight of 14 and 24 kDa, contained in fraction D1, were excised from gel and subjected to tandem mass spectrometry, identifying the proteins RSVP14 and RSVP24. Thus, the chromatographic methods of the present study are efficient to capture the enriched fraction of RSVP14.

Twenty-four Guzerat bulls were evaluated from 24 to 34 months of age, aiming to determinate the bulls serum testosterone concentration profile and their variation according to age, body weight and andrologic traits. The average of testosterone concentration was 1.36 ng/mL, with effect of time at harvest on circulating levels. The regression equation of testosterone according to body weight showed linear effect, suggesting that for each kilogram added to the body weight, an increase of 0.0082 ng/mL on serum testosterone concentrations occurs; and the regression of testosterone according to scrotal circumference (SC) also showed a linear effect. The results show that for each centimeter added to SC in Guzerat bulls, an increase of 0.2319 ng/mL on testosterone concentrations occurs. The regression of sperm concentration according to serum testosterone showed a linear effect, the results show that for each 0.1 ng/mL added to serum testosterone concentration, an increase of 9.29x106 spermatozoa/mL of semen occurs. The results indicate that circulating levels of testosterone may help on identification and selection of Guzerat bulls with major reproductive potential.

In order to determine the profile of leptin and insulin values in seminal plasma and their correlations with sperm patterns during the peripuberty, a total of 16 crossbred Gyr dairy bulls were monitored from 60 days before to 60 days after puberty, separated into two groups, early and regular, according to the onset of puberty. Hormone values were determined by radioimmunoassay after gel filtration in fast performance liquid chromatography and semen patterns, according to the Brazilian College of Animal Reproduction. Insulin concentrations in seminal plasma did not differ between groups, nor between the ages, with the pooling of the data showing average of 35.15±16.93, 36.60±26.21, 26.82±09.81, and 43.56±31.71 32.24±16.71 U/mL for the pubertal period of -60, -30, 0, +30 and +60 days, respectively. These values were not correlated with sperm parameters, but differed in the group of animals with the highest percentage of major defects (31.08±18.58 U/mL) compared with those with lower percentage of these sperm defects (40.01±25.37 U/mL). Leptin was not correlated with sperm parameters and did not differ between groups or stage of sexual development, with concentrations of 23.10±10.43, 24.35±9.42, 22.41±9.90, 23.76±9.69 and 24.99±11.42 ng/mL for the periods of puberty aforementioned, respectively, after being grouped. These results demonstrated the binding of insulin to the structural quality of the sperm cell, and this hormone is indicated in andrologycal evaluation of future breeding soundness.

Semen of twelve Tabapuã young bulls, which were according to patterns established by CBRA (1998) after cryopreservation, was submitted to fast and slow thermoresistence tests, hypoosmotic swelling test, induced acrosome reaction by heparin, sperm viability test by Trypanblue post-freezing and post-incubation with heparin, and pregnancy rates at first artificial insemination of Nellore heifers. Continuous variable averages of the mentioned tests were compared by Student–Newman–Keuls test and subjective variables were compared by Kruskal-Wallis nonparametric test (p0.05) to preview pregnancy rate, even if using the multiple regression model that included all variables. One can conclude that the model proposed in this study was not effective to predict pregnancy rate. Hypoosmotic Swelling Test can be suggested to evaluate functional and structural integrities of plasma membrane and the capacity of spermatozoa going through acrosome reaction.

This paper provides an evaluation of the population structure, phenotype and genetic trends of registered Gyr herd cattle in northeast Brazil. The study provides important baseline information for the management, conservation and potential population expansion of this economically and culturally important cattle breed. Pedigree data were analyzed for individuals born between 1964 and 2006. Body weight values were adjusted to 205 and 365 days of age for animals born between 1978 and 2006. Phenotypic change of zebu Gyr in northeast Brazil is solely due to environmental improvement. However, there is potential for artificial selection for weight gain in young cattle. Effective population size decreased during the 1990s and the average inbreeding coefficient increased during the studied period. An increase of the effective population size of Gyr in northeast Brazil is strongly recommended, along with an increase in the management of the mating process to prevent inbreeding and to maintain the genetic variability of the breed.Com o intuito de fornecer subsídios para programas de conservação, seleção e expansão da raça Gir no Nordeste do Brasil, objetivou-se avaliar o histórico do rebanho Gir registrado no nordeste brasileiro, com base na sua estrutura populacional e no progresso genético e fenotípico de características de desenvolvimento ponderal. Foram utilizadas informações de pedigree de animais nascidos no período de 1964 a 2006 e dados dos pesos ajustados aos 205 e 365 dias de idade de bovinos nascidos de 1978 a 2006. O progresso genético para a raça no Nordeste foi ocasionado exclusivamente pelo melhoramento ambiental. O tamanho efetivo da população reduziu a partir da década de 90, e o coeficiente de endogamia médio aumentou durante o período estudado. É imprescindível que o tamanho efetivo da raça Gir do nordeste seja ampliado e que haja maior controle de acasalamentos entre indivíduos aparentados, para prevenção da endogamia e conservação da variabilidade genética e viabilidade da raça.

Data from 583 Nelore bulls, aging from two and three years old, raised under pasture condition, were used to study andrologic traits (physical aspects: motility and vigor; and morphologic: major and total defects of the semen) and testicular measurements (scrotal circumference - SC and testicular volume - TVOL) to establish a profile of andrologic classification for fertility (BSE). The animals were divided in two groups: young bulls (N = 345), with ages from 18 to 30 months (2 years old), and adult (N = 238), with ages from 31 to 42 months (3 years old). Differences were observed (p < 0.05) for body weight, SC, physical and morphologic characteristics of the semen and TVOL in the two year olds with BSE above and below 60 points. In the three years old bulls differences were observed (p < 0.05) for SC and physical and morphologic characteristics of the semen in bulls with BSE above and below 60 points. The results suggested that body weight and SC affected the reproductive condition of young Nelore bulls. SC and seminal traits were the determining factors in the selection for a better reproductive condition, showing the importance of semen analysis when evaluating bulls raised under pasture conditions.KEY WORDS: Andrology, breeding soundness evaluation, scrotal circumference, semen, zebu. Avaliaram-se 583 touros Nelore, de dois e três anos de idade, criados extensivamente, para estudar as características andrológicas (aspectos físicos: motilidade e vigor espermáticos; e morfológicos: defeitos espermáticos maiores e totais) e de biometria testicular (circunferência escrotal – CE – e volume testicular – VOLT), permitindo classificá-los andrologicamente por pontos e estabelecer parâmetros andrológicos. Os animais foram divididos em dois grupos: touros jovens (N = 345), com idades de 18 a 30 meses (2 anos), e adultos (N = 238), com idades de 31 a 42 meses (3 anos). Observaram-se diferenças (p < 0,05) de peso, CE, características físicas e morfológicas do sêmen e VOLT nos animais de dois anos de idade com CAP acima e abaixo de 60 pontos. Nos animais de três anos de idade observaram-se diferenças (p < 0,05) de CE e características físicas e morfológicas do sêmen nos touros com CAP acima e abaixo de 60 pontos. Esses dados sugerem que peso e CE influenciam a condição reprodutiva de touros jovens da raça Nelore e que os fatores determinantes na seleção para uma melhor condição reprodutiva foram as CE, juntamente com as características seminais, indicando a importância da análise de sêmen na avaliação de touros criados a pasto. PALAVRAS-CHAVES: Andrologia, classificação andrológica por pontos, circunferência escrotal, sêmen, zebu.

O objetivo deste trabalho foi estimar correlações genéticas e fenotípicas de características reprodutivas e ponderais em 579 touros Nelore, em criação extensiva. As características reprodutivas estudadas foram: circunferência escrotal, consistência, volume e forma testiculares, comprimento dos testículos esquerdo e direito, largura dos testículos esquerdo e direito, motilidade e vigor espermáticos, defeitos espermáticos maiores, menores e totais e classificação andrológica por pontos. As características foram analisadas pelo método de máxima verossimilhança restrita, com algoritmos livres de derivadas, sob modelo animal, com inclusão da matriz de numeradores dos coeficientes de parentesco entre os animais e seus ascendentes. As correlações genéticas entre circunferência escrotal e as características peso corporal, volume testicular, motilidade espermática, vigor espermático, defeitos espermáticos menores, defeitos espermáticos totais e classificação andrológica por pontos foram, respectivamente, 0,72, 0,99, 0,72, 0,60, -0,67, -0,12 e 0,64. As maiores correlações fenotípicas encontradas entre peso e circunferência escrotal, características físicas e morfológicas do sêmen, quando comparadas às correlações entre idade e as mesmas características, são indicativas de que o peso tem maior influência na condição reprodutiva. As correlações genéticas entre classificação andrológica por pontos e as características: peso, circunferência escrotal, volume testicular, defeitos espermáticos maiores e defeitos espermáticos totais foram, respectivamente, 0,19, 0,64, 0,71, -0,47 e -0,58.The aim of this work was to estimate genetic and phenotypic correlations for sexual reproductive and productive traits using a Multiple Trait Derivative-Free Restricted Maximum Likelihood (MTDFREML) methodology in 579 Nelore bulls, raised under pasture. The reproductive traits analyzed were scrotal circumference, testicular consistency, testicular volume, testicular shape, length and width of right and left testicles, physical (motility and vigor) and morphological (major and minor, and total sperm defects) semen traits, and breeding soundness evaluation. Genetic correlations between scrotal circumference and body weight, testicular volume, motility, vigor, minor sperm defects, total sperm defects and breeding soundness evaluation were, respectively, 0.72, 0.99, 0.72, 0.60, -0.67, -0.12 e 0.64, showing favorable associations of scrotal circumference and the characteristics related. Phenotypic correlations of major magnitude found among ages and the above-related characteristics suggested to be the body weight the major factor affecting the reproductive performance of those animals. Genetic correlations among breeding soundness evaluation, body weight, scrotal circumference, testicular volume, major sperm defects and total sperm defects were, respectively, 0.19, 0.64, 0.71, -0.47 e -0.58.

Avaliaram-se 583 touros Nelore, de dois e três anos de idade, criados extensivamente, para estudar as características andrológicas (aspectos físicos: motilidade e vigor espermáticos; e morfológicos: defeitos espermáticos maiores e totais) e de biometria testicular (circunferência escrotal – CE – e volume testicular – VOLT), permitindo classificá-los andrologicamente por pontos e estabelecer parâmetros andrológicos. Os animais foram divididos em dois grupos: touros jovens (N = 345), com idades de 18 a 30 meses (2 anos), e adultos (N = 238), com idades de 31 a 42 meses (3 anos). Observaram-se diferenças (p < 0,05) de peso, CE, características físicas e morfológicas do sêmen e VOLT nos animais de dois anos de idade com CAP acima e abaixo de 60 pontos. Nos animais de três anos de idade observaram-se diferenças (p < 0,05) de CE e características físicas e morfológicas do sêmen nos touros com CAP acima e abaixo de 60 pontos. Esses dados sugerem que peso e CE influenciam a condição reprodutiva de touros jovens da raça Nelore e que os fatores determinantes na seleção para uma melhor condição reprodutiva foram as CE, juntamente com as características seminais, indicando a importância da análise de sêmen na avaliação de touros criados a pasto. PALAVRAS-CHAVES: Andrologia, classificação andrológica por pontos, circunferência escrotal, sêmen, zebu.