Two experiments were conducted to evaluate sexual development in early- and late-maturing Nelore (Bos indicus) and Canchim (3/8 Bos indicus x 5/8 Bos taurus crossbred) bulls and to determine predictors of sexual precocity, and pubertal and maturity status. In Experiment 1, 12 Nelore bulls where examined from 300 to 900 days of age. Puberty was characterized by an ejaculate containing > or =50 million sperm with > or =10% motile sperm, and maturity by an ejaculate containing > or =70% morphologically normal sperm. In Experiment 2, 28 Canchim bulls where examined from 295 to 488 days of age and puberty was characterized by an ejaculate containing > or =30% motile sperm. In both experiments, bulls were classified as early- or late-maturing based on age at puberty. Early-maturing bulls were younger (P < 0.05) than late-maturing bulls at puberty (527 days versus 673 days in Experiment 1 and 360 days versus 461 days in Experiment 2) and at maturity (660 days versus 768 days in Experiment 1). In general, early-maturing bulls were heavier and had greater scrotal circumference (SC), testes, and testicular vascular cone diameter than late-maturing bulls during the experimental period. Scrotal circumference adjusted for 365 days of age was a good predictor of sexual precocity; minimum yearling SC of 19 and 24 cm for Nelore and Canchim bulls, respectively, had the best predictive values. Early-maturing bulls were lighter and had smaller SC at puberty than late-maturing bulls; therefore, sexual precocity was not related to the attainment of a threshold body weight or testicular size earlier, but to lower thresholds in early-maturing bulls. When predictors of pubertal status were evaluated, SC had the best sensitivity/specificity relationship in Nelore bulls, and high sensitivity and specificity in Canchim bulls. When predictors of sexual maturity were evaluated in Nelore bulls, age, weight, and SC had similar sensitivity, specificity, and predictive values. At puberty, approximately 60% of the sperm present in the ejaculate were morphologically defective. Changes in semen quality after puberty in Nelore bulls were characterized by increased motility and proportion of morphologically normal sperm, with a decrease in the proportion of major sperm defects. In conclusion, early-maturing bulls were more developed in the pre-pubertal period and attained puberty at earlier stages of body and testicular development than late-maturing bulls. Yearling SC could be used to select bulls for sexual precocity and SC was the best predictor of pubertal status. Age, weight, and SC were equally good predictors of sexual maturity in B. indicus bulls.

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RESUMO -O objetivo deste estudo foi analisar as características de volume e forma testicular em zebuínos jovens da raça Nelore para caracterizar a sua importância na avaliação e seleção de reprodutores. Foram examinados a circunferência escrotal (CE), o comprimento (COMP), a largura (LARG) e o volume testicular (VOL) em 442 machos aos 12 e 18 meses de idade, divididos em dois grupos contemporâneos (G1 e G2), em função da data do nascimento. O VOL foi calculado pela fórmula: VOL = 2[(r 2 ) x Π x h] em que r = LARG/2, h = COMP, e Π = 3,14. A forma dos testículos foi avaliada pela razão LARG/COMP, resultando em cinco formas: longa (razão ≤ 0,5), longa moderada (razão de 0,51 a 0,625), longa/oval (razão de 0,626 a 0,750), oval/esférica (razão de 0,751 a 0,875) e esférica (razão > 0,875). Em 87% dos animais, os testículos apresentaram forma longa e, em 74%, houve mudança da forma testicular com a idade. Os parâmetros estudados variaram em função da forma testicular, e o crescimento dos testículos ocorreu em largura. Os resultados sugerem que, ao selecionar reprodutores, principalmente jovens, deve-se considerar o volume testicular, além de possíveis mudanças da forma testicular.Palavras-chave: forma testicular, Nelore, touro, volume testicular Testicular Biometrics Characteristics to Evaluate the Nellore Zebu Breed BullsABSTRACT -The objective of this study was to analyze the testicular volume and shape in young males of Nellore Zebu breed and their importance for the evaluation and selection of sires. Four hundred and forty two males, from 12 to 18 month of age, were examined for scrotal circumference (CE), length (COMP), width (LARG) and testicular volume (VOL). The animals were divided in two groups (G1 and G2) according to their date of birth. The VOL was calculated by the formula: VOL = 2[(r 2 ) x Π x h], where r, h and Π are LARG/2, length and 3.14, respectively. The mean values of CE, COMP, LARG and VOL at 12 month of age were 184.89±15.79 mm, 65.96±6.48 mm, 2.58±4.63 mm and 113.80±42.03 cm 3 , and at 18 months of age were 236.81±mm, 79.31±11.16 mm, 42.92±5.83 mm and 239.26±90.56 cm 3 , respectively. The parameters at 12 and 18 months of age were influenced by contemporary groups, being highly correlated. The testicular shape was considered as a length to width ratio, being recorded five forms: long (ratio ≤ .5), long moderate (.51 to .626 ratio), long/ ovoid (.626 to .750 ratio), ovoid/spheroid (.751 to .875 ratio) and spheroid (> .875 ratio). 87% of the animals presented the long shape and, in 74%, the testicular shape changed with the age. All the parameters were influenced by testicular shape, and the testis grew in width. The results suggest that the selection of young bulls should consider the testicular volume besides the possible change in the testicular shape. IntroduçãoConstam do processo de seleção de reprodutores várias características morfo-fisiológicas do aparelho reprodutor, como a circunferência ou o perímetro escrotal e, ainda, mais recentemente, a avaliação quanti-qualitativa do sêmen.Na pre...

This study reports the incidence of abscesses in relation to Corynebacterium pseudotuberculosis infection in goats in north-east Brazil. Among 656 goats examined periodically over almost two years 41.6% were found with superficially palpable abscesses. Most of the infected areas were in the anterior half of the body in front of the pre-scapular region; the inguinal region formed the other prominent area. Among 486 dead or slaughtered goats, 56 (11.5%) revealed abscesses in the internal organs. Lungs and epididymis were affected most, liver, spleen, udder and lateropharyngeal nodes were next in order and kidneys and mediastinal nodes were least affected. Thus the overall incidence of external and internal abscesses was 28.8%; of all the abscesses 27.7% were due to C. pseudotuberculosis and the rest due to infections of Corynebacterium pyogenes and several species of streptococci or staphylococci. The growth of C. pseudotuberculosis-infected and non-infected goats was of the same order and it seems that caseous lymphadenitis is not the cause of much financial loss in north-east Brazil but in view of its high incidence remedial measures should be considered necessary in regions where the goat meat industry is likely to become more intensive and important.

RESUMO -Em 960 touros da raça Nelore, PO, de 11,4 a 135 meses de idade, pertencentes a fazendas localizadas nos Estados de São Paulo, Goiás e Pará, estudou-se a possível associação entre o tamanho da circunferência escrotal (CE) e os parâmetros da qualidade do sêmen, motilidade progressiva (MOT) e patologias espermáticas: defeitos maiores (DEFMAI), menores (DEFMEN) e totais (DEFTOT). Os touros foram divididos por faixas etárias em: menores que 18, de 18 a 24, de 24 a 30, de 30 a 36 e maiores que 36 meses de idade. Este estudo foi realizado com a finalidade de obter tamanhos de CE que possam indicar o estatus funcional dos testículos, ou seja, a qualidade do sêmen, a serem utilizados para predizer o potencial reprodutivo dos animais destinados à seleção de reprodutores. Da correlação da CE com a MOT, por faixa etária, resultou uma associação (R=0,60; P<0,0001) destes parâmetros nos touros até 18 meses de idade, em que CEs acima de 26 cm indicaram sêmen de alta MOT (60 a 80%). As correlações entre CE e patologias espermáticas foram baixas e a maioria, negativa. Foi concluído, neste estudo, que nos touros jovens o tamanho da CE indica a qualidade do sêmen, portanto pode ser utilizado como um dos critérios na seleção de animais de alto potencial reprodutivo.Palavras-chave: circunferência escrotal, motilidade, Nelore, patologias espermáticas Relationship of Scrotal Circumference and the Semen Quality Parameters in NellorePurebred Bulls ABSTRACT -In 960 Nellore purebred bulls, of 11.4 to 135 months of age, belonging to farms located in the São Paulo, Goiás and Para states, was studied the possible association among the size of the scrotal circumference (CE) and sperm quality parameters, progressive motility (MOT) and sperm pathologies: the major (DEFMAI), minor (DEFMIN) and total (DEFTOT) defects. The bulls were divided by age in groups: minor than 18, from 18 to 24, from 24 to 30, from 30 to 36 and major than 36 months of age. This study was accomplished with the purpose of obtaining sizes of CE that may indicate the functional status of the testicles through the quality of the semen that can be used to predict the reproductive potential of the animals destined to the selection of bulls. Of the correlation of CE with MOT, by age group, resulted an association (R = 0,60; P<0.0001) of these parameters in the bulls up to 18 months of age, which CE above 26 cm indicated semen of high MOT (60 to 80%). The correlation between CE and sperm pathologies was very low and negatives. It was concluded that in the young bulls the size of CE indicates the quality of the semen, therefore it can be used as a criteria for the selection of animals of high reproductive potential.Key Words: motility, Nellore, scrotal circumference, sperm pathologies 1 Pesquisador, Embrapa Recursos Genéticos e Biotecnologia, PqEB, Final Av.W 5 Norte, Brasília/DF. E. mail: emidio@cenargen.embrapa.br; unanianm@aol.com 2 Pesquisador, Embrapa Pecuária Sudeste, São Carlos/SP. . Zootec., v.31, n.3, p.1157-1165, 2002 Introdução A eficiência ou capacidade reprodu...