The aim of this study was to assess the seasonal effects of the environment on semen quality in bulls, using infrared thermography. Sperm motility (M), mass motion (MM), and vigor (VIG) were evaluated in sperm samples from 17 Bradford bulls aged approximately 24 months at the beginning of the study. Infrared thermography images and data were collected using an infrared FLIR T 300 camera and Quick Report 1.2 SP2 software to determine the temperature of the proximal and distal poles of the testis and to assess the testicular temperature gradient. The seasonal effects on physiological, seminal, and climatic variables were analyzed by the GLM ANOVA and CORR procedures using SAS®. The microclimatic factors were recorded in hourly intervals, and the daily mean temperature and mean relative humidity were calculated to determine the daily temperature-humidity index (THI) every day for 1 year. The temperature gradient (TG) variations of the testes were significantly higher in the autumn (4.5 °C), winter (4.0 °C), and spring (2.9 °C) compared to summer (0.9 °C) (P < 0.05). Ocular globe temperatures were lower in the winter (27.6 °C) and autumn (26.8 °C) compared to summer (33.9 °C) and spring (31.1 °C) (P < 0.05). The average MM (2.58), M (52.64), and VIG (2.70) of the semen decreased in the summer compared to other seasons (P < 0.01). The TG was negatively correlated with THI (-0.44; P < 0.05). For the seminal variables, MaD (-0.45; P < 0.05) and TD (-0.50; P < 0.01) presented a negative correlation with TG. The TG had a positive correlation between M and VIG, which had values of 0.36 and 0.35, respectively (P < 0.05). We have concluded that infrared thermography can be used to assess the testicular temperature gradient and its consequences on physical and quantitative aspects of sperm.

This study evaluated the thermoregulation and spermatogenic changes by scrotal temperature gradient using infrared thermography in testicular compromised bulls. Bulls were insulated (n = 6) for 72 hr and control animals (n = 3) remained without insulation during all the experimental period. Seminal evaluation was performed prior, at insult removal and once per week for 13 consecutive weeks. Mean temperature gradient in insulated animals was lower at the time of insulation removal compared to the week prior and after the insult (p < .05). Two weeks after insult, sperm motility was lower in insulated compared to control animals (p < .01) and spermatozoa total defects were higher in insulated compared to control animals (p < .05). Two and seven weeks after insult, the major defects were higher in insulated compared to control animals (p < .05). Scrotal temperature gradient showed a positive correlation with sperm mass motion (p < .01) and a negative correlation with ocular globe temperature (p < .01) in insulated animals. The infrared thermography can be used to evaluate ocular globe temperature in bulls; however, it is only effective to detect changes in scrotal temperature gradient at the insult removal.

The aim of this study was to evaluate the bioclimatic thermal stress assessed by Equivalent Temperature Index (ETI) and Temperature Humidity Index (THI) on Braford and Nellore bulls sperm quality during the reproductive seasons at the tropical region in the Brazilian Pantanal. We used 20 bulls aged approximately 24 months at the beginning of the study. Five ejaculates per animal were collected using an electroejaculator. Temperature, air humidity, and wind speed data were collected every hour from the automatic weather station at the National Institute of Meteorology. Infrared thermography images data were collected to assess the testicular temperature gradient in each animal. Data were analyzed with ANOVA using MIXED procedure of SAS and means were compared using Tukey's HSD test. The THI and ETI at 12 days (epididymal transit) were higher in January (89.7 and 28.5, respectively) and February (90.0 and 29.0, respectively) compared to other months (P < 0.01). Total seminal defects differ only in Bradford bulls between the months of November and February. Nellore bulls had lower major defects (MaD) and total defects (TD) compared to Braford. Nellore bulls showed correlation between minor defects (MiD) and THI for 30 days (0.90) and 18 days (0.88; P < 0.05). Braford bulls showed correlation for MaD (0.89) in ETI for 12 days (P < 0.05). Infrared thermography showed no difference between animals. Reproductive response to environmental changes is a consequence of Nellore and Braford adaptation to climate stress conditions. Both THI and ETI environmental indexes can be used to evaluate the morphological changes in the seminal parameters in Nellore or Braford bulls; however, more experiments should be performed focusing on larger sample numbers and also in reproductive assessment during the consecutive years to assess fertility potential.

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ResumoEste estudo teve como objetivo estudar o efeito de dietas com diferentes proporções de concentrado na terminação de cordeiros Texel sobre as características das carcaças e carne ovina. Foram utilizados 12 cordeiros da raça Texel com peso inicial de 20,1±2,34kg. Foram avaliadas rações com três proporções de concentrado na ração total (60, 80 e 100%) e quatro repetições por tratamento. O concentrado foi composto por 15%suplemento nutricional + 85% grão de milho inteiro e o volumoso foi feno de Aveia (Avena strigosa). O rendimento verdadeiro da carcaça foi superior para os animais consumindo 100% de concentrado na dieta, em média 58,3%. Os valores da área de olho de lombo, acabamento e os pesos de costilhar e pernil foram superiores (P<0,05) para os animais recebendo 80 e 100% de concentrado na dieta em relação aos animais consumindo 60%. Cordeiros recebendo 100% da dieta com alto grão apresentaram maiores rendimentos, área de olho de lombo e acabamento de carcaça, características essas relevantes em relação à questão produtiva fornecendo animais com maior porção de carne comestível e com qualidade satisfatória ao mercado consumidor. Os teores de concentrado na dieta não alteraram os parâmetros qualitativos e sensoriais da carne de cordeiros terminados em confinamento, características essas que poderão garantir maior aceitação do produto final, recomendando-se assim a utilização de dietas contendo alto teor de concentrado para cordeiros da raça Texel. Palavras-chave: Coloração, força de cisalhamento, ovinos, pH, sensorial AbstractThis study aimed to investigate the effect of diets with different proportions of concentrate in finishing lambs Texel on carcass characteristics and meat sheep. Twelve Texel lambs with an initial weight of 20.1 ± 2.34 kg were used. The treatments consisted of three levels of concentrate in the total ration (60,

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This study aimed at estimating the heritability of age at first calving and of performance traits included in the selection index and the genetic correlations between age at first calving and these performance traits. Data were extracted from the Conexão Delta G database and only data from herds in which heifers were bred younger than 24 months of age were used, resulting in a file with 331,310 evaluated animals. The following traits were included in the analyses: age at first calving, birth to weaning gain, post-weaning weight gain, visual scores of conformation, precocity, and muscling evaluated at weaning and in yearling heifers. Covariance components were obtained by bi-character analyses between traits. An alternative age at first calving was also taken into account, in which all heifers were used, including those that were mated and did not calve. Covariance components and estimates of the effects included in the model were obtained using the software program DMU. Heritability estimates were 0.11 and 0.13 for age at first calving and alternative age at first calving, 0.38 for birth to weaning gain, and 0.13 for post-weaning weight gain. Visual score estimates ranged between 0.16 and 0.18 at weaning and 0.19 and 0.29 in yearlings. Genetic correlation estimates of the traits were low, but in the desirable direction. Selection for birth to weaning gain and visual scores does not have a negative effect on age at first calving or alternative age at first calving.

RESUMO: A vesiculite é um processo inflamatório das glândulas vesiculares, podendo ser unilateral ou bilateral, que acomete reprodutores. O objetivo do presente trabalho foi avaliar a utilização da ultrassonografia como meio de diagnóstico precoce das alterações das vesículas seminais em touros. O presente trabalho foi realizado no município de Videira, Santa Catarina. Analisou-se um total 42 reprodutores, com média de idade de 15 meses, das raças Aberdeen Angus e Polled Hereford em semi-confinamento. Foi realizado exame clinico do estado geral dos animais e exame andrológico dos reprodutores. As amostras de sêmen para a realização do exame das características físicas do ejaculado foram obtidas por eletroejaculação. Através da palpação retal, realizou-se a avaliação das glândulas vesiculares por ultrassonografia. A análise estatística dos dados foi realizada por meio de análise de variância (ANOVA) para comparação entre médias com nível de significância de 5%. A presença de vesiculite foi observada em 31 animais (73,8%) dos 42 analisados. Dos 31 animais portadores 11 animais (35,5%) apresentaram vesiculite bilateral e 20 apresentaram vesiculite unilateral (64,5%; P<0,05). Animais com perímetro escrotal maior tendem a desenvolver vesiculite unilateral, tal fato pode ser explicado pela precocidade sexual agravado pela sodomia entre os animais. O uso do ultrassom auxilia de forma preventiva a detecção de animais portadores de vesiculite em reprodutores.