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O estudo foi realizado com objetivo de avaliar os efeitos da condição sexual nos pesos e rendimentos dos não constituintes da carcaça de cordeiros cruza Texel x Corriedale. Foram utilizados 46 machos divididos em três grupos: não castrados (n=15), castrados (n=17) e induzidos ao criptorquidismo (n=14). Foi adotado o delineamento experimental inteiramente casualizado com três tratamentos e número variável de repetições. Foi realizada análise de variância para avaliar o efeito da condição sexual sobre as características estudadas. Cordeiros castrados atingiram as condições estipuladas para o abate mais precocemente. Não castrados e induzidos ao criptorquidismo apresentaram pesos superiores de cabeça (kg), pele (kg), pênis (kg) e fígado com vesícula (kg). Não castrados apresentaram valores superiores do conjunto pulmões com traqueia (kg) em relação a animais castrados. Conclui-se que cordeiros não castrados e induzidos ao criptorquidismo apresentam pesos superiores de alguns componentes corporais quando terminados em campo nativo recebendo suplementação de 1% do peso corporal. Proporcionalmente, a condição sexual não interfere nos rendimentos dos componentes corporais de cordeiros Texel x Corriedale.Palavras-chave: Castração; componentes corporais; indução ao criptorquidismo; Ovis aries.

The objective of this work was to identify relationships of the body mass index (BMI) with the body energy reserves and tissue composition of shoulder and leg cuts of Corriedale lambs. Twenty-two sheep with average age of 18 months were used. Linear regressions were determined between the studied characteristics. The mean body mass, body condition score (BCS), and BMI were 49.09±7.8 kg, 2.69±0.81, and 10.66±0.99, respectively. The BMI was correlated with the BCS (r = 0.51) and internal fat (r = 0.81). Multiple linear equations, involving BMI and BCS, yielded correlation coefficients between 0.50 and 0.76, with significant values for all studied characteristics. The body mass index allows estimating the body energy reserves of Corriedale sheep.

This study was intended to evaluate body size structure and growth parameters of crossbred heifers fed at four nutritional levels to achieve puberty earlier. Animals were classified depending on their level of crossing between Nelore and Hereford and subjected to four nutritional levels (kg day−1) as follows: 0.5 (light; n = 32), 0.75 (medium; n = 32), 1.00 (high; n = 29), and 1.25 (very high; n = 27). Heifers at puberty and at weaning were individually classified for growth parameters. The fat thickness and longissimus muscle area throughout the experimental period were determined by ultrasonography. The height, heart girth, frame, and weight:height ratio were variables used to evaluate body traits. Univariate analysis of variance using the GLIM MIXED procedure os SPSS was performed and the significance level was set at 0.05. Age and body weight at puberty were 388±1.9 days and 331.4±1.3 kg, respectively. Body condition score demonstrated an interaction between nutritional level and crossbred degree. Heifers with the highest degree of Nelore had higher fat thickness and lower weight:height ratio compared with other racial groups at puberty. Pearson correlation coefficient showed a negative association for body condition score (−0.34) and fat thickness (−0.58) compared with age at puberty. The increased fat thickness at younger ages at puberty was observed in all racial groups. The increased weight:height ratio at younger ages at puberty was observed in all racial groups. We observed higher values for a frame in animals at the higher level of supplementation. There is a greater correlation between live weight gain and phenotypic traits during weaning to achieve puberty at an earlier age in crossbred heifers.