Body external components and discard fat of feedlot finished Charolais x Nellore crossbred cows slaughtered with different weights

Revista Brasileira de Zootecnia

Brondani, Ivan Luiz³  Restle, João²  Leite, Daniel Terra³  Menezes, Luís Fernando Glasenapp de³  Pascoal, Leonir Luiz³  Kuss, Fernando¹  Santos, Maurício Fernandes dos³ 

[1] UFRGS;UFG, Goiânia;UFSM

关键词: beef cattle;    crossbreeding;    fat tissue;    females;    limbs;    skin    Introdução Nos últimos anos;    tem-se enfatizado o estudo dos componentes não-carcaça;    como conseqüência da valorização dos órgãos aptos ao consumo;    do couro e dos resíduos usados pela indústria de rações e;    principalmente;    por esses componentes estarem associados ao rendimento de carcaça;    quando são mais pesados;    o rendimento tende a ser menor;    diminuindo o valor da carcaça;   

DOI  :  10.1590/S1516-35982007000400016

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

The objective of this experiment was to study the development of external body components and that of discarded fat in feedlot finished crossbred cows from the second (G2 - 3/4Charolais (C) 1/4Nellore (N) and 3/4NC) and third (G3 - 5/8CN and 5/8NC) generations of a Charolais ´ Nellore rotational crossbreeding program slaughtered with 465 (T465), 507 (T507) and 566 kg (T566) of body weight. At the beginning of the trial, age, body weight and body condition score averaged, respectively, 8.5 years, 388.6 kg and 2.35 points. Animals were fed a diet with a forage to concentrate ratio of 48:52, which contained 12.5% of CP and 2.99 Mcal of digestible energy per kg of DM. The increment in empty body weight (EBW) (376.34, 412.53 e 463.64 kg, respectively, for T465, T507 and T566) followed that of slaughter weight (SW) but EBW yield did not change and averaged 81.51% across the different SW groups. Increased SW and EBW reduced the proportion of digesta content. Animals with heavier body weight showed greater development of head and udder. However, skin growth was not affected leading to lower relative proportion with the increase of SW and EBW. Increasing SW also resulted in lower relative participation in the EBW of the external components (16.47, 15.65 and 14.30%). Deposition of internal fat increased until T507 while that of subcutaneous fat was greatest on T566, resulting in larger removal of trim fat from carcasses of T566 (4.02, 4.26 and 7.31 kg, respectively) cows. Greater participation of Charolais in the genotype resulted in higher head development. Cows of the third generation of the rotational crossbreeding Charolês ´ Nellore had greater head size than those from the second generation (16.22 against 15.77 kg).

【 授权许可】

CC BY-NC