Relationship between back and rump fat thickness and residual feed intake of young Nellore cattle / elação entre espessura de gordura subcutânea no lombo e na garupa e consumo alimentar residual em bovinos Nelore jovens
Eimar de Oliveira Lara, Gustavo; Eugênia Zerlotti Mercadante, Maria; Luiz Grion, André; Geraldo Ribeiro, Enilson; Helena Branco, Renata.
B. Indústr. Anim.;
69: 34-34, 2012.
Artigo
em Português
| VETINDEX
| ID: vti-467552
Resumo
Residual feed intake (RFI) is a feed efficiency trait defined as the difference between actual feed intake and the one predicted on the basis of requirements for production and maintenance of body weight. Evidence exists of a positive correlation between RFI and fat thickness in Bos taurus, suggesting that low RFI cattle (feed efficient ones) are leaner. The objective of this study was to access the relationship between fat thickness and RFI by partial correlation including all animals (n=603, 300 bulls and 303 heifers), and by means comparison including only animals divergently classified by RFI (low RFI, n=192 and high RFI, n=186). The animals were born from 2004 to 2010, and were performance tested after weaning for 56 to 112 days, depending of test year and sex. The average age and body weight at the beginning of performance test were 286±42 days and 225±51kg. At the end of performance test images of backfat thickness (BF) were obtained by ultrasound (Pie Medical-Aquila-3.5 MHz linear probe) between the 12th and 13th ribs, transversely over the longissimus muscle. Images of rump fat thickness (RF) were obtained at the junction of the gluteus medius and biceps femoris muscles between the hook and pin bones. The images were saved and subsequently analyzed using Echo Image Viewer 1.0. For partial correlations (MANOVA, SAS 9.3), the model included fixed effect of contemporary gO artigo não apresenta resumo em português.
Biblioteca responsável:
BR68.1
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