| Texto completo | |
| Autor(es): |
Yokoo, M. J.
[1, 2]
;
Lobo, R. B.
[3, 4]
;
Araujo, F. R. C.
[2]
;
Bezerra, L. A. F.
[3]
;
Sainz, R. D.
[5]
;
Albuquerque, L. G.
[1]
Número total de Autores: 6
|
| Afiliação do(s) autor(es): | [1] Sao Paulo State Univ, Dept Anim Sci, BR-14884900 Sao Paulo - Brazil
[2] Aval Serv Tecnol SS, Uberaba, MG - Brazil
[3] Univ Sao Paulo, Dept Genet, Sao Paulo - Brazil
[4] Natl Assoc Breeders & Researchers Ribeirao Preto, Sao Paulo, Ancp - Brazil
[5] Univ Calif Davis, Dept Anim Sci, Davis, CA 95616 - USA
Número total de Afiliações: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF ANIMAL SCIENCE; v. 88, n. 1, p. 52-58, JAN 2010. |
| Citações Web of Science: | 44 |
| Resumo | |
The aim of the present study was to evaluate the genetic correlations among real-time ultrasound carcass, BW, and scrotal circumference (SC) traits in Nelore cattle. Carcass traits, measured by real-time ultrasound of the live animal, were recorded from 2002 to 2004 on 10 farms across 6 Brazilian states on 2,590 males and females ranging in age from 450 to 599 d. Ultrasound records of LM area (LMA) and backfat thickness (BF) were obtained from cross-sectional images between the 12th and 13th ribs, and rump fat thickness (RF) was measured between the hook and pin bones over the junction between gluteus medius and biceps femoris muscles. Also, BW (n = 22,778) and SC ( n = 5,695) were recorded on animals born between 1998 and 2003. The BW traits were 120, 210, 365, 450, and 550-d standardized BW (W120, W210, W365, W450, and W550), plus BW (WS) and hip height (HH) on the ultrasound scanning date. The SC traits were 365-, 450-, and 550-d standardized SC (SC365, SC450, and SC550). For the BW and SC traits, the database used was from the Nelore Breeding Program-Nelore Brazil. The genetic parameters were estimated with multivariate animal models and REML. Estimated genetic correlations between LMA and other traits were 0.06 (BF), -0.04 ( RF), 0.05 (HH), 0.58 (WS), 0.53 (W120), 0.62 (W210), 0.67 (W365), 0.64 ( W450 and W550), 0.28 (SC365), 0.24 (SC450), and 0.00 ( SC550). Estimated genetic correlations between BF and with other traits were 0.74 ( RF), -0.32 (HH), 0.19 (WS), -0.03 (W120), -0.10 (W210), 0.04 (W365), 0.01 (W450), 0.06 ( W550), 0.17 (SC365 and SC450), and -0.19 (SC550). Estimated genetic correlations between RF and other traits were -0.41 (HH), -0.09 (WS), -0.13 ( W120), -0.09 ( W210), -0.01 ( W365), 0.02 (W450), 0.03 (W550), 0.05 ( SC365), 0.11 ( SC450), and -0.18 (SC550). These estimates indicate that selection for carcass traits measured by real-time ultrasound should not cause antagonism in the genetic improvement of SC and BW traits. Also, selection to increase HH might decrease subcutaneous fat as correlated response. Therefore, to obtain animals suited to specific tropical production systems, carcass, BW, and SC traits should be considered in selection programs. (AU) | |
| Processo FAPESP: | 05/58113-9 - Estimativas de parametros geneticos das caracteristicas de carcaca, medidas pela ultra-sonografia, de crescimento e reproducao em bovinos da raca nelore. |
| Beneficiário: | Marcos Jun-Iti Yokoo |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |