| Full text | |
| Author(s): |
Stefani, Gabriela
[1]
;
Aquaroli, Daniele Brandao
[2]
;
Costa Junior, Joao Batista Goncalves
[3]
;
Santana Junior, Mario Luiz
[4]
;
Tonhati, Humberto
[1]
;
Sesana, Roberta Cristina
[5]
;
El Faro, Lenira
[2]
Total Authors: 7
|
| Affiliation: | [1] Fac Ciencias Agr & Vet Unesp, Zootecnia, Campus Jaboticabal, BR-14884900 Jaboticabal, SP - Brazil
[2] Ctr Pesquisas Bovinos Corte, Inst Zootecnia, Sertaozinho - Brazil
[3] Fac Patos de Minas, Patos De Minas - Brazil
[4] Inst Ciencias Agr & Tecnol UFMT, Grp Melhoramento Anim Mato Grosso, Rondonopolis - Brazil
[5] CRV Lagoa, Gestor Leite, Sertaozinho - Brazil
Total Affiliations: 5
|
| Document type: | Journal article |
| Source: | JOURNAL OF APPLIED ANIMAL RESEARCH; v. 49, n. 1, p. 1-5, JAN 1 2021. |
| Web of Science Citations: | 1 |
| Abstract | |
The present study aims to estimate genetic parameters for dystocia, milk yield and age at first calving of Holstein cows reared in intensive production systems located in the southeastern region of Brazil. A total of 26,987 first-lactation records of Holstein cows were used. The following traits were analysed: 305-day cumulative first lactation milk yield (MY305), age at first calving (AFC) and dystocia. Dystocia was defined as a binary trait, with 0 indicating failure and 1 indicating success. Success was attributed to cows that had a normal calving, and failure was attributed to cows that had a difficult or human-assisted parturition. The (co)variance components were estimated using a Bayesian approach. The heritability estimates were 0.15 (0.01), 0.27 (0.02), and 0.17 (0.03) for MY305, AFC and dystocia, respectively. Dystocia showed genetic correlations of 0.30 (0.09) with AFC and -0.17 (0.11) with MY305. Early maturing heifers may be genetically prone to a more difficult first calving. (AU) | |
| FAPESP's process: | 10/05697-1 - Multi-trait random regressiom models for milk yield and milking speed of dairy cattle |
| Grantee: | Lenira El Faro Zadra |
| Support Opportunities: | Regular Research Grants |