Brazilian Sport Horse: genetic parameters for approval of Brasileiro de Hipismo stallions.
Trop Anim Health Prod
; 52(4): 1669-1680, 2020 Jul.
Article
em En
| MEDLINE
| ID: mdl-31858372
The aim of this study was to evaluate genetic parameters for subjective scores given at the Brazilian Sport Horse (BSH) Stallion Approval by estimating heritability (h2) for morphological, gait, and jumping traits and genetic correlations (γg) among the functional ones and by verifying selection feasibility. The analysis included 1179 complete evaluations from 294 horses, by 4.26 ± 0.96 judges. Each trait was evaluated using mixed models in SAS® v9.2, considering the individual as a random effect. Variance components and genetic parameters were obtained by single and two-trait animal models in a derivative-free restricted maximum likelihood analysis. Since many jumping traits were not described in Breed Regulation, mixed model results were used to enlighten the criteria adopted in the assignment of scores. Balanced bodies and conformations that favor collection were preferred by judges and presented moderate heritabilities. Additive variation was found for most jumping traits, with heritability equal to 0.74 (se = 0.04) for overall jump, and estimates for the separate aspects of the jump movement ranging from near null to 0.43 (se = 0.07) for temperament. Morphological scores had little effect over gait and jump scores while trot may be indicative of some additive value for jump distance and canter for hind limb mechanics. Conformation evaluations of separate body regions presented heritability estimates similar to previous studies and may provide more informative breeding values.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Marcha
/
Cavalos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
País/Região como assunto:
America do sul
/
Brasil
Idioma:
En
Revista:
Trop Anim Health Prod
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos