Association between genetic evaluation and show-ring judging for dairy and beef cattle

Abstract

SummaryBackground: a concern for breeders is whether an animal ranking based on genetic evaluations is similar to that obtained from show-ring judging. Objective: to determine the association between rankings for Braunvieh (BR) and Brown Swiss (BS) cattle of Mexico based on show-ring judging and their respective expected progeny differences (EPDs) or predicted transmitted abilities (PTAs). Methods: ranking values from judging were transformed using the rankit transformation. For each breed, Pearson correlation analyses were performed between the transformed rank values of the animals obtained from judging at the show-ring and their EPD or PTA values. Results: using the complete databases, in both breeds the correlation coefficient estimates were low (<0.18) but different from zero (p<0.05). The correlation coefficient considering PTAs for milk yield in BS was slightly higher than those obtained for any EPD for growth traits in BR. Correlations in adult animals (0.18 to 0.23) were different from zero (p<0.05) and higher than those of young animals or calves, while those within males or females were similar. Correlations within years of judging in the show-ring were variable and did not indicate any specific trend. Conclusions: show-ring rank results are associated with genetic evaluation of animals, although the magnitude is low. Selection of breeding animals based on show-ring judgment could be used as a complementary tool to genetic evaluation.

Impacto de las evaluaciones genéticas en las tendencias genéticas de bovinos Jersey y Suizo Americano en México

“…A pesar de que las EG presentan ventaja ante la evaluación visual, la cual oculta efectos ambientales diferentes entre animales (Ramírez-Valverde et al, 2016), en México aún existe una cultura de seleccionar animales por características fenotípicas externas, arraigadas a prácticas del pasado que limitan el uso de las EG. En JE se documentó que el criterio de selección (o compra) de reproductores contempla características de conformación externa (Larios-Sarabia et al, 2011).…”

“…ISSN 2007 -0705, pp. : 1 -24 -13 -tiene una asociación con los resultados de las EG nacionales, esta relación es de baja magnitud, por lo que la selección de animales por su apariencia externa se recomienda sólo como una herramienta complementaria a la selección con base en las EG (Ramírez-Valverde et al, 2016).…”

“…ISSN 2007 -0705, pp. : 1 -24 -20 -y utilizar las características fenotípicas externas únicamente como herramienta complementaria (Ramírez-Valverde et al, 2016); además, sobre cómo seleccionar los animales importados para sus hatos (Ramírez-Valverde et al, 2014b), y, sobre todo, concientizarlos sobre el papel que juegan como ganaderos de registro en el mejoramiento genético de la ganadería del país (Larios-Sarabia et al, 2011).…”