REPRODUCTIVE PARAMETERS FOR HOLSTEIN-FRIESIAN CATTLE IN FREE-STALL IN THE CENTRE WEST OF BRAZIL

• Autor(a) principal: McManus, Concepta
• Data de Publicação: 2008
• Outros Autores: Louvandini, Helder, Falcão, Rui Arruda, Garcia, José Américo Soares, Saueressig, Moacir Gabriel
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Ciência animal brasileira (Online)
• DOI: 10.5216/cab.v9i2.4222
• Texto Completo: https://revistas.ufg.br/vet/article/view/4222
• topic: Reprodução de bovinos

The objective of the present study was to estimate the effect of fixed effects on production traits as well as genetic parameters, including heritabilities and repeatability. In total, 1255 registers were analyzed for mortality (MORT), 774 registers for calving interval (CI), 1255 registers for gestation length (GL), 402 registers for first calving age (FCA) and 3344 registers for insemination success (P). The data were collected at the CESIPL (Experimental Centre for Intensive Milk Production System) located on the road DF-100, Colônia Agrícola Itapeti, Distrito Federal - Brazil. The averages and the respective standard deviations for each reproductive trait were: MORT 0.02396 (0.15); CI 413.45 (94.58) days; GL 275.25 (6.87) days; FCA 1493.23 (690.69) days; PRE 0.46 (0.47). The value for difficult calving percentage (DC) was 3.875 % (0.19) and average calf birth weight (BW) was 39.17 kg (6.69). The effects of month and year of calving, degree of purity, sex, calving order, birth weight and type of birth were investigated as appropriate for each trait. The respective heritability coefficients for CI, PG, FCA and P were 0.18; 0.07; 0.13; and 0.24. The respective coefficients of repeatability for CI, PG and P were 0.13; 0,45x10-1; and 0,15x10-6. Thus, the coefficients for heritability and repeatability for reproductive parameters are low therefore unlikely to respond well to selection.  KEY WORDS: Correlations, genetic parameters, heritability, repeatability.