Estimação de parâmetros genéticos para características produtivas em búfalos (Bubalus bubalis) na Amazônia Oriental

Abstract

The objective of this work was to estimate of genetics parameters of dairy buffaloes productive characteristics, such as: milk yield (MY), fat yield (FY), length of lactation (LL) and milk yield per day of calving interval (MYDCI) of buffaloes in the Eastern Amazon. The research was carried through at “Dr. Felisberto Camargo” farm, propriety of EMBRAPA/CPATU, where productive records had analyzed in the period of 1967 until 2005. It had been analyzed a total of 1.182 records of buffaloes females of Murrah breed and its crosses. The observed averages and the standard desviation MY, FY, LL and MYDCI were 1.663, 84 ± 343,60, 116,84 ± 29,71, 269,89 ± 56,36 and 3,88 ± 1,15, respectively. Genetic parameters had estimate by Restricted Maximum Likelihood method in which study the dairy yield of milk and fat were considered permanent effects in the period of birth, genetic group and birth order, besides the dairy yield. The estimate of heritability (h²) to MY, FY, LL and MYDCI were 0.25, 0.18, 0.08 and 0.09 respectively and with coefficients of repeatability (r) for MY, FY e LL of 0.33, 0.29 and 0.10, respectively. The genetic correlations among the characteristics were 0.93 (MY-FY), 0.76 (MY-LL), 0.99 (MY-MYDCI), 0.89 (FY-LL), 0.87 (FY-MYDCI) and -0.27 (LL-MYDCI). There is expresses percentage of animals on the herd studied with higher genetic with relation to medium population for characteristics. In the studied herd, should be considered the additive genetic variability to promote genetic improvement by observing that a majority percentage of the animals are genetically superior to referred characteristics.