Production and composition of milk from female donkeys of the Nordestino Ecotype.

Abstract

This study aimed to determine total production and milk composition of female donkeys of the Nordestino ecotype. A sample of 14 donkey females was used in a completely randomized split-split-plot experimental design in which the plots comprised two groups (primiparous and multiparous females), the split-plots comprised nine evaluation periods, and the split-split-plots comprised the daily evaluation times (every two hours). Total milk production was determined by weighing the foals before and after suckling events. The data were submitted to analysis of variance, means tests, and multivariate principal component analysis. No difference (P > 0.05) was found between the groups regarding milk production, daily evaluation times, pH, or milk contents of lactose, protein, and fat. The donkeys produced on average 5.0 kg milk/day, with the highest mean production around 40 days of lactation. The donkey milk samples had pH close to neutral after the 15th day and protein content progressively decreased over lactation. A negative correlation (r = -56.92; P < 0.0001) was also observed between milk pH and protein concentration. Milk fat content followed a behavior similar to that of protein content, while lactose content differed (P < 0.05) between evaluation days, with the lowest concentration found in colostrum. It is concluded that female donkeys of the Nordestino ecotype produce an average of 5.0 kg milk/day and its composition varies over the first six months of lactation.