Changes in the composition of goat colostrum and milk fatty acids during the first month of lactation

Abstract

Changes in the composition of colostrum and milk fatty acids during the first month of lactation of ten 3-years-old White shorthaired goats fed a winter diet were investigated. Thirty-eight fatty acids (FAs) were identified in the milk fat. Saturated FAs accounted for 67.0% of the total determined FAs in colostrum and 62% at 30 days post partum. Monounsaturated FAs made up 28.2% of the total FAs in colostrum and increased with the progress of lactation at the expense of saturated FAs. The percentage of polyunsaturated FAs varied from 4.4 to 4.8%. The major FAs in colostrum and milk were palmitic and oleic acids, followed by stearic and myristic acids (30.1, 25.3, 11.8, 11.4% and 23.6, 30.3, 13.6, 8.6% in colostrum and milk 30 days post partum, respectively). The levels of palmitic and myristic acids in colostrum were higher than in mature milk, whereas the levels of capric, stearic and oleic acids were lower. The medium-chain FA (caprylic, capric, lauric) content increased from 8.7% of FAs in colostrum to 11.1% on the fourth day of lactation. These acids are efficient antimicrobials, thus may contribute to the protection of young goats from microbial pathogens.