Effect of parity on the proximate composition and fatty acid profile of milk from Nguni cattle grazing on natural pastures

Abstract

The objective of the study is to establish the effect of parity on milk composition and fatty acid profiles of Nguni cattle milk. Forty-four Nguni cows with parities ranging from 1 to 13 were included in this study. The cows were grouped to three parity groups: parity group 1 (parity 1 to 5), parity group 2 (parity 6 to 9) and parity group 3 (parity 10 to 13). Samples of the milk were collected in a single day and the milk was analyzed using gas chromatography. Parity had no effect of proximate composition (fat, DMC and moisture %) on milk. The fatty acids (FA) present in the milk of the three parity groups were primarily palmitic (33.3 to 40.5%), oleic (16.3 to 20.3%), myristic (12.5 to 13.2%) and stearic (10.8 to 11.7%) acids, in decreasing order of proportion. Milk from parity group 3 cows contained significantly (p < 0.05) higher proportions of butyric, myristoleic, oleic, eicosenoic, conjugated linoleic acid (CLA), arachidonic and eicosopentaenoic acids when compared with the other two parity groups. Parity group 3 also had significantly (p < 0.05) higher values for total SFA, MUFA, PUFA, omega 3 fatty acids and n-6/n-3 ratio than the other two parity groups. Cows in higher parities generally have higher values for individual fatty acids when compared to those in lower parities. Parity is therefore, an important factor that must be considered when assessing milk quality in Nguni cows.

Possibilities of improving fatty acid composition of bovine milk from human health standpoint: a review

“…Some studies noted that parity has a signi cant e ect on the fatty acid composition of bovine milk [38]. In contrast, parity has been reported to signi cantly a ect the contents of many fatty acids in the milk of US dairy cows [27], Nguni cows in South Africa [39], and Canadian Holsteins [27].…”