INFLUENCE OF GRAZING PERIOD ON MILK FATTY ACIDS COMPOSITION IN AKKARAMAN EWE AND HAIR GOAT
K. Cebi1*and S. Ozyurek 2
1 Department of Nutrition and Dietetics, Faculty of Medicine, Erzincan Binali Yildirim University, Erzincan, Turkey
2Veterinary Department, Cayirli Vocational School, Erzincan Binali Yildirim University, Erzincan, Turkey
*corresponding author’s e-mail:sozyurek@erzincan.edu.tr
ABSTRACT
The present study aims to determine the seasonal change of fatty acid composition in pasture period, especially CLA (Conjugated linoleic acid), in the milk of Akkaraman ewe and Hair goat. During the pasture period, 10 Akkaraman ewe and 10 Hair goats were grazed only on pasture without additional feeding. Individual milk samples were obtained from each animal once a month from May to October. Plant samples were again obtained from the pasture once a month. The pasture period displayed effects on the CLA ratio in total milk fat acid in both species. CLA had the highest level of total milk fat acid in both species in May when pasture had the highest PUFA, especially linoleic acid (C18:2n6) and α-linolenic acid (C18:3n3). SFA: UFA ratio reached the highest level in June for Akkaraman sheep and Hair goat. Although the atherogenic index was at the lowest level in September (P<0.01) in Akkaraman sheep milk, Hair goat milk had the lowest atherogenic index in May (p <0.001). All Δ9 desaturase activities in Akkaraman sheep milk (14:1/14, 16:1/16 and 18:1/18) were affected by the pasture period. The findings of the present study indicated a relationship between CLA ratio in the total milk fatty acid and C18:3n3ratio in pasture.
Key words: Sheep milk; milk fatty acid; CLA; pasture fatty acid; goat milk. |