Effect of Feeding Bypass Fat Supplement on Milk Yield, Its Composition and Nutrient Utilization in Crossbred Cows
Tyagi Nitin1, Thakur S.S.2, Shelke S.K.
Dairy Cattle Nutrition Division, National Dairy Research Institute, Karnal-132 001 (Haryana) India
1Punjab Agricultural University, Ludhiana, Punjab
2Corresponding author: Tel: 0091-184-2259062; Mobile: 0091-9416484247; Fax: 0091-184-2250042, E-mail: firstname.lastname@example.org
Effect of feeding bypass fat supplement during the first quarter of lactation on milk production was studied on nineteen crossbred cows divided in two groups and fed wheat straw; green maize and concentrate mixture as per requirements (9 cows, most probable production ability (MPPA) 3441.32 kg, 2–4 lactation) in control group (G1) and the same ration along with 2.5% bypass fat of total DMI (10 cows, MPPA 3457.2 kg, 2–4 lactation) in treatment group (G2). The cows of G2 group were supplemented bypass fat 40 days pre partum till 90 days post partum and carry over effect of supplementation on milk production was monitored up to 210 days of lactation. The average milk yield during supplementation period in G2 was higher (P<0.05) than that of G1, being 18.65 and 17.57 kg/d, respectively. Similarly, the milk yield during the carry over period was higher (P<0.05) in G2 than that of G1, being 14.81 and 13.79 kg/d, respectively. Similar trend was also recorded for FCM yield in the two groups. The DM and CP was better utilized (P<0.05) for milk production in G2 as compared to G1. There was no difference in milk composition while the average fortnightly milk urea nitrogen (MUN) was lower (P<0.05) in G2 as compared to that of G1. Total unsaturated fatty acids (as % of total FA) in G1 were 32.49, 32.03 and 31.52 per cent in early, mid and late lactation, whereas corresponding values in G2 were 41.36, 38.00 and 38.29 respectively, showing an increase of 27.3, 18.6 and 21.5 in G2 over that of G1. The total long chain fatty acids (LCFA) and monounsaturated fatty acids (MUFA) content were higher in G2 as compared to that of G1 throughout the experimental period. NEFA concentration in blood was 106.54 and 124.12 mg/l and Plasma triglyceride concentrations were 18.78 and 18.15 mg/dl in G1 and G2, respectively. It could be concluded from the present study that bypass fat supplementation @ 2.5 per cent of DMI increased the milk production, proportion of unsaturated FA and LCFA in milk fat and persistency of lactation of high yielding crossbred cows.
Bypass Fat, Milk Production, Crossbred Cows, Milk Fatty Acids and blood profile.