Body condition score and milk fatty acid composition in early lactation of Czech Fleckvieh cows

Abstract

The development of body condition score (BCS) and milk fatty acid composition and its mutual relationships were evaluated in the first 4 weeks of lactation of 50 Czech Fleckvieh cows. Average BCS values ranged from 4.14 at calving to 3.6 points in the 4th week of lactation. The percentage of saturated fatty acids (SFA) tended to slightly increase (69.1 to 71.3%), whereas the percentage of unsaturated fatty acids (UFA) tended to decrease (30.9 to 28.7%). The animals used were divided to three groups according to the BCS change between calving and week 4 of lactation. The cows with a minimum BCS loss during the first 4 weeks postpartum (–0.03 points) showed higher (+2.16 to 5.24%; P < 0.05) SFA proportions than those having BCS loss more than 1 point. An opposite tendency was observed for UFA, with the highest (+1.23 to 5.26%; P < 0.05) proportion found in the animals with the greatest BCS loss (≥ 1 point). These results indicate that high proportions of milk UFA related with a deep negative energy balance expressed by the highest BCS loss (≥ 1 point). The correlations between BCS at calving, BCS in the 1st and 2nd week of lactation, and proportion of fatty acid groups determined in the 4th week ranged from r = 0.29 to r = 0.41 (P < 0.05).