EFFECT OF CONCENTRATE FEEDING BEFORE CALVING ON FEED INTAKE, METABOLIC PROFILE AND PERFORMANCE OF EARLY LACTATION COWS

A one-factorial experiment was carried out on 36 Polish Holstein-Friesian cows from 6 weeks before parturition until 8 weeks of lactation. Animals were allotted to 4 groups of 9 animals and fed rations with different protein and energy levels before parturition. Cows from the control group (C) received concentrate with barley (55%) and wheat (13%) and cows from groups W6, W4 and W1 were fed concentrate with sorghum (68%). Cows from group C before parturition and early lactation cows from all groups were fed according to IZ-INRA (2001) standards. In each group, the level of concentrates was increased weekly from 3 to 1 week before parturition and animals received 1, 2 and 2 kg/day (group C) and 1, 2 and 4 kg/day (groups W6, W4 and W1) at 3, 2 and 1 week before parturition, respectively. Additionally, 1 kg of concentrate was fed to cows from group W6 (at 6, 5 and 4 weeks before calving) and those from group W4 (at 4th week before calving). It was found that lengthening the period of feeding concentrate containing 68% of sorghum until 4 and especially 6 weeks before parturition while increasing the energy and protein levels in the ration during the last week before calving, caused the greatest decrease in NEFA and BHBA concentration and the greatest increase in serum glucose concentration and slightly improved milk performance of the cows during the first 8 weeks of lactation. This feeding procedure also reduced the number of semen doses per conception, and the costs incurred for additional concentrate given to the animals in the discussed period were completely compensated by a profit from higher milk production. It may be presumed that prolonging the period of feeding sorghum-containing concentrate until 6 weeks before calving allows the alimentary tract to better adapt to digestion of slowly fermented starch in the rumen and decreases the energy deficit in early lactation cows.