Abstract

An experiment was conducted to measure the effects of feeding Lactobacilli (LAB) with a slow intake urea supplement (SIUS) blended into a probiotic/prebiotic mixture, fed at pre partum and early post-partum, using 84 Jersey cows. Two integrated diets (ID), pre and postpartum, were fed to two groups of 42 cows: first, pre partum starting 21 d before calving as follows: 1) ID without supplement 2) ID with LAB/SIUS; Second, post calving cows (20 animals each) were fed a lactation diet (LD) T1 with LAB/SIUS pre and postpartum, T2 LAB/SIUS only prepartum, T3 LAB/SIUS only postpartum and T4 without LAB/SIUS supplementation. LAB probiotic supplementation contained approximately 4x107 cfu of lactic acid bacteria composed of 4x106cfu of Lactobacillum plantarum; 10x106cfu of Lactobacilum delbrueckii; 8x106cfu L. helveticus; 10x106cfu Lactococcus lactis; 10x106cfu Leuconostoc mesenteroides; and 5x104cfu of Bifidus spp. mixed into a liquid 250g supplement/cow per d in both pre partum and post-partum periods. SIUS composition was: 17% corn, 17% molasses, 16% poultry litter, 14% rice polishing, 8% cottonseed meal, 5% lard, 4% fish meal, 4% salt, 4% urea, 3.2% calcium carbonate, 3% orthophosphate, 2.2% ammonium sulfate, 1.6% cement kiln dust and 1% mineral salt. DMI, milk yield, and milk protein content were higher for cows receiving the LAB/SIUS probiotics compared with the LAB/SIUS diet (P<0.05). Blood glucose, insulin levels, plasma nonesterified fatty acids (NEFA) and BHBA were higher suggesting that LAB/SIUS supplementation increased DMI and milk production due to more glucose available when administrated continually, with an intermediate metabolic response when LAB/SIUS was given only pre or postpartum. Blood metabolite information suggested that the response was associated with more glucose being made available and fewer fatty acids being mobilized from lipid stores. Purines were significantly increased with the LAB/SIUS diet (P<0.05). Adding a probiotic to the diet augmented DMI probably from a higher rumen cell wall utilization and development of bacterial protein from non-protein nitrogen.

Keywords: Probiotics;Lactobacilli; Milk production;Cows;Supplementation;Blood parameters;Rumen parameters