Kafkas Üniversitesi Veteriner Fakültesi Dergisi 2019 , Vol 25 , Issue 5
Effects of Exogenous Amylase in Transition Dairy Cows Fed Low-Starch Diets: 2. Total Tract Digestibility and Blood Urea Nitrogen
Hıdır GENÇOĞLU1, Çağdaş KARA1, Mukaddes Merve EFİL1, Hakan BİRİCİK1, İbrahim İsmet TÜRKMEN1, Gülay DENİZ1, Arda KOVANLIKAYA1, Randy Duncan SHAVER2, Recep Tolga KIVANÇ1, Ramazan YILDIRIM1
1Department of Animal Nutrition and Nutritional Diseases, Faculty of Veterinary Medicine, Bursa Uludag University, TR-16059 Bursa - TURKEY
2Department of Dairy Science, University of Wisconsin - Madison, 1675 Observatory Dr. Madison 53706, USA
DOI : 10.9775/kvfd.2018.21401 The objective of this trial was to determine the effect of exogenous amylase during the transition period on total tract digestibility, rumen pH and blood urea nitrogen in lactating dairy cows. The effect of exogenous dietary amylase supplementation on lactation diets with low starch concentration (19.5% of dry matter) and dry period diets with moderate starch concentration was evaluated (15.5% of dry matter). A total of 30 multiparus Holstein cows were randomly assigned to two groups with amylase (n=15) or control (n=15). Three cows from each group were randomly selected and ruminally cannulated for digestibility trials. The research was conducted starting at 21 d prepartum until 84 d postpartum. Digestibility of dry matter, organic matter, neutral detergent fiber, starch, and crude protein remained unaffected by treatment in postpartum. Average pre- and postpartum rumen pH concentrations were 6.25 and 6.15, respectively, and did not differ between treatments. Blood urea nitrogen (BUN) concentrations were lower in cows fed amylase supplemented diet compared to those fed diet without amylase in both pre- and postpartum periods (P<0.001). In conclusion, the dietary supplementation of amylase did may not affect the digestibility of nutrients, however, it may decrease the BUN concentration in pre- and postpartum period for cows fed amylase. Therefore, it may offer potential for improving nitrogen efficiency in dairy cows. Keywords : Amylase, Starch, Total tract digestibility, Blood urea nitrogen, Dairy cows