Abstract :
A 3-ry study was conducted to determine the performance of midlacatation multiparous and primiparous and primiparous Holstein cows (Bost taurus) fed 3 endophyte-free varieties of tall fescue (Festuca arundinacea Schred)soilage.Cultivars were maintained ina vegetative stage by removel of excess growth.Fortages were Johnstone, kenhy, and Kentckyu-31, (Ky-31) tall fescues.Means for the forage content of crude protein were 14.1,13.3, and 12.8,for Johnstone,Kenhy,and Ky-31,respectively.Concentrations of forage acid detergent and neutral detergent fibers were 30.4 and 60.1,31.2 and 59.9,and 30.9 and 60.4,for Johnstone,Kenhy,and Ky-31 tall fescue varieties,respectively.Soilage from each cultivar was chopped daily and fed individually to 12 cows (average weight of 1128 Ib)in 1986 and 15 cows (average weight of 1242 and 1365 Ib)in 1988 for 6 wk.In addition,cows were fed 20 Ib of a 19,crude protein concentrate daily.No differences were detected in daily forge intake (21.4,22.0,20.7Ib/d),milk production (56.4,56.1,56.71b/d),milk fat percentage (3.38,3.40,3.39,),respiration rate (75.1,71.8,71.1 count of breaths per minute),rectal temperature (10.8,101.8,101.9 F),or serum prolactin (Prl) concentration among cows fed Johnstone,Kenhy,or Ky-31 forage,respectively.Endophyt-free varieties of Johnstone.Kenhy, and Ky-31 appeared to be equal in their ability to support milk production in lactaing dairy cattle.
