Abstract: Whole Crop Corn (WCC), Triticale (WCT) and Barley (WCB) were harvested, chopped and ensiled with urea (15 g kg 1 DM) for 45 days. pH of WCT Silage (WCTS) and WCB Silage (WCBS) was similar, but, significantly differed from WCC Silage (WCCS) (p< 0.05). Crud Protein (CP) (WCCS = 67.2, WCTS = 112.4 and WCBS = 96.4 g kg 1. DM), Non-Protein Nitrogen (NPN), (WCCS = 6/84, WCTS = 16.85 and WCBS = 15.04 mg dL 1) and Neutral Detergent Fiber (NDF), (WCCS = 436, WCTS = 497 and WCBS = 470 g kg 1 DM) were significantly different between treatments (p< 0.05). The results of the incubation of WCCS, WCTS and WCBS using nylon bag technique showed that quickly degradable fraction (a) of Dry Matter (DM) was relatively high for WCTS (0.37±0.01) and intermediate for WCBS (0.32±0.02) and lowest for WCCS (0.24±0.01). Whereas, the slowly fraction (b) for WCTS (0.44±0.02) and WCBS (0.52±0.04) was similar and higher than WCCS (0.54±0.02). The constant fractional rate of degradation (c) of CP for the silages was similar (0.02). In this experiment, the effect of replacing WCCS with WCTS or WCBS on feeding the lactating cows was also investigated. Fifteen Holstein lactating cows (37.1±4.9 kg milk/d) were used in a completely randomized design for 6 weeks. Data were analyzed as repeated measures in time. Cows fed diet containing WCBS had higher feed intake than the cows of the other groups (p< 0.05). Milk yield and component (protein, lactose, Urea Nitrogen (MUN) and total solid milk) were not affected significantly by the treatments. Blood glucose in mid and end of the experiment in each sampling time (0.0 and 4 h) after feeding was not affected by the treatments, but, this metabolite decreased at the 4 h after feeding. Blood Urea Nitrogen (BUN) in the mid the (4 h) and end of the experiment (before feeding) was significantly affected by treatments (p< 0.05).
M. Vatandoost , M. Danesh Mesgaran , R. Valizadeh and H. Nasiri Moghaddam , 2007. Effect of Whole Crop Silages (Triticale or Barley) Versus Corn Silage on Performance of Holstein Lactating Dairy Cows . Journal of Animal and Veterinary Advances, 6: 344-348.