Abstract
To develop a feeding system to utilize tropical grass for dairy cattle in Okinawa, which is situated in a sub-tropical climate, we fed cattle a total mixed ration (TMR) which included Digitaria eriantha Steud. cv. Transvala hay (Tra group) or imported oat hay (oat group), and compared the effects of both hays on lactation. Both TMRs were based on dry matter, and consisted of 60% self formulation feed and 40% roughage, which consisted of 65% Transvala or oat hay and 35% alfalfa. The nutrient contents were in the following ratios for the Tra and oat groups, 73.0% and 72.0% for total digestible nutrients, 18.2% and 15.8% for crude protein (CP), 39.0% and 35.6% for neutral detergent fiber (NDF), respectively. This study was carried out by the crossover method (2-week period), using eight dairy cattle.
Although the milk yield, fat and protein content and body weight, showed no significant differences between the Tra and oat groups, dry matter intake in the Tra group was significantly lower than the oat group and the concentrations of blood and milk urea nitrogen were significantly higher in the Tra group.
From these results, it was thought that TMR with Transvala hay could replace imported oat hay, if the NDF and CP contents are considered.
