Evaluation of Feeding Dairy Cow with Whole Wheat Hay and Alfalfa

The preliminary results of this laboratory (unpublished) indicate that the nutritional value of whole wheat hay (wheat hay, for short) is very high, and the milk stage is the best period of wheat hay harvest. In this study, we investigated the feeding effect and economic benefits using wheat hay instead of alfalfa diet for dairy cows under the condition of the same energy and crude protein levels. Three types of diets were used: alfalfa diet, wheat hay diet and alfalfa + wheat hay diet. The results showed that the dry matter digestibility of alfalfa diet and alfalfa + wheat hay diet did not differ significantly (P > 0.1), but was significantly higher than that of wheat hay diet (P < 0.05). The wheat hay diet could produce more propionic acid and ammonia nitrogen (P < 0.05) in the rumen, and reduce the ratio of acetic/propionic and nitrogen utilization. There was no significant difference in milk production among the three diets (P > 0.1). There was no significant difference in milk somatic cell count and body condition score among the three groups (P > 0.1). The wheat hay diet could significantly increase milk protein and lactose (P < 0.01). The contents of interleukin-6 in cows fed alfalfa diet and alfalfa + wheat diet were significantly higher than that in cows fed wheat hay diet (P < 0.05). There was no significant difference in interleukinm-6 between in cows fed alfalfa diet and alfalfa + wheat diet (P > 0.05). The use of wheat hay to replace imported alfalfa in whole or in part could save feed costs. Full substitution of alfalfa with wheat hay could have a daily economic benefit of 13.74 yuan.