Author(s)

Xueyan Lin, Guimei Liu, Zhengyan Yin, Yun Wang, Qiuling Hou, Kerong Shi, Zhonghua Wang^*

College of Animal Science and Technology, Shandong Agricultural University, Tai’an, China.

The present study investigated the effects of the supplemental dietary energy source on early lactating cows in a positive energy balance. Cows in the control group were fed a basal total mixed ration containing high-quality hay as forage, and the dietary concentrate to forage ratio was 45:65. The corn supplementation resulted in a significant decrease in the milk fat content (P < 0.05) and a low milk fat yield (P = 0.15), whereas the fat supplementation resulted in a decreasing trend of the milk protein and lactose content (P ≤ 0.1). Additionally, the corn supplementation significantly decreased the serum 5-hydroxytryptamine level (P < 0.05). The results support the proposal that the source of supplemental dietary energy has varying effects on feed intake, lactation performance, and the intermediate metabolism of early lactating cows in a positive energy balance. 5-Hydroxytryptamine secretion may be associated with the varying effects of the source of supplemental dietary energy.

Dairy Cow, Lactation, Energy Source, 5-Hydroxytryptamine

Lin, X. , Liu, G. , Yin, Z. , Wang, Y. , Hou, Q. , Shi, K. and Wang, Z. (2017) Effects of Supplemental Dietary Energy Source on Feed Intake, Lactation Performance, and Serum Indices of Early-Lactating Holstein Cows in a Positive Energy Balance. Advances in Bioscience and Biotechnology, 8, 68-77. doi: 10.4236/abb.2017.82005.