Authors : Tong Qin, Haoyu Wang, Dengpan Bu, Haisheng Hao, Dong Wang, Weihua Du and Huabin Zhu
Abstract: The objective of this study was to evaluate the effect of a corn straw or mixed forage diet on endocrine, metabolism and lactation performance in periparturient Holstein cows. Twelve multiparous, periparturient Holstein cows were randomly assigned to two groups and fed a corn straw or mixed forage diet, respectively. The CS diet included 33.8% corn straw and the F:C ratio [Dry Matter (DM)] was 60:40. The MF diet included 3.7% Chinese wildrye, 28.4% alfalfa hay and 26.5% corn silage, the F:C ratio (DM) was 40:60. All cows were fed from weeks 3-8 and Body Weight (BW), Body Condition Score (BCS) and Dry Matter Intake (DMI) were recorded. Milk protein, fat, lactose and Somatic Cell Count (SCC) were determined twice weekly. Metabolite and hormone analyses of blood were made weekly. Results showed that dietary treatments had no detectable effects on BW, BCS, DMI and blood hormones measured. From the 6 weeks of lactation, cows fed MF diet produced more milk (p<0.05) and tended to produce more milk fat (p = 0.07) and protein (p = 0.10) compared with cows fed CS diet. The proportions of milk fat, protein and lactose (%) did not differ between the two dietary treatments (p>0.05). In addition, the milk SCC in the CS group was significantly higher (p = 0.02) than the MF group. Cows fed MF diet experienced more severe Negative Energy Balance (NEB) and had higher concentrations of β-Hydroxy Butyric Acid (BHBA) and Non-Esterified Fatty Acid (NEFA) than cows fed CS diet. Collectively, these results suggest that cows fed MF diet improve lactation performance of periparturient cows but this dietary treatment may have an adverse effect on NEB of periparturient cows.
Tong Qin, Haoyu Wang, Dengpan Bu, Haisheng Hao, Dong Wang, Weihua Du and Huabin Zhu, 2013. Effect of a Corn Straw or Mixed Forage Diet on Endocrine, Metabolism and Lactation Performance in Periparturient Cows. Journal of Animal and Veterinary Advances, 12: 276-282.