Diet supplementation of palm fat powder and coated folic acid on performance, energy balance, nutrient digestion, ruminal fermentation and blood metabolites of early lactation dairy cows
2020
Zhang, Z. | La, S.K. | Zhang, G.W. | Du, H.S. | Wu, Z.Z. | Wang, C. | Liu, Q. | Guo, G. | Huo, W.J. | Zhang, J. | Zhang, Y.L. | Pei, C.X. | Zhang, S.L.
This study investigated the effects of palm fat powder (PFP) and coated folic acid (CFA) supplementation on performance, energy balance, nutrient digestion, ruminal fermentation and blood metabolites in early lactation dairy cows. Thirty-two multiparous Holstein dairy cows were arranged into four treatments in a 2 × 2 factorial randomized block design. Supplemental PFP (0 g/d [PFP−] or 500 g/d [PFP+]) and CFA (0 mg/d [CFA−] or 135 mg/d of folic acid from CFA [CFA+]) were mixed into the top one-third of the daily ration from d 52 prepartum (based on expected calving date) to d 42 postpartum. Dry matter intake was unaltered but milk yield, milk fat content and feed efficiency increased with PFP or CFA supplementation. Milk protein content was not affected by PFP but increased with CFA supplementation. Body weight change was not affected by PFP or CFA supplementation. Energy balance increased with PFP supplementation but decreased with CFA supplementation. Apparent total-tract digestibility of dry matter, organic matter, crude protein, non-fiber carbohydrates, aNDF, ADF and gross energy, ruminal pH and total volatile fatty acids concentration were unchanged with PFP supplementation but increased with CFA supplementation. Ruminal acetate to propionate ratio was decreased by PFP but increased with CFA supplementation. Lower ammonia-N was observed for PFP or CFA supplementation. Activity of α-amylase and population of Butyrivibrio (B.) fibrisolvens and Ruminobacter (Rb.) amylophilu increased but total protozoa decreased with PFP supplementation. Supplementation of CFA increased activity of cellobiase, xylanase, pectinase, α-amylase and protease and population of total bacteria, fungi, protozoa, Ruminococcus (R.) albus, R. flavefaciens, Fibrobacter succinogenes, B. fibrisolvens, Prevotella ruminicola and Rb. amylophilus. Significant PFP × CFA interaction was not observed during the trial. The results indicated that dietary supplementation of PFP or/and CFA had the potential to improve performance of early lactation dairy cows.
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