Abstract

The assay aimed to evaluate the effect of feeding a recently developed phytogenic feed additives mixture in diets of lactating Friesian cows (n = 30; 514 ± 10.1 kg body weight) for 3 months. Cows were stratified into three groups of 10 cows each and fed a control diet alone or the control diet supplemented with the additives mixture at 3 g (PHY3) or 6 g (PHY6)/cow daily. Menthol, levomenthol, β-linaloolm, anethole, hexadecanoic acid and p-menthane were the principle compounds identified in the additives mixture. The PHY3 increased (p < 0.01) intake and nutrient digestibility. PHY3 and PHY6 increased (p < 0.01) ruminal pH, total volatile fatty acids, propionate and acetate. PHY3 and PHY6 improved serum total protein and antioxidant capacity and decreased the concentrations of serum urea-N, triglycerides, total lipids, cholesterol and malondialdehyde (p < 0.05). PHY3 increased milk production and milk content of total solids, protein, lactose and fat. Both PHY3 and PHY6 did not affect mineral concentrations in blood or milk. It is concluded that the inclusion of 3 g/cow/d of feed additives mixture in the lactating Friesian cows diet enhanced milk production and feed utilization, with negative effects observed with increasing the dose of additives mixture to 6 g/cow daily.

摘要

该测定旨在评估在哺乳弗里斯兰奶牛（n  = 30；514 ± 10.1 kg 体重）日粮中饲喂最近开发的植物性饲料添加剂混合物3 个月的效果。将奶牛分成三组，每组 10 头奶牛，单独饲喂对照日粮或以每天 3 克 (PHY3) 或 6 克 (PHY6)/奶牛添加添加剂混合物的对照日粮。薄荷醇、左薄荷醇、β-芳樟醇、茴香脑、十六烷酸和对薄荷烷是添加剂混合物中确定的主要化合物。PHY3 增加 ( p  < 0.01) 摄入量和营养消化率。PHY3 和 PHY6 增加（p < 0.01) 瘤胃 pH、总挥发性脂肪酸、丙酸盐和乙酸盐。PHY3 和PHY6 提高血清总蛋白和抗氧化能力，降低血清尿素氮、甘油三酯、总脂质、胆固醇和丙二醛的浓度（p  < 0.05）。PHY3 增加了牛奶产量和总固体、蛋白质、乳糖和脂肪的含量。PHY3 和 PHY6 均不影响血液或牛奶中的矿物质浓度。结论是，在泌乳弗里斯兰奶牛日粮中加入 3 克/奶牛/天的饲料添加剂混合物提高了牛奶产量和饲料利用率，随着添加剂混合物的剂量增加到每天 6 克/奶牛，观察到了负面影响。