玉米-扁豆型青贮饲料对奶牛生产性能和养分消化的影响

Effects of corn-lentil silage on performance and nutrient digestion of dairy cows

本研究评估了玉米-扁豆混合青贮饲料相对于玉米青贮饲料的发酵特性和营养价值。试验以4头带有瘤胃瘘管的荷斯坦奶牛为研究对象,评估了玉米-扁豆混合饲料的瘤胃消化动力学和瘤胃养分降解率。此外,饲养试验选择72头泌乳期的荷斯坦奶牛,随机分为2组,每组36头。两种饲料精料和粗饲料比例为60:40,其中玉米青贮饲料和玉米-扁豆混合青贮饲料占各日粮的24%,粗饲料(苜蓿草)占35.8%。结果:与玉米青贮相比,玉米-扁豆混合青贮料的乳酸和乙酸浓度更高(P<0.05)。玉米-扁豆混合青贮料中干物质、粗蛋白质、粗灰分、钙和粗脂肪含量较青贮玉米组分别显著提高1.04%、0.45%、0.87%、0.25%和0.34%(P<0.05),而中性洗涤纤维和酸性洗涤纤维含量较青贮玉米分别显著降低12.78%和7.57%(P<0.05)。与玉米青贮相比,玉米-扁豆混合青贮的瘤胃干物质、粗蛋白质、中性洗涤纤维和酸性洗涤纤维降解性显著提高(P<0.05)。与玉米青贮饲料相比,玉米-扁豆青贮饲料组奶牛干物质、粗蛋白质、中性洗涤纤维和酸性洗涤纤维表观消化率分别显著提高7.67%、7.84%、5.18%和8.54%(P<0.05)。在60 d试验期内,饲喂玉米-扁豆混合青贮料的奶牛产奶量比玉米青贮料组平均产奶量高3.02 kg/d(P<0.05),同时乳蛋白也显著提高(P<0.05)。综上所述,与青贮玉米相比,玉米-扁豆混合青贮料提高了青贮饲料发酵特性和营养价值,同时,用玉米-扁豆混合料饲喂奶牛可以提高奶牛养分表观消化率、产奶量和乳蛋白。

The fermentation characteristics and nutritional value of corn-lentil mixed silage were evaluated.Four Holstein cows with rumen fistulas were studied to evaluate the rumen digestion kinetics and rumen nutrient degradation rate of corn-lentil mixed feed.In addition,for the feeding experiment,72 Holstein cows with lactation were selected and randomly divided into two groups of 36 cows.The ratio of feed concentrate to rouse was 60:40,of which corn silage and mixed corn and lentil silage accounted for 24%of each diet and rouse(alfalfa)35.8%.Results:compared with corn silage,the lactic acid and acetic acid concentrations of corn-lentil mixed silage were higher(P<0.05).The contents of dry matter,crude protein,crude ash,calcium and crude fat in corn and lentil mixed silage were increased by 1.04%,0.45%,0.87%,0.25%and 0.34%,respectively(P<0.05),while the contents of neutral detergent fiber and acid detergent fiber were 12.78%and 7.57%lower than that of silage corn(P<0.05).Compared with corn silage,the degradation of rumen dry matter,crude protein,neutral detergent fiber and acid detergent fiber of corn-lentil mixed silage was significantly improved(P<0.05).Compared with corn silage,the apparent digestibility of dry matter,crude protein,neutral detergent fiber and acid detergent fiber in corn-lentil silage group increased by 7.67%,7.84%,5.18%and 8.54%,respectively(P<0.05).During the 60 days of the experiment,the average milk yield of cows fed with corn and lentil mixture silage was 3.02 kg/d higher than that of the corn silage group(P<0.05),and milk protein was also significantly increased(P<0.05).To sum up,compared with silage corn,corn-lentil mixed silage improves the fermentation characteristics and nutritional value of silage,and feeding corn-lentil mixed silage to cows can improve nutrient apparent digestibility,milk yield and milk protein of cows.