Sharma Bharti, Nimje Prapti, Tomar S K, Dey Dipak, Mondal Santu, Kundu S S
Indian Council of Agricultural Research (ICAR), National Dairy Research Institute (NDRI), Animal Nutrition Division, Karnal -132001 (Haryana), India.
Indian Council of Agricultural Research (ICAR), National Dairy Research Institute (NDRI), Livestock Production and Management, Karnal -132001 (Haryana), India.
Asian-Australas J Anim Sci. 2020 Jan 1;33(1):53-60. doi: 10.5713/ajas.18.0604. Epub 2019 Feb 7.
The current study was carried out to examine the response of different levels of fat and protein in calf starter on nutrient utilisation, nitrogen metabolism, weight gain, blood parameters and immunity level in pre-ruminant calves.
Twenty four calves (5 days old) were divided into six groups in a 2x3 factorial design, with two levels of fat (10% and 14 %) and three levels of protein (18%, 21% and 24%). The calves were kept in individual pens for 120 days and fed with whole milk (1/10th of body weight) and calf starter ad-libitum. Daily dry matter intake (DMI) was recorded; whereas body weight was taken on fortnightly basis to calculate average daily gain (ADG). During the growth trial blood samples were collected at 30 days interval to estimate blood glucose, albumin, total protein, total leucocyte count, total immunoglobulin and IgG levels. A metabolic trial of seven days was carried out to find out the digestibility of different nutrients.
The DMI was reduced (p<0.05) with higher fat and protein levels whereas feed conversion efficiency (FCE) was improved (p<0.05) with higher protein level. Different levels of fat and protein in calf ration did not affect average daily gain in calves.The dry matter (DM), organic matter (OM) and crude protein (CP) digestibility were significantly (p<0.01) higher with increased level of protein. The nitrogen retention was also significantly higher (p<0.05) at 24 % protein level, similarly the total immunoglobulin was significantly (p< 0.05) high in higher protein fed groups, showed better immunity.
The present finding suggested that 10 % fat and 18 % protein level of calf starter could be used in Sahiwal calves for optimum performance in terms of weight gain and immunity.
本研究旨在探讨犊牛开食料中不同水平的脂肪和蛋白质对反刍前犊牛营养物质利用、氮代谢、体重增加、血液参数和免疫水平的影响。
将24头（5日龄）犊牛按2×3析因设计分为六组，设有两个脂肪水平（10%和14%）和三个蛋白质水平（18%、21%和24%）。将犊牛单独饲养在栏舍中120天，自由采食全脂牛奶（体重的1/10）和犊牛开食料。记录每日干物质摄入量（DMI）；每两周测量一次体重以计算平均日增重（ADG）。在生长试验期间，每隔30天采集血液样本，以测定血糖、白蛋白、总蛋白、白细胞总数、总免疫球蛋白和IgG水平。进行为期七天的代谢试验以测定不同营养物质的消化率。
较高的脂肪和蛋白质水平使DMI降低（p<0.05），而较高的蛋白质水平提高了饲料转化效率（FCE）（p<0.05）。犊牛日粮中不同水平的脂肪和蛋白质对犊牛的平均日增重没有影响。随着蛋白质水平的提高，干物质（DM）、有机物（OM）和粗蛋白（CP）的消化率显著提高（p<0.01）。蛋白质水平为24%时，氮保留也显著更高（p<0.05），同样，高蛋白饲喂组的总免疫球蛋白显著更高（p<0.05），表明免疫力更强。
目前的研究结果表明，对于萨希瓦尔犊牛，犊牛开食料中10%的脂肪和18%的蛋白质水平可使其在体重增加和免疫方面达到最佳性能。
