Mhlongo Lindokuhle C, Kenyon Piers, Nsahlai Ignatius V
Animal and Poultry Science, School of Agricultural, Earth and Environmental Sciences, University of KwaZulu-Natal, Private Bag X01, Pietermaritzburg 3209, South Africa.
Ntlangwini Makhoba Farming (PTY) LTD, Makhoba Land, Swartberg, KwaZulu-Natal, 4170, South Africa.
Vet Anim Sci. 2023 May 29;21:100299. doi: 10.1016/j.vas.2023.100299. eCollection 2023 Sep.
This study investigated the effects of including different types of (tannin extract and forage) on nutrient intake and milk performance in dairy cattle. Holstein-Friesian x Jersey dairy cows ( per Experiment = 24) that had 200 days in milk were selected for this study in a completely randomized study design. This study was conducted under on-farm conditions at Springfontein dairy farm, a farm that lacked a functional bodyweight scale to measure the cow bodyweight and a computer system to register cow parity. Cows were assigned tannin extract (ATE) pellets which were added with 0 (0ATE), 0.75 (0.75ATE), 1.5 (1.5ATE) or 3 (3ATE) % ATE in pellets while 0ATE was a commercial protein concentrate (Experiment 1). Cows were assigned forage (AMF) at a rate of 0 (0AMF), 5 (5AMF), 15 (15AMF) or 25 (25AMF) % AMF inclusion in corn silage-based diet (Experiment 2). For both Experiments, treatments had six cows each, in which they were adapted (14 d) to diets before data collection (21 d). All AMF inclusions decreased (<0.0001) dry matter intake (DMI), crude protein intake (CPI), neutral detergent fibre intake (NDFI), acid detergent fibre intake (ADFI) and organic matter intake (OMI) at 25AMF. Linear (<0.0001) and quadratic (<0.001) effects were observed on DMI, CPI, NDFI, ADFI and OMI. Inclusions of AMF in corn silage diets affected milk yield, protein yield, lactose yield and milk protein percentage (<0.001). Linear effect was present in milk yield per DMI (<0.0001). In conclusion, the dairy cow diet supplemented with ATE pellets did not have a beneficial effect on the nutrient intakes and milk yield. However, the AMF supplemented in corn silage of the dairy cow diet, increased milk production due to positive effects on nutrient intake, which was favourably influenced from a nutritional point of view.
本研究调查了添加不同类型的（单宁提取物和草料）对奶牛营养摄入量和产奶性能的影响。在一项完全随机的研究设计中，选择了产奶200天的荷斯坦 - 弗里生×泽西奶牛（每个实验 = 24头）用于本研究。本研究在斯普林方丹奶牛场的农场条件下进行，该农场缺乏用于测量奶牛体重的功能性体重秤和用于记录奶牛胎次的计算机系统。给奶牛分配添加了0（0ATE）、0.75（0.75ATE）、1.5（1.5ATE）或3（3ATE）% ATE的单宁提取物（ATE）颗粒，而0ATE是一种商业蛋白质浓缩物（实验1）。给奶牛分配以0（0AMF）、5（5AMF）、15（15AMF）或25（25AMF）% AMF比例添加到基于玉米青贮饲料的日粮中的草料（AMF）（实验2）。对于两个实验，每个处理有6头奶牛，在数据收集（21天）之前，它们先适应（14天）日粮。在25AMF时，所有AMF添加量均降低（<0.0001）干物质摄入量（DMI）、粗蛋白摄入量（CPI）、中性洗涤纤维摄入量（NDFI）、酸性洗涤纤维摄入量（ADFI）和有机物摄入量（OMI）。在DMI、CPI、NDFI、ADFI和OMI上观察到线性（<0.0001）和二次（<0.001）效应。在玉米青贮日粮中添加AMF会影响产奶量、蛋白质产量、乳糖产量和乳蛋白百分比（<0.001）。每单位DMI的产奶量存在线性效应（<0.0001）。总之，补充ATE颗粒的奶牛日粮对营养摄入量和产奶量没有有益影响。然而，在奶牛日粮的玉米青贮中补充AMF，由于对营养摄入有积极影响，从而提高了产奶量，从营养角度来看这是有利的影响。
