Silva Gleise M, Schulmeister Tessa M, Podversich Federico, Tarnonsky Federico, Garcia-Ascolani Mariana E, DiLorenzo Nicolas
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5, Canada.
North Florida Research and Education Center, University of Florida, Marianna, FL 32446, USA.
Transl Anim Sci. 2022 Jan 27;6(1):txac016. doi: 10.1093/tas/txac016. eCollection 2022 Jan.
This study evaluated the effects of feeding an avian-derived polyclonal antibody preparation (; CAMAS, Inc.) against , , and lipopolysaccharides (; 40%, 35%, and 25% of the preparation, respectively) on growth performance (Exp. 1) and apparent total tract digestibility of nutrients (Exp. 2) of beef cattle consuming a backgrounding diet. In Exp. 1, Angus crossbred heifers ( = 70; 360 ± 24 kg of initial body weight; ) and steers ( = 20; 386 ± 24 kg of BW) were used in a generalized randomized block design. Heifers and steers were allocated to 1 of 18 concrete-surfaced pens (6 pens per treatment) to receive a common ad libitum diet (35% cottonseed hulls, 34% dry-rolled corn, and 20% corn gluten pellets; 15.9% crude protein on a dry matter [] basis, 1.58 Mcal/kg DM of net energy [] of maintenance, and 0.98 Mcal/kg DM of NE of gain) and 1 of the 3 treatments consisting of feeding 1 (), 3 (), or 0 g () of PAP per day for 56 d. Feed intake was recorded daily and BW was obtained on days -1, 0, 14, 28, 42, 55, and 56 to assess average daily gain (), dry matter intake (), and gain:feed (). Plasma concentrations of glucose and haptoglobin were measured on days 0, 14, 28, 42, and 56. In Exp. 2, 25 Angus crossbreed steers (390 ± 24 kg BW) were used in a completely randomized design to receive the same diet and treatments from Exp. 1 (CON: = 8; PAP1: = 9; and PAP3: = 8). Following a 14-d adaptation to diets, feed and fecal samples were collected to determine apparent total tract nutrient digestibility. In Exp. 1, overall BW, DMI, ADG, G:F, and plasmatic measurements did not differ among treatments over the 56-d period ( 0.16). However, from days 0 to 14, a quadratic effect was observed for ADG, in which cattle receiving PAP1 had greater ( = 0.04) ADG compared with CON. In Exp. 2, no difference in DMI was observed ( = 0.88), yet DM, organic matter, neutral and acid detergent fiber, and starch digestibility were least ( ≤ 0.05) for PAP3, whereas digestibility of neutral detergent fiber was greatest ( < 0.01) for PAP1. In summary, feeding 1 g/d of a PAP against , , and LPS improved growth performance in the first 14 d and increased fiber digestibility of beef cattle consuming a backgrounding diet. Further research is needed to understand the impaired responses on nutrient digestibility when greater doses are provided.
本研究评估了饲喂一种抗大肠杆菌、沙门氏菌和脂多糖的禽源多克隆抗体制剂（Camas公司）（分别占制剂的40%、35%和25%）对采食育成期日粮的肉牛生长性能（试验1）和养分表观全肠道消化率（试验2）的影响。在试验1中，安格斯杂交小母牛（n = 70；初始体重360±24千克）和阉牛（n = 20；体重386±24千克）采用广义随机区组设计。小母牛和阉牛被分配到18个水泥地面栏舍中的1个（每个处理6个栏舍），自由采食相同日粮（35%棉籽壳、34%干压玉米和20%玉米蛋白粉；干物质基础上粗蛋白含量15.9%，维持净能1.58兆卡/千克干物质，增重净能0.98兆卡/千克干物质），并接受3种处理中的1种，即每天饲喂1克（PAP1）、3克（PAP3）或0克（对照）多克隆抗体制剂，持续56天。每天记录采食量，并在第-1、0、14、28、42、55和56天测量体重，以评估平均日增重（ADG）、干物质采食量（DMI）和增重：采食量（G:F）。在第0、14、28、42和56天测量血浆葡萄糖和触珠蛋白浓度。在试验2中，25头安格斯杂交阉牛（体重390±24千克）采用完全随机设计，采食与试验1相同的日粮和处理（对照：n = 8；PAP1：n = 9；PAP3：n = 8）。在适应日粮14天后，采集饲料和粪便样本以测定养分表观全肠道消化率。在试验1中，在56天的试验期内，各处理间的总体体重、DMI、ADG、G:F和血浆指标均无差异（P＞0.16）。然而，在第0至14天，ADG观察到二次效应，接受PAP1的牛的ADG高于对照（P = 0.04）。在试验2中，DMI无差异（P = 0.88），但PAP3组的干物质、有机物、中性和酸性洗涤纤维以及淀粉消化率最低（P≤0.05），而PAP1组的中性洗涤纤维消化率最高（P＜0.01）。总之，每天饲喂1克抗大肠杆菌、沙门氏菌和脂多糖的多克隆抗体制剂可在最初14天提高生长性能，并提高采食育成期日粮的肉牛的纤维消化率。需要进一步研究以了解提供更高剂量时养分消化率受损的反应。
