Department of Animal Breeding and Nutrition, São Paulo State University (FMVZ-UNESP), Botucatu, São Paulo, Brazil.
J Anim Sci. 2011 Oct;89(10):3228-35. doi: 10.2527/jas.2010-3062. Epub 2011 May 6.
Nine ruminally cannulated cows fed different energy sources were used to evaluate an avian-derived polyclonal antibody preparation (PAP-MV) against the specific ruminal bacteria Streptococcus bovis, Fusobacterium necrophorum, Clostridium aminophilum, Peptostreptococcus anaerobius, and Clostridium sticklandii and monensin (MON) on ruminal fermentation patterns and in vivo digestibility. The experimental design was three 3 × 3 Latin squares distinguished by the main energy source in the diet [dry-ground corn grain (CG), high-moisture corn silage (HMCS), or citrus pulp (CiPu)]. Inside each Latin square, animals received one of the feed additives per period [none (CON), MON, or PAP-MV]. Dry matter intake and ruminal fermentation variables such as pH, total short-chain fatty acids (tSCFA), which included acetate, propionate, and butyrate, as well as lactic acid and NH(3)-N concentration were analyzed in this trial. Total tract DM apparent digestibility and its fractions were estimated using chromic oxide as an external marker. Each experimental period lasted 21 d. Ruminal fluid sampling was carried out on the last day of the period at 0, 2, 4, 6, 8, 10, and 12 h after the morning meal. Ruminal pH was higher (P = 0.006) 4 h postfeeding in MON and PAP-MV groups when compared with CON. Acetate:propionate ratio was greater in PAP-MV compared with MON across sampling times. Polyclonal antibodies did not alter (P > 0.05) tSCFA, molar proportion of acetate and butyrate, or lactic acid and NH(3)-N concentration. Ruminal pH was higher (P = 0.01), 4 h postfeeding in CiPu diets compared with CG and HMCS. There was no interaction between feed additive and energy source (P > 0.05) for any of the digestibility coefficients analyzed. Starch digestibility was less (P = 0.008) in PAP-MV when compared with CON and MON. In relation to energy sources, NDF digestibility was greater (P = 0.007) in CG and CiPu vs. the HMCS diet. The digestibility of ADF was greater (P = 0.002) in CiPu diets followed by CG and HMCS. Feeding PAP-MV or monensin altered ruminal fermentation patterns and digestive function in cows; however, those changes were independent of the main energy source of the diet.
本试验选用 9 头安装有永久性瘤胃瘘管的奶牛，研究了一种针对特定瘤胃细菌（牛链球菌、坏死梭杆菌、产氨瘤胃球菌、厌氧消化链球菌和丁酸梭菌）的禽源多克隆抗体制剂（PAP-MV）和莫能菌素（MON）对瘤胃发酵模式和体内消化率的影响，这些奶牛分别饲喂不同能量来源的日粮。试验采用 3×3 拉丁方设计，日粮的主要能量来源分别为：干粉碎玉米（CG）、高水分青贮玉米（HMCS）和柑橘渣（CiPu）。每个拉丁方内，动物在每个试验期内接受一种饲料添加剂：无添加（CON）、MON 或 PAP-MV。试验分析了干物质采食量和瘤胃发酵变量，如 pH 值、总短链脂肪酸（tSCFA）、乙酸、丙酸和丁酸以及乳酸和 NH3-N 浓度。采用外源指示剂三氧化二铬（Cr2O3）估算了全肠道 DM 表观消化率及其各组分。每个试验期持续 21d。在每个试验期的最后 1d，在采食后 0、2、4、6、8、10 和 12h 进行瘤胃液采样。与 CON 组相比，MON 和 PAP-MV 组在采食后 4h 的瘤胃 pH 值更高（P = 0.006）。与 MON 组相比，PAP-MV 组在整个采样时间内的乙酸：丙酸比例更高。多克隆抗体未改变（P > 0.05）tSCFA、乙酸和丁酸的摩尔比例或乳酸和 NH3-N 浓度。与 CG 和 HMCS 日粮相比，CiPu 日粮在采食后 4h 的瘤胃 pH 值更高（P = 0.01）。对于分析的任何消化率系数，饲料添加剂和能量来源之间均无互作效应（P > 0.05）。与 CON 和 MON 相比，PAP-MV 组的淀粉消化率更低（P = 0.008）。与 HMCS 日粮相比，CG 和 CiPu 日粮的 NDF 消化率更高（P = 0.007）。在 ADF 消化率方面，CiPu 日粮最高，其次是 CG 和 HMCS 日粮（P = 0.002）。给奶牛饲喂 PAP-MV 或 MON 会改变瘤胃发酵模式和消化功能；然而，这些变化与日粮的主要能量来源无关。
