Rodrigues M C, Cooke R F, Marques R S, Cappellozza B I, Arispe S A, Keisler D H, Bohnert D W
J Anim Sci. 2015 Sep;93(9):4443-52. doi: 10.2527/jas.2015-9277.
The objective of this study was to evaluate intake, metabolic, inflammatory, and acute-phase responses in beef heifers vaccinated against pathogens that cause bovine respiratory disease (BRD). Eighteen weaned Angus heifers (initial BW 257 ± 3 kg; initial age 245 ± 2 d) were ranked by BW and allocated to 2 groups, which were assigned to 2 experiments of 7 d and the following treatments on d 1 of each experiment: 1) revaccinated against infectious bovine rhinotracheitis virus, parainfluenza-3 virus, bovine respiratory syncytial virus, bovine viral diarrhea Types 1 and 2 viruses, and (VAC; 2 mL [s.c.]) and 2) receiving a 2-mL s.c. injection of 0.9% sterile saline (CON). The group receiving VAC in Exp. 1 was assigned to CON in Exp. 2 and vice versa. Heifers were weaned 21 d before Exp. 1, when they all received the first dose of the aforementioned vaccine. Heifers were maintained in individual pens and offered free-choice mixed alfalfa-grass hay and 3.5 kg/d (DM basis) of a corn-based supplement throughout the study. During Exp. 1, hay and concentrate intake were evaluated daily. During Exp. 2, blood samples were collected before (-2 and 0 h) and at 2, 4, 6, 8, 12, 16, 24, 36, 48, 60, 72, 96, 120, 144, and 168 h after treatment administration. In Exp. 1, treatment × day interactions were detected ( < 0.01) for forage intake and total DMI; these parameters were reduced ( ≤ 0.05) in VAC heifers compared with CON heifers on d 1 and 2 by an average of 1.7 and 0.8 kg (DM basis), respectively. In Exp. 2, mean serum tumor necrosis factor α (TNFα) concentration was greater ( = 0.05) in VAC heifers compared with CON heifers and treatment × hour interactions were detected for all plasma variables ( ≤ 0.02), whereas a similar tendency was detected ( = 0.09) for blood α mRNA expression. Haptoglobin concentrations were greater ( ≤ 0.05) in VAC heifers compared with CON heifers from 16 to 120 h. Blood α mRNA expression was greater ( = 0.05) in VAC heifers compared with CON heifers at 12 h. Cortisol concentrations were greater ( ≤ 0.05) in VAC heifers compared with CON heifers from 2 to 16 h. Insulin concentration was greater ( = 0.02) in VAC heifers compared with CON heifers at 2 h. Leptin concentrations were greater ( ≤ 0.05) in VAC heifers compared with CON heifers from 6 to 16 h. In conclusion, vaccinating beef heifers against BRD pathogens decreased forage intake and total DMI during the 2 d following vaccination in Exp. 1, which can be associated with transient metabolic, inflammatory, and acute-phase responses elicited by vaccination in Exp. 2.
本研究的目的是评估接种针对引起牛呼吸道疾病（BRD）的病原体的疫苗后，肉牛小母牛的摄入量、代谢、炎症和急性期反应。将18头断奶的安格斯小母牛（初始体重257±3千克；初始年龄245±2天）按体重排名并分为2组，每组被分配到两个为期7天的实验中，并在每个实验的第1天接受以下处理：1）再次接种传染性牛鼻气管炎病毒、副流感3型病毒、牛呼吸道合胞体病毒、牛病毒性腹泻1型和2型病毒疫苗（VAC；2毫升[皮下注射]），2）皮下注射2毫升0.9%无菌生理盐水（CON）。实验1中接受VAC处理的组在实验2中被分配到CON组，反之亦然。小母牛在实验1前21天断奶，那时它们都接受了上述疫苗的第一剂。在整个研究过程中，小母牛被饲养在单独的围栏中，并可自由选择苜蓿-禾本科混合干草和每天3.5千克（干物质基础）的玉米基补充料。在实验1期间，每天评估干草和精料摄入量。在实验2期间，在处理给药前（-2和0小时）以及给药后2、4、6、8、12、16、24、36、48、60、72、96、120、144和168小时采集血样。在实验1中，检测到处理×天数交互作用（P<0.01）对采食量和总干物质摄入量有影响；与CON组小母牛相比，VAC组小母牛在第1天和第2天的这些参数分别平均降低了1.7千克和0.8千克（干物质基础）（P≤0.05）。在实验2中，与CON组小母牛相比，VAC组小母牛的平均血清肿瘤坏死因子α（TNFα）浓度更高（P = 0.05），并且检测到所有血浆变量的处理×小时交互作用（P≤0.02），而血液α mRNA表达也有类似趋势（P = 0.09）。与CON组小母牛相比，VAC组小母牛在第16至120小时的触珠蛋白浓度更高（P≤0.05）。与CON组小母牛相比，VAC组小母牛在第12小时的血液α mRNA表达更高（P = 0.05）。与CON组小母牛相比，VAC组小母牛在第2至16小时的皮质醇浓度更高（P≤0.05）。与CON组小母牛相比，VAC组小母牛在第2小时的胰岛素浓度更高（P = 0.02）。与CON组小母牛相比，VAC组小母牛在第6至16小时的瘦素浓度更高（P≤0.05）。总之，在实验1中，给肉牛小母牛接种BRD病原体疫苗后，在接种后的2天内采食量和总干物质摄入量减少，这可能与实验2中接种疫苗引发的短暂代谢、炎症和急性期反应有关。
