Pearson Jennifer M, Pajor Edward, Campbell John, Levy Michel, Caulkett Nigel, Windeyer M Claire
Production Animal Health, University of Calgary Faculty of Veterinary Medicine, Calgary, Alberta, Canada.
Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Vet Rec Open. 2019 Oct 19;6(1):e000364. doi: 10.1136/vetreco-2019-000364. eCollection 2019.
The objectives of this study were to investigate the impact of pain mitigation at birth to assisted beef calves and determine the risk factors associated with transfer of passive immunity (TPI), health, and growth.
Two hundred and thirty cow-calf pairs requiring calving assistance were enrolled. Calves were randomised to receive meloxicam (0.5 mg/kg) or an equivalent volume of placebo subcutaneously at birth. Calf blood samples were collected between one and seven days of age to determine serum immunoglobulin (IgG) concentration. Colostrum intake, treatment for disease, mortality, and weaning weights were recorded. Multilevel linear or logistic regression models were used to determine the effects of meloxicam and to identify risk factors.
There was no effect of meloxicam on serum IgG concentrations, average daily gain (ADG), or risk of inadequate TPI (serum IgG concentration <24 g/l), treatment for disease, or mortality (P>0.05). Bottle or tube feeding calves were associated with decreased serum IgG concentrations (P=0.01) compared with nursing. Calves with an incomplete tongue withdrawal reflex had higher odds of being treated for disease compared with those with complete withdrawal (P=0.009). Being born meconium-stained and having decreased serum IgG concentrations were associated with an increased risk of mortality (P=0.03). Being born of a mature cow, having a higher birth weight, and increased serum IgG concentrations were associated with greater ADG to weaning (P<0.05).
Vigour assessment at birth along with good colostrum management may be important to improve TPI and health in high-risk calves such as those assisted at birth.
本研究的目的是调查减轻出生时疼痛对肉牛犊的影响,并确定与被动免疫转移(TPI)、健康和生长相关的风险因素。
招募了230对需要助产的母牛-牛犊对。犊牛在出生时被随机分为皮下注射美洛昔康(0.5mg/kg)或等量安慰剂组。在犊牛出生后1至7天采集血样,以测定血清免疫球蛋白(IgG)浓度。记录初乳摄入量、疾病治疗情况、死亡率和断奶体重。使用多水平线性或逻辑回归模型来确定美洛昔康的效果并识别风险因素。
美洛昔康对血清IgG浓度、平均日增重(ADG)、TPI不足风险(血清IgG浓度<24g/l)、疾病治疗或死亡率均无影响(P>0.05)。与哺乳相比,用奶瓶或管子喂养的犊牛血清IgG浓度降低(P=0.01)。与舌退缩反射完全的犊牛相比,舌退缩反射不完全的犊牛疾病治疗几率更高(P=0.009)。出生时胎粪污染和血清IgG浓度降低与死亡率增加相关(P=0.03)。出生于成年母牛、出生体重较高以及血清IgG浓度增加与断奶前更大的ADG相关(P<0.05)。
出生时的活力评估以及良好的初乳管理对于改善高危犊牛(如出生时接受助产的犊牛)的TPI和健康可能很重要。