Department of Animal Science, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran.
Animal Science Research Department, Isfahan Agriculture and Natural resources Research and Education Center, Agriculture Research, Education and Extension Organization (AREEO), Isfahan, Iran.
Vet Med Sci. 2023 Sep;9(5):2230-2237. doi: 10.1002/vms3.1203. Epub 2023 Jul 17.
Total serum protein (TSP) within the first few days of life in the neonatal calf has predictive value for subsequent growth and production in calves before and after weaning.
The objective of this study was to evaluate the effect of TSP concentration 24-h after birth (24-h) on the performance and health of Holstein dairy calves.
A total of 152 female calves were enrolled in this study. Blood samples were collected at 24-h, and TSP concentration was measured with a refractometer. Calves based on TSP concentration at 24-h were allocated into three groups: 1 - TSP ≤6.5 g/dL, 2 - TSP between 6.6 and 6.9 g/dL and 3 - TSP ≥7 g/dL. The weighing was done at birth and at days 30 and 60. Starter feed intake was recorded from day 3 to weaning, and body structures were measured at birth and weaning day.
Calves with TSP >6.5 g/dL had greater body weight at days 30 and 60 than calves with TSP ≤6.5 g/dL. Average daily gain during 1-30 and 1-60 days of life increased as TSP increased. Furthermore, starter feed intake during the first 60 days of life was greater in calves with TSP ≥7 g/dL than calves with TSP <7 g/dL. The TSP concentration influenced structural growth, and >6.5 g/dL calves had greater heart girth, hip width and body length than ≤6.5 g/dL calves. Moreover, odds ratio for pneumonia decreased as TSP increased, whereas diarrhoea was unaffected.
The TSP at 24-h is an important contributing factor for the variation in growth performance and health of preweaning calves, and strategies to improve calf immunity and increase TSP lead to better animal health during preweaning period.
These results indicated that TSP ≥6.5 g/dL possibly was associated with greater performance, and this concentration could be considered a baseline for future analyses.
新生犊牛出生后最初几天内的总血清蛋白（TSP）对犊牛断奶前后的后续生长和生产具有预测价值。
本研究的目的是评估出生后 24 小时（24 小时）TSP 浓度对荷斯坦奶牛犊牛生长性能和健康的影响。
本研究共纳入 152 头雌性犊牛。在 24 小时时采集血样，并使用折射计测量 TSP 浓度。根据 24 小时 TSP 浓度，犊牛被分为三组：1 - TSP ≤6.5g/dL、2 - TSP 6.6-6.9g/dL 和 3 - TSP ≥7g/dL。在出生时和 30 天和 60 天时进行称重。从第 3 天到断奶时记录开始饲料摄入量，并在出生和断奶日测量身体结构。
TSP >6.5g/dL 的犊牛在 30 天和 60 天的体重大于 TSP ≤6.5g/dL 的犊牛。1-30 天和 1-60 天的平均日增重随着 TSP 的增加而增加。此外，在生命的头 60 天，TSP ≥7g/dL 的犊牛的起始饲料摄入量大于 TSP <7g/dL 的犊牛。TSP 浓度影响结构生长，TSP >6.5g/dL 的犊牛的胸围、臀宽和体长大于 TSP ≤6.5g/dL 的犊牛。此外，随着 TSP 的增加，肺炎的比值比降低，而腹泻不受影响。
24 小时 TSP 是影响断奶前犊牛生长性能和健康变化的重要因素，提高犊牛免疫力和增加 TSP 的策略可改善断奶前的动物健康。
这些结果表明，TSP ≥6.5g/dL 可能与更高的性能相关，该浓度可作为未来分析的基线。
