Manosalva Daniel Gustavo, Grispoldi Luca, Spagnolo Marco, Crociati Martina
Società Agricola Nonno Ciro, Località Foreste Vecchie, 61020 Montecalvo in Foglia, Italy.
Dipartimento di Medicina Veterinaria, Università degli Studi di Perugia, 06126 Perugia, Italy.
Animals (Basel). 2022 Jun 28;12(13):1665. doi: 10.3390/ani12131665.
Timely administration of good-quality colostrum represents the first farm strategy to avoid the failure of passive transfer (FPT). However, calves born during the night are likely to be fed later than recommended. Our aim was to evaluate whether night-occurring calving and delayed first milking affected colostrum quality and immune passive transfer. The dataset included 463 calvings. Four liters of colostrum were administered by an esophageal tube feeder. The mean Brix% of colostrum was 27.43%, while serum Brix% at two days of life in calves was 10.19%. According to the Generalized Linear Model, parity ≥ 4, calving months of March, April, and from September to November positively influenced the quality of colostrum. Dams carrying a male calf produced lower quality colostrum compared with those carrying a female calf (−2.78 ± 1.04 Brix%, p = 0.008); heavier female calves were associated with greater colostrum quality (0.29 ± 0.05 for each kg increase, p < 0.001). Night- or day-calving had no effect on the quality of colostrum. The only factor influencing the serum Brix% of female Holstein calves at two days of life was the day- or night-occurring birth (−0.386 ± 0.188 Brix% in calves born during the night, p = 0.04). Our results showed that calves born overnight and fed the day after had decreased serum Total Protein concentrations as indicated by reduced Brix refractometer readings, compared with calves born during the day and fed quickly after birth. However, the administration of 4 L of high-quality colostrum likely improved their serum Brix% at two days of life. Alternatively, where the prevalence of good-quality colostrum is lower, improving calving supervision and ensuring timely feeding are important to reduce the risk of FPT.
及时投喂优质初乳是避免被动转运失败（FPT）的首要养殖策略。然而，夜间出生的犊牛可能比建议时间更晚才吃到初乳。我们的目的是评估夜间产犊和首次挤奶延迟是否会影响初乳质量和免疫被动转运。数据集包含463次产犊情况。通过食管饲管投喂4升初乳。初乳的平均白利糖度百分比为27.43%，而犊牛出生两天后的血清白利糖度百分比为10.19%。根据广义线性模型，胎次≥4、3月、4月以及9月至11月产犊对初乳质量有正向影响。与怀母犊的母牛相比，怀公犊的母牛所产初乳质量较低（白利糖度百分比降低2.78±1.04，p = 0.008）；较重的母犊与更高的初乳质量相关（每增加1千克白利糖度百分比增加0.29±0.05，p < 0.001）。夜间或白天产犊对初乳质量没有影响。影响荷斯坦母犊出生两天后血清白利糖度百分比的唯一因素是出生在白天还是夜间（夜间出生的犊牛血清白利糖度百分比降低0.386±0.188，p = 0.04）。我们的结果表明，与白天出生并在出生后迅速投喂初乳的犊牛相比，夜间出生并在第二天投喂初乳的犊牛，其血清总蛋白浓度降低，这通过白利糖度折射计读数降低得以体现。然而，投喂4升优质初乳可能会提高它们出生两天后的血清白利糖度百分比。另外，在优质初乳比例较低的情况下，加强产犊监管并确保及时投喂对于降低被动转运失败的风险很重要。
