Consumption of an adequate volume of high-quality colostrum is vital to a dairy calf's ability to survive and become a productive herd member. However, some dairy herds have reported a deficiency of colostrum production, which ranges from a low volume to no colostrum produced, by cows during fall and winter. Little information regarding this phenomenon exists. The purpose of this study was to characterize the syndrome and identify potential risk factors for low colostrum yield. A 2,500-cow Jersey dairy farm was enrolled in a prospective cohort study in May 2016, to evaluate possible effects of photoperiod, temperature, and cow factors on colostrum production. Dairy personnel were trained to collect, weigh, and evaluate colostrum quality. Information on parity, previous lactation length, previous 305-d mature equivalent milk production, and dry period length were collected through the farm's dairy management software. Weather and photoperiod data were also collected. Over the year of enrollment, 2,988 eligible cows calved and had colostrum weights recorded and 38% were primiparous (n = 1,143), 25% were in their second lactation (n = 752), and 37% were in their third or greater lactation (n = 1,093). The overall average colostrum yield was 6.6 kg/cow in June 2016, 2.5 kg/cow in December 2016, and 4.8 kg/cow in May 2017. Multiparous cows had a larger decline in colostrum production between June and December (6.6 to 1.3 kg/cow) compared with primiparous animals (6.5 to 4.2 kg/cow). Overall, average colostrum production decreased by 0.17 kg/cow per week during this time, 0.22 kg for multiparous cows and 0.08 kg for primiparous cows. A logistic regression model was constructed for all cows to evaluate effects of cow factors on low colostrum production (<2.7 kg at first milking). Dry period length, calf sex, singleton or twin, age at freshening, month of calving and previous lactation length were significantly associated with the probability of low colostrum yield (<2.7 kg at first milking). A cross-correlation function analysis between the time series for colostrum yield and photoperiod revealed a high correlation at the time of calving and 1 mo prior, particularly for multiparous cows. A pedigree analysis showed that extreme colostrum yield (low vs. high) followed some sire lines. Low colostrum production in this herd could have an economic effect on the dairy and calf health and appears to have a strong seasonal and, potentially, a genetic component.

摄入足够数量的优质初乳对于奶牛的生存能力和成为成群的牛群至关重要。但是，据报告，一些奶牛牛在秋冬季节的初乳生产不足，从低产量到无初乳的范围不等。关于此现象的信息很少。这项研究的目的是表征综合征并确定初乳产量低的潜在危险因素。2016年5月，一个2500牛的泽西岛奶牛场参加了一项前瞻性队列研究，以评估光周期，温度和奶牛因素对初乳生产的可能影响。乳制品人员接受了收集，称重和评估初乳质量的培训。有关平价，先前哺乳期，先前305天成熟当量奶产量的信息，通过农场的乳品管理软件收集干燥期和干燥期的长度。还收集了天气和光周期数据。在入学的那一年，有2988头符合条件的母牛被犊牛并记录了初乳重量，其中38％为初产（n = 1143），25％在其第二次泌乳（n = 752），37％在其第三次或更多次泌乳（ n = 1,093）。2016年6月的整体平均初乳产量为6.6公斤/头，2016年12月为2.5公斤/头，2017年5月为4.8公斤/头。6月至12月间，多头母牛的初乳产量下降幅度更大（6.6至1.3公斤/头）。牛）与初生动物（6.5至4.2千克/牛）相比。总体而言，在此期间，每周平均初乳产量降低了0.17千克/母牛，多头母牛为0.22千克，初产母牛为0.08千克。为所有奶牛建立了逻辑回归模型，以评估奶牛因素对低初乳产量（第一次挤奶时<2.7 kg）的影响。干燥期的长度，犊牛的性别，单胎或双胎，新鲜的年龄，产犊的月份和以前的泌乳期与初乳产量低的可能性（第一次挤奶时<2.7 kg）显着相关。初乳产量和光周期的时间序列之间的互相关函数分析显示，产犊时和事发前1个月有高度相关性，特别是对于多头母牛。家谱分析表明，初乳产量极高（低与高）遵循一些父系。牛群中初乳产量低可能对奶牛和小牛的健康产生经济影响，并且似乎具有很强的季节性和潜在的遗传成分。