Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853.
Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853.
J Dairy Sci. 2017 Dec;100(12):9681-9690. doi: 10.3168/jds.2017-12885. Epub 2017 Oct 4.
Our objectives were to measure serum Ca concentrations in the first 48 h postpartum in cows supplemented with oral Ca or subcutaneous Ca and nonsupplemented cows and evaluate the effect of these treatments on the incidence of metritis, displaced abomasum, mastitis, and early lactation disease (any of the diseases milk fever, retained placenta, metritis, or displaced abomasum), removal from the herd, pregnancy to first insemination, and average daily milk yield for the first 10 wk of lactation. We conducted 2 experiments on 1 commercial herd in New York State. In experiment 1, multiparous Holstein cows (n = 30) were blocked by parity (2 and ≥3) and sequentially assigned at calving to nontreated control (CON, n = 10), subcutaneous administration of 500 mL 23% Ca gluconate at calving (SC, n = 10), or administration of an oral Ca bolus containing 43 g of calcium at calving and again 12 h later (OB, n = 10). Blood was collected before treatment and at 1, 2, 4, 8, 12, 24, and 48 h thereafter for measurement of serum total Ca concentration. In experiment 2, 1,478 multiparous Holstein cows were sequentially assigned by calving date to the same 3 treatments (CON, n = 523; SC, n = 480; OB, n = 475). In experiment 1, SC cows had greater Ca concentrations from 1 through 12 h post-treatment and OB cows had greater Ca concentrations at 1 and 24 h post-treatment compared with CON cows. We found no difference in risk of metritis, displaced abomasum, early lactation disease diagnosis, or pregnancy to first insemination among treatments. Treatment with SC or OB had no effect on average daily milk yield compared with CON cows (CON = 46.7 kg; SC = 47.1 kg; OB = 47.0 kg). Cows treated with SC or OB that had a high relative herd milk rank in the previous lactation were almost half as likely to be diagnosed with mastitis in the first 60 DIM compared with CON cows [risk ratio (RR) = 0.57, RR = 0.54]; however, we found no difference in risk of mastitis among treatments for cows with low relative herd milk rank. Second-parity cows fed a negative prepartum dietary cation-anion difference ration and treated with SC or OB were more likely to be removed from the herd than CON cows (RR = 3.91, RR = 4.72); this difference was not observed in second-parity cows fed a neutral prepartum dietary cation-anion difference ration or in parity ≥3 cows. Although Ca supplementation increased serum Ca, this effect did not greatly improve milk production or health and reproductive outcomes.
我们的目标是测量产后 48 小时内接受口服或皮下补钙的奶牛以及未补钙奶牛的血清 Ca 浓度，并评估这些治疗方法对子宫炎、皱胃移位、乳腺炎和早期泌乳疾病（产褥热、胎衣不下、子宫炎或皱胃移位）、淘汰率、首次配种妊娠率以及泌乳前 10 周的平均日产量的影响。我们在纽约州的一个商业牛群中进行了两项实验。在实验 1 中，将产次为 2 次和≥3 次的荷斯坦奶牛（n=30）按产次（2 次和≥3 次）分为 2 组，然后在分娩时依次分为未治疗对照组（CON，n=10）、分娩时皮下注射 500 毫升 23%葡萄糖酸钙（SC，n=10）或分娩时口服含有 43 克钙的钙丸，12 小时后再口服一次（OB，n=10）。在治疗前和治疗后 1、2、4、8、12、24 和 48 小时采集血液，以测量血清总 Ca 浓度。在实验 2 中，1478 头产次为 2 次和≥3 次的荷斯坦奶牛，按分娩日期依次分为相同的 3 种治疗组（CON，n=523；SC，n=480；OB，n=475）。在实验 1 中，与 CON 组相比，SC 组奶牛在治疗后 1 至 12 小时的 Ca 浓度更高，而 OB 组奶牛在治疗后 1 小时和 24 小时的 Ca 浓度更高。我们发现治疗方法之间在子宫炎、皱胃移位、早期泌乳疾病诊断或首次配种妊娠的风险方面没有差异。与 CON 组奶牛相比，SC 或 OB 治疗对平均日产量没有影响（CON=46.7kg；SC=47.1kg；OB=47.0kg）。在之前的泌乳期具有较高相对 herd milk rank 的 SC 或 OB 治疗奶牛，在最初的 60 天内患乳腺炎的风险比 CON 组奶牛低一半[风险比（RR）=0.57，RR=0.54]；然而，对于 herd milk rank 较低的治疗奶牛，我们没有发现治疗方法之间在乳腺炎风险方面的差异。与 CON 组奶牛相比，接受负产前阳离子-阴离子差日粮的第二产次奶牛和接受 SC 或 OB 治疗的奶牛更有可能被淘汰（RR=3.91，RR=4.72）；这种差异在接受中性产前阳离子-阴离子差日粮的第二产次奶牛或产次≥3 的奶牛中没有观察到。虽然补钙增加了血清 Ca，但这并没有显著改善产奶量或健康和繁殖结果。
