Hatate Kaoru, Kayano Mitsunori, Kawashima Chiho, Hanada Masaaki, Bicalho Rodrigo C, Yamagishi Norio
Clinical Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
Department of Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, 2-11, Inada, Obihiro, Hokkaido 080-8555, Japan.
J Vet Med Sci. 2019 Jan 8;81(1):15-21. doi: 10.1292/jvms.18-0453. Epub 2018 Nov 7.
The aim of this study was to elucidate the bone metabolic status after taking colostrum in newborn calves. Fourteen neonatal calves were randomly allocated to two groups fed either unheated or heated (60°C, 30 min) colostrum three times on the first day (2 l every 10 hr; 6 l in total). Heat treatment on colostrum was to reduce the bone metabolic markers assumed as heat-sensitive. The concentrations of four bone metabolic markers (the enzymes from bone cells or the bone collagen fragments) and a bone protective protein, osteoprotegerin (OPG), were measured in the blood of calves during a week after the birth and in the colostrum. The colostral concentrations of four bone metabolic markers were reduced by heating. Then those circulatory markers peaked after colostrum intake in the calves fed unheated colostrum; whereas those fed heated colostrum did not show such changes. However, the plasma tartrate resistant acid phosphatase 5b (TRAP5b) activity was transiently increased after taking colostrum in both groups. Meanwhile, heating did not decrease colostral OPG and there was no significant rise in the serum OPG concentrations after the first colostrum intake in both groups. The study revealed that the blood concentrations of studied bone metabolic markers depended on those colostral values except for TRAP5b. Based on the plasma TRAP5b changes, accelerated formation of premature osteoclast cells may be induced by colostrum intake. Meanwhile, colostral OPG absorption is less likely to impact on its circulating levels.
本研究的目的是阐明新生犊牛摄入初乳后的骨代谢状况。14头新生犊牛被随机分为两组，在出生第一天分别喂食未经加热或加热（60°C，30分钟）的初乳，共三次（每10小时2升；总共6升）。对初乳进行热处理是为了降低被认为对热敏感的骨代谢标志物。在出生后一周内，测定犊牛血液和初乳中四种骨代谢标志物（来自骨细胞的酶或骨胶原片段）以及一种骨保护蛋白骨保护素（OPG）的浓度。四种骨代谢标志物的初乳浓度通过加热而降低。然后，在喂食未经加热初乳的犊牛摄入初乳后，这些循环标志物达到峰值；而喂食加热初乳的犊牛则未出现此类变化。然而，两组犊牛摄入初乳后，血浆抗酒石酸酸性磷酸酶5b（TRAP5b）活性均短暂升高。同时，加热并未降低初乳中的OPG，两组犊牛首次摄入初乳后血清OPG浓度均未显著升高。研究表明，除TRAP5b外，所研究的骨代谢标志物的血液浓度取决于初乳中的浓度。基于血浆TRAP5b的变化，摄入初乳可能会诱导破骨前体细胞加速形成。同时，初乳中OPG的吸收不太可能影响其循环水平。
