Staley G P, van der Lugt J J, Axsel G, Loock A H
Department of Theriogenology, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Republic of South Africa.
J S Afr Vet Assoc. 1994 Jun;65(2):73-8.
Holstein calves (n = 47) with a dwarf-like appearance, joint laxity, superior brachygnathism and domed foreheads were born to heifers on natural grazing on the same farm. Six calves, between one week and 3 months of age, were euthanased. Marginally low concentrations of manganese were found in the livers, while high strontium concentrations were confirmed in soil, plants and grass specimens from the pasture, as well as in the bone ash of the ribs of 2 calves. Microscopical lesions in growth plates included irregularly aligned and shorter columns of chondrocytes and a reduction in width of the zone of hypertrophy when compared to a normal calf. This syndrome closely resembled a previously described chondrodystrophy in neonatal calves, attributed to a maternal manganese deficiency. Seepage from sea water evaporation pans on an adjacent farm was believed to have resulted in leaching of manganese from the soil and to be the source of the high levels of strontium. The cause of the skeletal defects is believed to be maternal manganese deficiency, complicated by an unknown factor.
在同一农场自然放牧的小母牛产下了47头荷斯坦犊牛,这些犊牛外观似侏儒,关节松弛,上颌前突,额头隆起。对6头1周龄至3月龄的犊牛实施了安乐死。在犊牛肝脏中发现锰含量略低,而在牧场的土壤、植物和草样本以及2头犊牛肋骨的骨灰中证实锶含量很高。与正常犊牛相比,生长板的显微镜下病变包括软骨细胞柱排列不规则且变短,以及肥大区宽度减小。这种综合征与先前描述的新生犊牛软骨发育不良非常相似,归因于母体锰缺乏。据信,相邻农场海水蒸发池的渗漏导致土壤中的锰被淋溶,是锶含量高的来源。骨骼缺陷的原因被认为是母体锰缺乏,并伴有一个未知因素。