Studies on abnormalities of hormone and metabolism in Japanese black cattle with growth retardation

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Growth retardation has been observed frequently in Japanese black cattle. The incidence of growth retardation was 3 to 5 % of calves. We investigate pathophysiology of the growth retardation, and try to develop the method of early diagnosis. In cattle with growth retardation, blood thyroid hormone concentrations were lower than normal cattle. However, this was the euthyroid sick syndrome, so that the hypothyroidism was secondary from other abnormalities. Using gas chromatography/mass spectrometry, we analyzed urinary metabolic profiles in cattle with growth retardation. The gas/mass analysis detected a calf with orotic acid uria, but the abnormality of the gene of responsible enzyme, uridine monophosphate synthase, could not be found. Cattle with growth retardation had a characteristic profile among strains, but the abnormality of particular molecule could not be detected. On hormones, growth hormone secretion was more, and plasma insulin-like growth factor (IGF)-1 concentration was lo … More wer in cattle with growth retardation than normal cattle. Moreover, the degree of endocrine secretion abnormality was different by cattle of strain, the cattle in the M strain had higher GH secretion, lower concentrations of IGF-1, T3. T4 and cortisol in plasma than cattle in the H strain. Of cattle with growth retardation, we found many cattle with blood coagulation factor XI deficiency, and the abnormal gene already became diffused in the area. On the other hand, we carried out propionate and arginine tolerance tests and a metabolic profile test, and results indicated the cattle wit growth retardation were at the condition to release energy easily, namely, the condition to be thin down, not to be fat. Cattle with growth retardation had low plasma IGF-1 concentrations constantly, and the longitudinal determination of plasma IGF-1 concentration can be used as an index of growth retardation. In addition, we could make case reports on rare diseases in cattle, thymic atrophy, diabetes mellitus, low body temperature, eosinophilic myositis, pericardial mesothelioma, and cerebellar deficiency. Less