The causes of mortality in kids under extensive conditions in the Mexico plateau were studied. Perinatal mortality of kids (0-7 days) was lower (P<0.05) than mortality in the other age groups (8-90 days). The weights of the animals at death were extremely low, group (i) 0-7 days, 2.3kg; (ii) 7-30 days, 2.8kg and (iii) 30-90 days, 4kg. The principal finding at necropsy was white muscle disease (WMD). The WMD lesions, suggested selenium (Se) deficiency was present in 49 out of the 74 kids evaluated in this study (P<0.05). In many cases, muscular dystrophy was present with other pathological conditions. Enteric and pneumonic conditions were also important causes. In the small intestine villus atrophy was observed in 14 of the 25 kids that died with enteric problems between 8 and 30 days of age. Pneumonic lesions were present in 12 out of 74 kids. Miscellaneous conditions as starvation (five cases), hepatic conditions (three cases), omphalophlebitic infection (two cases) were also present in lower proportions. In conclusion, WMD was considered the main cause of deaths in goat kids between 8 and 90 days of age. Evaluation of Se status of soil, forages and goat tissues is recommended.

中文翻译：

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墨西哥高原奶山羊幼崽死亡的主要原因

研究了墨西哥高原广泛条件下儿童死亡的原因。儿童（0-7 天）的围产期死亡率低于其他年龄组（8-90 天）的死亡率（P<0.05）。动物死亡时体重极低，(i)组0-7天，2.3kg；(ii) 7-30 天，2.8 公斤和 (iii) 30-90 天，4 公斤。尸检的主要发现是白肌病（WMD）。WMD 病变表明本研究中评估的 74 名儿童中有 49 名存在硒 (Se) 缺乏症 (P<0.05)。在许多情况下，肌营养不良症与其他病理状况同时存在。肠道和肺炎疾病也是重要原因。在 8 至 30 日龄因肠道问题而死亡的 25 名儿童中，有 14 名观察到小肠绒毛萎缩。74 名儿童中有 12 名存在肺炎病变。其他情况如饥饿（5 例）、肝脏疾病（3 例）、脐静脉感染（2 例）的比例也较低。总之，大规模杀伤性武器被认为是 8 至 90 日龄山羊儿童死亡的主要原因。建议对土壤、牧草和山羊组织的硒状况进行评估。