Welchman D D, Whelehan O P, Webster A J
Department of Animal Husbandry, University of Bristol School of Veterinary Science, Langford.
Vet Rec. 1988 Nov 12;123(20):505-10. doi: 10.1136/vr.123.20.505.
Calves were reared for veal and fed milk replacer either alone or with straw or dry feed of varied iron content. Measurements of haematology and iron biochemistry were made at the start of the rearing period and before slaughter at 16 to 20 weeks of age. When the total dietary iron intake rose to approximately 12,500 mg (an average of 112 mg/dl, approximately 60 mg/kg dry matter) haemoglobin concentration reached a mean value (+/- sd) of 12.4 +/- 1.1 g/dl, similar to control calves. There was no further increase in haemoglobin when more iron was fed, indicating that there was sufficient iron in the diet for normal erythropoiesis. The borderline of iron deficiency anaemia at 16 to 20 weeks of age was defined as a haemoglobin concentration of 9 g/dl and a saturation of total iron binding capacity of 10 per cent. There was evidence of diurnal variation in serum iron concentration in calves fed in a periodic manner. The feeding of straw to veal calves did not prevent iron deficient erythropoiesis.
犊牛饲养用于生产小牛肉，单独或以不同铁含量的稻草或干饲料喂养代乳品。在饲养期开始时以及16至20周龄屠宰前进行血液学和铁生物化学测量。当总膳食铁摄入量升至约12500毫克（平均112毫克/分升，约60毫克/千克干物质）时，血红蛋白浓度达到平均值（±标准差）12.4±1.1克/分升，与对照犊牛相似。饲喂更多铁时血红蛋白没有进一步增加，表明日粮中有足够的铁用于正常的红细胞生成。16至20周龄缺铁性贫血的临界值定义为血红蛋白浓度9克/分升和总铁结合力饱和度10%。有证据表明，定时饲喂的犊牛血清铁浓度存在昼夜变化。给犊牛饲喂稻草并不能防止缺铁性红细胞生成。
