【摘要】 为研究不同钴源对肉羊VB12营养状况的影响及其生物学效应,选24只健康、体重相近((23.6±0.8)kg)的杂交一代羯羊,饲喂加入硫酸钴、氯化钴、乙酸钴和氧化钴的试验日粮,试验期8周。结果表明:1)硫酸钴、氯化钴、乙酸钴、氧化钴的相对生物学有效率分别为100%、95.66%、89.50%和22.56%(P<0.01);2)硫酸钴、氯化钴、乙酸钴和氧化钴组血浆VB12的含量分别为1 666.91、594.51、493.3和376.1 pmol/L,硫酸钴、氯化钴组相近,乙酸钴组稍低,而氧化钴组明显下降,血浆甲基丙二酸含量为2.94、3.01、3.49和3.99μmol/L;同型半胱胺含量为8.91、9.23、9.97和10.78μmol/L,硫酸钴与氯化钴组相近,乙酸钴组稍有增加,而氧化钴组明显升高,3个指标反映了一致的钴营养状况。但4个钴源组血浆叶酸含量(18.79、17.05、17.41和16.54 nmol/L)和葡萄糖含量(3.80、3.74、3.82和3.64 mmol/L)未显差异(P>0.05);3)硫酸钴、氯化钴、乙酸钴和氧化钴组血液红细胞数分别为10.97×1012、10.97×1012、11.01×1012和9.64×1012L-1;红细胞压积为34.52%、34.67%、34.70%和32.70%;血红蛋白为107.17、106.33、106.83和98.22 g/L。前3种钴源组明显大于(P<0.05)氧化钴组,其改善机体造血机能的作用优于氧化钴。由此可见,硫酸钴、氯化钴和乙酸钴对肉羊VB12的营养状况及生物学效应相近,均高于氧化钴。更多还原

【Abstract】 The experiment aimed at studying the effects of different cobalt sources on vitamin B₁₂ status and their biological functions in sheep.Twenty four healthy wethers with an average weight of（23.6±0.8） kg were divided randomly into 4 groups and fed with different experimental diets in which the cobalt were supplied as cobalt sulphate,cobalt chloride,cobalt acetate and cobalt oxide.All animals were individually fed with a constant concentration and hay for 8 weeks.Results showed that VB₁₂ production from cobalt in lambs was similar when using cobalt sulphate and cobalt chloride,and was significantly higher（P<0.05） in cobalt sulphate than in cobalt acetate.However,VB₁₂ production significantly decreased in cobalt oxide treatment compared with other forms of cobalt sources.The relative bioavailability of cobalt sulphate,cobalt chloride,cobalt acetate and cobalt oxide was 100%,95.66%,89.50% and 22.56% respectively.Plasma concentrations of methylmalonic acid（2.94,3.01,3.49 and 3.99 μmol/L） and homocysteine（8.91,9.23,9.97 and 10.78 μmol/L） reflected similar results with those based on plasma VB₁₂ concentration.However,Plasma concentrations of folate（18.79,17.05,17.41 and 16.54 nmol/L） and glucose（3.80,3.74,3.82 and 3.64 mmol/L） could not be used to assess cobalt status.Compared with cobalt oxide,the other forms of cobalt sources had larger positive influence on animal blood production.In conclusion,cobalt sulphate,cobalt chloride and cobalt acetate were more available than cobalt oxide for sheep.更多还原