稻米来源镉对生长期猪的生长特性及不同脏器组织镉蓄积的影响

Effects of Cadmium Supplied via Cadmium Contaminated Rice on the Growth Performance and the Tissues Accumulation of Cadmium in Growing-finishing Pigs

环境中的镉污染对动植物及人类都带来了极大的危害。目前,多数镉毒理研究关注其无机状态,而来源于稻米的有机态镉的毒害作用报道较少。为评估稻米来源镉对生长期猪的毒性作用,选用初始体重为30 kg左右的健康生长猪28头,随机分为体重无明显差异的2组,即对照组与稻米来源镉组(试验组),研究稻米来源镉对生长期猪(生长及育肥全阶段)的生长特性及不同脏器组织镉蓄积的影响。结果表明,在生长及育肥阶段,试验组与对照组相比:1)生长特性无显著差异(P>0.05);2)育肥期组织游离氨基酸含量,除肌肉中的赖氨酸显著降低外(P<0.05),血浆、肝脏、肾脏及肌肉中其他游离氨基酸水平均无显著差异(P>0.05);3)心脏、肝脏、脾脏、肾脏、肺脏、胃、小肠、大肠、骨骼中镉蓄积量显著增高(P<0.05),而肌肉、血液中无显著差异(P>0.05),脂肪、皮中未检出镉。日粮使用大比例镉超标稻米后镉在各脏器和组织中的蓄积规律为肾脏>肝脏>小肠>脾>肺>大肠>胃>血液>骨头>心>腿肌>背肌>脂肪、皮。由此可见,镉超标稻米对生长期猪的生长特性未产生显著的影响,稻米来源镉主要蓄积于肝脏和肾脏,而主流食用组织肌肉和血液中镉的蓄积量较少。

Cadmium pollution in the ecological environment raises great harm to plants, animals, and humans. Tox- icological studies on cadmium mainly focus on its inorganic state, while toxic effects of cadmium from the organic state of rice are obscure. In order to evaluate the effects of dietary cadmium excessive rice on the growth perform- ance and accumulated pattern in tissues of growing pigs, twenty-eight healthy growing pigs with similar body weight （30 kg） were housed individually and randomly assigned to two groups （14 pigs per group）. The results showed that： 1） There were no significant differences on growth performance in cadmium excessive rice diet pro- vided group （P〉 0.05）; 2） The concentration of lysine in muscle reduced significantly in test fattening-pig group （P 〈 0.05）, and no differences were found on the free amino acids in plasma, liver, kidneys, and muscle （P〉 0.05）; 3） Significant differences were noticed in most tissues （heart, liver, spleen, kidney, lung, stomach, small intestine, large intestine and bone） （P〈 0.05） apart from the blood and muscle for the accumulated cadmium （P〉 0.05）. No cadmi- um was detected in fat and skin in both groups. The order of the tissues accumulation was that kidney 〉 liver 〉 small intestine 〉 spleen 〉 lung 〉 large intestine 〉 stomach 〉 blood 〉 bone 〉 heart 〉 leg muscle 〉 dorsi muscle 〉 fat/skin. In conclusion, the use of cadmium excessive rice in growing and fattening pig diets has little effect on the growth performance. The cadmium accumulation in liver and kidney were significantly increased but no difference was found in edible meat and blood tissues.