含重组人乳铁蛋白乳粉蛋白质营养学评价

Evaluation of protein nutritional value of SD rats fed milk powder containing recombinant human lactoferrin derived from transgenic cloned cattle

目的评价牛乳腺生物反应器表达的重组人乳蛋白乳粉蛋白质的营养价值。方法选用100只清洁级刚断乳（出生后20-23 d）SD大鼠（雌、雄各半）,按性别、体质量随机分为5组：重组人乳蛋白乳粉组、普通乳粉组、酪蛋白乳粉组、牛乳铁蛋白乳粉组、重组人乳铁蛋白乳粉组,分别喂饲相应饲料28 d,观察大鼠的进食量、体质量,测定血常规、血生化情况,试验末期处死动物,称量脏器重量并对脏器进行病理学检查,计算蛋白功效比和校正蛋白功效比,对氨基酸评分。结果重组人乳铁蛋白乳粉雄性动物组总体蛋白功效比值差异有统计学意义（P〈0.05）,但重组人乳铁蛋白乳粉组雄性和其他对照组差异无统计学意义（P〉0.05）。雌性动物重组人乳铁蛋白乳粉组和其他对照组蛋白功效比值差异无统计学意义（P〉0.05）。结论重组人乳铁蛋白乳粉的蛋白功效和其他组相比并无较大区别,氨基酸评分结果显示苯丙氨酸和酪氨酸为第一限制氨基酸,与普通乳粉一样。

Objective To evaluate the protein nutritional value fed milk powder containing recombinant human lactoferrin derived from transgenic cloned cattle. Methods Based on gender and weight,100 weanling SD rats were randomly divided into five groups,casein normal control group,recombinant human lactoferrin milk powder group,normal milk powder control group,recombinant human lactoferrin reference group,cattle lactoferrin reference group. They were fed for28 d. Bodyweight and food consumption were observed,hematology and clinical biochemistry were measured during the experiment period. The rats were sacrificed at the end point for organ weight measurement and pathological examination.The protein efficiency ration and amino acid score were calculated. Results The protein efficiency ratio of rh LF milk power had no significant statistical discrepancy than other control groups in male rats. The result of the female rats was the same. The data of amino acid score of rh LF milk power and normal control group are slightly different. Conclusion The protein efficiency ratio of rh LF milk power equalaled the other milk powder groups. The protein amino acid score of rh LF milk powder showed PHE and TYR were the first limited amino acid.