不同人工饲料对龟纹瓢虫取食效应和虫体成分的影响

Effects of Artificial Diets on Female Propylea japonica's Feeding and Body Composition

研究了5种人工饲料对龟纹瓢虫雌虫取食以及体成分的影响.结果表明：人工饲料喂养组和蚜虫喂养组的取食量变化趋势相同,都是在羽化后几天内取食量急剧升高,然后逐渐减弱;并且蚜虫喂养组的取食量和取食指数都远大于人工饲料喂养组,约为人工饲料喂养组的3~4倍;而添加蔗糖的饲料2组的取食量要显著高于未添加的饲料1组,则证明了蔗糖对于龟纹瓢虫的取食具有促进作用;在相对生长率（RGR）和食物近似消化率（AD）上,蚜虫喂养组要显著高于人工饲料喂养组,人工饲料喂养组的食物近似消化率偏低,可能是由于饲料的营养配比不平衡,或是饲料中存在某些抗营养因子;而对食物利用率（ECI）和转化率（ECD）的测定发现蚜虫喂养组要低于人工饲料喂养组,这可能是低取食量的昆虫通过提高食物利用率和转化率来维持其生存的需要;实验还表明添加蔗糖可以显著提高食物的近似消化率、食物利用率和转化率.同时对其体成分的研究表明：龟纹瓢虫雌虫水分、粗蛋白和粗脂肪的含量分别为58.77%,15.93%和11.30%;雌虫的脂肪酸组成以不饱和脂肪酸（USFA）为主,单不饱和脂肪酸（MUFA）以油酸（1C18n-9）为主要组成成分,而多不饱和脂肪酸（PUFA）以亚油酸（2C18n-6）占的比例最大;在饲料中添加蔗糖能显著提高龟纹瓢虫的蛋白含量,而在饲料中添加橄榄油则能显著提高龟纹瓢虫粗脂肪的含量;人工饲料组的USFA（平均为72.70%）要高于蚜虫喂养组的含量（58.00%）,当添加0.5%的橄榄油时能显著提高USFA的含量,特别是油酸的含量增加明显,这与橄榄油中油酸含量丰富密切相关.

This paper studied the effects of artificial diets on the female Propylea japonica＇s feeding and body composition. And the results indicated that the feeding amount of ladybird increased sharply at the initial days after eclosion, and then decreased gradually. The feeding amount and the consumption index （CI） of the beetles fed on cotton aphid were three to four times higher than that of the beetles fed with artificial diets. The feeding amount of the beetles fed with diet containing sucrose was significantly higher than that of the beetles fed with diets without sucrose, which proved that the sucrose had the function of increasing food intake for Propylea japonica ; As to the relative growth rate（RGR） and approximate digestibility（AD） , there existed significant difference between the control and the beetles fed with artificial diets, due to the unbalance of the nutrition or existing some antinutritional facts in the artificial diets probably. While the Efficiency of conversion of ingested food （ECI） and the efficiency of conversion of digested food （ECD） in the control were significantly higher than that in beetles fed with artificial diets, which was probably the strategy of the insects whose food intake was low to survive. Furthermore, the results indicated that the dietary sucrose could improve AD, ECI and ECD of the artificial diets. As to the effects of the artificial diets on the body composition, the results showed that contents of moisture, crude protein and crude fat of female Propylea japonica were 58.77% ,15.93% and 11. 30%,respectively. And the analysis of the female fatty acids indicated that unsaturated fatty acid （USFA） was the major contents. In monounsaturated fatty acids （MUFA） and the polyunsaturated fatty acids （PUFA）, the highest contents were oleic acid （1C18 n-9） and linoleic acid （2C18 n-6） respectively. The dietary sucrose could increase the content of crude protein in Propylea japonica, and the dietary olive oil could increase the content of crude fat significantly. The USFA content （72.70 %） of the beetles fed with artificial diets was higher than that of control （58.00 %）. Supplementing 0.5% olive oil in diet could remarkably in- crease the content of USFA,specially of oleic acid （1C18 n-9）, due to the rich oleic acid content in olive oil.