后抗生素时代生物饲料添加剂研发状况与对策

通过分析饲用酶制剂、饲用肽、饲用微生态制剂及植物提取物4类重要生物饲料添加剂产品研发技术和国内外生产应用现状,提出了我国主要生物饲料添加剂研发的目标与对策:重视微生物和基因资源研究,鼓励源头创新性研究;重点支持以生物技术为主的饲料添加剂研制平台建设,扶持培养高水平的人才团队;主攻关键产品研制技术,引导生物饲料添加剂技术与产业健康发展。     

Effects of different feed stimulants on freshwater crayfish (Procambarus clarkii), fed diets with or without partial replacement of fish meal by biofeed

The feeding trials were carried out with freshwater crayfish (Procambarus clarkii) to evaluate the three feed stimulants betaine (Bet), squid extract (SE) and squid meal (SM) upon fish meal (FM) diets or biofeed (BF) diets in which FM were partially replaced by BF. Results showed the three feed stimulants had no significant effect on growth. By the relative concentration of markers in the faeces and diets, the preference for each diet was estimated, and the best stimulant was the mixture of Bet, SE and SM. As FM replaced by BF increased, added with the mixture, the relative weight gain showed an increasing trend, but decreased significantly by 30% replacement. With the substitution increasing, trypsin activities increased, whereas decreased too upon 30% substitution. Less than 30% replacement, there was no significant effect on muscle proximate composition, intestine amylase activities and serum haemocyanin contents, except the drop of lipid. The results indicated that the mixture of Bet, SE and SM could perform well as a feed stimulant. And with the addition of the mixture, FM in the diet could make about no more than 20% saving without any adverse effects.