Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, No. 1 Wenhai Road, Qingdao, 266237, China.
Carbohydr Polym. 2019 Dec 15;226:115254. doi: 10.1016/j.carbpol.2019.115254. Epub 2019 Aug 27.
Three trials were conducted to comprehensively evaluate the application of chitooligosaccharides (COSs) different dosages, molecular weights (MW) and degrees of deacetylation (DD) as a feed additive for Pacific white shrimp (Litopenaeus vannamei). In trial 1, COSs (3 KDa and 85% DD) at four different dosages (0.05%, 0.1%, 0.15% and 0.2%) were added to feed to investigate the appropriate dosages. The survival ratio (SR) of the shrimps was not significantly different (P > 0.05) between the control and treatment groups. The shrimps fed with 0.1% COSs supplementation exhibited the highest wet body weight (FBW), specific growth ratio (SGR), and weight gain (WG) and the lowest feed conversion ratio (FCR). In trial 2, COSs with different MW (85% DD and 0.1% dosage) were tested. Except for the group treated with the 12 KDa COSs, all shrimps fed with COSs had remarkably higher (P < 0.05) FBW, WG, and SGR and lower FCR (P < 0.05) than the control group, and shrimps fed with the 1 KDa COSs showed most positive effects. In trial 3, COSs with different DD (MW of 1 KDa and 0.1% dosage) were further studied. The different DD were DD5, DD25, DD50, DD75, and DD95. Shrimps fed COSs-supplemented diets of DD75 or DD95 exhibited higher (P < 0.05) FBW, WG and SGR and lower FCR than the other groups. The DD95 group had the highest FBW, WG and SGR and the lowest FCR, but there were no significant differences (P > 0.05) between the DD75 and DD95 groups. Moreover, for COSs supplementation, especially for the DD75 and DD95 groups, the antioxidant parameters were significantly different from those of the other groups. Furthermore, groups fed diets with COSs supplementation had higher (P < 0.05) trypsin activity than those fed control diets. In addition, immune and antioxidant gene expression and the morphology of the hepatopancreas were affected by the DD of COSs. Therefore, the additive dosages, molecular weights and degrees of deacetylation of COSs significantly affected the growth performance of the shrimps; therefore, it is particularly important to determine the optimum parameters of COSs.
进行了三项试验，以全面评估不同剂量、分子量（MW）和脱乙酰度（DD）的壳寡糖（COSs）作为饲料添加剂在凡纳滨对虾（Litopenaeus vannamei）中的应用。在试验 1 中，将四种不同剂量（0.05%、0.1%、0.15%和 0.2%）的 COSs（3 kDa 和 85% DD）添加到饲料中，以研究适宜的剂量。虾的成活率（SR）在对照组和处理组之间没有显著差异（P>0.05）。添加 0.1% COSs 组的虾湿体重（FBW）、特定生长率（SGR）和增重（WG）最高，饲料转化率（FCR）最低。在试验 2 中，测试了不同 MW（85% DD 和 0.1% 剂量）的 COSs。除了 12 kDa COSs 处理组外，所有添加 COSs 的虾的 FBW、WG 和 SGR 均显著高于对照组（P<0.05），FCR 也显著低于对照组（P<0.05），其中 1 kDa COSs 组效果最显著。在试验 3 中，进一步研究了不同 DD（MW 为 1 kDa 和 0.1% 剂量）的 COSs。不同的 DD 分别为 DD5、DD25、DD50、DD75 和 DD95。DD75 或 DD95 饲料组的虾的 FBW、WG 和 SGR 更高（P<0.05），FCR 更低。DD95 组的 FBW、WG 和 SGR 最高，FCR 最低，但与 DD75 组无显著差异（P>0.05）。此外，对于 COSs 补充，特别是 DD75 和 DD95 组，抗氧化参数与其他组有显著差异。此外，添加 COSs 饲料组的胰蛋白酶活性高于对照组。此外，免疫和抗氧化基因表达以及肝胰腺的形态受 COSs 的 DD 影响。因此，COSs 的添加剂量、分子量和脱乙酰度显著影响虾的生长性能；因此，确定 COSs 的最佳参数尤为重要。
