作　　者： ; ; ; ;

机构地区： 西南大学生命科学学院

出　　处： 《水生生物学报》 2007年第4期557-562,共6页

摘　　要： 为研究饲料碳水化合物水平对南方鲇免疫力的影响,配制含0%、15%和30%糊化玉米淀粉的等能饲料分别作为对照、中水平和高水平碳水化合物(CHO)饲料,以体重为20.7±0.5g的南方鲇幼鱼为实验对象,在水温27.5±0.2℃的条件下以对照饲料驯化15d后,测定以3种饲料投喂02、、48、、12和16周时南方鲇鱼体的血清溶菌酶活性、抗菌活性和血清总蛋白含量。结果发现,中水平CHO组血清溶菌酶活性在4周和12周时显著低于对照组(p<0.05),其他各时间点均与对照组无显著差异;高CHO组在2—12周期间均显著低于对照组(p<0.05),而在16周时与对照组之间差异不显著。从第4周到第16周,中、高CHO组血清抗菌活性均显著低于对照组(p<0.05),而中、高CHO组之间在各时间点均无显著差异。在16周时,中CHO组和高CHO组血清总蛋白含量显著高于对照组(p<0.05),在其余时间点三组间差异均不显著。以上结果表明:饲料中含15%的CHO对南方鲇生长无显著影响,但明显抑制了鱼体免疫力,且免疫抑制作用随碳水化合物水平的提高而加强。综合分析本研究的结果提出,饲料碳水化合物是抑制南方鲇免疫力的一个重要因子。提高溶菌酶类蛋白质的合成速率是该种鱼在长期饲料CHO营养胁迫下的适应机制之一,表观上反映为血清蛋白含量的升高。通过比较观察饲料CHO对南方鲇生长和免疫力的抑制作用,提出应当综合二者的观测结果来评价CHO饲料对鱼类的营养胁迫及适合状况。 To study the effect of dietary CHO level on immunity in the southern catfish, the serum lysozyme activity, antibacterial activity and total serum protein concentration were measured in the fish fed with the control, middle level and high level carbohydrate （CHO） diets containing 0% , 15% and 30% gelatinized corn starch, respectively. The southern catfish, Silurus meridionalis Chen （20.7 ±0.5）g were acclimated with the control diet for 15d at 27.5 ±0.2℃. The feeding growth experiment lasted for 0, 2, 4, 8, 12 and 16 weeks in the recirculated water system. The lysozyme activity in the fish at middle CHO level was significantly lower than that in the control group only at the 4th and the 12th week （p 〈 0.05） ,and lysozyme activity in the fish at high CHO level was significantly lower than that in the control group from the 2^nd week to the 12th week （p 〈 0.05）, while no significant difference was found between the two groups at the 16th week. Antibacterial activity in the fish at either middle or high CHO level was significantly lower than the control from the 4th to 16th week （p 〈 0.05 ）, but there was no significant difference between the former two groups. The total serum protein concentration in the fish at high CHO level and the middle CHO level were significandy higher than the control only at 16th week （p 〈 0.05） ,and there was no significant difference among the three groups at other sampling time. Although negative influence of dietary CHO of 15 % on immunity was observed in the southern catfish, growth performance was nor affected. And the negative influence increased with increasing CHO level. It can be concluded that the CHO is an important factor that restrains the immunity in the southern catfish. Accelerating synthesis of lysozyme protein should be one of the adaptive mechanisms in the fish under a long term of dietary CHO stress, which resulted in the increased serum protein. The results indicated that an optimum carbohydrate diet should be evaluated by examining i

关 键 词： 南方鲇 碳水化合物 溶菌酶活性 抗菌活性 血清蛋白

领　　域： [农业科学] [农业科学] [农业科学] [农业科学]