生物学指标在评定养殖鲫肝脏脂肪蓄积程度中的作用

为了了解配合饲料养殖鲫肝脏中脂肪蓄积状况,以及肥满度、体质量/体长、脏体指数、肝体指数、肠系膜脂肪指数、肠道指数等6项生物学指标在评定养殖鲫肝脏脂肪蓄积程度中的作用,分别采用物理方法和索氏抽提法对30尾野生鲫和60尾配合饲料养殖鲫的生物学指标和肝脏脂肪含量进行了检测;采用HE染色法制作和观察了鲫肝脏组织切片;采用SPSS 19.0软件对生物学指标和肝脏脂肪含量的相关关系进行了统计分析.结果表明,养殖鲫的肥满度、体质量/体长、脏体指数、肝体指数、肠系膜脂肪指数、肠道指数、肝脏脂肪含量平均值均高于野生鲫;其中野生和养殖鲫肝脏脂肪含量平均值分别为2.11％±0.69％和19.49％±4.31％.肝脏组织学检查发现野生鲫肝细胞形态正常,肝细胞轮廓清晰,且沿肝细胞索有序排列,无脂肪空泡;养殖鲫的肝脏细胞形态大小不一,细胞核萎缩、溶解以及偏移细胞中央的现象比较严重,肝细胞轮廓不清,脂肪严重蓄积时可见明显脂肪空泡.养殖鲫的肥满度、体质量/体长、肠道指数均与肝脏脂肪含量之间无显著相关;但脏体指数(X1)、肝体指数(X2)、肠系膜脂肪指数(X3)均与肝脏脂肪含量(Y)存在显著中等正相关,多元线性回归方程为Y=8.085 +0.282X1+3.726 X2 +0.505X3(R =0.562,F=3.995,P=0.018).养殖鲫肝脏中脂肪蓄积现象严重,并且蓄积程度随脏体指数、肝体指数、肠系膜脂肪指数的增加而加重.

Functions of body indices in evaluating the degree of lipid accumulation in livers of cultured Carassius auratus

To understand the lipid state accumulated in livers of cultured Carassius auratus and clarify the functions of body indices in evaluating the lipid accumulation of liver,body indices including condition factor(CF),ratio of body weight to body length(W/L),viscerosomatic index(VSI),heptosomatic index(HSI),mesenteric fat index(MFI)and intestinal index(II)of thirty wild C.auratus and sixty cultured C.auratus were calculated and liver lipid content was determined by Soxhlet method.The morphology of hepatic cell was observed by method of hematoxylin and eosin stain.Relationships between body indices and liver lipid content were studied by software SPSS 19.0.Results showed that all the CF,W/L,VSI,HSI,MFI and II of cultured C.auratus were higher than those of wild C.auratus. The average liver lipid contents of wild and cultured C.auratus were 1.88%±0.69% and 19.49%±4.31%,respectively.Hepatic histology showed that hepatic cells,arranged along the hepatic cell cords,of wild C.auratus were uniform in size and most nuclei were located in the central,which indicated the normal morphology of hepatic cells.However,hepatic cells of cultured C.auratus were irregular in size and morphology,characterized by obvious nuclei migration,atrophy,unclear outline and more fat vacuoles.No significant relationship between CF and liver lipid content of cultured C.auratus was found(P>0.05).However,VSI(X₁),HSI(X₂)and MFI(X₃)all were significantly and positively related to the liver lipid content(Y)(P<0.05),and the regression equation was as follows:Y=8.085+0.282 X₁+3.726 X₂+0.505 X₃(R=0.562,F=3.995,P=0.018).It is concluded from the above that the liver lipid accumulation is very serious.The higher the VSI,HSI and MFI of cultured C.auratus,the more severe of lipid accumulation in the liver.