Microsatellite-Based Genetic Structure and Differentiation of Goldfish (Carassius auratus) with Sarcoma

Ten microsatellite loci were used for analyzing six populations of goldfish (Carassius auratus) with sarcoma. It showed that there was the highest genetic diversity among the white oranda with red cap (RC) population, and the lowest among the white tigerhead (WT) population. However, the outcross existed among every population. There was huge genetic differentiation between WT and the other four populations. The average observed heterozygosity (HO) among populations ranged from 0.3571 to 0.7381. And significant genetic difference (FCT = 0.1891, P = 0.0186) appeared among goldfish varieties which can be classified into three groups (RT, WT;RL, BL, YC;RC). The software Principal Coordinate Analysis (PCA) and STRUCTURE showed that significant genetic differences were revealed between RC population of goldfish and other five populations.

Preliminary Study on the Histology in the Head Sarcoma of Goldfish (Carassius auratus)

The sarcoma structure of goldfish was first analyzed by frozen section technique. The present study revealed the alkaline and acid phosphatase distribution in the head sarcoma of goldfish. And the histochemical staining in situ by calcium-cobalt method and lead nitrate method displayed a large amount of alkaline and acid phosphatases in the head sarcoma, with higher enzyme activity. The alkaline and acid phosphatases belong to hydrolases, which are widely present in various tissues. The results showed that the activity of external sarcoma is similar to the middle one, while there was more alkaline phosphatase near to the tissue sarcoma under the goldfish scales. And they have the strong activity. The study will lay the theoretical basis on enhancing the ornamental value of goldfish.

Growth and fatty acid composition of discus fish Symphysodon haraldi given varying feed ratios of beef heart,duck heart,and shrimp meat

A 56 days experiment was carried out to examine the effects of nine different diets on the growth and biochemical composition of discus fish Symphysodon haraldi tissues.Nine different types of diets were created using three main ingredients(beef heart,duck heart,and shrimp meat)in varying proportions,i.e.,10:0:0(F1),9:0:1(F2),8:0:2(F3),6:2:2(F4),4:4:2(F5),2:6:2(F6),0:8:2(F7),0:9:1(F8)and 0:10:0(F9).As the proportion of beef heart within the diet decreased,the specific growth rates(SGR),length growth rates(LGR),and height growth rates(HGR)of S.haraldi first decreased(F1-F3),then increased(F4-F6),and thereafter decreased(F7-F9),while the feed coefficient rates(FCR)showed the opposite trend.No significant differences in SGR,LGR,HGR,and FCR between the F1 and F6 groups were observed.The survival rates decreased with lower beef heart levels.Dietary inclusion of beef heart and/or shrimp meat often resulted in a decrease of crude protein and ash content.Dietary fatty acids(FA)associated with the F3,F8,and F9 groups showed significantly lower concentrations of 18:3n-3 and 20:5n-3 relative to the other groups.Similarly,the F7 and F9 diets and the S.haraldi these diets were fed to demonstrated low and high 20:4n-6 levels,respectively.While the F1 and F9 diets were both poor in 22:6n-3,the F1 group showed significantly higher 22:6n-3 content than the F9 group,indicating the more efficient retention and/or bioconversion of this FA by S.haraldi in the F1 group.The results of this study suggest that shrimp meat might not necessarily be added into moist feed for S.haraldi culture.Diets with up to 60%duck heart could be achieved without affecting growth,but showed some negative influence on survival rates.