Substitution of silkworm pupae （Bombyx mori） for fish meal in broodstock diets for snakeskin gourami （Trichogaster pectoralis） was conducted in order to evaluate the effect of silkworm pupae on feed digestibility ...Substitution of silkworm pupae （Bombyx mori） for fish meal in broodstock diets for snakeskin gourami （Trichogaster pectoralis） was conducted in order to evaluate the effect of silkworm pupae on feed digestibility and broodstock performance. Snakeskin gourami broodfish were fed with isocaloric diets （DE 3,000 a： 50 Kcal/kg） contained 32% crude protein. The levels of substitution were 0%, 50%, 75% and 100% of protein from fish meal （equal to 0%, 14.57%, 21.75% and 29.03% silk worm by weight）. The study was assigned in CRD with 4 treatments and 3 replications. Six hundred of snakeskin gourami with five-month old and average weight of 78.67 ± 2.15 g in female and average weight of 73.00 ± 2.49 g in male were stocked in 12 cages. Fifty fishes of 25 females and 25 males were reared in each cage and fed experimental diet for five months. The result indicated that protein digestibility of test diets were significantly decrease （P 〈 0.05） according to the level of silkworm pupae in diets where as the dry matter digestibility showed no significantly different （P 〉 0.05）. The growth performance and egg fecundity were significantly decreased （P 〈 0.05） according to the levels of silkworm pupae. In contrast, egg quality in term of fry number on first spawned, fingering number on first spawned were not significantly different （P 〉 0.05）. The survival rate of one month nursing fish on first spawned were significantly different （P 〈 0.05）. Hence, silkworm pupae could substitution for 50% of protein from fish meal （14.57% by weight） in snakeskin gourami broodstock diets without any adverse effect on egg quality.展开更多
The inheritance mode of seven microsatellite markers was investigated in Patinopecten yessoensis larvae from four con-trolled crosses,and the feasibility of using these markers for kinship estimation was also examined...The inheritance mode of seven microsatellite markers was investigated in Patinopecten yessoensis larvae from four con-trolled crosses,and the feasibility of using these markers for kinship estimation was also examined. All the seven microsatellite loci were compatible with Mendelian inheritance. Neither sex-linked barriers to transmission nor major barriers to fertilization between gametes from the parents were evident. Two of the seven loci showed the presence of null alleles in two families,suggesting the need to conduct comprehensive species-specific inheritance studies for microsatellite loci used in population genetic studies. However,even if the null allele heterozygotes were considered as homozygotes in the calculation of genetic distance,offspring from four families were all unambiguously discriminated in the neighbor-joining dendrogram. This result indicates that the microsatellite markers used may be capable of discriminating between related and unrelated scallop larvae in the absence of pedigree information,and of investigating the effective number of parents contributing to the hatchery population of the Japanese scallop.展开更多
文摘Substitution of silkworm pupae （Bombyx mori） for fish meal in broodstock diets for snakeskin gourami （Trichogaster pectoralis） was conducted in order to evaluate the effect of silkworm pupae on feed digestibility and broodstock performance. Snakeskin gourami broodfish were fed with isocaloric diets （DE 3,000 a： 50 Kcal/kg） contained 32% crude protein. The levels of substitution were 0%, 50%, 75% and 100% of protein from fish meal （equal to 0%, 14.57%, 21.75% and 29.03% silk worm by weight）. The study was assigned in CRD with 4 treatments and 3 replications. Six hundred of snakeskin gourami with five-month old and average weight of 78.67 ± 2.15 g in female and average weight of 73.00 ± 2.49 g in male were stocked in 12 cages. Fifty fishes of 25 females and 25 males were reared in each cage and fed experimental diet for five months. The result indicated that protein digestibility of test diets were significantly decrease （P 〈 0.05） according to the level of silkworm pupae in diets where as the dry matter digestibility showed no significantly different （P 〉 0.05）. The growth performance and egg fecundity were significantly decreased （P 〈 0.05） according to the levels of silkworm pupae. In contrast, egg quality in term of fry number on first spawned, fingering number on first spawned were not significantly different （P 〉 0.05）. The survival rate of one month nursing fish on first spawned were significantly different （P 〈 0.05）. Hence, silkworm pupae could substitution for 50% of protein from fish meal （14.57% by weight） in snakeskin gourami broodstock diets without any adverse effect on egg quality.
基金supported by grants from the National High Technology Research and Development Program(No. 2006AA10A409)Scientific and Technical Supporting Program (No. 2006BAD09A01)Natural Science Foundation of China (No. 30571442).
文摘The inheritance mode of seven microsatellite markers was investigated in Patinopecten yessoensis larvae from four con-trolled crosses,and the feasibility of using these markers for kinship estimation was also examined. All the seven microsatellite loci were compatible with Mendelian inheritance. Neither sex-linked barriers to transmission nor major barriers to fertilization between gametes from the parents were evident. Two of the seven loci showed the presence of null alleles in two families,suggesting the need to conduct comprehensive species-specific inheritance studies for microsatellite loci used in population genetic studies. However,even if the null allele heterozygotes were considered as homozygotes in the calculation of genetic distance,offspring from four families were all unambiguously discriminated in the neighbor-joining dendrogram. This result indicates that the microsatellite markers used may be capable of discriminating between related and unrelated scallop larvae in the absence of pedigree information,and of investigating the effective number of parents contributing to the hatchery population of the Japanese scallop.
