Study on Hatching Rate of Artemia fanciscana Cysts in Different Sources of Saline

A comparison of Arternia cysts hatching （Artemia franciscana） were conducted on bleaching and non-bleaching with sodium hypochloride on five dilution of salt solution by using sea water, sea salt solution, artificial sea salt solutions, iodine added cooking salt solution, and rock salt solutions. All solutions were adjusted at 30 ppt of salinity in 1 litter cylinder. The experiment was carried out with Factorial Experiment in CRD. After 24 hours, a randomized count of living Artemia was taken a photograph of Artemia size by stereo microscope. A statistic analysis showed that all data of bleaching and non-bleaching were no significant difference （P 〉 0.05）. The hatching ability of Artemia cysts in solutions was examined and the results showed that sea salt solution was 327.33 × 103.4. 28,536.5263 Nauplii/liter, sea water 316 ×10^3± 20,420.5779 Nauplii/liter, artificial sea salt solutions 314.33× 10^3 ± 34,268.5473 Nauplii/liter, iodine added cooking salt solution 309.66 ± 10^3 .4- 22,898.3260 Nauplii/liter, and rock salt solutions 305.33 ± 10^3 ± 25,579.9401 Nauplii/liter, respectively. The body length of Artemia was compared and the data showed that there was no significant difference （P 〉 0.05）. The highest body length was found in sea salt solution 527.32 ± 4.70μm, sea water 521.65±8.51 μm, artificial sea salt solutions 522.08 ± 10.04 μm, iodine added cooking salt solution 522.67 ±7.87 μm, and rock salt solutions 516.33 ±11.15μm, respectively.

Effects of Dietary Straw Content on Growth and Development of Locusta migratoria and Its Egg Hatching

[Objectives]This study was conducted to investigate the effects of dietary straw content on the growth and development of oriental migratory locusts(Locusta migratoria),as well as the effects of temperature and substrate on their egg hatching.[Methods]The eggs of oriental migratory locusts were hatched at 15,20,25,30,35,and 40℃in sawdust,soil and sawdust+soil conditions,respectively,to determine suitable environmental conditions for artificial hatching of oriental migratory locusts.Rice straw was added at 0%,20%,40%,60%,80%and 100%to the basic diet,and the obtained diets was feed to oriental migratory locusts at the 4^(th)instar,to investigate the effects on their growth and development.[Results]The eggs of oriental migratory locusts had a good hatching rate at 25-30℃,and sawdust was the best choice for their hatching substrate.Adding 40%of rice straw to the diet could ensure the normal growth and development of oriental migratory locusts while consuming as much rice straw as possible.[Conclusions]This study explored a technical solution for efficiently producing insect protein from discarded crop straw(treating waste with insects,and turning waste into treasure),providing support for breeding of oriental migratory locusts and locust disaster prevention.

Effects of Varying Temperature and Constant Temperature on Hatching Result of Fertilized Peacock Eggs

In order to investigate the effect of temperature on hatching result of fertilized peacock eggs, they were hatched under conditions of varying temperature and constant temperature respectively. The result shows that the hatching rate in the varying temperature treatment group （Group Ⅰ） is higher than that in the constant temperature treatment group （Group Ⅱ）. It suggests that the varying temperature treatment （high temperature in the early period, medium temperature in the middle period, slightly lower temperature in the late period, and slightly higher temperature in the hulling period） is in line with the optimum temperature variation in the hatching of fertilized peacock eggs, contributing the hatching of fertilized peacock eggs.

Ecological Hatching Method for Misgurnus anguillicaudatus Fingerlings

[Objective]To improve the artificial propagation technique of Misgurnus anguillicaudatus,and to provide technical support for the industrialization development of M.anguillicaudatus in future.[Methods] The hatching rates,survival rates,deformity rates and parent morality rates of M.anguillicaudatus were compared by ecological hatching method and traditional hatching method.[Results]The hatching rate by ecological hatching method was 32.60% higher than that by traditional hatching method,showing extremely significant differences.The survival rate of M.anguillicaudatus fingerlings by ecological hatching method was2.32% higher than that by traditional hatching method.And the deformity rates of M.anguillicaudatus fingerlings by traditional hatching method and ecological hatching method were 26.50% and 24.14%,respectively,indicating no significant differences.The morality rates of female parents of M.anguillicaudatus were89.72% and 5.91% by traditional hatching method and ecological hatching method,respectively.[Conclusions]Ecological hatching method effectively improved the hatching rate and fingerling survival rate of M.anguillicaudatus,and reduced the morality rate of female parents,which was helpful to save the production cost,met the requirements for large-scale production of M.anguillicaudatus,and had good application prospect.

Studies on Pattern of Producing Transgenic Fish II. Several Elements Related to the Establishment of Transgenic Fish

A recombinant plasmid (pcMTsGH) containing the common carp methlothionein promoter (cMT) and salmon growth hormone gene (sGH) was microinjected into common carp fertilized eggs and embryos to optimize the conditions for producing transgenic fish. Several key elements were found to have significant effects on the integration of exogenous gene. These elements include forms and doses of pcMTsGH gene microinjected, stages of embryo at which microinjection conducted and pretreatment of fertilized eggs for microinjection. The results show that, in producing transgenic fish, (1) the best time for microinjection is late onecell stage, (2) the most appropriate dose of pcMTsGH gene for microinjection is around 106～107 copies; (3) the hatching rate rises up when the gene is microinjected into the eggs whose chorions are removed, but the integration rate has no significant changes before and after the removal of egg chorions.

Shape change in viable eggs of the collembolan Folsomia candida provides insight into the role of Wolbachia endosymbionts

The endosymbiotic bacteria of the genus Wolbachia that infect the collembolan species Folsomia candida are responsible for facilitating parthenogenetic reproduction in their hosts. This study made empirical observations of the development of eggs of F. candida which contained normal populations of Wolbachia and of eggs which were cured of Wolbachia by treatment with the antibiotic rifampicin. A marked increase in egg size accompanied by a significant change in shape from spherical to discoid occurred in viable eggs three to four days after laying. These changes did not occur in the universally inviable eggs which came from the antibiotic treatment or in the 7% of untreated eggs which were naturally inviable. We infer that Wolbachia plays a critical role in zygotic or embryonic development during or before the first three days after laying and we draw on existing knowledge in speculating on the developmental mechanisms that Wolbachia may influence.

Biological Effects of Low Energy Ar^+Ion Bombardment on Silkworm Eggs:a Novel Animal Model

In this study, we found for the first time that silkworm eggs were able to survive in vacuum for a long period of time. Subsequently, 10w energy Ar＋ ions with different energies and fluences were used to bombard silkworm eggs so as to explore the resulting biological effects. Results showed that （i） the exposure of silkworm eggs to vacuum within 10 rain did not cause significant impact on the hatching rates, while the irradiation of silkworm eggs by Ar＋ ions of 25 keV or 30 keV with fiuences ranging from 2.6×2.6× 10^15 ion/cm2 to 8×2.6 × 10^15 ion/cm2 caused a significant impact on the hatching rates, and the hatching rates decreased with the increase in the fluence and energy level; （ii） the irradiation of silkworm eggs by Ar＋ ions of 30 keV with a fluence of 8×2.6 × 10^15 ion/cm2 or 9×2.6 × 10^15 ion/cm2 resulted in a noticeable etching on the egg shell surface which could be observed by a scanning electron microscope; and （iii） the irradiation of silkworm eggs by Ar＋ ions of generated several mutant phenotypes which were 30 keV with a fiuence of 9×2.6× 10^15 ion/cm2 observed in the 5th instar silkworms and a moth.

Effects of Increased Salinity on Growth, Development and Survival in Early Life Stages of the Green Toad Bufotes variabilis (Anura: Bufonidae)

This study examined the effects of increased salinity on growth, development and survival of the Green toad, Bufotes variabilis during embryonic, hatching and early larval periods. Eggs from a single cohort of B. variabilis were subjected to acute and chronic toxicity tests for water salinity ranging from 0.20 to 10 g of salt per liter. Results obtained from this study showed that salinity over 3.70 g/l increased embryonic mortality and reduced percentage of hatching and survival rate of larvae. As larvae tolerated salinity 0.20 to 3.70 g/l with highest survival, but salinity of 10 g/l caused mortality of all individuals within 12 h, 7.70-8.70 （g/l） within 4.5 days, 5.70-6.70 g/l within 10 days and 4.70 （g/l） were tolerated within 14 days. Salinity less than 0.70 g/l did not affect survival and hatching success of the embryos. After a 3-week experiment, size of larvae exposed to salinities over 0.70 g/l was lower compared to larvae reared at lower salinity levels. Meanwhile increases in salinity more than 3.70 g/l caused extension in the hatching period. Larvae reared at salinity of 3.70 to 4.70 g/l had morphological abnormalities, such as distortion of tail.

A review of gynogenesis manipulation in aquatic animals

Gynogenesis is an established technique to generate all female type offspring and this technique has been successfully induced diploid gynogens progeny in aquatic animals of fishes and crustaceans.Monosex culture of all female shrimp and fishes were selected attribute to all female type offspring which have better size than male and help increase the market size and profitable.This article discusses on the protocol applied to produce gynogens progeny and the successful rate of gynogenesis production in fishes,molluscs and aquatic crustaceans of shrimps in general.Overall most of the UV length applied for irradiated the sperm were around 254-365 nm for(20-40 s),(20-80 s)and(5-8 s)for shrimps,254 nm,30 s for molluscs species and for fishes were around 254 nm for(1.5min)and(2-12 min)time of exposure respectively.For gynogenesis induction,the fertilized eggs were treated with cold shock,heat shock or cytochalasin-B for both shrimp and fishes gynogens technique.Fertilization rate was identified around 4.33%-19.67%in shrimp.Successful hatching rate was identified around 3.0%,14.9%-37.2%of gynogens offspring in shrimp and various percentages of hatching rates were identified from each species of fish gynogens.Overall,there is still low survival rate of gynogens produced using gynogenesis technique and further study should be carried out to improve the gynogens production.The discussed protocols serve as a guide lines for the gynogenesis technique application of all female monosex culture in the future.