Allometric Growth Of Chum Salmon Larvae And Effects Of Strontium On Physiological Indices Of Their Juveniles

Chum salmon （Oncorhynchus keta） which is also called the Pacific salmon，belonging to Salmoniformes（Salmoniformes），Salmon suborder （Salmonoidei），Salmonidae （Salmonidae），Pacific salmon（Oncorhynchus），live in the north latitude35°north of the Pacific Ocean and coastal rivers，for tracing the rivermigratory fish. Chum salmon in China distributed in Heilongjiang River and its tributaries Wusulijiang River，suifenhe river，and tumenjiang river water system. Because in recent years for chum salmon over fishing andpollution of the environment，its resources are serious failure，therefore，has caused the attention of the whole fishsource countries around the world，not only from the perspectives of ecology，genetics and climate change，studied the salmon，but also for the salmon to large-scale breeding，breeding discharge technology research andevaluation.From two aspects，this paper studied the salmon: first，by using the method of experimental ecology of chumsalmon in the yolk-sac stage larvae of allometric growth and organ development priority in early life and make theecological environment to adapt to carried on the thorough system’s research； Second，under laboratoryconditions，using the method of long-term exposure concentration of strontium (Sr²⁺) set up four groups，10mg/L，20mg/L，30mg/L and40mg/L，respectively，meanwhile set up blank control group，and strontium(Sr²⁺) wasstudiedinchumsalmon，summedupthegrowthofsurvival，muscleantioxidantenzymes，appeaseand AKP activity. The results are as follows:1. The results are indicated Feeling, feeding, breathing and swimming organ of salmon yolk-sac larvae such asthe rapid differentiation, many of the key organs there are allometric phenomenon. In all parts of the body, the headand tail of a positive allometric growth, the trunk negative allometric growth, body height first and then decreases;organs of the head, eye diameter, wide mouth, snout length and eyes behind long are positive allometric; swimmingorgans, pectoral and pelvic fins, dorsal fin, anal fin, dorsal fin base, anal fin base and caudal fins are positive allometricgrowth, adipose fin is negative allometric, where pelvic fins in the whole25.31mm long,12-day-old growthinflection point, but before and after the inflection point are positive allometric. Salmon yolk sac larvae sensory organs,the rapid development of the feeding organs, respiratory organs and swimming organs, resorted film after the larvaehave to survive early plays an important role in a variety of capacity for the shortest time. More organs quickly afterthe completion of the development, the rapid increase in the larvae actively feeding and avoiding predators the ability to quickly adapt to the complexity of the external environment.2. Chum salmon T-SOD activity in terms of muscle tissue and the control group had a significant difference （P<0.05）. When strontium (Sr²⁺) concentration increased to20mg/L，the chum salmon muscle tissue in the T-SOD activity is significantly induced，as elevated strontium (Sr²⁺) concentration on T-SOD showed inhibitoryeffect，and this inhibition has a tendency to increase with concentration increasing，but T-SOD activity is still higherthan that of control group （P <0.05）. Strontium (Sr²⁺) to CAT activity of chum salmon muscle stimulationinduced effect. When dealing with concentration of10mg/L and20mg/L，CAT activity and the control group nosignificant difference （P>0.05），with the increase of treatment concentration increased CAT activity. Except40mg/L concentration group，different strontium (Sr²⁺) concentration leads to chum salmon muscle activity ofGSH-PX and the control group with significant difference （P <0.05），when the concentration of strontium(Sr²⁺) increased to30mg/L，the GSH-PX activity induced by maximum amplitude，40mg/L concentrationgroup of inhibiting the activity of GSH-PX，and there was no significant difference with control group （P>0.05）.Strontium (Sr²⁺) to GST activity impact and impact on the activity of GSH-PX are similar. There is significantdifference in the control group （P <0.05）.3. In strontium (Sr²⁺) set the dose range，the chum salmon in the experimental group summed up all cangrow，but in the quality of strontium (Sr²⁺) concentration is higher，chum salmon youth growth and survivalrate are different degrees of inhibition，strontium (Sr²⁺) massconcentrationfor10mg/L，thegrowthindexandthe highest survival rate. Treatment group of chum salmon muscle Ca²⁺-ATPase activity and the control group with asignificant difference （P <0.05）. Treatment group of Ca²⁺-ATPase activity under the induction of strontium(Sr²⁺) increasedsignificantly，butasthestrontium (Sr²⁺)，withtheincreaseofaddingamountofCa²⁺-ATPaseactivity has a downward trend. Strontium (Sr²⁺) half of chum salmon fish Na+/K+-ATPase activity have asignificant effect （P <0.05）. Add strontium (Sr²⁺) group of Na+/K+-ATPase activity was significantly lowerthan control group，and as the strontium (Sr²⁺)，with the increase of adding the amount of Na+/K+-ATPaseactivity was gradually reduced. Strontium (Sr²⁺) has a significant effect on chum salmon AKP activity （P <0.05），and Na+/K+-ATPase activity of similar changes. AKP activity of the treatment group was significantly lowerthan the control group，and as the strontium (Sr²⁺)，with the increase of adding amount of activity of AKPgradually reduces，illustrate the strontium (Sr²⁺) content is higher，the stronger the inhibition activity of AKP.Results suggest that in the chum salmon summed up long-term exposure experiments of strontium (Sr²⁺)concentration of safety and quality should be controlled within10mg/L.4. Using tissue section techniques, studied the sr for salmon summed up the influence of the liver and kidney, theexperiment was carried out for30days, the results show that sr for salmon summed up the liver has a certain influence,of the control group,10mg/L and20mg/L group of young fish liver nuclei size uniformly thick and well-defined,liver tissue had no obvious change,30mg/L group and40mg/L, summed up some liver nuclei, nuclear structurefuzzy. This shows, with the increase of concentrations of strontium and began to produce some side effects. Livertissue of strontium is not found in this study microstructure structure has obvious effect to the kidney.