The effect of selenium on antioxidant system in aquaculture animals.

There will be generated some adverse conditions in the process of acquculture farming with the continuous improvement of the intensive degree of modern aquaculture, such as crowding stress, hypoxia, and malnutrition, which will easily lead to oxidative stress. Se is an effective antioxidant, participating and playing an important role in the antioxidant defense system of fish. This paper reviews the physiological functions of selenoproteins in resisting oxidative stress in aquatic animals, the mechanisms of different forms of Se in anti-oxidative stress in aquatic animals and the harmful effects of lower and higher levels of Se in aquaculture. To summarize the application and research progress of Se in oxidative stress in aquatic animals and provide scientific references for its application in anti-oxidative stress in aquaculture.

[Identification of released population of Japanese flounder based on stable isotopes analysis]. / åŸºäºŽç¨³å®šåŒä½ç´ æŠ€æœ¯çš„å¢žæ®–æ”¾æµç‰™é²†ç¾¤ä½“é‰´åˆ«.

Japanese flounder (Paralichthys olivaceus) is an important releasing fish in the Yellow and Bohai Seas of China. The identification of wild and releasing population is the premise to evaluate the enhancement effects. In order to study the application of stable isotope in the identification of released P. olivaceus population, captured juveniles in the offshore releasing area of Qinhuangdao were distinguished into wild and released population using previous method (combination of morphology and molecular). Then, the contents of carbon and nitrogen stable isotope in muscle and otoliths (including the whole and the core region) were measured. The cultured population was set as control. The results showed that δ13C values (wild population: -17.19‰±0.73‰; released population: -17.10‰±0.61‰; cultured population: -20.75‰±0.07‰) and δ15N values (wild population: 11.81‰±0.38‰; released population: 11.62‰±0.48‰; cultured population: 8.64‰±0.60‰) of muscle and δ13C value (wild popu-lation: -4.47‰±0.35‰; released population: -4.63‰±0.29‰; cultured population: -6.59‰±0.58‰) of the whole otolith could be used to identify the cultured population, but could not be used to distinguish the wild from the released population. The δ13C value (wild population: -4.66‰±0.30‰; released population: -5.41‰±0.21‰; cultured population: -5.37‰±0.19‰) of the core region of otolith could be used to identify the wild popu-lation. The δ18O values of the whole and the core region of otolith from these three groups were overlapped and could not be used to distinguish different populations. Our results indicated that the δ13C value of the core area of otolith could be used to identify wild and released population, with application prospect in the identification of broodstocks participating in spawning migration. This study provided basic data and technical methods for evaluating early resources replenishment and the effects of Japanese flounder enhancement.

[Effects of echinacoside on extracellular acetylcholine and choline levels of hippocampus and striatum of cerebral ischemia rats].

The aim of this study is to investigate the effect of echinacoside (ECH) on cholinergic neurotransmitter extracellular of hippocampus and striatum and its possible mechanisms of neuro-protective effect against vascular dementia rats. In this study brain microdialysis technique combined with HPLC-IMER-ECD (high-performance liquid chromatography-immobilized enzyme reactor-electrochemical detector) was used. The bilateral common carotid arteries occluded in two times operation at 72 h interval for vascular dementia model rats were used and the successful vascular dementia model rats were examined by Morris water maze. The content of acetylcholine (ACh) and choline (Ch) of microdialysate extracellular of hippocampus and striatum was determined by HPLC-IMER-ECD and the AChE activity in the hippocampus was measured. The results showed that the success rate of vascular dementia model was 83.08% after six weeks; the results also showed that echinacoside and galantamine could increase the content of ACh and reduce the content of Ch extracellular of hippocampus and striatum significantly and the AChE activity increased significantly compared with that of the model group. The results suggested that echinacoside could promote the recovery of cholinergic neurotransmitter levels in vascular dementia rats' brain, which may be one of the mechanisms of neuro-protection.

Study on tandem repeat sequence variation in sheep mtDNA D-loop region.

The 75-nt-long tandem repeat sequence in the control region of mtDNA of 77 individuals, of which 69 were from different indigenous sheep breeds in China and 8 were from imported breeds, was sequenced and analyzed to investigate the origin and differentiation of Chinese indigenous sheep breeds and also the genetic diversities and relationships among them. A total of 28 variable sites were detected within 309 repeated sequences, among which 7 sites were singleton variable sites with two variants, 1 site was a singleton variable site with three variants, and 20 sites were parsimony informative sites with two variants. A total of 63 haplotypes were sorted from 28 polymorphic sites, among which two main and basic haplotypes, namely, Hap 1 and Hap 3 were present at a much higher proportion, at 12.94% and 30.42%, respectively. It could be inferred that Chinese indigenous sheep breeds originated from two maternal ancestors because of the maternal inheritance characteristics of the mtDNA. Altay sheep and Kazakstan sheep are closely related and do not differentiate significantly. Mongolian sheep and Ujumuqin sheep also share a close relationship. Tibetan sheep, Mongolian sheep, and Ujumuqin sheep have lower genetic diversity than Altay sheep and Kazakstan sheep.