Over the past five years, an epidemic disease broke out in Pelteobagrus fulvidraco ponds of Zhejiang Province. The diseased fish mainly exhibits head splitting and surface bleeding; dissection results reveal hepatonep...Over the past five years, an epidemic disease broke out in Pelteobagrus fulvidraco ponds of Zhejiang Province. The diseased fish mainly exhibits head splitting and surface bleeding; dissection results reveal hepatonephromegaly and abdominal bleeding. A bacterial strain HSY201301 was isolated from the liver tissue of P. fulvidraco with typical symptoms. Artificial infection experiment confirmed that the isolated strain had a strong virulence to healthy P. fidvidraco, leading to similar symptoms to naturally infected P. fulvidraco. The isolated strain was identified as an Edwardsiella tarda strain according to conventional morphological, physiological, biochemical characteristics and 16S rRNA gene sequence. Results of drug susceptibility test indicated that the isolated strain was sensitive to cipro- floxacin, doxitard, penicillin, doxycycline, and rocephin. This study laid solid foundation for effective prevention and control of E. tarda.展开更多
Androgenesis was the especial zoogamy that the germ plasma of offspring was from the agnate. In this study the eggs of Yellow catfish （Pelteobagrus fulvidraco） were irradiated by UV suspending in the synthetic ovari...Androgenesis was the especial zoogamy that the germ plasma of offspring was from the agnate. In this study the eggs of Yellow catfish （Pelteobagrus fulvidraco） were irradiated by UV suspending in the synthetic ovarian fluid （OF）, and the total dosage of UV irradiation was 220 mJ·cm^-2. Diploid could be induced by heat shock （40℃, 2 min, 3 min） with different time period after fertilization （15-37 min）. The result showed that heat shock with 2 min was better than 3 min; there were two apices of induction in 17-21 min and 27-31 min after fertilization. The highest hatching rate was 3.30% at 29 min after fertilization, and the difference between two apices of induction was unobvious.展开更多
[Objectives] This study was conducted to study early reproduction techniques of yellow catfish(Pelteobagrus fulvidraco) in Jianghan Plain. [Methods] Parents of P. fulvidraco were cultured by the methods of artificial ...[Objectives] This study was conducted to study early reproduction techniques of yellow catfish(Pelteobagrus fulvidraco) in Jianghan Plain. [Methods] Parents of P. fulvidraco were cultured by the methods of artificial temperature control and nutrition enhancement. [Results] After culture, the body weight, gonad weight, maturity coefficient and egg diameter of P. fulvidraco increased gradually. Up to April 30, the gonad weight of the female parents of P. fulvidraco cultured in greenhouses was significantly higher than that of the parents under natural conditions(P<0.05), 54% higher than that of the parents naturally cultured at the same period;the maturity coefficient of the parents cultured under strengthened conditions was also significantly higher than that of the parents under natural conditions at the same period(P<0.05);and the ovaries of the strengthened parents were orange yellow and full of eggs, and the number of eggs per fish was relatively high. In early May, the parents cultured under strengthened conditions were induced to spawn artificially. The average induced spawning rate and fertilization rate reached 86.7% and 71.6%, respectively, reaching the respective normal level. The gonad maturity of P. fulvidraco cultured under strengthened conditions was 15 d earlier than that under natural conditions, resulting in mass production of early-propagated larvae of P. fulvidraco. [Conclusions] In Jianghan plain area, artificial propagation can be achieved in early May by means of artificial temperature control and strengthened culture, which is 20 d ahead of natural conditions.展开更多
This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile...This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish(Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets(42%protein and 9% lipid) were formulated to contain graded levels of arginine(2.44%, 2.64%, 2.81%, 3.01% and3.23% of diet), by supplementing L-Arginine HCI. Seven hundred juvenile yellow catfish with an initial average body weight of 1.13 ± 0.02 g were randomly divided into 5 groups with 4 replicates of 35 fish each and each group was fed one of the diets. After 56 d feeding, fish were exposed to 100 mg/L of ammonia-nitrogen for 72 h. The results showed that weight gain(WG) and specific growth rate(SGR) in2.64% and 2.81% groups were significantly higher than those in 3.23% group(P < 0.05). The feed conversation ratio(FCR) in 2,64%, 2,81% and 3.01% groups was significantly decreased when compared with3,23% group. The protein efficiency ratio(PER) in 2.64% group was significantly higher than that in 2.44%and 3.23% groups(P < 0.05). The condition factor(CF) of fish was significantly higher in 2.81% group than that in 2,44% group(P < 0.05). Dietary arginine levels had no significant effect on hepatosomatic index(HSI), viscerosomatic index(VSI), and whole-body dry matter, crude protein, crude lipid, ash contents, as well as serum total protein(TP), triglyceride(TG), glucose(GLU), urea nitrogen(UN) contents and aspartate aminotransferase(AST), alanine aminotransferase(ALT) activities(P> 0.05). After the fish were challenged to ammonia-nitrogen for 72 h, their cumulative mortality rate in 2.81% group was significantly lower than that in 2.44% group(P < 0.05). The results suggested that dietary arginine level at 2.81%could optimize anti-ammonia-nitrogen stress ability of juvenile yellow catfish and a level of 3.23%arginine seemed to depress the growth performance of fish and decreased their tolerance to the ammonia-nitrogen stress under current study. A quadratic regression analysis based on WG indicated that the optimal dietary arginine requirement of juvenile yellow catfish was estimated to be 2.74% of the diet(6.45% of dietary protein) under current culture conditions.展开更多
In this study,three members of the Bmp family were cloned and characterized in yellow catfish Pelteobagrus fulvidraco,including Bmp2a,Bmp4 and Bmp9.The predicted amino acid sequences of P.fulvidraco Bmp2a,Bmp4 and Bmp...In this study,three members of the Bmp family were cloned and characterized in yellow catfish Pelteobagrus fulvidraco,including Bmp2a,Bmp4 and Bmp9.The predicted amino acid sequences of P.fulvidraco Bmp2a,Bmp4 and Bmp9 showed the characteristic domains of the Bmp family,including an N-terminal signal peptide,Arg-X-XArg site,TGF-β family signature and seven conserved cysteines,indicating that function is likely to have been conserved during evolution.mRNAs of the three Bmp genes had a variable level of expression in tissues.Compared to the control diet,a high fat diet tended to down-regulate the mRNA expression of Bmp2a,Bmp4 and Bmp9 in mesenteric fat,liver and ovary,while it tended to up-regulate their mRNA levels in muscle and kidney.The responses to dietary lipid status and the potential role in lipid metabolism have not previously been reported and reinforces the idea of their multiple functions.Our findings provide the first data about the potential role of the Bmp family in lipid metabolism in teleost.展开更多
文摘Over the past five years, an epidemic disease broke out in Pelteobagrus fulvidraco ponds of Zhejiang Province. The diseased fish mainly exhibits head splitting and surface bleeding; dissection results reveal hepatonephromegaly and abdominal bleeding. A bacterial strain HSY201301 was isolated from the liver tissue of P. fulvidraco with typical symptoms. Artificial infection experiment confirmed that the isolated strain had a strong virulence to healthy P. fidvidraco, leading to similar symptoms to naturally infected P. fulvidraco. The isolated strain was identified as an Edwardsiella tarda strain according to conventional morphological, physiological, biochemical characteristics and 16S rRNA gene sequence. Results of drug susceptibility test indicated that the isolated strain was sensitive to cipro- floxacin, doxitard, penicillin, doxycycline, and rocephin. This study laid solid foundation for effective prevention and control of E. tarda.
基金Supported by Science Project of Heilongjiang Province(GC03B510)
文摘Androgenesis was the especial zoogamy that the germ plasma of offspring was from the agnate. In this study the eggs of Yellow catfish （Pelteobagrus fulvidraco） were irradiated by UV suspending in the synthetic ovarian fluid （OF）, and the total dosage of UV irradiation was 220 mJ·cm^-2. Diploid could be induced by heat shock （40℃, 2 min, 3 min） with different time period after fertilization （15-37 min）. The result showed that heat shock with 2 min was better than 3 min; there were two apices of induction in 17-21 min and 27-31 min after fertilization. The highest hatching rate was 3.30% at 29 min after fertilization, and the difference between two apices of induction was unobvious.
基金Supported by The Technological Innovation Special Project of Hubei Province(2018ABA104)
文摘[Objectives] This study was conducted to study early reproduction techniques of yellow catfish(Pelteobagrus fulvidraco) in Jianghan Plain. [Methods] Parents of P. fulvidraco were cultured by the methods of artificial temperature control and nutrition enhancement. [Results] After culture, the body weight, gonad weight, maturity coefficient and egg diameter of P. fulvidraco increased gradually. Up to April 30, the gonad weight of the female parents of P. fulvidraco cultured in greenhouses was significantly higher than that of the parents under natural conditions(P<0.05), 54% higher than that of the parents naturally cultured at the same period;the maturity coefficient of the parents cultured under strengthened conditions was also significantly higher than that of the parents under natural conditions at the same period(P<0.05);and the ovaries of the strengthened parents were orange yellow and full of eggs, and the number of eggs per fish was relatively high. In early May, the parents cultured under strengthened conditions were induced to spawn artificially. The average induced spawning rate and fertilization rate reached 86.7% and 71.6%, respectively, reaching the respective normal level. The gonad maturity of P. fulvidraco cultured under strengthened conditions was 15 d earlier than that under natural conditions, resulting in mass production of early-propagated larvae of P. fulvidraco. [Conclusions] In Jianghan plain area, artificial propagation can be achieved in early May by means of artificial temperature control and strengthened culture, which is 20 d ahead of natural conditions.
基金supported by the National Natural Science Foundation of China (31402307)the construction of public service platform for the evaluation of the value of aquatic feed and feed additives in Guangdong Province(2015A040404033)
文摘This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish(Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets(42%protein and 9% lipid) were formulated to contain graded levels of arginine(2.44%, 2.64%, 2.81%, 3.01% and3.23% of diet), by supplementing L-Arginine HCI. Seven hundred juvenile yellow catfish with an initial average body weight of 1.13 ± 0.02 g were randomly divided into 5 groups with 4 replicates of 35 fish each and each group was fed one of the diets. After 56 d feeding, fish were exposed to 100 mg/L of ammonia-nitrogen for 72 h. The results showed that weight gain(WG) and specific growth rate(SGR) in2.64% and 2.81% groups were significantly higher than those in 3.23% group(P < 0.05). The feed conversation ratio(FCR) in 2,64%, 2,81% and 3.01% groups was significantly decreased when compared with3,23% group. The protein efficiency ratio(PER) in 2.64% group was significantly higher than that in 2.44%and 3.23% groups(P < 0.05). The condition factor(CF) of fish was significantly higher in 2.81% group than that in 2,44% group(P < 0.05). Dietary arginine levels had no significant effect on hepatosomatic index(HSI), viscerosomatic index(VSI), and whole-body dry matter, crude protein, crude lipid, ash contents, as well as serum total protein(TP), triglyceride(TG), glucose(GLU), urea nitrogen(UN) contents and aspartate aminotransferase(AST), alanine aminotransferase(ALT) activities(P> 0.05). After the fish were challenged to ammonia-nitrogen for 72 h, their cumulative mortality rate in 2.81% group was significantly lower than that in 2.44% group(P < 0.05). The results suggested that dietary arginine level at 2.81%could optimize anti-ammonia-nitrogen stress ability of juvenile yellow catfish and a level of 3.23%arginine seemed to depress the growth performance of fish and decreased their tolerance to the ammonia-nitrogen stress under current study. A quadratic regression analysis based on WG indicated that the optimal dietary arginine requirement of juvenile yellow catfish was estimated to be 2.74% of the diet(6.45% of dietary protein) under current culture conditions.
基金The study was funded by National Natural Science Foundation of China(Grant nos.:31572605,31001101)Project of Innovative Group for Excellent Young Scientists in Universities of Hubei Province from Hubei Provincial Department of Education(T201933).
文摘In this study,three members of the Bmp family were cloned and characterized in yellow catfish Pelteobagrus fulvidraco,including Bmp2a,Bmp4 and Bmp9.The predicted amino acid sequences of P.fulvidraco Bmp2a,Bmp4 and Bmp9 showed the characteristic domains of the Bmp family,including an N-terminal signal peptide,Arg-X-XArg site,TGF-β family signature and seven conserved cysteines,indicating that function is likely to have been conserved during evolution.mRNAs of the three Bmp genes had a variable level of expression in tissues.Compared to the control diet,a high fat diet tended to down-regulate the mRNA expression of Bmp2a,Bmp4 and Bmp9 in mesenteric fat,liver and ovary,while it tended to up-regulate their mRNA levels in muscle and kidney.The responses to dietary lipid status and the potential role in lipid metabolism have not previously been reported and reinforces the idea of their multiple functions.Our findings provide the first data about the potential role of the Bmp family in lipid metabolism in teleost.
