Using multi-molecular marker technologies and based on morphological criteria, the genetic relationship between Epinepheelus malabaricus and E, coioides was examined in the hope of resolving the long-standing issue of...Using multi-molecular marker technologies and based on morphological criteria, the genetic relationship between Epinepheelus malabaricus and E, coioides was examined in the hope of resolving the long-standing issue of identifying these two species. Results showed that： （ 1 ） E. coioides and E. malabaricus should be identified as two species, the consistency of mitochondrial DNA cytochrome b gene sequence between E. malabaricus and E. coioides is 94.4%, and the genetic similarity by AFLP was 0.753 9 ; （2） Hybridization exists between E. malabaricus and E. coioides, the specific RAPD and AFLP fragments are found to be useful in the identification of these two species, and the genetic properties （both with exterior and inheritance） of hybrid is significantly biased to the male parents ; and （3） AFLP was a potentially powerful tool in constructing the genetic linkage map for these two groupers.展开更多
Objective:To examine the effect of isopod parasite Catoessa boscii(C.boscii)on Carangoides malabaricus(C.malabaricus).Methods:The host fish C.malabaricus infested by C.boscii were collected directly from the trawlers ...Objective:To examine the effect of isopod parasite Catoessa boscii(C.boscii)on Carangoides malabaricus(C.malabaricus).Methods:The host fish C.malabaricus infested by C.boscii were collected directly from the trawlers landed at Parangipettai coast during December 2008 to November2009.Data regarding the total length,width,weight and sex of the host fish were recorded.Effect of infestation on C.malabaricus,the length and weight data were analysed and host specificity of isopods was also examined.Results:During the sampling period,585 C.malabaricus were examined.Among them,218 specimens were found to carry 243 parasites.Three pairs of isopods(one male with one female)were recorded from the host fish and each pair was attached to the tongue in the buccal cavity of the host.Another pair was also found where the male and male,female and female isopod had settled on the tongue in the buccal cavity.Gross lesions observed in the buccal cavity of infested fish showed small pin-holes in the tongue region,through which dactyls of pereopod's penetrating claws dig into the host tissues.The maximum weight loss was reported in females(5.43%)than in males(3.75%)of C.malabaricus.Due to infestation of different isopod parasites in both male and female fish,the effects on the length-weight relationship of C.malabaricus were compared.The rate of increased growth in weight in uninfested female fish was found to be higher than that of the infested.The weight gain is faster in uninfested fish than in the infested fish.Conclusions:From the above mentioned observations,it is clear that the worst of fish on account of the infestation of isopods are the C.malabaricus succumbed to the attack of isopod parasites.Although,the infestation did not cause immediate death,it had affected the normal growth of the host fish.展开更多
Objective:To study the prevalence of philometrid nematode,Philometra spp.infected in the ovaries of Epinephelus malabaricus(E.malabaricus)from southeast coast of India.Methods:Totally 4801 fishes were collected from M...Objective:To study the prevalence of philometrid nematode,Philometra spp.infected in the ovaries of Epinephelus malabaricus(E.malabaricus)from southeast coast of India.Methods:Totally 4801 fishes were collected from Mandabam,Tuticorin and Kanyakumari.The normal and infected ovaries were carefully removed from dissected fishes and the prevalence of nematode infection for each fish was examined.Then the nematode were carefully removed and washed in a 0.6%saline solution and fixed in 70%ethanol.Representative nematodes were cleaned with glycerin and fixed in a solution of 95%glacial acitic acid and 5%formalin for identification under light microscopy.Results:Of which 16.8%,16.2%and 14.7%parasitic prevalence was observed from Mandabam,Tuticorin and Kanyakumari respectively.The intensity of parasitic worms per fish varied from 1 to 8 with an average of 6.33±0.84.Nematode length varies from 7-22 mm with in average of(18.70±4.57)mm.The average length and weight of E.malabaricus were(332.950±77.792)mm and(513.30±169.46)g respectively.Conclusions:It can be assumed that females of this nematode are unable to attain gravidity in this host species,and consequently,E.malabaricus does not serve as the true definitive host of Philometra spp.Prevalence of infection and intensity of the nematode are highly effected by sucking blood,causing atrophy of developing ova in the ovary,fibrosis of ovarian tissue,increasing granulocytes and haemorrhages,and thus negatively affecting the reproduction of some species of E.malabaricus.展开更多
基金This study was supported by the National Natural Science Foundation of China under contract Nos 40306023 and 40576064the Important Program of Science and Technology of Fujian Province in China under contract No.2004NZ03.
文摘Using multi-molecular marker technologies and based on morphological criteria, the genetic relationship between Epinepheelus malabaricus and E, coioides was examined in the hope of resolving the long-standing issue of identifying these two species. Results showed that： （ 1 ） E. coioides and E. malabaricus should be identified as two species, the consistency of mitochondrial DNA cytochrome b gene sequence between E. malabaricus and E. coioides is 94.4%, and the genetic similarity by AFLP was 0.753 9 ; （2） Hybridization exists between E. malabaricus and E. coioides, the specific RAPD and AFLP fragments are found to be useful in the identification of these two species, and the genetic properties （both with exterior and inheritance） of hybrid is significantly biased to the male parents ; and （3） AFLP was a potentially powerful tool in constructing the genetic linkage map for these two groupers.
基金Financially supported by Department of Science and Technology(Grant No:SR/FF/LS-088/2007)Ministry of Environment&Forest,Government of India(Grant No:22-18/2008-CS-I)
文摘Objective:To examine the effect of isopod parasite Catoessa boscii(C.boscii)on Carangoides malabaricus(C.malabaricus).Methods:The host fish C.malabaricus infested by C.boscii were collected directly from the trawlers landed at Parangipettai coast during December 2008 to November2009.Data regarding the total length,width,weight and sex of the host fish were recorded.Effect of infestation on C.malabaricus,the length and weight data were analysed and host specificity of isopods was also examined.Results:During the sampling period,585 C.malabaricus were examined.Among them,218 specimens were found to carry 243 parasites.Three pairs of isopods(one male with one female)were recorded from the host fish and each pair was attached to the tongue in the buccal cavity of the host.Another pair was also found where the male and male,female and female isopod had settled on the tongue in the buccal cavity.Gross lesions observed in the buccal cavity of infested fish showed small pin-holes in the tongue region,through which dactyls of pereopod's penetrating claws dig into the host tissues.The maximum weight loss was reported in females(5.43%)than in males(3.75%)of C.malabaricus.Due to infestation of different isopod parasites in both male and female fish,the effects on the length-weight relationship of C.malabaricus were compared.The rate of increased growth in weight in uninfested female fish was found to be higher than that of the infested.The weight gain is faster in uninfested fish than in the infested fish.Conclusions:From the above mentioned observations,it is clear that the worst of fish on account of the infestation of isopods are the C.malabaricus succumbed to the attack of isopod parasites.Although,the infestation did not cause immediate death,it had affected the normal growth of the host fish.
基金Supported by Department of Biotechnology,Government of India,New Delhi(Grant No.BT/PR14992/SPD/11/1332/2010).
文摘Objective:To study the prevalence of philometrid nematode,Philometra spp.infected in the ovaries of Epinephelus malabaricus(E.malabaricus)from southeast coast of India.Methods:Totally 4801 fishes were collected from Mandabam,Tuticorin and Kanyakumari.The normal and infected ovaries were carefully removed from dissected fishes and the prevalence of nematode infection for each fish was examined.Then the nematode were carefully removed and washed in a 0.6%saline solution and fixed in 70%ethanol.Representative nematodes were cleaned with glycerin and fixed in a solution of 95%glacial acitic acid and 5%formalin for identification under light microscopy.Results:Of which 16.8%,16.2%and 14.7%parasitic prevalence was observed from Mandabam,Tuticorin and Kanyakumari respectively.The intensity of parasitic worms per fish varied from 1 to 8 with an average of 6.33±0.84.Nematode length varies from 7-22 mm with in average of(18.70±4.57)mm.The average length and weight of E.malabaricus were(332.950±77.792)mm and(513.30±169.46)g respectively.Conclusions:It can be assumed that females of this nematode are unable to attain gravidity in this host species,and consequently,E.malabaricus does not serve as the true definitive host of Philometra spp.Prevalence of infection and intensity of the nematode are highly effected by sucking blood,causing atrophy of developing ova in the ovary,fibrosis of ovarian tissue,increasing granulocytes and haemorrhages,and thus negatively affecting the reproduction of some species of E.malabaricus.
