Phenotypic characterisation in interspecific and intergeneric hybrids of the clariid catfishesHeterobranchus longifilis,Clarias gariepinusandClarias anguillarisin Nigeria
Abstract:Thirty-nine morphometric and five meristic comparisons were carried out on 12-month-old interspecific and intergeneric hybrids of the African clariid catfishes Heterobranchus longifilis, Clarias gariepinus and Clarias anguillaris from experimental earthen ponds in Nigeria. Canonical discriminant analysis accounted for 89.4% of the variations, with eigenvalues of 151.69 and 9.06, respectively, the highest loading in the two axes coming from only 12 variables. A re-analysis based on those 12 variables revealed f… Show more
“… 27 and Akinwande et al . 2 , had earlier concluded that the display of intermediate phenotypic characteristics in the ♀ C. gariepinus × ♂ Heterobranchus longifilis (V.) hybrid was an indication of true hybridization. Hence, it is thought that they resulted from the fusion of the genetic material of both parents.…”
Section: Resultsmentioning
confidence: 99%
“… Figure 2 Morphological landmarks points for ( A ) typical pure Clarias gariepinus /Clarias-like Clariothalmus ( B ) Panga-like Clariothalmus ( C ) typical Pangapinus/ Pangasianodon hypophthalmus . Landmark points are; Snout 1 , origin of dorsal fin 2 , posterior end of the dorsal fin 3 , dorsal attachment of the caudal fin to the tail 4 , ventral attachment of the caudal fin to the tail 5 , posterior end of the anal fin 6 , origin of the anal fin 7 , origin of the pelvic fin 8 , origin of the pectoral fin 9 and the posterior point of the eye 10 . …”
Section: Methodsmentioning
confidence: 99%
“…It is one of the biotechnological breeding tools used to develop new genetic stocks of fish for aquaculture/fisheries industries and a viable alternative to selective breeding when there is little additive genetic variation in the desired traits of pure stocks to be exploited 1 . However, successful genetic improvement through hybridization and other biotechnology tools requires proper identification and classification of species 2 . Hybrid identification is a problem linked to natural resources management because fertile hybrids could interbreed with pure species leading to genetic introgression.…”
Twenty-five traditional and thirty-four geometric morphometric comparisons were carried out on pure and reciprocal crosses of Pangasianodon hypophthalmus (Sauvage, 1878) and Clarias gariepinus (Burchell, 1822). Thirty fish samples each of the C. gariepinus (CH), P. hypophthalmus (PH), Pangapinus (♀PH × ♂CG) and the two distinct morphotypes of the Clariothalmus (♀CG × ♂PH) (Clarias-like and Panga-like) between the ages of four and six months were used for this study. Phenotypically, the Clarias-like Clariothalmus and the Pangapinus progenies were indistinguishable from their maternal parents while the Panga-like Clariothalmus was a phenotypic intermediary of the putative parents but looks more closely to the paternal parent. Hence, both univariate proportion and multivariate analysis of the collected data successfully separated the different fishes into three multivariate spaces. The analysis of the dendrogram with complete linkage and Euclidean distance further showed the close relationship of the isolated Panga-like Clariothalmus progenies to the paternal parent, however, Clarias-like Clariothalmus and the Pangapinus were completely intermingled with their maternal parents. The most important index of discrimination of these fishes into different multivariate spaces was the fin characteristic which showed 100% exclusive ranges for the individual groups in many cases.
“… 27 and Akinwande et al . 2 , had earlier concluded that the display of intermediate phenotypic characteristics in the ♀ C. gariepinus × ♂ Heterobranchus longifilis (V.) hybrid was an indication of true hybridization. Hence, it is thought that they resulted from the fusion of the genetic material of both parents.…”
Section: Resultsmentioning
confidence: 99%
“… Figure 2 Morphological landmarks points for ( A ) typical pure Clarias gariepinus /Clarias-like Clariothalmus ( B ) Panga-like Clariothalmus ( C ) typical Pangapinus/ Pangasianodon hypophthalmus . Landmark points are; Snout 1 , origin of dorsal fin 2 , posterior end of the dorsal fin 3 , dorsal attachment of the caudal fin to the tail 4 , ventral attachment of the caudal fin to the tail 5 , posterior end of the anal fin 6 , origin of the anal fin 7 , origin of the pelvic fin 8 , origin of the pectoral fin 9 and the posterior point of the eye 10 . …”
Section: Methodsmentioning
confidence: 99%
“…It is one of the biotechnological breeding tools used to develop new genetic stocks of fish for aquaculture/fisheries industries and a viable alternative to selective breeding when there is little additive genetic variation in the desired traits of pure stocks to be exploited 1 . However, successful genetic improvement through hybridization and other biotechnology tools requires proper identification and classification of species 2 . Hybrid identification is a problem linked to natural resources management because fertile hybrids could interbreed with pure species leading to genetic introgression.…”
Twenty-five traditional and thirty-four geometric morphometric comparisons were carried out on pure and reciprocal crosses of Pangasianodon hypophthalmus (Sauvage, 1878) and Clarias gariepinus (Burchell, 1822). Thirty fish samples each of the C. gariepinus (CH), P. hypophthalmus (PH), Pangapinus (♀PH × ♂CG) and the two distinct morphotypes of the Clariothalmus (♀CG × ♂PH) (Clarias-like and Panga-like) between the ages of four and six months were used for this study. Phenotypically, the Clarias-like Clariothalmus and the Pangapinus progenies were indistinguishable from their maternal parents while the Panga-like Clariothalmus was a phenotypic intermediary of the putative parents but looks more closely to the paternal parent. Hence, both univariate proportion and multivariate analysis of the collected data successfully separated the different fishes into three multivariate spaces. The analysis of the dendrogram with complete linkage and Euclidean distance further showed the close relationship of the isolated Panga-like Clariothalmus progenies to the paternal parent, however, Clarias-like Clariothalmus and the Pangapinus were completely intermingled with their maternal parents. The most important index of discrimination of these fishes into different multivariate spaces was the fin characteristic which showed 100% exclusive ranges for the individual groups in many cases.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
