World Science and Research PublishingGlobal Journal of Animal Scientific Research2345-43773120141023Intraspecific-Relationship between Freshwater Carp Fish (Cypriniformes: Cyprinidae) Length-Weight and Prevalence of Ectoparasites120120ENFarzanaPerveenDepartment of Zoology,Shaheed Benazir Bhutto University (SBBU),Main Campus, Sheringal,Khyber Pakhtunkhwa. farzana_san@hotmail.comHanifUllah201409252014102320141022During the present study, a total of 1800 fish of 6 species including indigenous and exotic fresh water carp (Cypriniformes: Cyprinidae) were examined for determining intraspecific-relationship between their length-weight and prevalence of ectoparasites at Charbanda Carp Fish Hatchery (CCFH), Mardan, Khyber Pakhtunkhwa, Pakistan. The prevalence of 3 ectoparasites were recovered viz.: the anchor worm, Lernaea cyprinacea Linnaeus (Crustacea: Copepoda) (14.4%); carp lice, Argulus foliaceus Linnaeus (Crustacea: Maxillopoda) (3.6%) and salmon fluke, Gyrodactylus sp. Malmberg (Platyhelminthes: Monogenea) (2%). The relationship between body-length and ectoparasites revealed maximum infestation was 18.3% on both sides by L. cyprinacea in length group of 12-30 cm and it was minimum 8.1% in 69<cm group. While maximum prevalence was 15.5% by A. foliaceus in 69<cm and minimum 0.6% was in 12-30 cm groups. The prevalence by Gyrodactylus sp. was maximum 0.7% in 50-68 cm group. The relationship between body-weight and ectoparasites showed that L. cyprinacea was the highest 21% in 15-500 g and the lowest 8.2% in 987<g groups, while for A. foliaceus maximum prevalence 7.2% was observed in 987<g and the prevalence by Gyrodactylus sp. was maximum 0.5% in 501-986 g group. The prevalence of L. cyprinacea was 50.2% in indigenous and 49.9% exotic carp, however, the prevalence of A. foliaceus was 54% in exotic compared with indigenous (11%), moreover, Gyrodactylus sp. was only found in indigenous carp, i.e., C. mrigala (6%). Ectoparasites, L. cyprinacea, A. foliaceus and Gyrodactylus sp. are existing in Pakistan. This paper helps in keeping the health status of carp fish with respect to observe ectoparasites