HELMINTH PARASITES OF SOME FRESHWATER FISHES
MUHAMMAD SHAFIQ AHMED, TAHIR IQBAL, AMJAD MAHMOOD, MUHAMMAD GULZARIN AND MUHAMMAD ABID Department of Zoology, University of the Punjab, Quaid-e-Azam Campus, Lahore-54590 (MSA, MA); Department of Zoology, University of Azad Jammu & Kashmir, Muzaffarabad (TI, AM, MG), Pakistan. Abstract: Forty-three freshwater fishes (Heteropneustus fossilis 11, Mystus vittatus 16 and Channa striatus 16) were collected from various freshwater ponds in the vicinity of Lahore and brought to the lab. All fishes were examined for the presence of internal helminth parasites in the digestive tract. The study revealed that all (100%) H. fossilis were infected with nematodes, Procamallanus heteropneustus, only 6 (37.5%) M. vittatus were found infected with nematodes, Rhabdochona magna and among C. striatus, 9 fish (56.25%) were infected with acanthocephalans, Pallisentis ophiocephali, 4 (25%) were infected with cestodes, Senga taunsaensis and 5 (31.25%) were infected with nematodes, R. magna. The mean intensity of infection was 14.36 in H. fossilis, 6.5 in M. vittatus and in C. striatus, 3.33 for acanthocephalans, 2.4 for nematodes and only 1.0 for cestodes per infected fish. The results indicate that the parasite intensity is quite high. It may be due to the presence of physical factors that favour the completion of life cycles of these parasites. Keywords: Freshwater fishes, fish helminth, parasite intensity, prevalence, gut parasites.
here are many freshwater ponds which are used to culture fishes in the area of Kasur near Lahore. Heteropneustus fossilis, Mystus vittatus and Channa striatus are carnivorous fishes commonly found in these small ponds receiving mainly rainwater. These ponds are managed by local people for fish raising. Fishes being very important source of protein for human are consumed as white meat. Since humans utilize these fishes, it is important that they should be healthy and free of infection. Infections which are caused by viruses, bacteria and parasites among fishes 0079-8045/07/0001-0006 $ 03.00/0 Copyright 2007, Dept. Zool., P.U., Lahore, Pakistan
M. S. AHMAD ET AL.
in natural and man made culture systems are harmful for fish health and growth. The parasitic infections are sometimes very fatal and can cause high mortalities (Ahmed, 1994) when intermediate hosts support their life cycles. Among freshwater fishes, there are 1211 species of different parasites representing 5 phyla and 11 classes of invertebrates (Bykovskaya et al., 1964). The major parasitic groups found in freshwater fishes are trematodes, cestodes, acanthocephalans and nematodes that complete their life cycles through intermediate hosts like piscivorous birds (Schmidt, 1990). The need to assess the parasitic infection arises because the fish suffering from parasitic infection or disease result into severe damage to fisheries industry. For successful prevention and elimination of such infections, it is extremely important to achieve early and correct diagnosis of the larval stages of the parasites for which fish constitute the final host.
MATERIALS AND METHODS
A sample of 43 fishes comprising 11 specimens of Heteropneustes fossilis, 16 specimens of Mystus vittatus and 16 specimens of Channa striatus, was obtained from different freshwater ponds found in the area of Kasur near Lahore. Fishes were brought in the laboratory alive in a small container and each species was maintained in glass aquaria separately. Length and weight of each fish were recorded. Fish were dissected one by one exposing their visceral organs. The stomach and the intestine were cut open lengthwise as to expose the lumen. The lumen was washed gently with distilled water in Petri plates and was observed under dissecting microscope. All the parasites recovered from the gut were preserved in 70% alcohol. They were cleaned and kept in small vials for...