The study of ecology and parasites of herpetological animals (amphibians and reptiles) in Obafemi Awolowo University,Ile-Ife,Osun State.
This study investigated the abundance and ecology of amphibians (Anura) and reptiles (Agamidae) in ObafemiAwolowo University, Ile-Ife, Osun State, Nigeria. It also assessed the prevalence and intensity of ectoparasites and endoparasites of the animals with a view to determining the patterns of parasitic infection among the herptiles in the study area. Amphibians and reptiles were monitored in seven ecologically divergent locations purposively selected within the campus of ObafemiAwolowo University, Ile-Ife. Each location was monitored once every month for nine months (February – November, 2015) for presence and number of amphibians and reptiles. Each herptile encountered was captured, properly labelled and taken to the laboratory for identification and parasitological examination. In the laboratory, each animal was anesthetized with chloroform, weighed (using Scout pro Top loading balance Model Scout ProSPU202)) and the snout-vent length (SVL) measured using a meter rule. The animal was then identified using standard keys and photographed. The body was thoroughly examined for ectoparasites section by section. Each animal was then dissected longitudinally and the gastro-intestinal canal carefully removed and divided into sections. Each section,(oesophagus, stomach, small intestine and large intestine) was fixed separately in physiological saline for the recovery of parasites. Parasites recovered were fixed in alcohol-formal acetic acid (A.F.A) and preserved in 70% alcohol and 5% glycerol to prevent dehydration. The parasites recovered were then identified using standard keys and lucida photographs taken within 24 hours. Data were analyzed using the Chi square test, analysis of variance and correlation analyses. Out of 231 herptiles collected, 111 were reptiles and 120 were amphibians. These comprised of one species of reptile (Agama agama) and five species of amphibians (Buforegularis, Hoplobatrachusoccipitalis, Hylaranaalbolabris, Ptychadenaaequiplicata and Ptychadenaoxyrhynchus). The highest number of reptiles (46) was collected from Fajuyi Hall and the lowest (5) from Kajola Village. The corresponding values for the amphibians were 43 at the Agric Research Farm and 12 at Awolowo Hall, respectively. Ten parasite species were isolated. These included Strongylurisbrevicaudata, Parapharyngodon sp. I, Parapharyngodon sp. II, Oochoristicatruncata, Mesocoeliummonas and an unidentified nematode were collected from the reptile and Thelandros sp. I, II, III, IV and Mesocoeliummonaswere isolated from the amphibians. All the parasites were endoparasites and no ectoparasites were recorded. All the reptiles collected were infected with one parasite or the other, thus, prevalence of infection amongst them was 100%. Conversely, only 68.3% of the 120 amphibians were infected. The large intestine harbored most of the parasites (72.6%) while the stomach harbored the least number (1.9%). The infection rate among the sections was significantly different (p< 0.05). Prevalence of infection amongst the amphibians was highest at Agricultural Research Farm (60.9%) and least at the Library area (18.2%). These patterns were significantly different (p< 0.05). Strongylurisbrevicaudata was the most frequently observed helminth with a prevalence of 95.5% while Thelandrosspecies IV was the least prevalent (2.7%). The herptiles harbored multiple infections of two to four helminth species. Double infection was the most common mixed infection (41.4% reptiles and 35.4% in amphibians). The study concluded that the prevalence of parasitic infection among herptiles in the ObafemiAwolowo University which was high raised an important public health concern.