ABSTRACT
Background: Human activities adversely affect the distribution and diversity of zooplankton. They are diverse group of organisms with little or no locomotive ability and quickly respond to changes in their environment. This research was aimed at providing updated information on the distribution and seasonal variation of zooplankton in Great Kwa River. Materials and Methods: Two sampling stations (S1- Obufa Esuk and S2- Esuk Atu) were mapped along the river bank, samples were collected using plankton net of 55祄 mesh size and preserved in 4% formalin. Species were identified using taxonomic keys. Data were analyzed using ecological indices. Results: The results revealed 12 taxa; belonging to 38 species. Tintinnida, Protozoa, Cladocera, Copepoda were 23.1%, 18.5%, 15.4% and 13.3% respectively. The lowest taxonomic groups were Diptera, Foraminitera, Atenatadata and Trichoptera having 1.85% for each order. The highest species was recorded in S2 having 31 species. In both Stations Ascampbelliella acuta was dominance over other species. Shannon-Weiner index (H) were 2.997 and 2.40 in S2 and S1 respectively. The evenness index were 0.576 and 0.547 for S1 and S2 respectively. Margalef,s diversity index were 8.171 and 4.111 for Esuk Atu-S2 and Obufa Esuk-S1 respectively. Zooplankton species were abundant in wet season than dry season. Conclusion: This present study provide updated information on the zooplankton distribution, diversity and seasonal variations of the Great Kwa River. The high dominance of Tintinnida in this study indicates a natural linkage between nano-planktons and macro-planktons in the food webs of the river.
ABSTRACT
This study was designed to evaluate the effects of pawpaw (Carica papaya) seeds, hibiscus plant (Hibiscus rosa-sinensis) leaves andsweet potato (Ipomoea batatas) leavesextractson sperm quality (sperm motility, sperm density, semen volume) and weight of testes of male Clarias gariepinus.One hundred and twenty (120) juveniles of C. gariepinuswere collected from the University of Calabar fish farm. The 120 fish were randomly divided into 12 experimental tanks measuring 80x80x80cm (L x W x H), with three tanks for each treatment, using a completely randomized design (CRD). Three grams (3g) of each test plant were incorporated into 1kg of Coppens feed (3g/kg) and reformulated into four experimental diets; Treatment A-Control, B-Pawpaw seed meal (PSM), C-Hibiscus leaf meal (HLM) and D-sweet potato leaf meal (SPLM). The experiment was done in three replications. The fish were fed twice daily for 6 months. Data obtained were analyzed using a one way analysis of variance (ANOVA). Results showed that fish fed with HLM had significantly (p =.05) higher testicular weight when compared with the control and other test plants. Moreover, sperm volume and density significantly (p =.05) reduced in fish samples treated with PSM and SPLM when compared with the control and fish fed with HLM. The highest mean sperm volume and density were obtained in fish samples fed with HLM. No significant difference was observed in the sperm motility of the fish in all the treatment groups. Conclusively, this study reveals the pro-fertility potential ofH. rosa-sinensisin maleC. gariepinuswhile C. papaya and I. batatas possess anti-fertility properties. Therefore, HLM can be utilized as feed additive to minimize the dependence on synthetic drugs as fertility enhancing agents.
ABSTRACT
This study investigated the reproductive performance of pawpaw (Carica papaya) seeds, hibiscus plant (Hibiscus rosa-sinensis) leaves and sweet potato (Ipomoea batatas) leaves on some reproductive parameters (ovary weight, mean egg diameter and egg fecundity) in female African catfish (Clarias gariepinus). One hundred and twenty (120) juveniles of C. gariepinus were collected from the University of Calabar fish farm. The 120 fish were randomly divided into 12 experimental tanks measuring 80x80x80 cm (L x W x H) using a completely randomized design (CRD). Three grams (3 g) of each test plant were incorporated into 1 kg of Coppens feed (3 g/kg) and reformulated into four experimental diets; Treatment A- Control, B- pawpaw seed meal, C- Hibiscus leaf meal and D- sweet potato leaf meal. The experiment was done in three replications. The fish were fed twice daily for 6 months. Data obtained were analyzed using a one way analysis of variance (ANOVA). Results obtained revealed that the different test substances significantly (p<0.05) negatively affected the different reproductive parameters studied. The ovary weight, gonadosomatic index (GSI), egg diameter, fecundity as well as total weight significantly (p<0.05) decreased in all the treated fish when compared with that of the control. Pawpaw seed meal (PSM) had the highest effect on the reproductive parameters of the fish studied (ovary weight, GSI, fecundity and egg diameter values of 14.89±5.51, 0.82±0.30, 19371±51.84 and 0.63±0.07, respectively) when compared to the other test plants. The findings of this study suggest that C. papaya seeds, hibiscus leaves and sweet potato leaves have the potential to impair reproductive performance in female African catfish. Therefore, holistic measures should always be taken when using these plants considering the effect it could exert on other aquatic inhabitants and systems.