The growth characteristics of Conraua goliath (Boulenger, 1906), an endemic and endangered species in Cameroon, were evaluated in its natural habitat between October 2021 and November 2022 in order to contribute to its domestication and conservation. For this purpose, 139 specimens (55 males, 55 females, and 29 individuals of undifferentiated sex) were collected by fishermen from 3 sites (Loum, Penja, and Nlonako) in the Department of Moungo, Coastal Region of Cameroon. The frogs were measured, and their growth parameters were determined after dissection and macroscopic and microscopic observations. The maximum size observed is 33.5 cm (SVL) and 2529 g body weight (BW), and the minimum size is 5.3 cm (SVL) and 12 g body weight (BW). This species is more abundant in the rainy season, in frogs between 18 and 24 cm, and has a Caucasian and uni-modal size structure. Independent of sex and season, this species has a significant and high regression coefficient between length, weight, and isometric growth pattern. However, this growth varies according to sex. It ranges from isometric in males (b = 2.82) and undifferentiated sexes (b = 2.85) to negative allometry in females (b = 2.21). The condition factor K ranges from 3.28 to 14.24 (mean: 7.80 ± 1.95) and fluctuates according to the sex and size of the frog. According to our results, this species has a large size and a high growth rate and could therefore be an excellent candidate for domestication to ensure its conservation. However, studies on reproductive characteristics are needed to complete this work. Show less

The present study aimed to provide baseline information of fish culture status (obstacles) of Omdurman, Khartoum and Khartoum north in the Khartoum state in Sudan due to there is little or lack of information in this field. 30 owners of farm were questioned from Omdurman, Khartoum and Khartoum north, 10 farms for each location; Descriptive analysis was done for analyzing the raw data of the study by using Excel Microsoft Software 2007. Social data showed that male farm owners group was dominant in third sites 100%. Age groups of fishermen ranged between 20 to 60 years; where age group 31- 40 Khartoum north, age group 41- 50 was dominant in O mdurman and age group 51-60 year was dominant in Khartoum. Six educational categories were recorded where University education was dominant in the three locations 50%, 50% and 70% respectively; whereas, postgraduate was the second in the tow location: O mdurman and Khartoum 20% and the secondary education were the third in Khartoum 30%. all farm owners were married 100% in three sites; As regards to the farm owners other activities results showed that most of them were practicing other activities (farmers, business owner, officers and workers). Category of farmer was dominant 90% secondly business owner and officer 70% and 50% respectively. Data showed that the problems (Varanus niloticus, birds, marketing, fees and thefts) was dominant in three locations had the highest percentage 90%, 80%, 60%, 30% and 10% respectively. and according to production cost in three locations arranged: (feeds, workers, fingerlings, water and technical supervision) 50, and 70% and 40%, 50% and 70% and 30%, 40% and 50% and 10, 20 and 40% and 10, 20 and 30% respectively. Category of feeds dominant followed by workers and fingerlings, the best Method to obtain of information, the results showed that Bulletins was dominant in three sites 80%, 30% and 90%; whereas, field visits in three location was the second 60%, 90% and 0%, Radio programs in three location was the third 60%, 10% and 60% and the lowest percentage; Seminars and television 40%, 50% and 40%, and 30%, 0% and 0%. For the best location to obtain information results revealed that the General Director of Fisheries Ministry of Agriculture, Animal Resources and Irrigation - Khartoum State was dominant in the three locations 90%, 80% and 90%, whereas, Universities in three location was the second 40%, 20% and 0%, and the lowest percentage Central Research of fisheries 40%, 0% and 0%, and Internet 10%, 20% and30%. Also result showed most of the farm owners in three sites all them need to training courses in deferent programmers (Fish extinction, Fish feeding, Fish production and Fish marketing) according to this percentages 60%, 30% and 50%, and 30%, 10% and 50%, and 10%, 10% and 30%, and 10%, 0% and 20% respectively. Show less

This study was conducted to evaluate the effect of socked pigeon pea seed meal on Growth and Food Utilization Efficiency of Nile tilapia (Oreochromis niloticus) fingerlings. 120 fish the weight and length average (3.4±0.04g and 3.2±0.00cm) were randomly distributed in 12 plastic Tanks (Aquarium) 36L according to the complete randomization, allocated to a represent four treatments (T0, T1, T2, and T3) of Nile tilapia (Oreochromis niloticus) fingerlings. four feeds were prepared in pellet form which consisted of 0%, 25%, 50% and 75% pigeon pea seed meal as replacement of fish meal. All diets contents 30% protein. Nile tilapia (Oreochromis niloticus) fingerlings were fed at the rate of 5% of their body weight. The result showed significant variation (P < 0.05) in final body weight, weight gain (WG), daily weight growth (DWG), Specific Growth Rate (SGR), and Food Conversion Ratio (FCR) among treatments. But, high SGR in T0 (control) and the best FCR were obtained at T 0% pigeon pea seed meal. Over all, best growth performance was observed in fish fed diet T1 (25%). The best performing fish’s final weight, DWG, SGR and FCR were 9.46±0.33g, 0.13±0.01g/day, 2.93±0.73% /day and 1.49±0.30 respectively. On the other hand, there was high significant variation (P < 0.05) in survival rate were obtained at T2 (50%). this study recommend that a diet containing 25% Pigeon pea seed meal for juvenile Nile tilapia is optimum in terms of growth performance and profitability, and does not impact water quality and plankton abundance in plastic Tanks (Aquarium) culture system. Show less

The effects of rearing density on large juvenile bluegill Lepomis macrochirus growth in recirculating aquaculture systems are relatively unknown. This 63-day study evaluated three initial densities: low (6 kg/m3), intermediate (12 kg/m3), and high (18 kg/m3). Final densities were low (8.1 kg/m3), intermediate (16.6 kg/m3), and high (20.9 kg/m3). At the end of the study, fish reared in the low-density tanks had a mean (SD) weight of 95.99 (7.49) g, which was significantly heavier than the 75.70 (4.28) g mean weight of fish in the high-density tanks. At 86.23 (7.63) g, the weight of individual fish in the intermediate-density treatment was not significantly different from either the low or high-density treatments. Specific growth rate was also significantly greater in the low-density treatment than in the high-density treatment. Individual fish total lengths were not significantly different among densities, with mean (SD) values of 155 (4) mm, 152 (4) mm, and 148 (2) mm for the low, intermediate, and high-density treatments, respectively. Similar to fish weight, condition factor was significantly greater in the low-density treatment than in the high-density treatment, while condition factor in the intermediate-density treatment did not differ significantly from the other treatments. Tank gain, percent gain, and feed conversion ratio did not differ significantly among treatments. These results indicate that of the three bluegill rearing densities evaluated in this study, the intermediate initial density of 12 kg/m3 appeared to produce the best balance of individual fish growth and total biomass production. Show less