Nigerian Journal of Fisheries and Aquaculture <p>The Nigerian Journal of Fisheries and Aquaculture (NIJFAQ) is an international scholarly and paired reviewed bi-monthly (May and September) Journal that publish original research papers and short communications. It is an official publication of the Department of Fisheries, University of Maiduguri, Maiduguri, Nigeria. The Journal intends to provide a forum for sharing of ideas and research findings in the area of Fisheries and Aquaculture. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. The scope of the journal include Fish Breeding and hatchery management, Fish Biology, Fish Farming Systems, Fish Gear Technology, Fish Genetics and Biotechnology, Fish Ecology, Fish Health management, Fish Diseases and Parasites Fisheries Management, Fish Nutrition, Fish Post harvest Technology, Aquatic Toxicology, Aquatic Pollution, Fisheries Economics, Fisheries Extension, Hydrobiology, Limnology, Aquaponics, Integrated Fish Farming, Climate Change in Fisheries and Aquaculture etc. All manuscripts should be written in English.</p> <p>&nbsp;</p> <p>&nbsp;</p> <p>&nbsp;</p> Department of Fisheries, Faculty of Agriculture, University of Maiduguri, Maiduguri, Nigeria. en-US Nigerian Journal of Fisheries and Aquaculture 2350-1537 <p>&nbsp;</p> <p>&nbsp;</p> Food and Feeding Habits of Three Selected Fish Species of Lower River Benue, Benue State, Nigeria <p>This study aimed to investigate the food and feeding habits of three fish species: <em>Hydrocynus forskahlii, Citharinus</em> <em>citharus</em>, and <em>Mormyrus rume</em>, caught from the Lower River Benue. Currently, there is not enough information available on the feeding habits of these fish species in the Lower River Benue.&nbsp; The study examined 189 <em>Hydrocynus</em> <em>forskahlii</em> from Abinsi, 214 from Wadata station, 372 <em>Citharinus citharus</em> from Abinsi, 366 from Wadata, and 384 and 363 <em>Mormyrus rume</em> from Abinsi and Wadata, respectively, using gill and cast nets. Specimens were collected every two weeks from fishermen in the Lower River Benue between April 2019 and March 2020. The study measured gut weight and length, performed gut content analysis using the frequency of occurrence, numerical abundance, and total point methods, identified food items, and obtained the stomach vacuity index. Results showed that <em>H. forskahlii</em> mainly feeds on worms, insect parts, and juvenile fish. <em>C. citharus</em> feeds mainly on detritus and plant materials, while M. rume feeds predominantly on detritus, plant materials, worms, and whole fish. <em>H</em>. <em>forskahlii</em> and <em>C</em>. <em>citharus</em> have higher percentages of food in their stomachs from Wadata, while M. rume had it from Abinsi. In conclusion, <em>H.</em> <em>forskahlii</em> is confirmed to be a carnivorous species, while <em>C. citharus</em> and <em>M</em>. <em>rume</em> are omnivorous species.</p> Tsevenda, C. A. Annune, P. A. P. A. Olufeagba S. O. Ataguba G. A. Copyright (c) 2024 Nigerian Journal of Fisheries and Aquaculture 2024-05-29 2024-05-29 12 1 1 15 Effect of Filleting and Peeled Undeveined Pre-Processing Methods on the Microbial Load of Frozen Nigerian Tongue Sole Fish (Cynoglossus Browni) and Brown Shrimps (Parapenaeopsis Atlantica) in a Fish Processing Plant <p>The study examined the impact of filleting and peeled undeveined pre-processing methods on the microbial load of <em>Cynoglossus browni </em>and<em> Parapenaeopsis atlantica</em> in a fish processing plant. These pre-processing steps <em>converted P. atlantica </em>and<em> C. browni</em> into ready-to-cook products, such as peeled undeveined shrimps and sole fish fillets. The study involved taking twenty samples of both <em>P. atlantica </em>and <em>C. browni</em>, before and after pre-processing, to the laboratory for standard microbiological analysis. The results showed that the total plate count and <em>Staphylococcus aureus</em> count in <em>P. atlantica</em> and <em>C. browni</em> significantly reduced after applying the peeled undeveined and filleting pre-processing methods, except for yeast and mold, which had an increase in its count. The study also found that the microbial count of <em>Staphylococcus aureus</em> in frozen Sole fish decreased from 108CFU/g to 44CFU/g in sole fillets. Notably, the pre-processing methods were most effective on <em>P. atlantica</em>, reducing the total plate count of frozen brown shrimps from 87123CFU/g to a total plate count of 1159CFU/g in peeled undeveined shrimps. However, the pre-processing method was also least effective on <em>P. atlantica</em>, with a 14.5% increase in yeast and mold of frozen brown shrimps from 821CFU/g to yeast and mold of 1186.5CFU/g in PUD shrimps. Additionally, the study found that for both species in the frozen and pre-processed states, the most probable number had less than 3.0 CFU/g. The study also revealed that <em>Escherichia coli, Salmonella</em> <em>spp, Shigella spp, </em>and<em> Vibrio parahaemolyticus</em> were not detected. Conclusively, the microbial counts were within the limit recommended by the European Commission, indicating that these products are safe for consumption.</p> Oluwajana O. P. Copyright (c) 2024 Nigerian Journal of Fisheries and Aquaculture Https:// 2024-05-29 2024-05-29 12 1 16 25 Age, Growth and Mortality of Auchenoglanis occidentalis (Valenciennes, 1840) from Lake Akata, Benue State, Nigeria <p>The examination of the age, growth, and mortality of<em> Auchenoglanis. occidentalis </em>from Lake Akata was investigated for 12 months. A total of 770 samples of <em>A. occidentalis </em>were collected from May 2022 to April 2023 from fishermen operating at Lake Akata. Estimating age and growth utilised Bhattacharya's length frequency distribution assortment method, along with the von Bertalanffy, Gulland, and Holt plot methods. The result showed that the mean standard length (cm) and weight (g) of<em> A. occidentalis </em>were 25.34±0.36 cm and 284.6±6.9 g respectively. <em>Auchenoglanis occidentalis</em> with a condition factor of 1.53± 0.02 demonstrated favorable health. Both male and female<em> A. occidentalis </em>displayed a negative allometric growth pattern. The predictive von Bertalanffy growth parameters were L∞ (46.73 cm), K (0.280), and t<sub>o</sub> (0.88 years), represented by Lt = 46.73 [1 - exp (-0.280 (t – 0.88)]. The fish population was divided into three age brackets. The growth performance index (Ф1) measured 2.79, and the total mortality (Z), calculated using Hoenig's Model I in FISAT II, was 1.434 per year. The instantaneous fishing mortality (F) was 0.781 per year, and the instantaneous natural mortality (M) was 0.651 per year, leading to an exploitation rate (E) of 0.545. This signifies an exceptionally high level of exploitation. To safeguard these species from extinction, it's necessary to implement management actions like setting limits on mesh size, restricting fishing activities, and declaring specific seasons off-limits for fishing. To promote the sustainable exploitation and management of the<em> A. occidentalis </em>fisheries, recommendations were made for implementing fishing gear regulations and adopting a community-based co-management system.</p> Ikongbeh, O. A. Ataguba G. A. Omuwa, J. W. Copyright (c) 2024 Nigerian Journal of Fisheries and Aquaculture 2024-05-29 2024-05-29 12 1 26 36 Acute Toxicity of Hydrated Lime (Calcium hydroxide) to Clarias gariepinus Fingerlings <p style="margin: 0cm; text-align: justify;"><span lang="EN-GB" style="font-size: 10.0pt;">The acute toxicity of hydrated lime to fish is a critical concern in aquatic environments, as it can neutralize acidic gases, potentially reducing the toxicity of gaseous products. Understanding its acute toxicity levels is essential for assessing the immediate adverse effects of substances on organisms, including fish. This study aimed to determine the 96-hour LC<sub>50</sub> acute toxicity of hydrated lime (calcium hydroxide) on fingerlings of the African catfish <em>Clarias gariepinus</em>. The acute toxicity of calcium hydroxide (hydrated lime) on the fingerlings of <em>C. gariepinus</em> (mean weight and length 5.8±0.2g and 4.2 ± 0.3cm, respectively) was investigated under laboratory conditions in a static bioassay. Fish were exposed for 96 hours to various concentrations of 280 mg/L, 272 mg/L, 264 mg/L, 256 mg/L, 248 mg/L, and 0.0 mg/L, each treatment having a replicate aeration system. The mortality of <em>C. gariepinus</em> fingerlings exposed to different concentrations of calcium hydroxide was found to be directly proportional to an increase in the concentration of the substance. The 96-hour LC<sub>50</sub> was 268 mg/L, with upper and lower limits of 272.375 mg/l and 263.695 mg/L, respectively. This indicates that as the concentration of calcium hydroxide increased, so did the mortality rate of the fish, with no mortality observed in the control group. The presence of calcium hydroxide in water can pose a threat to fish species and other aquatic organisms due to its toxic properties.</span></p> Omuwa J. W. Ataguba G. A. Yusufu F. O. Copyright (c) 2024 Nigerian Journal of Fisheries and Aquaculture 2024-05-29 2024-05-29 12 1 37 43 Acute Toxicity and Clinical Response to Lead Acetate by the African Catfish, Clarias gariepinus (Burchell, 1822) <p>This study investigated the acute toxicity of lead acetate on <em>Clarias</em> <em>gariepinus</em> under laboratory conditions.&nbsp; Two hundred (200) <em>Clarias gariepinus</em> (185 ± 5 g weight and 27-36 cm length) were purchased from a commercial fish farm in Zaria. The fish were transported to the laboratory in a well-aerated 50-liter Jerrican half-cut with water.&nbsp; The fish were allowed to acclimatize for 14 days, during which they were fed commercial feed (42.0% crude protein) twice daily. A preliminary toxicity range-finding test was carried out using 20 fish. The outcome obtained from the range-finding test provided a guide for the acute toxicity study. The acute toxicity test was carried out using six of 10 fish per group in triplicate via static no-renewable bioassay procedure in 40-liter aquariums (76 cm <em>× </em>38 cm <em>× </em>38 cm) per group. The various concentrations of lead acetate used were G1 (0 mg/L), G2 (140 mg/l), G3 (145 mg/l), G4 (150 mg/l), G5 (155 mg/l) and G6 (160 mg/l) for 96-hour period. The fish samples exhibited varying behavioral and physical changes which range from erratic swimming, off-feeding, frequent gasping for air at the surface of the aquarium, skin discoloration, and eventual death. The vigor and severity of these features were time and concentration-dependent. The result showed that 96hours LC<sub>50</sub> of <em>Clarias gariepinus </em>was 150.7mg/L. This indicates that a larger quantity of lead acetate is needed to cause mortality in the fish and is less harmful at lower concentrations.</p> Abdulsalam H. Sani D. Tijani A. A. Gadzama J. J. Chiroma M. A. Salihu S. I. Bello U. Sambo S. J. Bisalla M. Adamu S. Copyright (c) 2024 Nigerian Journal of Fisheries and Aquaculture 2024-05-29 2024-05-29 12 1 44 52 Evaluation of Sargassum fluitans (Borgessen, 1914) As an Alternative Energy Source in the Production of Feeds for African Catfish (Clarias gariepinus, Burchell, 1822) <p style="margin: 0cm; text-align: justify;"><span lang="EN-GB" style="font-size: 11.0pt;">The study investigated the possibility of utilizing seaweed (<em>Sargassum</em> <em>fluitans</em>), as an alternative source for maize in the diet of <em>Clarias gariepinus. Sargassum</em> <em>fluitans</em> were collected by handpicking during low tides from the shores of Suntan Sea Beach, Badagry, Lagos State, Nigeria. The seaweed was washed thoroughly with borehole water, rinsed with distilled water, and sun-dried for 1 week. The experimental diet consists of a control; ingredients including maize but no <em>Sargassum</em> meal at all as treatment 1, 5% maize meal replaced with <em>Sargassum</em>&nbsp;as treatment 2, 10% of maize meal replaced with <em>Sargassum</em> as treatment 3, 20% of maize meal replaced with <em>Sargassum</em>&nbsp;as treatment 4, <em>Sargassum</em> only, no maize at all, as treatment 5. A total of 180 fingerlings of <em>Clarias gariepinus (</em>20–25 g weight and 14–16 cm in length) were stocked in 1000-litre capacity tanks at the rate of twenty (20) fish per tank. The various proportions of sargassum replacing maize were allotted to the fish stocked in the tanks in replicate.&nbsp; The fish were reared for 3 months on the experimental diet. The results showed that fish fed with Sargassum only (no maize) had the highest (43.14±9.57%) growth performance index, followed by the control diet (38.15±8.76%). However, fish fed a 10 % <em>Sargassum </em>diet had the lowest (34.86±7.66%) growth performance index. In conclusion, <em>Sargassum</em> is a potential alternative to maize in the diet of <em>C. gariepinus</em>. <em>Sargassum</em> is 100% free, and its processing is very cheap. Hence, catfish farmers can increase their income by reducing the cost of feed used for their fish.</span></p> Anetekhai M. A., Clarke E.O. Mekuleyi G.O. Badmos L.A. Copyright (c) 2024 Nigerian Journal of Fisheries and Aquaculture 2024-05-20 2024-05-20 12 1 60 60