Asian Journal of Fisheries and Aquatic Research

This research aimed to analyze the relationship of factors that influence consumer behavior in the purchase decision of freshwater fish in Kosambi Traditional Market. The research was conducted in March 2019 to March 2020. The method used in this research was a case study. The sampling technique was used accidental sampling method with 100 respondents. To analyze the behavior of consumers used attitude measurement analysis as measured by a Likert Scale. Correlation of qualitative data is used to analyze the relationship of factors that influence consumer behavior in freshwater fish purchasing decisions. The results showed that four factors that influenced the purchase decision of freshwater fish products had a significant relationship with the correlation coefficient values as follows: Cultural factors of 0.243, Social factors of -0.278, Personal factors of 0.631, and psychological factors of 0.427. Personal factor is the more dominant variable influencing and being considered by consumers in deciding to purchase freshwater fish because the personal factors are defined as psychological characteristics of a person that is different from others that causes relatively consistent and long-lasting responses to the environment.

Aim: Eco-morphological studies show that morphological traits are adaptive, which means that traits evolve and change as a result of the activities going on in the environment such as predation, competition, and other biotic associations. This study was taken to determine the eco-morphological patterns of some fishes from the Ogu River in Ogu/Bolo Local Government Area of Rivers State, Niger Delta, Nigeria.

Study Design: Field work and random sampling.

Place and Duration: Three stations were sampled along the Ogu river and the duration of the study was four months (January- April 2018).

Methodology: A total of 193 individual fishes were caught, comprising of 5 families and 11 species. Fish samples were obtained with the aid of a seine net; identified, weighed and morphometric measurements were made, to provide the eco-morphological attributes. Fishes were dissected to measure intestinal length. Statistical analysis includes Principal Component Analysis (PCA) of morphometric ratios and intestinal length - total length ratios of fish.

Results: The fish species found were Tilapia guineensis, Tilapia zilli, Mugil bananensis, Mugil curema, Liza falcipinnis, Liza dumerili, Liza grandisquamis, Pomadasys rogerii, Pomadasys jubelini, Lutjanus endecacanthus and Eucinostomus melanopterus. Tilapia guineensis was the most abundant species, Shannon Weiner diversity index (H) ranged from 1.83 - 1.96, Simpson’s dominance index ranged from 0.79 - 0.85. The PCA analysis using different morphological attributes revealed 4 groups in feeding regime (omnivorous - Mugilids; herbivorous - Cichlids; larger carnivores - Lutjanids and smaller carnivores - Pomadasyids), and 3 groups in the fishes habitat preference in water as (1: Cichlids, 2: Mugilids and 3: Pomadasyids, Lutjanids and Gerreids).

Conclusion: This study revealed morphometric attributes of some fishes of the Ogu river in Rivers State Nigeria and their relation with feeding, microhabitat and environmental parameters.

Population parameters for two commercially important fishes of Sciaenidae from the coastal waters of Ghana were assessed using length-frequency data obtained from August 2017 to June 2019. Samples of the assessed fish species were obtained through experimental fish trawl along the coast of Greater Accra, Ghana. Trawling was performed every quarter for an average of one hour at an average speed of 3.0 km/hr. In all, a total of 399 samples were measured and the obtained data were analyzed with FiSAT II. The assessed fish species included Pteroscion peli (165 samples) and Pseudotolithus senegalensis (234 samples). The asymptotic length (L∞) was 19.4 cm and 41.5 cm forPteroscion peli and Pseudotolithus senegalensis. Pteroscion peli and Pseudotolithus senegalensis recorded growth rate (K) of 0.48 and 0.50 per year respectively. Both assessed fish species exhibited continuous recruitment pattern with minor and major recruitment peaks. The total mortality rate (Z) was 1.86 and 1.63 per year for Pteroscion peli and Pseudotolithus senegalensis. The fishing mortality rate (F) was estimated at 0.66 and 0.63 per year for Pteroscion peli and Pseudotolithus senegalensis. The natural mortality rate (M) estimated for Pteroscion peli and Pseudotolithus senegalensis was 1.20 and 1.00 per year respectively. The exploitation rate (E) of Pseudotolithus senegalensis (0.39) and Pteroscion peli (0.36) respectively was far below the maximum exploitation rate (E_max), indicating under-exploitation of its fishery in the coastal waters of Ghana, hence the need to enhance the exploitation of these species.

The probiotic bacteria isolated from prawn, Macrobrachium rosenbergii was studied for their morphological and biochemical characteristics as well as their antagonistic efficacy against pathogenic bacteria. A total of three probiotic bacteria viz. White Colour Bacteria (WCB), Red Colour Bacteria (RCB) and Yellow Colour Bacteria (YCB) were isolated from intestine of healthy prawn while three pathogenic bacteria viz. PB1, PB2 and PB3 were isolated from infected antennae and muscles of moribund prawn. Depending on their physical and biochemical features, the probiotic isolates were gram-positive, rod shaped and motile bacteria belonging to Bacillus spp. and the pathogenic bacteria were also identified as gram-negative, cocci shaped and motile bacteria fit in Enterococcus spp., Vibrio spp. and Micrococcus spp. The optimum culture conditions of all isolates were at pH 7.0 and 37°C temperature. Results on the antibiogram profile of pathogenic bacteria revealed that majority of the isolates were sensitive (43.58%) or intermediate (30.76%) against thirteen antibiotics. The probiotic bacterial antagonistic activities were tested against Enterococcus, Vibrio and Micrococcus spp.by cross-streak method. The results indicate that the strain of YCB showed inhibitory effects against Enterococcus spp. (5 mm), Vibrio spp. (5 mm) and Micrococcus spp. (3 mm). Similarly, WCB showed inhibitory effects against Enterococcus spp. (4 mm), Vibrio spp. (3 mm) and Micrococcus spp. (4 mm). RCB strains showed inhibition against Micrococcus spp. (3 mm) only, but not against Enterococcus spp. and Vibrio spp. Based on the results, it can be concluded that the isolated probiotic bacteria could be a good candidate to consider for further studies to control the pathogenic bacteria in prawn culture.

The present study describes the food and feeding habits, Length- weight relationship and condition factor in Cat fish Mystus armatus. Food contents was measured by frequency of occurrence method. Length-weight relation was measured by correlation regression equation method LogW=aL^b. The length weight relationship indicates that relationship between length-weight is allometric growth having high values of b withR²> 0.56 with CI of 95%. The values of condition factor varies from 0.70 to 0.88.  The present study is useful to study conservation and sustainable fisheries management. It was concluded that Mystus armatus is carnivorous feeder, length weight relationship is significant, and fish is in poor condition due to various conditions of water.