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Papers by OLAYINKA ANIFOWOSE

Journal of Aquaculture, Marine Biology & Ecology, 2020

Motile Aeromonas Septicaemia (MAS) known to be the commonest bacterial infection of cultu... more Motile Aeromonas Septicaemia (MAS) known to be the commonest bacterial infection of cultured fish is mostly ascribed to Aeromonas hydrophila. This study was therefore conducted to determine the pathogenicity of Aeromonas bestiarum in fry, juvenile and post-juvenile of Clarias gariepinus, and evaluate the antibiotic sensitivity profile of the organism for effective control. Aeromonas bestiarum was isolated from dead fry in Ijebu Ode. The organism was characterized and used for this study. Two-hundred apparently healthy fry collected from a commercial hatchery were randomly divided into four experimental groups of 50 fry. Three groups were infected with 1x108 (cfu)/ml of Aeromonas bestiarum by immersion in 2L of water, while the fourth groups were not infected. Fish in the infected and control groups were monitored daily for 21 days for signs of infection and mortality. The cumulative mortality in fry, juvenile and post-juvenile was 85%, 82% and 50% respectively. Gross lesions observed in post-juvenile fish were bulgy eyes, swollen dorsal muscle caudal to the cranium, congested kidney and skin depigmentation. Histological lesions were equally recorded in the hepatic tissue, diffuse degeneration and necrosis of the tubular epithelium in the interstitium of kidney. It was re-isolated from infected fish in the different developmental stages, while the organism was observed to be sensitive to two antibiotics. Groups of survivors in the different stages were treated for five days. On the second day of treatment, there was 15%, 14% and 0% mortality in the treated fry, juveniles and post-juveniles respectively, while the mortality rate of untreated but infected group (control) were 40%, 42% and 42% for fry juveniles and post-juveniles fish respectively. This shows Aeromonas bestiarum causes high mortality in fry, juvenile and post-juvenile of Clarias gariepinus. It's however sensitive to Enrofloxacin and Gentamicin which can be used for treatment of infection by Aeromonas bestiarum for now.

International Journal of Fisheries and Aquatic Studies, 2021

The study investigated the causal factors associated with mass mortality of hatchery-reared Clari... more The study investigated the causal factors associated with mass mortality of hatchery-reared Clarias gariepinus Burchell 1822 fry during exogenous feeding. A feeding trial and fry re-infection trial were conducted using four different starter diets. The food samples were fed to 480 post-yolk-absorbed fries for 21 days in two replicates. Samples of dead fry were cultured for bacteria using standard methods. The total aerobic and coliform were significantly higher in all food samples, meanwhile, alkaline pH (9.25±0.34) and low dissolved oxygen (4.5±1.08) were not significantly different (P>0.05) in all water tanks. The bacterial pathogens isolated from dead fries were Aeromonas hydrophila Stainer, 1943 and Pseudomonas aeruginosa Migula, 1990, whereas significantly higher mortality in experimentally infected fry was observed (α < 0.05).
Mass mortality of C.gariepinus fry observed in this study was associated with bacterial pathogens, bacterial contamination of food, alkaline pH, and low dissolved oxygen

Alexandria Journal of Veterinary Sciences, 2021

Fungal contamination of poultry feedstuffs can lead to nutrient losses and serious harm to poultr... more Fungal contamination of poultry feedstuffs can lead to nutrient losses and serious harm to poultry production and public health. This study was designed to evaluate the hygienic condition and the level of fungal contamination affecting the quality of poultry feeds (Broiler and Layer feed) during the rainy season (April – September) in Ogun State, Nigeria. A total of 60 samples of mashed poultry feeds (30 broiler and 30 layer feeds) were collected from farms in Ogun state. Samples were cultured on Sabouraud dextrose agar, the Colony forming units (CFUs) were calculated, and the taxonomic identification of various fungal genera was made macroscopically. Fungal counts for layer feeds (8.6 ×103) were significantly P < 0.05 higher than broiler feeds (4.2 ×103). Among the feed samples, 13 (43%) broiler feed and 16 (53%) layer feed samples exceeded the accepted European standard for finished poultry feed (1×103 CFU g-1), from a total of 60 feed samples, 29(48.3%) samples exceeded the standard limits. The most frequent fungal genus recovered were Aspergillus sp. (53%, 50%) and Fusarium sp. (12%, 10%) in broiler and layer feeds respectively. The poultry feeds from some farms in Ogun state were contaminated with various fungal genera by different levels in which 48% of the samples were higher than the standard limits. Contamination with potentially mycotoxigenic fungi especially Aspergillus sp. was 50%, Fusarium sp. was 10% and their presence in feed poses a health hazard for poultry birds.

Journal of Aquaculture, Marine Biology & Ecology, 2020

Motile Aeromonas Septicaemia (MAS) known to be the commonest bacterial infection of cultu... more Motile Aeromonas Septicaemia (MAS) known to be the commonest bacterial infection of cultured fish is mostly ascribed to Aeromonas hydrophila. This study was therefore conducted to determine the pathogenicity of Aeromonas bestiarum in fry, juvenile and post-juvenile of Clarias gariepinus, and evaluate the antibiotic sensitivity profile of the organism for effective control. Aeromonas bestiarum was isolated from dead fry in Ijebu Ode. The organism was characterized and used for this study. Two-hundred apparently healthy fry collected from a commercial hatchery were randomly divided into four experimental groups of 50 fry. Three groups were infected with 1x108 (cfu)/ml of Aeromonas bestiarum by immersion in 2L of water, while the fourth groups were not infected. Fish in the infected and control groups were monitored daily for 21 days for signs of infection and mortality. The cumulative mortality in fry, juvenile and post-juvenile was 85%, 82% and 50% respectively. Gross lesions observed in post-juvenile fish were bulgy eyes, swollen dorsal muscle caudal to the cranium, congested kidney and skin depigmentation. Histological lesions were equally recorded in the hepatic tissue, diffuse degeneration and necrosis of the tubular epithelium in the interstitium of kidney. It was re-isolated from infected fish in the different developmental stages, while the organism was observed to be sensitive to two antibiotics. Groups of survivors in the different stages were treated for five days. On the second day of treatment, there was 15%, 14% and 0% mortality in the treated fry, juveniles and post-juveniles respectively, while the mortality rate of untreated but infected group (control) were 40%, 42% and 42% for fry juveniles and post-juveniles fish respectively. This shows Aeromonas bestiarum causes high mortality in fry, juvenile and post-juvenile of Clarias gariepinus. It's however sensitive to Enrofloxacin and Gentamicin which can be used for treatment of infection by Aeromonas bestiarum for now.

International Journal of Fisheries and Aquatic Studies, 2021

The study investigated the causal factors associated with mass mortality of hatchery-reared Clari... more The study investigated the causal factors associated with mass mortality of hatchery-reared Clarias gariepinus Burchell 1822 fry during exogenous feeding. A feeding trial and fry re-infection trial were conducted using four different starter diets. The food samples were fed to 480 post-yolk-absorbed fries for 21 days in two replicates. Samples of dead fry were cultured for bacteria using standard methods. The total aerobic and coliform were significantly higher in all food samples, meanwhile, alkaline pH (9.25±0.34) and low dissolved oxygen (4.5±1.08) were not significantly different (P>0.05) in all water tanks. The bacterial pathogens isolated from dead fries were Aeromonas hydrophila Stainer, 1943 and Pseudomonas aeruginosa Migula, 1990, whereas significantly higher mortality in experimentally infected fry was observed (α < 0.05).
Mass mortality of C.gariepinus fry observed in this study was associated with bacterial pathogens, bacterial contamination of food, alkaline pH, and low dissolved oxygen

Alexandria Journal of Veterinary Sciences, 2021

Fungal contamination of poultry feedstuffs can lead to nutrient losses and serious harm to poultr... more Fungal contamination of poultry feedstuffs can lead to nutrient losses and serious harm to poultry production and public health. This study was designed to evaluate the hygienic condition and the level of fungal contamination affecting the quality of poultry feeds (Broiler and Layer feed) during the rainy season (April – September) in Ogun State, Nigeria. A total of 60 samples of mashed poultry feeds (30 broiler and 30 layer feeds) were collected from farms in Ogun state. Samples were cultured on Sabouraud dextrose agar, the Colony forming units (CFUs) were calculated, and the taxonomic identification of various fungal genera was made macroscopically. Fungal counts for layer feeds (8.6 ×103) were significantly P < 0.05 higher than broiler feeds (4.2 ×103). Among the feed samples, 13 (43%) broiler feed and 16 (53%) layer feed samples exceeded the accepted European standard for finished poultry feed (1×103 CFU g-1), from a total of 60 feed samples, 29(48.3%) samples exceeded the standard limits. The most frequent fungal genus recovered were Aspergillus sp. (53%, 50%) and Fusarium sp. (12%, 10%) in broiler and layer feeds respectively. The poultry feeds from some farms in Ogun state were contaminated with various fungal genera by different levels in which 48% of the samples were higher than the standard limits. Contamination with potentially mycotoxigenic fungi especially Aspergillus sp. was 50%, Fusarium sp. was 10% and their presence in feed poses a health hazard for poultry birds.