http://hdl.handle.net/123456789/327 2026-04-06T02:25:17Z http://hdl.handle.net/123456789/340 THE EFFICACY OF RAW GARLIC (ALLIUM SATIVUM) BATH IN AMELIORATING CADMIUM AND LEAD TOXICITY IN CULTURED CLARIAS GARIEPINUS BURCHELL, 1822 OJOGBO, AUGUSTINE ISIKWEI Cadmium (Cd) and Lead (Pb) are toxic metals ubiquitous in the aquatic environment, inducing reactive oxygen species that cause stress, toxicity and mortality in fish. Organic source such as allicin extracted from garlic reversed this toxicity; however, there is a dearth of information on the use of raw organic source to reverse these conditions. This study was designed to explore the potentials of raw garlic (Gc) in ameliorating the toxic effects of these metals in cultured Clarias gariepinus (Cg). Two hundred and forty apparently healthy Cg juveniles were exposed in four triplicate groups (20 per group/10 per sex) to garlic A; 8.0g /L, B; Cd 0.03mg/L, C; Pb 0.3mg/L, and D the control in static culture for 90 days. Also four hundred and eighty randomly-selected female Cg juveniles of 20 fish each were exposed to Cadmium alone, Cadmium + Gc1 and Gc1 or Gc2 only. Cadmium was replaced with lead and cadmium + lead in other experiments. Cadmium, lead, Gc1 and Gc2 were given at 64, 126, 0.65 and 0.87 mg/L, respectively. Exposure to metals was for six-hours followed by six-hours in freshwater before 12-hours garlic treatment for two consecutive days. Clinical signs for toxicity were monitored for 120-hours. Tissue concentration of metals, oxidative stress markers, gross and histopathology of tissues were also conducted using standard methods. Data were analysed using ANOVA and DMRT at α0.05. Group A at forty-eight hours post-exposure manifested vertical positioning in 40.0% of fish. At day 30, scanty degenerate germinal cells were observed in group B while there were no visible lesion in the testis of group A fish at day 90. At day 90 female liver Pb concentration decreased in A (91.5%), increased in B (11.4%) and C (73.5%) groups relative to control. Also Cd, Pb and their combinations groups induced 60.0 – 90.0% vertical positioning and copious mucus secretion. There was also 5.0% mortality at six-hours exposure in Cd + Pb group. At 120-hours glucose decreased in Pb + Gc2 (7.9%), Pb (36.4%) and increased in Gc2 (9.8%) groups. At 120-hours intestinal manganese level increased in Cd + Gc1 (79.4%) and decreased in Cd (58.6%) while hydrogen peroxide level in the liver decreased in Cd + Gc1 (17.3%) and increased in Cd (16.4%) groups. Malondialdehyde level in the liver decreased in Pb + Gc2 (20.0%) and increased in Pb only (8.0%) while superoxide dismutase level increased in Gc2 (7.1%) groups. Spleenic congestion, goblet cell hyperplasia, neuronal necrosis of the brain, hepatocellular necrosis, hypochromasia, poikilocytosis, and rouleux formation were observed in all groups exposed to the metal(s). The severity of these lesions decreased with garlic bath vi at 120-hours. Micronuclei were observed in Cd + Pb at six-hour post-exposure and Pb group at 120-hours. Exposure to garlic reversed the deleterious effects of Cadmium and Lead, suggesting its efficacy in the detoxification of Cadmium and Lead toxicity in cultured fish. It is recommended that fish farmers use at least 0.65mg/l of raw garlic to reduce the lethal effects of these metals on farmed Clarias gariepinus. Keywords: Clarias gariepinus, Reactive oxygen species, Cadmium and lead, Garlic toxicity treatment. Word count: 498. 2016-06-01T00:00:00Z http://hdl.handle.net/123456789/328 DETECTION AND GENETIC TYPING OF ROTAVIRUS IN SOME AVIAN SPECIES FROM SOUTHWESTERN NIGERIA ONI, OLUWOLE OYETUNDE Rotaviruses are leading causes of acute viral gastroenteritis in humans and animals worldwide. The disease causes substantial economic loss to the poultry industry due to decreased weight gain, increased production costs and mortality. Despite its broad distribution among humans and animals, avian rotaviruses have not been detected in Nigeria. This study was aimed at designing primers for avian rotavirus detection, characterising gene segments critical for vaccine development and determining genetic relatedness of detected rotavirus strains. A total of 464 faecal samples from chickens (360), crowned cranes (9), ducks (10), eagles (2), geese (7), guinea fowls (33), parrots (3), pigeons (27) and turkeys (13) from some poultry farms were examined between June 2009 and March 2013. Degenerate primers and one step reverse transcription–polymerase chain reaction protocol were designed for detection of VP4, VP6 and VP7 segments. Four primer pairs were designed for VP4 segment and two pairs each for VP6 and VP7 segments. In addition, two previously published primer pairs were used for detection of VP6 and NSP4 segments for a complete coding sequence of each segment. The segments were characterised by nucleotide (nt) and amino acid (aa) sequence analysis using BioEdit® sequence alignment editor and the online rotavirus classification tool (RotaC®). Phylogenetic analysis was conducted using MEGA version 5. Genes encoding VP6, VP7 and NSP4 segments were detected in 129 faecal samples of chickens (124), crowned cranes (2), eagle (1), guinea fowl (1) and parrot (1). The designed primers had specific bands and were efficient for detecting rotavirus in all positive faecal samples than previously published primers due to the inclusion of degenerate nucleotides. All characterised strains possessed VP6, VP7 and NSP4 sequences typical of rotavirus A. Only 3 partial VP4 sequences were characterised from the positive samples. These VP4 sequences had low similarity between 68% and 72% to sequences of other known rotaviruses except Ch-06V0661, which has an encoding sequence of unknown host origin. The VP4 segments of other strains in this study were untypeable. The basic structure of the VP6 encoding gene was 1348 nt long with open reading frame beginning at nt 24, terminated at nt 1214 and coded for 397 aa. This segment also had 88.1% to 95.4% similarity with genotype I11 strains. However, reassortment of chicken VP6 segment occurred in the conserved aa sequence at antigenic site I (aa 45–65) with a change from alanine to threonine at aa 60. The VP7 and NSP4 genes showed aa identities between 89.5% to 96.7% and 91.8% to 93.3% with strains belonging to genotype G19 and E10 respectively. These rotaviruses belong to group A, genotypes I11, G19 and E10 with an untypeable VP4 segment. All characterised segments clustered closely with avian strains except the VP4 segment indicating reassortment and portend a public health hazard based on its zoonotic ability. The reassortment in conserved antigenic site also provides additional evidence for the wide genetic and antigenic diversity of group A rotaviruses. This appears to be the first report of avian rotavirus detection in Nigeria. Keywords: Avian rotavirus, Untypeable VP4, Genetic reassortment. Word count: 497 2015-03-01T00:00:00Z