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MOLECULAR AND ANTIGENIC CHARACTERISATION OF INFLUENZA VIRUSES ISOLATED FROM HORSES IN NIGERIA
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Page will reload when a filter is selected or excluded.- Clarias gariepinus 3 results 3
- Growth 2 results 2
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- Performance 2 results 2
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- A general survey of phytoparasitic nematodes associated with yam (Dioscorea spp.) in the Mid-Western State of Nigeria showed that Seutellonema bradys and Meloidogyne spp. were the economically important nematodes of yam tubers. S. bradys was associated with the ’dry rot' of yam tubers causing storage losses estimated between 80 and 100%. Nematodes of the genus Meloidogyne were found associated with galling of tubers of water yam (D. alata). Studies on the rate of population build-up of S. bradys in storage showed that S. bradys increased 9-fold, 8-fold and 5-fold in the tubers of D. rotundata, D. cayenensis and D. alata respectively during 6 months of storage. These increases in population influenced the severity of ’dry rot’ disease. Results of investigations into the depth of penetration of S. bradys in 5 different varieties of D. rotundata showed that there were differences in varietal susceptibility. The bulk of the nematode population was found in the periderm to a depth of between 0-1.5 cm, but depth of penetration was greater in the head portions of each of the tubers than either the middle or bottom portions. Observations on the activities of the nematodes in tuber tissues (histopathology) suggested that the 'dry rot' was mainly due to mechanical damage to the cells and the host reaction to intracellular feeding by S. bradys. Studies on changes in the carbohydrate constituents of the yam tuber infected by S. bradys showed an increase in the percentages of monosaccharides and disaccharides like sucrose, glucose and galactose, fruobose with a concomitant decrease in starch, amylose and amylopectin when compared with healthy yam. Qualitative and quantitative determination of amino acid constituents of nematode-infected tubers of white yam (D. rotundata). yellow yam (D. cayenensis) and water yam (D. alata) showed that the relative numbers of free amino acids were not materially changed following infection by 5, bradys. but a reduction occurred in the number of 'essential' amino acids in the infected tubers. Eighteen ninhydrin positive amino acids were detected in the protein hydrolysate. Except in the case of white yam and in a few other cases, increases in protein amino acids were recorded in the infected tubers of yellow and water yam. The percentage protein was also increased by infection in all species except white yam (D. rotundata). Observations on the rate of weight loss (cumulative percentage weight and mean percentage weight loss) in 3 different species of Dioscorea stored in a yam barn showed that there was a significant difference in the rate of weight loss between nematode-infected and nematode-free tubers of D. rotundata and D. cavenensis, but no significant difference was recorded between the infected and healthy yam tubers of D. alata. Estimation of the edible portions in nematode-infected and nematode-free tubers of D. rotundata. D. cavenensis and D. alata showed a significant difference in the percentage peeling losses between the infected and healthy tubers. Chromatographic analysis of the incubation solution of S. bradys showed that 5 amino acids - aspartic acid, phenylalanine, hydroxylnol acetic acid, leucine and isoleucine were discharged by this nematode. The absence of the steroid group of compounds in the nematode-infected yam tubers revealed by spectrometrie analysis might be disease-related as evidenced by its appearance in the healthy tubers. Polygalacturonase and amylase activities were detected in homogenates of S, bradys. Studies on fungi associated with the dry rot disease of yam tubers showed Aspergillus niger. Penicillium sclerotigenum. Triohoderma viride. Rhizopus nigricans and Fusarium oxvsporum. Botrvodiplodia theobromae and Fusarium moniliforme as the main species. Studies on the possible interrelationshipsbetween S. bradys and 3 fungi A. niger. P. sclerotigenum and F. oxysporum showed that the presence of the nematode seemed to increase the degree of pathogenicity of Fusarium and Penicillium species on yams. But the presence of S. bradys did not increase the degree of pathogenicity of Aspergillus niger. In greenhouse experiments, the interaction between S. bradvs and A. niger was found to be disadvantageous to the nematode. The presence of the fungus seemed to have some effect on the number of nematodes that invaded the roots and tubers and subsequently on nematode development. This was thought to be due to an anti-biotic action of A. niger on S. bradys. A host range study of 30 crop plants and weeds revealed that beniseed (Sesamum indicum L.), cowpea (Vigna unguioulata (L.) Walp.), were good alternative hosts of S. bradys. Small populations of the nematode also survived endoparasitically in the roots of Bupatorium. avnedrella. roselle faib1scus sab dar if f a L.). kenaf (Hibiscus cannabinus L.), melon (Cucurbita pepo L.); jute (Corchorus olitorius L.); yam bean (Sphenostylis stenocarpa) (Hochst ex A Rich) Harms., soko (Oelosia araentia L.) and pigeon pea (Ca.lanus ca.ian (L.) Druce). Non-hosts included maize and tobacco. Dipping nematode-infected tubers of D. alata and D. cayenensis in hot water at temperatures ranging between 50 and 60°C for 40 minutes completely eliminated the nematode. However, at temperatures above 55°C for an exposure time of 1+0 minutes, the tubers so treated suffered a physiological damage and rotted very rapidly. Temperatures between 50 and 55°C had no adverse effect on percentage emergence, growth, yield and palatability of tubers of D. alata. Field trials on chemical and cultural control of S. bradys on D. alata showed that the yield of yam was increased and the nematode population suppressed by the application of organic manure at the rate of 1.5 kg/heap or 1 ,886.3 kg/ha. Although the application of nemagon at the rate of 35.2 kg/ha. considerably suppressed nematode population, the yield of yam was significantly reduced. The results showed that there is a good deal of potential for experimentation with various cultural methods of nematode control. Studies on the effect of gamma irradiation on S. bradys showed that dosages between 5 and 15 Krad did not eliminate the nematodes completely, but suppressed sprouting and signs of deterioration in tubers. Dosages between 20 - 30 Krad eliminated about 70 - 80% of the nematode population. 1 results 1
- A nationwide equine influenza virus surveillance was carried out between January 1989 and January 1995 during which nasopharyngeal swabs, tracheal washes and respiratory tract tissue homogenates were obtained from symptomatic and asymptomatic equine species in various parts of Nigeria for virus isolation and characterisation. Three equine influenza viruses were independently isolated in 10-11 day old embryonated hen eggs and Madin Darby canine kidney monolayer cells with TPCK-trypsin incorporated into the culture medium. The virus isolates were characterized antigenically, immunogenically and genetically which made them the first equine influenza viruses isolated and characterized in tropical Africa. Antigenic analyses with mono-specific antisera raised against a number of respiratory disease viruses including Paramyxoviruses, Adenoviruses, Herpes viruses, Alphavirus, Rhinoviruses, Equine arteritis viruses, African horse sickness viruses and Influenza viruses showed that the three virus isolates were influenza A viruses while haemagglutination and neuraminidase inhibition assays using influenza virus specific Mabs and polyclonal antisera showed the three viruses to be antigenically H3N8, members of equine-2 subtype of influenza A viruses. The three isolates were respectively named A/Equine/Ibadan/4/91, A/Equine/Ibadan/6/91 and A/Equine/Ibadan/9/91 in accordance with the recommendations of the World Health Organisation and the International Committee on Virus Taxonomy. Their antigenic cross-reactivity with panels of Mabs and polyclonal antisera indicated that the three viruses were antigenically divergent although they were all H3N8 viruses and were representatives of a homogenous population. They were reactive with Mabs and antisera directed against H3 equine viruses isolated in 1963, 1976, 1979, 1981 and 1986. This broad reactivity suggested that these isolates were similar to but not still different from those isolated in Europe and USA between 1963 and 1987. Virus protein synthesis and cleavability of the HA polypeptide in tissue culture were investigated by pulse-chase experiments. The results showed some heterogeneity in the non-glycosylated polypeptides particularly those of the ribonucleoprotein (RNP) complex while the HA glycoproteins of the three viruses were not cleaved in any of the cell types used in contrast to equine H7 and pathogenic avian H5 and H7 HAs. The molecular weights of the polypeptides were within the range previously determined for influenza A viruses. The heterogeneity of the RNP complex and antigenic divergence of the viruses’ HAs were confirmed by sequence analysis carried out in molecular studies. Virus infectivity was investigated by plaque assay using chicken embryo fibroblast (CEF) monolayer cells and virus titration in embryonated hen eggs. The results showed that the viruses were infectious with plaguing efficiency being comparable to efficiency of virus infectivity in embryonated hen eggs. Infectivity, antigenicity and immunogenicity of the three viruses were confirmed in-vitro using peripheral blood lymphocytes in lymphoproliferation assays and in-vivo in an equine model in which the viruses induced haemagglutination inhibiting and protective neutralising antibodies following experimental infections. The proliferating cells were also characterised and the immunoglobulin isotypes produced were determined. Molecular characterisation and genetic analyses of the three viruses were accomplished to determine the origin of the genes encoding the virus non-glycosylated polypeptides as well as those of the surface HA glycoprotein. Reverse transcription (RT) results showed the eight RNA segments of the three isolates and confirmed them as influenza A virus RNAs. No subgenomic RNAs or defective interfering particles were observed in the RNA transcripts. Nucleotide sequence analyses were carried out using three sequencing strategies of cDNA, vRNA and plasmid DNA sequencing with the dideoxy chain termination procedure. Partial nucleotide sequences were obtained from cDNAs, vRNAs and plasmid DNA clones of RNA segments 1, 2, 3, 5, 7 and 8 with the method of multiplex RT/PCR and cycle sequencing using radiolabelled segment specific oigonucleotides of 18, 24 or 25 mers. Complete nucleotide sequences of segment 4 (HA genes) were also determined on the same PCR products (cDNA) and vRNA using end-labelled oligonucleotides of both plus and minus sense. The partial nucleotide sequence data were analysed using a programme for "best-local-homology- rapid-search" on a digital array processor while the complete HA nucleotide and deduced amino acid sequence analyses were carried out using the University of Wisconsin Genetics Computer Group (GCG) package of programmes. Phytogenetic analysis was done with the distances, neighbour joining and DNAPARS of the PHYLIP package. Analyses of the viruses’ gene sequences confirmed that their genomes were similar to each other and to those of other H3N8 influenza viruses isolated from equines and also revealed the origin, evolution and genetic relatedness of the genes. Comparison of the partial cDNA sequences with virus DNA sequences in the database (EMBL sequence library) showed that for segments 1, 2, 5, and 7, the closest related sequences were from equine H3 viruses isolated in 1986 in USA (Tennesse/5/86 for segments 2, 5 and 7, Kentucky/2/86 for segments 1 and 5. Segment 5 was equally related to both viruses). The nucleotide sequence for segment 3 was most closely related to an equine-1 virus isolated in U.K. in 1973 (London/1416/73, H7N7) probably due to genetic exchange while segment 8 sequence was most closely related to an equine H3N8 virus isolated in U.K. in 1976 (Newmarket/76). The complete nucleotide and deduced amino acid sequences as well as phytogenetic analysis of the HA genes (RNA segment 4) showed a closer relationship albeit with nucleotide and amino acid substitutions between the three Ibadan viruses and those that were isolated in Europe in 1989 and 1991, the prototypic European strain, Suffolk/89 and Arundel/12369/91 isolated in U.K., Taby/91 isolated in Sweden, Hong Kong/92 isolated in the Far East in 1992 and Laplata/1/93 isolated in South America. These findings group the Ibadan viruses with those predominating and contemporarily causing disease in the Western Hemisphere rather than with viruses previously isolated from the north and south of African continent. Variation was observed in the nucleotide sequences of the Ibadan viruses HA genes. Some of the base changes resulted in amino acid changes which mapped to antigenic sites or within signal sequence in the HA1 domain as a result of a process of antigenic or genetic drift. The Ibadan viruses also showed some variation from the prototypic European virus (Suffolk/89) and these base changes also resulted in amino acid changes resulting in antigenic drift. Phytogenetic analysis showed the evolutionary lineages in equine H3 viruses isolated since 1963 along two paths one of which included the Ibadan viruses as well as viruses isolated in Europe between 1989 and 1991 and the Far East in 1992 and S. America in 1993 which form the 1989/93 cluster while the other lineage included viruses isolated in South America in 1987 and 1988 (Brazil/87, Laplata/88) and in the Far East in 1971 (Tokyo/3/71) all of which are very close to the original prototype equine-2 virus (Miami/63). These results demonstrate a faster evolutionary rate for recent equine H3 HA genes away from the original prototype virus. Overall, the results of these studies have (i) confirmed the occurrence of equine-2 H3N8 influenza viruses of distinct lineages in Nigerian equine populations in a tropical environment (ii) indicated antigenic drift among equine H3N8 viruses as earlier reported and confirmed that drift strains can co-circulate in equine populations, (iii) showed the origin, evolution and genetic relatedness of the viruses genes as well as their biological characteristics, (iv) provided the hitherto unavailable information on the status of equine influenza virus in this part of the world and (v) served to re-emphasise the potential of influenza virus for rapid global spread and the need for better control strategies. 1 results 1
- ANC accessibility 1 results 1
- African Culture 1 results 1
- An experiment was undertaken to determine the effect of boiling of cocoa pod husk and levels of inclusion that will positively affect the growth rate of Clarias gariepinus, a major species of importance cultured in Nigeria. Cocoa Pod husk is a by-product of cocoa industry often discarded as Waste. This study was to assess the effect of incorporation of boiled Cocoa pod husk into the diets of C .gariepinus juveniles. One hundred and thirty juvenile fish (3.35 g initial mean weight) were randomly allocated to five treatments each having two replicates. Two batches of cocoa pod husk were treated differently: the first batch was beaten to smaller pieces, sun dried and ground to fine powder, while the second batch was boiled for 30 minutes in water at100oC, sun dried and ground to fine powder. These were done in an attempt to reduce the anti nutritional factor, theobromine an alkaloid present in the CPH. The experimental diets consisted of 0% cocoa pod husk (control), 10% CPH (the best diet in a previous experiment), other treatment consisted of boiled cocoa pod husk at 10,15 and 20% levels of inclusion representing treatments 1 to 5 respectively. The experimental diets were formulated to contain 36% crude protein and fish were fed at 4% of their body weight thrice dally for 8 weeks. At the end of the trials the experimental diets were analyzed for their proximate composition, growth performance and nutrient utilization. From the result of the experiment, 10% of boiled CPH showed the best results (p<0.05) in terms of weight gain, protein efficiency ratio and feed intake of C. gariepinus juveniles. Therefore 10% inclusion of CPH was recommended for inclusion in diets of C. gariepinus juveniles. However further research should be carried out on other processing conditions of cocoa pod husk that will allow higher inclusion and efficient utilization by fish. 1 results 1
- Antenatal care 1 results 1
- Bacteria 1 results 1
- Blood composition 1 results 1
- Cellulose, 1 results 1
- Central -Fatness 1 results 1
- Christianity and Reproductive Technologies 1 results 1
- Clinical enzymes 1 results 1
- Context 1 results 1
- Coppicing 1 results 1
- Coppicing, 1 results 1
- Culture media 1 results 1
- Ex-situ conservation 1 results 1
- Feeding trial were conducted in experimental tanks (50 x 34 x 27 cm) to assess the growth responses and nutrient utilization of Walnut Leaf (WL) and Onion Bulb (OB) residues in Clarias gariepinus. Nine experimental diets: control (0%), OB2 (0.5%), OB3 (1.0%), OB4 (1.5%), OB5 (2.0%), WL6 (0.5%), WL7 (1.0%), WL8 (1.5%) and WL9 (2.0%) were formulated and replicated thrice at 40% crude protein. Fish (mean weight 7.39±0.02 g and length 10.37±1.24 cm) were fed twice daily at 3% body weight for 12 weeks. Mean Weight Gain (MWG), Specific Growth Rate (SGR) and Feed Conversion Ratio (FCR) were measured. Temperature, dissolved oxygen and pH were determined using standard methods and economic analysis was investigated. Data were analyzed using descriptive statistics and ANOVA at p=0.05. Results showed that the Fish on OB and WL residue- based diets had higher growth than those on control diet but C. gariepinus fed WL8 had significantly higher MWG, SGR and FCR of 53.81±1.20 g, 1.09±0.11 g and 2.16±0.01 respectively of all treatments. The values of temperature, dissolved oxygen and pH were closely related and were still within the range for fish culture in the tropics. WL8 had higher profit index (1.40) and incidence of cost (0.032) and the least in OB5 (1.18) (0.039) respectively. These suggest that walnut leaf residue at 1.5% inclusion could be a potential, less expensive and promising dietary supplementation than onion bulb residue and control that would positively affect growth and water quality of Clarias gariepinus in aquaculture 1 results 1
- Fertilizer application in earthen ponds has been used as a low-cost method of sustainable aquaculture production. This study was carried out to investigate the growth response of African catfish fry, Clarias gariepinus in three different culture media in homestead concrete tanks. The water in the control (T1) was not treated while T2 and T3 were treated with poultry droppings and soy bean milk filtrate, respectively. Nine hundred catfish fry weighing averagely 0.67-0.69 g were randomly allocated to the 3 treatments in equal number. In each tank (2x3x1.5 m) were suspended, 3 net cages each of dimension, 1x1x1 m containing 100 fry. The fish in tank 1 (control treatment) were fed fish meal from the start at 5% of their body weight and four times daily. The other treatments were not fed at all for the first 7 days. Feeding with fishmeal commenced for treatments T2 and T3 on the next 8-14 day. The weights of the feed were adjusted after weekly weighing of the culture media for phytoplankton composition. The best weight increase was recorded in T1 (2.33 g). The highest survival rate was in T3 (98%). Treatment T3 (11.56±1.14x103) generated higher concentrations of most of identified zooplanktons than treatments T1 (5.39±0.73x103) and T2 (12.78±0.98x103). These zooplanktons were absent in treatments T1 and T2. The result indicates that fertilizing the culture medium using soybean milk filtrate or poultry droppings improved the growth and of C. gariepinus. 1 results 1
- Giving birth to children is very important in many African societies, because children are portrayed as evidence of fruitfulness and blessings from God. In fact, there is a saying that children are the gains of a marriage. Amid this huge burden and societal expectations, some couples are encumbered with this weight as a result of some medical challenges in the area of procreation. Scientific advancements have offered interventions to mitigate this problem, as is evident in other human endeavors, where scientific solutions have come to the rescue through a number of reproductive technologies. Extant literature on human reproductive technology have focused largely on the procedures and ethical perspectives with scant attention paid to it from a Christian religious perspective. This study therefore, explored a religious justification of the role of science in human reproduction. This was with a view to addressing the concerns that have been raised by varying adherents of religions and schools of thought regarding the ethics of reproductive technologies. The aim of the study was to answer questions on whether reproductive technologies contravene the natural way of human reproduction and whether they tamper with the supremacy of God. The paper concludes that there is no justifiable reason for rejecting the gift of knowledge of God to humanity through science in the area of human reproduction using St. Augustine’s Concept of Knowledge that all human knowledge comes from God. 1 results 1
- Human Procreation 1 results 1
- In this study, the effect of walnut leaf (WL) and onion bulb (OB) residues on tissue bacteriology of Clarias gariepinus juveniles by dietary intake was investigated. Nine experimental diets: control (0%), OB2 (0.5%), OB3 (1.0%), OB4 (1.5%), OB5 (2.0%), WL6 (0.5%), WL7 (1.0%), WL8 (1.5%) and WL9 (2.0%) were formulated and replicated thrice at 40% crude protein. Fish (mean weight 7.4±0.02g) were fed twice daily at 3% body weight for 12 weeks. Microbiological analyses of water and fish (skin, gill, intestine and liver) and organ index (liver, spleen, kidney and heart) were investigated. Data were analysed using descriptive statistics and ANOVA at p=0.05. Results of enterobacteriacea and total viable count from this study revealed that bacterial loads on the water and fish of the experimental tanks were more affected by A. cepa and T. conophorum than the control for 4, 8 and 12 weeks and were significantly different (P<0.05) from the control. The values decreased in treated groups as the levels of inclusion (0.5%, 1.0%, 1.5% and 2.0%) increased and as the months increased. Also, organ index showed that the liver, heart, kidney and spleen were not significantly increased in all the treated groups and the control. The results suggest that walnut leaf and onion bulb residues inclusion in the diet of Clarias gariepinus could be a potential, less expensive and promising dietary supplementation that would positively influence growth, reduce and prevent bacterial infections in fish culture. 1 results 1
- In-vitro propagation 1 results 1
- Khaya grandifoliola 1 results 1
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