MST-Department of Zoological Sciences

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Immunization studies in rabbits using midgut membrane bound protein derived from rhipicephalis appendiculatus neumann, rhipicephalus evertsi evertsi neumann and amblyomma variegatum fabricius
(Kenyatta University, 1990) Kutima, Hellen Lydia
The objective of this study was to immunize rabbits with midgut membrane-bound proteins derived from partially engorged Rhipicephalus appendiculatus, R. evertsi evertsi and Amblyomma variegatum female ticks a~d assess whether the immunity elicited was protective against both homologous and heterologous tick ins tars and to isolate and identify the protective antigens. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of the Gut Membrane-Bound Protein (GMBP) antigens demonstrated protein bands with molecular weights ranging from 14 to 140 kDa. Approximately 37 protein bands were fractionated from appendiculatus GMBP antigens, approximately 45 protein bands ere fractionated from . evertsi evertsi GMBP antigens and approxi ately 39 protein bands were fractionated from !. variegatum GMBP antigens. Twentytwo of the isolated proteins were shared among the three tick species. The ability of rabbits to acquire resistance 'to ~. appendiculatus, R. evertsi evertsi and !. variegatum was determined by injecting three separate se~s of rabbits with respective GMBP antigens. Resistance was manifested by prolonged feeding, reduction in engorgement weights, egg mass weights, mou ting and percentage hatchability and increa ed mortality. Cross-resistance was evaluated by dividing R. appendiculatus, R. evertsi evertsi and A. variegatum resistant rabbits into three groups each and challenging them with homologous and heterologous live stages. Considerably high cross-resistance was apparent among the three groups. Cross-protection was more pronounced in the homologous than heterologous systems. Enzyme Linked Immunosorbent Assay. (ELISA) technique detected circulating antibodies in the immune sera to GMBP from homologous and heterologous systems one week after the primary dose. Ouchterlony double immunodiffusion reactions with anti-tick GMBP sera formed 2 to 4 precipitin lines with homologous GMBP antigens and 1 to 2 precipitin line(s) with each heterologous GMBP antigens. A line of complete identity was observed when immune sera to GMBP antigens reacted with GMBP from homologous and heterologous tick species, suggesting common antigenic epitopes. Western blot analysis on GMBP of R. appendiculatus, !. evertsi evertsi and !. variegatum with sera from immunized rabbits detected protein bands specific to the homologous GMBP antigens, and revealed considerable cross-reactions in the heterologous systems. In conclusion, there was prolonged feeding periods, reduced engorged weights, egg mass weights hatchability and moulting and increased death rate of both homologous and heterologous challenge ticks which fed on resistant rabbits. This was due to the presence of common antigens. The presence of cross-reacting antigens conferred cross-protection. These results have pointed out that it is possible to protect livestock from R. appendiculatus, R. evertsi evertsi and !. variegatum using an antigen from anyone of the three tick species hence reducing the expence of having to develop an antigen to control each tick species as there are in existence.
Heavy Metal and Organochlorine Pollutants in Tissues of Marine Fauna along the Coast of Mombasa Island - Kenya
(Kenyatta University, 2000) Kipkosgei, Bor Samuel
Marine pollution is increasingly becoming a problem along the Kenyan coast. Heavy metals and organochlorine pollutants have the potential to damage the delicate marine ecosystem with the result that the country's important foreign exchange earner - tourism - could seriously be affected. This study aimed at assessing the levels of cadmium, lead, copper, zinc, manganese, iron and titanium using Energy Dispersive X-ray Fluorescene (EDXRF) and Atomic Absorption Spectroscopy (AAS) in selected marine fauna. It further assessed the levels of lindane, aldrin, dieldrin, endosulfan (o-, B-), DDT and its metabolites using Gas-Liquid Chromatographic (GLC) techniques. Certified reference material (Mussel Tissue, MA-M-2ITM, IAEA) was analyzed by, both AAS and EDXRF techniques, for quality assurance and control. The two methods are in good agreement and the results are within 10% of the certified values (Appendix III). For statistical analysis, regression analysis was used to calculate the concentration of samples and relationship between pollutant concentrations. Some of the calculations refer to the dry weight of soft tissues. One-way analysis of variance (ANOVA) was applied with the aid of a computer programme to investicate the differences in pollutant concentrations between animal samples and between locations. The level of statistical significance was set at p::;0.05, unless otherwise stated. Tukey's studentized range test was used to separete the means when ANOVA indicated significant differences. Marine animals used for the study were chosen from molluscs, echinoderms, crustaceans and chordates sampled mainly along thexiii coast of Mombasa Island. Some samples were also collected from Vanga in the South Coast, Nyali Beach and Marine Park in the north. The four groups of animals were all found to have accumulated heavy metals and pesticides to some considerable extent. Concentrations of lead and cadmium ranged from 3.68 - 5.70 ppm and 0.47 - 1.45 ppm respectively. Pesticide levels were, however, relatively low (0.227 ± 0.026 ppm ). Lindane which was found in 64% of all the animals studied, ranged from the detection limit (0.01 ppm) - 0.561 ppm. Marine fauna sampled near the Mombasa showground (English Point) contained higher than average (4.25±0.37 ppm against a mean value of 2.295±0.22 ppm) levels of the heavy metals studied. Pesticide concentraion had a similar pattern with a level of 0.383±0.039 ppm against a mean value of 0.235±0.039 ppm. Vanga was another place where marine animals were found to have accumulated the heavy metals and pesticides to a significant (p = 0.0481) extent (4.07±0.25 ppm and 0.242±0.01 pprn respectively). The highest concentration of lead (14.80 ± 0.42 ppm ), recorded in this study was found in Crassostrea sp. sampled from Vanga. Cadmium registered a concentration of 3.49 ± 0.31 ppm in Uca vocans collected from Mbaraki. The same species registered the highest concentration of lindane ( 0.561±0.5 ppm ). Although this study has confirmed that marine fauna from the Kenyan Coast have accumulated both the heavy metals and pesticides studied, the levels are generally low compared to the results from a similar study by Windom (1991). However, unless the pollutants are monitored continuously, the levels are set to increase, with serious implications.
The Effect of Changed Health Care Financing on Levels of Malaria Specific Morbidity Andmortality in Kericho District, Kenya.
(Kenyatta University, 2002-04) Kipkorir, Florence C.
Malaria has remained the main cause of morbidity and mortality over the last twenty years contributing to about 40% of all illnesses in Kenya. The increasing resurgence and severity of malaria is not well understood. Global warming and vector conquest of hitherto malaria-free Highlands of Kenya could be contributing factors, but it is difficult to ignore the possible contribution of changed health care financing (cost sharing) to malaria resurgence and increased mortality. This study was aimed at establishing the possible effects of cost sharing on levels of malaria morbidity and mortality in Kericho District. Kericho district has a large population of relatively poor people and malaria is endemic in its lowlands and experiences epidemics in the highlands. The introduction of structural adjustment programmes including cost-sharing (user charges) in health facilities could have a devastating impact on the poor members of this community with consequent exacerbation of malaria related morbidity and mortality. This is because the effect of price demand for health services is higher for low-income groups than in high-income groups The results from Hospital records questionnaires and focus group discussions showed that malaria was leading among the top ten diseases in the district, and was the main cause of the disease burden in Kericho District. The majority of the study subjects (74.2%) lived within 4kms from the nearest health facility and yet attended the health facility infrequently when sick. The reasons given for irregular attendance was lack of finance in (50.7.6%) or lack of medical facilities (30.5%). The introduction of user charges contributed to less use of medical services as given by 69.1% of study subject resulting in delay in seeking health care as a response to the XII introduction of userchrges. The study subjects who opted to go for cheaper over the counter drugs that were probably not effective against malaria infection were 87.5%, this may have lead to admission of more severe cases of malaria in the health facilities subsequent to the introduction of user charges. The information from this study is useful in designing malaria control programmes aimed at reducing morbidity and mortality and related economic losses associated with human malaria in the study area and elsewhere in Kenya. The study on the effects of user charges on malaria morbidity and mortality is second to none and it forms a base for future researches on effects of introduction of usercharges in Government health facilities, especially on the poor in malaria endemic areas of Kenya.
Determinants of non-use of family planning among married women in Kabati Division Kitui District, Kenya
(2002-06) Thuo, Julia Waithira
Family Planning (FP) is one of the most important interventions in health care. As the demand for reproductive health care grows, advocacy for Family Planning is becoming crucial. Yet and inspite of the efforts towards fertility control, there remains a substantial proportion of women in reproductive age-group who are not using Family Planning methods even though they do not want a pregnancy right away. A cross-sectional descriptive population-based study was conducted to determine the reasons for the discrepancy between fertility preferences and contraceptive practice in Kabati division, Kitui district. A total of 450 married women in reproductive age (15-49 years) were interviewed using a structured questionnaire in addition four focus group discussions (FGDs). The results indicated that majority of the women 281 (62%) did not use any contraceptives (non-users) and only 169 (38%) were users. Majority 320 (71%) of the respondents were aged between 25-39 years. Most respondents aged 15-19 years and 44-49 years were non-users and age-gr~mp 25-29 years had a high number of non-users 88 (60%). In terms of religion, the respondents were mainly of Protestant faith j 254 (56%) but most Catholics 131 (68%) were non-users compared to 147 (58%) Protestants non-users (X2 = 5.02, P = 0.02). Majority 251 (58%) of the women had attained primary level of education with 163 (65%) being Family planning non-users (x2 = 17.98, P = 0.00044). Similarly, most respondents 363 (81%) were housewives and majority 240 (66%) were non-users while among the professionals the users were the majority 20 (65%) (X2 = 16.2, P = 0.0003). On account of more children, most 274 (60%) women did not intend to have more children and majority 160 (58%) were (vi) non-users. Economic reasons were cited by half of the respondents 140 (51%) as the main reason for non-intention to have more children. Most 153 (54%) non-users had inadequate knowledge of Family Planning while most users 96 (57%) had adequate knowledge. A total of 163 (36%) respondents did not discuss Family Planning issues with their spouse. Among these, 119 (73%) were nonusers compared to only 44 (27%) users (X2 = 12.15, P = 0.0001). The nearest health facilitywas reported to be the health centre and most respondents, 281 (62%) lived a distance of more than 5 km from the nearest facility and only 3 (2%) obtained Family Planning methods from the Community Base
Effects of land-cover dynamics on the foraging ecology of amboseli yellow baboons (papio cynocephalus, linnaeus 1766)
(Kenyatta University, 2003) Oremo, David Walter Odede
The status of land-cover is of prime concern to spatial ecologists and wildlife conservationists. This study used Geographic Information Systems (GIS) to analyze land-cover changes that have characterised the Amboseli basin, situated in southern Kenya, over a 16-year period. The land-cover maps of 1984 and 2000 were derived from Landsat Thematic Mapper (TM) images at spatial resolution of 900 m2. Automated digital image processing and segmentation techniques were used to delineate the mapping units corresponding to twelve prior defined landcover types. The dynamics were compared using the mean number, size, perimeter and fractal dimension of patches. The conservation significance of the maps is illustrated by evaluating the effects of the land-cover dynamics on foraging ecology of Amboseli yellow baboons (Papio cynocephalus). The results indicate that significant transition was evident in eight landcover types that accounted for about 68 per cent of the study area. The study groups shift their ranging area to the southwestern portion of the basin. The baboons significantly changed their feeding time budget, increasing the time allocated to feeding. Significant differences were observed between the groups in the time spent feeding and mean daily distance travelled. Alto's, the largest group, spent more .time feeding and travelled the greatest distance in both study years. The ranging size and pattern was dependent on the group size. The results also suggest that information sharing may be one of the prime benefits of living in larger groups for this population. The results are suitable for land-use management applications in the Amboseli basin and baboon habitat suitability modelling,
Population Dynamics and Habitat Use by Murid Rodents in Maize Cropping Systems in Rongai Division, Nakuru District, Kenya
(Kenyatta University, 2003) Odhiambo, C.
Murid rodents are an important pest group in eastern African agriculture by causing crop depredation, and as reservoirs for epizoonotic infections. On a global scale, they also pose some of the most complex management problems leading to huge capital expenditures towards their control. Gaps in our knowledge of how to plan for effective control need ecological theory and field data to provide vital ingredients in the design of sustainable management strategies. Efforts to obtain such information have gathered momentum especially in southeast Asia and Tanzania. Relatively less work has been done in Kenya and information lacking includes long-term ecological studies of pest species in cropping systems. This study, therefore, aimed at providing information towards bridging this gap. In order to achieve the above-mentioned goal, I set to investigate the demographic patterns and habitat use by murid rodents in maize cropping systems between May 2000 and December 2001. Capture Mark Recapture (CMR) technique was used on four permanent one-ha square grids established along an altitudinal gradient. Rodents were captured using Sherman's live traps placed at 10m spacing between trapping stations. Traps were baited with fried coconut cubes mixed with peanut butter and Elianto cooking oil. A total of 1240 captures including recaptures of 837 individuals were made of rodents and shrews in 20,100 trap nights. Fifty-three animals were found dead in the traps during handling. The rodents included six murid rat species (Aethomys cf kaiseri Noack 1887, Arvicanthis cf neumanni 1822, Lemniscomys striatus Linnaeus 1758, Mastomys cf erythroleucus Smith 1834, Rattus rattus and Mus minutoides Smith 1834) and a cricetid (Tatera cf. robusta Cretzschmar 1830) while the shrews were all soricids (Crocidura species). Mastomys was the dominant species within and across grids, accounting for 71.0 % of all captures. Other common rodents were Arvicanthis (14.1 %) and Mus (8.0 %). The other species represented less than five percent of captures, with Aethomys being represented by three individuals and Rattus by one. Aethomys and Rattus were captured only at the Mugo grid located at highest altitude (1922m ASL) while Tatera was restricted to lowest altitude (1712m) at the Moto grid. Small mammal species diversity was highest at Mugos (D=2.411 and H'=1.639) and least at Kurt's (D=1.333 and H'=0.829). Rodent species equitability was highest at Moto grid (E lID = 0.586) and least at Beth's (E IID = 0.266). Beth was closer to Kurt in terms of species assemblages, while Mugo and Moto grids were least similar. Rodent population densities showed similar dynamics, with most captures being made towards the end of the cropping season. Density fluctuations were low but influenced by the distribution of annual rainfall. Mastomys cf. erythroleucus population structure changed over time. Age distribution was influenced by the amount of precipitation. Sex ratio was of the expected 1:1 ratio with exception of a few months. The overall body mass dynamics showed no sexual dimorphism between males and females. Seasonal variations had strong effect on body mass dynamics (F = 14.268, P = 0.0004, n = 48), and field growth rates (F = 8.791, P = 0.005, n = 58). Larger individuals and higher growth rates were recorded during the wetter seasons. Population density did not have any significant effect on body mass dynamics or field growth rates. Breeding in Mastomys was depressed by drought but when there was adequate distribution of rainfall throughout the year, reproductively active individuals were encountered in all the months. The first breeding commenced following 100mm of rainfall between May and June 2000. The second followed 332mm of rainfall In November 2000 and January 2001, leading changes in population structure and subsequent increase in population densities. Heterogeneity in recruitment and survival occurring between sexes and age classes across grids were perhaps influenced by rainfall distribution. Maturation rates were low (mean ± SEM: 0.113 ± 0.029 males and 0.156 ± 0.035 females), respectively Rodents exhibited very low population persistence with individuals staying in an area for an average of 37 ± 1.635 days. Male and female Mastomys cf erythroleucus showed similar range lengths. However, between any given trapping period, males exhibited wider range distances than females. There was significant seasonality in range lengths with animals covering longer distances during wet than dry conditions. Distribution of rodents was aggregated at the edge of the farms. Ground cover had stronger influence than habitat structure on capture frequency of rodents. This study has documented the presence of seven rodent species with potential pest statuses in maize cropping systems of Rongai Division, Kenya. Mastomys, a multimammate rat, was the most important species due to numerical dominance in all the maize crop fields. Multimammate rats are recognised across Africa as important pests of crops and as disease reserviors. The prolonged drought occurring in two consecutive years prior to the commencement of the study led to low rodent numbers in the area. Population recovery was noted towards the end of the first cropping season. This suggests higher growth rates may occur during unusually higher rainfall leading to population outbreaks. The strong association between rodent captures and patches of dense weed cover reiterate the importance of cover removal as a strategy in ecologically based rodent pest management. Rodents were also captured largely along farm edges, and crops at these points are likely to get damaged. Field edges may therefore be important target areas during chemical control operations. This study has contributed vital though not exhaustive information on rodent population ecology in maize crop fields, which is important in designing ecologically based rodent pest management for Kenya.
Impact and factors associated with gastro-intestinal parasitic infections among pupils in Thika District, Kenya
(Kenyatta University, 2009) Ngonjo, Teresia Wambui; Gicheru, M. M.
Intestinal parasitic infections are amongst the most common human infections worldwide. It is estimated that some 3.5 billion people are affected, and that 450 million are ill as a result of these infections, the majority being children. These parasites remain a major health problem in many developing countries. The study set out to investigate the factors that influence intestinal parasitic infections and their effect on growth status of school going children. The study was conducted in four public primary schools namely, Athena (peri-urban), Kathambara (rural), Kianjau (slum) and St.Patrick (urban) aU in Thika district, Kenya. The stools were collected from children and examined for helminthiasis by kato-katz technique. Protozoa were examined using formol ether concentration method and fresh saline smears. Anthropometric measurements of weight and height of subjects were taken to determine the relationships of intestinal parasitic burden and degree of stunting, wasting and malnutrition. Information on family background of the study subjects was obtained through a standard pre-tested questionnaire. Chi square and one way Anova tests were used for comparing infection by sex, age, the risk factors of intestinal parasitic diseases and to compare mean heights and weights between children in the four schools. Prevalence of intestinal helminthes in children of peri-urban, rural, slum and urban schools were 38.9%, 48.9%, 48.9% and 31% respectively. Prevalence of intestinal protozoa of pupils in peri-urban, rural, slum and urban schools were 46.3%, 38.9%, 34.8% and 28.7% respectively. Ascaris lumbricoides infection was significantly higher in slum and rural than in peri-urban and urban schools (x,2=14.425, df=3, p<0.05). Hookworm infection was significantly higher in the rural and peri-urban schools than in urban and slum schools (r-15268, df=3, p
Performance of Dynabead Technique Compared to Facs Techniques in Enumeration of cd4+ tcells in HIV Positive Patients Attending Mbagathi Hospital, Nairobi
(2009-04) Maina, T.N.
Human immuno-deficiency virus and Acquired Immune Deficiency. Syndrome (HIV and AIDS) is a major public health problem, a socio-economic burden and a serious threat to development particularly in developing countries. Human Immunodeficiency Virus (HIV) causes progressive impairment of the body's immune system, increased susceptibility to infections, tumors and Acquired Immune Deficiency Syndrome (AIDS). Enumeration of CD4+ T cells evaluates the strength of the immune system and is crucial in monitoring of HIV infected persons, as it is the best indicator of immuno-suppression. Flow cytometry (FACS count) is the accepted gold standard method for CD4+T cell counting. However the cost of the equipment and reagents of FACS count is often unaffordable for routine use in resource limited settings. This study evaluated the application of Dynabead technique using a light microscope for CD4 enumeration on HIV positive patients. Fifty four (54) EDTA blood samples from HIV positive patients attending Mbagathi District Hospital care clinic were used in the study. Parallel CD4+ T cell count was carried out using BD FACS count and Dynabead techniques. The sensitivity, specificity, positive and negative predictive values of Dynabead technique was determined using a 2x2 table. Precision of Dynabead technique, as well as the effect of delay in sample handling was also determined. The results of the study revealed that CD4+ T cell counts by FACS count and Dynabead technique were highly correlated r= 0.962, p0.05). The sensitivity and specificity of Dynabead technique at clinically relevant CD4+Tcell count (200 cell/ul of blood) was 87.5% and 96.7% respectively. The coefficient of variation for the precision of Dynabead technique varied between 3.4% and 7.5%. CD4+T cell count by Dynabead technique on fresh and four days old blood revealed a significant difference (t=8.694, df =53, p<0.05).The results showed that Dynabead technique is comparable to FACS count in CD4+ T cell enumeration on fresh blood sample and therefore can be used as a reasonable substitute to FACS count in resource constrained areas in Kenya. However it was also noted that Dynabead technique was not accurate in CD4 enumeration for samples that had been preserved for four days at room temperature. It is recommended that Dynabead technique be adopted as a method for CD4+ T cell enumeration in resource constrained areas in Kenya.
Evaluation of selected medicinal plants for chemotherapeutic Activities on plasmodium knowlesi and plasmodium berghei
(Kenyatta University, 2010) Were, Patrick Simiyu
Malaria is one of the most widespread haemoparasitic diseases in the world, with an estimated incidence of about 500 million clinical cases annually and a corresponding annual mortality of up to 2.7 million. The use of conventional antimalarial drugs as a control strategy for malaria is greatly hampered by drug resistance exhibited by the parasites. Moreover, about 75% of the population in Africa does not have access to conventional medicine and therefore resort to traditional medicine (TM) for treating the disease. These TM suffer from lack of objective diagnosis and paucity of information on pharrnacokinetic factors such as formulation, toxicity, dosage forms and efficacy. Among the Kenyan communities living around Ngong Division of Kajiado District, malaria is a common problem and has been culturally treated using TM. This study was therefore carried out to determine the efficacy of four selected medicinal plants from Oloolua Forest, Ngong Division, popularly used by local herbalists in treating malaria. A total of 15 crude extracts were prepared from Warburgia ugandensis, Zanthoxylum usambarense, Aloe ngongensis and Ajuga remota and assayed for in vitro activities against Plasmodium berghei and P. knowlesi. Extracts that displayed high activities were subsequently assayed for curative and prophylactic activities against P. berghei using the four-day suppressive test in BALB/c mice. A total of 40 male adult mice were used in the two regimens in which experimental mice were treated with each extract at a dose rate of 200mg/kg/day being administered intraperitoneally, while control groups received Phosphate-Buffered Saline at the same rate. Mean parasitaemia inhibitions and survivorship values were reported as means ± SEM and compared using one-way analysis of variance (ANOVA) and the student t-test. All p-values less than 0.05 were considered statistically significant. Significant reductions in parasitaemia levels from in vitro tests (4 = 19.84,p < 0.05) were observed in treated groups relative to the controls. Three extracts; chloroformic and methanolic from W ugandensis and aqueous extraction of Z usambarense displayed significantly high parasitaemia suppression in chemotherapeutic (F = 9.63, df = 3, 15,P < 0.05) and chemoprophylactic (F = 5.812, df = 3, 15, P < 0.05) assays respectively. The most effective chemotherapeutic agent was the chloroformic extract with an average parasitaemia suppression of 69%. On the other hand, the most active prophylactic agent was found to be an aqueous extract from W ugandensis that produced 67% suppression of parasites in BALB/c mice. The same extract was equally therapeutic, giving a suppressive value of 65%. In terms of mice survivorship, the aqueous extract from Z usambarense as well as both methanolic and chioroformic extracts from W ugandensis significantly increased mean survival times (MST) in treated groups in both therapeutic (F = 40.462, df= 3, 10,p < 0.000) and prophylactic analyses (F = 67.74, df= 3, 10, p < 0.000). The results indicate that W ugandensis and Z usambarense possess bioactive antiplasmodial compounds. On the basis of this study, it is recommended that bioactive substances from W ugandensis and Z usambarense should be identified and characterized as prime candidates for novel antimalarial drugs
Farmers' knowledge, effect of their practices and soil amendments in the management of sweetpotato pests in southwestern Kenya.
(2011-05-08) Kababu, Orengo Margaret
Sweetpotato is a major food security crop grown in Kenya. Its production is however limited due to high prevalence of pests and diseases among other factors. Cultural control appears to be the most promising strategy in curbing this problem. However, the recommended cultural control practices are based on farming practices in Asia and United States of America that may not be appropriate for subsistence farmers found in Kenya. This study sought to establish farmers' knowledge on sweetpotato pests and their practices in the management of these pests in Southwestern Kenya; taking into account the socialcultural, socialeconomic and biophysical factors affecting sweetpotato production. It also sought to establish the effects of soil ammendments on the diversity and abundance of soil-dwelling predatory arthropods which could be effective in the management of sweetpotato pests. Farmer based data was obtained using a semi structured questionnaire administered to a total of seventy five farmers. An experimental plot was set up in Rongo District with four treatments in four replications to establish the effects of soil amendments included animal based manure, plant based manure, inorganic fertiliizer and control. The outcome of the study indicated that farmers had limited knowledge on sweetpotato pests and did not carry out any methods of control against them. Sweetpotato production was basically left to women and the crop came second to maize. The major constraints to production included moles, hippos, hard labour, insect pest and diseases, costly transport, low selling prices and lack of storage mechanisms. Shannon Weiner diversity and species richness and evenness revealed that the greatest diversity and abundance of predatory arthropod species occurred in the control plot where no ammendments was used. The control plot also recorded the highest percentage of both marketable and undamaged tubers through not significantly so. The least diversity and abundance of species was recorded in amendments with animal based manure whereas the least percentage of both marketable and undamaged tubers was recorded in amendment with inorganic fertilizer. This may imply that no amendments were actually required to enhance the diversity and abundance of ground dwelling predatory arthropods. Berger-parker dominance index indicated that species were more dominant in the amendments with inorganic fertilizer whereas Sorensen's similarity index revealed that the greatest similarity of species occured between the amendments with plant based and animal based manure. The efficacy of the predatory arthropods in the management in enhancing the crop's resistance to sweetpotato pests could also not be ascertained within the scope of this study.
The impact of free primary education of internal efficiency in Londiani Division, Kipkelion District, Kenya
(2011-05-08) Khamala, Nekesa Rose
This study investigated the impact of Free Primary Education (FPE) on internal efficiency of public primary schools in Londiani Division of Kipkelion District. It is a well-known fact that education plays an important role in national development by equipping people with skills that improve their productive capacities. Primary education is particularly known to have a high social benefit, which is why the government of Kenya has been committed to the attainment of its national objective of providing universal primary education to all school- age children. The government's commitment can clearly be seen through the introduction of FPE in 2003, which saw enrolments surging from about 6 million to about 7.6 million by 2006. Unfortunately, cases of dropout and absenteeism still affect schools in Londiani Division, as is the case in other parts of the country. The objectives of the study were to determine the rates of enrolment, dropout and the patterns of absenteeism and the factors responsible for the rates and patterns so identified. The researcher also established the immediate short to medium term outcomes on acquisition and utilization of teaching learning resources, including any constraints faced by the administration in running the schools. This study was anticipated to be of immense significance to the police makers in building corrective measures to ensure optimal provision of FPE. The study adopted descriptive survey design. Stratified random sampling was used to sample out nine (9) schools from a total of 41 schools. The researcher used two questionnaires which were issued to head teachers and class teachers of the selected schools. The reliability of the questionnaires was established by piloting the instruments in one school. This reliability was tested using the split-half method. The data collected were analysed using descriptive statistics with the help of SPSS. This involved computation of modes, and percentages. Data were presented descriptively using charts, frequency distribution tables and graphs. The findings of the study show that after the introduction of FPE enrolment in all schools went up in all classes. However, dropout cases started to rise after two or three years. Besides, there were many overage pupils who enrolled. The main factors which contributed to dropout and absenteeism included repeating classes, domestic chores, overage and underage, poverty, parental negligence, drugs and circumcision rites. Many schools had inadequate teaching staff, inadequate desks and toilets but the textbook-pupil sharing ratio was very good at an average of 1:2 in all the subjects except Social Studies. Besides, indiscipline of pupils and congestion in classrooms were also major constraints faced by teachers during the teaching-learning process. The researcher recommends that the government should look into other contributory factors to dropout and absenteeism other than fee payment. Also, schools and the Government should devise ways and resources to accommodate the overage pupils, sensitise the parents on the importance of educating their children and generate more funds from other sources to expand school facilities.
Establishment of reference ranges of CD3 CD4 and CD8 lymphocyte subsets among healthy Kenyans
(2011-07-26) Bosire, Maosa Erick; Gicheru, M. M.; Khamadi, S
Flow cytometric analysis of peripheral blood lymphocyte phenotypes Iike CD4 and CD8 has proven to be useful in managing a wide range of medical conditions, including autoimmunity, immunodeficiency, infection, malignancy, and transplantation. Essential to the effective application of this approach is availability of accurate reference values against which results can be meaningfully compared. Reference ranges may be influenced by among other factors, age, gender, race, geographical area and social factors. Normal CD4 and CD8 reference ranges for both children and adults in Kenya have not been comprehensively established. Reference ranges that are currently used in Kenya are derived from data that mainly refer to Caucasian subjects who are not Kenyan The aim of this study was to establish the reference ranges for lymphocyte subsets name]', CD3, CD4 and CD8 among healthy Kenyans. Healthy blood donors of varied ages from different regions (Nairobi, Coast, Rift valley Eastern highlands and Lake Victoria bash) of the country were recruited into this study. Cluster sampling was used to collect samples from the different regions. Serological tests were used to confirm HIV and Hepatitis ,status of the subjects. Blood was collected by venipuncture into EDTA BD vacutainer blood collection tubes. Anti-coagulated blood stained with monoclonal antibodies (CD4/CD8/CD45) was analyzed by flow cytometry. BD FACS Calibur flow cytometer which has a sample loader was used. The FACS caliber provided CD3, CD4 and CD8 absolute counts, ratios and percentages. Analysis of these immune markers was made with reference to age, sex and geographical region. Results are expressed as median values with 95% double sided reference intervals. Reference ranges for the lymphocyte subsets were determined as pooled ranges. The 95th - percentile reference ranges were determined by using 2.5 and 97.5 percentiles. The general, 95% ranges for the whole study population were as follows CD3 (426.3992-3133.832), CD4 (228-1758.96), and CD8 (123.8997-1374.168). Significant differences were observed in the absolute count means of the lymphocytes in males and females than is CD3 (P<0.05) and CD4 (P<0.05). There were however no significant differences in the mean absolute counts between males and females (P<0.05). In females the means were CD3 (1787.1), CD4 (1009.8), CD8 (658.9) whereas in males the means were CD3 (1609.5), CD4 (888.9) and CD8 (644.1). Differences were also observed in the means and medians of the lymphocyte subsets in the different ages although the differences were not significance (P<0.05). The mean absolute counts for the different geographical regions were significantly different (P<0.05).The ranges that have been developed are different from the ranges that have been established by studies in other populations. These ranges are slightly lower than those of multiset (CD3 (690-2540), CD4 (410-1590) and CD8 (190-1140) and those developed in Germany (CD3 (780-2240) and CD4 490-1640). The ranges were close to the ones established in Tanzania that is CD4 (312.2-1367.6) and CD8 (168.2-1)96.8). These data can serve as reference ranges for adults in Kenya. Therefore the current guidelines on the normal CD4 and CD8 in Kenya should be revised to adopt the population specific reference ranges.
Impact of Longhorn beetles on the growth and survival of prosopis juliflora in Bura irrigation scheme, Kenya
(2011-08-01) Kariuki, Gicheru Naftal; Kairu, E. W.; Mbugua, Paul Kamau
Prosopis juliflora has been rated one of the world's top 100 unwanted species because of its invasive nature. In Kenya some of the negative effects of P. juliflora include invasion of farmlands, pastureland and water ways. The high cost and poor success of mechanical and chemical eradication techniques have led to the search of an appropriate biological control agent. In Kenya there is no known biological control agent for P. juliflora. However, casual observation in Bura showed Prosopis trees drying up as a result of beetle's infestation. This project therefore aimed at identifying the beetles feeding on the P. juliflora and assessing the extent of their damage. Beetle samples were collected from 365 trees and identified at National Museum of Kenya. Identification was achieved through morphological appearances and measurement of body parts such as pronotum, elytra length, antennal length and body length as compared to type specimens at Museum. The extent of damage on P. juliflora was assessed by correlating percent dryness observed in P. juliflora and estimated percent damage. Results showed that the beetles belonged to the longhorn beetles, 7aurotagus griseus. The beetles exerted significant damage on P. juliflora accounting for over 12.6% of Prosopis death in the study area. These results suggest that T. griseus can contribute significantly to the biological control of P. juliflora. However, further research is needed to determine the main factor(s) that influence T. griseus population dynamics, its host-seeking behavior and its effectiveness both in the lab and in the field.
Evaluation of the adjuvanticity of artemisinin with soluble leishmania major antigen in balb/c mice.
(2011-08-02) Kimutai, Albert
Leishmania moor is an obligate intracellular protozoan parasite that causes chronic cutaneous lesions that often result in disfiguring scars. Artemisilin, a well known antimalarial drug, has been shown to be efficacious against Leishmania ;parasites both in vivo and in vitro. This study sought to determine the adjuvant potential of arten,''isinin when administered with a soluble leishmanial antigen. To test this hypothesis seventy-two female BALB/c mice were randomly assigned into six treatment groups. The mice were vaccinated with soluble Leishmania antigens (SLA) alone, artemisinin co-administc red with SLA, SLA and Bacille Calmette Guerin (BCG) vaccine and artemisinin alone on clay 0 and boosted on day 13, then challenged with Leishmania major metacyclic promastigotes a week later. Unvaccinated mice formed the control group. The induction of cell-inediated immunity following vaccination was determined by measuring ex vivo lymphocyte proliferation and the production of interleukin (IL)-4, IL-5 and interferon gamma (IFN-y) determined by flow cytometry. Mice receiving SLA plus artemisinin produced significantl\ high levels of IL-4 and IL-5 (P<0.05) and levels of IFN-y level that did not differ significantly from those of the unvaccinated mice (P>0.05). Protection against L. major was determined by quantifying parasite burdens in L. major infected footpads using a limiting dilution assay and by measuring lesion sizes of the infected footpad as compared to the collateral uninfected footpad. Subcutaneous administration of SLA + artemisinin, artemisinin alone or SLA alone resulted in the development of large footpad swellings and high parasite loads that were comparable to those of the unvaccinated mice (P>0.05), resulting in exacerbated disease. These data suggest that artemisinin is not a suitable adjuvant for Leishmania vaccines. However, since artemisinin has been shown to be effective against Lei.shunania parasites in vitro and in vivo, further studies ought to be conducted to determine its immunochemotherapeutic potential when administered with Leishmania antigens.
Developing models for studying fish taxa composition and size selection using bones obtained from otter (mustelidae) scats in Kenya
(2011-08-08) Muriuki, Wambui Caroline; Ogol, C.K.P.O.; Thomas L. S.
The study of otters and their diet has been highly dependent on scat analyses because they are reclusive animals, very difficult to observe in the field Otters are largely opportunistic fish predators, but their diet may change depending on the changes in the availability of prey in their environment. However, mere identification of prey species is not sufficient. There is need for additional information on the size of prey inorder to determine whether there is spatial or temporal selection and variations of prey sizes. Most of the studies done to date have made use of scales, cranial and post-cranial skeleton, otolith and vertebrae retrieved from scats to back-calculate the size of fish consumed by otters. This study adopted a similar technique to develope models for studying the fish taxa and size selection by otters using opercular bones (opercle, cleithrum, preopercle and palatin) retrieved from otters scats obtained from Lake Victoria (Rusinga island, Dunga beach, Ndere island) and lower Ewaso Nyiro river (Mpala), and also investigate the dynamics in the otter diet composition. A total of 300 scats samples were collected and analysed between January 2006 and September 2007. The relative importance of various prey items in the diet was estimated using the frequency of occurrence analysis which showed variations corresponding to the availability of prey in the different sampling sites. Spotted-necked otter (Lrara maculicollis) scats from Rusinga were dominated by fish (86.60, while those from Dunga and Ndere were dominated by crab remains (94.4% and 100% respectively). Cape clawless otter (Aonyx capensis) scats analysis indicates presence of fish (67.30, crayfish (89.80 and crab (3.1%). However, the presence of crab disappeared towards the end of the sampling period and the diet was dominated by fish and crayfish in almost equal proportions. This shows that otters switch their prey according to availability and abundance within their home ranges. Three main fish taxa were considered in this study based on the ability to identify them in scats from their opercular bone structures that were used to develop models. Whole fish samples from the study sites were dissected and their opercular bones dimensions used to establish a relationship with the standard length expressed as: y - a + /Ix. The Selection of morphological features used in the models was based on the width of information that could be obtained per bone, and the level of error in the measurements. The best predictor models were selected based on the strength of the coefficient of determination (r) value. A total of 28 regression equation models were obtained for the relationship between different morphometric dimensions of diagnostic bones and standard length of fish. All regressions models were highly significant (P< 0.0001) and all gave coefficients of determination (r) between 66.4% and 99.1%. The best predictor model for Cichlidae was sub-opercle bone (4A; SL--3.73+ 14.76x; r2 =-92.80, Lates niloticus was pre-opercle (2C; ST- 2.84-t-7.31x; r2-99.1%), and Cyprinidae was (3A; 7.98 8.78x; r2 _ 90.4%). Results showed that Spotted necked otters select cichlidae and bates niloticus fish of approximate maximum total length 21.91cm and 50.29cm respectively. Cape clawless otters select fish of cichlidae and cyprinidae approximate maximum total length 14.09cm and 11.91cm respectively. This study found that scat analysis is useful in constructing a basic description of otter diet particularly when other methods are difficult or when one needs background information for planning broader studies of behavioral ecology.
Comparative in vitro study of quantitative and qualitative characteristics of free surface respiration macrophages in duck and the rabbit
(2011-08-09) Mutua, P. M.
In mammals, the surface respiratory macrophages (SM) play a critical role in protecting the respiratory system by providing first line defense through engulfing and destroying inhaled pathogens and harmful particulates. During adaptive immune responses, SM process and present antigens to T lymphocytes. Paucity of SM has been reported in the avian respiratory system. It has been reported that the pulmonary cellular defenses in birds are inadequate. In particular susceptibility to respiratory diseases in domestic birds has been associated with dearth of SM on the lung air sac system. In view of the protective roles SM perform in the respiratory system of mammals, the objective of the current study was to carry out a comparative in vitro study of the quantitative and qualitative characteristics of the avian and the mammalian SM by determining the number and the phagocytic capacity of the SM. The domestic duck was used as the avian model while the domestic rabbit was used as the mammalian model. Seven rabbits and seven ducks were subjected to respiratory lavage for recovery of SM which were quantified using hemocytometer and co-cultured with polystyrene particles in a culture medium for determination of phagocytic capacities. Morphologic, viability and mophometric studies of the SM were characterized at light and electron microscopy. Morphologically, the duck and the rabbit SM were similar. The SM had eccentric nuclei, cytoplasmic vacuoles and the plasma membrane had filopodial extensions. Quantitatively, the SM recovered by lavage of the ducks were fewer than the SM recovered from the rabbits. With a mean number of 1.5 x 107 SM recovered, the rabbits had significantly (p<0.05) more SM than the ducks whose mean number of SM recovered by lavage was 1.1 x 106. In the rabbits, the mean number of SM decreased steadily with progressive lavages. In the ducks, there was influx of SM indicated by significant (p<0.05) increase of the mean number of SM recovered during the first three lavages. Moiphometric observations revealed that the duck and the rabbit SM had equivalent diameters of 12 pm and 13 pm respectively. However, the duck SM exhibited a significantly (p<0.05) higher phagocytic capacity by engulfing substantially more particles at 20 % than the rabbit SM at 9 %. The higher in vitro phagocytie capacity and the influx of the duck SM are two important properties that can be exploited in vaccine development. Vaccine delivery by aerosolization should focus on the ability to promote influx of SM onto avian lung-air sac system without compromising the phagocytic ability of the cells. This is an area that should be exploited in prevention and management of avian diseases.
Cross-mating and oviposition behaviour between strains of cotesia sesamiae. cameron (hymenoptera: braconidae) from Kitale, Mombasa and MountKenya.
(2011-08-09) Ndegi, Mugambi Jane; Kairu, E. W.; Bruno, Le Ru
Stemborers cause 50% yield losses in cereal crops including maize, sorghum and sugarcane. In Kenya, stemborers include Busseola fusca, B. phaia, Sesamia calamistis, Eldana saccharina, Chilo orichalcociliellus and C. partellus. Control options for the various stemborers include use of pesticides, early planting, intercropping with noncereals and host plant resistance. In addition to being expensive, pesticides are environmentally unfriendly and are not fully effective due to the cryptic feeding behavior of the larvae. Thus the search for more efficient and convenient control methods for these pests is still ongoing. One of the other methods still being researched on is biological control where natural enemies, predators, parasitoids and pathogens, are used to lower the population of the pest to below economic injury level. Predators cannot keep the stemborers below economic injury levels, as pathogens and nematodes do not regulate the stemborer numbers. Parasitoids feed on immature stages of other insect host stages and kill them in the process. In Kenya C. sesamiae is one of the parasitoids that has been studied in regard to the control of stemborer pests. The relative importance of Cotesia sesamiae Cameron (Hymenoptera: Braconidae), a gregarious larval parasitoid of lepidopteran stemborers, varies significantly between regions. Two biotypes of the parasitoid have been described in Kenya: the coastal biotype, which is unable to develop in the noctuid B. fusca (Fuller) and the western biotype, which develops successfully in this host. Thus several strains of C. sesamiae from Kenya are envisaged for introduction into regions where B. fusca is the main pest icluding certain parts of Kenya such as Wundanyi (Taita-Taveta District,), and Central, and western Africa. In this study the reproductive compatibility of three populations of C. sesamiae was investigated using the noctuid S. calamistis and B. fusca as hosts. The effect of cross mating on the mating and oviposition behavior of C. sesamiae strains as well as the influence of parental strain of C. sesamiae on the fitness and sex ratio of their hybrid progeny was investigated. Further, the effect of Wolbachia treatment on the reproductive compatibility of the three strains was assessed. The three strains of C. sesamiae from coastal regions, central (Mt Kenya) and western (Kitale) were cross-mated among themselves giving rise to homogenic and heterogenic crosses. The mated females (whether cured or not) oviposited in fourth instar larvae of S. calamistis and B. fusca as hosts. Duration of searching, courting, foraging, mating and ovipositing was recorded. Data on searching, mating time and cross mating parameters were analyzed using analysis of variance (ANOVA). Means were separated by the Student-Newman-Keuls (SNK) test. The results showed that homogamic crosses of Mombasa uncured and Mt Kenya cured took a long time to mate (20.27±0.63a and 12.28±0.27) respectively. The number of Progeny produced varied among the crosses with cured Mombasa male mated with cured Kitale female having the highest with (33.0±0.la) and a sex ratio of 8% compared with uncured Mombasa male mated with uncured Kitale female having the lowest with (9.3±0.1 c) and a sex ratio of 0.6±0. I abcd, therefore curing affects mating behavior, progeny and sex ratio. The F1 individual were neither compatible among themselves nor with the parents. All parameters were highly significant apart from mean number of cocoons. The output of this work has helped to determine the effect of cross mating and oviposition behaviour of C. sesamia strains and the influence of crossing on sex ratio and progeny size and has helped to understand the possible consequences of the introduction and redistribution of C sesamiae for the sustainable control of stem borers in Africa.
Induction of malarial anaemia by haemozoin medicated suppression of erythropoiesis through dysregulation of IL-10 and IL-12 cytokines
(2011-08-10) Ouma, Emmanuel Yamo; Kongoro, Jedida A.; Perkins, D. J.
Severe malarial anaemia (SMA) is the leading cause of morbidity and mortality in young children less than five years residing in a Plasmodium falciparum holoendemic transmission area of western Kenya. Although the immunopathogenesis of SMA is largely uncharacterized, recent studies have shown that circulating interleukin-12 (IL12) production is suppressed during malarial anaemia. Since interleukin-10 (IL-10) and tumour necrosis factor alpha (TNF-a) suppress IL-12 production in a number of diseases, the profiles of these regulatory cytokines were investigated to determine the mechanism for IL-12 suppression in children with malarial anaemia. Moreover, monocytes and neutrophils acquire haemozoin (Hz) naturally during a malarial infection. In this study children aged three to thirty three months with Hz and healthy controls visiting the hospital were studied in a longitudinal prospective hospital-based design. Sample size was determined using sample size software. Malaria screening was performed using Giemsa-stained thick and thin blood films. Parasites were counted against 300 leucocytes and parasite density estimated using each individual's white blood cell (WBC) count. Hz was counted from 30 monocytes and 100 neutrophils and the level of haemozoination compared with haemoglobin levels, IL-10 and IL-12 production. Full haemogram was estimated using a Coulter counter. Multiplex assay was used to determine IL-10, IFN-y, TNF-a and IL-12p70 in plasma levels, which were then compared with Hz and haemoglobin (Hb) levels. Differences between median cytokine concentrations in various groups were tested using Kruskal Wallis test and pair wise comparisons using Mann-Whitney U test. The ratio of IL-l0:IL-12 was calculated for each individual and the difference among median ratio between various groups was compared using Mann-Whitney U test. Chi-square test was used to compare proportions. Results revealed that ingestion of naturally acquired malarial pigment (Hz) by monocytes increased the production of IL-10 and TNF-a, relative to IL-12, which correlated with increased severity of malarial anaemia. Further results revealed that elevated levels of Hz containing monocytes (HCM) (>10 %) was associated with significantly higher numbers of WBC (P < 0.0001), lymphocytes (P < 0.0001), and monocytes (P < 0.0001). In contrast, high HCM (> 10 %)'were inversely associated with red blood cells count (P < 0.0001), Hb (P < 0.0001), haematocrit (P < 0.0001), reticulocyte counts (P < 0.05), and platelet counts (P < 0.0001).It was concluded that elevated levels of Hz-deposition in monocytes are associated with increased severity of anaemia, leukocytic parameters and thrombocytopaenia.
Evaluation of polythylene based long lasting treated bed nets on the population density of indoor resting anopheles mosquitoes in Kanyaboli, Western-Kenya
(2011-08-10) Ojera, M.T. Odhiambo
Insecticide treated bednets have been shown to have a profound impact on malaria transmission in experimental trials in sub-saharan Africa. Their effectiveness requires frequent re-treatment, however re-treatment rates have rarely risen above 20%. The need for re-impregnation and the relatively short life span led to the development of long lasting insecticide bed nets (LLINs) for longer field use. Though these LLINs have shown good efficacy on malaria mosquitoes under control conditions, no fields study have been done of these LLIN for longer term field use. This study was therefore undertaken to evaluate the impact of deltamethrine treated bednets Netprotect, on density indoor resting of Anopheles mosquitoes in Western Kenya. In addition the study also investigated the impact of Netprotect on the feeding success of Anopheles mosquitoes' on human blood. These LLINs Netprotect bednets were randomly distributed in 150 matched houses. Another 150 houses were selected 2kms away as the control. These households recieved their bedntes six months later. Indoor resting mosquitoes from both areas were collected using Pyrethrum Spray Catch (PSC) and then sorted according to their psychological status namely, unfed, fed, and gravid. Blood meals were identified by a direct Enzyme linked immunosorbent assay (ELISA) using anti-host (IgG) conjugate. Malaria cases from both areas were followed passively in the nearby clinic by clinical diagnosis and rapid diagnosis test kit (Paracheque). Net efficacy was tested by exposing mosquitoes for 3 min using standard WHO test cones on selected net samples. Comparison of proportions between categorical variables was performed by chi-square test at 95% confidence level using SAS statistical software version 9. The findings revealed that the probability of finding An. funestus in control area was twice times more likely than in intervention area (OR=2.4,CI 1.7:3.5). There were decreased human feeding and increased cattle feeding by An. funestus in the intervention area. An arabiensis from this area was found to be highly zoophilic. Biossay on residual insecticidal activity indicated that Netprotect bed nets killed 80% of the exposed laboratory colony of susceptable An. gambiae s.s (Kisumu strain) after one year of use. The malaria cases followed for seven months at Ratuoro health center showed a reduced prevalence in the intervention area. These results indicated that Netprotect bednets were effective in controlling Anopheles mosquitoes during one year of use and this enhanced their ability to reduce malaria prevalence in the intervention area.
Effect of pineapple (Ananas comosus L. Merrill) and Papaya (Carica papaya L.) fruit extracts on sericin removal from silk moths cocoons in Kenya
(2011-08-10) Wainaina, Wairimu Pauline
Sericulture (Silk farming) is the rearing of silk moths for the production of raw silk. Silk farming originated from China where it was secretly practiced for many years before spreading to other parts of the world. Silk moths are grouped into mulberry silk moths (domesticated) and wild silk moths. Silk moth cocoon has a double filament made of insoluble protein known as fibroin which is embedded in a water soluble protein called sericin. Prior to processing cocoons, are boiled in strong alkali so as to dissolve the sericin a process called degumming. Proteinases enzymes such as papain from papaya (Carica papaya) and bromelain from pineapple (Ananas cosmosus) characterised by their proteolytic activity have the potential to hydrolyse sericin, thus increasing its solubility in water. This study sought to investigate the effect of extracts from pineapple and papaya on the solubility of sericin protein from cocoons of three species of silk moths: Gonometa postica, Argema mimosae and Bornbyx mori at different temperatures. Twenty cocoons of each species were cut open, cleaned to remove the pupae remains and weighed. The cleaned cocoons were immersed in the degumming agents at various temperatures and five cocoons were taken out at 30 minutes intervals for 120 minutes. These cocoons were dried for two hours and then re-weighed. The degumming agents used were crude extracts from papaya and pineapple, commercial papain, commercial bromelain and their effects were compared with that of the conventionally used sodium bicarbonate and distilled water. The efficiency of the degumming processes was assessed using mean weight loss at different temperatures and was subjected to analysis of variance (ANOVA). Where significant difference existed, mean separation was carried out using the StudentNewman-Keuls test. In G. postica cocoons, papain gave the highest mean weight loss at a temperature of 60°C for all time intervals. The highest mean weight loss from G.postica was 0.5 g at 60 °C, 120 minutes in G. postica cocoons this was significantly different from the mean weight loss with other treatments. The least mean weight loss in G. postica was recorded in water and ripe papaya treatment which was significantly lower than the other treatments extract. Amimosae cocoons showed highest weight loss with bromelain at 60°C, 90 minutes of but this was not significantly different with sodium bicarbonate. The least mean weight loss in A mimosae was recorded in papain and ripe papaya treatment 70°C, 120 minutes but this was not significantly lower than the other treatments extract. With B. mori cocoons, papain gave the highest mean weight loss of 0.12g at a temperature and time of 70° C, 60 minutes respectively, this was significantly different compared with the mean weight loss with all the other treatments. The results obtained from this study have shown that plant proteases can be utilised for effective degumming of cocoons. Commercial proteases were the best agent for degumming cocoons of G. postica and B. mori as it gave the highest mean sericin loss within the shortest duration. The results show that locally available fruit proteases can be used to remove sericin from silk moth cocoons. These offer farmers a cheaper local option while also shortening the time required for boiling hence saving fuel.

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