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Purpose: The objective of the study was to determine the effect of Strategic Human Resource Management Practices (SHRMPs) on performance of public universities. Methodology: This study was essentially guided by the Resource Based Theory, as exemplified by the philosophical inclination of the study was positivist ontology. The research used a descriptive research design, in a census approach. The target population of the study were all public universities in Kenya. Data was collected from 31 public universities in Kenya with the aid of a self-administered questionnaire. Out of the 117 questionnaires that were distributed, 110 were returned and were found to be usable providing a 71% response rate. Descriptive statistics and linear regression analyses were used to analyze the data. Findings: The main finding of the study indicated that there was a statistically significant relationship between the bundle of SHRMPs (rigorous recruitment, staff training, reward management and performance management), and performance of public universities in Kenya. The hypothesis of the study was that SHRMPs do not have an effect on the performance of public universities in Kenya. This finding was determined to be in tandem with the Resource Based Theory (Barney, 2001), which, among other points of emphasis, stresses the centrality of leveraging on people as key resources of an enterprise. The finding also resonated with empirical literature, including Al-Khaled & Chung (2020), who found that that entities which adopted strategic human resource management practices were able to sustainably improve their performance, and Mathushan & Kengatharan (2022), who found that the bundle of strategic human resource management practices, consisting of training, rewarding and performance management practices did positively impact on organizational performance. Unique Contribution to Theory, Practice and Policy: The finding of this study, that SHRM practices positively and significantly influence the performance of public universities, are arguably expansionary to the Resource Based Theory (RBT), as proponed by Barney (2001). Although the Resource Based Theory does not directly address strategic human resource management practices as elements of performance, it postulated that business entities needed to focus internally to activate resources, the most important one of which is the people resource. It is the people resource which enables such entities to achieve competitive advantage in their operations, given that it is the human resource which mobilizes, and creates value from the other resources within the enterprise. In this respect, therefore, it follows that every intervention made towards creating and enhancing the human resource capacity, including, as conceptualized in this study; rigorous recruitment, staff training, rewarding them and strategically managing their performance, does count, towards enhancing the contribution of the human resources, as exemplified by the Resource Based Theory, and consequently, activating the essential asset, towards competitive organizational performance. More directly, this empirical finding, regarding the positive influence of strategic human resource management practices on performance of public universities in Kenya has implications with respect to the public universities in Kenya. The main one is that, the public universities ought to take deliberate measures in determining and selecting appropriate SHRMPs. Such practices, according to the Resource Based Theory (Barney, 2001), are expected to be valuable, inimitable, and rare and may not be substitutable, in ensuring that public universities, like any other organizations, are able to sustainably achieve competitive advantage in their markets. This is further corroborated by the findings of Sagwa, K’Obonyo and Ogutu (2014), who averred that investing in human resources was crucial in promoting organizational performance. It is also the considered opinion of this study that, the finding that SHRMPs positively influenced the performance of public universities in Kenya, constituted new knowledge, at least, in extending the Resource Based Theory, as well as adding to the empirical literature with regard to strategic human resource management practices. Furthermore, the implications of the finding made, are more than likely to be relevant beyond the public universities sub-sector, and probably to include the entire public sector and, indeed, all organizations in general. To this end, therefore; human resource managers, HR departments, and units within public universities and other public and private entities, other human resource management practitioners, policy makers in HR-oriented public and private sector, as well as the community of researchers in human resource management and the related other disciplines, are likely to find the finding of this study useful. This is particularly considering the study’s recommendation that organizations have to identify and adopt appropriate bundles of SHRMPs that would reliably enable them to attain and sustain their competitive levels of performance.

East Coast fever, a tick-borne cattle disease caused by theTheileria parvaparasite, is among the biggest natural killers of cattle in East Africa, leading to over 1 million deaths annually. Here we report on the genetic analysis of a cohort of Boran cattle demonstrating heritable tolerance to infection byT. parva(h2= 0.65, s.e. 0.57). Through a linkage analysis we identify a 6 Mb genomic region onBos tauruschromosome 15 that is significantly associated with survival outcome followingT. parvaexposure. Testing this locus in an independent cohort of animals replicates this association with survival followingT. parvainfection. A stop gained polymorphism in this region was found to be highly associated with survival across both related and unrelated animals, with only one of the 20 homozygote carriers (T/T) of this change succumbing to the disease in contrast to 44 out of 97 animals homozygote for the reference allele (C/C). Consequently, we present a genetic locus linked to tolerance of one of Africa’s most important cattle diseases, raising the promise of marker-assisted selection for cattle that are less susceptible to infection byT. parva.Author SummaryMore than a million cattle die of East Coast fever in Africa each year, the impact of which disproportionately falls onto low-income, smallholder farmers. The lack of a widely accessible vaccine, heavy reliance on chemicals to control the tick vector and inadequate drug treatments means that new approaches for controlling the disease are urgently required. Through a genetic study of an extended pedigree of Boran cattle that are more than three times less likely to succumb to the disease than matched controls, we identify a region on chromosome 15 of the cattle genome associated with a high level of tolerance to the disease. We show that a variant in this region is also associated with survival in an independent cohort, and is linked to rates of cell expansion during infection. This genetic variant can therefore support marker-assisted selection, allowing farmers to breed tolerant cattle and offers a route to introduce this beneficial DNA to non-native breeds, enabling reduced disease incidence and increased productivity, which would be of benefit to millions of rural smallholder farmers across Africa.

Rhipicephalus appendiculatus is the major tick vector of Theileria parva, an apicomplexan protozoan parasite that causes the most economically important and lethal disease of cattle in East and central Africa. The African cape buffalo (Syncerus caffer) is the major wildlife host of T. parva from southern Uganda and Kenya to southern Africa. We show herein that R. appendiculatus appears to be absent from the two largest national parks in northern Uganda. Syncerus caffer is common in both of these national parks, specifically Murchison falls (MFNP) and Kidepo Valley (KVNP). We re-confirmed the previously reported absence of T. parva in buffalo sampled in the two northern parks based on RLB data using a nested PCR based on the T. parva p104 gene. By contrast, T. parva-infected R. appendiculatus ticks and parasite-infected buffalo were present in Lake Mburo (LMNP) in South central Uganda. This suggests that the distribution of R. appendiculatus, which is predicted to include the higher rainfall regions of northern Uganda, may be limited by additional, as yet unknown factors.

BackgroundTicks and tick-borne diseases are a major impediment to livestock production worldwide. Cattle trade and transnational transhumance create risks for the spread of ticks and tick-borne diseases and threaten cattle production in the absence of an effective tick control program. Few studies have been undertaken on cattle ticks in the Central African region; therefore, the need to assess the occurrence and the spatial distribution of tick vectors with the aim of establishing a baseline for monitoring future spread of tick borne-diseases in the region is urgent.ResultsA total of 7091 ixodid ticks were collected during a countrywide cross-sectional field survey and identified using morphological criteria. Of these, 4210 (59.4%) ticks wereAmblyomma variegatum, 1112 (15.6%)Rhipicephalus(Boophilus)microplus, 708 (10.0%)Rhipicephalus(Boophilus)decoloratus, 28 (0.4%)Rhipicephalus(Boophilus)annulatus, 210 (3.0%)Hyalomma rufipes, 768 (10.8%)Hyalomma truncatum, and 19 (0.3%)Rhipicephalus sanguineus.Three ticks of the genusHyalommaspp. and 33 of the genusRhipicephalusspp. were not identified to the species level. Cytochromecoxidase subunit 1 (cox1) gene sequencing supported the data from morphological examination and led to identification of three additional species, namelyHyalomma dromedarii,Rhipicephalus sulcatusandRhipicephalus pusillus. The finding of the invasive tick speciesR. microplusin such large numbers and the apparent displacement of the indigenousR. decoloratusis highly significant sinceR. microplusis a highly efficient vector ofBabesia bovis.ConclusionsThis study reports the occurrence and current geographical distribution of important tick vectors associated with cattle in Cameroon. It appears thatR. microplusis now well established and may be displacing nativeRhipicephalus(Boophilus) species, such asR. decoloratus. This calls for an urgent response to safeguard the livestock sector in western central Africa.

Background The Infection and Treatment Method (ITM) of vaccination is the only immunization procedure currently available to protect cattle against East Coast fever (ECF), a tick-transmitted disease responsible for losses of several hundreds of millions of dollars per year in sub-Saharan Africa. The vaccine comprises a homogenized preparation of infected ticks packaged in straws and stored in liquid nitrogen. The current manufacturing protocol results in straws containing 30–40 doses (ILRI 0804), which is impractical for immunizing small herds as found in dairy and smallholder farming systems. The ILRI 0804 SD stabilate was prepared as a 1:5 dilution of the parent stabilate, with the aim of producing vaccine stabilate straws containing between four to eight doses and thus suitable for smallholder farming systems. Infectivity of the diluted stabilate was assessed and the protective efficacy of the diluted stabilate was determined by performing experimental and field immunizations. Results Two groups of six cattle were inoculated with 1 ml of the diluted stabilate at 1:20 (equivalent to the recommended field dose for ILRI 0804, assuming no loss of sporozoite viability during thawing and refreezing) and 1:14 (assuming 30–35% loss of sporozoite viability). Schizonts were detected in all 12 animals, showing viability of sporozoites. Ten animals from the infectivity study and two control animals not previously exposed to T. parva were challenged with the parental ILRI 0804 stabilate. The results show that the two control animals displayed severe ECF reactions and were treated 14 days after challenge. Of the previously infected animals, only one underwent a severe reaction following challenge, a result in accord with the challenge experiments performed previously with the parent stabilate [Ticks Tick-Borne Dis 7:306-314, 2016]. The animal that displayed a severe reaction had no detectable schizonts and did not seroconvert following the initial inoculation with ILRI 0804 SD. In addition, 62 animals immunized under field conditions showed a mean seroconversion rate of 82%. Conclusion The results presented in this article demonstrate that it is possible to prepare straws suitable for use in smallholder herds by thawing, diluting and refreezing already packaged vaccine.

Rhipicephalus appendiculatus is an important tick vector of several pathogens and parasitizes domestic and wild animals across eastern and southern Africa. However, its inherent genetic variation and population structure is poorly understood. To investigate whether mammalian host species, geographic separation and resulting reproductive isolation, or a combination of these, define the genetic structure of R. appendiculatus, we analyzed multi-locus genotype data from 392 individuals from 10 geographic locations in Kenya generated in an earlier study. These ticks were associated with three types of mammalian host situations; (1) cattle grazing systems, (2) cattle and wildlife co-grazing systems (3) wildlife grazing systems without livestock. We also analyzed data from 460 individuals from 10 populations maintained as closed laboratory stocks and 117 individuals from five other species in the genus Rhipicephalus. The pattern of genotypes observed indicated low levels of genetic differentiation between the ten field populations (FST=0.014±0.002) and a lack of genetic divergence corresponding to the degree of separation of the geographic sampling locations. There was also no clear association of particular tick genotypes with specific host species. This is consistent with tick dispersal over large geographic ranges and lack of host specificity. In contrast, the 10 laboratory populations (FST=0.248±0.015) and the five other species of Rhipicephalus (FST=0.368±0.032) were strongly differentiated into distinct genetic groups. Some laboratory bred populations diverged markedly from their field counterparts in spite of originally being sampled from the same geographic locations. Our results demonstrate a lack of defined population genetic differentiation in field populations of the generalist R. appendiculatus in Kenya, which may be a result of the frequent anthropogenic movement of livestock and mobility of its several wildlife hosts between different locations.

Highlights • The Muguga cocktail was tested in cattle in a buffalo-only location. • Infection with buffalo-derived T. parva caused Corridor disease in cattle. • At the conservancy, the cocktail did not protect cattle against Corridor disease. • Efficacious vaccines can support integrative livestock/wildlife management., Graphical Abstract, Integrative management of wildlife and livestock requires a clear understanding of the diseases transmitted between the two populations. The tick-borne protozoan parasite Theileria parva causes two distinct diseases in cattle, East Coast fever and Corridor disease, following infection with parasites derived from cattle or buffalo, respectively. In this study, cattle were immunized with a live sporozoite vaccine containing three T. parva isolates (the Muguga cocktail), which has been used extensively and successfully in the field to protect against cattle-derived T. parva infection. The cattle were exposed in a natural field challenge site containing buffalo but no other cattle. The vaccine had no effect on the survival outcome in vaccinated animals compared to unvaccinated controls: nine out of the 12 cattle in each group succumbed to T. parva infection. The vaccine also had no effect on the clinical course of the disease. A combination of clinical and post mortem observations and laboratory analyses confirmed that the animals died of Corridor disease. The results clearly indicate that the Muguga cocktail vaccine does not provide protection against buffalo-derived T. parva at this site and highlight the need to evaluate the impact of the composition of challenge T. parva populations on vaccine success in areas where buffalo and cattle are present.

Background The ixodid tick Rhipicephalus appendiculatus transmits the apicomplexan protozoan parasite Theileria parva, which causes East coast fever (ECF), the most economically important cattle disease in eastern and southern Africa. Recent analysis of micro- and minisatellite markers showed an absence of geographical and host-associated genetic sub-structuring amongst field populations of R. appendiculatus in Kenya. To assess further the phylogenetic relationships between field and laboratory R. appendiculatus tick isolates, this study examined sequence variations at two mitochondrial genes, cytochrome c oxidase subunit I (COI) and 12S ribosomal RNA (rRNA), and the nuclear encoded ribosomal internal transcribed spacer 2 (ITS2) of the rRNA gene, respectively. Results The analysis of 332 COI sequences revealed 30 polymorphic sites, which defined 28 haplotypes that were separated into two distinct haplogroups (A and B). Inclusion of previously published haplotypes in our analysis revealed a high degree of phylogenetic complexity never reported before in haplogroup A. Neither haplogroup however, showed any clustering pattern related to either the geographical sampling location, the type of tick sampled (laboratory stocks vs field populations) or the mammalian host species. This finding was supported by the results obtained from the analysis of 12S rDNA sequences. Analysis of molecular variance (AMOVA) indicated that 90.8 % of the total genetic variation was explained by the two haplogroups, providing further support for their genetic divergence. These results were, however, not replicated by the nuclear transcribed ITS2 sequences likely because of recombination between the nuclear genomes maintaining a high level of genetic sequence conservation. Conclusions COI and 12S rDNA are better markers than ITS2 for studying intraspecific diversity. Based on these genes, two major genetic groups of R. appendiculatus that have gone through a demographic expansion exist in Kenya. The two groups show no phylogeographic structure or correlation with the type of host species from which the ticks were collected, nor to the evolutionary and breeding history of the species. The two lineages may have a wide geographic distribution range in eastern and southern Africa. The findings of this study may have implications for the spread and control of R. appendiculatus, and indirectly, on the transmission dynamics of ECF. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1631-1) contains supplementary material, which is available to authorized users.

Background The tick population of Africa includes several important genera belonging to the family Ixodidae. Many of these ticks are vectors of protozoan and rickettsial pathogens including Theileria parva that causes East Coast fever, a debilitating cattle disease endemic to eastern, central and southern Africa. Effective surveillance of tick-borne pathogens depends on accurate identification and mapping of their tick vectors. A simple and reproducible technique for rapid and reliable differentiation of large numbers of closely related field-collected ticks, which are often difficult and tedious to discriminate purely by morphology, will be an essential component of this strategy. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) is increasingly becoming a useful tool in arthropod identification and has the potential to overcome the limitations of classical morphology-based species identification. In this study, we applied MALDI-TOF MS to a collection of laboratory and field ticks found in Eastern Africa. The objective was to determine the utility of this proteomic tool for reliable species identification of closely related afrotropical ticks. Methods A total of 398 ixodid ticks from laboratory maintained colonies, extracted from the hides of animals or systematically collected from vegetation in Kenya, Sudan and Zimbabwe were analyzed in the present investigation. The cytochrome c oxidase I (COI) genes from 33 specimens were sequenced to confirm the tentatively assigned specimen taxa identity on the basis of morphological analyses. Subsequently, the legs of ticks were homogenized and analyzed by MALDI-TOF MS. A collection of reference mass spectra, based on the mass profiles of four individual ticks per species, was developed and deposited in the spectral database SARAMIS™. The ability of these superspectra (SSp.) to identify and reliably validate a set of ticks was demonstrated using the remaining individual 333 ticks. Results Ultimately, ten different tick species within the genera Amblyomma, Hyalomma, Rhipicephalus and Rhipicephalus (Boophilus) based on molecular COI typing and morphology were included into the study analysis. The robustness of the 12 distinct SSp. developed here proved to be very high, with 319 out of 333 ticks used for validation identified correctly at species level. Moreover, these novel SSp. allowed for diagnostic specificity of 99.7 %. The failure of species identification for 14 ticks was directly linked to low quality mass spectra, most likely due to poor specimen quality that was received in the laboratory before sample preparation. Conclusions Our results are consistent with earlier studies demonstrating the potential of MALDI-TOF MS as a reliable tool for differentiating ticks originating from the field, especially females that are difficult to identify after blood feeding. This work provides further evidence of the utility of MALDI-TOF MS to identify morphologically and genetically highly similar tick species and indicates the potential of this tool for large-scale monitoring of tick populations, species distributions and host preferences. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1424-6) contains supplementary material, which is available to authorized users.

Background Rhipicephalus appendiculatus is the primary vector of Theileria parva, the etiological agent of East Coast fever (ECF), a devastating disease of cattle in sub-Saharan Africa. We hypothesized that a vaccine targeting tick proteins that are involved in attachment and feeding might affect feeding success and possibly reduce tick-borne transmission of T. parva. Here we report the evaluation of a multivalent vaccine cocktail of tick antigens for their ability to reduce R. appendiculatus feeding success and possibly reduce tick-transmission of T. parva in a natural host-tick-parasite challenge model. Methods Cattle were inoculated with a multivalent antigen cocktail containing recombinant tick protective antigen subolesin as well as two additional R. appendiculatus saliva antigens: the cement protein TRP64, and three different histamine binding proteins. The cocktail also contained the T. parva sporozoite antigen p67C. The effect of vaccination on the feeding success of nymphal and adult R. appendiculatus ticks was evaluated together with the effect on transmission of T. parva using a tick challenge model. Results To our knowledge, this is the first evaluation of the anti-tick effects of these antigens in the natural host-tick-parasite combination. In spite of evidence of strong immune responses to all of the antigens in the cocktail, vaccination with this combination of tick and parasite antigens did not appear to effect tick feeding success or reduce transmission of T. parva. Conclusion The results of this study highlight the importance of early evaluation of anti-tick vaccine candidates in biologically relevant challenge systems using the natural tick-host-parasite combination. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1774-0) contains supplementary material, which is available to authorized users.

The current Infection and Treatment Method of vaccination against East Coast fever comprises an inoculation of live Theileria parva sporozoites and simultaneous administration of oxytetracycline. Immunization with a combination of parasite types has been shown to provide broader protection than inoculation of individual strains. In this study, we used a high-throughput capillary electrophoresis system to determine the genotypic composition of the Muguga Cocktail, a widely used vaccine stabilate derived from three seed stabilates-Muguga, Serengeti-transformed and Kiambu 5. Five satellite markers were used to genotype the vaccine and reference stabilates from two commercial-scale preparations of the vaccine. In addition, 224 cloned cell lines established by infection of bovine lymphocytes with T. parva parasites from the component stabilates were genotyped. The results indicate that, for the recently prepared batch, there are at least eight genotypes in each of the Muguga and the Serengeti-transformed stabilates, while parasites from the Kiambu 5 stabilate showed no diversity at the five loci. The Serengeti-transformed stabilate contained parasites of the Kiambu 5 genotype and of two genotypes present in the Muguga stabilate, whereas there were no genotypes common to the Muguga and Kiambu 5 stabilates. When stabilates from the two vaccine batches were compared, no allelic variations were identified between the Muguga and Kiambu 5 parasites, while lack of sufficient clones prevented a full comparison of the Serengeti-transformed stabilates. The findings will facilitate examination of the extent to which the vaccine strains become resident in areas under vaccination, the identification of 'breakthrough' strains and the establishment of the quality assurance protocols to detect variations in the production of the vaccine. The cloned cell lines will be useful for further understanding the antigenic diversity of parasites in the vaccine.

Wide interest margins as witnessed in Kenya are a sign of a repressed and inefficient financial sector. This paper carries out a cross-country analysis of the determinants of financial market efficiency using panel cointegration with a view to recommending policy options for improving the efficiency of the financial sector intermediation process in Kenya. The study finds that the major contributors to the differences in financial sector inefficiency in Kenya compared to the other countries in the study are high bank operating costs, default risk and financial market structure. The study recommends, among other measures, that the government through the Central Bank need to collaborate with the commercial banks and establish a working credit reference bureau to enable easy identification of credit worthy customers in order to reduce default risk; there is also need by the central bank to license more new banks to increase competition and reduce bank concentration. The study also recommends increased use of technology including phone-banking and e-banking to reduce operation costs of the banks. The paper concludes that contrary to the findings from other cross-country analysis, the factors that lead to financial market in/efficiency varies from one country to the other.

The transcriptional control of gene expression is not well documented in the Arthropoda. We describe transcriptional analysis of two exceptionally divergent homologues (Ra86) of the Bm86 gut antigen from Rhipicephalus appendiculatus. Bm86 forms the basis of a commercial vaccine for the control of Rhipicephalus (Boophilus) microplus. The R. appendiculatus Ra86 proteins contain 654 and 693 amino acids, with only 80% amino acid sequence identity. Reverse-transcription PCR of gut cDNA showed transcription of only one genotype in individual female ticks. PCR amplification of 3' untranslated sequences from genomic DNA indicated that both variants could be encoded within a single genome. When both variants were present, one of the two Ra86 genotypes was transcriptionally dominant.

Background: Thymic differentiation is important and determines the strength of adaptive immunity in mammals in their later days in life. There are many factors that have been found to influence the development of T lymphocytes in the thymus and these include the effect of hedgehog signalling family of proteins. Immunologists and other basic science researchers have established the role of Indian hedgehog and sonic hedgehog in thymocytes development in the recent past, but the role of hedgehog is not well known. The aim of this study was to determine the influence of Desert hedgehog in CD4:CD8 ratio in developing thymocytes of mice.Methods: Smashed thymocytes from mice deficient of Desert hedgehog and those with an intact gene coding for this protein were prepared in a cell suspension using standard procedurs. The cell suspensions were stained using fluorochrome-labelled monoclonal anti: CD4-PE, CD8-TRI, CD3-FITC, CD5-FITC, CD44-PE and CD25-FITC (e-Bioscience). Samples were analyzed using a three-color flow cytometry. The flow cytometry-generated data was analyzed using flowjo (Treestar, USA). Statistical significance of the findings was determined using paired t-test and reported at pResults: There was a general upward trend on CD4+CD8+ double positive thymocytes in Desert hedgehog mice relative to WT controls. An analysis of CD4:8 ratio revealed a reduced ratio in Dhh KO mice compared to that of WT controls attributable to the finding that there might have been a preferential differentiation of DP CD4+CD8+ to SP CD4+ in Dhh knockout mice as demonstrated by percentage of thymic subsets. The results of this study were not statistically significant and this was blamed on the fewer number of animals used in the study.Conclusions: Dhh might have a role arresting the DP cell subjects from differentiating preferentially to CD4+ T cells. To get statistically significant findings, these experiments could be repeated with a larger animal sample.

Background: The process of thymic proliferation and differentiation in mammals is indispensable. The role of hedgehog family of proteins has been extensively studied in the recent past years. Specifically, scientists have carried out substantial amount of work on Sonic hedgehog (Shh) and Indian hedgehog (Ihh) and published on their roles on either T-cell development or peripheral T-cell activation. However, the role of Desert hedgehog (Dhh) the third member of the hedgehog family of proteins, in T-cell development has not been clearly understood. In this work, we aimed to investigate the role of Desert hedgehog in thymic differentiation, particularly in the double negative T cell developmental stages.Methods: Thymuses of three Dhh-/- mice, three Dhh+/- and three Dhh+/+ were obtained by killing the mice using A prepared suspension of cells was analyzed by a three-color flow Cytometry and the acquired data analyzed using flow jo, a tree star software for flow cytometry data analysis. To establish the statistical significance of the findings, data was subjected to student t-test and significance reported at critical p-value of 0.05.Results: The total number of thymic cells was found to be higher in Dhh KO mice relative to the WT control. Analysis of thymic subsets using flow cytometry showed that double negative CD4-CD8- thymocytes were found to be relatively higher in Dhh-/- mice compared to Dhh+/+ control. In particular the percentage representation of CD44-CD25+ DN3 thymocytes were significantly higher (p=0.03) in Dhh KO mice relative to the WT controls.Conclusions: The findings of this study suggest that Dhh signal could be a negative regulator during early thymic differentiation. The data shown here is representative of three separate experiments. To get much clearer and replicative findings, these experiments can be repeated with a much larger sample size.

Background: Dog bites and subsequent transmission of rabies virus continue to be a public health threat in some parts of the world. While prophylaxis has proven successful in limiting transmission of rabies virus, dog vaccination coverage has been far below the WHO-recommended level of 75% in many parts, particularly in Africa and Asia. Aim: The aim of this study was to determine the level of dog vaccination coverage in Moiben Subcounty of Uasin Gishu County, Kenya. The study also sought to investigate the reasons for possible low dog vaccination coverage. Methodology: The dog owners were interviewed using structured questionnaires on whether they had their dogs vaccinated, the frequency of vaccination and the number of dogs maintained per household. The respondents were also interviewed on whether their dogs were confined or not and whether they had bitten residents or not. Data was entered into SPSS version 22 of 2013 for analysis. The data was analyzed using chi square and the statistical significance determined at critical p-value of 0.05 and 0.01 in some cases. Results: The coverage of dog vaccination against rabies virus in Moiben Sub-county, Uasin Gishu County was found to be 19.5% (130/666). The number of dogs that had not been vaccinated were 536 out of 666 accounting for 80.5% of the sample in this study. It was established that 32.7% of dogs kept in singles per household and 5.9% of dogs kept in more than 4 dogs per household were vaccinated. The findings show that number of dogs kept by each household is significantly associated (X²=32.2) with the level of vaccination coverage. We also found that a total of 351 (54.6) children below 15 years were the majority who had been bitten by dogs (X² =26.3, p= 0.01) while the least bitten were those above 46 years of age. It was also established that the unconfined dogs (487/75.7%) significantly bit more people than those that were partially confined (X² =12.9, p= 0.01) Conclusion and Recommendation: The dog vaccination coverage at 19.5% in Moiben Subcounty is far below the 75% level recommended by the WHO. The frequency of dog vaccination was found to be once a year among some dog owners, twice among a few others, and once in the life-time of the dog among some dog owners. There was an inverse proportionality between vaccination frequency and the number of dogs owned per household. Dog confinement limits dog bites and hence should be enforced among dog owners. This study recommends that households in Moiben Sub-county keep the number of dogs that they can manage with regards to vaccination to be able to control rabies virus transmission. The county government of Uasin Gishu should move with speed to make and implement a policy on dog ownership to regulate the number of dogs owned per household.

Integrative management of wildlife and livestock requires a clear understanding of the diseases transmitted between the two populations. The tick-borne protozoan parasite Theileria parva causes two distinct diseases in cattle, East Coast fever and Corridor disease, following infection with parasites derived from cattle or buffalo, respectively. In this study, cattle were immunized with a live sporozoite vaccine containing three T. parva isolates (the Muguga cocktail), which has been used extensively and successfully in the field to protect against cattle-derived T. parva infection. The cattle were exposed in a natural field challenge site containing buffalo but no other cattle. The vaccine had no effect on the survival outcome in vaccinated animals compared to unvaccinated controls: nine out of the 12 cattle in each group succumbed to T. parva infection. The vaccine also had no effect on the clinical course of the disease. A combination of clinical and post mortem observations and laboratory analyses confirmed that the animals died of Corridor disease. The results clearly indicate that the Muguga cocktail vaccine does not provide protection against buffalo-derived T. parva at this site and highlight the need to evaluate the impact of the composition of challenge T. parva populations on vaccine success in areas where buffalo and cattle are present.

Theileria parva is the etiologic agent of East Coast fever, an economically important disease of cattle in sub-Saharan Africa. This protozoan parasite is biologically transmitted by Rhipi- cephalus appendiculatus (Neumann) (Acari: Ixodidae). An understanding of the vectorÐparasite interaction may aid the development of improved methods for controlling transmission. We developed quantitative polymerase chain reaction (qPCR) and nested PCR (nPCR) assays targeting the T. parva-speciÞc p104 gene to study T. parva pathogenesis in two strains of R. appendiculatus that had previously been selected to be relatively more (Kiambu) or less (Muguga) susceptible to infection. Nymphs from both strains were fed simultaneously to repletion on acutely infected calves. Nymphs from the Kiambu strain showed signiÞcantly higher engorgement weights compared with Muguga strain nymphs. Immediately after engorgement qPCR conÞrmed that nymphal Kiambu ticks had signiÞcantly higher parasite loads at repletion than Muguga nymphs. By 12 d postengorgement, parasites were below quantiÞable levels but could be detected by nPCR in 83Ð 87% (Muguga and Kiambu, respectively) of nymphs. After the molt, adult feeding on nao¨ve cattle stimulated parasite replication in the salivary glands. PCR detected signiÞcantly more infected ticks than microscopy, and there was a signiÞcant difference between the two tick strains both in the proportion of ticks that develop salivary gland infections, and in the number of parasites within infected salivary glands. These data conÞrm that although both tick strains were competent vectors, Kiambu is both a signiÞcantly more susceptible and a more efÞcient host for T. parva than Muguga. The mechanisms that contribute to the levels of susceptibility and efÞciency are unknown; however, this study lays the groundwork for a comparison of the transcriptome of these tick strains, the next step toward discovering the genes involved in the tickÐparasite interaction.

Vaccines based on recombinant Bm86 gut antigen from Boophilus microplus are a useful component of integrated control strategies against B. microplus infestations of cattle. The capacity of such vaccines to control heterologous infestations by two African tick species was investigated. The mean weight of engorged female ticks and mean egg mass per tick were significantly reduced in B. decoloratus infestations, but there was no effect of the vaccine against adult Rhipicephalus appendiculatus. We cloned, sequenced and expressed two Bm86 homologues (Bd86) from B. decoloratus. Amino acid sequence identity between Bd86 homologues (Bd86-1 and Bd86-2) and Bm86 was 86% and 85%, respectively, compared to 93% identity between the variants. Native Bd86 protein in B. decoloratus tick mid-gut sections and recombinant Bd86-1 reacted strongly with sera from TickGARD vaccinated cattle. TickGARD can therefore protect against a heterologous tick species with multiple antigen sequences. Epitope mapping using sera from TickGARD-vaccinated cattle identified two linear peptides conserved between the Bd86 homologues and Bm86. These epitopes represent candidate synthetic peptide vaccines for control of Boophilus spp. and the pathogens transmitted by these tick vectors.

The Infection and Treatment Method (ITM) of vaccination against the apicomplexan parasite Theileria parva has been used since the early 1970s and is still the only commercially available vaccine to combat the fatal bovine disease, East Coast fever (ECF). The disease is tick-transmitted and results in annual economic losses of at least $300 million per year. While this vaccine technology has been available for over 40 years, few attempts have been made to standardize the production process and characterize the vaccine. The latest batch was produced in early 2008 at the International Livestock Research Institute (ILRI). The vaccine production involves the use of cattle free from parasites routinely monitored throughout the production process, and a pathogen-free tick colony. This paper describes the protocol used in the recent production, and the process improvements, including improved quality control tools, that had not been employed in previous ITM productions. The paper also describes the processes involved in determining the appropriate field dose, which involved a three-step in vivo study with various dilutions of the vaccine stabilate. The vaccine was shown to be safe and viable after production, and a suitable field dose was identified as 1 ml of a 1:100 dilution.

Background There are no commercially available vaccines against human protozoan parasitic diseases, despite the success of vaccination-induced long-term protection against infectious diseases. East Coast fever, caused by the protist Theileria parva, kills one million cattle each year in sub-Saharan Africa, and contributes significantly to hunger and poverty in the region. A highly effective, live, multi-isolate vaccine against T. parva exists, but its component isolates have not been characterized. Here we sequence and compare the three component T. parva stocks within this vaccine, the Muguga Cocktail, namely Muguga, Kiambu5 and Serengeti-transformed, aiming to identify genomic features that contribute to vaccine efficacy. Results We find that Serengeti-transformed, originally isolated from the wildlife carrier, the African Cape buffalo, is remarkably and unexpectedly similar to the Muguga isolate. The 420 detectable non-synonymous SNPs were distributed among only 53 genes, primarily subtelomeric antigens and antigenic families. The Kiambu5 isolate is considerably more divergent, with close to 40,000 SNPs relative to Muguga, including >8,500 non-synonymous mutations distributed among >1,700 (42.5 %) of the predicted genes. These genetic markers of the component stocks can be used to characterize the composition of new batches of the Muguga Cocktail. Conclusions Differences among these three isolates, while extensive, represent only a small proportion of the genetic variation in the entire species. Given the efficacy of the Muguga Cocktail in inducing long-lasting protection against infections in the field, our results suggest that whole-organism vaccines against parasitic diseases can be highly efficacious despite considerable genome-wide differences relative to the isolates against which they protect., BMC Genomics, 16, ISSN:1471-2164

Two recombinant vaccines against Theileria parva, based on a near full-length version of the sporozoite surface antigen p67 (p67 635 ), or an 80 amino acid C-terminal section (p67C), were evaluated by exposure of immunized cattle to natural tick challenge in two sites at the Kenya Coast and one in Central Kenya. Vaccination reduced severe ECF by 47% at the coast and by 52% in central Kenya from an average incidence of 0.53 ± 0.07 (S.E.) in 50 non-immunised controls to an average of 0.27 ± 0.05 in 83 immunised animals. The reduction in severe East Coast fever was similar to that observed in laboratory experiments with p67 635 and p67C. The p67 coding sequence from thirteen T . parva field isolates including seven from vaccinated cattle that were not protected, was 100% identical to the gene on which the recombinant vaccine is based, suggesting a predominantly homologous p67 antigenic challenge. The same parasite isolates were however genetically heterogeneous at several loci other than p67.

We describe the generation of an auto-annotated index of genes that are expressed in the salivary glands of four-day fed female adult Rhipicephalus appendiculatus ticks. A total of 9162 EST sequences were derived from an uninfected tick cDNA library and 9844 ESTs were from a cDNA library from ticks infected with Theileria parva, which develop in type III salivary gland acini. There were no major differences between abundantly expressed ESTs from the two cDNA libraries, although there was evidence for an up-regulation in the expression of some glycine-rich proteins in infected salivary glands. Gene ontology terms were also assigned to sequences in the index and those with potential enzyme function were linked to the Kyoto encyclopedia of genes and genomes database, allowing reconstruction of metabolic pathways. Several genes code for previously characterized tick proteins such as receptors for myokinin or ecdysteroid and an immunosuppressive protein. cDNAs coding for homologs of heme-lipoproteins which are major components of tick hemolymph were identified by searching the database with published N-terminal peptide sequence data derived from biochemically purified Boophilus microplus proteins. The EST data will be a useful resource for construction of microarrays to probe vector biology, vector-host and vector-pathogen interactions and to underpin gene identification via proteomics approaches.

Random clones from a cDNA library made from mRNA purified from dissected salivary glands of feeding female Amblyomma variegatum ticks were subjected to single pass sequence analysis. A total of 3,992 sequences with an average read length of 580 nucleotides have been used to construct a gene index called AvGI that consists of 2,109 non-redundant sequences. A provisional gene identity has been assigned to 39% of the database entries by sequence similarity searches against a non-redundant amino acid database and a protein database that has been assigned gene ontology terms. Homologs of genes encoding basic cellular functions including previously characterised enzyme activities, such as stearoyl CoA saturase and protein phosphatase, of ixodid tick salivary glands were found. Several families of abundant cDNA sequences that may code for protein components of tick cement and A. variegatum proteins which may contribute to anti-haemostatic and anti-inflammatory responses, and, one with potential immunosuppressive activity, were also identified. Interference with the function of such proteins might disrupt the life cycle of A. variegatum and help to control this ectoparasite or to reduce its ability to transmit disease causing organisms. AvGI represents an electronic knowledge base, which can be used to launch investigations of the biology of the salivary glands of this tick species. The database may be accessed via the World Wide Web at http://www.tigr.org/tdb/tgi.shtml.

Background: Rabies virus still causes human and animal deaths around the world. Human rabies is transmitted by an infected canine. If rabies-infected person is not treated within 48 hours, the virus could move to the central nervous system and cause irreversible cell damage that could be fatal. The aim of this study was to establish risk factors for dog bites in Moiben Sub-county, and whether there is a significant association between dog bite frequency and those risk factors.Methods: A total of 339 respondents were selected from a total of 1152 households using multistage sampling, simple random sampling and systematic sampling methods. The head of the household responded to interviewer-administered questionnaires. Data was analyzed using SPSS version 22 of 2013. Associations were tested using chi square test and any associations reported at critical p-value of 0.05 and 95% confidence interval. Results: This Study found more children

Histoplasmosis is a serious community acquired fungal infection among immunocompetent and immunocompromised individuals. Chicken droppings were evaluated for the presence of Histoplasma capsulatum, by culturing in Blood agar, SABHI and SDA agar at 25°C and 37°C. Exoantigen were used for confirmation. Two Histoplasma capsulatum were isolated in this study. The study found that Chicken droppings harbor Histoplasma species.

Commercial vaccines based on the tick gut protein Bm86 have been successful in controlling the one-host tick Rhipicephalus (Boophilus) microplus and provide heterologous protection against certain other non-target ixodid tick species. This cross protection, however, does not extend to the three-host tick R. appendiculatus, the vector of the protozoan parasite Theileria parva. When transmitted to cattle, T. parva causes the often fatal disease East Coast fever. Here, we used insect cell-expressed recombinant versions of the R. appendiculatus homologs of Bm86, named Ra86, to vaccinate cattle. We measured multiple fitness characteristics for ticks that were fed on cattle Ra86-vaccinated or unvaccinated. The Ra86 vaccination of cattle significantly decreased the molting success of nymphal ticks to the adult stage. Modeling simulations based on our empirical data suggest that repeated vaccinations using Ra86 could reduce tick populations over successive generations. Vaccination with Ra86 could thus form a component of integrated control strategies for R. appendiculatus leading to a reduction in use of environmentally damaging acaricides.

Biological differences, including vector competence for the protozoan parasite Theileria parva have been reported among populations of Rhipicephalus appendiculatus (Acari: Ixodidae) from different geographic regions. However, the genetic diversity and population structure of this important tick vector remain unknown due to the absence of appropriate genetic markers. Here, we describe the development and evaluation of a panel of EST micro- and minisatellite markers to characterize the genetic diversity within and between populations of R. appendiculatus and other rhipicephaline species. Sixty-six micro- and minisatellite markers were identified through analysis of the R. appendiculatus Gene Index (RaGI) EST database and selected bacterial artificial chromosome (BAC) sequences. These were used to genotype 979 individual ticks from 10 field populations, 10 laboratory-bred stocks, and 5 additional Rhipicephalus species. Twenty-nine markers were polymorphic and therefore informative for genetic studies while 6 were monomorphic. Primers designed from the remaining 31 loci did not reliably generate amplicons. The 29 polymorphic markers discriminated populations of R. appendiculatus and also 4 other Rhipicephalus species, but not R. zambeziensis. The percentage Principal Component Analysis (PCA) implemented using Multiple Co-inertia Analysis (MCoA) clustered populations of R. appendiculatus into 2 groups. Individual markers however differed in their ability to generate the reference typology using the MCoA approach. This indicates that different panels of markers may be required for different applications. The 29 informative polymorphic micro- and minisatellite markers are the first available tools for the analysis of the phylogeography and population genetics of R. appendiculatus.

An improved Theileria parva DNA detection assay based on the polymerase chain reaction (PCR) using primers derived from the 104 kDa antigen (p104) gene was developed to detect parasite DNA in blood spots on filter paper. The specificity of the assay was validated using DNA from a wide range of cattle-derived and buffalo-derived stocks of T. parva. DNA of T. annulata, T. buffeli, T. lestoquardi, T. mutans and T. taurotragi was not amplified using the p104 primers. The detection threshold of the assay was ∼1–2 parasites/μl of infected blood. PCR amplification using the p104 primers was applied to sequential samples from groups of cattle experimentally infected with either the T. parva Marikebuni stock that induces a long-term carrier state or the Muguga stock, which does not induce a carrier state. The study extended for up to 487 days post-infection and PCR data from defined time points were compared with parasitological microscopy and serological data, together with xenodiagnosis by experimental application of ticks. Microscopy first detected piroplasms between days 13 and 16 after infection whereas all cattle became PCR +ve between days 9 and 13. Animals infected with the Muguga stock of T. parva had parasite DNA in the peripheral blood, which could be detected by PCR, for between 33 and 129 days post-infection in different animals. By contrast parasite DNA in the blood of cattle infected with the Marikebuni stock could be detected consistently from day 9 up to 487 days, when the study terminated. The data suggest that the nature and persistence of the carrier state may differ markedly between different T. parva parasite stocks.