Sahiwal Breed in Pastoral Production Systems in Kenya: Future Roles and Existing Gaps in Knowledge and Supportive Technical Logistics; \u3ci\u3eA Review\u3c/i\u3e

Sahiwal genetic resources is an integral part of the ASALs economy of Kenya. Sahiwal is the largest single dual purpose cattle breed kept by the pastoral communities in the ASALs where livestock products are the main drivers of food and nutrition security, and a source of income to support other household obligations. It was introduced in Kenya to upgrade the low performing small east African Zebu because of its superior productive and reproductive performance. The promising results of this upgrading programme led to the breed gaining preference over the local Zebu among the Maasai pastoralists. Despite the impressive results from this breed and subsequent high demand for milk and beef due to increase in population, supply of superior bulls and cows from the nucleus herd to the commercial herds remain low. It is likely that the problem will continue and perhaps in future the numbers of Sahiwal population may reduce unless appropriate measures are put in place. Pastoralists and other stakeholders such as policy makers need technical guidance to identify the most seemly approaches to ensure long term breed multiplication and conservation as well as optimal utilisation in ASALs. This study looks at the underlying challenges and opportunities that are there to exploit advantages of the breed. Gaps in knowledge and supportive logistics for low input production system for the breed are also discussed as well as implications of Sahiwal cattle and practices and technologies for pastoral-based systems

Improved Livelihoods from Grasslands; the Case of Napier Grass in Smallholder Dairy Farms in Kenya

In Kenya, smallholder farmers produce about 80% of the marketed milk. The farming systems vary from mixed farms with up to 10 ha of land and \u3c 10 dairy cows (Gitau et al., 1994; Anon., 1985), to intensive smallholder dairy producers in the high human population central Kenya region with 0.9 to 2 ha of land and 3-4 dairy cows (Staal et al., 2001a). Milk production depends heavily on the cultivation of forages, with Pennisetum purpureum (Napier grass) by far the most important. An estimated 350,000 of the 600,000 smallholder farms in Kenya grow and utilize P. purpureum on their farms. There are various published data indicating the level of dependence on sown forages. In a survey of 21 smallholder dairy farmers in the highlands of Kenya, Romney et al. (2004) found that P. purpureum supplied approximately 40 and 60% of the feed offered to dairy cows in the dry and wet months respectively, with the remaining feed provided by concentrates, crop residues (mainly Zea mays (maize) stover) and other cut and carry fodder such as roadside grass. In the more intensive cut and carry systems of production practiced in central Kenya, McLeod et al. (2003) found that P. purpureum was grown by over 70% of the smallholder farmers in their study area. In farm level characterisation surveys of over 3300 households conducted between 1996 and 2000 in central Kenya, 62% kept livestock and more than 50% were growing P. purpureum. Farmers were also growing fodder legumes such as Sesbania grandiflora (Sesbania), Leucaena leucocephala (Leucaena), Calliandra calothyrsus (Callindra), Desmodium intortum/uncinatum, (Desmodium) and Medicago sativa (Lucerne), but the frequency did not exceed 7.5% (Staal et al., 2001b)

Differences In \u3ci\u3eUrochloa\u3c/i\u3e Hybrids and Cultivars Biomass Production in Several Sites in Western Kenya

Forage production is at the core of improved livestock productivity, especially in sub Saharan Africa. The genetic potential of existing animals remains underutilized due to limited forage quality and quantity. Albeit wide range of forage germplasm that exists, little data is available for identifying suitable genotypes, matched to specific environments and production systems. Due to the spatial and temporal diverse environments in which livestock production happens, multi-locational screening of forage production and characterizing genotype by environment interaction is key. We selected seven Urochloa (Syn. Brachiaria) genotypes comprising three hybrids and four cultivars and established them in on-farm trials in western Kenya for dry matter evaluation and nutritional quality. We selected eight sites covering four administrative counties (Siaya, Kakamega, Busia, Bungoma), and each county hosting two replicated trials, with each trial replicated 3 times. We observed dry matter yield differences across the counties in the order Bungoma \u3e Busia \u3e Kakamega \u3e Siaya. Similarly, the genotypes returned varied performance across the sites. Hybrids did well in one of the county, a mix of hybrids and cultivars in two counties and cultivars in the last county. Amongst sites, variation was least in Busia, and more pronounced in Bungoma. Continued assessments in subsequent cuts are underway. These will feed into context-specific recommendations about suitable forages for sustainable intensification in the face of global warming

Nutritional status of children admitted for diarrhoeal diseases in a referral hospital in western Kenya

Objectives: To determine the prevalence of malnutrition among children admitted with acute diarrhoea disease at Moi Teaching and Referral Hospital and to establish the effect of malnutrition on duration of hospital stay. Design: Prospective observational study. Setting: Paediatric wards of Moi Teaching and Referral Hospital, Eldoret, Kenya Subjects: A total of 191 children aged 6 and 59 months admitted with acute diarrhoea disease, without chronic co-morbidities or visible severe malnutrition, were systematically enrolled into the study between November 2011 and March 2012. Outcome Measures: Nutritional status based on WHO WHZ scores taken at admission and duration of hospital stay. Results:The mean age was 13.2 months with a male to female sex ratio of 1.16:1. Of all the children seen with acute diarrhoeal diseases, 43.9% had acute malnutrition ( Conclusion: Routine anthrometry including weight for height identifies more children with malnutrition in acute diarrhoeal diseases. Presence of malnutrition did not affect duration of hospital stay

The incidence and clinical burden of respiratory syncytial virus disease identified through hospital outpatient presentations in Kenyan children

There is little information that describe the burden of respiratory syncytial virus (RSV) associated disease in the tropical African outpatient setting. Methods We studied a systematic sample of children aged <5 years presenting to a rural district hospital in Kenya with acute respiratory infection (ARI) between May 2002 and April 2004. We collected clinical data and screened nasal wash samples for RSV antigen by immunofluorescence. We used a linked demographic surveillance system to estimate disease incidence. Results Among 2143 children tested, 166 (8%) were RSV positive (6% among children with upper respiratory tract infection and 12% among children with lower respiratory tract infection (LRTI). RSV was more likely in LRTI than URTI (p<0.001). 51% of RSV cases were aged 1 year or over. RSV cases represented 3.4% of hospital outpatient presentations. Relative to RSV negative cases, RSV positive cases were more likely to have crackles (RR = 1.63; 95% CI 1.34–1.97), nasal flaring (RR = 2.66; 95% CI 1.40–5.04), in-drawing (RR = 2.24; 95% CI 1.47–3.40), fast breathing for age (RR = 1.34; 95% CI 1.03–1.75) and fever (RR = 1.54; 95% CI 1.33–1.80). The estimated incidence of RSV-ARI and RSV-LRTI, per 100,000 child years, among those aged <5 years was 767 and 283, respectively. Conclusion The burden of childhood RSV-associated URTI and LRTI presenting to outpatients in this setting is considerable. The clinical features of cases associated with an RSV infection were more severe than cases without an RSV diagnosis

Allele Frequency–Based and Polymorphism-Versus-Divergence Indices of Balancing Selection in a New Filtered Set of Polymorphic Genes in Plasmodium falciparum

Signatures of balancing selection operating on specific gene loci in endemic pathogens can identify candidate targets of naturally acquired immunity. In malaria parasites, several leading vaccine candidates convincingly show such signatures when subjected to several tests of neutrality, but the discovery of new targets affected by selection to a similar extent has been slow. A small minority of all genes are under such selection, as indicated by a recent study of 26 Plasmodium falciparum merozoite-stage genes that were not previously prioritized as vaccine candidates, of which only one (locus PF10_0348) showed a strong signature. Therefore, to focus discovery efforts on genes that are polymorphic, we scanned all available shotgun genome sequence data from laboratory lines of P. falciparum and chose six loci with more than five single nucleotide polymorphisms per kilobase (including PF10_0348) for in-depth frequency–based analyses in a Kenyan population (allele sample sizes >50 for each locus) and comparison of Hudson–Kreitman–Aguade (HKA) ratios of population diversity (π) to interspecific divergence (K) from the chimpanzee parasite Plasmodium reichenowi. Three of these (the msp3/6-like genes PF10_0348 and PF10_0355 and the surf4.1 gene PFD1160w) showed exceptionally high positive values of Tajima's D and Fu and Li's F indices and have the highest HKA ratios, indicating that they are under balancing selection and should be prioritized for studies of their protein products as candidate targets of immunity. Combined with earlier results, there is now strong evidence that high HKA ratio (as well as the frequency-independent ratio of Watterson's θ/K) is predictive of high values of Tajima's D. Thus, the former offers value for use in genome-wide screening when numbers of genome sequences within a species are low or in combination with Tajima's D as a 2D test on large population genomic samples

Oral Administration of Electron-Beam Inactivated Rhodococcus equi Failed to Protect Foals against Intrabronchial Infection with Live, Virulent R. equi

There is currently no licensed vaccine that protects foals against Rhodococcus equi-induced pneumonia. Oral administration of live, virulent R. equi to neonatal foals has been demonstrated to protect against subsequent intrabronchial challenge with virulent R. equi. Electron beam (eBeam)-inactivated R. equi are structurally intact and have been demonstrated to be immunogenic when administered orally to neonatal foals. Thus, we investigated whether eBeam inactivated R. equi could protect foals against developing pneumonia after experimental infection with live, virulent R. equi. Foals (n = 8) were vaccinated by gavaging with eBeam-inactivated R. equi at ages 2, 7, and 14 days, or gavaged with equal volume of saline solution (n = 4), and subsequently infected intrabronchially with live, virulent R. equi at age 21 days. The proportion of vaccinated foals that developed pneumonia following challenge was similar among the vaccinated (7/8; 88%) and unvaccinated foals (3/4; 75%). This vaccination regimen did not appear to be strongly immunogenic in foals. Alternative dosing regimens or routes of administration need further investigation and may prove to be immunogenic and protective

How Much Does Malaria Vector Control Quality Matter: The Epidemiological Impact of Holed Nets and Inadequate Indoor Residual Spraying

BACKGROUND: Insecticide treated nets (ITN) and indoor residual spraying (IRS) are the two pillars of malaria vector control in Africa, but both interventions are beset by quality and coverage concerns. Data from three control programs were used to investigate the impact of: 1) the physical deterioration of ITNs, and 2) inadequate IRS spray coverage, on their respective protective effectiveness. METHODS: Malaria indicator surveys were carried out in 2009 and 2010 in Bioko Island, mainland Equatorial Guinea and Malawi to monitor infection with P. falciparum in children, mosquito net use, net condition and spray status of houses. Nets were classified by their condition. The association between infection and quality and coverage of interventions was investigated. RESULTS: There was reduced odds of infection with P. falciparum in children sleeping under ITNs that were intact (Odds ratio (OR): 0.65, 95% CI: 0.55-0.77 and OR: 0.81, 95% CI: 0.56-1.18 in Equatorial Guinea and in Malawi respectively), but the protective effect became less with increasingly worse condition of the net. There was evidence for a linear trend in infection per category increase in deterioration of nets. In Equatorial Guinea IRS offered protection to those in sprayed and unsprayed houses alike when neighbourhood spray coverage was high (≥80%) compared to those living in areas of low IRS coverage (<20%), regardless of whether the house they lived in was sprayed or not (adjusted OR = 0.54, 95% CI 0.33-0.89). ITNs provided only personal protection, offering no protection to non users. Although similar effects were seen in Malawi, the evidence was much weaker than in Equatorial Guinea. CONCLUSIONS: Universal coverage strategies should consider policies for repair and replacement of holed nets and promote the care of nets by their owners. IRS programs should ensure high spray coverage since inadequate coverage gives little or no protection at all

A versatile panel of reference gene assays for the measurement of chicken mRNA by quantitative PCR

Quantitative real-time PCR assays are widely used for the quantification of mRNA within avian experimental samples. Multiple stably-expressed reference genes, selected for the lowest variation in representative samples, can be used to control random technical variation. Reference gene assays must be reliable, have high amplification specificity and efficiency, and not produce signals from contaminating DNA. Whilst recent research papers identify specific genes that are stable in particular tissues and experimental treatments, here we describe a panel of ten avian gene primer and probe sets that can be used to identify suitable reference genes in many experimental contexts. The panel was tested with TaqMan and SYBR Green systems in two experimental scenarios: a tissue collection and virus infection of cultured fibroblasts. GeNorm and NormFinder algorithms were able to select appropriate reference gene sets in each case. We show the effects of using the selected genes on the detection of statistically significant differences in expression. The results are compared with those obtained using 28s ribosomal RNA, the present most widely accepted reference gene in chicken work, identifying circumstances where its use might provide misleading results. Methods for eliminating DNA contamination of RNA reduced, but did not completely remove, detectable DNA. We therefore attached special importance to testing each qPCR assay for absence of signal using DNA template. The assays and analyses developed here provide a useful resource for selecting reference genes for investigations of avian biology

Malaria misdiagnosis in Uganda – implications for policy change

BACKGROUND: In Uganda, like in many other countries traditionally viewed as harbouring very high malaria transmission, the norm has been to recommend that febrile episodes are diagnosed as malaria. In this study, the policy implications of such recommendations are revisited. METHODS: A cross-sectional survey was undertaken at outpatient departments of all health facilities in four Ugandan districts. The routine diagnostic practices were assessed for all patients during exit interviews and a research slide was obtained for later reading. Primary outcome measures were the accuracy of national recommendations and routine malaria diagnosis in comparison with the study definition of malaria (any parasitaemia on expert slide examination in patient with fever) stratified by age and intensity of malaria transmission. Secondary outcome measures were the use, interpretation and accuracy of routine malaria microscopy. RESULTS: 1,763 consultations undertaken by 233 health workers at 188 facilities were evaluated. The prevalence of malaria was 24.2% and ranged between 13.9% in patients >or=5 years in medium-to-high transmission areas to 50.5% for children <5 years in very high transmission areas. Overall, the sensitivity and negative predictive value (NPV) of routine malaria diagnosis were high (89.7% and 91.6% respectively) while the specificity and positive predictive value (PPV) were low (35.6% and 30.8% respectively). However, malaria was under-diagnosed in 39.9% of children less than five years of age in the very high transmission area. At 48 facilities with functional microscopy, the use of malaria slide examination was low (34.5%) without significant differences between age groups, or between patients for whom microscopy is recommended or not. 96.2% of patients with a routine positive slide result were treated for malaria but also 47.6% with a negative result. CONCLUSION: Current recommendations and associated clinical practices result in massive malaria over-diagnosis across all age groups and transmission areas in Uganda. Yet, under-diagnosis is also common in children <5 years. The potential benefits of malaria microscopy are not realized. To address malaria misdiagnosis, Uganda's policy shift from presumptive to parasitological diagnosis should encompass introduction of malaria rapid diagnostic tests and substantial strengthening of malaria microscopy