Bivariate Based Susceptibility Mapping for Gully Erosion in Wanjoga River Catchment Upper Tana Basin, Kenya

Gullies occur in semi-arid regions characterized by rainfall variability and seasonality, increased overland flow, affecting ecological fragility of an area. In most gully prone areas, extent of land affected by gullies is increasing. Thus, predicting susceptibility to gully erosion in semi-arid environment is an important step towards effectively rehabilitating and prevention against gully erosion. Proneness to gully occurrence was assessed against; Land cover/land use, slope, soil characteristics, rainfall variability and elevation, and modelled using geographical information system (GIS)-based bivariate statistical approach. Objectives of the study were; a) to assess influence of geomorphological factors on gully erosion, b) analyze and develop gully erosion susceptibility map, c) verify gully susceptibility images using error matrix of class labels in classified map against ground truth reference data. Total of 66 gullied areas (width and depth ≥ ranging 0.5), were mapped using 15m resolution Landsat images for 2018 and field surveys to estimate susceptibility to gully erosion by Global Mapper software in GIS. The images were verified using 120 pixels of known 15 gully presence or absence to produce an error matrix based on comparison of actual outcomes to predicted outcomes. Influence of conditioning factors to gully erosion showed a significant positive relationship between gully susceptibility and gully conditioning factors with consistency value; CR =0.097; value< 0.1, indicating, individual conditioning factors had an importance in influencing gully erosion. Slope (43%) and soil lithotype (25%), most influenced gully susceptibility, while land cover/land use (12%) and rainfall (12%) had least impact. Verification results showed satisfactory agreement between susceptibility map and field data on gullied areas at approximately 76.2%, an error of positive value of 4% and a negative value of 7%. Thus, production of susceptibility map by bivariate statistical method represents a useful tool for ending long and short-term gully emergencies by planning conservation of semi-arid regions.

Insecticidal potency of mixtures of plant powders and Actellic SuperTM (Pirimiphos-methyl + Permethrin) on Callosobruchus chinensis F. and Sitophilus zeamais Motch

Insect pests still cause substantial quantitative and qualitative grain loss ranging from 20 to 100% in small holder farming systems in tropical countries. Synthetic pesticides are recommended as stop gap measures for the management of stored product insect pests. However, their application has not been fully exploited in small scale farming due to environmental, health, and economic concerns. As a result, new researches have shifted focus to exploiting pesticidal plants as alternatives to synthetic pesticides. Therefore, the current study evaluated mixtures of plant powders and reduced amount of Actellic superTM (pirimiphos-methyl + permethrin) as alternative insecticide formulation against Callosobruchus chinensis and Sitophilus zeamais. Green grams and wheat grains were mixed with a mixture of plant powders in the ratios of 1:1, 1:3 and 1:9 to obtain four rates (0.0, 2.0, 6.0 and 10%w/w). Grains and plant powders were also mixed with reduced amount (10, 25, and 50 %) of recommended rate of Actellic SuperTM to obtain dosages as above. Twenty unsexed adults, 1-5 day old S. zeamais and C. chinensis were introduced into treated grains. The mixture of C. lusitanica: T. vogelii powders in the ratios of 1:1, 1:3 and 1:9 caused mortality in C. chinensis of 55, 95 and 85%, respectively. At the same ratio, E. saligna: L. camara mixture produced mortality in S. zeamais of 77, 82, and 85% respectively. In mixture of C. lusitanica and T. vogelii and reduced amount of Actellic SuperTM by 50% the mortality of C. chinensis was 85 and 80 % respectively. Similarly, E. saligna and L. camara and reduced amount of Actellic SuperTM by 50% caused a mortality of S. zeamais of 48 and 97% respectively. The application of plant powders and reduced amounts of synthetic insecticide has the potential to be applied in stored product pest control

Seroprevalence and risk factors of Neospora caninum and Bovine Viral Diarrhoea Virus in smallholder dairy cattle in Kenya

Little is known of the risk factors associated with occurrence of Neospora caninum and Bovine Viral Diarrhoea Virus (BVDV) infection in Kenya. This cross-sectional study hypothesized that there are significant biosecurity measures associated with N. caninum and BVDV infections on smallholder dairy farms in Kenya that could be adopted to reduce seroprevalence and impacts. From 158 randomly selected farms in Meru County, Kenya, 470 serum samples were collected from dairy cattle (over six months of age and unvaccinated for these two pathogens). Sera were analyzed for antibodies to N. caninum and antibodies and antigens to BVDV. Data on risk factors were obtained through face-to-face interviews with the farmers. Multivariable logistic regression models were used to identify significant risk factors associated with seropositivity for the pathogens. The apparent seroprevalence of N. caninum, BVDV antibody, BVDV antigen, and co-infection with N. caninum and BVDV antibody and/or antigen were 35.1%, 47.1%, 36.2% and 18.5%, respectively. Risk factors associated with N. caninum antibody included: introducing milking cows into the farm, lending of cattle between farms, farm dogs having access to bovine aborted fetuses, and dogs whelping in the farm compound, with an interaction between the last two variables. BVDV antigen was associated with cattle having contact with pigs, and an interaction between cattle age and whether farms introduced new calves onto farms, and cattle age and whether visiting dairy farmers have access to the cow shed. Cows had higher odds of having BVDV antibodies compared to heifers. Factors associated with co-infection included cow parity, direct contact between dairy cattle, dogs and goats, and introducing new milking cows into the farms. Antibody and antigen results may be partly a function of classical swine fever virus or border disease virus interactions. Farmer education on these biosecurity measures is recommended, along with introduction of BVDV vaccination.

Molecular detection of Campylobacter species from human and cattle faecal samples in Kilosa District, Tanzania

A growing number of Campylobacter species other than C. jejuni and C. coli have been considered as emerging human and animal pathogens but their contribution to human gastroenteritis is poorly documented. This study aimed at detecting Campylobacter species from human and cattle faecal samples in Kilosa District, Tanzania using molecular techniques without culture. Seventy (70) faecal samples were collected from five diarrheic and 65 non-diarrheic human patients attending Kilosa District Hospital in Tanzania from July to October 2019. During the same period, 30 faecal samples were also collected from healthy cattle in the same district. Genus and species identification of Campylobacter was conducted on the samples using molecular techniques [the polymerase chain reaction (PCR) and 16S rRNA sequencing]. Phylogenetic analysis was carried out by comparison of the 16S rRNA gene sequences to reference strains by the Neighbor-Joining method in MEGA X. Campylobacter species detection rate by PCR was 65.7% (46/70) and 20% (6/30) in humans and cattle, respectively. There were five human diarrheic cases, four of which were positive for Campylobacter and of these, two were children ≤15 years of age. In humans, 16S rRNA sequencing revealed that C. concisus was the most predominant species occurring at a frequency of 37.8% (14/37), followed by uncultured Campylobacter spp. 24.3% (9/37) and C. hominis 21.6% (8/37). The least represented species were C. jejuni and C. lanienae, all occurring at 2.7% (1/37). In cattle, five (100%) sequenced PCR products matched with C. lanienae. Phylogenetic analysis revealed that with the exception of C. lanienae, 16S rRNA sequences of Campylobacter species were closely related to the reference strains used (Percent identity: 90.51-96.56%). Based on our findings, we recommend that molecular techniques, mainly PCR be adopted for the direct detection of Campylobacter species during laboratory screening and surveillance studies.

Spatiotemporal characteristics of smallholder milk production under changing climate: A case of Nandi County, Kenya

Milk production in Kenya is predominantly smallholder and dependent on rainfall. The study assesses spatiotemporal characteristics of smallholder milk production in Nandi County under changing climate. Climate (Rainfall and temperature), fodder availability (Normalized Difference Vegetation Index (NDVI) and soil moisture content) and milk production data were used. Methods included trend analysis, spatial plots, correlation and multi-regression analysis. Monthly NDVI and soil moisture content were high between April and November with seasonal analysis indicating highest/lowest June-August (JJA)/December-February (DJF) values. Percentage change (%Δ) for NDVI was 6.0% (DJF), 1.96% (March-May, MAM), 2.13% (JJA), 4.16% (September-November, SON) and (2.53% (Annual). Seasonal and annual %Δ for soil moisture content ranged 7.2-17.1% at 0-10cm level and 8.1-23.7% at 10-40 level. Trend analysis of milk production showed positive change from 2007 to 2016 and highest/lowest in December/April with seasonal %Δ of up to 186% (MAM), 183% (JJA), 202% (SON), 214% (DJF) and 204% (Annual). Majority of household (HH) owned between 1 and 20 acres of land with only 0.5 to 2 acres allocated to dairy farming while those allocating less than 1 acre practiced zero grazing. On average, HH had 2 lactating cows throughout the year with majority of dairy farmers (98.6%) owning improved cow breeds. Amount of milk per HH supplied to the farmer organization varied between 2.3 litres and 3.8 litres with computed daily average milk produced per HH being 18.8 litres. Active milk suppliers were highest/lowest in December/April whereas daily average milk production per HH between 2010 and 2016 was highest/lowest in January (23.7 litres)/August (15.6 litres). Lowest/highest correlation coefficients were found in precipitation/minimum temperature. Multi-regression analysis indicated that precipitation had significant contribution to dairy productivity. Given the sensitivity of milk production to climate and fodder availability, adequate adaptation and mitigation measures are necessary in order to sustainably enhance milk production.

Flood-risk vulnerabilities of sanitation facilities in urban informal settlements: Lessons from Kisumu City, Kenya

Flood disasters have increased in frequency and severity over the recent decades causing untold destruction to vulnerable physical infrastructure such as sanitation facilities. Factors including construction quality, design, siting, and users’ behaviour further exacerbate the vulnerability of facilities. Despite this reality, very little has been done to document the extent of flood risk facing such facilities in the pro-poor urban informal settlements in developing countries. This study assessed the flood risks of vulnerable sanitation facilities in the urban informal settlements of Kisumu city, Kenya. The methodology involved assessment of sanitation facilities’ flood vulnerabilities and assessment of flood risk models. Flood risk was assessed by estimating runoff from yearly rainfall totals and also by calculating storm return period and probability of exceedance. Vulnerability assessment for each sanitation facility was done by scoring against flood risk indicators ordered by weighted rank. The study observed that majority sanitation facilities in the urban informal settlements were considered “highly vulnerable” (57%). Flood risk analysis predicted growing vulnerability due to shorter storm return periods, especially under the RCP 8.5 scenario. It was established that over 20% of all rainfall events in the 50-year timeline had a higher than 80% probability of exceedance rainfall, signifying higher storm risks. Additionally, the study showed that between 44% of rainfall received in the study area could translate to runoff, in the near future, further compounding flood risk predictions. With key informal settlements such as Nyalenda and Manyatta facing stronger future flood risks, general public health may be threatened, leading to increased social and economic instability on families and households. The study recommends adherence to improved toilet standards of construction and toilet-raising as methods of improving flood risk resilience and adaptation.

Randomised controlled trial on estrus and conception impacts of reproductive and nutrition interventions on Kenyan smallholder dairy farms.

This field trial tested the hypothesis that providing Kenyan smallholder dairy farmers with training and resources can enhance cows’ cyclicity and conception using conventional or sexed semen. One hundred farmers were randomly selected and randomly allocated to five equal-sized intervention groups: 1) reproduction only; 2) nutrition only; 3) reproduction and nutrition; 4) education only (quasi-control); or 5) nothing (control). Reproductive interventions included provision of prostaglandin F2? (PG) and/or gonadotropin-releasing hormone (GnRH) to induce estrus, and reproduction education. Nutrition interventions included provision of leguminous shrubs and nutrition education. At monthly visits over 17 months, farm and cattle data were collected, and open cattle underwent physical and reproductive exams to determine readiness for farmer decisions on sexed semen utilization. Cox proportional hazards modeling (CoxPH) was used to determine if intervention group was significantly associated with risk of conception. The final dataset included 191 cows and 26 heifers. Lowest and highest heat submission percentages were 8.5% and 35.5% in the control and reproduction groups, respectively. Conception percentages in cows and heifers were 44.0% and 54.5% for sexed semen and 72% and 79% for conventional semen, respectively. In the final multivariable CoxPH model, each unit increase in average body condition score was associated with 3.5 times higher risk of conception. Cattle that were inseminated following spontaneous heat had 1.8 times higher risk of conception over cows that were inseminated following a hormone-induced heat. In a significant interaction variable, when cows were supplemented with dairy meal in the last month of gestation, a higher risk of conception was achieved in cows on groups where leguminous shrubs were fed compared to groups where no leguminous shrubs were fed. This study concludes that focused effort on improving reproduction through education, hormone use and improved nutrition can improve heat submission and conception percentages on Kenyan smallholder dairy farms.

Characterization and pathogenicity of symbiotic bacteria associated with entomopathogenic nematode: Steinernema species KALRO

The soil inhibiting entomopathogenic nematodes (EPNs), in the family Steinernematidae and Heterorhabditidae, are useful insect biological control agents. They have been used in the management of economically important crop pests. The EPNs are mutually associated with symbiotic bacteria genus Xenorhabdus and Photoharbdus respectively. The study aimed to isolate, characterize and evaluate the pathogenicity of symbiotic bacteria associated with EPN Steinernema sp. Kalro (Accession MW151701). The EPN Steinernema sp. Karlo was multiplied using the insect baiting technique. Its bacteria symbiont was isolated and characterized based on microscopic, biochemical, and physiological features like Gram staining, urease, motility test, and glucose fermentation test). Molecular identification and phylogenetic analysis were performed on 16S rDNA nucleotide sequence. Pathogenicity of the bacteria isolate was evaluated against Tuta absoluta larvae with mortality data recorded after 24 and 48hours of exposure to the bacterial cell suspension. The bacteria were found to be motile and glucose fermentation positive. Sequence analysis of 16S rDNA region resulted in 1500bp sequence with maximum similarity of between 97 and 98.93%, with Xenorhabdus spp Accessions from Genbank. It closely matched to Xenorhabdus sp. My8NJ with 98.93% similarity (Accession AB507811.1). Mean percent larval mortality of 68±4.9 and 88±8.0 in the lowest cell suspension was observed in 24 and 48h of exposure. It’s concluded that, the symbiotic bacteria associated with Steinernema sp. Kalro is Xenorhabdus sp. strain Kalro Genbank Accession MW245845. The bacteria is a potential biological control agent against Tuta absoluta larvae. Further classification of the bacteria to species level and pathogenicity trials in the screen house and field are recommended.

Toward improving household livelihoods using rain water harvesting technologies in Matungulu sub-county, Machakos, Kenya

Better utilization of rainfall through rainwater harvesting can greatly increase agricultural productivity, improve food security and alleviate poverty. Water is the main limiting resource for crop production in arid sub-Saharan Africa. The biggest challenge currently is growing water shortage and dwindling rivers. This has impacted the livelihoods of rural population in arid and semi-arid counties. The introduction of novel rain-water harvesting (RWH) is, however, seeking to mitigate the effects of perennial droughts in arid areas. Successful adoption of such technologies has the potential to alleviate water problems faced by rural households. In Kenya, very little research has been conducted about adoption of water harvesting technologies and their role in curbing water shortages. Therefore, there was a need to interrogate the extent to which adoption of water harvesting technologies has impacted households in Matungulu Sub-County. Focus group discussions, interview with key informants, and structured questionnaires were used to collect data for the study which were then analyzed using SPSS version 22 software. The findings indicated that overall, a composite mean of 4.04 and a standard deviation of 0.699 of the respondents agreed that incentives from the county government significantly promoted water harvesting technologies. This was confirmed by a positively strong and significant correlation between the integration of RHT in the county development agenda and the impact on household livelihoods. A further regression analysis indicated that Integration of RHT had a positive and significant influence on household livelihoods (β= 0.755, t=22.351, p=0.000<0.05). Results of this survey indicate that rainwater technologies are financed mostly by household heads and county government initiatives have not been adequately felt. There is a strong indication from the study that water harvesting technologies had a statistically significant influence on the impact on household livelihoods. To ensure sustainability of rainwater harvesting technologies, the study recommends that Machakos

Antibiotic profile of Staphylococcus aureus and Coagulase negative Staphylococci species isolated from raw camel milk from Garissa County, Kenya

The emergence of multidrug resistant bacteria in clinically challenging situations is a global concern. Staphylococcus resistance poses a threat to available therapeutic agents in management of camel diseases. S. aureus is often isolated from mastitic camel milk. Coagulase negative Staphylococcus (CoNS) can be pathogenic in humans and animals. This cross-sectional study investigated the antimicrobial resistance phenotypes of Staphylococci species in raw camel milk from Garissa County, Kenya. A total of 231 raw camel milk samples from healthy camels were collected. Disk diffusion was used to determine antimicrobial susceptibility of the isolates. Bacteria were revived in Buffered Peptone Water (BPW). Staphylococcus isolates were cultured on Mannitol Salt agar (MSA) and Blood Agar (BA). Coagulase and catalase tests were used to biochemically characterize the isolates. Antibiotic disks were placed on Mueller Hinton Agar and incubated at 37°C for 24 hours and diameters of zones inhibition measured. The readings were recorded as either susceptible, intermediate, or resistant based on the interpretative breakpoints by the veterinary Clinical Laboratory Standards Institute (CLSI) guidelines. Antimicrobial agents tested included; Ampicillin, Streptomycin, Cephalexin, Erythromycin, Ciprofloxacin, Cefoxitin, Tetracycline and Chloramphenicol. Out of the 231 raw camel milk samples cultured, 52.8% (122/231) Staphylococci isolates were recovered. Among the Staphylococci isolates 83.6% (102) were S. aureus and 16.4% (20) were CoNS. Overall, 83 (68%) isolates were catalase positive and 122 (91.7%) showed β-haemolysis on BA culture. Highest resistance was observed against Cephalexin (81.9%) and Streptomycin (72.1%) while the lowest resistance was seen against Chloramphenicol (1.6%) and Tetracycline (3.3%). MRSA and MRCoNS were reported at 9.8% and 15% of the isolates respectively. MDR was recorded in 43.4% of the isolates resistant to at least 3 or more antimicrobial groups while 39.3% isolates were resistant to 1 or 2 antimicrobial tested. In conclusion, the study showed that CoNS and S