Red Maasai Research Articles

Evaluation of the current situation of sheep production characteristics in Nkasi District, Tanzania

Abstract. Kapongo RY, Mbaga SH. 2024. Evaluation of the current situation of sheep production characteristics in Nkasi District, Tanzania. Intl J Trop Drylands 8: 44-57. This study was conducted in two divisions, Namanyere and Mkwamba of Nkasi District in the Rukwa Region, Tanzania, to assess the sheep production status of smallholder farmers. Eight wards, namely Namanyere, Mtenga, Chala, Swaila, Kipande, Sintali, Kate, and Isale, were surveyed from November 2010 to April 2011. The random sampling technique was adopted to get 20 respondents from each selected ward. Two villages from each ward were chosen randomly, whereby ten respondents were interviewed in each village. A structured questionnaire was used to collect data from smallholder farmers keeping sheep and was complimented by secondary data from the district council offices. The results showed that sheep strains kept mainly by smallholder farmers were variant crosses of local strains and Red Maasai. The strains were deemed tolerant to diseases/parasites, heat, and drought and had better carcasses. Most smallholder farmers adopted an extensive grazing system during both dry and wet seasons. Breeding was uncontrolled; however, rams were selected based on their body sizes, conformation, and performance (e.g., number of lambs per ewe's lifetime, age at first lambing, and lambing intervals). Traits such as disease tolerance, drought, and heat tolerance scored higher for most strains. The average age at first lambing was 6.5 months, the lambing interval was three months, and the average number of lambs per ewe's lifetime was 14. The constraints to sheep production mostly were poor market availability, endemic diseases, and mortality of lambs. On marketing, fewer sheep were sold in the market compared to goats, and the price was 22% lower than that of goats.

Relative palatability and preference of sorghum silage, moringa or sesbania leaf meals by red Maasai sheep

Relative palatability and preference of sorghum silage, moringa or sesbania leaf meals by red Maasai sheep

Husbandry and Productivity of Red Maasai Sheep in Arumeru and Monduli Districts in Tanzania

This study was undertaken to describe the husbandry practices and productivity of the Red Maasai sheep in Arumeru and Moduli districts in Tanzania. Sixty three farmers from each of the two districts were interviewed. Data were analysed using SPSS computer package. All farmers (100%) practice an extensive production system where sheep graze together with cattle and goats. The majority (61.9%) of the farmers use communal land to graze their animals, and children are the main source (69.0%) of labour. Almost half (50.8%) of the farmers indicated to supplement their sheep with mainly (65.6%) maize bran. Identified constraints to production were diseases, drought, lack of capital, poor markets and extension services, thefts, and predators. A plastic apron was found to be an effective indigenous technique to control mating and practice seasonal breeding. Age at first lambing for the majority of Red Maasai sheep was 13 to 18 months and lambing intervals of 12 to 18 months. Most sheep lambed between October and January. Twinning cases were few (15.9%) indicating a low twinning rate in the population. Breeding rams were selected within flocks, and many farmers (95.2%) preferred seasonal breeding to allow ewes to lamb in the wet season. Disposals were done to get income, remove infertile ewes, and slaughter for food and rituals. Generally, the productivity of Red Maasai sheep was low due to poor husbandry practices. It was concluded that improved management was likely to enhance sustainable production and conserve the breed.

Phenotypic Characteristics of Red Maasai Sheep in Arumeru and Monduli Districts in Tanzania

Phenotypic Characteristics of Red Maasai Sheep in Arumeru and Monduli Districts in Tanzania

Impact of Haemonchus contortus infection on feed intake, digestion, liveweight gain, and enteric methane emission from Red Maasai and Dorper sheep

A study was conducted with Red Maasai and Dorper lambs to evaluate the effects of infection with the gastrointestinal nematode (GIN) Haemonchus contortus on feed intake, liveweight gain (LWG), feed energy and nitrogen partitioning, and enteric methane (CH4) emissions. Six- to seven-month-old Red Maasai (n=12) and Dorper (n=12) lambs were randomly allocated to three treatments (n=8, four lambs per breed) in a 2×3 factorial cross-over study over two periods (P1 and P2) of 36 days each. The treatments consisted of three combinations of GIN infection and feeding level: Infected + ad libitum feeding (I-adlib), uninfected + ad libitum feeding (Un-adlib), and uninfected + restricted feeding (Un-restd), across the two breeds. Lambs in the I-adlib group were trickle-infected daily with 1,000 L3 stage larvae of H. contortus for four consecutive days (Days 1–4), whereas lambs in the other experimental treatments were kept GIN free. The feed intake was measured daily. Liveweight (LW), faecal egg counts (FEC), and packed cell volume (PCV) were measured on Day 1 and weekly thereafter. On Days 29–33 total faecal and urine outputs were determined in metabolic crates. The lambs were then housed in respiration chambers for three consecutive days (Days 34–36). There was a washout period of 21 days before P2 started. Uninfected lambs (Un-adlib and Un-restd) had undetectable FEC throughout the study. On Day 36, FEC did not differ between the breeds (P>0.05). Infected lambs (I-adlib) had lower PCV than uninfected (Un-adlib and Un-restd) lambs on day 36. Neither breed nor infection influenced feed and nutrient intake, but as expected, restricted-fed lambs had a lower intake (P<0.05). The LWG of Un-adlib lambs was significantly higher than that of I-adlib and Un-restd lambs (P<0.05), whereas there was no breed difference (P>0.05). Neither breed nor infection affected feed digestibility, nitrogen retention or energy metabolisability (P>0.05). However, feed restriction decreased feed intake, LWG and N retention, whereas feed digestibility and energy metabolisability were unaffected. Neither daily CH4 emissions nor yield (per unit of feed intake) were affected by experimental infection, but Un-restd lambs had lower CH4 emissions per day. Red Maasai lambs had consistently lower daily CH4 emissions and yields than Dorper (P<0.01). This study confirmed the relative resistance of indigenous sheep (Red Maasai) to H. contortus infection, but the increased CH4 emission and yield due to GIN observed in other studies was not confirmed. Further investigations are needed to test whether in environments with multiple stress factors, local or indigenous breeds or their crossbreeds with exotic breeds may be better equipped to sustain production and simultaneously have a reduced carbon footprint than purebred exotic breeds.

On-station comparative analysis of reproductive and survival performance between Red Maasai, Dorper, and Merino sheep breeds.

The reproductive performance of ewes and the survivability of lambs to weaning have a critical economic impact on sheep farming worldwide. Further, knowledge of major mortality causes allows an opportunity for improved flock management to evade financial losses. The maximum likelihood estimates for generalised linear mixed models and chi-square test methods were used to examine 971 mating records, 839 and 763 lambs born and weaned (singles or twins) from the Naivasha Sheep and Goats station in Kenya for the years 2011 to 2020 consisting of Dorper, Red Maasai (RedM), and Merino breeds. The RedM (P<0.05) outperformed Dorper and Merino in weaning rate, whereas reproductive performance between the three breeds was not significantly different (P>0.05) in litter size and multiple lambings per ewe lambing. On the one hand, Dorper significantly (P<0.05) outperformed the other two breeds only in weaning weight per lamb born. In addition, among all the major causes of death, pneumonia appeared to be the one to which Dorper breeds were most susceptible (chi-square test, P<0.05). According to the findings of this study, neither the Dorper nor the Merino sheep breeds were reproductively superior to the RedM in an extensive semi-arid production environment. In addition, Dorper's susceptibility to the leading causes of mortality, particularly pneumonia and sheep pox, were relatively high compared to other breeds and could be a precursor to massive economic losses for Dorper sheep producers. In contrast to the indigenous RedM breed, imported sheep breeds appeared to be more susceptible to major mortality-related under an extensive production system. Therefore, regardless of weaning weight, RedM breed production appears to be a more viable investment for small-scale farmers, particularly in semi-arid regions.

An On-Station Analysis of Factors Affecting Growth Traits of Pure Red Maasai and Dorper Sheep Breeds under an Extensive Production System.

This comparative study aimed to evaluate genetic and environmental factors' effects on the growth traits of lambs in Dorper and Red Maasai (RedM) sheep breeds. The data analyzed contained the following measurements: birth weight (Bwt), weaning weight (Wwt), yearling weight (Ywt), birth type (single or twins), and details on each lamb's dam (dam ID and age) and sire. Except for the RedM, whose birth weight decreased with time, both breeds generally showed an increase in other growth weights across the study period, with yearly variations affecting both breeds. Additionally, analysis by a linear mixed model with restricted maximum likelihood (REML) showed that only breed as a factor significantly (p &lt; 0.05) influenced birth weight; breed, sex, and birth type all significantly (p &lt; 0.05) influenced weaning weight, whereas season, sex, and dam age significantly (p &lt; 0.05) influenced yearling weight. The RedM breed outperformed the Dorper breed in post-weaning growth rate, demonstrating early resilience and adaptation to local environmental factors independent of maternal influence. Breed and non-genetic factors play a vital role in the growth of lambs, and the results of this study offer an opportunity for improved farm management under an extensive production system and selection for the conservation of the indigenous Red Maasai breed.

Impacts of climate-smart crop varieties and livestock breeds on the food security of smallholder farmers in Kenya

This paper analyses the impact of climate-smart agriculture (CSA) technologies on household dietary diversity and food insufficiency as indicators of food and nutrition security in Kenya. Using a combination of Propensity Score Matching and endogenous treatment effect approaches, we found that adoption of stress-tolerant varieties of several crops (such as bean, pigeon pea, cowpea, maize and sorghum) improved household dietary diversity score by 40% and reduced food insufficiency by 75%. Adoption of improved and resilient livestock breeds (including Red Maasai sheep and Galla goats) improved household dietary diversity by 38% while reducing household food insufficiency by 90%. We also found that stress-tolerant crop varieties were more effective in improving food security outcomes among households with large landholdings and with more educated and younger to middle-age heads. Effects of resilient livestock breeds on household food security were much stronger for households with large landholdings and with young and/or much older heads that have low levels of education. Given the large, demonstrated benefits from the use of the CSA technologies, policies and programs aimed at their promotion should apply appropriate targeting to ensure wider uptake of the technologies and maximum returns on investment.

Genetic parameters and genetic trends for growth traits of the Red Maasai sheep and its crosses to Dorper sheep under extensive production system in Kenya

The Red Maasai are indigenous sheep breeds known for their adaptability in arid and semi-arid environments while the Dorper is known for its good mutton production. A field experiment cross breeding program for the two breeds was set up in 2003 to exploit these traits. In this paper, we present the genetic parameters for birth weight (BWT), weaning weight (WWT) and weight at nine months (MWT) for pure Red Maasai (RRRR), pure Dorper (DDDD), 75% Dorper (DDDR) and 50% Dorper (DDRR) breeds. The genetic parameters were estimated by fitting four different multivariate animal models while ignoring or including maternal effects. The model with the lowest Akaike’s Information Criterion (AIC) was chosen as the best model for the estimation of genetic parameters. The average annual genetic gain of the studied traits for each breed group was estimated by regressing the estimated breeding values on year of birth. Records from 5442 lambs recorded over a period of 17 years (2003-2019) were used in this analysis. The breed group, sex, type of birth, season of birth and age of the dam significantly (P < 0.001) affected the weights of the animals. The direct heritability estimates for BWT, WWT and MWT were highest in the RRRR (0.40 ± 0.08, 0.39 ± 0.08, 0.45 ± 0.08 respectively). Direct heritability was lowest for BWT in the DDDR (0.18 ± 0.06), and for WWT and MWT in the DDDD (0.10 ± 0.07, 0.08 ± 0.06 respectively). The maternal heritability estimates were highest in BWT for DDRR (0.12 ± 0.05) and at WWT for DDDD (0.05 ± 0.03), and lowest in BWT for DDDR (0.03 ± 0.03) and at WWT for DDRR (0.00 ± 0.01). The maternal heritability for MWT for all the breed groups was close to zero. Genetic and phenotypic correlations between the traits were all high and positive across all breed groups. The phenotypic correlations ranged from 0.41 to 0.73 while the genetic correlations ranged from 0.40 to 0.99. The pure Red Maasai had an average annual genetic gain of 0.012 ± 0.005 kg, 0.144 ± 0.037 kg and 0.170 ± 0.047 kg for BWT, WWT and MWT respectively while the pure Dorper had an average annual genetic gain of 0.006 ± 0.006 for BWT, 0.047 ± 0.033 for WWT and 0.069 ± 0.044 for MWT. Between the crosses, the 50% Dorper had higher annual genetic gains for all the traits. The observed genetic gains demonstrate that selective breeding based on estimated breeding values can lead to significant genetic improvement in the Red Maasai sheep and its crosses.

PSVIII-1 Genetic characteristics of Karachaev sheep inferred from genome-wide SNP analysis

Abstract Karachaev sheep is a fat-tailed breed from North-Caucasus, Russia. It has good adaptability to local environments and excellent meat quality. The aim of our study was to investigate genetic characteristics of Karachaev sheep and its relationship with other fat-tailed breeds. Samples of Karachaev (n = 22), Lezgin (n = 21), Edilbai (n = 21), Karakul (n = 21), Alai (n = 20), and Gissar (n = 20) breeds were genotyped using Ovine HD BeadChip. For phylogenetic analyses, we additionally included 50K genotypes of Afshari, Awassi, Barki, Chios, Cyprus Fat-Tailed, and Red Maasai breeds. PLINK 1.9 was used for quality control and performing PCA. Genetic diversity parameters were calculated in R package diveRsity. Historical effective population size (Ne) was estimated using SNeP 1.1. Cluster analysis was conducted in Admixture 1.3. TreeMix tree was constructed in TreeMix 1.13. Genetic diversity indices (observed and expected heterozygosity, allelic richness) were highest in Karachaev and Lezgin breeds. Karachaev sheep was phylogenetically closer to Lezgin and Edilbai breeds. Trends in historical Ne were very similar for these breeds. We observed the increased decline in Ne around 20–25 generations ago (which corresponds to 1940s) that can be associated with deportation of Karachaev people to Kazakhstan and Kyrgyzstan in 1943, which resulted in lost almost all of its livestock. TreeMix analysis allowing one migration event revealed gene flow from Karakul to Karachaev/Lezgin nod. Admixture analysis showed the presence in Karachaev sheep of Edilbai and Karakul specific genomic components (~80 and ~20%, respectively). Our study allow suggest that Karachaev breed was extinct during World War II and then was restored in 1960s after Karachaev people returned to their land. It originated from the sheep they brought from Central Asia (Edilbai), and was improved by Karakul breed and local sheep. This work was supported by RSF No. 21-46-00001 (genotyping) and the Russian Ministry of Science and Higher Education No. 0445-2019-0024 (expedition studies).

Adaptation and Returns from Improved Indigenous Small Ruminants in Climatically Challenged Smallholder Systems of Kenya

Improved climate-resilient strains of indigenous sheep and goats were introduced in the Nyando basin of western Kenya in 2013. This study evaluated the performance of the breeds five years after their first introduction, and their contribution to household revenues. Red Maasai and Red Maasai x Dorper sheep and Galla goats introduced in Nyando adapted to the environment and retained performance levels exhibited in their original environments. They have been widely adopted by the farmers and are used for upgrading local breeds through crossbreeding, yielding offspring that are 50% heavier than local breeds at one year of age. Costs for producing the small ruminants tend to increase with land size owned, mainly due to higher costs for managing the health of more livestock. The costs of producing goats are significantly higher than for sheep. Revenues accrued from goat milk contribute to 10% of the revenue from goats. The introduced breeds provided a significant productivity lift in the local livestock population, resulting in higher returns to the smallholder farmers. For long-term sustainability of the productivity gains, a community-based selective mating program using reference sire flocks with an overall goal of good growth, adaptability, and milk production should be adopted.

Prospects of use of genetic resources of sheep in Ukraine

Prospects of use of genetic resources of sheep in Ukraine

Staphylococcus aureus enterotoxin genes detected in milk from various livestock species in northern pastoral region of Kenya

Staphylococcus aureus (SA) food poisoning results from consumption of preformed S. aureus enterotoxins in food. The enterotoxins are one of the most important virulence factors of the bacterium. The risk posed by contamination of milk intended for human consumption by pathogenic S. aureus in pastoral areas in Kenya is still generally not well documented yet this information is critical for ensuring safety to consumers who sometimes may take unpasteurized milk. This study, therefore determined the prevalence of S. aureus enterotoxin genes in raw milk from cattle, goats, sheep and camels intended for human consumption in northern Kenya. A total of 603 milk samples from 57 zebu cattle, 346 galla goats, 8 red Maasai and dorper sheep, 4 one-humped camel (Camelus dromedaries) and 188 pooled from all animals were collected from Isiolo and Marsabit counties of Kenya. S. aureus isolates were cultured from milk samples using a selective media, mannitol salt agar (MSA). Suspect colonies of SA were further analyzed using biochemical tests. Polymerase chain reaction and sequencing techniques were used to confirm SA and detect sea, seb, sec, sed and see enterotoxin genes.Overall, potentially pathogenic S. aureus harboring enterotoxic genes were detected in 85 (14.09%, 95% CI: 11.55–17.1%) of the total milk samples. Genes encoding enterotoxins were detected in the S. aureus bacteria isolated from the milk samples. At least one type of S. aureus enterotoxin gene (SE) was detected in 74.11% (95% CI: 63.91–82.24%) of the 85 isolates. The most frequently encountered gene in the two counties was see (51; 60%, 95% CI: 49.73–69.76%) followed by sea (22; 25.88%, 95% CI: 17.76–36.09%) and sec (19; 22.35%, 95% CI: 14.8–32.29%). None of the isolates tested positive for sed. Overall, 21 of the 85 (24.7%, 95% CI: 16.76–34.83%) strains harbored more than one enterotoxin gene. More than half of the S. aureus isolates harbored at least one of the enterotoxin coding genes, indicating milk samples contaminated by S. aureus could have a high chance of causing staphylococcal food intoxication.Consumption of raw and sour milk in the region could increase the risk of staphylococcal food poisoning and pastoral communities in the region are therefore advised to consume pasteurized milk.

Assessment of OvineSNP50 in Nigerian and Kenyan sheep populations

Deciphering genomic information requires markers that are polymorphic and sufficient enough to capture its vast array of genetic data. Polymorphic loci can differ greatly between breeds of the same species and the exclusion of the Nigerian and some African sheep breeds during the development of the OvineSNP50 chip necessitated the validation of SNPs included on the chip to allow for genomic applications of the excluded breeds. A total of sixty sheep samples were genotyped [10 each of the Balami, Uda, West African Dwarf and Yankasa from Nigeria, Dorper and Red Maasai from Kenya (East Africa)] using the Ovine 50k Illumina SNP bead chip. Results revealed that 33,994 SNPs (97.47%) of the called 34,876 SNPs were validated for downstream analysis. Mean heterozygosity values of 0.154 and 0.153 were obtained for polymorphic SNPs on sex and autosomal chromosomes respectively, while the values of 0.662 and 0.054 were obtained on the sex and autosomal chromosomes respectively for the mean identity-bystate (IBS). Six and three individuals violated the per ID and identity-by-state (IBS) thresholds, respectively. It was observed that the Ovine 50k Illumina SNP bead chip was informative in the Nigerian and East African sheep that were studied, and should be useful in examining the underlying genetic variation. Keywords: Sheep, OvineSNP50, genome-wide, call rate, minor allele frequency

Purebreeding of Red Maasai and crossbreeding with Dorper sheep in different environments in Kenya.

The aim of this article was to study opportunities for improvement of the indigenous and threatened Red Maasai sheep (RM) in Kenya, by comparing purebreeding with crossbreeding with Dorper sheep (D) as a terminal breed, in two different environments (Env. A and a harsher Env. B), assuming different levels of genotype-by-environment interaction (G×E). Breeding goals differed between environments and breeds. Four scenarios of nucleus breeding schemes were stochastically simulated, with the nucleus in Env. A. Overall, results showed an increase in carcass weight produced per ewe by more than 10% over 15years. Genetic gain in carcass weight was 0.17 genetic SD/year (0.2kg/year) across scenarios for RM in the less harsh Env. A. For survival and milk yield, the gain was lower (0.04-0.05 genetic SD/year). With stronger G×E, the gain in the commercial tier for RM in the harsher Env. B became increasingly lower. Selection of females also within the commercial tier gave slightly higher genetic gain. The scenario with purebreeding of RM and a subnucleus in Env. B gave the highest total income and quantity of meat. However, quantity of meat in Env. A increased slightly from having crossbreeding with D, whereas that in Env. B decreased. A simple and well-designed nucleus breeding programme would increase the genetic potential of RM. Crossbreeding of RM with D is not recommended for harsh environmental conditions due to the large breed differences expected in that environment.

Live weight, conformation, carcass traits and economic values of ram lambs of Red Maasai and Dorper sheep and their crosses

Meat production is the most important trait in the breeding objectives of sheep production in East Africa. The aim of this study was to investigate breed differences in live weight, conformation, carcass traits and economic values for meat production among Red Maasai and Dorper sheep and their crosses. In total, 88 ram lambs, which were reared at the ILRI experimental station, Kapiti plains Estate in Central Kenya, were used for the study. The lambs were slaughtered at Kenya Meat Commission (KMC) at about 1 year of age. Prior to slaughter, the lambs were weighed, measured and assessed by experienced evaluators, and at the abattoir carcass traits were recorded. Large breed differences were found for most traits. Dorper lambs were heavier at delivery for slaughter and had better carcass grade but lower dressing percentage and fat levels than Red Maasai. Crossbreds were generally better than the parental breeds. Evaluators were willing to pay more for the Dorper lambs for slaughter although carcass weights later were shown not to be higher than for Red Maasai. Evaluators undervalued Red Maasai lambs by 8–13 % compared to Dorper lambs according to the prices quoted per kilogramme live or carcass weight by KMC. Live weight was better than any other live measure in predicting carcass weight. Due to the overall higher ranking of the crossbred lambs for meat production, Dorper may be useful as a terminal sire breed for crossing with Red Maasai ewes.

Participatory definition of breeding objectives for sheep breeds under pastoral systems--the case of Red Maasai and Dorper sheep in Kenya.

Crossing local breeds with exotic breeds may be an option for increased livestock productivity. However, there is a risk for endangerment of the local breeds. One such case is in Kenya where the imported Dorper breed is used for crossbreeding with Red Maasai sheep. The aim of this study was to investigate farmers’ trait preferences as a basis for determination of breeding objectives for Red Maasai and Dorper sheep at two sites, Amboseli and Isinya, in Kenya. Within their own flock, each farmer identified three ewes representing the best, average and poorest within each breed group: Red Maasai, Dorper and Crosses. Farmers gave reasons for their ranking. Body measurements and weights were also taken. At the harshest site, Amboseli, differences between breed groups in body weight were small and breeds were equally preferred. In Isinya, where environmental conditions are better and farmers are more market oriented, Dorper and Crosses had significantly higher body weights and market prices and were thus preferred by the farmers. Red Maasai were preferred for their maternal and adaptive traits. Breeding objectives should emphasize growth traits and milk production in both breeds at both sites. Body condition needs to be specifically considered in the breeding objectives for sheep in Amboseli, whereas adaptive traits need to be generally emphasized in Dorper.

Identification of novel loci associated with gastrointestinal parasite resistance in a Red Maasai x Dorper backcross population.

Gastrointestinal (GI) parasitic infection is the main health constraint for small ruminant production, causing loss of weight and/or death. Red Maasai sheep have adapted to a tropical environment where extreme parasite exposure is a constant, especially with highly pathogenic Haemonchus contortus. This breed has been reported to be resistant to gastrointestinal parasite infection, hence it is considered an invaluable resource to study associations between host genetics and resistance. The aim of this study was to identify polymorphisms strongly associated with host resistance in a double backcross population derived from Red Maasai and Dorper sheep using a SNP-based GWAS analysis. The animals that were genotyped represented the most resistant and susceptible individuals based on the tails of phenotypic distribution (10% each) for average faecal egg counts (AVFEC). AVFEC, packed cell volume (AVPCV), and live weight (AVLWT) were adjusted for fixed effects and co-variables, and an association analysis was run using EMMAX. Revised significance levels were calculated using 100,000 permutation tests. The top five significant SNP markers with - log10 p-values >3.794 were observed on five different chromosomes for AVFEC, and BLUPPf90/PostGSf90 results confirmed EMMAX significant regions for this trait. One of these regions included a cluster of significant SNP on chromosome (Chr) 6 not in linkage disequilibrium to each other. This genomic location contains annotated genes involved in cytokine signalling, haemostasis and mucus biosynthesis. Only one association detected on Chr 7 was significant for both AVPCV and AVLWT. The results generated here reveal candidate immune variants for genes involved in differential response to infection and provide additional SNP marker information that has potential to aid selection of resistance to gastrointestinal parasites in sheep of a similar genetic background to the double backcross population.

Assessing Sheep Traders’ Preferences in Kenya: A Best-worst Experiment from Kajiado County

This study investigates the purchase behavior of sheep traders in Kajiado County in Kenya. This is, to the best of our knowledge, the first investigation on sheep traders by the use of Best-Worst technique. A face-to-face questionnaire was undertaken in three livestock markets (Kiserian, Bissil and Mile 46) involving 108 traders. The results indicated that sheep traders are also involved in other types of animal trading, essentially cattle and goats. Income from sheep trading represents slightly less of the half of total incomes, with some differences between livestock traders’ groups (markets). Traders are generally involved in other business activities among the value chain essentially such as livestock production, fattening and slaughtering. Four attributes with different levels have been utilized to describe the Best-Worst experiment: sheep age, sex, breed and price. All sheep traders assign higher importance to the sheep breed. This is essentially the case of Dorper pure breed and Dorper x Red Maasai cross breed. Price attribute was the second most important factor for sheep traders with higher preferences for the two extreme price levels. Sheep age and sex were found of least importance for traders. Providing sheep smallholders with the appropriate animal breed characteristics will enable them match market demand and increase their incomes. This is one of tasks of ILRI Kapiti experimental farm.

Quantitative trait loci for resistance to Haemonchus contortus artificial challenge in Red Maasai and Dorper sheep of East Africa

A genome-wide scan was performed to detect quantitative trait loci (QTL) for resistance to the gastrointestinal nematode Haemonchus contortus in a double backcross population of Red Maasai and Dorper sheep. The mapping population comprised six sire families, with 1026 lambs in total. The lambs were artificially challenged with H. contortus at about 6.5 months of age, and nine phenotypes were measured: fecal egg count, packed cell volume decline, two weight traits and five worm traits. A subset of the population (342 lambs) was selectively genotyped for 172 microsatellite loci covering 25 of the 26 autosomes. QTL mapping was performed for models which assumed that the QTL alleles were either fixed or segregating within each breed, combined with models with only an additive QTL effect fitted or both additive and dominance QTL effects fitted. Overall, QTL significant at the 1% chromosome-wide level were identified for 22 combinations of trait and chromosome. Of particular interest are a region of chromosome 26 with putative QTL for all nine traits and a region of chromosome 2 with putative QTL for three traits. Favorable QTL alleles for disease resistance originated in both the Red Maasai and Dorper breeds, were not always fixed within breed and had significant dominance effects in some cases. We anticipate that this study, in combination with follow-up work and other relevant studies, will help elucidate the biology of disease resistance.