104 research outputs found
Effect of Crossbreeding Indigenous Sheep with Awassi and Corriedale Sires on Reproductive Performance under Smallholder Production System in Ethiopia
The objective of this study was to evaluate the effect of crossbreeding on reproductive performance. A village based sheep crossbreeding project has been implemented since 1998 in three villages in the South Wollo, Menz and Chacha districts in Ethiopia. Crossbred rams (3/4 Awassi x 1/4 Local) were supplied to a group of farmers aiming to upgrading the indigenous genotype through backcrossing. The combined levels of location and genotype, year, season and parity had significant effects on the reproductive performance of ewes. Generally, local genotypes showed better (p<0.05) reproductive performance except for number of lambs weaned per ewe per year. The interaction of genotype and location was significant for age at first lambing and lambing interval. In Wollo, Corriedale x local crossbred ewes had similar reproductive performance to that of the local breed. The variation in reproductive performance among locations indicated the importance of delineating crossbreeding areas depending on environmental situation and farmers’ capacity
Cross-breeding cattle for milk production in the tropics: achievements, challenges and opportunities
This paper reviews experiences with cross-breeding for milk production in the tropics. Data were compiled from 23 different studies evaluating the performance of different grades of cross-bred animals as well as local breeds. Relative performance of indigenous breeds compared with different grades of cross-breeds was calculated for three climatic zones. Traits considered were milk yield per lactation, age at first calving, services per conception, lifetime milk yield and total number of lactations completed. At 50 percent Bos taurus blood, lactation milk yields were 2.6, 2.4 and 2.2 times higher than those of local cattle in the highland, tropical wet and dry, and semi-arid climatic zones, respectively; lactation lengths increased by 1.2, 1.2 and 1.9 months in the above-mentioned climatic zones, respectively; there was a reduction in calving interval by 0.8 times and in age at first calving by 0.9 times. Similarly, cross-breds with 50 percent B. taurus genes had 1.8 times higher lifetime milk yields and a 1.2 times higher number of total lactations. Although cross-breeding faces a number of challenges such as better infrastructure, higher demand for health care, there are many advantages of using it. These are higher production per animal, higher income for the families and provision of high-value food. It is therefore likely to continue to be an important livestock improvement tool in the tropics in the future, where farmers can provide sufficient management for maintaining animals with higher input requirements and access to the milk market can be secured
Guidelines for setting up community-based sheep breeding programs in Ethiopia: Lessons and experiences for sheep breeding in low-input systems
Genetic and morphological characterisation of the Ankole Longhorn cattle in the African Great Lakes region
The study investigated the population structure, diversity and differentiation of almost all of the ecotypes representing the African Ankole Longhorn cattle breed on the basis of morphometric (shape and size), genotypic and spatial distance data. Twentyone morphometric measurements were used to describe the morphology of 439 individuals from 11 sub-populations located in five countries around the Great Lakes region of central and eastern Africa. Additionally, 472 individuals were genotyped using 15 DNA microsatellites. Femoral length, horn length, horn circumference, rump height, body length and fore-limb circumference showed the largest differences between regions. An overall FST index indicated that 2.7% of the total genetic variation was present among sub-populations. The least differentiation was observed between the two sub-populations of Mbarara south and Luwero in Uganda, while the highest level of differentiation was observed between the Mugamba in Burundi and Malagarasi in Tanzania. An estimated membership of four for the inferred clusters from a model-based Bayesian approach was obtained. Both analyses on distance-based and model-based methods consistently isolated the Mugamba sub-population in Burundi from the others
Focus issue: pastoralism and rangelands in mountains
Mountain rangelands (open grasslands, mixed forest meadows, closed forests, and alpine lakes and wetlands) play vital roles for humans,
supporting livestock grazing, hunting, and harvesting of plants. They thus provide livelihoods for a large number of rural mountain communities
across the globe. These systems are also key for water supply to lowland areas and watershed health, carbon sequestration and storage, fire
regulation, and, increasingly, recreational use and tourism. They are vital for the conservation of mountain species and habitats, including
endemic species and habitats exclusive to mountains. Many of these ecosystems require management to maintain species diversity and productivity
and supply a range of high-quality ecosystem services.info:eu-repo/semantics/publishedVersio
Factors affecting fruit and vegetable consumption and purchase behavior of adults in sub-Saharan Africa:A rapid review
In order to achieve the Sustainable Development Goals, considerable dietary shifts, including an increase in the consumption of fruit and vegetables (FV) will be required. However, worldwide consumption of FV is far below international recommendations, including in many low- and middle-income countries (LMICs), particularly in Africa. Understanding what, where, when, and how people choose to eat requires an understanding of how individuals are influenced by factors in their social, physical, and macro-level environments. In order to develop effective interventions to increase fruit and vegetable consumption, the factors influencing consumer behavior need to be better understood. We conducted a rapid review to assess and synthesize data on individual, social, physical, and macro-level factors that enable or constrain fruit and vegetable consumption and purchase among adults living in sub-Saharan Africa. Our conceptual framework is based on a socio-ecological model which has been adapted to settings in LMICs and Africa. We systematically searched four electronic databases including Scopus, Medline (PubMed), PsycInfo, and African Index Medicus, and screened Google Scholar for gray literature. We included a total of 52 studies and narratively summarized the existing evidence for each identified factor across the different levels. We found that most studies assessed demographic factors at the individual level including household or family income, socio-economic status and education. Furthermore we identified a variety of important factors that influence FV consumption, in the social, physical, and macro environment. These include women's empowerment and gender inequalities, the influence of neighborhood and retail food environment such as distance to market and price of FV as well as the importance of natural landscapes including forest areas for FV consumption. This review identified the need to develop and improve indicators both for exposure and outcome variables but also to diversify research approaches
Dual-purpose cattle production in Nicaragua: Which breed fits best?
The importance of milk and beef production in Latin America is high and increasing. In Nicaragua
and neighbouring countries, smallholder dual-purpose (i.e., milk and beef) cattle production
offers opportunities for poor cattle owners to improve their food and nutrition security, and increase
their income. The milk and beef value chain employs thousands of people in production, processing
and marketing. In order to improve production, many farmers currently practice crossbreeding, involving
a large range of breed combinations, but without clear breeding strategies. To assess current
farmers´ practices and develop appropriate breeding and related management recommendations, a
research project that brings together the national agricultural university of Nicaragua (UNA), the
International Livestock Research Institute (ILRI), the International Center for Tropical Agriculture
(CIAT and BOKU-University is being implemented in two study sites in Central Nicaragua,
Camoapa and Matigu´as Municipalities. A gender-responsive baseline survey with questionnaires
was performed with 289 households in Camoapa and 252 in Matigu´as, using a random sampling
procedure based on official census data. A “paperless” data collection format was adopted using
the “Open Data Kit” (ODK) information technology platform.
Most households (>83 %) were male-headed in both municipalities. Mean age of the household
head was higher in Camoapa (51.4±14 years) than in Matiguas (48.9±14 years).
Most of the cattle reared in the two municipalities were cross-breds (>98 %). The crosses comprised
combinations between several breed-types. The most abundant breed-type in Matigu´as was
the Brahman, while in Camoapa there were more Brown Swiss and Holstein cross animals. At both
locations also other breeds such as Creole, Girolando, Jersey, Nellore, Reyna and Simmental were
found, whereas a large proportion of animals were crosses of unknown breed-types. Farmers stated
different reasons for using various breeds in their herds such as availability of semen or bulls or
different purposes for production. This is also reflected in the selection criteria of farmers. In comparison
to Matigu´as, cattle production in Camoapa is more intensive (higher number of animals per
hectare, stronger tendency towards dairy production), this probably being an effect of a stronger
presence of development organisations
The use of system dynamics modelling methodologies in sheep breeding programs and management systems
System dynamics modelling approach has been widely used in the agriculture sector to describe livestock production systems, livestock health and natural resource management. However, its application in modelling livestock breeding programs and systems is limited. Therefore, this study explores the utility of system dynamics modelling in evaluation of sheep breeding programs and management systems in the Ethiopian highland. A community-based sheep breeding programme was modeled using STELLA software. A weather and resource driven stochastic herd model was developed to evaluate the effect of genetic improvement and change in management system on herd dynamics and profitability. The baseline model was developed using historical rainfall and temperature data. Performance data was extracted from the herd-book of the breeding programme and additional input data were obtained from various sources. The model accounts for pasture growth, nutrient requirement and seasonal variation in animal performance, physiological status and aging chain of the herd. Economic analysis was also done considering the returns and costs of the system. The baseline model was further expanded to account for genetic selection of body size, fattening strategies and alternative management systems to evaluate their effect on herd dynamics and profitability. Technical evaluation and extensive logic testing during the building phases was conducted. The model results were compared to independent calculations to determine whether the model was matching expectations, and to help clarify the relationships between variables. The model demonstrates that balancing the feed supply and demand is crucial. Genetic selection for large body size has resulted in decrease of herd size and higher income. Fattening of young animals has increased the farm income. Increase feed supply by producing improved forage plants increased herd size and farm income. For more economic benefit genetic improvement programs should be coincide with appropriate fattening strategies and resource availability. Overall, system dynamics modelling tools are useful to describe breeding programs and management systems by building simple, flexible and usage driven simulation models
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