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1.
Sci Rep ; 14(1): 16342, 2024 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014189

RESUMO

Indigenous goats are important to many livelihoods. Despite this, they are subjected to indiscriminate crossbreeding. This affects their genetic variability which is needed to survive in current regime of climate change. The study assessed population structure and genetic diversity of Galla and Small East African goats (SEA) using pedigree information. A total of 7384 animals, 5222 of the Galla and 2162 of the SEA breeds, born between the years 1983 and 2022, were utilized. Individuals with known parents were defined as reference population. From the results, the maximum generation traced for Galla and SEA populations was 14.6 and 14.5, respectively. However, only 6 and 5 generations for Galla and SEA were complete. Pedigree completeness increased with the increasing number of generations. The average generation interval (GI) for Galla and SEA was 3.84 ± 0.04 and 4.4 ± 0.13 years. The average increase in the rate of inbreeding per generation for Galla and SEA was 0.04 and 0.05, with the effective ancestors and founders (fa/fe) ratio being same (1.00) for both breeds. Fifty percent (50%) of the genetic variability in the populations was contributed by 3 and 1 ancestor for Galla SEA, respectively. The effective population size (Ne) was 5.19 and 4.77 for Galla and SEA. Therefore, the current breeding programs should be changed to avoid future genetic bottlenecks in this population. These findings offer an opportunity to enhance the current genetic status and management of Kenyan native goats and other regions with similar production systems.


Assuntos
Variação Genética , Cabras , Animais , Cabras/genética , Quênia , Linhagem , Genética Populacional , Cruzamento , Endogamia , Masculino , Feminino , Densidade Demográfica
2.
Biology (Basel) ; 13(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38927299

RESUMO

Indigenous goats are important in the livelihoods of rural households in East African countries. This is due to their ability to produce and reproduce in different environments and climatic conditions. Even though these indigenous goats are important, there is little available information on the genetic characterization of these breeds in Africa and at the international level. This paper reviews the status of indigenous goats, highlighting their production systems, phenotypic and genetic characteristics, and genetic diversity, and proposes potential ways for sustainable improvement and conservation in East African countries. Most households use traditional production systems with various uncharacterized goat breeds and ecotypes, which are hence named after the tribe or locality in which they are found. Most of these goats are classified as small East African breeds, with significant variability in morphological features. Some of the challenges to goat production in this region are indiscriminate crossbreeding, lack of pedigree records, parasites and disease incidences, low-quality pastures, and low levels of management. There is a need for a collaborative approach amongst the actors in goat breeding value chains as well as integrating modern genomic tools into breeding programs to enhance selection. This will ensure the resilience and sustainability of these unique indigenous goat populations in East Africa.

3.
Heliyon ; 10(3): e25200, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38322857

RESUMO

It is arguable at this time whether climate change is a cause or effect of the disruption in dairy farming. Climate change drastically affects the productive performance of livestock, including milk and meat production, and this could be attributed to the deviation of energy resources towards adaptive mechanisms. However, livestock farming also contributes substantially to the existing greenhouse gas pool, which is the causal of the climate change. We gathered relevant information from the recent publication and reviewed it to elaborate on sustainable dairy farming management in a changing climatic scenario, and efforts are needed to gather this material to develop methods that could help to overcome the adversities associated with livestock industries. We summarize the intervention points to reverse these adversities, such as application of genetic technology, nutrition intervention, utilization of chemical inhibitors, immunization, and application of metagenomics, which may help to sustain farm animal production in the changing climate scenario.

4.
Biology (Basel) ; 12(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36979078

RESUMO

Dorper sheep was developed for meat production in arid and semi-arid regions under extensive production systems in South Africa. Two variants with distinct head and neck colors were bred during their development process. White Dorper have a white coat while Dorper have a black head and neck. Both variants have grown in popularity around the world. Therefore, understanding the genomic architecture between South African Dorpers and Dorper populations adapted to other climatic regions, as well as genomic differences between Dorper and White Dorper variants is vital for their molecular management. Using the ovine 50K SNP chip, this study compared the genetic architecture of Dorper variants between populations from South Africa and Hungary. The Dorper populations in both countries had high genetic diversity levels, although Dorper in Hungary showed high levels of inbreeding. White Dorpers from both countries were genetically closely related, while Dorpers were distantly related according to principal component analysis and neighbor-joining tree. Additionally, whereas all groups displayed unique selection signatures for local adaptation, Dorpers from Hungary had a similar linkage disequilibrium decay. Environmental differences and color may have influenced the genetic differentiation between the Dorpers. For their molecular management and prospective genomic selection, it is crucial to understand the Dorper sheep's genomic architecture, and the results of this study can be interpreted as a step in this direction.

5.
Saudi J Biol Sci ; 30(1): 103505, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36471796

RESUMO

Climate change has a significant effect on the productivity of livestock including milk, meat, and reproduction. This could be attributed to the internal diversion of energy resources towards adaptive mechanisms. Among the climate change variables, thermal stress seems to be the major limiting factor in animal agriculture. A better understanding of the effects of climate change-influenced ecological factors on the genetic diversity of livestock species is warranted. Sheep is an ideal livestock species to be used in investigating environmental adaptation due to its wide range of agroecological habitats, genetic and phenotypic variability. There is a heavy reliance on sheep genetic diversity for future animal protein security, but the implications of climate change on their genetic diversity receive less attention. Here, the potential environmental factors influencing natural selection in sheep populations are presented. We argue that prolonged exposure to these factors plays a major role in influencing the development of adaptation traits in indigenous sheep breeds, consequently leading to the alteration of genetic diversity at specific loci. The factors discussed include hot temperatures (heat stress), insufficient water, low quantity and quality of forage, and prevalence of parasites, pests, and diseases. In addition, genetic diversity, some signatures of selection for adaptation and economic angles of selection are also briefly discussed. A better understanding of environmental factors influencing the genetic diversity of sheep populations will inform breeding and management programs and may offer an opportunity for greater production efficiency with low input costs.

6.
Biology (Basel) ; 10(8)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34440042

RESUMO

The focus of this review is to offer an overview of food and nutritional security, to identify associated constraints, and propose possible alternative solutions for improving the East African poultry sub-sector in the pursuit of food security, focusing on chicken breeding. To better understand the prospects of the poultry industry, we highlighted and combined confirming evidence of the phenotypic variability and genetic diversity of East African chicken genetic resources using both morphological and molecular tools, as well as performance traits. Furthermore, this work gives a detailed indication of what would be lost if indigenous chicken populations are left to suffer the ongoing massive genetic erosions due to various factors, not limited to indiscriminate crossbreeding. Previous and recent attempts to improve the productivity of indigenous chicken are highlighted, and possible future breeding plans and areas of immediate research are suggested as well. This review concludes that under the prevailing conditions, the village chicken production system appears to be the most imperious production system that needs to be extensively developed ; however, for the sustainability of the industry, the proposed improvement strategies should create a permanent balance between the competing needs of genetic improvement and the genetic diversity of the indigenous chicken genetic resource.

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