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Negash F, Abegaz S, Tadesse Y, Jembere T, Esatu W, Dessie T. Evaluation of reciprocal F1 crosses of Fayoumi with two exotic chicken breeds 1: additive and non-additive effects on egg production traits. Trop Anim Health Prod 2023; 55:303. [PMID: 37726577 PMCID: PMC10509068 DOI: 10.1007/s11250-023-03735-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 09/12/2023] [Indexed: 09/21/2023]
Abstract
The present study estimates additive and non-additive effects on egg production traits in genotypes generated through pure mating and reciprocal crossing of Fayoumi (FM) with Koekoek (KK) and White Leghorn (WL). Age at first egg (AFE) and body weight at first egg (BWAFE) were determined when the first bird in the pen laid its first egg, and egg weight at first egg (EWAFE) was the average weight of eggs laid consecutively during the first 10 days. Egg number (EN) and egg weight (EW) were recorded daily from AFE to 40 weeks of age. Egg mass (EM) was the product of EN and EW. EN of hens initially housed and hens alive during the experiment were used to calculate hen-housed egg production (HHEP) and hen-day egg production (HDEP), respectively. All the traits showed statistically significant differences among the genotypes. The results revealed the importance of additive and non-additive effects, where purebred effect (PE), general combining ability (GCA), maternal effect (ME), specific combining ability (SCA), and residual reciprocal effect (RRE) significantly affected most of the traits. The KK and WL had a higher PE, and GCA was highest in KK, with FM and WL showing a higher ME. The FM x WL had higher SCA and RRE. The KK x FM and FM x WL outperformed their main and reciprocal crosses, respectively, and purebred contemporaries. Therefore, a synthetic breeding program involving KK as a sire and FM, WL, FM x WL, and KK x FM as a dam would be feasible.
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Affiliation(s)
- Fikrineh Negash
- Adami Tulu Agricultural Research Center, P. O. Box 35, Batu, Ethiopia.
- School of Animal and Range Sciences, Haramaya University, P. O. Box 138, Dire Dawa, Ethiopia.
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, P. O. Box 2003, Addis Ababa, Ethiopia
| | - Yosef Tadesse
- School of Animal and Range Sciences, Haramaya University, P. O. Box 138, Dire Dawa, Ethiopia
| | - Temesgen Jembere
- Ethiopian Institute of Agricultural Research, P. O. Box 2003, Addis Ababa, Ethiopia
| | - Wondmeneh Esatu
- International Livestock Research Institute, P.O. Box 5689, Addis Ababa, Ethiopia
| | - Tadelle Dessie
- International Livestock Research Institute, P.O. Box 5689, Addis Ababa, Ethiopia
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Negash F, Abegaz S, Tadesse Y, Jembere T, Esatu W, Dessie T. Evaluation of reciprocal F1 crosses of Fayoumi with two exotic chicken breeds 2: additive and non-additive effects on egg quality traits. Trop Anim Health Prod 2023; 55:296. [PMID: 37723359 PMCID: PMC10506940 DOI: 10.1007/s11250-023-03728-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 09/12/2023] [Indexed: 09/20/2023]
Abstract
The current study evaluates additive and non-additive genetic variances for egg quality traits in six genotypes generated through pure mating and reciprocal crossing of Fayoumi (FM) with Koekoek (KK) and White Leghorn (WL). For each genotype, measurements were taken on 30 eggs randomly sampled at 32, 36, and 40 weeks of age to evaluate both external and internal egg quality parameters. The results revealed significant differences (P < 0.001) among the genotypes in all external quality traits and most internal quality traits, including yolk weight (YW), albumen weight (AW), and yolk height (YH). The results also showed that variations due to purebred effect (PE), general combining ability (GCA), maternal effect (ME), and specific combining ability (SCA) were significant in most traits, which reflects that both additive and non-additive variances are important for the inheritances of the parameters investigated. In most of the traits, the ME and PE were higher in KK and WL, while GCA was higher in KK and FM. The FM x WL had higher SCA than FM x KK. The results suggest the likelihood of genetic improvement in these genotypes through selection and crossbreeding strategies and/or a combination of the two.
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Affiliation(s)
- Fikrineh Negash
- Adami Tulu Agricultural Research Center, P. O. Box 35, Batu, Ethiopia.
- School of Animal and Range Sciences, Haramaya University, P. O. Box 138, Dire Dawa, Ethiopia.
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, P. O. Box 2003, Addis Ababa, Ethiopia
| | - Yosef Tadesse
- School of Animal and Range Sciences, Haramaya University, P. O. Box 138, Dire Dawa, Ethiopia
| | - Temesgen Jembere
- Ethiopian Institute of Agricultural Research, P. O. Box 2003, Addis Ababa, Ethiopia
| | - Wondmeneh Esatu
- International Livestock Research Institute, P.O. Box 5689, Addis Ababa, Ethiopia
| | - Tadelle Dessie
- International Livestock Research Institute, P.O. Box 5689, Addis Ababa, Ethiopia
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Woodward-Greene MJ, Kinser JM, Huson HJ, Sonstegard TS, Soelkner J, Vaisman II, Boettcher P, Masiga CW, Mukasa C, Abegaz S, Agaba M, Ahmed SS, Maminiaina OF, Getachew T, Gondwe TN, Haile A, Hassan Y, Kihara A, Kouriba A, Mruttu HA, Mujibi D, Nandolo W, Rischkowsky BA, Rosen BD, Sayre B, Taela M, Van Tassell CP. Using the community-based breeding program (CBBP) model as a collaborative platform to develop the African Goat Improvement Network-Image collection protocol (AGIN-ICP) with mobile technology for data collection and management of livestock phenotypes. Front Genet 2023; 14:1200770. [PMID: 37745840 PMCID: PMC10512022 DOI: 10.3389/fgene.2023.1200770] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 07/25/2023] [Indexed: 09/26/2023] Open
Abstract
Introduction: The African Goat Improvement Network Image Collection Protocol (AGIN-ICP) is an accessible, easy to use, low-cost procedure to collect phenotypic data via digital images. The AGIN-ICP collects images to extract several phenotype measures including health status indicators (anemia status, age, and weight), body measurements, shapes, and coat color and pattern, from digital images taken with standard digital cameras or mobile devices. This strategy is to quickly survey, record, assess, analyze, and store these data for use in a wide variety of production and sampling conditions. Methods: The work was accomplished as part of the multinational African Goat Improvement Network (AGIN) collaborative and is presented here as a case study in the AGIN collaboration model and working directly with community-based breeding programs (CBBP). It was iteratively developed and tested over 3 years, in 12 countries with over 12,000 images taken. Results and discussion: The AGIN-ICP development is described, and field implementation and the quality of the resulting images for use in image analysis and phenotypic data extraction are iteratively assessed. Digital body measures were validated using the PreciseEdge Image Segmentation Algorithm (PE-ISA) and software showing strong manual to digital body measure Pearson correlation coefficients of height, length, and girth measures (0.931, 0.943, 0.893) respectively. It is critical to note that while none of the very detailed tasks in the AGIN-ICP described here is difficult, every single one of them is even easier to accidentally omit, and the impact of such a mistake could render a sample image, a sampling day's images, or even an entire sampling trip's images difficult or unusable for extracting digital phenotypes. Coupled with tissue sampling and genomic testing, it may be useful in the effort to identify and conserve important animal genetic resources and in CBBP genetic improvement programs by providing reliably measured phenotypes with modest cost. Potential users include farmers, animal husbandry officials, veterinarians, regional government or other public health officials, researchers, and others. Based on these results, a final AGIN-ICP is presented, optimizing the costs, ease, and speed of field implementation of the collection method without compromising the quality of the image data collection.
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Affiliation(s)
- M. Jennifer Woodward-Greene
- National Agricultural Library, USDA Agricultural Research Service, Beltsville, MD, United States
- Animal Genomics Improvement Laboratory, USDA Agricultural Research Service, Beltsville, MD, United States
- Bioinformatics and Computational Biology Program, School of Systems Biology, College of Science, George Mason University, Manassas, VA, United States
| | - Jason M. Kinser
- School of Physics, Astronomy, and Computational Sciences, College of Science, George Mason University, Fairfax, VA, United States
| | - Heather J. Huson
- Department of Animal Science, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, United States
| | | | - Johann Soelkner
- Department of Sustainable Agricultural Systems, Division of Livestock Sciences, BOKU—University of Natural Resources and Life Sciences, Vienna, Austria
| | - Iosif I. Vaisman
- Bioinformatics and Computational Biology Program, School of Systems Biology, College of Science, George Mason University, Manassas, VA, United States
| | - Paul Boettcher
- Food and Agriculture Organization of the United Nations, Animal Production and Health Division, Rome, Italy
| | - Clet W. Masiga
- Association for Strengthening Agricultural Research in Eastern and Central Africa (ASARECA), Entebbe, Uganda
| | | | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Morris Agaba
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Sahar S. Ahmed
- Cell Biology Department, Biotechnology Research Institute, National Research Centre, Giza, Egypt
| | - Oliver F. Maminiaina
- Department of Zootechnical, Veterinary and Piscicultural Research (DRZVP), National Center for Applied Research in Rural Development (CENRADERU), Antananarivo, Madagascar
| | - Tesfaye Getachew
- International Center for Agricultural Research in the Dry Areas (ICARDA), Addis Ababa, Ethiopia
| | - Timothy N. Gondwe
- Department of Animal Science, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Aynalem Haile
- International Center for Agricultural Research in the Dry Areas (ICARDA), Addis Ababa, Ethiopia
| | - Yassir Hassan
- Department of Animal Genetic Resources Development, Animal Production Research Center, Ministry of Animal Resources, Khartoum North, Sudan
| | | | | | | | - Denis Mujibi
- International Livestock Research Institute, Nairobi, Kenya
| | - Wilson Nandolo
- Department of Animal Science, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Barbara A. Rischkowsky
- International Center for Agricultural Research in the Dry Areas (ICARDA), Addis Ababa, Ethiopia
| | - Benjamin D. Rosen
- Animal Genomics Improvement Laboratory, USDA Agricultural Research Service, Beltsville, MD, United States
| | - Brian Sayre
- Department of Biology, Virginia State University, Petersburg, VA, United States
| | - Maria Taela
- Agrarian Research Institute of Mozambique, Directorate of Animal Science, Maputo, Mozambique
| | - Curtis P. Van Tassell
- Animal Genomics Improvement Laboratory, USDA Agricultural Research Service, Beltsville, MD, United States
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Van Tassell CP, Rosen BD, Woodward-Greene MJ, Silverstein JT, Huson HJ, Sölkner J, Boettcher P, Rothschild MF, Mészáros G, Nakimbugwe HN, Gondwe TN, Muchadeyi FC, Nandolo W, Mulindwa HA, Banda LJ, Kaumbata W, Getachew T, Haile A, Soudre A, Ouédraogo D, Rischkowsky BA, Mwai AO, Dzomba EF, Nash O, Abegaz S, Masiga CW, Wurzinger M, Sayre BL, Stella A, Tosser-Klopp G, Sonstegard TS. The African Goat Improvement Network: a scientific group empowering smallholder farmers. Front Genet 2023; 14:1183240. [PMID: 37712066 PMCID: PMC10497955 DOI: 10.3389/fgene.2023.1183240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 07/27/2023] [Indexed: 09/16/2023] Open
Abstract
The African Goat Improvement Network (AGIN) is a collaborative group of scientists focused on genetic improvement of goats in small holder communities across the African continent. The group emerged from a series of workshops focused on enhancing goat productivity and sustainability. Discussions began in 2011 at the inaugural workshop held in Nairobi, Kenya. The goals of this diverse group were to: improve indigenous goat production in Africa; characterize existing goat populations and to facilitate germplasm preservation where appropriate; and to genomic approaches to better understand adaptation. The long-term goal was to develop cost-effective strategies to apply genomics to improve productivity of small holder farmers without sacrificing adaptation. Genome-wide information on genetic variation enabled genetic diversity studies, facilitated improved germplasm preservation decisions, and provided information necessary to initiate large scale genetic improvement programs. These improvements were partially implemented through a series of community-based breeding programs that engaged and empowered local small farmers, especially women, to promote sustainability of the production system. As with many international collaborative efforts, the AGIN work serves as a platform for human capacity development. This paper chronicles the evolution of the collaborative approach leading to the current AGIN organization and describes how it builds capacity for sustained research and development long after the initial program funds are gone. It is unique in its effectiveness for simultaneous, multi-level capacity building for researchers, students, farmers and communities, and local and regional government officials. The positive impact of AGIN capacity building has been felt by participants from developing, as well as developed country partners.
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Affiliation(s)
- Curtis P. Van Tassell
- Animal Genomics and Improvement Laboratory, USDA Agricultural Research Service, Beltsville, MD, United States
| | - Benjamin D. Rosen
- Animal Genomics and Improvement Laboratory, USDA Agricultural Research Service, Beltsville, MD, United States
| | - M. Jennifer Woodward-Greene
- Animal Genomics and Improvement Laboratory, USDA Agricultural Research Service, Beltsville, MD, United States
- National Agricultural Library, USDA Agricultural Research Service, Beltsville, MD, United States
| | - Jeffrey T. Silverstein
- Office of National Programs, USDA Agricultural Research Service, Beltsville, MD, United States
| | - Heather J. Huson
- Department of Animal Science, Cornell University, Ithaca, NY, United States
| | - Johann Sölkner
- Division of Livestock Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Paul Boettcher
- Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Rome, Italy
| | - Max F. Rothschild
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Gábor Mészáros
- Division of Livestock Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | | | - Timothy N. Gondwe
- Department of Animal Science, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Farai C. Muchadeyi
- Biotechnology Platform, Agricultural Research Council, Pretoria, South Africa
| | - Wilson Nandolo
- Department of Animal Science, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | | | - Liveness J. Banda
- Department of Animal Science, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Wilson Kaumbata
- Department of Animal Science, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Tesfaye Getachew
- International Center for Agricultural Research in the Dry Areas, Addis Ababa, Ethiopia
| | - Aynalem Haile
- International Center for Agricultural Research in the Dry Areas, Addis Ababa, Ethiopia
| | - Albert Soudre
- Unité de Formation et de Recherches - Sciences et Technologies, Université Norbert ZONGO, Koudougou, Burkina Faso
| | | | | | | | - Edgar Farai Dzomba
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa
| | - Oyekanmi Nash
- National Biotechnology Development Agency, Abuja, Nigeria
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | | | - Maria Wurzinger
- Division of Livestock Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Brian L. Sayre
- Department of Biology, Virginia State University, Petersburg, VA, United States
| | - Alessandra Stella
- Institute of Agricultural Biology and Biotechnology (IBBA), Milano, Italy
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Asmare S, Alemayehu K, Mwacharo J, Haile A, Abegaz S, Ahbara A. Genetic diversity and within-breed variation in three indigenous Ethiopian sheep based on whole-genome analysis. Heliyon 2023; 9:e14863. [PMID: 37089312 PMCID: PMC10119558 DOI: 10.1016/j.heliyon.2023.e14863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
The objective of this work was to study genetic diversity by comparing whole genome sequence data of Rutana, Gumuz and Washera sheep found in Amhara and Benishanguel gumuz regional states of Ethiopia. We employed variant calling format tools version 0.1.15 to calculate some genetic diversity indices such as observed heterozygosity, expected heterozygosity, inbreeding coefficient, and nucleotide diversity. The results revealed that, observed heterozygosity ranged from 0.33 in Gumuz to 0.34 in Rutana and Washera sheep. Expected heterozygosity ranged from 0.37 in Rutana to 0.38 in Gumuz and Washera sheep. Expected heterozygosity was found to be higher than observed heterozygosity. Higher inbreeding coefficient (0.12) was recorded for Gumuz sheep compared to 0.09 of Rutana and Washera sheep. Mean nucleotide diversity values were 0.0029, 0.0030 and 0.0028 for Gumuz, Rutana and Washera sheep, respectively. Higher values of nucleotide diversity were recorded. Population structure analysis using principal component analysis revealed no clear separation between Gumuz, Rutana and Washera sheep populations with possibility of gene flow attributed to geographical location proximity. The smaller population size, closed breeding system, genetic drift and uncontrolled (non-random) mating might lead to higher rate of inbreeding in Gumuz, Rutana and Washera sheep, requiring timely intervention. This intervention helps to prevent inbreeding depression and extinction of these valuable breeds of sheep, which helps in sustaining the livelihood of sheep keepers in lowlands and highlands. Nevertheless, the whole-genome analysis revealed high within-breed variation. Uncovered areas of studies like mapping quantitative trait loci, identifying genes underpinning productivity traits such as carcass quantity and meat quality could be carried out on diversified sheep resources identified by the current study. Identifying the genomic regions and biological pathways that contribute to explaining variability in these traits is of great importance for selection purposes. Designing conservation-based within-breed sheep selective breeding programs are recommended considering economically important traits into account.
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Affiliation(s)
- Sisay Asmare
- Debre Markos University, Burie Campus, P.O. Box 18, Ethiopia
- Bahir Dar University, College of Agriculture and Environmental Sciences, Department of Animal Production and Technology, Bahir Dar, Ethiopia
- Biotechnology Research Institute of Bahir Dar University, Ethiopia
- Corresponding author. Debre Markos University, Burie Campus, P.O. Box 18, Ethiopia.
| | - Kefyalew Alemayehu
- Bahir Dar University, College of Agriculture and Environmental Sciences, Department of Animal Production and Technology, Bahir Dar, Ethiopia
- Biotechnology Research Institute of Bahir Dar University, Ethiopia
| | - Joram Mwacharo
- Small Ruminant Genomics, International Centre for Agricultural Research in the Dry Areas (ICARDA), Addis Ababa, Ethiopia
| | - Aynalem Haile
- International Center for Agricultural Research in the Dry Areas (ICARDA), Addis Ababa, Ethiopia
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Abulgasim Ahbara
- Animal and Veterinary Sciences, SRUC, The Roslin Institute Building, Midlothian, Edinburgh, UK
- Departments of Zoology, Faculty of Sciences, Misurata University, Misurata, Libya
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Negash F, Abegaz S, Tadesse Y, Jembere T, Esatu W, Dessie T. Evaluation of growth performance and feed efficiency in reciprocal crosses of Fayoumi with three exotic chicken breeds. ACTA AGR SCAND A-AN 2023. [DOI: 10.1080/09064702.2023.2168743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Fikrineh Negash
- Adami Tulu Agricultural Research Center, Batu, Ethiopia
- School of Animal and Range Sciences, Haramaya University, Haramaya, Ethiopia
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Yosef Tadesse
- School of Animal and Range Sciences, Haramaya University, Haramaya, Ethiopia
| | - Temesgen Jembere
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Wondmeneh Esatu
- International Livestock Research Institute, Addis Ababa, Ethiopia
| | - Tadelle Dessie
- International Livestock Research Institute, Addis Ababa, Ethiopia
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Welday K, Abegaz S, Urge M, Abebe A, Mezgebe G. Defining smallholders' breeding objectives for common Tigray highland sheep in Northern Ethiopia. J Anim Breed Genet 2022; 139:623-633. [PMID: 35959565 DOI: 10.1111/jbg.12736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 07/16/2022] [Indexed: 11/30/2022]
Abstract
A sound breeding objective is a basis for genetic improvement in the overall economic merit of farm animals. This study aimed to define smallholders' sheep breeding objectives using a conjoint-based choice experiment and bio-economic model. Multinomial logistic regression analysis showed differences (p < 0.001) among the derived weights allocated by farmers to body size, twining rate, mothering ability, libido, tail type, colour and lambing interval which formed the high priority traits. The likelihood values of farmer's top three preferred traits for ram were body size (0.659 ± 0.009), tail type (0.325 ± 0.016) and libido (0.247 ± 0.016) while body size (0.459 ± 0.010), twining rate (0.313 ± 0.010) and mothering ability (0.261 ± 0.010) were more preferred traits for selection of breeding ewes. Conjoint-based choice experiment and bio-economic model indicated that live body weight at 6 months of age, twining rate (litter size) and mothering ability (preweaning lamb survival) were the most economically important traits of the breeding ewes. A genetic improvement by one genetic standard deviation (σa ) in these traits resulted in a profit of Ethiopian Birr 36.03-60.47/ewe/year. A fair correlation (r = 0.63) was observed between farmers' traits preference (conjoint-based choice card experiment) and the estimated economic value of traits indicating a good relationship between farmers' preferences for traits and economic values of the traits. This would indicate that weighting traits in selection indexes with farmers' trait selection using a conjoint-based choice experiment would direct genetic improvement towards desired profitability. Moreover, the fair correspondence between the two methods suggests that bio-economic modelling, if designed properly considering farmers' concerns, could be used to reflect farmers' breeding objectives. Therefore, for reasonable genetic progress and sheep flock profitability, more attention should be given to litter size, preweaning lamb survival and body weight at 6 months of age as they are preferred by farmers and their economic weights. Further, research on the modalities for complementary use of the two methods to define breeding objectives under smallholder conditions is warranted.
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Affiliation(s)
- Kiflay Welday
- Department of Animal and Range Sciences, Jigjiga University, Jigjiga, Ethiopia
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research (EIAR), Addis Ababa, Ethiopia
| | - Mengistu Urge
- School of Animal and Range Sciences, Haramaya University, Dire Dawa, Ethiopia
| | - Ayele Abebe
- Ethiopian Institute of Agricultural Research (EIAR), Addis Ababa, Ethiopia
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Gessesse T, Dagnew Y, Abegaz S, Tesfa A. Growth Performance and Survival Rate of Fogera and Their Crossbred Calves at Government Ranches in Ethiopia. Front Anim Sci 2021. [DOI: 10.3389/fanim.2021.745682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The economic benefit of dairy products can be enhanced by increasing the efficiency of growth and survival rate of calves. The objective of the study was to evaluate the effects of non-genetic factors on pre- and post-weaning growth traits and mortality rate of pure Fogera and their F1 cross Fogera × Holstein Friesian calves at the Andassa and Chagni Cattle Breeding and Improvement Ranch. Retrospective types of study design and direct measurement were used to collect the data. A total of 3,626 for pre-weaning weight records and 107 for post-weaning measurements were used for analysis. Genotype, sex, dam parity, year of birth, the season of birth, and location were the considered production factors. The overall least square means (LSM ± SE) of birth weights were 22.33 ± 0.12 and 24.56 ± 0.11 kg for Fogera and their crosses, respectively. The overall LSM ± SE of weaning weights were 93.25 ± 0.85 and 111.63 ± 0.84 kg for Fogera and their cross calves, respectively. The overall post-weaning weight for Fogera and their cross calves were 101.02 ± 1.62 and 111.08 ± 2.65, respectively. All variables considered in the model, except dam parity, significantly (P < 0.05) affected post-weaning weight. The overall recorded mortality rate was 3% which was nearly the optimum that many scholars agreed to successful rearing practices.
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Wolde S, Mirkena T, Melesse A, Dessie T, Abegaz S. Hatchability and growth performances of normal feathered local, Sasso-RIR and their F1-cross chickens managed under on-station condition in southern Ethiopia. Trop Anim Health Prod 2021; 53:513. [PMID: 34642833 DOI: 10.1007/s11250-021-02957-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 10/04/2021] [Indexed: 11/24/2022]
Abstract
The Normal feathered local chicken (LL), Sasso-RIR (SRSR) and their F1-cross (LSR) chickens were hatched to evaluate for egg hatchability, body weight, feed efficiency, and survival rate. After 14 days of brooding, 150 chicks of each genotype were randomly selected and further replicated into five pens in a deep litter grower house consisting of 30 chicks each in a completely randomized design, and evaluated for a period of 16 weeks. Hatchability of fertile eggs was highest for LL (80.0%), intermediate for LSR (68.6%), and lowest for SRSR (55.9%) chickens. The body weight (BW) of chicks at 2 weeks of age was 80.0, 76.3, and 61.5 g/bird for SRSR, LSR, and LL, respectively, the latter being the lowest (p < 0.05). The respective BW at 8 weeks of age was 732, 587, and 451 g while at 18 weeks it was 1877, 1379, and 1070 g/bird and different from each other (p < 0.05). During 3- to 8-week and 9- to 18-week growth periods, the LL chickens were inferior (p < 0.05) in feed intake (29.7 and 66.9 g/d/bird) whereas the SRSR chickens were superior (p < 0.05) in body weight gain (15.5 and 16.3 g/d/bird) and feed conversion ratio (2.67 and 5.35 g feed/ g gain), respectively. The mortality rate of chicken was not affected by genotypes. It can be concluded that Sasso-RIR chicken genotype had played a significant role in upgrading the growth rate and market weight of the local normal feathered chicken without adverse effect on hatchability, feed efficiency, and survival rate.
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Affiliation(s)
- Shewangizaw Wolde
- School of Animal and Range Sciences, College of Agriculture, Hawassa University, Hawassa, Ethiopia. .,Areka Agricultural Research Center, Southern Agricultural Research Institute, Areka, Ethiopia.
| | - Tadele Mirkena
- School of Animal and Range Sciences, College of Agriculture, Hawassa University, Hawassa, Ethiopia.,Food and Agricultural Organization of the United Nations, Addis Ababa, Ethiopia
| | - Aberra Melesse
- School of Animal and Range Sciences, College of Agriculture, Hawassa University, Hawassa, Ethiopia
| | - Tadelle Dessie
- International Livestock Research Institute, Addis Ababa, Ethiopia
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
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Asmare S, Alemayehu K, Abegaz S, Haile A. On-farm evaluation of growth and reproductive performances of Washera and Gumuz sheep in northwestern Ethiopia: Basics for setting up breeding objectives/goals. PLoS One 2021; 16:e0254924. [PMID: 34283870 PMCID: PMC8291677 DOI: 10.1371/journal.pone.0254924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 07/06/2021] [Indexed: 11/18/2022] Open
Abstract
Growth and reproductive performance traits are traits of economic importance for sheep selection and productivity improvement interventions. This study aimed at comparative evaluation of growth and reproductive performance traits of sheep in the highland and lowland agro-ecologies of northwestern Ethiopia. Data on growth performance traits were collected from 144 Washera (78 males and 66 females) lambs and 72 Gumuz (37 males and 35 females) lambs. Data on reproductive performance traits were collected from 260 Washera (130 rams and 130 ewes) sheep and 150 Gumuz (75 rams and 75 ewes) sheep. General linear model univariate procedure was employed to analyze the collected data. Breed, the interaction effect between breed and season of birth as well as the interaction effect between breed and type of birth all exerted very high significant effect (P<0.001) on live weight at all age groups. Breed type affected pre-weaning average daily weight gain significantly (P<0.01). Pre-weaning average daily weight gain of Washera (70 g/day) was found much better performance than 60 g/day of Gumuz. Breed type exerts significant (P<0.05) effect on age at first lambing, lambing interval, annual reproductive rate and number of lambs born per ewe life time. Average age at first lambing and lambing interval of Washera sheep were 11.69 months and 9.27 months, respectively. The corresponding values for Gumuz sheep were 12.51 months and 10.43 months, respectively. Production and reproduction performance values of traits varied across the two breeds and sexes as well. These values can be used to set up breeding objectives or goals for selective breeding of sheep giving special emphasis to growth traits believed to have medium heritability values.
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Affiliation(s)
- Sisay Asmare
- Debre Markos University, Burie Campus, Debre Markos, Ethiopia
- * E-mail:
| | - Kefyalew Alemayehu
- Department of Animal Science and Technology, College of Agriculture and Environmental Sciences, Bahir Dar University, Bahir Dar, Ethiopia
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Aynalem Haile
- International Center for Agricultural Research in the Dry Areas (ICARDA), Addis Ababa, Ethiopia
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Alemu SW, Hanotte O, Kebede FG, Esatu W, Abegaz S, Bruno JE, Abrar B, Alemayehu T, Mrode R, Dessie T. Evaluation of live-body weight and the number of eggs produced for introduced and local chickens in Ethiopia. ACTA AGR SCAND A-AN 2021. [DOI: 10.1080/09064702.2021.1891278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Setegn W. Alemu
- LiveGene International Livestock Research Institute, Addis Ababa, Ethiopia
| | - Olivier Hanotte
- LiveGene International Livestock Research Institute, Addis Ababa, Ethiopia
- Cells, Organisms and Molecular Genetics, School of Life Sciences, University Park Campus, University of Nottingham, Nottingham, UK
| | - Fasil G. Kebede
- LiveGene International Livestock Research Institute, Addis Ababa, Ethiopia
- Animal Breeding and Genomics, Wageningen University & Research, Wageningen, Netherlands
| | - Wondmeneh Esatu
- LiveGene International Livestock Research Institute, Addis Ababa, Ethiopia
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Debre-Zeit Agricultural Research Center, Addis Ababa, Ethiopia
| | - Jasmine E. Bruno
- Department of Forest and Rangeland Stewardship, Colorado State University, Fort Collins, CO, USA
| | - Biazen Abrar
- Department of Animal Sciences, Haramaya University, Haramaya, Ethiopia
| | - Tesfahun Alemayehu
- Environmental Economics and Natural Resources, wageningen university and Research, Wageningen, Netherlands
| | - Raphael Mrode
- Animal Biosciences, International Livestock Research Institute, Nairobi, Kenya
- Animal Veterinary Science, Scotland Rural College, Edinburgh, UK
| | - Tadelle Dessie
- LiveGene International Livestock Research Institute, Addis Ababa, Ethiopia
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Nigussie H, Mwacharo JM, Osama S, Agaba M, Mekasha Y, Kebede K, Abegaz S, Pal SK. Correction to: Genetic diversity and matrilineal genetic origin of fat-rumped sheep in Ethiopia. Trop Anim Health Prod 2020; 52:3933. [PMID: 33094422 DOI: 10.1007/s11250-020-02427-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The article Genetic diversity and matrilineal genetic origin of fat-rumped sheep in Ethiopia, written by Nigussie H., Mwacharo J.M., Osama S., Agaba M., Mekasha Y., Kebede K., Abegaz S., Pal S.K., was originally published Online First without Open Access.
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Affiliation(s)
- Helen Nigussie
- Department of Microbial, Cellular and Molecular Biology, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
| | - Joram M Mwacharo
- International Center for Agricultural Research in the Dry Areas (ICARDA), c/o ILRI, P.O. Box 5689, Addis Ababa, Ethiopia
| | - Sarah Osama
- Biosciences eastern and central Africa (BecA-ILRI), International Livestock Research Institute, P.O. Box 30709 00100, Nairobi, Kenya
| | - Morris Agaba
- The Nelson Mandela African Institution of Science and Technology (NM-AIST), P.O. Box 447, Arusha, Tanzania
| | - Yoseph Mekasha
- The Agricultural Transformation Agency, Addis Ababa, Ethiopia
| | - Kefelegn Kebede
- Department of Animal Breeding and Husbandry in the tropics and Sub tropics-490h, Institute of Agricultural Sciences in the Tropics, University of Hohenheim Garrbenstr, 17/, 70599, Stuttgart, Germany
| | - Solomon Abegaz
- Ethiopian Institutes of Agricultural Research, P.O. Box 32, Debre Zeit, Ethiopia
| | - Sanjoy Kumar Pal
- School of Pharmaceutical & Allied Medical Sciences, School of Natural Sciences, CT University, Ludhiana, Jagraon, Punjab, 142024, India
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Passarelli S, Ambikapathi R, Gunaratna NS, Madzorera I, Canavan CR, Noor AR, Worku A, Berhane Y, Abdelmenan S, Sibanda S, Munthali B, Madzivhandila T, Sibanda LM, Geremew K, Dessie T, Abegaz S, Assefa G, Sudfeld C, McConnell M, Davison K, Fawzi W. A Chicken Production Intervention and Additional Nutrition Behavior Change Component Increased Child Growth in Ethiopia: A Cluster-Randomized Trial. J Nutr 2020; 150:2806-2817. [PMID: 32652012 PMCID: PMC7549301 DOI: 10.1093/jn/nxaa181] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/28/2020] [Accepted: 06/05/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Chicken production in the context of nutrition-sensitive agriculture may benefit child nutrition in low-income settings. OBJECTIVES This study evaluated effects of 1) a chicken production intervention [African Chicken Genetic Gains (ACGG)], and 2) the ACGG intervention with nutrition-sensitive behavior change communication (BCC) [ACGG + Agriculture to Nutrition (ATONU)], on child nutrition and health outcomes and hypothesized intermediaries. METHODS Forty ACGG villages received 25 genetically improved chickens and basic husbandry guidance; of these, 20 ACGG + ATONU villages in addition received a nutrition-sensitive behavior change and homegardening intervention; 20 control clusters received no intervention. We assessed effects of the interventions on height-for-age z scores (HAZ), weight-for-age z scores (WAZ), and weight-for-height z scores (WHZ) at 9 (midline) and 18 mo (endline) through unadjusted and adjusted ordinary least squares (OLS) regressions. We examined the interventions' effects on hypothesized intermediaries including egg production and consumption, dietary diversity, women's empowerment, income, child morbidities, anemia, and chicken management practices through OLS and log binomial models. RESULTS Data included 829 children aged 0-36 mo at baseline. ACGG + ATONU children had higher midline HAZ [mean difference (MD): 0.28; 95% CI: 0.02, 0.54] than controls. The ACGG group had higher HAZ (MD: 0.28; 95% CI: 0.05, 0.50) and higher WAZ (MD: 0.18; 95% CI: 0.01, 0.36) at endline than controls; after adjusting for potential baseline imbalance, effects were similar but not statistically significant. At endline, differences in ACGG + ATONU children's HAZ and WAZ compared with controls were similar in magnitude to those of ACGG, but not statistically significant. There were no differences in anthropometry between the intervention groups. ACGG + ATONU children had higher dietary diversity and egg consumption than ACGG children at endline. Both interventions showed improvements in chicken management practices. The interventions did not increase anemia, diarrhea, fever, or vomiting, and the ACGG + ATONU group at midline showed reduced risk of fever. CONCLUSIONS A chicken production intervention with or without nutrition-sensitive BCC may have benefited child nutrition and did not increase morbidity.This trial was registered at clinicaltrials.gov as NCT03152227.
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Affiliation(s)
- Simone Passarelli
- Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Ramya Ambikapathi
- Department of Public Health, Purdue University, West Lafayette, IN, USA
| | | | - Isabel Madzorera
- Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Chelsey R Canavan
- Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Abdallah R Noor
- Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Amare Worku
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | - Yemane Berhane
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | | | - Simbarashe Sibanda
- Food, Agriculture and Natural Resources Policy Analysis Network, Pretoria, South Africa
| | - Bertha Munthali
- Food, Agriculture and Natural Resources Policy Analysis Network, Pretoria, South Africa
| | | | - Lindiwe M Sibanda
- Food, Agriculture and Natural Resources Policy Analysis Network, Pretoria, South Africa
| | | | - Tadelle Dessie
- International Livestock Research Institute, Addis Ababa, Ethiopia
| | - Solomon Abegaz
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Getnet Assefa
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Christopher Sudfeld
- Department of Global Health and Population, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Margaret McConnell
- Department of Global Health and Population, Harvard TH Chan School of Public Health, Boston, MA, USA
| | | | - Wafaie Fawzi
- Department of Global Health and Population, Harvard TH Chan School of Public Health, Boston, MA, USA
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Nigussie H, Mwacharo JM, Osama S, Agaba M, Mekasha Y, Kebede K, Abegaz S, Pal SK. Genetic diversity and matrilineal genetic origin of fat-rumped sheep in Ethiopia. Trop Anim Health Prod 2019; 51:1393-1404. [PMID: 30798433 PMCID: PMC7826308 DOI: 10.1007/s11250-019-01827-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 01/21/2019] [Indexed: 11/23/2022]
Abstract
Ethiopia is home to a diverse gene pool of indigenous sheep populations. Therefore, a better understanding of genetic variation holds the key to future utilization through conservation. Three of these breeds, Afar, Blackhead Somali, and Hararghe Highland, are found in eastern Ethiopia where they contribute significantly to the livelihood of most pastoralist, agro-pastoralist, and smallholder farmers. These indigenous sheep are recognized on the basis of morphotype and their genetic distinction remains unknown. Here, to assess genetic variation, and matrilineal genetic origin and relationship of fat-rumed sheep found in eastern Ethiopia, 300 individuals from the three breeds were genotyped for 22 microsatellite markers and sequenced for the mitochondrial DNA displacement loop (mtDNA d-loop) region. The overall HO and HE were 0.57 and 0.75, respectively. Differentiation statistics revealed that a high proportion (97%) of the total genetic variation was explained by differences between individuals within populations. Genotype assignment independent of the population of origin showed K = 2 to be the optimum number of genetic backgrounds present in the dataset. This result was further confirmed by mtDNA D-loop sequences comparison in which the matrilineal genetic origin of eastern Ethiopia sheep is from two haplotype groups (types A and B) among the five haplotypes globally observed. Taken together, our findings suggest that the sheep populations from three breeds originated from two ancestral genetic backgrounds that may have diverged prior to their introduction to Ethiopia. However, to obtain a complete picture of the evolutionary dynamics of Ethiopian indigenous sheep, more samples and populations from within and outside of the country will need to be analyzed.
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Affiliation(s)
- Helen Nigussie
- Department of Microbial, Cellular and Molecular Biology, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
| | - Joram M Mwacharo
- International Center for Agricultural Research in the Dry Areas (ICARDA) c/o ILRI, P.O. Box 5689, Addis Ababa, Ethiopia
| | - Sarah Osama
- Biosciences eastern and central Africa (BecA-ILRI), International Livestock Research Institute, P.O. Box 30709 00100, Nairobi, Kenya
| | - Morris Agaba
- The Nelson Mandela African Institution of Science and Technology (NM-AIST), P.O. Box 447, Arusha, Tanzania
| | - Yoseph Mekasha
- The Agricultural Transformation Agency, Addis Ababa, Ethiopia
| | - Kefelegn Kebede
- Institute of Agricultural Sciences in the Tropics, Department of Animal Breeding and Husbandry in the tropics and Sub tropics- 490h, University of Hohenheim Garrbenstr, 17/70599, Stuttgart, Germany
| | - Solomon Abegaz
- Ethiopian Institutes of Agricultural Research, P.O. Box 32, Debre Zeit, Ethiopia
| | - Sanjoy Kumar Pal
- School of Pharmaceutical & Allied Medical Sciences, School of Natural Sciences, CT University, Jagraon Ludhiana, Punjab, 142024, India
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Nigussie H, Agaba M, Mekasha Y, Abegaz S. P4058 Fecundity genes polymorphism in indigenous sheep of eastern Ethiopia. J Anim Sci 2016. [DOI: 10.2527/jas2016.94supplement4107a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abegaz S, Van Wyk JB, Olivier JJ. Estimation of genetic and phenotypic parameters of growth curve and their relationship with early growth and productivity in Horro sheep. Arch Anim Breed 2010. [DOI: 10.5194/aab-53-85-2010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract. Weight (kg)-age (days) data of 524 Horro sheep of Ethiopia were fitted to a Brody function to estimate parameters of growth curve and their genetic and phenotypic parameters. Genetic and phenotypic relationships were also estimated between growth curve parameters and weight at birth (BW), weaning (WW) six-month (WT6) and yearling (YW). For ewes Pearson correlations were also calculated between growth curve parameters and ewe productivity over first to fourth parities. Least squares means of growth curve parameters A (asymptotic mature weight, kg), B (proportion of mature weight attained after birth) and K (the rate of maturity, kg gain kg-1 body weight) were 37.6, 0.88, and 0.27∙10-2, respectively. Heritability estimates were 0.29, 0.18 and 0.14 for A, B, and K, respectively. Genetic correlations between A and B, A and K, and B and K were 0.39, −0.07, and 0.25 respectively. Genetic correlations of A and K with BW, WW, WT6, and YW were 0.27 and −0.13, 0.34 and 0.37, 0.44 and 0.61, and 0.67 and 0.66, respectively. The growth curve parameters have small but positive (r=0.05 to 0.28) relationship with indicators of lifetime productivity. Medium heritability estimates of A and K indicate that progress in improving these traits can be made through selection. WT6 and YW have medium genetic correlations with the growth curve parameters and these may allow the use of these weights as indirect early selection criteria for optimum growth curve.
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Abegaz S, van Wyk JB, Olivier JJ. Estimates of (co)variance function for growth to yearling in Horro sheep of Ethiopia using random regression model. Arch Anim Breed 2010. [DOI: 10.5194/aab-53-689-2010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract. Random regression analyses of weight data from birth to 396 days were done using 22 141 weight records of 1 951 Horro lambs. Six different models formed from three different orthogonal polynomial regressions (legendre scale)orders (quadratic, cubic, quartic) of fit for both additive genetic and animals’ permanent environmental effects, with assumption of either homogeneous or heterogeneous residual variance, were compared. Fixed effects of year and type of birth, sex and age of dam were fitted along with a fourth order polynomial. Both likelihood ratio test (LRT) and Akaike's Information Criterion (AIC) were used for model comparison. Model fit improved with increased order of polynomial and assumption of heterogeneity of residual variance. Components for additive genetic and permanent environmental (co)variance increased from 0.03 and 0.09 at birth to 23.8 and 37.6 at 396 days of age, respectively. The first three eigenvalues of the coefficient matrix of the additive genetic covariance accounted for about 98 % of the sum of all the eigenvalues. Heritability estimates have shown a declining and increasing trend at different parts of the trajectory, the lowest estimate being 0.14 for weight at birth while the highest being 0.36 for weight at about 390 days of age. Higher heritability estimates in previous uni- and bi-variate models and in the current study and also strong correlation with weight at early age makes weight at one year of age the most important trait to consider in improving productivity in Horro sheep.
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Abegaz S, Van Wyk JB, Olivier JJ. Model comparisons and genetic and environmental parameter estimates of growth and the Kleiber ratio in Horro sheep. S AFR J ANIM SCI 2007. [DOI: 10.4314/sajas.v35i1.4046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abegaz S, Gemeda D, Rege J, Van Wyk J, Neser F, Erasmus G. Early growth, survival and litter size in Ethiopian Horro sheep. S AFR J ANIM SCI 2000. [DOI: 10.4314/sajas.v30i4.3884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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