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Rambaldi Migliore N, Bigi D, Milanesi M, Zambonelli P, Negrini R, Morabito S, Verini-Supplizi A, Liotta L, Chegdani F, Agha S, Salim B, Beja-Pereira A, Torroni A, Ajmone‐Marsan P, Achilli A, Colli L. Mitochondrial DNA control-region and coding-region data highlight geographically structured diversity and post-domestication population dynamics in worldwide donkeys. PLoS One 2024; 19:e0307511. [PMID: 39197009 PMCID: PMC11356394 DOI: 10.1371/journal.pone.0307511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 07/05/2024] [Indexed: 08/30/2024] Open
Abstract
Donkeys (Equus asinus) have been used extensively in agriculture and transportations since their domestication, ca. 5000-7000 years ago, but the increased mechanization of the last century has largely spoiled their role as burden animals, particularly in developed countries. Consequently, donkey breeds and population sizes have been declining for decades, and the diversity contributed by autochthonous gene pools has been eroded. Here, we examined coding-region data extracted from 164 complete mitogenomes and 1392 donkey mitochondrial DNA (mtDNA) control-region sequences to (i) assess worldwide diversity, (ii) evaluate geographical patterns of variation, and (iii) provide a new nomenclature of mtDNA haplogroups. The topology of the Maximum Parsimony tree confirmed the two previously identified major clades, i.e. Clades 1 and 2, but also highlighted the occurrence of a deep-diverging lineage within Clade 2 that left a marginal trace in modern donkeys. Thanks to the identification of stable and highly diagnostic coding-region mutational motifs, the two lineages were renamed as haplogroup A and haplogroup B, respectively, to harmonize clade nomenclature with the standard currently adopted for other livestock species. Control-region diversity and population expansion metrics varied considerably between geographical areas but confirmed North-eastern Africa as the likely domestication center. The patterns of geographical distribution of variation analyzed through phylogenetic networks and AMOVA confirmed the co-occurrence of both haplogroups in all sampled populations, while differences at the regional level point to the joint effects of demography, past human migrations and trade following the spread of donkeys out of the domestication center. Despite the strong decline that donkey populations have undergone for decades in many areas of the world, the sizeable mtDNA variability we scored, and the possible identification of a new early radiating lineage further stress the need for an extensive and large-scale characterization of donkey nuclear genome diversity to identify hotspots of variation and aid the conservation of local breeds worldwide.
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Affiliation(s)
- Nicola Rambaldi Migliore
- Dipartimento di Biologia e Biotecnologie “Lazzaro Spallanzani”, University of Pavia, Via A. Ferrata, Pavia, Italy
| | - Daniele Bigi
- Dipartimento di Scienze e Tecnologie Agro-Alimentari (DISTAL), Alma Mater Studiorum Università di Bologna, Viale Giuseppe Fanin, Bologna, Italy
| | - Marco Milanesi
- Dipartimento di Scienze Animali, della Nutrizione e degli Alimenti, Università Cattolica del S. Cuore, via Emilia Parmense, Piacenza, Italy
| | - Paolo Zambonelli
- Dipartimento di Scienze e Tecnologie Agro-Alimentari (DISTAL), Alma Mater Studiorum Università di Bologna, Viale Giuseppe Fanin, Bologna, Italy
| | - Riccardo Negrini
- Dipartimento di Scienze Animali, della Nutrizione e degli Alimenti, Università Cattolica del S. Cuore, via Emilia Parmense, Piacenza, Italy
| | - Simone Morabito
- Dipartimento di Scienze Animali, della Nutrizione e degli Alimenti, Università Cattolica del S. Cuore, via Emilia Parmense, Piacenza, Italy
| | | | - Luigi Liotta
- Department of Veterinary Sciences, University of Messina, V.le Palatucci, Messina, Italy
| | - Fatima Chegdani
- Dipartimento di Scienze Animali, della Nutrizione e degli Alimenti, Università Cattolica del S. Cuore, via Emilia Parmense, Piacenza, Italy
| | - Saif Agha
- Animal Production Department, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
| | - Bashir Salim
- Department of Parasitology, Faculty of Veterinary Medicine, University of Khartoum, Khartoum-North, Sudan
- Camel Research Center, King Faisal University, Al-Ahsa, Saudi Arabia
| | - Albano Beja-Pereira
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, Vairão, Portugal
- BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, Vairão, Portugal
- DGAOT, Faculty of Sciences, Universidade do Porto, Rua Campo Alegre, Porto, Portugal
| | - Antonio Torroni
- Dipartimento di Biologia e Biotecnologie “Lazzaro Spallanzani”, University of Pavia, Via A. Ferrata, Pavia, Italy
| | - Paolo Ajmone‐Marsan
- Dipartimento di Scienze Animali, della Nutrizione e degli Alimenti, Università Cattolica del S. Cuore, via Emilia Parmense, Piacenza, Italy
- CREI Romeo and Enrica Invernizzi Research Center on Sustainable Dairy Production, Università Cattolica del S. Cuore, Piacenza (PC), Italy
| | - Alessandro Achilli
- Dipartimento di Biologia e Biotecnologie “Lazzaro Spallanzani”, University of Pavia, Via A. Ferrata, Pavia, Italy
| | - Licia Colli
- Dipartimento di Scienze Animali, della Nutrizione e degli Alimenti, Università Cattolica del S. Cuore, via Emilia Parmense, Piacenza, Italy
- BioDNA Centro di Ricerca Sulla Biodiversità e sul DNA Antico, Università Cattolica del S. Cuore, Piacenza (PC), Italy
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Susana Lopes M, Azevedo AR, Mendonça D, Rojer H, Cabral V, Ceraolo F, Canto Brum C, Mendes B, da Câmara Machado A. Morphological and genetic characterization of the Graciosa donkey breed. JOURNAL OF APPLIED ANIMAL RESEARCH 2023. [DOI: 10.1080/09712119.2023.2171421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Affiliation(s)
- Maria Susana Lopes
- Centro de Biotecnologia dos Açores, Universidade dos Açores, Angra do Heroísmo, Açores, Portugal
| | - Ana Rita Azevedo
- Centro de Biotecnologia dos Açores, Universidade dos Açores, Angra do Heroísmo, Açores, Portugal
| | - Duarte Mendonça
- Centro de Biotecnologia dos Açores, Universidade dos Açores, Angra do Heroísmo, Açores, Portugal
| | - Horst Rojer
- Centro de Biotecnologia dos Açores, Universidade dos Açores, Angra do Heroísmo, Açores, Portugal
| | - Verónica Cabral
- Centro de Biotecnologia dos Açores, Universidade dos Açores, Angra do Heroísmo, Açores, Portugal
| | - Franco Ceraolo
- Associação de Criadores e Amigos do Burro Anão da Ilha Graciosa, Açores, Portugal
| | - Carlos Canto Brum
- Associação de Criadores e Amigos do Burro Anão da Ilha Graciosa, Açores, Portugal
| | - Bruno Mendes
- CRL, Unicol-Cooperativa Agrícola, Açores, Portugal
| | - Artur da Câmara Machado
- Centro de Biotecnologia dos Açores, Universidade dos Açores, Angra do Heroísmo, Açores, Portugal
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Huang B, Khan MZ, Chai W, Ullah Q, Wang C. Exploring Genetic Markers: Mitochondrial DNA and Genomic Screening for Biodiversity and Production Traits in Donkeys. Animals (Basel) 2023; 13:2725. [PMID: 37684989 PMCID: PMC10486882 DOI: 10.3390/ani13172725] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 08/15/2023] [Accepted: 08/23/2023] [Indexed: 09/10/2023] Open
Abstract
Donkeys (Equus asinus) play a pivotal role as essential livestock in arid and semi-arid regions, serving various purposes such as transportation, agriculture, and milk production. Despite their significance, donkey breeding has often been overlooked in comparison to other livestock species, resulting in limited genetic improvement programs. Preserving donkey genetic resources within each country necessitates the establishment of breed conservation programs, focusing on managing genetic diversity among populations. In recent years, significant strides have been made in sequencing and analyzing complete mitochondrial DNA (mtDNA) molecules in donkeys. Notably, numerous studies have honed in on the mitochondrial D-loop region, renowned for its remarkable variability and higher substitution rate within the mtDNA genome, rendering it an effective genetic marker for assessing genetic diversity in donkeys. Furthermore, genetic markers at the RNA/DNA level have emerged as indispensable tools for enhancing production and reproduction traits in donkeys. Traditional animal breeding approaches based solely on phenotypic traits, such as milk yields, weight, and height, are influenced by both genetic and environmental factors. To overcome these challenges, genetic markers, such as polymorphisms, InDel, or entire gene sequences associated with desirable traits in animals, have achieved widespread usage in animal breeding practices. These markers have proven increasingly valuable for facilitating the selection of productive and reproductive traits in donkeys. This comprehensive review examines the cutting-edge research on mitochondrial DNA as a tool for assessing donkey biodiversity. Additionally, it highlights the role of genetic markers at the DNA/RNA level, enabling the informed selection of optimal production and reproductive traits in donkeys, thereby driving advancements in donkey genetic conservation and breeding programs.
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Affiliation(s)
- Bingjian Huang
- Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Agricultural Science and Engineering School, Liaocheng University, Liaocheng 252000, China
- College of Life Sciences, Liaocheng University, Liaocheng 252059, China
| | - Muhammad Zahoor Khan
- Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Agricultural Science and Engineering School, Liaocheng University, Liaocheng 252000, China
- Faculty of Veterinary and Animal Sciences, University of Agriculture, Dera Ismail Khan 29220, Pakistan
| | - Wenqiong Chai
- Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Agricultural Science and Engineering School, Liaocheng University, Liaocheng 252000, China
| | - Qudrat Ullah
- Faculty of Veterinary and Animal Sciences, University of Agriculture, Dera Ismail Khan 29220, Pakistan
| | - Changfa Wang
- Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Agricultural Science and Engineering School, Liaocheng University, Liaocheng 252000, China
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Wang Y, Hua X, Shi X, Wang C. Origin, Evolution, and Research Development of Donkeys. Genes (Basel) 2022; 13:1945. [PMID: 36360182 PMCID: PMC9689456 DOI: 10.3390/genes13111945] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/24/2022] [Accepted: 10/24/2022] [Indexed: 08/11/2023] Open
Abstract
Lack of archaeological and whole-genome diversity data has restricted current knowledge of the evolutionary history of donkeys. With the advancement of science and technology, the discovery of archaeological evidence, the development of molecular genetics, and the improvement of whole-genome sequencing technology, the in-depth understanding of the origin and domestication of donkeys has been enhanced, however. Given the lack of systematic research, the present study carefully screened and collected multiple academic papers and books, journals, and literature on donkeys over the past 15 years. The origin and domestication of donkeys are reviewed in this paper from the aspects of basic information, cultural origin, bioarcheology, mitochondrial and chromosomal microsatellite sequences, and whole-genome sequence comparison. It also highlights and reviews genome assembly technology, by assembling the genome of an individual organism and comparing it with related sample genomes, which can be used to produce more accurate results through big data statistics, analysis, and computational correlation models. Background: The donkey industry in the world and especially in China is developing rapidly, and donkey farming is transforming gradually from the family farming model to large-scale, intensive, and integrated industrial operations, which could ensure the stability of product quality and quantity. However, theoretical research on donkey breeding and its technical development lags far behind that of other livestock, thereby limiting its industrial development. This review provides holistic information for the donkey industry and researchers, that could promote theoretical research, genomic selection (GS), and reproductive management of the donkey population.
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Maternal Phylogenetic Relationships and Genetic Variation among Rare, Phenotypically Similar Donkey Breeds. Genes (Basel) 2021; 12:genes12081109. [PMID: 34440283 PMCID: PMC8392470 DOI: 10.3390/genes12081109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/02/2021] [Accepted: 07/13/2021] [Indexed: 11/17/2022] Open
Abstract
The mitochondrial DNA (mtDNA) D-loop of endangered and critically endangered breeds has been studied to identify maternal lineages, characterize genetic inheritance, reconstruct phylogenetic relations among breeds, and develop biodiversity conservation and breeding programs. The aim of the study was to determine the variability remaining and the phylogenetic relationship of Martina Franca (MF, with total population of 160 females and 36 males), Ragusano (RG, 344 females and 30 males), Pantesco (PT, 47 females and 15 males), and Catalonian (CT) donkeys by collecting genetic data from maternal lineages. Genetic material was collected from saliva, and a 350 bp fragment of D-loop mtDNA was amplified and sequenced. Sequences were aligned and evaluated using standard bioinformatics software. A total of 56 haplotypes including 33 polymorphic sites were found in 77 samples (27 MF, 22 RG, 8 PT, 19 CT, 1 crossbred). The breed nucleotide diversity value (π) for all the breeds was 0.128 (MF: 0.162, RG: 0.132, PT: 0.025, CT: 0.038). Principal components analysis grouped most of the haplogroups into two different clusters, I (including all haplotypes from PT and CT, together with haplotypes from MF and RG) and II (including haplotypes from MF and RG only). In conclusion, we found that the primeval haplotypes, haplogroup variability, and a large number of maternal lineages were preserved in MF and RG; thus, these breeds play putative pivotal roles in the phyletic relationships of donkey breeds. Maternal inheritance is indispensable genetic information required to evaluate inheritance, variability, and breeding programs.
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Phylogenetic Relationships of Turkish Indigenous Donkey Populations Determined by Mitochondrial DNA D-loop Region. Animals (Basel) 2020; 10:ani10111970. [PMID: 33120938 PMCID: PMC7692571 DOI: 10.3390/ani10111970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 10/18/2020] [Accepted: 10/22/2020] [Indexed: 11/17/2022] Open
Abstract
Simple Summary This paper represents the first fundamental report of mtDNA diversity in Turkish indigenous donkey breeds and presents findings for the origin and genetic characterization of donkey populations dispersed in seven geographical regions in Turkey, and thus reveals insights into their genetic history. The median-joining network and phylogenetic tree exhibit two different maternal lineages of the 16 Turkish indigenous donkey populations. Abstract In this study, to analyze the mtDNA D-loop region and the origin of the maternal lineages of 16 different donkey populations, and to assess the domestication of Turkish indigenous donkeys in seven geographical regions, we investigated the DNA sequences of the D-loop region of 315 indigenous donkeys from Turkey. A total of 54 haplotypes, resulting from 35 polymorphic regions (27 parsimoniously informative and 6 singleton sites), were defined. Twenty-eight of these haplotypes are unique (51.85%), and 26 are shared among different Turkish indigenous donkey populations. The most frequent haplotype was Hap 1 (45.71%), followed by two haplotypes (Hap 4, 15.55% and Hap 7, 5.39%). The breed genetic diversity, evaluated by the haplotype diversity (HD) and nucleotide diversity (πD), for the Turkish donkey populations ranged from 0.533 ± 0.180 (Tekirdağ–Malkara, MAL) to 0.933 ± 0.122 (Aydin, AYD), and from 0.01196 ± 0.0026 (Antalya, ANT) to 0.02101 ± 0.0041 (Aydin, AYD), respectively. We observed moderate-to-high levels of haplotype diversity and moderate nucleotide diversity, indicating plentiful genetic diversity in all of the Turkish indigenous donkey populations. Phylogenetic analysis (NJT) and median-joining network analysis established that all haplotypes were distinctly grouped into two major haplogroups. The results of AMOVA analyses, based on geographic structuring of Turkish native donkey populations, highlighted that the majority of the observed variance is due to differences among samples within populations. The observed differences between groups were found to be statistically significant. Comparison among Turkish indigenous donkey mtDNA D-loop regions and haplotypes, and different countries’ donkey breeds and wild asses, identified two clades and which is named Somali (Clade IV) and Nubian (Clade V) lineages. The results can be used to understand the origin of Turkish donkey populations clearly, and to resolve the phylogenetic relationship among all of the different regions.
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Santos Alves J, da Silva Anjos M, Silva Bastos M, Sarmento Martins de Oliveira L, Pereira Pinto Oliveira I, Batista Pinto LF, Albano de Araújo de Oliveira C, Bermal Costa R, Miguel Ferreira de Camargo G. Variability analyses of the maternal lineage of horses and donkeys. Gene 2020; 769:145231. [PMID: 33065240 DOI: 10.1016/j.gene.2020.145231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/24/2020] [Accepted: 10/08/2020] [Indexed: 11/17/2022]
Abstract
Equid breeds originating from the Iberian Peninsula and North Africa are believed to have genetically contributed to the formation of breeds and ecotypes from Brazil. The country has numerous breeds and ecotypes of horses and donkeys but there are no extensive studies on maternal genetic diversity and their origins. This study reports the results of the first genetic analysis of all horse and donkey breeds/ecotypes from Brazil based on sequences of the mitochondrial DNA control region (D-loop) whose main objective was to characterize the genetic variation in these animals. These analyses will contribute to the understanding of the current population structure and diversity of breeds/ecotypes of horses and donkeys raised in the Brazil. We analyzed 310 D-loop sequences representing 41 breeds/ecotypes of Equus caballus and Equus asinus, including 14 native horse breeds/ecotypes, 3 native donkey breeds/ecotypes and 24 cosmopolite horse breeds. The results revealed that the breeds are well structured genetically and that they comprise different groups. A total of 80 and 14 haplotypes were identified for horses and donkeys, respectively. Most of the horse mtDNA haplotypes were shared by many breeds, whereas donkey mtDNA haplotypes seemed to be more group-especif. Some groups presented a low intrabreed distance and/or a low haplotype/nucleotide diversity such as Lavradeiro, Crioulo, Piquira and Percheron horses and Brazilian donkey. Thus, specific actions must be designed for each population. The different levels of genetic diversity provided important information for conservation resource management of adapted groups as well as for mating orientation of breed associations. Some autochthonous ecotypes require attention because of their low genetic variability.
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Affiliation(s)
- Jackeline Santos Alves
- Escola de Medicina Veterinária e Zootecnia, Universidade Federal da Bahia, (UFBA), Salvador, BA, Brazil
| | - Marcia da Silva Anjos
- Programa de Pós-Graduação em Biodiversidade e Evolução da UFBA, Salvador, BA, Brazil
| | - Marisa Silva Bastos
- Escola de Medicina Veterinária e Zootecnia, Universidade Federal da Bahia, (UFBA), Salvador, BA, Brazil
| | | | | | | | | | - Raphael Bermal Costa
- Escola de Medicina Veterinária e Zootecnia, Universidade Federal da Bahia, (UFBA), Salvador, BA, Brazil
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Stanisic L, Aleksić JM, Dimitrijevic V, Kovačević B, Stevanovic J, Stanimirovic Z. Banat donkey, a neglected donkey breed from the central Balkans (Serbia). PeerJ 2020; 8:e8598. [PMID: 32175186 PMCID: PMC7059758 DOI: 10.7717/peerj.8598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/19/2020] [Indexed: 11/20/2022] Open
Abstract
The dominant donkey breed in the Balkans is the mid-sized Balkan donkey with a grey to chocolate coat color. Local breeders from Serbia, however, still maintain a few larger individuals of a lighter coat color, named Banat donkey, and speculate that they are descendants of a Spanish donkey heard that had been transferred to the Banat region by the Hapsburg Queen Maria Theresa in the XVIII century for a specific purpose, to work in local vineyards. We have previously found a unique nuclear gene-pool and a prevalence of mitochondrial Clade 2 haplotypes in several such animals. In this study, we: (i) perform a comparative analysis of 18 morphological traits of the Banat donkey (seven individuals), Balkan donkey (53 individuals from two sub-populations of this breed) and the potential hybrids (eight individuals), and demonstrate the morphological distinctiveness of the Banat donkey, highlighting the diagnostic traits for distinguishing the breed: hip height, croup width, body length and chest depth; (ii) re-analyse published nuclear microsatellite data for these groups, and reveal that, although severely depopulated, the genetically distinct Banat donkey is not severely affected by the loss of genetic diversity and inbreeding; (iii) demonstrate that previously published Banat donkey mitochondrial haplotypes, analyzed genealogically together with those reported in ancient and modern individuals from Spain, Italy, Turkey, Cyprus and Africa, are shared with three Spanish breeds and individuals belonging to Amiata and some other Italian breeds. A unique morphological feature present in Banat and Somali wild donkeys, but also in Amiata donkeys, black stripes on legs, suggests that the origin of Clade 2 donkeys may be much more complex than previously thought. Actions to preserve the Banat donkey, a valuable but critically endangered genetic resource (<100 individuals), are urgent.
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Affiliation(s)
- Ljubodrag Stanisic
- Department of Reproduction, Fertility and Artificial Insemination, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
| | - Jelena M. Aleksić
- Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade, Belgrade, Serbia
| | - Vladimir Dimitrijevic
- Department of Animal Breeding and Genetics, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
| | - Branislav Kovačević
- Institute of Lowland Forestry and Environment (ILFE), University of Novi Sad, Novi Sad, Serbia
| | - Jevrosima Stevanovic
- Department of Biology, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
| | - Zoran Stanimirovic
- Department of Biology, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
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Brosnahan MM. Genetics, Evolution, and Physiology of Donkeys and Mules. Vet Clin North Am Equine Pract 2019; 35:457-467. [PMID: 31672199 DOI: 10.1016/j.cveq.2019.08.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The genus Equus is made up of donkeys, horses, and zebras. Despite significant variation in chromosome number across these species, interspecies breeding results in healthy, although infertile, hybrid offspring. Most notable among these are the horse-donkey hybrids, the mule and hinny. Donkeys presently are used for everything from companion animals to beasts of burden. Although closely related from an evolutionary standpoint, differences in anatomy and physiology preclude the assumption that they can be treated identically to the domestic horse. Veterinarians should be aware of these differences and adjust their practice accordingly.
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Affiliation(s)
- Margaret M Brosnahan
- College of Veterinary Medicine, Midwestern University, 19555 North 59th Avenue, Cactus Wren Hall 336-P, Glendale, AZ 85308, USA.
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