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• Mitochondrial DNA based genetic diversity was explored in the Indian dromedary and Bactrian camel populations. • The haplotype and nucleotide diversity in the Indian dromedaries was higher than the indices reported worldwide. • There was lack of genetic structuring in the Indian dromedaries based on geographical distribution. • Signals of population expansion were evident in the dromedary camels of India. • C. ferus , C. bactrianus and C. dromedarius revealed existence of separate mitochondrial lineages. Camels represent an important genetic resource of the desert ecosystems of India, with the dromedary and Bactrian camels inhabiting the hot and cold deserts, respectively. This study is the first attempt to investigate mitochondrial DNA based genetic diversity in the Indian camel populations and explores their relationship in the context of global genetic diversity of all the three large camel species (Camelus ferus, Camelus bactrianus and Camelus dromedaries). A mitochondrial DNA fragment encompassing part of cytochrome b gene, tRNAThr, tRNAPro and the beginning of the control region was amplified and analyzed in 72 dromedary and 8 Bactrian camels of India. Sequence analysis revealed that the haplotype and nucleotide diversity (Hd: 0.937 and π: 0.00431) in the Indian dromedaries was higher than the indices reported so far for the dromedary or Bactrian camels across the globe. The corresponding values in the Indian Bactrian camels were 1.000 and 0.00393, respectively. Signals of population expansion were evident in the dromedaries of India on the basis of mismatch analysis and Fu's Fs values. The analysis of molecular variance attributed most of the genetic variance (92.15%) between the dromedary, wild Bactrian and domestic Bactrian camels indicating separate maternal origins. The existence of three mitochondrial lineages in the old world camels (C. bactrianus : Lineage A; C. ferus : Lineage B and C. dromedarius : Lineage C) was also substantiated by the topology of the Median-Joining network. [ABSTRACT FROM AUTHOR]

• Maternal genetic diversity was explored in Indian donkeys based on whole mitogenome and D-loop sequences. • The haplotype and nucleotide diversity in Indian donkeys were 0.989 and 0.00395, respectively. • Phylogenetic analysis revealed conformity of Indian donkeys to Nubian and Somali clades of African wild ass. • Indian donkeys shared haplotypes with donkeys from different countries. To contribute to the knowledge of maternal genetic diversity in domestic donkeys, this study investigated the mitochondrial DNA variations and analyzed the genetic structure in Indian donkeys based on 31 mitogenome sequences representing four breeds/populations (Agra, Halari, Kachchhi and Spiti). A total of 27 haplotypes with a haplotype diversity value of 0.989 were evident in the donkey genetic resources of India. The genetic differentiation between the investigated populations was evaluated using population pairwise F ST values, which showed maximum differentiation between Kachchhi and Halari donkeys. The Neighbor-Joining (NJ) tree based on the whole mitogenome sequence and the Median-Joining (MJ) network for partial D-loop fragment showed clear demarcation of Indian donkeys into Nubian and Somali clades, substantiating African maternal origin of Indian domestic donkeys. The topology of the MJ network excluded the Asian wild asses as the possible progenitors of Indian donkeys. Halari and Agra donkeys showed conformity exclusively to the Nubian lineage of the African wild asses. However, representation of both the Nubian and Somali lineages was observed in Kachchhi and Spiti donkeys. Comprehensive analysis carried out by retrieving D-loop sequences from different countries representing Asia, Africa, Europe and South America revealed existence of shared haplotypes across geographically isolated regions of the globe. This observation is indicative of utility of donkeys as pack animals across inter-continental trading routes during development of human civilizations. Our results represent a valuable contribution to maternal genetic diversity of Indian donkeys and provide insights into the worldwide spread of the species following initial domestication in Africa. [ABSTRACT FROM AUTHOR]

• Genetic diversity was explored in 33 breeds/populations of Indian goats using mitochondrial DNA markers. • The haplotype and nucleotide diversity indices of Indian goats were 0.998 and 0.028, respectively. • Indian goats belong to four maternal haplogroups; A, B, C and D. • There was no genetic structuring of goats on the basis of geographical distribution. Thirty four distinct breeds and many non-descript populations represent the caprine diversity of India. Genetic characterization of breeds is an essential element in designing breeding strategies and preserving genetic diversity. Considering the popularity of mitochondrial DNA for phylogeographical studies, this study involved an extensive analysis of population structure and genetic diversity of 28 defined breeds and 5 lesser known populations representing all four major agro-climatic zones of India using mitochondrial DNA markers. Analysis of hypervariable region 1 of mtDNA control region in 443 goats together with 22 reference sequences, delineated 341 distinct haplotypes belonging to four maternal haplogroups; A, B, C and D, with haplogroup A representing 90% of the individuals. The haplotype and nucleotide diversity indices of Indian goats were 0.998 ± 0.001 and 0.028 ± 0.001, respectively indicating abundant genetic variability. Estimates of population demographic parameters from mismatch analysis suggested a relatively good fit to the model of either spatial or demographic expansion of Indian goats. AMOVA analysis and topology of MJ network suggested lack of phylogeographic structure in domestic goats, which can be attributed to unstructured animal breeding, dwindling pastures and nomadic pastoralism. Genetic differentiation between goats from different agro-ecological regions was in accordance with their geographical propinquity. [ABSTRACT FROM AUTHOR]