Freezability and Fertility Rates of Stallion Semen Supplemented With Trehalose in Lactose Extender.

Cryopreservation of stallion semen is often associated with poor post-thaw sperm quality. One of the reason for this diminished quality is osmotic stress that spermatozoa experiences during freezing and thawing process. The aim of the present study was to evaluate the cryoprotective effect of trehalose on stallion sperm quality and field fertility rates subjected to cooling and freeze-thawing process. Semen samples were collected from six Marwari breed stallions, divided into three different treatments in a final concentration of 150 × 106 sperm/mL by using Lactose based extender containing 0, 50, and 150 mM of trehalose then subjected to cryopreservation after equilibration. Sperm motility, acrosome integrity, plasma membrane integrity, mitochondrial membrane potential, DNA integrity and oxidative stress related parameters of the stallion spermatozoa were analyzed at fresh, prefreeze and post thaw stages. Thirty (30) reproductively healthy mares were inseminated with frozen-thawed semen either supplemented with (treatment) or without (control) trehalose to evaluate the field fertility. Results of the current study indicated that, the extender containing 50 mM trehalose has enhanced the functional plasma membrane, acrosomal, DNA integrities and augmented the mitochondrial membrane potential. Trehalose supplementation to the semen extender not only ameliorated the semen quality parameters, but also protected the stallion sperm from oxidative stress by reducing the levels of reactive oxygen species (ROS) and lipid peroxidation (LPO). The inclusion of 50 mM trehalose in semen extender resulted in significantly (P < .05) increased post-thaw progressive motility and viability compared to the control group. Mares inseminated with frozen-thawed semen supplemented with 50 mM trehalose tended to have better pregnancy rates than controls (non-significant [P < .05]) although a larger fertility trial is required to determine if this effect reaches the level of significance. In conclusion, addition of 50 mM trehalose yielded in better quality stallion semen after cooling and post-thawing in terms of reducing the oxidative stress and enhancing the motility, integrities of acrosome, plasma membrane, mitochondrial potential and DNA.

Single Nucleotide Polymorphism in Interleukin-6 and Interleukin-8 Genes of Equines.

In equines, muscle exercise highly affects the expression of genes which are associated with secretion of cytokines. Myokines are the group of cytokines that are produced by skeletal muscles during exercise. Interleukin-6 (IL-6) and Interleukin-8 (IL-8) are among such myokines. This study was therefore taken up in 42 animals of Marwari, Kathiawari, Manipuri and Zanskari horses; and Poitou and Halari donkeys to find out the Single Nucleotide Polymorphisms (SNPs) in the IL-6 and IL-8 genes. Sequence analysis of exon 2 of IL-6 gene revealed an intronic SNP (C>T) at position Equcab3.0:4:54607583 in Poitou donkey. No SNP was detected in the equines covered in the study for IL-6 exon 5, exon 6 and their flanking sequences. However, in exon 1 of the IL-8 gene of all 4 horse breeds and 2 donkey breeds, a non-synonymous SNP (G > C) leading to a change in amino acid from leucine (L) to phenylalanine (F) (p. Leu10> p. Phe10) was observed at position EquCab3.0:3:63720817. Another nucleotide substitution was T>C in the intron 1-2 of IL-8 gene in all equids studied at position EquCab3.0:3:63720770. In addition to above two substitutions, in the 5' UTR of IL-8 gene in Poitou donkey, in place of guanosine (G), heterozygous condition S (C/G) was observed at position EquCab3.0:3: 63720883. This paper presents four SNPs with one non-synonymous SNP leading to a change in IL-8 protein sequence in equines.

Molecular characterization of Camelpox virus isolates from Bikaner, India: Evidence of its endemicity.

Camelpox is an important viral disease of camels, which may produce mild skin lesions or severe systemic infections. Camelpox virus (CMLV) isolates retrieved from an incidence of camelpox in camels at Bikaner, India were characterized on the basis of genotype and pathotype. Histopathological examination of the CMLV scab revealed intracytoplasmic-eosinophilic inclusion bodies. The phylogenetic analysis of all eight CMLV isolates for C18L gene nucleotide sequence revealed its clustering with its strains M-96 from Kazakhstan and CMS from Iran. The study will help to understand the transmission chain, pathobiology, and epidemiology of circulating CMLV strains. The full genome sequencing of some of the exemplary samples of CMLV is recommended in order to plan and implement a suitable control strategy.

Camelpox: A brief review on its epidemiology, current status and challenges.

Camelpox caused by a Camelpox virus (CMLV) is a very important host specific viral disease of camel. It is highly contagious in nature and causes serious impact on health even mortality of camels and economic losses to the camel owners. It manifests itself either in the local/mild or generalized/severe form. Various outbreaks of different pathogenicity have been reported from camel dwelling areas of the world. CMLV has been characterized in embryonated chicken eggs with the production of characteristic pock lesions and in various cell lines with the capacity to induce giant cells. Being of Poxviridae family, CMLV employs various strategies to impede host immune system and facilitates its own pathogenesis. Both live and attenuated vaccine has been found effective against CMLV infection. The present review gives a comprehensive overview of camelpox disease with respect to its transmission, epidemiology, virion characteristics, viral life cycle, host interaction and its immune modulation.

Genetic and demographic bottleneck analysis of Indian camel breeds by microsatellite markers.

The genetic and demographic bottleneck analysis of Indian camel breeds was carried out utilizing 40 microsatellite markers. Allelic polymorphism was observed at 20 loci in the Indian dromedary breeds. A total of 66 alleles were scored. The average number of alleles, expected heterozygosity and polymorphic information content were, respectively, 3.25 ± 0.27, 0.56 ± 0.04 and 0.49 ± 0.04 in Bikaneri; 3.25 ± 0.25, 0.53 ± 0.03 and 0.46 ± 0.03 in Jaisalmeri; 3.0 ± 0.21, 0.53 ± 0.04 and 0.45 ± 0.03 in Kachchhi and 3.1 ± 0.19, 0.51 ± 0.03 and 0.44 ± 0.03 in Mewari breed. Higher genetic variation was observed in most numerous Bikaneri breed. Genetic distances were least between the breed pair Bikaneri and Jaisalmeri which was closely placed with the Kachchhi breed. The Mewari camels had relatively higher genetic distance from the other three Indian dromedary breeds. The bottleneck analysis revealed the presence of genetic bottleneck in all four breeds of Indian dromedary. However, the qualitative graphical method resulted in normal L-shaped distribution of allele frequencies in Jaisalmeri breeds and shifted mode in Bikaneri, Kachchhi and Mewari breeds. The demographic bottleneck analysis revealed minimum reduction (-9.65 %) in the population of camels in Jaisalmeri breeding tract as compared to that of Bikaneri (-14.18 %), Kachchhi (-27.78 %) and Mewari (-32 %) breeding tracts. Conclusively, the genetic bottleneck analysis could explain the demographic bottleneck in the Indian dromedary populations. Therefore, appropriate conservation and improvement efforts are needed in all four dromedary breeds with immediate attention on Mewari and Kachchhi breeds. The present study is the first report in demonstrating the genetic basis of demographic bottleneck in the Indian dromedary populations.