Analysis of Genome DNA Methylation at Inherited Coat Color Dilutions of Rex Rabbits

Background: The dilution of color in rabbits is associated with many different genetic mechanisms that form different color groups. A number of previous studies have revealed potential regulatory mechanisms by which epigenetics regulate pigmentation. However, the genome-wide DNA methylation involved in animal coat color dilution remains unknown.Results: We compared genome-wide DNA methylation profiles in Rex rabbit hair follicles in a Chinchilla group (Ch) and a diluted Chinchilla group (DCh) through whole-genome bisulfite sequencing (WGBS). Approximately 3.5% of the cytosine sites were methylated in both groups, of which the CG methylation type was in greatest abundance. In total, we identified 126,405 differentially methylated regions (DMRs) between the two groups, corresponding to 11,459 DMR-associated genes (DMGs). Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that these DMGs were principally involved in developmental pigmentation and Wnt signaling pathways. In addition, two DMRs were randomly selected to verify that the WGBS data were reliable using bisulfite sequencing PCR, and seven DMGs were analyzed to establish the relationship between the level of DNA methylation and mRNA expression using qRT-PCR. Due to the limitation of small sample size, replication of the results with a larger sample size would be important in future studies.Conclusion: These findings provide evidence that there is an association between inherited color dilution and DNA methylation alterations in hair follicles, greatly contributing to our understanding of the epigenetic regulation of rabbit pigmentation.

ERGONOMIC PROPERTIES OF THE SEMI-FINISHED SHORT HAIRY RABBIT FUR PRODUCT

The article is dedicated to the study of the ergonomic properties of the semi-finished short-haired rabbit fur, which determine the technological possibilities of fur. It is shown that the semi-finished rabbit of rex breed of colour castor and chinchilla has equal resistance to moisture when wet, which is indicated by the moisture content index. When testing hygroscopicity, it is established that the skin samples with hair are less hydrophilic than those without it; by 12,5 %, in the rabbit skins of the rex castor breed, and by 13,8 %, in the skins of the rabbit of rex chinchilla breed. The total thermal resistance of a semi-finished rex rabbit product exceeds the value of the feature of 0,210 m2 ·ºC/W, which makes it one of the group of semi-finished fur products with high thermal protection properties. The established indicators of ergonomic properties of a semi-finished rex rabbit product should be taken into account when choosing semi-finished products and creating furs of different designs and silhouettes.

Disparate histopathology of sebaceous adenitis in a rabbit

A 13-month-old, spayed, female rex rabbit presented with mildly pruritic, progressive patches of alopecia, erythema and scaling of the head, trunk and legs of five months’ duration. Initial skin biopsy was consistent with cutaneous epitheliotropic lymphoma, but a follow-up skin biopsy and response to therapy revealed that the rabbit actually had sebaceous adenitis. Nearly one year after presentation, the rabbit’s clinical signs remained well controlled. This case demonstrates the importance of interpreting histopathology in light of history, physical examination, supportive tests and response to therapy. It also demonstrates how cutaneous lesions may evolve over time and that serial biopsies may be required to achieve a diagnosis. Finally, this case suggests that there may be histopathological overlap between cutaneous epitheliotropic lymphoma and sebaceous adenitis in rabbits.