Nucleotide sequence variations, gene expression profiles, and host biomarkers associated with ovine mange caused by Sarcoptes and Psoroptes mites: implications for diagnosis and disease control

Abstract

Introduction Ovine mange is a highly contagious skin disease that causes substantial economic losses. This study assessed the prevalence, SNPs, gene expression, serum APPs, and immune and antioxidant markers to elucidate the immunological and oxidative mechanisms of mange in Barki sheep. Methods A total of 320 adult Barki ewes were enrolled in the study, comprising 80 clinically affected animals and 240 apparently healthy controls. Blood samples were collected from all animals for the determination of acute-phase proteins, immunological and antioxidant biomarkers, and gene expression analyses of CARD9, CLEC7A, TNFAIP3, IL33, SESN2, ATF4, HSPA1A, and SLC7A11. Only clinically affected sheep underwent parasitological confirmation by microscopic examination of deep skin scrapings collected from active skin lesions to identify mange mites. Results Microscopic examination confirmed mange in 25% (80/320) of the ewes, with Sarcoptes spp. accounting for 75% and Psoroptes spp. for 25% of the cases. Infected sheep showed upregulation of CARD9, CLEC7A, IL33, SESN2, ATF4, and HSPA1A, and downregulation of TNFAIP3 and SLC7A11 (p < 0.05), with 14 SNPs differing significantly between the healthy and infected groups. Infected animals showed elevated APPs, pro-inflammatory cytokines, and oxidative stress, with reduced IL-10 levels. Conclusion Ovine mange is associated with distinct molecular, immunological, and oxidative stress responses that reflect the host’s reaction to mite infestation. To our knowledge, this is the first study to integrate transcriptional profiling with SNP characterization of CARD9, CLEC7A, TNFAIP3, IL33, SESN2, ATF4, HSPA1A, and SLC7A11 in naturally occurring ovine mange. The identified sequence variants, together with gene expression signatures, provide novel candidate molecular biomarkers for disease susceptibility and may support future genetic selection and precision disease management strategies. Additional studies involving larger and independent sheep populations are needed to validate these findings and determine their potential value in disease susceptibility assessment and genetic improvement programs.