The aim of this study was to estimate the residue levels of five commonly used antibiotics in poultry tissue samples using enzyme linked immunosorbent assay (ELISA). A total of 200 samples that comprised breast and liver (100 each) were collected from five poultry farms randomly selected from Muscat regions. The samples were analyzed for enrofloxacin (ENR), gentamicin (GEN), oxytetracycline (OTC), sulfamethazine (SMZ), and tylosin (TYL) residue concentrations. Comparisons of antibiotic residues between breast and liver of chickens under investigations showed a significant difference of ENR, GEN, OTC, SMZ, and TYL residue concentrations (p < 0.05). The highest antibiotic residue concentrations reported in the chicken liver were TYL, GEN, OTC, SMZ, and ENR, respectively. The lowest residual antibiotic concentrations observed in the chicken breast were TYL, GEN, OTC, SMZ, and ENR, respectively. Furthermore, the Kruskal–Wallis statistical test revealed a significant difference between the five antibiotic concentrations in both breast (H (4) = 54.69, p < 0.05) and liver (H (4) = 44.36, p < 0.05). A follow up of this finding by Bonferroni correction for both breast and liver samples revealed a significant difference for the breast sample between the concentration of ENR residue, and the concentration of residues for of both OTC and TYL (p < 0.05). These data show that not all tissues incorporate antibiotics at the same concentration. The results of this study could support regulatory bodies in adopting, monitoring, and enforcing guidelines pertinent to safety levels of different antibiotic residue concentrations in poultry meat when antibiotics are used for different indications.

Jabal Akhdar goats, native to Oman’s high-altitude Jabal Akhdar mountain range, are recognized for their high growth rate, remarkable twinning rate, and adaptability to harsh environmental conditions. This study assesses the genetic structure, inbreeding levels, effective population size (N_e), and linkage disequilibrium (LD) of Jabal Akhdar goats while identifying genomic regions under positive selection that may contribute to their environmental adaptation. The SNP genotypes from 72 Jabal Akhdar goats and two desert breeds from Egypt (153 Barki and 60 Saidi) revealed a clear genetic distinction between both groups. Within the Jabal Akhdar goats, genetic differentiation was also identified among the three sampled villages, indicating a village-specific genetic structure. The Jabal Akhdar breed exhibited a moderate level of inbreeding (F_ROH = 0.16), greater than that of the Barki and Saidi breeds. Additionally, Jabal Akhdar goats displayed greater LD and lower N_e levels compared to the Egyptian breeds. Analysis of runs of homozygosity (ROH) and extended haplotype homozygosity-based statistics (iHS and Rsb) identified 93 genomic regions exhibiting signatures of positive selection (80 from ROH, 5 from iHS, and 8 from Rsb). These regions harbor genes associated with traits essential for environmental adaptability, including hypoxia tolerance (SUCNR1, ANGPTL1, MITF, MTUS2), muscle development and function (MBNL1, ACTC1, CAPN5), fertility (GNRHR, CCNA1, SPAG1), UV radiation resistance (UVRAG, BRCA1), bone development (SOST, MEOX1), and lipid metabolism for energy utilization (DGAT2, G6PC, SUCLG2). The results of this study provide valuable insights for identifying causative variants and haplotypes underlying the Jabal Akhdar goat’s superior adaptability. These findings can guide breeders in designing conservation strategies and improving the productivity of this unique indigenous breed.

Background and Aim: Epizootic hemorrhagic disease virus (EHDV), an Orbivirus transmitted by Culicoides midges, infects a wide range of ruminant species including dromedary camels (Camelus dromedarius). Although circulation of EHDV has been documented in cattle in the Sultanate of Oman, its epidemiology in camels remains poorly characterized. This study was conducted in the Al Batinah North and Al Batinah South governorates, coastal regions with hot, arid climates favorable to vector activity, to estimate individual-level seroprevalence of EHDV antibodies in dromedary camels, identify associated risk factors using univariate and multivariate analyses, and evaluate spatial distribution patterns to inform future control measures in multi-host livestock systems. Materials and Methods: A cross-sectional study was performed between September 2020 and July 2021. Serum samples were collected from 415 camels across 50 holdings using convenience sampling. Antibodies against EHDV were detected with a commercial competitive enzyme-linked immunosorbent assay (c-ELISA) targeting the VP7 protein (sensitivity = 85.9 %, specificity = 99.7 %). True prevalence (TP) was calculated using the Rogan–Gladen estimator. Univariate associations were assessed with chi-square or Fisher’s exact tests; variables with p < 0.25 were entered into backward stepwise binary logistic regression. Spatial analyses included average nearest-neighbour clustering, Getis-Ord Gi* hot-spot analysis, and kernel density estimation in ArcGIS. Results: Apparent seroprevalence was 40.2 % (95 % confidence interval [CI]: 35.5–45.1 %), with an estimated TP of 46.7 % (95 % CI: 41.3–52.3 %). No significant difference existed between governorates (p = 0.520). In univariate analysis, seropositivity was significantly higher in camels > 4 years of age (45.9 % vs 19.3 %; p < 0.001), in breeding/leisure camels (43.1 % vs 20.8 %; p = 0.002), and in animals kept in contact with other ruminants (49.3 % vs 35.6 %; p = 0.007). After multivariate adjustment, only age > 4 years (odds ratio [OR] = 3.4, 95 % CI: 1.88–5.96; p < 0.01) and contact with other ruminants (OR = 1.6, 95 % CI: 1.05–2.44; p = 0.029) remained independent risk factors. Global spatial clustering of positive holdings was highly significant (nearest-neighbour ratio = 0.39, z = –8.26, p < 0.001), with elevated density along coastal agricultural corridors. Conclusion: This first large-scale serological survey confirms active circulation of EHDV among dromedary camels in northern Oman. Older age and mixed-species herding are the main risk factors identified. The findings highlight the importance of camels in the multi-host ecology of EHDV and emphasize the need for integrated national surveillance, vector studies, and molecular characterization of circulating serotypes to support evidence-based control strategies in a changing climate. Keywords: dromedary camels, EHDV antibodies, epizootic hemorrhagic disease, northern Oman, risk factors EHDV, seroprevalence study, spatial clustering EHDV.