The present study was conducted to evaluate resistance against ionophores (salinomycin and maduramicin) in four field isolates (F) of Eimeria tenella collected from four distantly located poultry farms from Union territory of Jammu and Kashmir. The purity of isolates was ascertained by COCCIMORPH and ITS-1 gene amplification for E. tenella. For the drug sensitivity trial, Cobb strain, day-old male broiler chicks were used. At the age of 10 days, the birds were transferred ad random in 13 groups to battery cage system. All birds, except non infected non-medicated control were infected with 105 sporulated oocysts each at two weeks. Prophylactic medication with ionophores commenced two days prior to infection in eight groups (two medicated groups for each of the four isolates). Another four groups served as infected and non-medicated control. Seven days post infection, all the surviving birds were sacrificed to study drug resistance by assessing the global index for individual ionophore compounds. The F-1 exhibited resistance against salinomycin and maduramicin whereas, the F-2 showed comparatively improved global index for both salinomycin and maduramicin thus indicating limited efficacy. The F-3 exhibited partial resistance against salinomycin and limited efficacy in case of maduaramicin, and the F-4 was observed to be resistant against salinomycin whereas partially resistant against maduramicin. The present study provides evidence of resistance against maduramicin and salinomycin in field isolates of E. tenella from Union Territory of Jammu and Kashmir which may aid in management of poultry coccidiosis.

The present study was conducted from January 2018 to December 2019 to know the prevalence of coccidiosis in backyard poultry in Jammu, Samba, and Udhampur districts of Union Territory of Jammu and Kashmir, North India. A total of 600 pooled fecal samples collected from backyard poultry were examined for presence of Eimeria oocysts. Morphometry and Polymerase Chain Reaction (PCR)-based amplification of ITS-1 gene was carried to characterize the Eimeria species infecting the backyard poultry of the study area. An overall prevalence of 28.5% Eimeria spp. infection among backyard poultry birds was recorded. Among the seasons, highest prevalence was recorded during rainy season (32%) with significantly (p < 0.05) high oocyst excretion (1.77 ± 0.01) and lowest during summer (19.3%) with low oocyst excretion (0.17 ± 0.006). Young birds up to 3 months of age were found to be more susceptible to infection than older birds, with a significantly (p < 0.05) high prevalence percentage of 38.02. Morphometry with COCCIMORPH software revealed presence of Eimeria tenella, Eimeria necatrix, Eimeria acervulina, and Eimeria maxima species with prevalence rates of 27.6%, 21.3%, 16.5%, and 3.6%, respectively. The amplified fragments of ITS-1 gene presented different sizes of Eimeria spp. viz. E. acervulina (321 bp), E. tenella (278 bp), E. maxima (145 bp), and E. necatrix (383 bp). The study concluded that although backyard poultry did not show clinical form of coccidiosis, it may act as source of potential reservoir.