ABSTRACT

Antimicrobial resistance (AMR) is a worldwide health concern and use of antimicrobials in animal production is a major cause of AMR in humans. This study was conducted to determine factors that influence choice and application of antibiotics by broiler farmers in Abia State-Nigeria by administration of structured questionnaires to 100 farms. The study also evaluated antimicrobial resistance profile of bacteria isolated from broiler-chicks in the Abia State by conducting antimicrobial sensitivity test to ten antimicrobials commonly used in poultry farming in Abia State and developed a treatment-strategy for prevention of AMR and for curing already resistant infections of salmonella paratyphoid by stabilizing Streptomycin with Medicinal Synthetic Aluminium Magnesium Silicate. All 56 poultry farms that responded to questionnaires administered to them accepted that they use antibiotics on their farms. 67% of the farmers in Abia State were males, with first degree (34.5%) small-scale farmers (46%), keeping broilers (70%) in deep litter system (70%). They said that drugs they use to treat their birds are as prescribed by Veterinary Doctors (76.4%). Drug-formulations containing tetracycline (90%) are the ones most of them use. 70.4% of the farmers had good knowledge of laws regulating use of antibiotics in raising food animals. They also know the problem of Antimicrobial resistance. Of a total of 180 samples tested, 21% yielded presumptive Salmonella isolates in cultures with the two commonly encountered zoonoses, S. typhimurium and S. enteritidis respectively, accounting for 2.63% (1) and 97.36% (37) isolates of the Salmonella isolates when serotyped. The S. tyhimurium isolate was Multi-drug resistant (MDR) being sensitive to only Ciprofloxacin. Clinical signs observed when the MDR S. typhimurium was used to challenge 3-weeks old broiler-chicks were fever, watery-mucoid diarrhea, drop in feed consumption and reluntance to move with a mortality rate of 19 %. Post mortem examination of the S. typhimuruim infected broiler chicks revealed hepatomegaly with necrotic foci, enlarged spleen and enteritis. Recommended dose of Streptomycin (25mg/kg) could not cure the infection but when the drug was stabilized with Medicinal synthetic Aluminum magnesium silicate and was supported with Vitamin C (through feed) 75% of the recommended dose (18.75 mg/kg) cleared the resistant infection (100 % infection-reduction). The recommended dose even led to increase of the infection-load (-787.4% reduction) more than -656% infection-reduction of the untreated group, suggesting that Streptomycin treatment worsened the resistant infection. Survivors of the MDR S. typhimurium infection which were fed feed fortified with additional levels of Vitamin C attained a dressed weight of 1.5kg at 44days and higher cost of producing 1 kg of chicken (Ꞥ1,175.15) when compared with 1.5kg attained at 40 days at a cost of Ꞥ955.60/kg of chicken of the group of uninfected chicks fed with same feed with the additional Vitamin C supplementation..