Sources of infection and antimicrobial susceptibility profile of Salmonella sp. isolated in broiler production flow

Abstract

This work aimed at searching for Salmonella in liver, heart, yolk sac and meconium samples of one-day-old chicks, crops and cecum samples from slaughterhouses and drag swabs and Alphitobius diaperinus larvae or adults. It also aimed at determining the susceptibility profile to amoxicillin (10 mcg), ampicillin (10 mcg), ciprofloxacin (5 mcg), enrofloxacin (5 mcg), florfenicol (30 mcg), neomycin (30 mcg), sulfonamide (300 mcg), tetracycline (30 mcg) and trimethoprim-sulfamethoxazole (25 mcg) of typed serovars isolated. The samples were submitted to microbiological analyses by the conventional method. Salmonella sp. was isolated in 4.7% (12/256) of samples of one-day old chicks, in 6.2% (4/64) of the liver, 4.7% (3/64) of the hearts, 3.1% (2/64) of the yolk sacs, 4.7% (3/64) of meconium, and in10.2% (13/128) of the environment samples, being 9.4% (9/96) from drag swabs, 12.5% (4/32) from larvae and adult Alphitobius diaperinus and 4.4% (28/640) of the slaughterhouses samples, being 6.5% (21/320) of crops and 2.2% (7/320) of cecum samples. Salmonella enterica ser. Enteritidis was identified only in drag swabs and Alphitobius diaperinus. Salmonella enterica ser. Typhimurium was observed in the crops and cecum, which have shown high frequency of resistance to sulfonamides, 75% (6/8) and100% (3/30), respectively. Additionally, 20.7% (11/53) of the serovars have shown multiresistance to at least two of the tested drugs. In conclusion, Salmonella can be widely spread in broiler production flow, and the vertical pathway is still a major source of Salmonella insertion in the poultry production chain. The litter and bugs can perpetuate and disseminate Salmonella sp.