The objective of this study was to describe two clinical cases of toxicosis by accidental administration of salinomycin in feed in broiler breeders and turkeys. In the first clinical case, a 32000 broiler breeders flock, 30 weeks of age, suffered a severe mortality during the first week, a sharp decrease in egg production and a dramatic reduction in food consumption together with an increase of eating time. The pathological condition manifested itself mainly with leg paralysis and reluctance to move. In necropsy, signs of bile hyper-secretion, absence of feed in the digestive tract, liver degeneration, egg peritonitis, enlarged kidneys and spleen atrophy were found. Serological examinations for IBV, IBD, NDV, Mg, Ms, Ort, TRT, AE and CAA were negative. The broiler breeders flock was finally euthanized due to an irreversible condition, slow recovery and poor production indicators. In the second clinical case, a flock of 27000 turkeys fatteners, aged from 20 to 35 days, showed an increased daily mortality up to 10 and a 88% total death loss in 2 weeks period. The turkeys showed great growth retardation, reluctance to move and eat, ataxia and absence of gross lesions, except atrophy of the spleen and pica. Serological examinations for NDV and AI were negative. After removal and change of feed, the remaining flock recovered normally. These two clinical cases were initially associated with incorrect diet and, after obtaining detailed clinical history, laboratory tests and food analysis, the by error administration of salinomycin in feed was confirmed. The final concentrations of salinomycin in feed analysis reached 64.6-124 mg kg^-1 for the broiler breeders and 298-944 mg kg^-1 for turkeys. While salinomycin toxicosis has been reported worldwide in the literature in a number of animal species, including turkey breeders and fatteners with similar symptoms, in broiler breeders has never been reported on the field

The aim of this report was to describe a clinical case of concurrent infection with Mycoplasma Gallisepticum (MG) and Mycoplasma Synoviae (MS) in layers, complicated with Escherichia coli and Pasteurella multocida, as well as to evaluate the efficacy of tylosin tartrate treatment (Pharmasin ® 100% WSG, Huvepharma) on Mycoplasma under field conditions. A flock of 18,500 ISA Brown pullets, 21 weeks of age and MS positive, showed an increase in weekly mortality, with no influence on egg production. At 24 weeks of age, post mortem was carried out and blood samples were collected, as well as samples for microbiological cultures from the lesions. In necropsy, several findings of pericarditis, airsacculitis of posterior thoracic sacs, prolapse and egg yolk peritonitis were found. Sporadic neurological signs were also apparent and post mortem examination revealed yellow caseous exudate accumulations in cranial bones. Although egg production was not influenced, Eggshell Apex Abnormalities (EAA) were increased with a significant number of both broken and misshapen eggs together with discoloration. Elisa serological examinations for Infectious Bronchitis Virus (IBV) and Newcastle Disease Virus (NDV) were within vaccination program limits, but MS, MG and Avian Rhinotracheitis (ART) results showed a significant seroconversion. Microbiology also revealed the presence of Escherichia coli and Pasteurella multocida. On week 25, a drug treatment with tylosin tartrate was applied at a dose of 105 mg kg −1 body weight in drinking water for five consecutive days. Three days after treatment, misshapen, broken and discolored eggs were decreased. The mortality was also significantly decreased within a week since the beginning of tylosin administration and at 30 weeks of age was within acceptable levels. Post mortem evaluation confirmed the absence of previously gross lesions in primary organs. In summary, tylosin treatment in complicated Mycoplasma spp. infections under field conditions improved egg shell quality and decreased mortality, thus the economic losses linked to decreased egg production and labor costs were reduced.