Salmonella Serovars Isolated from Poultry Breeding Flocks under the Brazilian Official Control Programme Between 2016 and 2018

The control of Salmonella in the poultry production chain combined with biosecurity measures is an important tool to maintain and guarantee the sanitary status of Brazilian flocks. The aim of this work was to compare official laboratory data on molecular typification of Salmonella isolates from poultry breeding flocks in different Brazilian states between 2016 and 2018 and identify the production category with the most positive flocks, in light of current legislation. Surveillance data of positive samples from the official Brazilian Salmonella Control Programme sent to Federal Agricultural Defence Laboratory of São Paulo (LFDA-SP) after molecular characterization were analysed. These data were subject to an exploratory study, undergoing a descriptive statistical analysis followed by the use of frequency and non-parametric hypothesis tests. Overall, 49 serovars were detected in poultry broiler-breeder and layer-breeder flocks. Salmonella ser. Heidelberg, Salmonella ser. Anatum, Salmonella ser. Newport, Salmonella ser. Schwarzengrund and Salmonella ser. Mbandaka were the five most common isolated serovars. The data shows that there is an opportunity to improve biosecurity measures in parent breeder flocks. A total of 16 serovars were identified in turkey-breeders. Salmonella ser. Anatum, Salmonella ser. Newport, Salmonella ser. Brandenburg, Salmonella ser. Litchfield, and Salmonella ser. Livingstone were the most common ones. The four official controlled serovars represented a small part of the isolated strains. These data demonstrate the importance of an official program in Brazil for Salmonella surveillance in breeder flocks combined with biosecurity measures.(AU)

Multidrug resistance in Shiga toxin-producing Escherichia coli (STEC) isolated from broiler chickens at slaughter / Resistência a múltiplos antimicrobianos em Escherichia coli shigatoxigênica (STEC) isoladas de frangos de corte ao abate

Broiler chickens and derived products are a key source of Shiga toxin-producing Escherichia coli (STEC) in humans. This pathotype is responsible for causing severe episodes of diarrhea, which can progress to systemic complications. A rapid and accurate diagnosis of the disease, and early treatment of the infection with antimicrobials, can prevent it worsening. However, multidrug-resistant strains have potentially negative implications for treatment success. In this context, the aim of the present study was to isolate and identify multidrug-resistant STEC strains from broiler chickens and carcasses. Of 171 E. coli strains, isolated by conventional microbiological techniques and submitted to Polymerase Chain Reaction (PCR), for detection of stx1 and stx2 genes, 21.05% (36/171) were STEC pathotype, and most of them (66.67% - 24/36) carried both stx1 and eae genes. The multidrug resistance pattern was observed in 75% (27/36) of STEC strains. The presence of STEC in broiler chickens and carcasses reinforces that these sources may act as reservoirs for this pathotype. Multidrug-resistant bacteria contaminating animal products represent a public health issue because of the possibility of spread of multidrug-resistant determinants in the food chain and a higher risk of failure in human treatment when antimicrobials are needed.(AU)

Frangos de corte e seus produtos são importantes componentes na cadeia de transmissão de Escherichia coli do patotipo Shigatoxigênico (STEC) para humanos. Este patotipo é responsável por causar episódios de diarréia severos, que podem evoluir para complicações sistêmicas. O diagnóstico rápido e preciso da doença, e o tratamento com antimicrobianos ainda no início da infecção, podem evitar seu agravamento. Porém, cepas resistentes a múltiplos antimicrobianos podem ter implicações potencialmente negativas em relação ao sucesso do tratamento. Neste contexto, este estudo teve como objetivo isolar e identificar cepas STEC resistentes a múltiplos antimicrobianos em frangos de corte e carcaças. Das 171 cepas de E. coli isoladas pelo método bacteriológico convencional, e submetidas à Reação em Cadeia da Polimerase (PCR), para detecção dos genes stx1 e stx2, 21.05% (36/171) pertenciam ao patotipo STEC, a maioria (66.67% - 24/36) portando o gene stx1 associado ao gene eae. O perfil de multirresistência foi observado em 75% (27/36) das cepas STEC. A presença de cepas STEC no material estudado reforça o fato de que frangos vivos e carcaças devem ser considerados como reservatórios deste patotipo. A presença de cepas resistentes a múltiplos antimicrobianos, contaminando produtos de origem animal, representa um risco à Saúde Pública pela possibilidade de disseminação de determinantes de multirresistência e maior risco de insucesso no tratamento de indivíduos infectados.(AU)