Prevalence of Salmonella spp. in broiler chicken flocks in northern Poland in 2014–2016

Zoonotic serotypes of Salmonella enterica subsp. enterica are an important biological factor that poses a threat to public health, and broilers are often asymptomatic carriers of these bacteria. The aim of this study was to analyze the prevalence of Salmonella spp. and Salmonella serotypes in broiler chicken flocks in northern Poland in 2014–2016. The study was conducted on commercial flocks monitored by the Institutes of Veterinary Hygiene in Gdańsk and Olsztyn in 2014–2016. A total of 4,331 samples were investigated. Identification of Salmonella spp. was performed by a culture-dependent method followed by biochemical and serological confirmation tests, in accordance with Polish Standards. The total percentage of infected flocks in northern Poland reached 1.57%. The prevalence of Salmonella spp. in broiler chickens decreased from 2.19% in 2014 to 1.22% in 2016. The percentage of flocks infected with S. Enteritidis and S. Typhimurium was 1.18% and 0.12%, respectively (S. Enteritidis and S. Typhimurium were detected in 1.29% of flocks). The most common serotypes that had not been covered by the control programme were S. Mbandaka (0.14%), S. Infantis (0.07%) and, sporadically, S. Kentucky and S. Anatum. The percentage of infected flocks was higher (by 0.26%) in the Pomeranian Region than in the Region of Warmia and Mazury, and it increased over the analyzed period – the highest number of positive samples were found in 2016 (2.04%). In the Region of Warmia and Mazury, the percentage of infected flocks was highest in 2014 (3.08%); in 2014–2016, the number of positive samples decreased steadily to reach 0.41% in 2016. In the analyzed regions, the incidence of human salmonellosis was correlated with the percentage of infected broiler flocks

Homeostasis of the Intestinal Mucosa in Healthy Horses—Correlation between the Fecal Microbiome, Secretory Immunoglobulin A and Fecal Egg Count

The defensive function of the intestinal mucosa depends both on the ability to secrete immunoglobulin A and communication with the mucus microbiome. In horses, the functioning of this system is also influenced by the presence of nematode eggs. Feces collected from healthy horses were examined to determine the fecal egg count, immunoglobulin A level (ELISA), microbiome composition (Next-Generation Sequencing, NGS, V3–V4 and V7–V9 hypervariable regions of the 16S rRNA gene analysis and short-chain fatty acid (SCFA) production ((high-performance liquid chromatography, HPLC). In the taxonomic analysis within the phylum, the following order of dominance was found: Firmicutes, Bacteroidota, Verrucomicrobiota and Fibrobacterota. The coefficient of phylogenetic diversity of the microbiome positively correlated with both secretory immunoglobulin A (SIgA) [μg/g of feces] (p = 0.0354, r = 0.61) and SIgA [μg/mg of fecal protein] (p = 0.0382, r = 0.6) and with the number of Cyathostomum eggs (p = 0.0023, r = 0.79). Important components of the key microbiome in horses, such as phylum Proteobacteria and species Ruminococcus flavefaciens, were positively correlated with the fecal SIgA (p < 0.05). All the obtained results indicate the existence of significant relationships between the host response (SIgA production) and composition and SCFA production in the microbiome as well as the presence of small strongyles in the digestive tract of horses