Intestinal Microbiome Profiles in Broiler Chickens Raised with Different Probiotic Strains.

The composition of the intestinal microbiota can influence the metabolism and overall functioning of avian organisms. Therefore, the objective of this study was to evaluate the effect of three different probiotics and an antibiotic on the microbiomes of 1.400 male Cobb® broiler raised for 42 days. The experiment was conducted with the following treatments: positive control diet (basal diet + antibiotic); negative control diet (basal diet without antibiotic and without probiotic); basal diet + Normal Avian Gut Flora (NAGF); basal diet + multiple colonizing strain probiotics (MCSPs); and basal diet + non-colonizing single strain probiotics (NCSSPs). The antibiotic (enramycin-antibiotic growth promoter) and probiotics were administered orally during all experiment (1 to 42 days), mixed with broiler feed. To determine the composition of the microbiota, five samples of ileal digesta were collected from 42-day-old chickens of each experimental group. The alpha and beta diversity of the ileal microbiota showed differences between the groups. MCSPs presented greater richness and uniformity compared to the positive control, negative control, and NCSSPs treatments, while the negative control exhibited greater homogeneity among samples than NCSSPs. MCSPs also showed a higher abundance of the genus Enterococcus. There were differences between the groups for low-abundance taxa (<0.5%), with NAGF showing higher levels of Delftia, Brevibacterium, and Bulleidia. In contrast, NCSSPs had a higher abundance of Ochrobactrum, Rhodoplanes, and Nitrospira. It was concluded that the treatments analyzed in this study induced modulations in the ileal microbiota of the chickens examined.

Immunostaining and gene expression of epidermal growth factor receptors (HER1/HER2) in canine cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is a neoplasm type often diagnosed in dogs. However, studies focused on further investigating its molecular biology, mainly biomarkers to help implementing new therapies, remain scare in the literature. Thus, immunostaining and the gene expression of epidermal growth factor receptors (HER1 and HER2) in canine cSCC presenting different cell differentiation degrees were herein assessed. Thirty-two (32) canine cSCC were selected, classified based on to their cell differentiation degree and subjected to immunohistochemical study to assess HER1 and HER2 immunostaining intensity and distribution. In addition, HER1 and HER2 gene expression was investigated through real-time PCR. Membranous and cytoplasmic immunostaining were observed in both markers. HER2 prevailed in poorly differentiated cSCC; there was positive protein expression correlation between both markers. Mean HER1 gene expression was higher in moderately differentiated, whereas mean HER2 gene expression was higher in poorly differentiated cSCC. Moreover, there was gene expression correlation between markers, regardless of cell differentiation degree. Thus, HER2 protein immunostaining and gene expression were higher in poorly differentiated canine cSCC and it enabled understanding that increase observed in this epidermal growth factor receptor is proportional to this neoplasm's cell differentiation degree in canine species. Results in the current study helped better understanding canine cSCC's molecular biology; however, it is relevant studying other markers aiming to investigate signaling pathways.

Antibiotic Resistance Profile of Salmonella sp. Isolates from Commercial Laying Hen Farms in Central-Western Brazil.

Microbial resistance to antibiotics poses a significant threat to both human and animal health, necessitating international efforts to mitigate this issue. This study aimed to assess the resistance profiles of Salmonella sp. isolates and identify the presence of intl1, sul1, and blaTEM resistance genes within antigenically characterized isolates, including Agona, Livingstone, Cerro, Schwarzengrund, Salmonella enterica subsp. enterica serotype O:4.5, Anatum, Enteritidis, Johannesburg, Corvallis, and Senftenberg. These isolates underwent susceptibility testing against 14 antibiotics. The highest resistance percentages were noted for sulfamethoxazole (91%), sulfonamides (51%), and ceftiofur (28.9%), while no resistance was observed for ciprofloxacin. Salmonella Johannesburg and Salmonella Corvallis showed resistance to one antibiotic, whereas other serovars were resistant to at least two. Salmonella Schwarzengrund exhibited resistance to 13 antibiotics. The intl1 gene was detected in six out of the ten serovars, and the sul1 gene in three, always co-occurring with intl1. The blaTEM gene was not identified. Our findings highlight the risk posed by the detected multiple resistances and genes to animal, human, and environmental health. The multidrug resistance, especially to third-generation cephalosporins and fluoroquinolones, highlights the need for stringent monitoring of Salmonella in laying hens. The potential of the environment, humans, eggs, and their products to act as vectors for antibiotic resistance represents a significant concern for One Health.