Dietary supplementation with hydrolyzed yeast and its effect on the performance, intestinal microbiota, and immune response of weaned piglets.

The objective of this study was to evaluate the effects of autolyzed yeast on performance, cecal microbiota, and leukogram of weaned piglets. A total of 96 piglets of commercial line weaned at 21-day-old were used. The experimental design was a randomized block design with four treatments (diets containing 0.0%, 0.3%, 0.6%, and 0.9% autolyzed yeast), eight replicates, and three animals per pen in order to evaluate daily weight gain, daily feed intake, and feed conversion in periods of 0 to 15, 0 to 26, and 0 to 36 days. Quadratic effects of autolyzed yeast inclusion were observed on the feed conversion from 0 to 15 days, on daily weight gain from 0 to 15 days, 0 to 26 days and, 0 to 36 days, indicating an autolyzed yeast optimal inclusion level between 0.4% and 0.5%. No effect from autolyzed yeast addition was observed on piglet daily feed intake, cecal microbiota, and leukogram; however, i.m. application of E. coli lipopolysaccharide reduced the values ​​of total leukocytes and their fractions (neutrophils, eosinophils, lymphocytes, monocytes, and rods). Therefore, autolyzed yeast when provided at levels between 0.4% and 0.5% improved weaned piglets' performance.

Listeria monocytogenes From Farm to Fork in a Brazilian Pork Production Chain.

ABSTRACT: Listeria monocytogenes contamination was assessed in different steps of a pork production chain. Ten lots of pigs were sampled at termination barns, at slaughter (after bleeding, after buckling, after evisceration, and after final washing), at processing (knives, deboning tables, and employees' hands), and of end products (ribs, shoulder, ham, and sausage). All samples (n = 670) were subjected to L. monocytogenes detection, and the obtained isolates (n = 18, identified as Listeria spp.) were characterized by their biochemical characteristics, serogroups, virulence genes, pulsed-field gel electrophoresis profiles, antibiotic resistances (ampicillin, penicillin, gentamicin, and sulfamethoxazole-trimethoprim), and adhesion abilities. The results revealed the low occurrence of Listeria spp. in the evaluated pork production chain. However, four tested sausage samples (40%) were positive for Listeria spp., with L. monocytogenes identified in two (20%) of these samples. Ten isolates were identified as L. monocytogenes (eight from serogroup 1/2a or 3a and two from serogroup 4b, 4d, or 4e): all isolates were also positive for the virulence-related genes hlyA, iap, plcA, actA, inlA, inlB, inlC, and inlJ and susceptible to the tested antibiotics. One sausage sample was contaminated by both serogroups 1/2a or 3a and 4b, 4d, or 4e. Isolates from serogroup 1/2a or 3a obtained during visits 5 and 6 presented distinct genetic profiles by pulsed-field gel electrophoresis, indicating that contamination may come from different sources. The adhesion potential exhibited by Listeria spp. isolates (n = 18) ranged from weak (serogroup 4b, 4d, or 4e) to moderate (L. innocua and L. monocytogenes serogroup 1/2a or 3a). Despite the low occurrence of L. monocytogenes, pathogenic serogroups were detected in sausages, demanding control measures by the industry.

Identification and characterization of atypical enteropathogenic and Shiga toxin-producing Escherichia coli isolated from ground beef and poultry breast purchased in Botucatu, Brazil.

Atypical enteropathogenic (serotypes O4:H16, O8:H25, O68:H2, O105:H7, and OR:H25) and Shigatoxigenic (ONT:H46) Escherichia coli were isolated from samples of ground beef and poultry breast purchased in Botucatu, Brazil. Phenotypic and molecular characterization indicated the potential of these isolates to adhere to host epithelial cells and cause damage.

Detection of Ehrlichia canis, Babesia vogeli, and Toxoplasma gondii DNA in the Brain of Dogs Naturally Infected with Leishmania infantum.

The aims of this study were to investigate the presence of Leishmania infantum and possible co-infection with Anaplasma platys , Babesia vogeli, Ehrlichia canis , and Toxoplasma gondii in the brain of 24 dogs naturally infected by L. infantum . A total of 24 mongrel adult dogs (22 clinically affected, 2 with neurological signs, and 2 subclinically infected) aged between 2 and 5 yr, naturally infected by visceral leishmaniasis, were selected. Fragments from meninges, frontal cortex, thalamus, cerebellum, and choroid plexus of the lateral ventricles and fourth ventricle were collected, mixed, and tested by real-time polymerase chain reaction (qPCR). Leishmania infantum DNA was detected in 95.8% (23/24) of the infected dogs, including the subclinically infected. A total of 14/24 (58.3%) dogs were co-infected by E. canis and L. infantum , 4/24 (16.7%) were co-infected by E. canis , B. vogeli, and L. infantum , 2/24 (8.3%) were co-infected by B. vogeli and L. infantum , and 1/24 (4.2%) dog was co-infected by E. canis , B. vogeli, T. gondii , and L. infantum . All 24 brain samples tested negative for A. platys . These results demonstrate that L. infantum is able to penetrate into the brain parenchyma, either alone or in association to other zoonotic pathogens. In addition, qPCR could be considered for adequate evaluation of Leishmania in the brain tissue of dogs with neurological signs that have died.

Diarrheagenic Escherichia coli pathotypes investigation revealed atypical enteropathogenic E. coli as putative emerging diarrheal agents in children living in Botucatu, São Paulo State, Brazil.

The aim of the present study was to investigate the prevalence of Diarrheagenic Escherichia coli (DEC) pathotypes, a leading cause of diarrhea worldwide, among diarrheal and healthy children, up to 5 years of age, living in the city of Botucatu, São Paulo, Brazil. DEC, investigated by PCR detection of virulence factor-encoding genes associated with the distinct pathotypes, was isolated from 18.0% of the patients, and 19.0% of the controls, with enteroaggregative E. coli (EAEC), the most frequent pathotype, being detected in equal proportion between patients and controls (10.0%). Among the enteropathogenic E. coli (EPEC) isolates, only one isolate was able to produce the localized adherence pattern to HeLa cells, being thus the only typical EPEC identified. All the remaining EPEC were classified as atypical (aEPEC), and detected in 8.0% and 8.5% of the patients and controls, respectively. Regarding the serotypes, 26.5% of the analyzed EPEC isolates belonged to classical EPEC-serogroups, and the only two STEC found were serotyped as O26:H11 (patient) and O119:H7 (control). Antimicrobial susceptibility tests revealed that 43.6%, 29.5% and 2.6% of the DEC isolates were resistant to ampicillin, cotrimoxazole and gentamicin, respectively. Our data indicate that EAEC remains prevalent among children living in Botucatu, and revealed atypical EPEC as emerging putative diarrheal agents in this geographical region.

Clonal relatedness and resistance patterns of Salmonella Corvallis from poultry carcasses in a Brazilian slaughterhouse.

INTRODUCTION: Salmonella is a major cause of foodborne disease, and poultry products are important contributors to the transmission of this zoonotic pathogen. Although considered to be rare in most countries, Salmonella Corvallis has been reported in specific geographic areas isolated from both human and non-human sources. The aim of this study was to report the occurrence, the antimicrobial resistance profiles including the extended-spectrum beta-lactamase (ESBL) production, and the clonal relatedness of S. Corvallis strains. METHODOLOGY: A total of 132 fragments of poultry carcasses from a slaughterhouse in São Paulo State, Brazil, were collected at different stages of the manufacturing process (post-bleeding, post-plucking, and post-chilling) and analyzed for the presence of Salmonella. Antimicrobial resistance was determined by disc diffusion method and Etest. Clonal relatedness was determined by pulsed-field gel electrophoresis (PFGE). RESULTS: Among the 272 Salmonella strains recovered, fourteen were S. Corvallis. Ten (71.4%) showed ESBL production and resistance to at least three antimicrobial agents. Nalidixic acid resistance and reduced ciprofloxacin susceptibility was verified in four (28.6%) strains. PFGE analyses showed that all the S. Corvallis strains belonged to the same pulsotype. CONCLUSION: This study identified genetically related S. Corvallis strains exhibiting ESBL production and reduced susceptibility to quinolone. The results suggest the need to improve the sanitary conditions in the slaughterhouse. Moreover, from a public health perspective, continuous surveillance on Salmonella is needed to control the dissemination of this important zoonotic pathogen and its resistance determinants.

Frequency, serotyping and antimicrobial resistance pattern of Salmonella from feces and lymph nodes of pigs / Isolamento, sorotipagem e padrões de resistência a antimicrobianos de Salmonella em fezes e linfonodos de suínos

Salmonellosis is a foodborne disease caused by bacteria of the genus Salmonella, being pigs and pork-products potentially important for its occurrence. In recent decades, some serovars of Salmonella have shown increase of resistance to conventional antimicrobials used in human and animal therapy, with serious risks for public health. The aim of this study was to evaluate feces (n=50), mediastinal (n=50), mesenteric (n=50) and mandibular (n=50) lymph nodes obtained from slaughter houses for Salmonella spp. Positive samples were serotyped and subjected to an in vitro antimicrobial susceptibility test, including the extended-spectrum beta-lactamase (ESBL) production. Salmonella species were identified in 10% (20/200) of total samples. From these, 20% (10/50) were identified in the submandibular lymph nodes, 18% (9/50) in the mesenteric lymph nodes, 2% (1/50) in feces and 0% (0/50) in the mediastinal lymph nodes. The serotypes found were Salonella Typhimurium (55%), S. enterica subsp. enterica 4,5,12: i: - (35%), S. Brandenburg and S. Derby with 5% (5% each). All strains showed resistance to at least one antimicrobial; 90% were resistant to four or more antimicrobials, and 15% were multidrug-resistant. Resistance to ciprofloxacin, tetracycline and nalidixic acid was particularly prevalent amongst the tested serovars. Here, we highlighted the impact of pigs in the epidemiological chain of salmonellosis in domestic animals and humans, as well as the high antimicrobial resistance rates of Salmonella strains, reinforcing the necessity for responsible use of antimicrobials for animals as an emergent One Health issue, and to keep these drugs for human therapy approaches.(AU)

Nas últimas décadas, o aumento de cepas circulante de Salmonella concomitantemente a resistência microbiana tem despertado a preocupação dos órgãos de Saúde Pública. Deste modo, o objetivo do presente trabalho foi pesquisar a presença de Salmonella a partir de fezes (n=50), linfonodos mediastinos (n=50), mesentéricos (n=50) e submandibular (n=50) oriundos de um abatedouro suíno. As cepas isoladas foram sorotipadas e testadas quanto a resistência antimicrobiana. A presença de Salmonella isolada foram em 10% (20/200) do total de amostras, sendo 20% dos linfonodos submandibulares, 18% dos linfonodos mesentéricos e 2% das fezes. Os sorotipos encontrados foram S. Typhimurium (55%), S. enterica subsp. enterica 4,5,12: i: - (35%), S. Brandenburg (5%) e S. Derby (5%). Todas a cepas apresentaram resistência a pelo menos um antimicrobiano testado, sendo 90% resistente pelo menos quatro antimicrobianos. Destes, 15% foram classificadas como multidrogas resistentes. Os antimicrobianos mais resistentes entre os sorovares isolados foram a ciprofloxacina, tetraciclina e o ácido nalidixico. A presença de cepas de Salmonella resistente a antimicrobianos na espécie suína tem gerado um grande impacto epidemiológico entre homem e animal, reforçando cada vez mais a necessidade do uso adequado de drogas principalmente relacionado com o tema "One Health".(AU)