Guilherme Paz Monteiro

Identificação sorológica e relação filogenética de Salmonella spp. de origem suína

Salmonella spp. is an important zoonotic pathogen that can spread along the production chain of swines. The objective was to evaluate the incidence of Salmonella spp. in feces of swines in termination phase in the farm, in the pre-slaughter and environmental samples, identify the serotypes and establish a phylogenetic relationship among the isolates. Three collections were done in different batches of pigs housed in the termination pen and in the same animals after transport to the slaughterhouse totaling 90 plots and 9 environmental samples. The transport does not influenced the percentage of isolation of the microorganism (p>0.05). Of the total of 99 samples, 50 (50.5%) were identified as Salmonella spp., and was identified a variety of serovars: Agona (30%), Typhimurium (26%), Minnesota (24%), Infantis (18%) and Panama (2%). Dendrograms showed homology among isolates of different serovars grouped into clusters. The similarity was independent of the local of isolation, indicating the presence of several clones. The main sources of infection were cross-contamination between animals and environment and the consumption of contaminated feed. The diversity of strains and homology among the isolates indicates a common origin, demonstrating a need for monitoring of zoonotic bacterias and the deployment of more effective control measures for Salmonella spp. in swines.

Intrinsic and Extrinsic Aspects on Campylobacter jejuni Biofilms

Biofilm represents a way of life that allows greater survival of microorganisms in hostile habitats. Campylobacter jejuni is able to form biofilms in vitro and on surfaces at several points in the poultry production chain. Genetic determinants related to their formation are expressed differently between strains and external conditions are decisive in this respect. Our approach combines phylogenetic analysis and the presence of seven specific genes linked to biofilm formation in association with traditional microbiology techniques, using Mueller Hinton and chicken juice as substrates in order to quantify, classify, determine the composition and morphology of the biomass of simple and mixed biofilms of 30 C. jejuni strains. It also evaluates the inhibition of its formation by biocides commonly used in industry and also by zinc oxide nanoparticles. Genetic analysis showed high heterogeneity with the identification of 23 pulsotypes. Despite the diversity, the presence of flaA, cadF, luxS, dnaJ, htrA, cbrA, and sodB genes in all strains shows the high potential for biofilm formation. This ability was only expressed in chicken juice, where they presented phenotype of a strong biofilm producer, with a mean count of 7.37 log CFU/mL and an ultrastructure characteristic of mature biofilm. The composition of simple and mixed biofilms was predominantly composed by proteins. The exceptions were found in mixed biofilms with Pseudomonas aeruginosa, which includes a carbohydrate-rich matrix, lower ability to sessile form in chicken juice and compact architecture of the biofilm, this aspects are intrinsic to this species. Hypochlorite, chlorhexidine, and peracetic acid were more effective in controlling viable cells of C. jejuni in biofilm, but the existence of tolerant strains indicates exposure to sublethal concentrations and development of adaptation mechanisms. This study shows that in chicken juice C. jejuni presents greater potential in producing mature biofilms.

Feed can be a source of Campylobacter jejuni infection in broilers

ABSTRACT 1. The aim was to determine the importance of a contaminated diet as a possible cause of Campylobacter jejuni infection in broilers. 2. This study evaluated the viability of C. jejuni in both starter and finisher diets and the interference from other mesophilic bacteria in this viability. 3. Starter and finisher samples of broiler diet were deliberately contaminated with 3 or 5 log CFU·g−1 of C. jejuni (NCTC 11351) and then maintained at two different storage temperatures (25°C or 37°C) for 3 or 5 d. 4. C. jejuni survived during this period and, when inoculated at 103 CFU·g−1, multiplied with greater proliferation at a storage temperature of 37°C. There was no relationship between the amount of mesophilic bacteria and C. jejuni viability. 5. This study highlights the importance of the diet in the epidemiology of C. jejuni in broilers.

Apostila ilustrada de cirurgia veterinária

This material is an illustrated textbook of surgery that has the function to offer consultation support to the learner of Veterinary Surgery, addressing the topics: Instrumentalization Surgical, Suture Materials, Surgical General Principles, Surgical Incisions of the Abdominal Wall and Sutures Used in Veterinary Medicine.

Epidemiology of Campylobacter in Farms

Chickens are recognized as natural hosts of Campylobacter and infected poultry carry a high pathogen load in their gastrointestinal tract. There are large gaps in our understanding about factors leading to colonization of Campylobacter and subsequent transmission among birds, given that the source of Campylobacter in chickens and specific mechanisms entering the flock are not fully clear yet. This chapter summarizes the epidemiology of Campylobacter in poultry flocks and considers current issues on the subject.

Campylobacter spp.: Capacity of Biofilm Formation and Other Strategies of Survival and Adaption to Remain in the Poultry Industry

By presenting the epidemiology of Campylobacter and the main challenges in its control, this chapter reviews the mechanisms used by these microorganisms to adapt and survive in the poultry industry. Despite Campylobacter’s apparent fragility to environmental conditions, this agent is flexible and can adapt its metabolism and growth levels to an industrial environment. This chapter addresses mechanisms such as genome modulation, tolerance to high and low temperatures, tolerance to oxidative and nutrition stress, quorum-sensing systems, and the capacity of biofilm formation. These abilities are discussed, with consideration of the potential of different behaviors that can explain the organism’s ability to survive and multiply in poultry, thus affecting the prevalence of Campylobacter in the final product.

Avaliação in vitro de óleos essenciais na inibição de Staphylococcus aureus e Escherichia coli

This work was carried through with the objective to evaluate the effect in vitro of essential oils in the inhibition of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. We tested the essential oils of rosemary (Rosmarinus officinalis), marjoran (Origanum marjorana L.), basil (Ocimum basilicum L.), eucalyptus (Eucalyptus citriodora), citronela (Cymbopogon nardus), grass-lemon (Cymbopogon citratus), previously extracted for the technique of drag the vapor. The oils had been submitted at 10 different dilutions (1/9, 2/8, 3/7, 4/6, 5/5, 6/4, 7/3, 8/2, 1/9, 1). The used technique was the embodiment of the samples in barren absorbent records that had been added on agar to contain the microorganisms and reading to subsequent of inhibition halos. The results had demonstrated that all the essential oils in the tested concentrations had not presented innibitory characteristics front to the Escherichia aureus coli ATCC 25922 and Staphylococcus aureus ATCC 25923.

Campylobacter em frangos no Brasil – Revisão de literatura

Campylobacter sp. is recognized worldwide as the bacterium that causes more diarrhea in humans, being reported as the most common zoonotic infection. Poultry meat and its derivatives are the most incriminated in the transmission to humans. The need for methods faster and less laborious detection has led to significant advances in research development and commercialization of diagnostic kits with high sensitivity and specificity in the world. Only with the knowledge of the different factors that influence the presence and multiplication of the microorganism, it is possible to establish preventive policies to prevent or control it. Thus, it is necessary to monitor diagnostic techniques are reproducible so safely subsidize the different actions for its control in Brazil.