Genomic Characterization and Genetic Profiles of Salmonella Gallinarum Strains Isolated from Layers with Fowl Typhoid in Colombia.

Salmonella Gallinarum (SG) is the causative agent of fowl typhoid (FT), a disease that is harmful to the poultry industry. Despite sanitation and prophylactic measures, this pathogen is associated with frequent disease outbreaks in developing countries, causing high morbidity and mortality. We characterized the complete genome sequence of Colombian SG strains and then performed a comparative genome analysis with other SG strains found in different regions worldwide. Eight field strains of SG plus a 9R-derived vaccine were subjected to whole-genome sequencing (WGS) and bioinformatics analysis, and the results were used for subsequent molecular typing; virulome, resistome, and mobilome characterization; and a comparative genome study. We identified 26 chromosome-located resistance genes that mostly encode efflux pumps, and point mutations were found in gyrase genes (gyrA and gyrB), with the gyrB mutation S464T frequently found in the Colombian strains. Moreover, we detected 135 virulence genes, mainly in 15 different Salmonella pathogenicity islands (SPIs). We generated an SPI profile for SG, including C63PI, CS54, ssaD, SPI-1, SPI-2, SPI-3, SPI-4, SPI-5, SPI-6, SPI-9, SPI-10, SPI-11, SPI-12, SPI-13, and SPI-14. Regarding mobile genetic elements, we found the plasmids Col(pHAD28) and IncFII(S) in most of the strains and 13 different prophage sequences, indicating a frequently obtained profile that included the complete phage Gifsy_2 and incomplete phage sequences resembling Escher_500465_2, Shigel_SfIV, Entero_mEp237, and Salmon_SJ46. This study presents, for the first time, the genomic content of Colombian SG strains and a profile of the genetic elements frequently found in SG, which can be further studied to clarify the pathogenicity and evolutionary characteristics of this serotype.

Cellular immune response after vaccination with Salmonella Gallinarum 9R in laying hens and addition of aflatoxin and absorbent in the feed.

Salmonella Gallinarum greatly impacts commercial flocks and vaccination with S. Gallinarum 9R (SG9R) is one of the most effective control strategies in some countries. However, mycotoxins can affect immunization success. Herein, we measured the cellular immune response in SG9R-vaccinated hens, quantified the impact of aflatoxins on the immune response, and determined whether the anti-mycotoxin additive (adsorbent) influences immunity after vaccination. One-day-old chicks of commercial laying hens were raised until 49 days of age and were assigned to six groups. T1 (control group): control diet (no detectable concentration of aflatoxin), no vaccine or adsorbent. T2: vaccine SG-9R at day 28, aflatoxins 2.5 ppm from day 1 to day 49, and adsorbent 2.5 Kg/ton. T3: control diet and vaccine. T4: aflatoxins and vaccine. T5: control diet and aflatoxins. T6: aflatoxins and adsorbent. Body weights were evaluated on days 1, 31, and 41. Cellular immune response was evaluated by flow cytometry at 31, 41, and 49 days of age. T lymphocytes, B lymphocytes, monocytes, phagocytic monocytes and heterophils were evaluated. Aflatoxins suppressed peripheral and mucosal helper T lymphocytes, and mucosal cytotoxic T lymphocytes in vaccinated birds (T2 and T4). However, inclusion of the adsorbent in the feed of vaccinated birds neutralized the effects of aflatoxin (T6). The concentration of immune cells may show differences after SG9R vaccination, particularly an increase in the monocyte concentration. The SG9R vaccine reduced the concentration of activated cytotoxic T lymphocytes, making this marker a good parameter to analyze before and three weeks after immunization.

Three Months of Composting Are Enough to Eliminate the Fowl Typhoid Bacteria

The composting technique has been increasingly highlighted in poultry production units, as an efficient and low-cost solution for the destination of carcasses. The process is based on the accelerated decomposition of organic material under high temperatures, associated with eliminating pathogenic microorganisms. This study aims to evaluate the effectiveness and the time necessary for the elimination of Salmonella Gallinarum in carcasses of poultry submitted to the composting process. The composting was carried out following the models used in the field, and microbiological analysis was performed in five different periods: 45, 90, 120, 150 and 180-days after closing the composter. After 90 days of experiment and in the subsequent analysis, the elimination of the bacteria in 100% of the samples was verified, validating the composting process as an effective method for eliminating S. Gallinarum in poultry carcasses, when respecting the period necessary for the elimination of the bacteria and the good quality of the structure adopted for the process.(AU)

Emergence, Dissemination and Antimicrobial Resistance of the Main Poultry-Associated Salmonella Serovars in Brazil.

Salmonella infects poultry, and it is also a human foodborne pathogen. This bacterial genus is classified into several serovars/lineages, some of them showing high antimicrobial resistance (AMR). The ease of Salmonella transmission in farms, slaughterhouses, and eggs industries has made controlling it a real challenge in the poultry-production chains. This review describes the emergence, dissemination, and AMR of the main Salmonella serovars and lineages detected in Brazilian poultry. It is reported that few serovars emerged and have been more widely disseminated in breeders, broilers, and layers in the last 70 years. Salmonella Gallinarum was the first to spread on the farms, remaining as a concerning poultry pathogen. Salmonella Typhimurium and Enteritidis were also largely detected in poultry and foods (eggs, chicken, turkey), being associated with several human foodborne outbreaks. Salmonella Heidelberg and Minnesota have been more widely spread in recent years, resulting in frequent chicken/turkey meat contamination. A few more serovars (Infantis, Newport, Hadar, Senftenberg, Schwarzengrund, and Mbandaka, among others) were also detected, but less frequently and usually in specific poultry-production regions. AMR has been identified in most isolates, highlighting multi-drug resistance in specific poultry lineages from the serovars Typhimurium, Heidelberg, and Minnesota. Epidemiological studies are necessary to trace and control this pathogen in Brazilian commercial poultry production chains.

Virulence genes and sanitizers resistance in Salmonella isolates from eggs in southern Brazil.

Salmonella spp. causes foodborne diseases related to the consumption of contaminated foods, especially poultry products. This study aimed to investigate the occurrence of Salmonella spp. serovars in raw eggs from supermarkets and street food markets in southern Brazil, to analyze virulence genes, resistance profiling to antimicrobials and sanitizers, and to determine the susceptibility of the isolates to Butia odorata extract. Among 160 samples analyzed, just two (1.25%) were positive for Salmonella spp.. One positive sample was from egg yolk (S. enterica serovar Gallinarum, isolate S28), and another one was from eggshell (S. enterica serovar Panama, isolate S37). Regarding the virulence genes, the isolate S37 harbored all the genes evaluated (hilA, invA, spvC, sefA, and pefA), while the isolate S28 did not harbor the pefA gene. The isolate S28 was resistant to tobramycin, azithromycin, and trimethoprim, while the isolate S37 showed resistance profile just to nalidixic acid. However, none of the resistance genes evaluated were identified. Both isolates showed resistance to benzalkonium chloride, chlorhexidine digluconate, sodium hypochlorite, and peracetic acid, presenting high MIC values for these sanitizers. In contrast, B. odorata extract showed antimicrobial activity against the isolates S28 and S37, however, more studies are needed to prove its potential as a natural antimicrobial compound.

Phylogeny and Life Cycles of the Archiacanthocephala with a Note on the Validity of Mediorhynchus gallinarum.

PURPOSE: The molecular profile of specimens of Mediorhynchus gallinarum (Bhalero, 1937) collected from chickens, Gallus gallus L. in Indonesia was analysed. The aim of this study was to assess the phylogenetic position of species of Mediorhynchus within the order Giganthorhynchida. METHODS: We used one mitochondrial gene (cytochrome oxidase 1) and one nuclear gene (18S ribosomal RNA) to infer phylogenetic relationships of class Archiacanthocephala. RESULTS: The COI and 18S rDNA genes sequences showed that M. gallinarum had low genetic variation and that this species is sister to Mediorhynchus africanus Amin, Evans, Heckmann, El-Naggar, 2013. The phylogenetic relationships of the Class Archiacanthocephala showed that it is not resolved but, however, were mostly congruent using both genes. A review of host-parasite life cycles and geographic distributions of Archiacanthocephala indicates that mainly small mammals and birds are definitive hosts, while termites, cockroaches, and millipedes are intermediate hosts. CONCLUSIONS: While the intermediate hosts have wide geographic distributions, the narrow distribution of the definitive hosts limit the access of archiacanthocephalans to a wider range of prospective hosts. Additional analyses, to increase taxonomic and character sampling will improve the development of a robust phylogeny and provide more stable classification. The results presented here contribute to better understanding of the ecological and evolutionary relationships that allow the host-parasite co-existence within the class Archiacanthocephala.

Influencia de Salmonella pullorum y S. gallinarum en la producción avícola y la salud pública / Influence of Salmonella pullorum and S. gallinarum on poultry production and public health

La calidad de los alimentos que consumimos se ha convertido en uno de los principales problemas de salud pública a nivel mundial, ya que son la puerta de entrada de patógenos y vectores para la trasmisión de diversas enfermedades. Se estimó que el 17,9% de las enfermedades trasmitidas por el consumo de alimentos, está relacionada con aves de corral, y el 19% de estas enfermedades, están asociadas a la contaminación por Salmonella entérica. La Salmonelosis es una enfermedad invasiva que afecta en gran medida a las poblaciones altamente vulnerables (niños, ancianos e inmunocomprometidos), causando la necesidad de hospitalización y en ocasiones la muerte. A nivel mundial se estima que anualmente hay más de 94 millones de personas afectadas por gastroenteritis causada por el consumo de aves contaminadas con Salmonella, así como más de 155.000 fallecidos. Sin embargo, los orígenes de esta cepa: Salmonella entérica y otras de mayor alcance patógeno están influenciadas muy de cerca por el control de dos cepas con poca acción en la población humana: la S. polloroum y la S. gallinarum. La casi desaparición de estos dos serovares impulsó la colonización de cepas más resistente a los antibióticos y más perjudiciales para los seres humanos(AU)

The quality of the food we consume has become one of the main public health problems worldwide, since it is the gateway for pathogens and vectors for the transmission of various diseases. It was estimated that 17.9% of diseases transmitted by food consumption are related to poultry, and 19% of these diseases are associated with contamination by Salmonella enterica. Salmonellosis is an invasive disease that greatly affects highly vulnerable populations (children, the elderly and immunocompromised), causing the need for hospitalization and sometimes death. Worldwide, it is estimated that annually there are more than 94 million people affected by gastroenteritis caused by the intake of poultry contaminated with Salmonella, as well as more than 155,000 deaths. However, the origins of this strain: Salmonella enterica and others with a greater pathogenic scope are closely influenced by the control of two strains with little action in the human population: S. polloroum and S. gallinarum. The near disappearance of these two serovars prompted the colonization of strains more resistant to antibiotics and more harmful to humans(AU)

Pathomorphological and molecular investigations in naturally infected Chukar partridges (Alectoris Chukar) with Histomonas meleagridis and Tetratrichomonas gallinarum / Investigações patomorfológicas e moleculares em perdizes Chukar (Alectoris Chukar) naturalmente infectadas com Histomonas meleagridis e Tetratrichomonas gallinarum

Histomonas meleagridis and Tetratrichomonas gallinarum are two protozoans responsible for mortality associated with typhlohepatitis in poultry. In this study, the etiology of high mortality in Chukar partridges suspected of infection with these agents was investigated pathologically and molecularly. Twelve healthy partridges during the laying period and 30 partridges that died due to disease and were included in the study. In blood analysis, increased levels of WBC, NEU, LYM, MONO, EO and BASO suggesting bacterial and/or parasitic infection; decreased levels of HGB, MCH and MCHC, which are markers of anemia; and increased AST and LDH levels, which are important for liver degenerations. In the liver, which is one of the most pathologically affected organs, multifocal necrosis foci that sometimes merge with each other and spread to large areas, and severe fibrino-necrotic typhlitis were detected. There was amyloid deposition in the space of Disse and vascular sinuses in the liver. PAS positive protozoal agents were observed in and around the lesioned areas. By PCR analyzes using specific primers, 11 of the samples were positive for H. meleagridis only, whereas 5 were positive for T. gallinarum only; 14 samples tested positive for both agents. Sequence analysis showed 100% identity between all samples resulting in positive PCR. In addition, Escherichia coli was produced in microbiological culture (27 of 30). When all the results were evaluated together, it was concluded that H. meleagridis and T. gallinarum and secondary E. coli may cause high mortality in partridges under lay stress.

Histomonas meleagridis e Tetratrichomonas gallinarum são dois protozoários responsáveis pela mortalidade associada à tiflohepatite em aves. Neste estudo, a etiologia da alta mortalidade em perdizes Chukar com suspeita de infecção por esses agentes foi investigada patologicamente e molecularmente. Foram incluídas no estudo 30 perdizes que morreram devido à doença e 12 perdizes saudáveis durante o período de postura. Na análise sanguínea, níveis aumentados de WBC, NEU, LYM, MONO, EO e BASO sugerindo infecção bacteriana e/ou parasitária; diminuição dos níveis de HGB, MCH e MCHC, que são marcadores de anemia; e aumento dos níveis de AST e LDH, que são importantes para as degenerações hepáticas. No fígado, que é um dos órgãos patologicamente mais acometidos, foram detectados focos de necrose multifocais que às vezes se fundem e se espalham para grandes áreas, e tiflite fibrino-necrótica grave no ceco. Houve deposição de amiloide no espaço de Disse e seios vasculares no fígado. Agentes protozoários PAS positivos foram observados dentro e ao redor das áreas lesionadas. Pelas análises de PCR com primers específicos, 11 das amostras foram positivas apenas para H. meleagridis, enquanto 5 foram positivas apenas para T. gallinarum; 14 amostras testaram positivo para ambos os agentes. A análise de sequência mostrou 100% de identidade entre todas as amostras resultando em PCR positivo. Além disso, Escherichia coli foi produzida em cultura microbiológica. Quando todos os resultados foram avaliados em conjunto, concluiu-se que H. meleagridis e T. gallinarum e E. coli secundária podem causar alta mortalidade em perdizes sob estresse de postura.

Heat stress impairs egg production in commercial laying hens infected by fowl typhoid.

Salmonella Gallinarum (SG) is an avian-restricted pathogen that causes fowl typhoid in poultry. Although it has been reported frequently over many decades in poultry flocks worldwide, the microorganism is more commonly associated with poultry in developing countries, particularly those with high ambient temperatures, where the acute form of the disease results in considerable economic losses. A more detailed investigation of environmental factors that affect the course of disease may assist in identifying effective prevention and control measures. Heat stress is known to impair the immunological response to a variety of pathogens and clearly may be an important contributory factor in the prevalence of disease in countries with warm or hot climates. Thus, the objective of the present study was to evaluate the effects of heat stress on chickens infected with SG. For this, light and semi-heavy commercial laying hens were distributed randomly within four groups as follows: infected and non-infected groups in rooms held at ambient temperature, and infected and non-infected groups under heat stress. Clinical signs, egg production, and mortality were recorded daily. Bacteriological counts in liver and spleen samples were estimated at 2, 5, 7, and 14 days post-infection. The results showed that both SG infection and heat stress had similar effects on egg production and a synergistic effect of the two stressors was observed. The data show an interaction between disease and heat stress which could point towards environmental and biosecurity approaches to resolving the possible 30% fall in production observed in such countries.

Effect of doses and administration routes of 9R vaccine on protection of Japanese quails against experimental infection with Salmonella Gallinarum / Efeito das doses e vias de administração da vacina 9R na proteção de codornas japonesas contra infeccção experimental com Salmonella Gallinarum

Coturniculture has increased significantly in the last decades. There are several pathogens that can affect these birds. Among the diseases, fowl typhoid stands out as a disease with a potentially great impact to the poultry industry. The objective of this the study was to evaluate the effect of doses and administration routes of live 9R vaccine on protection of Japanese quails against experimental infection with Salmonella Gallinarum (SG). Two hundred and fifty birds were used, divided into five groups: G1, oral vaccination with one dose; G2, oral vaccination with 2 doses; G3, subcutaneous vaccination with one dose; G4, subcutaneous vaccination with two doses and G5 not vaccinated. All birds from all five groups were challenged with SG at an age of 45 days. SG was quantified in the periods of one, four, seven and twelve days after the challenge. The presence of clinical signs and macroscopic lesions of the disease were observed. The groups vaccinated by subcutaneous route had a higher egg production and lower mortality rate. Birds receiving a dose of the vaccine by subcutaneous route also showed lower amount of SG in the liver and spleen seven days after the challenge.(AU)

A coturnicultura tem aumentado significativamente nas últimas décadas. Existem vários patógenos que podem afetar essas aves. Entre as doenças, o tifo aviário se destaca como uma doença de grande impacto para a indústria avícola. O objetivo deste estudo foi avaliar o efeito de doses e vias de administração da vacina viva 9R na proteção de codornas japonesas contra infecção experimental por Salmonella Gallinarum (SG). Foram utilizadas duzentos e cinquenta aves, divididas em cinco grupos: G1, vacinação oral com uma dose; G2, vacinação oral com 2 doses; G3, vacinação subcutânea com uma dose; G4, vacinação subcutânea com duas doses e G5 não vacinado. Todas as aves dos cinco grupos foram desafiadas com SG aos 45 dias de idade. A SG foi quantificada nos períodos de um, quatro, sete e doze dias após o desafio. Foi observada a presença de sinais clínicos e lesões macroscópicas da doença. Os grupos vacinados por via subcutânea apresentaram maior produção de ovos e menor taxa de mortalidade. Aves recebendo uma dose da vacina por via subcutânea também apresentaram menor quantidade de SG no fígado e baço sete dias após o desafio.(AU)

Effect of doses and administration routes of 9R vaccine on protection of Japanese quails against experimental infection with Salmonella Gallinarum / Efeito das doses e vias de administração da vacina 9R na proteção de codornas japonesas contra infeccção experimental com Salmonella Gallinarum

Coturniculture has increased significantly in the last decades. There are several pathogens that can affect these birds. Among the diseases, fowl typhoid stands out as a disease with a potentially great impact to the poultry industry. The objective of this the study was to evaluate the effect of doses and administration routes of live 9R vaccine on protection of Japanese quails against experimental infection with Salmonella Gallinarum (SG). Two hundred and fifty birds were used, divided into five groups: G1, oral vaccination with one dose; G2, oral vaccination with 2 doses; G3, subcutaneous vaccination with one dose; G4, subcutaneous vaccination with two doses and G5 not vaccinated. All birds from all five groups were challenged with SG at an age of 45 days. SG was quantified in the periods of one, four, seven and twelve days after the challenge. The presence of clinical signs and macroscopic lesions of the disease were observed. The groups vaccinated by subcutaneous route had a higher egg production and lower mortality rate. Birds receiving a dose of the vaccine by subcutaneous route also showed lower amount of SG in the liver and spleen seven days after the challenge.(AU)

A coturnicultura tem aumentado significativamente nas últimas décadas. Existem vários patógenos que podem afetar essas aves. Entre as doenças, o tifo aviário se destaca como uma doença de grande impacto para a indústria avícola. O objetivo deste estudo foi avaliar o efeito de doses e vias de administração da vacina viva 9R na proteção de codornas japonesas contra infecção experimental por Salmonella Gallinarum (SG). Foram utilizadas duzentos e cinquenta aves, divididas em cinco grupos: G1, vacinação oral com uma dose; G2, vacinação oral com 2 doses; G3, vacinação subcutânea com uma dose; G4, vacinação subcutânea com duas doses e G5 não vacinado. Todas as aves dos cinco grupos foram desafiadas com SG aos 45 dias de idade. A SG foi quantificada nos períodos de um, quatro, sete e doze dias após o desafio. Foi observada a presença de sinais clínicos e lesões macroscópicas da doença. Os grupos vacinados por via subcutânea apresentaram maior produção de ovos e menor taxa de mortalidade. Aves recebendo uma dose da vacina por via subcutânea também apresentaram menor quantidade de SG no fígado e baço sete dias após o desafio.(AU)

A comparative survey between non-systemic Salmonella spp. (paratyphoid group) and systemic Salmonella Pullorum and S. Gallinarum with a focus on virulence genes / Uma investigação comparativa entre Salmonella spp. não-sistêmicas (grupo paratifoide) e sistêmicas Salmonella Pullorum e S. Gallinarum com enfoque nos genes de virulência

A comparative survey between non-systemic (paratyphoid Salmonellae) and systemic (S. Pullorum and S. Gallinarum) Salmonella strains was performed to produce a virulence gene profile for differentiation among the groups. The following virulence genes were evaluated: invA, spvC, sefC, pefA, fimY, sopB, sopE1, stn and avrA. There are substantial differences among paratyphoid Salmonellae, S. Pullorum, and S. Gallinarum regarding the genes sefC, spvC, sopE1 and avrA. A higher frequency of sefC, spvC, sopE1 and avrA genes were detected in S. Gallinarum and S. Pullorum when compared with strains from the paratyphoid group of Salmonella. These results may be useful for differentiating among different groups and serotypes.(AU)

Uma investigação comparativa entre amostras de Salmonella não-sistêmicas (grupo paratifoide) e sistêmicas (S. Pullorum and S. Gallinarum) foi desenvolvida para produzir um perfil de genes de virulência para diferenciação entre os grupos. Os seguintes genes de virulência foram avaliados invA, spvC, sefC, pefA, fimY, sopB, sopE1, stn e avrA. Detectou-se uma diferença substancial entre Salmonella do grupo paratifoide, S. Pullorum e S. Gallinarum considerando os genes sefC, spvC, sopE1 e avrA. Os genes sefC, spvC, sopE1 e avrA foram detectados, em maior número, em S. Gallinarum e S. Pullorum quando comparados com as amostras de Salmonella do grupo paratifoide. Estes resultados podem ser úteis para a diferenciação entre os diferentes grupos e sorotipos de Salmonella.(AU)

A comparative survey between non-systemic Salmonella spp. (paratyphoid group) and systemic Salmonella Pullorum and S. Gallinarum with a focus on virulence genes / Uma investigação comparativa entre Salmonella spp. não-sistêmicas (grupo paratifoide) e sistêmicas Salmonella Pullorum e S. Gallinarum com enfoque nos genes de virulência

A comparative survey between non-systemic (paratyphoid Salmonellae) and systemic (S. Pullorum and S. Gallinarum) Salmonella strains was performed to produce a virulence gene profile for differentiation among the groups. The following virulence genes were evaluated: invA, spvC, sefC, pefA, fimY, sopB, sopE1, stn and avrA. There are substantial differences among paratyphoid Salmonellae, S. Pullorum, and S. Gallinarum regarding the genes sefC, spvC, sopE1 and avrA. A higher frequency of sefC, spvC, sopE1 and avrA genes were detected in S. Gallinarum and S. Pullorum when compared with strains from the paratyphoid group of Salmonella. These results may be useful for differentiating among different groups and serotypes.(AU)

Uma investigação comparativa entre amostras de Salmonella não-sistêmicas (grupo paratifoide) e sistêmicas (S. Pullorum and S. Gallinarum) foi desenvolvida para produzir um perfil de genes de virulência para diferenciação entre os grupos. Os seguintes genes de virulência foram avaliados invA, spvC, sefC, pefA, fimY, sopB, sopE1, stn e avrA. Detectou-se uma diferença substancial entre Salmonella do grupo paratifoide, S. Pullorum e S. Gallinarum considerando os genes sefC, spvC, sopE1 e avrA. Os genes sefC, spvC, sopE1 e avrA foram detectados, em maior número, em S. Gallinarum e S. Pullorum quando comparados com as amostras de Salmonella do grupo paratifoide. Estes resultados podem ser úteis para a diferenciação entre os diferentes grupos e sorotipos de Salmonella.(AU)

Further investigations on the epidemiology of fowl typhoid in Brazil.

Salmonella Gallinarum (SG) causes fowl typhoid (FT), a disease responsible for economic losses to the poultry industry worldwide. FT has been considered to be under control in Brazil; nevertheless, since 2012 it has frequently been identified in poultry farming of several Brazilian states. The present study was aimed at assessing (i) the pathogenicity of a SG strain recently isolated from an FT outbreak affecting chickens of both white and brown layers; (ii) the transmission of SG through eggs and hatching; (iii) the effects of antibiotic therapy on SG persistence in poultry tissues and on its vertical transmission and (iv) the genetic profiles of strains isolated over 27 years by Pulsed Field Gel Electrophoresis. Clinical signs, mortality and gross pathologies were very marked amongst brown-egg layers. In contrast, clinical manifestation of FT and mortality were barely present amongst the white-egg layers, although bacteria could be re-isolated from their tissues up to 35 days after infection. No bacteria were re-isolated from the laid eggs, so vertical transmission was not achieved, although newly hatched uninfected chicks became infected spontaneously after hatching. Antibiotic therapy was shown to be effective at reducing mortality, but was not able to clear infection or to favour SG transmission via eggs. Our pulsed field gel electrophoresis results revealed an endemic SG clone that may have been circulating in the Brazilian poultry flocks in the south and southeast regions for more than 20 years. The results suggest that the industrial incubation of SG-contaminated eggs could be one of the factors responsible for the spread of FT in Brazil.

Antibiotic-Induced Pathobiont Dissemination Accelerates Mortality in Severe Experimental Pancreatitis.

Although antibiotic-induced dysbiosis has been demonstrated to exacerbate intestinal inflammation, it has been suggested that antibiotic prophylaxis may be beneficial in certain clinical conditions such as acute pancreatitis (AP). However, whether broad-spectrum antibiotics, such as meropenem, influence the dissemination of multidrug-resistant (MDR) bacteria during severe AP has not been addressed. In the currently study, a mouse model of obstructive severe AP was employed to investigate the effects of pretreatment with meropenem on bacteria spreading and disease outcome. As expected, animals subjected to biliopancreatic duct obstruction developed severe AP. Surprisingly, pretreatment with meropenem accelerated the mortality of AP mice (survival median of 2 days) when compared to saline-pretreated AP mice (survival median of 7 days). Early mortality was associated with the translocation of MDR strains, mainly Enterococcus gallinarum into the blood stream. Induction of AP in mice with guts that were enriched with E. gallinarum recapitulated the increased mortality rate observed in the meropenem-pretreated AP mice. Furthermore, naïve mice challenged with a mouse or a clinical strain of E. gallinarum succumbed to infection through a mechanism involving toll-like receptor-2. These results confirm that broad-spectrum antibiotics may lead to indirect detrimental effects during inflammatory disease and reveal an intestinal pathobiont that is associated with the meropenem pretreatment during obstructive AP in mice.

Experimental infection of chickens by a flagellated motile strain of Salmonella enterica serovar Gallinarum biovar Gallinarum.

Salmonella enterica subsp. enterica serovar Gallinarum biovar Gallinarum (SG) causes fowl typhoid (FT), a septicaemic disease which can result in high mortality in poultry flocks. The absence of flagella in SG is thought to favour systemic invasion, since bacterial recognition via Toll-like receptor (TLR)-5 does not take place during the early stages of FT. In the present study, chicks susceptible to FT were inoculated with a wild type SG (SG) or its flagellated motile derivative (SG Fla(+)). In experiment 1, mortality and clinical signs were assessed, whereas in experiment 2, gross pathology, histopathology, systemic invasion and immune responses were evaluated. SG Fla(+) infection resulted in later development of clinical signs, lower mortality, lower bacterial numbers in the liver and spleen, and less severe pathological changes compared to SG. The CD8(+) T lymphocyte population was higher in the livers of chicks infected with SG at 4 days post-inoculation (dpi). Chicks infected with SG had increased expression of interleukin (IL)-6 mRNA in the caecal tonsil at 1 dpi and increased expression of IL-18 mRNA in the spleen at 4 dpi. In contrast, the CD4(+) T lymphocyte population was higher at 6 dpi in the livers of birds infected with SG Fla(+). Therefore, flagella appeared to modulate the chicken immune response towards a CD4(+) T profile, resulting in more efficient bacterial clearance from systemic sites and milder infection.

Influence of heat-labile serum components in the presence of OmpA on the outer membrane of Salmonella gallinarum.

Salmonella gallinarum is the causative agent of fowl typhoid. Being a Gram-negative bacteria, its outer membrane proteins (OMP) can be regulated by different microenvironments. S. gallinarum was cultured under the following conditions: nutrient broth (NB), NB supplemented with serum from specific pathogen-free birds (NBS) and NB with serum incubated at 56 °C prior to incubation with the bacteria (NBSD); OMP were subsequently extracted. Several changes were observed in the apparent expression of OMP, mainly a decrease in an OMP with a size of 30 kDa, approximately, under the NBS condition. In contrast, the same event was not observed in NB and NBSD when using one- and two-dimensional polyacrylamide gels (SDS-PAGE). Using the OMP with a size of 30 kDa, approximately, as antigen in indirect ELISA, we were able to differentiate serum from healthy and vaccinated birds, as well as birds infected with S. gallinarum and S. enteritidis. The amino-terminal of this protein was sequenced, showing 100 % identity with OmpA of S. typhimurium. Subsequently, we designed primers to amplify the gene by PCR. The partial sequence of the amplified gene showed 100 % identity with OmpA of S. gallinarum. (1) Heat-labile serum components influence the presence of OmpA in the OM of S. gallinarum; (2) by the way of ELISA, OmpA allows to specifically differentiate healthy from diseased birds.

Influence of gastrointestinal parasitism on biochemical variables in blood of laying hens / Influencia del parasitismo gastrointestinal en las variables bioquímicas en la sangre de las gallinas ponedoras

Objective. This study describes the influence of endoparasites and diet on biochemical variables in sera of brown laying hens. Materials and methods. Biochemical parameters (seric levels of cholesterol, triglycerides, total protein, uric acid, albumin, and alanine aminotransferase activity) were assessed in blood samples of poultry. Three populations of laying hens of different properties (n=20 each) represented our experimental design, from which blood (serum) and feces were collected for biochemical and parasitological analyzes, respectively. Results. From 60 feces samples evaluated 49 were positive for the presence of parasites and 11 were negative. Among the positive samples, 23 had infection with Eimeria spp and the other 26 samples had mixed parasitism with Eimeria spp and Heterakis gallinarum, which influenced (increasing) the levels of total protein and globulin. However, when parasites were analyzed separately, it was observed that the infection by Eimeria spp affected parameters such as cholesterol (which increased, p=0.001) and triglycerides, showing lower results than when the hen was parasitized by Eimeria spp. (p=0.01). Significant (p<0.05) difference was observed in all biochemical variables when the three diets were compared. Conclusions. Our results allowed concluding that the parasitic infection and diet in laying hens influenced the results of serum biochemical parameters evaluated. The main conclusion we found that parasitism caused an increase in total protein and globulin (ie immune response), and there was a negative correlation between parasite load and albumin, uric acid and ALT.

Objetivo. Este estudio describe la influencia de la dieta sobre los endoparásitos y variables bioquímicas en el suero de las gallinas ponedoras marrones. Materiales y métodos. Los parámetros bioquímicos (niveles séricos de colesterol, triglicéridos, proteínas totales, ácido úrico, albúmina, y la actividad de la alanina aminotransferasa) se evaluaron en muestras de sangre de las aves de corral. Tres poblaciones de gallinas ponedoras de distintas propiedades (n=20 cada uno) representan nuestro diseño experimental, de la que se recogieron la sangre (suero) y las heces de bioquímica y análisis parasitológico, respectivamente. Resultados. De 60 muestras de heces evaluadas, 49 fueron positivos para la presencia de parásitos y 11 fueron negativos. Entre las muestras positivas, 23 tenían infección con Eimeria spp y las otras 26 muestras tenían parasitismo mezclado con Eimeria spp y Heterakis gallinarum, que influyó (aumentando) los niveles de proteína total y globulina. Sin embargo, cuando se analizaron por separado los parásitos, se observó que la infección por Eimeria spp afectó parámetros tales como el colesterol (el cual se incrementó p=0.001) y los triglicéridos, que mostraron resultados más bajos que cuando las gallinas fueron parasitadas por Eimeria spp. (p=0.01). Se observó diferencia (p<0.05) en todas las variables bioquímicas, cuando se compararon las tres dietas. Conclusiones. Nuestros resultados permitieron concluir que la infección parasitaria y la dieta de las gallinas ponedoras influyeron en los resultados de los parámetros bioquímicos séricos evaluados. La principal conclusión que se encontró es que el parasitismo causó un aumento de la proteína total y la globulina (es decir, la respuesta inmune), y hubo una correlación negativa entre la carga de parásitos y albúmina, ácido úrico y ALT.

The effects of managerial systems on helminth infection in freerange chickens from northern Paraná, Brazil / Os efeitos do sistema de manejo na infecção por helmintos em galinhas caipiras do norte do Paraná, Brasil

The effects of managerial systems on the occurrence of gastrointestinal helminths in Free-Range Chickens (FRCs) from northern Paraná, Brazil were investigated. The most predominant (23.3%; 61/262) cestode observed was Raillietina cesticillus; Heterakis gallinarum (71.4%; 187/262) and Ascaridia galli (45%; 118/262) were the predominant nematodes; Postharmostomum commutatum was the only trematode observed in 2.7% (7/262) of FRCs. The most elevated parasitic burdens were associated with Heterakis gallinarum, Ascaridia galli, and Raillietina cesticillus. Significant (p ? 0.05) associations were observed when the effects of the types of bedding, soil type, and fence restriction of FRCs were considered relative to the possibility of helminthiasis. The type of bedding, the length of the sanitary break, and the presence of shading significantly (p ? 0.05) influenced the possibility of FRCs being infected by H. gallinarum. Most parameters evaluated were significantly associated with infection of FRCs by A. galli. These findings suggest that FRCs from northern Paraná are infected by a wide-range of gastrointestinal helminths, but more frequently by R. cesticillus, H. gallinarum, and A. galli. Moreover, the type of floor bedding, the soil type, and the usage of fences in the management of FRCs is directly related to gastrointestinal helminthiasis.

Foram investigados os efeitos dos sistemas de manejo sobre a ocorrência de helmintos gastrintestinais em galinhas caipiras (GCs) do norte do Paraná, Brasil. O cestódeo predominante (23,3%; 61/262) foi Raillietina cesticillus; entre os nematódeos Heterakis gallinarum (71,4%, 187/262) e Ascaridia galli (45%, 118/262); Postharmostomum commutatum foi o único trematódeo encontrado em 2,7% (7/262) das GCs. As cargas parasitárias mais elevadas foram associadas à Heterakis gallinarum, Ascaridia galli e Raillietina cesticillus. Associações significantes (p ? 0,05) quanto às helmintíases foram observadas em relação ao tipo de cama, ao tipo de solo e à presença de restrição das GCs em áreas cercadas. O tipo de cama, o tempo do vazio sanitário e a presença de sombreamento influenciaram significativamente (p ? 0,05) quanto à infecção por H. gallinarum. A maioria dos parâmetros avaliados foram significativamente associados à infecção das CGs por A. galli. Estes resultados sugerem que GCs do norte do Paraná são infectadas por uma ampla variedade de helmintos gastrintestinais, porém mais frequentemente por R. cesticillus, H. gallinarum e A. galli. Além disso, o tipo de cama de forração, o tipo de solo e o uso de cercas no manejo das GCs são variáveis que estão diretamente relacionados à presença de helmintíases gastrintestinais.

Seroprevalence of Salmonella and Mycoplasma in commercial broilers, backyard chickens, and spent hens in the region of Triângulo Mineiro, State of Minas Gerais, Brazil

Avian salmonellosis and mycoplasmosis are infectious diseases that, in addition of causing lack of flock uniformity, represent a hazard to human health. The objective of the present study was to evaluate the seroprevalence of mycoplasmosis and salmonellosis in commercial broilers, backyard chickens, and spent hens slaughtered at a processing plant with local health inspection in Uberlândia, MG, Brazil. A total of 210 samples were randomly collected at the time of bleeding. Samples were submitted to rapid plate serum agglutination test (RSA) for the classification of Salmonella pullorum, Salmonella gallinarum, Mycoplasma gallisepticum and Mycoplasma synoviae. In order to increase result specificity, mycoplasmosis-positive samples were submitted to hemagglutination inhibition test (HI). No samples presented detectable antibodies against Salmonella pullorum or Salmonella gallinarum in the RSA test. Only Mycoplasma synoviae was detected in 14% of the backyard chickens and 0.74% in commercial broilers, whereas no antibodies were detected in spent hens. The seroprevalence rates found in the present study emphasize the need of keeping chicken flocks free from disease using effective biosafety systems.(AU)