RESUMO
Water is a prominent vehicle for Campylobacter spread throughout a chicken flock. The aim of this study was to evaluate the effect of organic acids administered through the drinking water, as a decontamination method, on gut microflora and the development of lesions in the gastrointestinal tracts of young broilers inoculated with 2 different doses of Campylobacter. The results revealed that most of the chickens were infected with Campylobacter at the end of the experiment. The drinking water was free of Campylobacter throughout the study. No difference of volatile fatty acid levels between treatment and control groups was observed in the crop and cecal contents. In the cecal contents, the total aerobic bacteria numbers were significantly higher in the treatment groups compared with the control groups (P < 0.01 and P < 0.04, respectively). Moreover, no damaged epithelial cells were observed in the chicken gut due to consumption of acidified drinking water. Acidified drinking water could therefore play a crucial role in a biosecurity strategy of preventing Campylobacter spread via drinking water in broiler flocks.
Assuntos
Infecções por Campylobacter/veterinária , Galinhas , Sistema Digestório/citologia , Sistema Digestório/microbiologia , Ácidos Graxos Voláteis/biossíntese , Água/química , Animais , Peso Corporal , Infecções por Campylobacter/microbiologia , Ceco/química , Ceco/citologia , Contagem de Colônia Microbiana , Papo das Aves/química , Papo das Aves/citologia , Células Epiteliais/citologia , Esôfago/citologia , Ácidos Graxos Voláteis/análise , Concentração de Íons de Hidrogênio , Intestino Delgado/citologiaRESUMO
The objective of this study was to determine whether host, compartment, or environmental specific factors play an important role in the establishment of the intestinal microflora in broiler chickens during growth. This objective was addressed using a 16S rDNA approach. PCR-amplicons from the V6 to V8 regions of the 16S rDNA of intestinal samples were separated by denaturing gradient gel electrophoresis (DGGE). The number of bands in all intestinal compartments increased when broilers grew older, indicating that the dominant bacterial community becomes more complex when chickens age. Each chicken had a unique banding pattern for all locations in the intestinal tract, irrespective of the age of chickens. This suggests that host-related factors affect the establishment of the dominant bacterial community. Banding patterns of intestinal compartments within one chicken were different from each other for broilers older than 4 days, except for both ceca which were highly similar. In 4-day-old broilers, banding patterns from crop, duodenum, and ileum were very similar. We conclude that (unknown) host specific factors play an important role in the development of the intestinal bacterial community in each broiler chicken. Furthermore, compartment-specific factors play an important role in the bacterial development of each intestinal compartment within one chicken.
Assuntos
Bactérias/crescimento & desenvolvimento , Galinhas/microbiologia , Intestinos/microbiologia , RNA Ribossômico 16S/genética , Animais , Bactérias/genética , Galinhas/crescimento & desenvolvimento , DNA Bacteriano/genética , DNA Ribossômico/genética , Eletroforese em Gel de Poliacrilamida , Variação Genética , Reação em Cadeia da Polimerase , Fatores de TempoRESUMO
Gastroenteritis caused by Campylobacter spp. infection has been recognized as one of the important public health problems in the developed countries. Outbreaks mostly originate from the consumption of contaminated poultry or infected water. The aim of this study was to determine the bactericidal activity on Campylobacter spp. of organic acids individually and in combinations at different pH levels and times and to compare bactericidal activities with activities of commercially available products. Ten strains of Campylobacter spp. were added in a mixture of water with commercial broiler feed, separately adjusted by four acids: formic, acetic, propionic, and hydrochloric acids, into pH 4.0, 4.5, 5.0, and 5.5. A combination of three organic acids was used in two different formulation ratios: formic:acetic:propionic at 1:2:3 and 1:2:5, at pH 4.0, 4.5, 5.0, and 5.5. All organic acids showed the strongest bactericidal effect on Campylobacter at pH 4.0. In contrast, at pH 5.0 and 5.5, the bactericidal activity of the four acids was low. The combination of organic acids showed a synergistic bactericidal activity at pH 4.5. Interestingly, the effect of the combined organic acids was stronger than the commercial products. Morphological cell changes were studied by transmission electron microscopy to determine the effect of the organic acids on the cell structure of Campylobacter. Some loss of outer membranes of the bacteria could be found in treated groups. Therefore, it can be concluded that organic acids, individually or in combination, have a strong bactericidal effect on Campylobacter spp. Routine application of organic acids to the water supply on poultry farms could prevent or diminish Campylobacter transmission.
Assuntos
Ácidos Acíclicos/farmacologia , Ração Animal/microbiologia , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Ácido Acético/farmacologia , Animais , Infecções por Campylobacter/prevenção & controle , Campylobacter coli/crescimento & desenvolvimento , Campylobacter coli/ultraestrutura , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/ultraestrutura , Galinhas/microbiologia , Contaminação de Alimentos , Formiatos/farmacologia , Gastroenterite/microbiologia , Gastroenterite/prevenção & controle , Humanos , Ácido Clorídrico/farmacologia , Concentração de Íons de Hidrogênio , Microscopia Eletrônica , Propionatos/farmacologia , Saúde Pública , Microbiologia da ÁguaRESUMO
An in vivo experiment was performed with pigs to study the inhibitory effect of fermented feed on the bacterial population of the gastrointestinal tract. Results demonstrated a significant positive correlation between pH and lactobacilli in the stomach contents of pigs in dry feed as well as in the stomach contents of pigs fed fermented feed. Furthermore, a significant positive correlation between the pH and the numbers of bacteria in the family Enterobacteriaceae in the contents of the stomach of pigs fed dry feed was found. In the stomach contents of pigs fed fermented feed, a significant negative correlation was found between the concentration of the undissociated form of lactic acid and the numbers of Enterobacteriaceae. The numbers of Enterobacteriaceae in the contents of the stomach, ileum, cecum, colon, and rectum of pigs fed fermented feed were significantly lower compared with the contents of the stomach, ileum, caecum, colon, and rectum of pigs fed dry feed. The numbers of total lactobacilli were significantly higher in the stomach contents of pigs fed fermented feed and in the ileum contents of one pig group fed fermented feed compared with the contents of pigs fed dry feed. However, the influence of lactobacilli on numbers of Enterobacteriaceae could not be demonstrated. It was concluded that fermented feed influences the bacterial ecology of the gastrointestinal tract and reduces the levels of Enterobacteriaceae in the different parts of the gastrointestinal tract.
Assuntos
Ração Animal , Sistema Digestório/microbiologia , Enterobacteriaceae/crescimento & desenvolvimento , Lactobacillus/crescimento & desenvolvimento , Suínos/microbiologia , Animais , Contagem de Colônia Microbiana , Enterobacteriaceae/isolamento & purificação , Ácidos Graxos Voláteis/análise , Fermentação , Concentração de Íons de Hidrogênio , Lactatos/análise , Ácido Láctico/análise , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismoRESUMO
The standard method to detect Salmonella positive pigs is bacteriological examination of the faeces, but in recent years the use of Salmonella-ELISA's have become available to screen pigs for serological evidence of infection. This study was conducted to monitor the transmission of five different Salmonella enterica serovars (S. Typhimurium, S. Brandenburg, S. Panama, S. Livingstone, and S. Goldcoast) in fattening pigs and to test the feasibility of Salmonella-ELISA, using seeder pigs as a mode of transmission. Serovar dependence in transmission was observed. The Salmonella-ELISA proved to be useful to detect S. Typhimurium and S. Brandenburg in herds but was of limited value to demonstrate S. Livingstone, S. Goldcoast, and S. Panama.
Assuntos
Anticorpos Antibacterianos/biossíntese , Salmonelose Animal/transmissão , Salmonella enteritidis/isolamento & purificação , Doenças dos Suínos/transmissão , Animais , Anticorpos Antibacterianos/sangue , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia , Salmonelose Animal/sangue , Salmonelose Animal/imunologia , Salmonella enteritidis/classificação , Salmonella enteritidis/imunologia , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/imunologiaRESUMO
The purpose of this study was to determine if lairages of pig slaughterhouses can act as a source of contamination of slaughtered pigs with Salmonella. The prevalence and variety of serotypes of Salmonella in the lairages of two pig slaughterhouses were determined, and the efficacy of the usual cleaning and disinfection on the presence of Salmonella was estimated. Lairages of two pig slaughterhouses were sampled three times when pigs were present. Furthermore, these lairages were sampled after the usual cleaning and disinfection, whereas the lairage of one slaughterhouse was sampled an additional time after improved cleaning and disinfection. Samples were collected by swabbing floor and wall surfaces and collecting the residing fluids on the floor throughout the lairage. Salmonella was isolated in 70 to 90% of the samples when pigs were present. The usual cleaning and disinfection reduced the level of contamination with Salmonella to 25% positive samples, whereas improved cleaning and disinfection reduced this level to 10% positive samples. It is concluded that the waiting period in the lairage of at least 2 h contains a substantial risk for slaughter pigs to become infected with Salmonella, especially for pigs originating from Salmonella-free herds. The usual cleaning and disinfection of the lairage were not sufficient to eliminate this risk, whereas an improved procedure for cleaning and disinfection still was unsatisfactory.
Assuntos
Matadouros , Desinfecção/métodos , Salmonelose Animal/microbiologia , Salmonella/isolamento & purificação , Doenças dos Suínos/microbiologia , Animais , Contaminação de Alimentos/prevenção & controle , Países Baixos/epidemiologia , Prevalência , Fatores de Risco , Salmonella/classificação , Salmonelose Animal/epidemiologia , Salmonelose Animal/prevenção & controle , Sorotipagem , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/prevenção & controle , Fatores de TempoRESUMO
The purpose of this study was to show the distribution of Salmonella in slaughtered pigs and the environment of the slaughterhouse. 1,114 samples of slaughtered pigs (six different samples for Salmonella isolation and one serum sample for ELISA on antibodies per pig) and 477 samples of the slaughterhouse environment were collected in two slaughterhouses on two sampling days per slaughterhouse. Salmonella was isolated from one or more samples of 47% of the pigs. The highest prevalence of Salmonella was observed in rectal content samples (25.6%), whereas the lowest prevalence of Salmonella was observed on the carcasses (1.4%). The prevalence of Salmonella in other samples was: 19.6% in tonsils, 9.3% on livers, 9.3% on tongues, and 9.3% in mesenterial lymphnodes. The prevalence of Salmonella in environmental samples was high in the drain water samples in both slaughterhouses (61%) and on the carcass splitter in one slaughterhouse (33%). Salmonella typhimurium was the most frequently isolated serotype in pig samples and environmental samples in both slaughterhouses: 43% of the Salmonella isolates from pigs and 33% of the Salmonella isolates from the environment was S. typhimurium. The results of this study show that Salmonella prevalences in pigs differ a lot, depending on which part of the pig is sampled. Not all different samples of the pig will become available for human consumption, but collecting more than one sample per pig showed that Salmonella can be found in almost the whole pig. The result of surface samples of carcass and liver gives information about hygiene during the slaughter process; the result of tonsils, lymphnodes and rectal contents, combined with the serological result, gives information about infection of the pig before the slaughter process (on the farm, during transport or in lairage). It can be concluded that results of Salmonella isolation of slaughter pigs should always be carefully interpreted, depending on the type of sample that has been collected.