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1.
The presence of enteric Helicobacter species was investigated in poultry (n=130) and in pet and ornamental birds (n=50) using a PCR sequencing method which permits the differentiation of many Helicobhacter species derived from animal tissues. All samples were of Italian origin, except for 21 Guinea fowl from a French flock. About 80% of poultry (chickens, laying hens, Guinea fowl) were positive to Helicobacter DNA. H. pullorum was most frequently (62.1%) identified whereas H. pylori and 3 H. sp. hamster B strains were seen in only 3 cases each. Pet and ornamental birds were all negative. H. canadensis was found in all Guinea fowl from a French farm. This is the first report on the occurrence of this bacterium in poultry.  相似文献   

2.
1. A caecal intubation technique was developed to determine the amount of digesta that enters the caeca of fed and feed-deprived chickens. 2. Dry matter intakes per day for control and caecostomised chickens were not significantly different. 3. For fed and feed-deprived roosters, water intake was significantly increased by caecostomy in control birds and was significantly increased by feeding. 4. Amount of caecal dry matter excretion was significantly increased by feeding, but no difference in caecal water excretion was observed. 5. The ratio of caecal excretion (caecal/total excretion) of dry matter and water tended to decrease in response to feeding. 6. It is concluded that dry matter entry into the caeca represents 18% or 25% of the total dry matter excretion in fed or feed-deprived birds, respectively. Corresponding values for water entry are 17 and 26%. Therefore, the caeca play an important role in water balance.  相似文献   

3.
To determine the efficiency of benzoic acid, a feeding experiment was carried out with 240 one‐day old ROSS 308 cockerels. Birds were divided into three dietary treatments: I (C) – no additives, II (B1) – 0.1% inclusion of benzoic acid, III (B2) – the inclusion of 0.2% benzoic acid. The performance results were similar in birds fed the control diet and the diet with 0.1% of benzoic acid. The dietary inclusion of benzoic acid at 0.2% depressed the growth of broiler chickens (p < 0.05). The dry matter of the digesta increased in the crop and caeca after benzoic acid supplementation. The pH of the caecal contents decreased following benzoic acid supplementation and was the lowest in the B2 group. No differences were found in the pH of the crop, ileal, gizzard digesta and rectum content. Lactic acid bacteria populations were the lowest in the caeca of the B1 group (p < 0.05). Coliform bacteria decreased in the caeca contents following increased benzoic acid supplementation.  相似文献   

4.
The role of birds as sources of Shiga toxin-and intimin-producing Escherichia coli was studied. Fecal samples from live gulls (n=86), pigeons (n=33) and broiler chickens (n=199) from 23 flocks were analyzed for stx and eae by PCR. No stx positive samples were detected. In contrast, eae E. coli were highly prevalent among gulls (40%), and was also found in pigeons (7%) and chickens (57% of the flocks contaminated). The eae positive isolates were analyzed genetically and O-serogrouped. One isolate from a pigeon was found to have stx (2f). The isolates of gulls differed from those of pigeons and chickens, and all eae E. coli isolates from birds differed from human pathogenic strains by the lack of EHEC-hlyA and bfp/EAF as well as distribution of O-serogroups. Thus, birds cannot be regarded as important carriers of zoonotic stx or eae E. coli in Finland.  相似文献   

5.
Salmonella enterica subspecies enterica infection remains a serious problem in a wide range of animals and in man. Poultry-derived food is the main source of human infection with the non-host-adapted serovars while fowl typhoid and pullorum disease are important diseases of poultry. We have assessed cecal colonization and immune responses of newly hatched and older chickens to Salmonella serotypes Enteritidis, Infantis, Gallinarum and Pullorum. S. Enteritidis and S. Infantis colonized the ceca more efficiently than S. Gallinarum and S. Pullorum. Salmonella infection was also associated with increased staining for B-lymphocytes and macrophages in the cecal tonsils of infected birds. S. Enteritidis infection in newly hatched birds stimulated the expression of CXCLi1 and CXCLi2 chemokines in the cecal tonsils, while S. Gallinarum up-regulated the expression of LITAF. In older chickens, S. Enteritidis infection resulted in a significantly higher expression of CXCLi2, iNOS, LITAF and IL-10 while S. Pullorum appeared to down-regulate CXCLi1 expression in the cecal tonsils. Data from spleens showed either no expression or down-regulation of the tested genes.  相似文献   

6.
In situ hybridization was used in a pathogenesis study of three vaccine pathotypes (Delaware variant A, D78, and BursaVac) of infectious bursal disease virus (IBDV). Tissues were excised (bursa, thymus, spleen, proventriculus, and cecal tonsils), fixed in formalin, and paraffin embedded at 12, 24, 48, 72, and 120 hr postinoculation (HPI). With an antisense VP2 gene probe, viral nucleic acid was detected in bursas from both D78- and BursaVac-infected chickens at 24, 48, 72, and 120 HPI. However, viral RNA was detected only in the Delaware variant A-infected birds at 72 HPI. Thymus and spleen were positive in the D78-infected birds at 48 HPI and in the BursaVac-inoculated group at 72 HPI. Viral nucleic acid was not present in detectable levels among any of the tissues tested at 12 HPI. However, by 24 hr, scattered positive lymphoid cells were visualized in the bursal follicles of chickens infected with D78 and BursaVac. In addition, low levels of viral nucleic acids were detected in the thymus and spleen among the D78- and BursaVac-infected birds. The sites of viral replication were consistent between the two vaccine-infected groups (D78 and BursaVac), whereas the chickens infected with Delaware variant A had limited IBDV replication in the bursa.  相似文献   

7.
Localization of Newcastle disease viral nucleoprotein and pathological lesions was evaluated in tissues of 55 indigenous ducks (45 experimentally infected and 10 sentinel ones). In addition, ten Newcastle disease infected chickens were used to ensure that the virus inoculum administered to the ducks produced the disease in chickens, the susceptible hosts. Ducks were killed on day 1, 4, 8 and 14 post-infection. Post-mortem examination was done with six tissues (liver, spleen, lung, caecal tonsils, kidneys and brain) being collected from each bird. The tissues were preserved in 10% neutral formalin for 24 h. They were then transferred to 70% ethanol for histology and immunohistochemical staining. Airsacculitis, necrotic splenic foci, congested intestines, lymphoid depleted caecal tonsils and focal infiltrations by mononuclear cells were the main pathological lesions in infected ducks. Over 28.9% of the infected ducks had Newcastle disease viral nucleoprotein in macrophage-like large mononuclear cells in the caecal tonsils and kidney tubular epithelium. The viral antigens were located in the cytoplasm and nucleolus of the cells. The other organs had no detectable viral antigens. This study shows that the kidneys and caecal tonsils are the likely predilection sites for the virus in ducks. They thus need to be considered as diagnostic indicators for the viral carriage in ducks.  相似文献   

8.
Despite the fact that, in a number of countries, vaccination programmes are extensively used to control Salmonella infection in poultry, information on the immune mechanisms, especially the cellular response, is still needed. The aim of the study was to characterise the B cell and macrophage response in caecum (IgA+, IgM+, IgG+ cells, macrophages), bursa of Fabricius (IgM+ cells, macrophages), and spleen (IgM+ cells) of chicks after oral administration of a non-attenuated Salmonella (S.) typhimurium wild-type strain (infection) or an attenuated commercial live S. typhimurium vaccine strain (immunisation) to day-old chicks as compared to non-treated control birds using immunohistochemistry and image analysis. In caecum, higher counts of IgM-secreting cells were detected in infected animals compared with the controls from day 5 until day 12 of age. In contrast, in treated groups, IgA-secreting cells were found in higher numbers only between day 8 and 12 of age. Infected birds showed a higher number of IgA+ cells in spleen and bursa of Fabricius compared to the controls. In the bursa of Fabricius of immunised and infected birds, a depletion of strongly stained IgM+ cells and macrophages was established between day 5 and 9 indicating a possibly special and independent role of this organ during the immunological reaction against Salmonella organisms. The results suggest that IgM- and IgA-secreting cells are of importance in the caecal immune response of chickens against Salmonella strains. Immunised chickens always showed a weaker immune reaction compared to infected animals. Present findings regarding the B cell reaction within avian caeca prove a participation of both humoral and cellular immunity in defence against Salmonella strains. Immunohistochemical examination of the cellular response (B cells and macrophages) in relevant organs of chickens may be an important tool to evaluate the immunogenic characteristics of potential Salmonella live vaccine candidates.  相似文献   

9.
An experiment was carried out to study the effects of vaccination with Paracox, a live, attenuated vaccine against avian coccidiosis, on broilers isolated from extraneous Eimeria parasites. The study involved 3200 broiler chickens raised in floor pens similar to commercial conditions, but in an initially Eimeria-free environment. Forty percent of the chickens were vaccinated at 3 days of age and given either a basal unmedicated feed or a feed supplemented with the feed antibiotic virginiamycin. Unvaccinated birds were given either the basal feed or feed supplemented either with virginiamycin or the anticoccidial ionophore narasin. At slaughter at 36 days of age vaccinated birds had a lower live weight than non-vaccinated birds. The difference was 4.6% in unmedicated, and 6.0% in virginiamycin medicated chickens. Feed conversion ratio at slaughter was 2.5% higher for unmedicated vaccinated birds, and 1.3% higher for virginiamycin medicated vaccinated birds, compared to respective non-vaccinated groups. There was no significant difference in overall performance of unvaccinated birds given narasin as compared to virginiamycin. At 10 days post vaccination vaccinated birds had a higher number of Clostridium perfringens in the caeca, but there was no difference thereafter. Throughout the experiment, caecal clostridial counts were considerably higher in vaccinated unmedicated birds than in unvaccinated birds given narasin. The number of oocysts shed in the vaccinated groups was very low, but during a subsequent challenge with E. maxima and E. tenella the birds' immunity was found to be satisfactory.  相似文献   

10.
1. The aim was to investigate the effect of grain type (barley or rye) and exogenous enzymes (β-glucanase or xylanase) on the composition of chicken caecal microbiota as examined by classical culturing and molecular techniques (fluorescent in-situ hybridisation (FISH) and terminal-restriction fragment-length polymorphism (T-RFLP)). 2. Plate counting revealed higher total numbers of anaerobic bacteria, lactic acid bacteria and yeasts in caecal contents of birds fed with rye-based diets than in birds fed with barley-based diets. 3. As assessed by FISH analysis, the most abundant bacterial groups in the broiler caeca were Clostridium coccoides-Eubacterium rectale followed by Bacteroides sp., Lactobacillus sp./Enterococcus sp., Bifidobacterium sp. and Enterobacteriaceae. For both cereal types, the enzyme supplementation significantly decreased the relative amount of Enterobacteriaceae. 4. The T-RFLP profiles indicated that the caecal microbiota of birds receiving rye-based diets was more diverse than that of birds fed on barley-based diets. 5. Irrespective of the method applied, the results indicate that the cereal type as well as the exogenous enzyme supplementation influence the microbiota in broiler chicken caeca, and may have the effect of reducing potentially pathogenic Enterobacteriaceae populations.  相似文献   

11.
Over the past 3 years the frequency of Salmonella hadar infections has increased in Belgium in both poultry and humans. Therefore, the course of infection with S. hadar in poultry was investigated. One day-old and 4 week-old specific pathogen-free chickens were orally infected with one of two S. hadar strains, SH1 or SH2. Mortality was 6% (SH1) and 17% (SH2) in birds infected at 1 day-old. Chickens infected at 1 day-old with SH2 showed a mild diarrhoea. The S. hadar faecal excretion in birds infected at 1 day-old remained high throughout the experiment until 12 weeks post-inoculation (pi). Faecal excretion was lower in older birds. Antibodies to S. hadar were observed from 2 weeks pi (SH2, infected at 1 day-old) or 4 weeks pi (SH1, both groups; SH2, chickens infected at 4 weeks of age). The percentage of chickens with antibodies was higher after infection at 1 day-old than after infection at 4 weeks of age. In a second experiment 1 day-old chicks were infected with SH1 and autopsied at regular intervals until 42 days pi. SH1 was isolated from the caeca from 3 h pi onwards and from the liver and spleen from 18 h until 14 days pi. Serous typhlitis and omphalitis were the main lesions. The number of macrophages in the lamina propria of the caecal tonsils was slightly increased from 18 h until 2 weeks pi. In the liver, inflammation was observed in the portal triads and in the sinusoids. This study indicates that infections with S. hadar lead to intense colonisation of the gut and extensive faecal shedding. It may also cause invasive infections in 1 day-old chickens.  相似文献   

12.
1. The effect of washing out the caecal contents on nitrogen utilisation and nitrogen excretion were examined in Single Comb White Leghorn cockerels fed on a 50 g/kg protein diet supplemented with urea. 2. Flushing out the caecal contents with saline in caecally ligated chickens produced a significantly increased nitrogen balance and increased nitrogen utilisation (P<0.05). 3. Washing out the caecal contents significantly decreased uric acid excretion but the treatment had no effect on urea and ammonia excretion. 4. Caecal bacterial contents were significantly decreased by caecal ligation and decreased further by washing out the caecal contents. 5. It is concluded that nitrogen metabolism in chickens is affected by possible changes in caecal fermentation produced by preventing substances from urine and digesta from entering the caeca.  相似文献   

13.
肉鸡鸡白痢沙门菌的分离鉴定   总被引：1，自引：0，他引：1  
2009年5月,北京郊区某肉鸡养殖户的2 000只7日龄雏鸡出现拉白色稀粪,肝脏有黄色结节等症状和病变的疾病。为探索该病病因及制定有效防治措施,对病鸡样品进行了细菌学检验。通过细菌分离、生化试验、PCR及16 S rRNA基因测序鉴定出1株鸡白痢沙门菌。该分离株感染试验鸡能复制出与其临床表现一致的病例并能引起死亡。表明鸡白痢沙门菌是危害北京郊区该养殖户肉鸡的病原。  相似文献   

14.
In this paper we present the results of studies on the infectivity of an isolate of avian pneumovirus (APV) from turkeys to broiler chickens. Two-week-old broiler chicks free of antibodies to APV were exposed either by oculonasal or oral route with a cell cultured APV of turkey origin. Chickens from both APV-inoculated groups exhibited clinical signs that included coughing, sneezing, nasal discharge, and watery eyes during 2-8 days postinoculation. Tissue samples from birds in the APV-inoculated group were positive for APV by polymerase chain reaction (PCR) up to 9 days postinoculation. Samples of blood from both oculonasally and orally infected chickens were positive for APV. Intestinal samples from chickens infected with APV orally were positive for the presence of APV on PCR up to 9 days postinoculation. APV was reisolated from samples taken from chickens in both groups inoculated orally and oculonasally. Sera from birds exposed by the oculonasal or by the oral route showed the presence of APV-specific antibodies.  相似文献   

15.
Four delivery routes, via, feed, water, litter and oral gavage, were examined for their efficacy in delivering a novel probiotic of poultry origin, Lactobacillus johnsonii, to broilers. Seven treatments of 6 replicates each were allocated using 336 one-day-old Cobb broiler chicks. The treatments consisted of a basal diet with the probiotic candidate, L. johnsonii, added to the feed, and three treatments with L. johnsonii added to the drinking water, sprayed on the litter, or gavaged orally. In addition, a positive control treatment received the basal diet supplemented with zinc-bacitracin(Zn B, 50 mg/kg). The probiotic strain of L.johnsonii was detected in the ileum of the chicks for all four delivery routes. However, the addition of L.johnsonii as a probiotic candidate did not improve body weight gain, feed intake and feed conversion ratio of broiler chickens raised on litter during the 5-week experimental period regardless of the route of administration. The probiotic treatments, regardless of the routes of delivery, affected(P 0.05) the pH of the caecal digesta and tended(P = 0.06) to affect the p H of the ileal digesta on d 7, but the effect disappeared as the birds grew older. All probiotic treatments reduced the number of Enterobacteria in the caeca on d 21, and tended(P 0.054) to reduce it in the ileum and caeca on d 7 and in the ileum on d 21 compared with the controls. The probiotic also tended to increase the number of lactic acid bacteria and lactobacilli in the ileum and caeca on d 7, but this trend was not evident on d 21. The trend appeared most pronounced when the probiotic was delivered orally or via litter. The probiotic also decreased(P 0.05) the population of Clostridium perfringens rapidly from an early age to d 21 in the caeca, leading to a3-fold decrease in the number of C. perfringens between d 7 and 21. It also showed that the probiotic treatment presented the lowest number of C. perfringens in the caeca. Delivery of the probiotic through feed, water and litter increased(P 0.01) the weight of the pancreas on d 21, but the probiotic did not affect other morphometric parameters of the gut. Furthermore, the probiotic did not affect the p H and the concentrations of short chain fatty acids and lactic acid in either the ileum or caeca.  相似文献   

16.
Experimental infections of Salmonella typhimurium, S. agona, S. enteritidis or S. infantis were studied in chicks infected with Eimeria tenella. In all experiments, 4-d old birds were given 5 daily oral doses of approximately 10(4) salmonella organisms per bird. One day before this inoculation one group of birds received a single dose, in the range 1 X 10(4) to 4 X 10(4) sporulated oocysts of E. tenella per os whilst the other group was not inoculated and served as the control. Chicks were examined post morten 7, 10 or 14 d after receiving coccidia. With S. typhimurium infection, the number of salmonellas in the caeca of the E. tenella-infected birds was greater than in those infected only with salmonella. With S. agona and S. enteritidis, the counts of salmonella in the caeca and the numbers of birds positive for salmonella in the caeca and liver were greater in the E. tenella-infected birds. The rate of infection of S. infantis was not increased by caecal coccidiosis.  相似文献   

17.
Newcastle disease viruses isolated from chickens and guinea fowl were characterized as viscerotropic, velogenic strains on the basis of their mean death time, intracerebral pathogenicity index, intravenous pathogenicity index and cloacal and conjunctival mean death time. The pathogenesis of the disease caused by both the strains was studied in 4-week-old guinea fowl. Both strains had an incubation period of 5 days and the birds showed dullness, depression, anorexia, diarrhoea and paralysis of the legs. They also exhibited nervous signs such as incoordination, muscle tremors and trembling of the neck at the advanced stage of the disease. Mortality reached 52% in the group infected with the chicken isolate but it was only 8% in the birds infected with the guinea fowl isolate. No specific changes were observed at post-mortem examination except haemorrhages at the tip of the glands of the proventriculus and in the caecal tonsil. Changes in the lymphoid organs and brain were always present in both the groups. Despite the low mortality, the guinea fowl isolated had multiplied in various organs in the birds. In both groups, the frequency of virus isolation increased from 5 to 10 days post infection.  相似文献   

18.
The present study describes the micromorphology of the small intestine and caeca of wild and captive willow grouse. The micromorphology of the small intestine was similar in wild and captive birds, while typical differences were apparent in the caeca, Wild grouse had ciliated epithelium without goblet cells in the neck part of the caeca, captive birds had strongly atrophied cilia and a high number of goblet cells. The epithelium of the body part of caeca of wild birds lodged a great number of spiral-shaped microorganisms and amoebae, which were absent in captive birds. Both the caecal villi and the longitudinal folds were much larger in wild than captive grouse. In the captive grouse the caecal lamina propria was heavily infiltrated with mono-nucleated cells and very often also with polymorphonucleated heterophilic leucocytes.Since only first generation captives were used in this study, the differences in gut morphology of captive and wild grouse must be due to different food and environmental conditions and not to genetic selection.  相似文献   

19.
采集临床疑似患鸡白痢雏鸡的肝、脾、肺等组织病料进行细菌分离培养,在营养琼脂平板、麦康凯琼脂平板和S.S琼脂平板上生长出均一、无色、半透明、表面光滑、闪亮、隆起、边缘整齐的针尖大小菌落。细菌为革兰氏阴性、两端稍圆、中等大小的细长杆菌,单在,不能运动。应用微生物自动分析系统编码鉴定该病原为鸡白痢沙门氏菌。  相似文献   

20.
To construct a novel live Salmonella Enteritidis (SE) vaccine candidate, SE was genetically engineered using the allelic exchange method to delete two virulence genes, lon and cpxR. The lon gene deletion is essential to impair Salmonella replication and avoid overwhelming systemic disease in the host. The cpxR gene deletion is needed to enhance the ability of bacteria to adhere and invade the host cell. Scanning electron microscopy revealed that the derivatives JOL917 (Δlon), JOL918 (ΔcpxR), and JOL919 (Δlon/ΔcpxR) had increased surface fimbrial filamentous structures. Significant elevations of extracellular polysaccharide and FimA expression were observed for the derivatives compared to the parental wild type JOL860, while biochemical properties of the derivatives were not altered. In the safety examination by inoculation of the derivatives in chickens, gross lesion scores of the liver, spleen, kidney, small intestine and caecal tonsils were moderate in the JOL917 and JOL918 groups, and significantly lower in the JOL919 group than those of the JOL860. Bacterial counts from the spleen and caeca of the JOL917 and JOL918 groups were moderate, and significantly reduced in the JOL919 group compared to the JOL860 group. In addition, only the JOL919 group showed significantly lower bacterial counts in the faecal samples than those of the JOL860 group. Significant elevations of IgG and secretory IgA levels observed in the derivative groups, while the JOL919 and JOL860 groups showed a potent lymphocyte proliferation response as compared to those of the control group. In the protection efficacy examination, JOL919 immunized group showed significantly lower depression, lower gross lesion in the liver and spleen, and lower number of the SE positive internal organs than those of the control group against a virulent wild type SE challenge.  相似文献   

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