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1.
Twelve large white turkey hens were immunized with a commercially available Bordetella avium bacterin. Hens and eggs were tested using an enzyme-linked immunosorbent assay (ELISA) to determine the response to the bacterin. Three hundred poults were then obtained from two commercial flocks, the hens of one flock having been immunized with the same bacterin used on the group of 12 turkeys. Titers of the poults were monitored for 7 weeks, and poults were challenged by exposure to infected poults at 1, 7, 14, and 21 days post-hatch. Hens produced an antibody response following immunization, with a parallel antibody response being detected in eggs. Maternal antibodies were present in poults from immunized hens. Poult titers declined to near the level of poults from unimmunized hens by 14 days of age. Poults from immunized hens challenged at 1 and 7 days were resistant to development of clinical disease and gross lesions, whereas all poults from unimmunized hens exhibited clinical signs and gross lesions. After 14 days, the resistance of both groups to development of clinical disease, became near equal, neither group being affected as severely as the unimmunized hens challenged at days 1 and 7. Six commercial turkey breeding flocks and their progeny that had not been vaccinated for B. avium and had no history of B. avium infection were evaluated with the B. avium ELISA. There were variations between the flocks, with poult titers reflecting those found in the hens. 相似文献
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Protection of turkey poults from Bordetella avium infection and disease by pili and bacterins 总被引：1，自引：0，他引：1
The role of pili in protection against Bordetella avium infection in turkey poults was studied. An isolate that produced the largest number of pili under growth conditions developed in our laboratory was used for preparation of pili and bacterin and for challenge. The pili were isolated, purified, examined by electron microscopy, and tested for purity by gel electrophoresis. Poults were vaccinated with oil-adjuvant pili, formaldehyde- or merthiolate-inactivated bacterins, or a commercial bacterin. Poults were vaccinated once or twice subcutaneously at different ages and challenged intranasally with a pathogenic B. avium isolate 5 days following the last vaccination. A few vaccinated birds had very mild clinical signs. B. avium was isolated from the sinuses of a few vaccinated birds, and growth was scanty. The mean colony counts from tracheal sections was significantly higher (P less than 0.1) in unvaccinated challenged poults than in vaccinated challenged poults. It is postulated that B. avium pili are important immunogens in turkey poults. 相似文献
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Immune response of poults following intranasal inoculation with Artvax vaccine and a formalin-inactivated Bordetella avium bacterin 总被引：1，自引：0，他引：1
Poults 3 weeks and older developed temporary tracheal resistance to intranasal challenge following inoculation of either Artvax vaccine or formalin-inactivated Bordetella avium bacterin by the intranasal and eyedrop routes. Resistance usually persisted for 3-4 weeks after B. avium challenge. However, with constant exposure to infected controls, the vaccinated birds eventually developed tracheal infection. Day-old poults did not respond to either the Artvax or the bacterin and were completely susceptible to challenge. Two-week-old poults responded to some degree, but poults 3 weeks old and older responded best. Poults inoculated with bacterin by aerosol or by drinking water did not respond as well as those inoculated by the intranasal and eyedrop routes. When poults were given a single subcutaneous injection at 3 weeks of age and challenged 2 weeks later, three of five resisted infection for 18 days. 相似文献
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Electrocardiograms (ECGs) were recorded from turkey poults infected with the W isolate of Bordetella avium. Strip chart data (amplitudes and intervals) were measured at 7, 14, 21, and 28 days postinoculation and compared with data from uninoculated controls. B. avium infection altered P-, RS-, and T-wave amplitudes, as well as P-R and S-T intervals throughout the 4-week experimental period. Heart rates were similar over the 4-week period in control poults, while rates in the infected birds were variable. Alterations in ECGs associated with B. avium infection appeared to be the result of disturbances in the cardiovascular system and may be associated with the pathogenicity of the organism in turkey coryza. 相似文献
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M Ianconescu R H McCapes R A Bankowski B J Kelly G Y Ghazikhanian 《Avian diseases》1985,29(2):356-363
The incidence of hemorrhagic enteritis (HE) infection in California turkeys was studied by testing 2220 turkey blood samples from 173 flocks for HE virus (HEV) antibody by the enzyme-linked immunosorbent assay (ELISA). Maternal antibody was detected at 1 day of age in all flocks tested, and it vanished after 3 weeks. Acquired HEV antibody appeared at 8 to 10 weeks, and 100% of the meat and breeder turkey flocks were positive after 11 weeks of age. HEV infection occurred earlier in the meat flocks than in the breeder flocks, and it also occurred earlier during summer than during the fall and winter months. 相似文献
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Six laboratory experiments were designed to determine whether poults infected with the nonpathogenic Bordetella avium-like (BAL) bacteria would develop immunity to B. avium (BA), the causative agent of turkey coryza. The BAL bacteria were isolated from poults given that organism, but few colonies were observed by 3 weeks postexposure. No serum-agglutinating antibody to the BAL bacterium was detected in poults exposed to that organism. Poults exposed to BAL bacteria either once or twice at different ages were not protected from infection or disease following experimental challenge between 1 and 7 weeks of age with pathogenic BA. 相似文献
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Observations on Alcaligenes faecalis infection in turkeys 总被引：6，自引：0，他引：6
Experiments were initiated to study the pathogenicity of 5 Alcaligenes faecalis isolates in specific-pathogen-free poults. The isolates were recovered from commercial flocks suffering from a respiratory disease. There were no differences between cultural or biochemical characteristics of the isolates, but differences in antibiotic sensitivity were detected. All 5 isolates were capable of initiating a respiratory disease in poults similar to that seen in the early stages of turkey coryza. The infection, clinical signs, and lesions were limited to the upper part of the respiratory tract, but there were substantial differences in the severity of disease initiated by different isolates. There were also differences in the persistence of infection in the host. Secondary infections in the tracheas and sinuses were higher in poults infected with A. faecalis. The disease observed in the experimentally infected birds was milder than in 4 naturally infected flocks that also had complicating Escherichia coli infections. There was no evidence of infection with infectious bursal disease virus in 4 naturally occurring outbreaks in Ohio. It is proposed that the term turkey coryza be used to describe the disease initiated by A. faecalis. 相似文献
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Hafez HM 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2001,48(7):547-550
Four meat turkey and one turkey breeding flocks were surveyed for antibodies against reticuloendotheliosis virus (REV) at different intervals using commercial enzyme-linked immunosorbent assays. In addition, serum samples collected from 18 flocks at different ages were also tested for antibodies against REV. No antibodies were detected in any of the four meat turkey flocks that were surveyed. In the breeder flock, 20%) of tested samples from 1-day-old poults were positive. Between the fourth and 12th weeks all samples that were tested yielded negative results. At 16 weeks of age 15% of samples yielded a positive reaction, but antibodies could not be detected 4 weeks later. Examination of serum samples from 18 different flocks at various ages revealed that antibodies could be detected in five flocks. The percentage of positive sera per flock ranged between 10 and 40%. 相似文献
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An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of antibodies in turkey serum to hemorrhagic enteritis virus. The ELISA antigen was extracted from turkey spleens and partially purified with fluorocarbon. Antibodies were demonstrated in serum samples of breeding and meat flocks that had been naturally exposed to infection. These samples were also examined in parallel by agar-gel precipitin (AGP); most of the sera were AGP-positive. ELISA, however, was more sensitive in detecting antibodies in day-old sera that were AGP-negative. The passively acquired antibodies were no longer detected by 4 weeks of age. A brisk but short-lived secondary response was detected by ELISA in the sera of turkeys immunized with beta-propiolactone-inactivated extract of infected spleens. 相似文献
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The pathogenesis of hemorrhagic enteritis in turkey poults infected with hemorrhagic enteritis virus (HEV) at 3 days or at 2 or 5 weeks of age was compared with pathogenesis in poults that had been chemically bursectomized neonatally and exposed to cell-culture-propagated virus at 2 or 5 weeks of age. Conventional poults exposed to HEV at 2 or 5 weeks developed clinical disease, and mortality ranged from 38% to 100%. In addition to the splenic and intestinal lesions usually seen with HEV infection, the pancreas, bursa of Fabricius, and thymus were also affected. In contrast, although they were free from detectable maternal antibody, poults infected with HEV at 3 days of age failed to develop clinical disease or mortality; however, virus was demonstrated by histological and electron microscopic examinations in spleens of these poults. Neonatal chemical bursectomy completely prevented the clinical signs, gross lesions, and mortality induced by HEV in poults at 2 or 5 weeks of age. These findings strongly suggest that an intact bursa is necessary for HEV to induce disease in turkeys. 相似文献
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Four laboratory experiments were designed to study the efficacy of the only available commercial vaccine for turkey coryza, Art-Vax. Poults were vaccinated either once or twice at different ages and challenged with pathogenic Alcaligenes faecalis. In another study, commercial turkeys vaccinated at 1 and 12 days of age on a commercial farm were brought to the laboratory for challenge with pathogenic A. faecalis. Both the laboratory- and field-vaccinated poults were given the manufacturer's recommended dosage of the vaccine strain. Regardless of the vaccine schedule or source of poults, the vaccine was not effective in protecting challenged turkeys from infection. Furthermore, the vaccine was not effective in protecting poults less than 3 weeks of age from disease, but it was effective in protecting poults more than 3 weeks of age from disease. These results indicate that although vaccinated turkeys older than 3 weeks of age were not susceptible to disease, they were susceptible to infection and could act as carriers of field strains of A. faecalis, thus perpetuating the risk of infection to flocks subsequently raised in the same buildings. 相似文献
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Five components (selenium, glutathione peroxidase, copper, superoxide dismutase, and vitamin E) of the antioxidant system of turkey poults were examined to determine if they play any role in the knockdown (KD) syndrome. All flocks were provided with feed formulated to contain monensin at 54-60 g/ton. Flock data were analyzed as a case-control study with three treatment groups (KD-affected and unaffected turkey poults from a KD flock and poults from an unaffected flock [control]). Affected turkey poults had lower (P < 0.001) serum vitamin E levels compared with unaffected poults from KD flocks or poults from unaffected flocks. No significant differences were observed for the other parameters evaluated but there was a trend towards lower copper and superoxide dismutase values in affected birds. It appears that serum vitamin E concentrations in turkey poults may play a significant role in susceptibility to or protection against KD syndrome. Other components of the antioxidant system may also be involved, and complex interactions among several body systems may be critical. 相似文献
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Jankowski J Zduńczyk Z Sartowska K Tykałowski B Stenzel T Wróblewska M Koncicki A 《Polish journal of veterinary sciences》2011,14(3):353-358
The aim of this study was to verify the hypothesis that the health and growth of turkey poults may be improved by supplementing diets fed to parent flocks with available selenium. Experimental poults originated from parent flocks fed with diets containing 0.3 mg/kg inorganic selenium (control group Se(M)) and organic selenium (experimental group Se(O)). Egg yolk selenium content was comparable in both flocks (0.72 and 0.70 mg/kg d.m., respectively). Eggs from the Se(O) flock had a significantly lower content of thiobarbituric acid reactive substances - TBARS (31.13 vs. 53.10 nmol/g, p > 0.001). Se(O) group poults were characterized by higher activity of glutathione peroxidase (7.54 vs. 5.92 U/mL, P = 0.001) and superoxide dismutase (89.30 vs. 79.23 U/mL, P = 0.026). The thigh muscles of Se(O) group birds had significantly higher selenium concentrations (0.74 vs. 0.57, p = 0.045) and a significantly lower TBARS content (38.42 vs. 65.01, p = 0.001). No differences were found between the groups with respect to the content of total protein, albumins and uric acid, and the activites of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (DLH) in day-old poults. On day 28, groups Se(O) and Se(M) differed in the activity of ALT (20.50 vs. 26.33, p = 0.05) and SOD (87.29 vs. 100.02 U/mL, p = 0.035). There were no differences between the groups regarding the percentages of T lymphocyte subpopulations CD4+, CD8+, CD4+CD8+ and B lymphocyte subpopulations (IgM+) at 1 and 28 days of age. Over the experimental period, mortality rates were similar in both groups (7.32 and 8.87%), and so were the final body weights of birds (1108 vs. 1135 g). The results of the study show that the dietary supplementation of organic selenium in turkey parent flocks reduces the rate of oxidation processes in the egg and in the tissues of newly-hatched poults, yet it has no effect on the analyzed parameters of cell-mediated immunity and the growth performance of birds during the first five weeks of their life. 相似文献
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The conditions under which infection with Histomonas meleagridis could spread from directly inoculated turkey poults to uninoculated poults without the aid of invertebrate hosts or vectors was investigated in several experiments. In three experiments in battery cages, uninoculated poults were commingled with directly infected birds on pine-shaving litter. Directly exposed birds were inoculated per cloaca with H. meleagridis by means of a plastic pipette tip attached to a 10-ml syringe or orally gavaged with fresh cecal droppings from donor turkeys 4 days postinoculation (PI). Of the cloacally inoculated controls in these experiments, 31 of 44 (70.5%) birds had severe lesions ofhistomoniasis at 14 days PI, whereas none of the orally gavaged birds became infected. Histomoniasis developed in 11 of 36 (30.5%) birds allowed to commingle with inoculated birds. In other treatments, poults were allowed only contact with droppings from directly inoculated birds after the infected birds were removed from the cages. This was done for a single period of 1 hr or repeated five times. Four of 32 birds (12.5%) became infected in this way after the single exposure, whereas only four of 44 birds (9.1%) exposed five times developed lesions. In a comparison of floor materials, 35 of 35 control birds inoculated per cloaca developed severe liver and cecal lesions, irrespective of litter. Uninoculated birds allowed to commingle with infected birds on paper or pine shavings became severely infected in all cases (12/12 and 12/12 birds, respectively), whereas only 33% of those on wire-floored cages became infected (4/12). These results suggest that transmission of infection is more likely to occur as a result of direct contact between birds than from contact with litter or fecal material. 相似文献
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The epidemiology of infectious bursal disease (IBD) was studied by serology and sometimes by visual examination of the bursa of Fabricius in poultry flocks in Queensland during 1976–1979.
Ten flocks, each of approximately 30,000 meat breeding chickens, were surveyed. All chickens had maternally-derived antibody against IBD virus (IBDV) at hatching and active antibody was not detected while the chickens were brooded on rearing farms. When distributed to breeding farms, 7 of the flocks developed antibody when 11 to 25 weeks of age. The remaining 3 flocks were vaccinated by infection of 10% of the birds and within 4 weeks more than 80% of the chickens had developed precipitating antibody to IBDV.
Blood samples of 20 to 30 broiler chickens were collected at slaughter (7 to 9 weeks of age) from each of 312 broiler flocks raised on 37 contract farms. While the samples from 21 flocks were without detectable antibody to IBDV, all serum samples for 263 flocks contained antibody. The ratio of bursal weight to bodyweight was significantly lower in birds from 144 flocks having antibody to IBDV than in birds from 10 flocks that were without detectable antibody. In sequential studies, IBDV antibody became demonstrable in 27 of 30 flocks when the chickens were one to 6 weeks of age and was accompanied by bursal atrophy.
Serological investigation of 4 flocks of layer breeding chickens on a multi-age farm at approximately monthly intervals resulted in antibody to IBDV being detected at every examination.
Serological tests and bursal examinations were carried out weekly in 2 flocks each of 4000 layer chickens between one and 20 weeks of age. Serum antibody developed in one flock at 4 weeks of age and in the other at 17 weeks of age. In both flocks, bursal atrophy occurred concurrently with the development of antibody. 相似文献
Ten flocks, each of approximately 30,000 meat breeding chickens, were surveyed. All chickens had maternally-derived antibody against IBD virus (IBDV) at hatching and active antibody was not detected while the chickens were brooded on rearing farms. When distributed to breeding farms, 7 of the flocks developed antibody when 11 to 25 weeks of age. The remaining 3 flocks were vaccinated by infection of 10% of the birds and within 4 weeks more than 80% of the chickens had developed precipitating antibody to IBDV.
Blood samples of 20 to 30 broiler chickens were collected at slaughter (7 to 9 weeks of age) from each of 312 broiler flocks raised on 37 contract farms. While the samples from 21 flocks were without detectable antibody to IBDV, all serum samples for 263 flocks contained antibody. The ratio of bursal weight to bodyweight was significantly lower in birds from 144 flocks having antibody to IBDV than in birds from 10 flocks that were without detectable antibody. In sequential studies, IBDV antibody became demonstrable in 27 of 30 flocks when the chickens were one to 6 weeks of age and was accompanied by bursal atrophy.
Serological investigation of 4 flocks of layer breeding chickens on a multi-age farm at approximately monthly intervals resulted in antibody to IBDV being detected at every examination.
Serological tests and bursal examinations were carried out weekly in 2 flocks each of 4000 layer chickens between one and 20 weeks of age. Serum antibody developed in one flock at 4 weeks of age and in the other at 17 weeks of age. In both flocks, bursal atrophy occurred concurrently with the development of antibody. 相似文献
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M Ianconescu R A Bankowski R H McCapes G Y Ghazikhanian B J Kelly 《Avian diseases》1985,29(2):364-372
An enzyme-linked immunosorbent assay (ELISA) was developed for detecting paramyxovirus type 3 (PMV-3) antibody. This test had a higher sensitivity than the hemagglutination-inhibition test, and no cross-reactivity with various paramyxoviruses or avian pathogens was detected when the sera were tested diluted 1:200. The incidence of PMV-3 infection in California was studied by testing 2037 turkey sera from 174 meat and breeder flocks for the presence of PMV-3 antibody using the ELISA. The age at which the infection occurs was around 5 to 8 weeks for meat flocks and 10 to 12 weeks for breeder flocks. Infection with the PMV-3, as determined serologically, was more frequent than manifested cases of disease, and 95.2% of the flocks aged over 11 weeks had PMV-3 antibody. No typical manifestations of PMV-3 disease (respiratory disease plus drop in egg production) were observed, probably because of the early infection which occurred before laying age. 相似文献
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Recently, pathogenesis studies, using genetically distinct turkey-origin reoviruses (TRVs), revealed that poults infected with certain TRV isolates had moderate to severe bursal atrophy, suggesting virus-induced immune dysfunction. In order to characterize the effect of TRV infection on the turkey immune system, classical assays were undertaken to quantify the humoral and cell-mediated immune responses in small Beltsville and broad-breasted white poults infected with the TRV isolate NC/SEP-R44/03. A marked effect on the cutaneous basophil hypersensitivity response, and on the antibody response to Newcastle disease virus (NDV) exposure, was noted in commercial and specific pathogen free (SPF) poults inoculated with NC/SEP-R44/03 at three days of age. Moderate to severe bursal atrophy, similar to that noted previously in SPF poults, occurred in commercial poults inoculated at three days of age. This immune dysfunction and bursal atrophy was not present in commercial poults inoculated at three weeks of age. 相似文献