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We designed this study to compare the replication potential of turkey coronavirus (TCV) and its effect in chickens and turkeys and to study the effect of singleand combined infection of turkey poults with TCV and astrovirus. We studied the pathogenicity of TCV in experimentally inoculated turkey poults and chickens by observing the dinical signs and gross lesions. Two trials were conducted with 1-day-old and 4-wk-old specific-pathogen-free turkey poults and chickens. One-day-old turkey poults developed diarrhea at 48 hr postinoculation. Poults euthanatized at 3, 5, and 7 days postinoculation had flaccid, pale, and thin-walled intestines with watery contents. The 4-wk-old turkeys had no clinical signs or gross lesions. One-day-old and 4-wk-old chicks developed no clinical signs or gross lesions although the TCV was detected in gut contents of the birds throughout the experimental period (14 days). In another experiment, mean plasma D-xylose concentrations in 3-day-old turkey poults inoculated with TCV, turkey astrovirus, or a combination of both viruses were significantly lower than in the uninoculated controls. 相似文献
3.
Seeds of horse chestnut (Aesculus hippocastanum), Ohio buckeye (A glabra), and yellow buckeye (A octandra) were tested for toxicity to 2-week-old Leghorn chicks and adult female Syrian hamsters. The LD50 of the water soluble portion of alcoholic extracts of horse-chestnut seeds (for hamsters and chicks) and of dried, powdered seeds (chicks only) was determined. The LD50 for a single dose of extract from horse-chestnut seeds was 10.6 mg/g of body weight for chicks and 10.7 mg/g of body weight for hamsters. The LD50 for chicks given 2 consecutive daily doses of horse-chestnut seed was 6.5 mg/g. Toxic signs included depression, muscular incoordination, paralysis, coma, and death. Extracts of seeds of Ohio buckeye were nontoxic to chicks and hamsters when fed at 80 mg/g. One of 5 hamsters died after dosing for 5 days with 80 mg/g of extract of seeds of yellow buckeye/g. 相似文献
4.
Sixty-four, 10-week-old turkeys were inoculated with a highly virulent field isolate (86-1913) of Pasteurella multocida serotype A:3,4 by an oculo-nasal-oral route. Inoculated turkeys were examined at 4, 8, 16, 20, and 24 hours post-inoculation for bacteremia and histologic lesions. Bacteremia was detected in one of six turkeys 8 hours after inoculation and in four of six turkey poults at 16 hours post-inoculation. Pasteurella multocida was isolated from the spleens of two turkeys at 8 hours and from the spleens of all six poults 16 hours after inoculation. Peak concentrations of P. multocida reached 10(9) colony forming units per ml of blood. At 4 to 8 hours post-inoculation, isolate 86-1913 produced a fibrinopurulent bronchopneumonia followed by severe pulmonary necrosis, pleuritis, vasculitis; and, at 16 to 24 hours post-inoculation numerous extracellular bacteria were observed. Hepatic lesions included focal heterophil aggregates 8 hours after inoculation; these progressed to hepatic necrosis. Numerous extracellular bacteria within sinusoids were present 16 to 24 hours after inoculation. At 16 to 24 hours post-inoculation, there was degeneration of periarteriolar reticular cells in the spleen; these cells progressed to coalescing coagulative splenic necrosis with extracellular bacterial colonies. A second group of 41, 10-week-old turkeys, previously vaccinated with the Clemson University strain of P. multocida serotype A:3,4, were challenged with isolate 86-1913.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Twenty-four 4-week-old poults, free from Mycoplasma meleagridis and M. gallisepticum, were inoculated with a velogenic viscerotropic strain of Newcastle disease virus. Clinical signs (gasping, coughing, and dyspnea) developed 4-5 days postinoculation, continued until nervous derangement appeared, and then (usually 3 days after initial clinical signs appeared) declined in severity. Prominent nervous signs were paresis and paralysis of the extremities, with pronounced head-shaking. The most constant gross lesions detected involved the airsacs. The abdominal sacs of a few poults contained a large accumulation of yellowish, cheesy exudate and there was cloudiness of the thoracic airsacs of all inoculated poults. A few turkeys had tracheitis with some catarrhal exudates and casts in the lower part of the tracheal lumen. Congestion of lepto-meningeal vessels usually correlated with the severity of the nervous signs. The histologic lesions were characterized by both degenerative and proliferative changes with predominantly mononuclear cell and heterophil infiltrations throughout the body. The obvious lesion seen in the recovery stage of the disease was proliferation of lymphofollicular nodules in the parenchymatous organs. 相似文献
6.
Skeletal deformities, a major contributing factor to economic losses in market-age turkeys, may be associated with the poult malabsorption syndrome. A study was performed to determine whether the naturally occurring malabsorption syndrome produces skeletal lesions in turkeys at market age. Poults were placed on litter on which poults had previously developed malabsorption. Exposed poults developed enteric disease with 21% mortality during the first 3 weeks. Controls had no enteric disease and no mortality. At the end of the study, 20-week-old exposed turkeys weighed 0.621 kg (5%) less than controls and had a higher incidence of angular limb deformities with significantly higher angulation scores. Exposed turkeys also had a greater incidence of rotated tibias and bowed tibias. The mechanical property of tibial shear strength was significantly lower in turkeys that had survived the earlier poult malabsorption syndrome. 相似文献
7.
P M Hocking 《British poultry science》1992,33(2):253-269
1. Turkey females were fed ad libitum or restricted from 6 weeks of age to achieve mean body weights of 0.6 of ad libitum fed birds on photostimulation at 18, 24 or 30 weeks of age. Body weight, food intake, egg production and hatchability were recorded to 54 weeks of age. 2. Restricted turkeys were fed ad libitum after first egg or 36 weeks of age. Food intake after 30 weeks of age averaged 170 g/bird/d and was similar for all treatments. At 54 weeks of age, restricted turkeys photostimulated at 24 and 30 weeks were not as heavy as turkeys photostimulated at 18 weeks and ad libitum fed turkeys. 3. A large proportion of restricted turkeys photostimulated at 18 weeks of age did not commence lay until 30 to 40 weeks and a significant number of restricted birds photostimulated at 24 weeks had short laying cycles. Restricted birds photostimulated at 30 weeks came into lay and showed similar persistency of lay to ad libitum fed turkeys. 4. Ad libitum fed turkeys laid 115.0, 122.0 and 101.0 and restricted turkeys 92.4, 99.5 and 103.4 eggs when photostimulated at 18, 24 and 30 weeks, respectively. The number of non-settable eggs was lower in restricted compared with ad libitum fed turkeys and declined with age at photostimulation. 5. Egg size at the end of the experiment was similar for ad libitum fed turkeys and restricted birds photostimulated at 18 weeks but was 2.3 g lower for restricted birds photostimulated at 24 and 30 weeks of age. 6. Hatchability was higher, and the proportion of second quality poults was lower with eggs from restricted turkeys. The mean numbers of poults hatched were 59.9, 75.1 and 66.0 for ad libitum fed and 71.7, 65.7 and 79.4 for restricted turkeys photostimulated at 18, 24 and 30 weeks of age. 相似文献
8.
J L Richard S J Cysewski A C Pier G D Booth 《American journal of veterinary research》1978,39(10):1674-1679
The effect of T-2 toxin (trichothecene mycotoxin) consumption on Broad-Breasted White turkey poults and White Leghorn chicks was studied. Groups of ten 8-day-old poults were fed rations containing T-2 at 10 ppm, 2ppm, or 0 ppm (controls) for a period of 4 weeks; a 4th group (inanition control) was fed control rations equal to the amount consumed by the group fed rations containing T-2 at 10 ppm during the previous 24 hours. A similar experimental design was used to study the effect of the toxin on 1-day-old chicks. The thymus glands of the poults given the feed containing 10 ppm were markedly decreased in size compared with thymus glands from poults in the control group, 0.182 vs 0.331 (percentage of body weight). There was no significant (P less than or equal to 0.05) decrease in thymus gland size in poults given 2 ppm or in the inanition controls. Dietary treatment did not appear to affect the size of the bursa or spleen of the poults. Histopathologic examination of thymus glands from poults given 10 ppm of T-2 revealed a depletion of cortical lymphocytes. Chicks appeared less sensitive to T-2 toxin than did the poults. There was no effect by any dietary treatment on the size of the thymus gland, bursa, or spleen of chicks. Reductions were noticed in feed efficiency and weight gain. There was no effect of T-2 toxin on agglutinating antibody formation to Pasteurella multocida bacterin. 相似文献
9.
Antibiotic aerosolization: the effect on experimentally induced Alcaligenes rhinotracheitis in turkeys 总被引：1，自引：0，他引：1
Oxytetracycline hydrochloride was delivered by aerosol twice daily for 3 days to uninfected turkeys and to turkeys experimentally inoculated with Alcaligenes faecalis. The clinical, microbiological, and histological changes in the upper respiratory tracts were studied. No lesions were observed in the tracheas of uninoculated poults exposed to the aerosol. In experimentally infected poults, clinical signs included ocular and nasal discharges and open-mouthed breathing. Histologic lesions included progressive bacterial colonization of ciliated epithelium, loss of cilia, depletion of mucin from goblet cells, and accumulation of inflammatory cells within the tracheal lumen. Aerosolization of oxytetracycline effected a temporary decrease in bacterial colonization and a delay in clinical signs and histologic lesions in infected treated poults compared with untreated infected poults. Bacterial colonization and histologic lesions in the tracheas of both treated and untreated infected poults were similar by 4 days after the treatment was discontinued. This study indicates additional research with bactericidal antibiotics is needed to further evaluate antibiotic aerosolization as a treatment for alcaligenes rhinotracheitis. 相似文献
10.
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
11.
Histomonosis (syn. histomoniasis) is a parasitic disease which affects predominately turkeys but also other avian species. Concurrent with the ban of therapeutic and prophylactic substances, the disease, caused by the flagellated protozoon Histomonas meleagridis, is more frequently reported. Due to somewhat diverse results reported in the past, a well-characterized culture was used in the present study to investigate the possible influence of certain parameters on the outcome of the disease. For this study, turkeys were infected with different doses of the mono-eukaryotic culture Histomonas meleagridis/Turkey/Austria/2922-C6/04 using birds of both sexes at various ages. All study groups consisted of 14 birds, of which 10 birds were directly infected via the cloacal route and four birds were kept as in-contact birds. This scheme was used to investigate the pathogenicity of the cloned isolate in 1-day-old and 14-day-old turkeys. In 8-week-old turkeys, only eight birds out of 12 were infected. When 1-day-old and 8-week-old turkeys were infected with 10(4) histomonads per bird, all turkeys died between 11 and 21 days postinfection or had to be euthanatized due to their poor condition. In a group of 14 poults, infective doses of either 10 histomonads (100 histomonads among 10 birds) or 10(3) histomonads per bird had hardly any influence on the first notification of clinical signs. However, even though the onset of clinical signs and mortality was delayed with the lower dose, none of the birds survived the infection. As a consequence, no differences were noticed between male and female turkeys using the mono-eukaryotic culture of Histomonas meleagrigis/Turkey/Austria/2922-C6/04 in the current experimental setting. 相似文献
12.
Sachin Kumar Flavia Militino Dias Baibaswata Nayak Peter L. Collins Siba K. Samal 《Veterinary research》2010,41(5)
Avian paramyxoviruses (APMV) are divided into nine serotypes. Newcastle disease virus (APMV-1) is the most extensively characterized, while relatively little information is available for the other APMV serotypes. In the present study, we examined the pathogenicity of two divergent strains of APMV-3, Netherlands and Wisconsin, in (i) 9-day-old embryonated chicken eggs, (ii) 1-day-old specific pathogen free (SPF) chicks and turkeys, and (iii) 2-week-old SPF chickens and turkeys. The mean death time in 9-day-old embryonated chicken eggs was 112 h for APMV-3 strain Netherlands and > 168 h for strain Wisconsin. The intracerebral pathogenicity index in 1-day-old chicks for strain Netherlands was 0.39 and for strain Wisconsin was zero. Thus, both strains are lentogenic. Both the strains replicated well in brain tissue when inoculated intracerebrally in 1-day-old SPF chicks, but without causing death. Mild respiratory disease signs were observed in 1-day-old chickens and turkeys when inoculated through oculonasal route with either strain. There were no overt signs of illness in 2-weeks-old chickens and turkeys by either strain, although all the birds seroconverted after infection. The viruses were isolated predominantly from brain, lungs, spleens, trachea, pancreas and kidney. Immunohistochemistry studies also showed the presence of large amount of viral antigens in both epithelial and sub-epithelial lining of respiratory and alimentary tracts. Our result suggests systemic spread of APMV-3 even though the viral fusion glycoprotein does not contain the canonical furin proteases cleavage site. Furthermore, there was little or no disease despite systemic viral spread and abundant viral replication in all the tissues tested. 相似文献
13.
Thirty young white storks (Ciconia ciconia) and black storks (Ciconia nigra) from a stork restocking station in Switzerland suffered from cutaneous, verrucous pox-efflorescences on legs, feet, beak and eyelids. The poxvirus was demonstrated ultrastructurally. As the endemic was in autumn, mosquitos may be a possible vector. It is uncertain, if the disease is connected with the previously imported storks from the Federal Republic of Germany. 相似文献
14.
Young chickens, ducks, and turkeys were exposed to sunlight and fed various amounts of Ammi visnaga seeds for 14 days in an attempt to induce photosensitization. In chickens, seeds at 1.25% in the diet had no effect whereas 3% induced mild signs of photosensitization within 6 to 8 days. No visible effects resulted in ducklings from 1.5, 3 and 6% in the diet, or in turkey poults from 3%. These differences appear to be due to differences between these avian species in the metabolism of the photodynamic agent. 相似文献
15.
1. Control by competitive exclusion of intestinal colonisation by Salmonella infantis was studied in domestic chicks and turkey poults given a commercial product developed for use with chickens, compared with two similar preparations containing intestinal microorganisms from turkeys. 2. Each type of material protected both avian species when given orally before challenge; the degree of protection depended at least as much on the type of preparation as its host origin. 相似文献
16.
A series of trials was conducted in which specific-pathogen-free (SPF) leghorn chicks were exposed to various isolates of Alcaligenes faecalis. Chicks were inoculated with A. faecalis alone or in combination with Newcastle disease/infectious bronchitis (Nc/Br) vaccine, laryngotracheitis vaccine, infectious bursal disease virus, or Mycoplasma gallisepticum. The response was evaluated by morbidity, mortality, airsacculitis, reisolation of A. faecalis, and histopathological lesions of tracheas. Although A. faecalis was recovered up to 42 days postinoculation in some cases, no clinical signs were directly attributed to simple A. faecalis infection. None of the other agents significantly increased the severity of A. faecalis signs or lesions, except that A. faecalis-infected chicks that were given Nc/Br vaccine had prolonged microscopic tracheal lesions. In another trial, the effects of A. faecalis in young SPF leghorns, non-SPF broilers, and turkeys were compared. Broiler-type chicks were more susceptible than leghorns and less susceptible than poults. Consequently, the use of leghorns as a model for studying this infection is questioned. 相似文献
17.
Developmental stages of Cryptosporidium baileyi were observed on the conjunctival epithelium of 3 of 14 chicks and none of 7 turkeys following ocular inoculation of oocysts. No clinical signs of disease were observed in chicks or turkeys. All 14 chicks had developmental stages of C. baileyi in the cloaca, whereas 4 of the 7 turkeys were infected at this site. 相似文献
18.
Intestinal and bursal cryptosporidiosis in turkeys following inoculation with Cryptosporidium sp. isolated from commercial poults 总被引：1，自引：0，他引：1
Cryptosporidium meleagridis oocysts, originally isolated from droppings of commercial turkey poults with increased mortality due to viral (reovirus) hepatitis and enteritis, were treated with peracetic acid to kill companion bacteria and viruses and then propagated by passage in young turkeys. Thirty-eight 5-day-old large white turkey poults were inoculated by crop gavage with 500,000 cryptosporidial oocysts and compared with 40 uninoculated poults. Cryptosporidial oocysts shedding began 3 days postinoculation (PI), peaked on day 4 PI, and persisted at a low level for the duration of the 21-day trial. Low to moderate cryptosporidial infections of the ileal mucosa (days 3, 6, and 15 PI), cecal mucosa (days 3, 6, and 21 PI), and bursa of Fabricius (days 6, 12, 15 and 21 PI) were found on histopathological examination. There were no differences in mean body weights between the inoculated and uninoculated groups, and no mortality or clinical signs of disease were seen in either group. 相似文献
19.
Kapczynski DR 《Avian diseases》2004,48(2):332-343
An avian metapneumovirus (aMPV) virosome vaccine was prepared and tested for protection of turkeys by aMPV challenge. The vaccine was produced using a detergent-based (Triton X-100) extraction of aMPV subtype C followed by detergent removal with SM2 Bio-Beads. Western blot and virus-neutralization analysis confirmed that the aMPV virosomes contained both the fusion and attachment glycoproteins. Specific-pathogen-free turkeys were immunized either intranasally (i.n.) or intramuscularly (i.m.) with two doses of the aMPV virosome vaccine. Vaccination decreased clinical signs of disease following virulent challenge, and IN vaccination was superior to i.m. vaccination in reducing clinical signs. Decreases in viral load in the respiratory tract were observed in turkeys receiving i.n. vaccination with aMPV virosomes compared to unvaccinated poults. Increased virus-neutralizing antibody levels against aMPV were observed in birds vaccinated with virosomes. These results demonstrate that immunization of turkeys with aMPV virosomes can be an effective strategy for control of disease. 相似文献
20.
The pathogenicity of serotype 2 OH strain of infectious bursal disease virus (IBDV) to specific-pathogen-free (SPF) chicken embryos and 2-wk-old SPF chickens and turkey poults was investigated. The virus was pathogenic for chicken embryos after five passages as evidenced by pathologic changes in inoculated embryos. The embryo-adapted virus was not pathogenic for 2-wk-old SPF chickens and turkey poults as indicated by lack of clinical signs, gross or microscopic lesions in the bursa of Fabricius of inoculated birds. Bursa-to-body-weight ratios of the inoculated chickens and turkey poults were not significantly different from those of uninoculated controls. Virus-neutralizing antibodies to serotype 2 IBDV were detected in inoculated chickens and turkeys. Results of this study indicated that the embryo-adapted serotype 2 OH IBDV isolate that is pathogenic for chicken embryos is infectious but not pathogenic in chickens and turkeys. 相似文献