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1.
Hydropericardium syndrome, an emerging disease of poultry, has recently been detected in some countries of Asia and America, particularly in broiler birds aged 3–6 weeks. The disease is characterized by its sudden occurrence with high mortality of up to 80% in broilers and low mortality of under 10% in layers, associated with hydropericardium. Its course is of 7–15 days under natural conditions. The causative agent is probably fowl adenovirus serotype 4, belonging to group I aviadenovirus genus of the family adenoviridae, which can be cultivated in primary cell cultures of chicken kidney and embryo liver cells. The transmission of disease occurs laterally by the oral–faecal route. The livers of affected birds show necrotic foci, and basophilic intranuclear inclusion bodies fill the entire enlarged nucleus of some of the hepatocytes. The disease can be diagnosed from its gross lesions, histopathological changes in the liver and by serological tests, such as agar gel diffusion, counter immunoelectrophoresis, indirect haemagglutination and ELISA. It has been brought under control by inactivated liver organ vaccines (0.25 ml/bird) or inactivated cell culture vaccines (103.5 LD50/bird) given by the subcutaneous route at 10–15 days of age. The vaccine is effective in the face of an outbreak and significantly reduces the mortality.  相似文献   

2.
Four sporadic cases of congenital swinepox are described. The pigs were born with pox lesions over their entire bodies. Microscopic examination revealed ballooning degeneration of keratinocytes, cytoplasmic inclusions and intranuclear vacuolisation. Electron microscopy detected poxvirus particles in all four pigs. The virus was isolated from one pig and identified by HindIII restriction endonuclease digestion as swinepox virus.  相似文献   

3.
Gross and microscopic lesions of experimental simian varicella (Delta herpesvirus) infection in African green monkeys (Cercopithecus aethiops) are described. In stratified squamous epithelium, such as the epidermis, tongue, and esophagus, focal areas of epidermal hyperplasia, ballooning degeneration, and blood-filled vesicle formation with ulceration were apparent. Most visceral organs were involved, and the changes included necrosis, hemorrhage, and characteristic intranuclear eosinophilic inclusions in a variety of cells. A generalized vascular involvement was present with intranuclear inclusions in the endothelial and smooth muscle cells in various organs. The nervous system was normal on gross and microscopic examination. Virus titer and serum transferase values were correlated with the clinical signs of infection.  相似文献   

4.
Eight 1-yr-old common pintails (Anas acuta acuta) and one 2-yr-old white-faced whistling duck (Dendrocygna viduata) were presented for the persistence of primary flight feathers 1 yr after pinioning. The birds were housed outdoors in an open enclosure necessitating flight prevention. The birds were placed under general anesthesia, and a diode laser was used to ablate the primary feather follicles of the previously pinioned wing. Swelling was the most common side effect seen in seven out of nine treated birds. Other side effects included ulceration, hyperemia, edema, and serosanguinous discharge. All side effects were resolved by 12 wk postprocedure. Laser feather follicle ablation was successful in 28 of 40 (70%) of the treated common pintail feathers, and flight was not observed 7 mo following the procedure in any of these birds. Feather follicle ablation was successful in two of six (33%) of the treated white-faced whistling duck feathers, and the bird in question was observed flying 5 mo after the procedure. Primary feather follicle ablation with a diode laser was a successful method of flight prevention in common pintails but was not effective for a white-faced whistling duck.  相似文献   

5.
Canary pox causing high mortality in an aviary   总被引:1,自引:0,他引:1  
In an aviary housing 200 six-month-old canaries, 165 became ill and 145 died over a 6-week period from a disease initially characterized by lethargy, ruffled feathers, open-mouth breathing, and death in 2 to 3 days. Proliferative "pox-like" lesions around the eyes and mouth were not seen until the 4th week. At necropsy, initially affected birds had cloudy air sacs and patchy pneumonia. Histologically, the lungs had proliferative necrotizing bronchitis. Birds necropsied later had proliferative skin lesions and intracytoplasmic inclusions typical of poxvirus in the epidermis and airway epithelium. A virus was isolated from an organ pool of lung, air sac, liver, and skin of affected birds and was identified by electron microscopy as poxvirus.  相似文献   

6.
Seven 19-day-old broiler chickens affected with hydropericardium syndrome (HPS) with pancreatic necrosis and gizzard erosions were investigated pathologically and virologically. Mortality increased after 13 days of age in a flock on a broiler farm. The mortality rate of the flock reached 10% by 19 days of age. Macroscopically, the chickens had hydropericardium (the characteristic gross change of HPS), pinpoint white foci in the pancreas, and ventricular erosions. Histologically, the chickens had multifocal hepatic necrosis with intranuclear inclusions in hepatocytes, a marked increase of macrophages in the spleen and lung, mild epicardial edema, multifocal necrosis of pancreatic acinar cells with intranuclear inclusions, focal necrosis of the ventricular koilin layer, and degeneration of the ventricular glandular epithelium with intranuclear inclusions. Immunohistochemically, intranuclear inclusions in the liver, pancreas, and ventriculi were stained positively against group I avian adenovirus (GIAAV) antigens. Ultrastructurally, 67-nm diameter viral particles were present in intranuclear inclusions. Virologically, serotype 4 of GIAAV was isolated from the liver, heart, and kidney of affected chickens. The pathologic changes of the present cases differ from previous cases of HPS; therefore, the present strain of GIAAV may have different pathogenicity for chickens than the previous virus strain of HPS.  相似文献   

7.
Recent discoveries of feathered dinosaurs from Early Cretaceous deposits in Liaoning, China, have not only lent strongest support for the dinosaurian hypothesis of bird origins, but have also provided much‐needed information about the origins of feathers and avian flight. Preliminary analysis of character evolution suggests that the major avian osteological characters were acquired during the early evolution of maniraptoran dinosaurs. The available evidence also suggests that the first feathers with a filamentous morphology probably evolved in basal coelurosaurs and pennaceous feathers (including those with aerodynamic features) were developed in non‐avian maniraptorans, indicating that feathers evolved before the origin of birds and their flight. An evolutionary model is proposed here to describe the major stages of feather evolution, a process characterized by a combination of both transformational and innovative modifications. This model is different from some recent developmental models, which suggest that feathers are evolutionary novelties without a homologous relationship to reptilian scales. Although non‐avian theropods are traditionally regarded as distinctly cursorial animals, recent discoveries suggest that the closest relatives of birds might be arboreal theropods. Many bird features, such as the furcula and pennaceous feathers, evolved in a terrestrial context, whereas others, such as some pedal modifications, may have evolved in an arboreal context. Consequently, arboreality may have also contributed to the origin of avian flight.  相似文献   

8.
The progress and transmission of blackhead disease in chickens was studied in battery cages and floor pens in the absence of vectors. Two-week-old chicks were inoculated intracloacally with Histomonas meleagridis and allowed to commingle with others in floor pens. There was no confirmed transmission of blackhead to other birds in the pen, whether stocked at 10% or 25% with infected birds. A second experiment evaluated the effects of feed restriction of chickens on spread of blackhead within floor pens. Inoculated seeder birds had severe cecal lesions of blackhead at necropsy, regardless of feed restriction. Uninoculated birds did not develop lesions by the time of necropsy at 42 days of age, regardless of whether full-fed or limited by skip-day feeding. Chickens inoculated intracloacally with H. meleagridis and placed in battery cages became infected and had cecal lesions of blackhead, but few liver lesions. Chickens allowed to commingle with the inoculated birds in batteries had no lesions of histomoniasis at necropsy 2 wk postinoculation. Coccidial oocysts from turkeys (Eimeria adenoeides) were inoculated along with H. meleagridis from cultures to test the effects of sporozoite penetration in the ceca on progress of blackhead disease. Histomoniasis was not worsened by the interaction with sporozoites, as shown by unchanged severity of cecal lesions, the number of birds showing liver lesions, or the overall number of positive birds. Overall, blackhead infections showed no inclination to spread from bird to bird under conditions of these studies, in contrast to what has been reported for turkeys. These results suggest that the dynamics of blackhead transmission in chickens differs significantly from that of turkeys, where transmission from bird to bird is rapid and effective in the absence of vectors.  相似文献   

9.
黑鹳在人工饲养条件下的繁殖   总被引:2,自引:0,他引:2  
1985年-1993年对黑鹳先后组成4对配偶,共产卵32枚,受精卵14枚,受精率43.75%,出雏8只,出雏率57.4%,成活5只,成活率62.5%。黑雏在笼养条件下,3岁龄性成熟。齐齐哈尔地区4-6月份产卵,一般窝产卵4枚,年最多产卵16枚,孵化期31天。黑鹳为晚成鸟。自然育雏在雏鸟出壳后3-4小时开食,人工育雏24小时开食,15日龄雏鸟开始生长初级飞羽羽鞘,20-25日龄能站立,30-35日龄  相似文献   

10.
CASE HISTORY: Nine of 24 captive kiwi treated with oral levamisole at a dose between 25–43 mg/kg showed signs of respiratory distress. Six died within 4 h of treatment and the remaining three made a full recovery within 24 h.

CLINICAL AND PATHOLOGICAL FINDINGS: Within 3–4 h of treatment, the affected birds had an elevated respiratory rate, mucoid nasal discharge and rapidly became comatose. Post mortem examination revealed accumulation of thick mucus in the oral cavity and trachea. There was severe pulmonary congestion and oedema and early bronchopneumonia in the lungs of five of the birds. In two birds, there was acute hepatic degeneration and necrosis and one bird had acute pancreatic degeneration and necrosis.

DIAGNOSIS: Acute levamisole toxicity.

CLINICAL RELEVANCE: Kiwi were acutely sensitive to levamisole toxicity at doses that are well within the safe range for domestic poultry. Levamisole should not be used as an anthelmintic in kiwi.  相似文献   

11.
Parvovirus-like enteropathy in Missouri turkeys   总被引:1,自引:0,他引:1  
A viral enteric disease of young turkeys characterized by stunting of affected birds, diarrhea, and increased mortality is described. Eosinophilic intranuclear inclusion bodies were found in the absorptive epithelial cells of the ileum. Electron microscopy of formalin-fixed tissue revealed that the intestinal inclusions contained numerous loosely packed 15-to 20-nm hexagonal particles. The size, shape, and intranuclear location have been used to tentatively identify these particles as parvoviruses.  相似文献   

12.
Hu J  McDougald LR 《Avian diseases》2003,47(2):489-492
The lateral transmission of Histomonas meleagridis in turkeys was studied in floor pens without the presence of Heterakis gallinarum. Battery-reared poults (120) were transferred at 2 wk of age to concrete-floored floor pens with fresh pine shavings litter (40/group). One group received no exposure. In other groups, either 10% or 25% of the birds were inoculated per cloaca with cultured H. meleagridis (200,000/bird) and placed in the pens as seeder birds. Inoculated birds died at 10-18 days postinfection (PI) showing typical liver and cecal lesions of histomoniasis. Birds in the high-exposure group died of histomoniasis beginning 16 days PI and continuing to 100% mortality by day 23 PI. Birds in the low-exposure (LE) group died beginning on day 19 PI and continuing through day 31 PI. All but one LE bird alive on day 31 PI had severe liver and cecal lesions of histomoniasis at necropsy. There was no evidence of histomoniasis in unexposed birds. No cecal worms (H. gallinarum) were found at necropsy of dead birds or in unexposed birds at the end of the experiment. Even though H. gallinarum is the only known reservoir for H. meleagridis, these results suggest that lateral transmission of histomoniasis through a flock can occur readily through normal contact between uninfected birds and infected birds and their droppings in the total absence of cecal worms.  相似文献   

13.
The spread of Histomonas meleagridis infections through groups of turkeys in the absence of the cecal worm vector (Heterakis gallinarum) was studied in a battery cage model. Battery-reared poults were exposed at 2 wk of age by commingling with infected birds into cages that had the floor lined with paper. One treatment received no exposure, whereas other birds were commingled with two, three, or four birds/cage (25%, 37.5%, or 50%) inoculated per cloaca with cultured H. meleagridis (200,000/bird). Inoculated birds died at 7-13 days postinoculation (DPI) showing typical liver and cecal lesions of histomoniasis. By 14 DPI, 87.5% of the directly inoculated birds died or had severe lesions of histomoniasis. Turkeys commingled with two, three, or four infected birds became infected at the rate of 72%, 80%, or 75%, respectively. In another experiment, two birds/cage (25%) were inoculated with Histomonas from culture and allowed to commingle with other birds for 1, 2, 3, or 4 days. Two of 12 (16.7%) birds had minor cecal lesions after contact with inoculated birds for 1 day, but 87.5%-100% became infected if inoculated birds remained in the cage for 2-4 days. Contemporaneous inoculation with cecal coccidia (Eimeria adenoeides) as a predisposing factor in blackhead infections was studied using the model. Turkey poults directly inoculated with Histomonas were allowed to commingle for 5 days with uninoculated birds that had received inoculation with 0, 10(3), or 10(4) sporulated oocysts. The coccidian infection appeared to interfere with transmission of blackhead infection by 7 DPI, as suggested by lessened severity of cecal lesions and a lower percentage of infected birds. These studies confirm that histomoniasis is transmitted readily from directly exposed young turkeys to others in the absence of the cecal worm vector, and that this phenomenon can be reproduced in battery cages as an experimental model.  相似文献   

14.
This paper concerns a disease affecting a group of African grey parrots, which involves intranuclear inclusion bodies composed of filamentous material. The disease was characterized by either sudden death or death within 2–3 days from onset of non-specific symptoms. At necropsy, gross lesions included enlarged liver, mild hepatic congestion and focal necrosis. Samples from five birds were fixed in 10% formol and routinely processed for light and electron microscopy. In four birds, numerous hepatocytes displayed an enlarged nucleus, with peripheral margination of chromatin; the nucleus was partially or wholly filled by a basophilic inclusion body. In the remaining bird, inclusion bodies were acidophilic and completely filled the nucleus; nuclear enlargement was less evident than in the other birds. At ultrastructural examination, and in both types of IIB, nuclei contained looped filaments but no evidence of viral structures. However, virion-like structures were observed in the cytoplasm of some hepatocytes.  相似文献   

15.
One-day-old, 2-wk-old, and 4-wk-old call ducks (Anas platyrhyncha var. domestica) inoculated intravenously with the H5N1 highly pathogenic avian influenza virus A/chicken/Yamaguchi/7/2004 isolate (Ck/Yama/7/04) were examined clinically, pathologically, and virologically. Clinically, the birds exhibited mild-to-severe neurologic signs and corneal opacity. All birds in the 1-day-old group and one bird in the 4-wk-old group died within 4 days after the virus inoculation. Histologic changes were characterized by severe nonpurulent encephalitis and necrotic lesions of feather epithelium on day 3 postinoculation (PI) or later. Focal necrosis of myocardial cells, pancreatic acinar cells, skeletal myocytes, and corneal epithelial cells was observed. Viral antigens were detected in association with necrotic changes. Viruses were isolated from all examined organs including the skin with many feathers. Serum antibody against the virus was detected in all surviving birds on day 10 PI by hemagglutination-inhibition tests. These results suggest that Ck/Yama/7/04 has a pathogenicity that causes neurologic sign, nonpurulent encephalitis with mortality, and feather lesions for call ducks. Feather lesions with viral antigens and the virus isolation from the skin suggest that Ck/Yama/ 7/04 has a predilection for feathers in call ducks.  相似文献   

16.
This paper concerns a disease affecting a group of African grey parrots, which involves intranuclear inclusion bodies composed of filamentous material. The disease was characterized by either sudden death or death within 2-3 days from onset of non-specific symptoms. At necropsy, gross lesions included enlarged liver, mild hepatic congestion and focal necrosis. Samples from five birds were fixed in 10% formol and routinely processed for light and electron microscopy. In four birds, numerous hepatocytes displayed an enlarged nucleus, with peripheral margination of chromatin; the nucleus was partially or wholly filled by a basophilic inclusion body. In the remaining bird, inclusion bodies were acidophilic and completely filled the nucleus; nuclear enlargement was less evident than in the other birds. At ultrastructural examination, and in both types of IIB, nuclei contained looped filaments but no evidence of viral structures. However, virion-like structures were observed in the cytoplasm of some hepatocytes.  相似文献   

17.
Seventy-two 13-week-old ring-necked pheasants were inoculated orally with 5.0 x 10(2) tissue-culture infective dose (TCID) of cell-culture-propagated marble spleen disease virus. Inoculated birds exhibited neither mortality nor clinical disease. Gross and histologic lesions were typical of marble spleen disease. The mean splenic weight was significantly (P less than 0.02) higher in inoculated birds than in controls between 6 and 10 days postinoculation (PI). The histologic splenic lesions, which consisted of reticuloendothelial cell hyperplasia, intranuclear inclusions within reticuloendothelial cells, and lymphoid depletion, were most prominent between 6 and 10 days PI. In a second experiment, 1-day-old pheasants were chemically bursectomized by dosing birds with 1.2 mg cyclophosphamide on 3 consecutive days. At 7 weeks of age, 54 bursectomized birds were inoculated orally with 5.0 x 10(2) TCID of marble spleen disease virus. Gross and histologic lesions were detected in one of the inoculated pheasants, but the mean splenic weight was not significantly different from control birds at any time PI. These results are evidence of the role of the bursa of Fabricius in the pathogenesis of marble spleen disease.  相似文献   

18.
The nature of feather inclusions was characterized in 32 psittacine birds (30 cockatoos, one peach-faced lovebird (Agapornis roseicollis), and one red-lored Amazon parrot (Amazona autumnalis autumnalis] with naturally-acquired psittacine beak and feather disease. Intranuclear inclusions within feather epithelial cells and intracytoplasmic inclusions within macrophages in the feather epithelium and pulp cavity contained psittacine beak and feather disease viral antigen when stained by the avidin-biotin complex immunoperoxidase technique. Ultrastructurally, inclusions were observed primarily within macrophages and to a lesser extent within epithelial cell nuclei. Macrophage inclusions appeared as paracrystalline arrays of viral particles. Intranuclear inclusions were less well defined, although scattered viral particles were present. Intracytoplasmic and intranuclear particles in ultrastructural preparations were identified by colloidal gold labeling as psittacine beak and feather disease virus. Feather epithelium was more frequently and severely involved in the disease process than was adjacent follicular epithelium. Plucked feathers with an intact epidermal collar and feather epithelium were preferred to follicular biopsies for histopathologic examination.  相似文献   

19.
The pathogenicity of serotype 1 group I avian adenovirus (GIAAV) strains isolated from gizzard erosions for 1-wk-old specific-pathogen-free (SPF) chickens was investigated. In Experiment 1, SPF chickens inoculated orally with a serotype 1 strain (Tokushima2000/GE) of GIAAV isolated from gizzard erosion in broilers were euthanatized and necropsied from 3 to 12 days after inoculation. Clinically, there were no significant signs in the chickens inoculated with Tokushima strain. The gizzards were found macroscopically to be dilated with liquefied contents. The koilin layer of the gizzard exhibited multifocal white lesions with occasional erosions. Gross lesions of the koilin layer (white foci and erosion) appeared at 3 days after inoculation and persisted until 12 days after inoculation. The gross lesions were most severe at 9 days after inoculation. Histologically, multifocal degeneration, necrosis, and loss of the glandular epithelial cells with intranuclear inclusions, liquefactive change of koilin substance, and erosive lesions of koilin layers and surface epithelium of the gizzards were observed. Macrophages increased in the focal areas of the lamina propriabelow the liquefactive koilin substances. Immunohistochemically, intranudear inclusions were positive against GIAAV antigen. Histologic lesions of gizzards were most severe at 7 and 9 days after inoculation, but the frequency of intranuclear inclusions was greatest at 5 days after inoculation. In Experiment 2, the pathogenicities of four strains of serotype 1 GIAAV for 1-wk-old SPF chickens were compared. Three strains isolated from gizzard erosion had similar pathogenicities but one strain from a normal chicken was not pathogenic for chickens. These results suggest that gizzard erosions by serotype 1 GIAAV infection may occur in broiler chickens in Japan.  相似文献   

20.
1. A flock of laying hens was divided into two groups according to their fatness, which was estimated using abdominal fatness callipers.

2. A moult was induced in both groups by reducing day‐length and restricting food intake. The food restriction period lasted for 2, 3 or 4 weeks and the birds were given either 15 or 25 g of whole wheat/bird.

3. No differences were observed between the moulting treatments on post‐moult egg weights, shell strength or Haugh units, but maximum egg output (g/bird d) was obtained by the 4‐week food restriction period for the fat‐grouped birds but by the 3‐week food restriction for the lean‐grouped birds.

4. The birds restricted to 15 g wheat/bird d showed a more rapid regression of the ovary and oviduct, which may account for their increased egg numbers towards the end of the 22‐week laying period compared to the birds allocated 25 g/bird d.  相似文献   


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