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1.
Isospora michaelbakeri is one of the Isospora species most commonly found in the wild field, which can cause severe infection and mortality in young sparrows. In this study, we selected I. michaelbakeri (Chung Hsing strain) as a pathogen to orally inoculate russet sparrows (Passer rutilans), spotted munia (Lonchura punctulata), canary (Serinus canaria), Java sparrows (Padda oryzivora), chicken (Gallus domesticus), ducks (Anas platyrhynchos) and BALB/c mice. The results indicated that I. michaelbakeri infected only russet sparrows. Infected sparrows displayed lethargy, muscular weakness and fluffy feathers, followed by rapid death. Liver and spleen enlargement was seen in the infected birds. Schizonts were identified in thin smears from the venous blood, enlarged livers and spleens. Histopathological examination revealed schizonts and merozoites from the liver and spleen of infected russet sparrows, but not from other species experimentally inoculated with I. michaelbakeri in the present study.  相似文献   

2.
本文记述寄生于红嘴相思鸟[Leiothrixlutea(scopoli)]肌胃的一线虫新种。新种特征:缺侧翼,具粗大环纹,雄虫尾部腹面复盖盾片和大小相等的尾翼,尾乳突排列对称且肛后乳突特大,引带铲形,有别于其他种。  相似文献   

3.
The anthelmintic efficacy of ivermectin (administered subcutaneously at 200 micrograms kg-1 body weight) was assessed for control of Thelazia skrjabini in experimentally infected calves. Twenty-four uninfected male Holstein calves, 1-2 weeks old, were artificially infected with Thelazia skrjabini by placing 15 third-stage larvae under the third eyelid of calves. The challenge larvae were recovered from naturally infected face flies, Musca autumnalis. The exposed calves were randomly assigned to either an ivermectin treatment group or a control group within pairs ranked by weight. Equal numbers of calves were housed in each of four indoor fly-free rooms. The calves were treated with ivermectin or saline 35 days post-infection, then slaughtered 14 days later to determine eyeworm numbers. All eyes and associated tissues (including the lacrimal glands and ducts) were removed and examined for total number, species and viability of eyeworms. Thelazia skrjabini was found in the control group of calves only. The efficacy of ivermectin against Thelazia skrjabini was thus shown to be 100%.  相似文献   

4.
AIM: To investigate the role of free-living animals such as sparrows, rodents and flies as potential reservoirs of Campylobacter spp on a dairy farm, and to assess the genetic diversity among Campylobacter isolates from the farm and an urban source. METHODS: A total of 290 samples (bovine, passerine and rodent faeces, and whole flies) were collected from a large commercial dairy farm in the Manawatu district in New Zealand, and from faeces from urban sparrows in a nearby city. Other samples collected from the dairy farm included five from silage, two from aprons worn by workers during milking, two from workers' boots and two from water in troughs in a paddock. Isolates of thermophilic Campylobacter spp were identified morphologically and phenotypically and further characterised molecularly using pulsed-field gel electrophoresis (PFGE) and the restriction enzyme SmaI. RESULTS: Campylobacter jejuni was the only Campylobacter species isolated from all samples. The highest prevalence was found in faeces from dairy cows (54%), followed by faeces from sparrows from the urban area (40%) and the farm (38%), and from rodents (11%) and whole flies (9%). Other samples from the farm environment such as silage, trough water, and workers' aprons and boots were also positive for C. jejuni. Of the 22 restriction patterns obtained, seven were common to more than one source. CONCLUSIONS: Cattle, sparrows, rodents and flies are potential reservoirs of C. jejuni on dairy farms. Identical clones of C. jejuni carried by cattle, sparrows, flies and rodents probably indicate a common source of infection. The high level of asymptomatic carriage of C. jejuni by healthy dairy cows could be sufficient to maintain infections within the dairy farm surroundings via environmental contamination.  相似文献   

5.
AIM: To investigate the role of free-living animals such as spar- rows, rodents and flies as potential reservoirs of Campylobacter spp on a dairy farm, and to assess the genetic diversity among Campylobacter isolates from the farm and an urban source.

METHODS: A total of 290 samples (bovine, passerine and ro- dent faeces, and whole flies) were collected from a large com- mercial dairy farm in the Manawatu district in New Zealand, and from faeces from urban sparrows in a nearby city. Other samples collected from the dairy farm included five from silage, two from aprons worn by workers during milking, two from workers' boots and two from water in troughs in a paddock. Isolates of thermophilic Campylobacter spp were identified mor- phologically and phenotypically and further characterised mo- lecularly using pulsed-field gel electrophoresis (PFGE) and the restriction enzyme SmaI.

RESULTS: Campylobacter jejuni was the only Campylobacter species isolated from all samples. The highest prevalence was found in faeces from dairy cows (54%), followed by faeces from sparrows from the urban area (40%) and the farm (38%), and from rodents (11%) and whole flies (9%). Other samples from the farm environment such as silage, trough water, and work- ers' aprons and boots were also positive for C. jejuni. Of the 22 restriction patterns obtained, seven were common to more than one source.

CONCLUSIONS: Cattle, sparrows, rodents and flies are po- tential reservoirs of C. jejuni on dairy farms. Identical clones of C. jejuni carried by cattle, sparrows, flies and rodents prob- ably indicate a common source of infection. The high level of asymptomatic carriage of C. jejuni by healthy dairy cows could be sufficient to maintain infections within the dairy farm sur- roundings via environmental contamination.  相似文献   

6.
为研究斯氏副柔线虫(Parabronema skrjabini)种间遗传标记特点,从内蒙古地区骆驼皱胃中采集斯氏副柔线虫成虫,提取虫体DNA,利用线虫通用引物扩增细胞色素氧化酶1(CO1)基因,将其克隆到pMD19-T载体后,用PCR技术鉴定阳性菌落并进行测序,运用DNAStar 5.0和MEGA 4.0软件将测序结果与GenBank公布的相关线虫CO1序列进行比对分析。结果显示:斯氏副柔线虫DNA扩增出的CO1基因序列片段长度为689 bp。同其他相关属线虫CO1基因序列比对,斯氏副柔线虫与小口柔线虫(Habronema microstoma)、蝇柔线虫(Habronema muscae)的同源性最高,为86.7%,遗传距离为0.143;与加利西亚光丝虫(Litomosoides galizai)的同源性最低,为80.1%,遗传距离为0.229。通过两种不同方法建立的系统发育树比较,证实斯氏副柔线虫与柔线属线虫均位于同一分支,自展值都在47%以上。表明CO1基因不仅可以作为斯氏副柔线虫理想的种间遗传标记,也可为该线虫进一步的分子分类学研究提供重要基础。  相似文献   

7.
福建省并殖吸虫虫种及其地理分布   总被引:6,自引:0,他引:6  
为了调查福建省并殖吸虫虫种及其地理分布 ,捕捉、收集各地溪蟹 ,分离各种并殖吸虫囊蚴感染猫、狗或鼠、兔 ,检获成虫鉴定虫种。结果发现福建省共有 7种虫种 ,即 :林氏并殖吸虫、卫氏并殖吸虫、斯氏并殖吸虫、三平正并殖吸虫、福建并殖吸虫、闽清并殖吸虫和泡囊并殖吸虫 ,分布于全省 42个县 ,其中卫氏并殖吸虫为广泛分布的优势虫种  相似文献   

8.
This investigation assessed the ability of the zoonotic A/chicken/Hong Kong/220/97 (chicken/Hong Kong) (H5N1) highly pathogenic avian influenza virus to infect and cause disease in zebra finches (Taeniopygia guttata), house finches (Carpodacus mexicanus), house sparrows (Passer domesticus), European starlings (Sternus vulgaris), and budgerigars (Melopsittacus undulatus) after intranasal administration. Zebra finches were the most severely affected of the five species, demonstrating anorexia, depression, and 100% mortality within 5 days of inoculation. Gross lesions in this species were absent or only mild. But histologic lesions and the corresponding viral antigen were observed in multiple organs, especially in the nasal cavity, brain, pancreas, spleen, adrenal glands, and ovary. Significant morbidity and mortality also were observed in both house finches and budgerigars. Affected birds of these two species demonstrated anorexia, depression, and neurologic signs and typically were moribund or dead within 2 days of the onset of clinical signs. Gross lesions were mild or absent in house finches and budgerigars. Histologically, the brain and pancreas were the most consistently and severely affected organs in house finches. The brain was the most affected organ in budgerigars. Unlike these three species, house sparrows suffered only mild transient depression, had no mortality, and lacked gross lesions. Viral antigen and microscopic lesions were observed only in the heart and testicle of a minority of birds of this species. Starlings demonstrated neither clinical disease nor mortality and lacked gross and histologic lesions. Viral antigen was not observed in any of the collected tissues from starlings. These results indicate that there is significant variation in the pathogenicity of the chicken/Hong Kong virus for different species of birds, including species within the same order. In addition, neurotropism is a recurrent feature among birds that eventually succumb to infection.  相似文献   

9.
Numerous nematode cysts were observed throughout the mesentery and on the surface of gastrointestinal organs in a whooping crane (Grus americana) that was found dead in a central Florida marsh. Morphology of the excysted nematodes most closely resembled third-stage larvae in the order Spirurida but were not similar to any species previously reported in whooping cranes. Evidence presented suggests that the larvae may be Physocephalus sexalatus, a swine spirurid in the subfamily Ascaropsinae that is commonly found encapsulated in birds, amphibians, and reptiles. We suspect that the whooping crane may potentially serve as a transport host for this parasite.  相似文献   

10.
Genetic changes in avian influenza viruses influence their infectivity, virulence and transmission. Recently we identified a novel genotype of H9N2 viruses in widespread circulation in poultry in Pakistan that contained polymerases (PB2, PB1 and PA) and non-structural (NS) gene segments identical to highly pathogenic H7N3 viruses. Here, we investigated the potential of these viruses to cause disease and assessed the transmission capability of the virus within and between poultry and wild terrestrial avian species. Groups of broilers, layers, jungle fowl, quail, sparrows or crows were infected with a representative strain (A/chicken/UDL-01/08) of this H9N2 virus and then mixed with naïve birds of the same breed or species, or different species to examine transmission. With the exception of crows, all directly inoculated and contact birds showed clinical signs, varying in severity with quail showing the most pronounced clinical signs. Virus shedding was detected in all infected birds, with quail showing the greatest levels of virus secretion, but only very low levels of virus were found in directly infected crow samples. Efficient virus intra-species transmission was observed within each group with the exception of crows in which no evidence of transmission was seen. Interspecies transmission was examined between chickens and sparrows and vice versa and efficient transmission was seen in either direction. These results highlight the ease of spread of this group of H9N2 viruses between domesticated poultry and sparrows and show that sparrows need to be considered as a high risk species for transmitting H9N2 viruses between premises.  相似文献   

11.
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   

12.
In the present study day-old specific-pathogen-free (SPF) and commercial broilers with maternally derived fowl adenovirus serotype 1 (FAdV-1) antibodies were orally infected with a European “pathogenic” FAdV-1, isolated from broilers showing signs of gizzard erosion. During the experiment, broilers were observed and weighed daily up to 17 days post infection (dpi). Clinically, both infected groups showed significant decrease of weight compared to respective negative control groups. Birds were examined by necropsy at 3, 7, 10, 14 and 17 dpi. Pathological changes in the gizzards were noticed in both experimentally infected groups from 7 dpi onwards. Macroscopically, erosion of the koilin layer and inflammation or ulceration of the gizzard mucosa were observed. Histologically, presence of FAdV-1 in intranuclear inclusion bodies of degenerated glandular epithelial cells was demonstrated by in-situ hybridization and inflammatory cell infiltration of the lamina propria, submucosa and muscle layer was detected. Tissue samples were investigated by a recently developed real-time PCR and the viral DNA load was calculated from gizzard, liver, spleen and cloacal swabs with the highest amounts of FAdV-1 DNA found in the gizzard. For the first time, successful reproduction of clinical signs in broilers as well as pathological lesions in the gizzard were achieved with a European FAdV-1 isolate displaying some genetic differences to so far reported virulent FAdV-1 from Japan. Furthermore, highest viral load in gizzards could be linked with macroscopical and histological lesions. Therefore, the conducted analyses provide important insights into the pathogenesis of adenoviral gizzard erosion.  相似文献   

13.
Thelazia anolabiata is a spirurid nematode living in the orbits of birds which can cause lacrimation, keratitis, conjunctivitis, and corneal ulcers. This species is reported for the first time from an Andean Cock of the Rock, Rupicola peruviana (Passeriformes: Cotingidae), from a zoo in Lima, Peru. Clinical signs of keratoconjunctivitis were resolved with the treatment of ivermectin, ciprofloxacin, and an epithelium regenerator, and the host is presently in good health. The nematodes were identified using the primary characteristics used to differentiate the species of this genus as lengths of spicules and other morphologic characteristics.  相似文献   

14.
Pooled faeces collected from a garden bird table were screened for Salmonella species and Escherichia coli O86, two recognised causes of garden bird mortality. Dead birds found at the site were also screened for these organisms, and bird numbers and meteorological data were recorded. In the first year of the study, 48.5 per cent of the samples were positive for Salmonella Typhimurium DT56 (variant), decreasing to 38.9 per cent in the second year and 12.8 per cent in the third year. E. coli O86 was not recovered from any of the 288 samples of pooled faeces tested. S. Typhimurium DT56 (variant) was recovered from the carcases of eight birds found dead at the site, and E. coli O86 was isolated from three carcases. The degree of contamination of the bird table with S. Typhimurium DT56 (variant) was positively correlated with the number of house sparrows observed in the garden, but not with the number of blackbirds, chaffinches or greenfinches.  相似文献   

15.
During an epornitic of velogenic viscerotropic Newcastle disease (VVND) in southern California, free-flying wild birds, captive and free-ranging semidomestic birds, and exotic birds were collected from the quarantine area to determine their role in the epizootiology of the disease. The VVND virus was isolated from 0.04% of 9,446 free-flying wild birds, 0.76% of 4,367 semidomestic birds, and 1.01% of 3,780 exotic birds examined. Three house sparrows and 1 crow directly associated with infected poultry flocks were the only free-flying wild birds from which VVND virus was isolated. Among semidomestic species, ducks, quail, chukars, pheasants, peafowl, pigeons, and doves were found to be infected. Psttacines, pittas, and toucans accounted for 92% of the VVND virus isolations from exotic birds. In addition, domestic Newcastle disease virus (NDV) was isolated from 0.29% of the free-flying wild birds, from 1.65% of the semidomestic birds, and from 0.19% of the exotic birds collected. Hemagglutination-inhibition against domestic NDV was demonstrated in 0.24% of 3,796 wild bird serums, 8.28% of 2,004 semidomestic bird serums, and 3.90% of 231 exotic bird serums tested. Although few free-flying wild birds were infected with VVND virus in this epornitic, the isolation of domestic NDV strains from free-flying wild ducks and mourning doves suggests the potential for transportation of NDV over long distances by migratory birds.  相似文献   

16.
Haemosporidian parasites infection among wild birds inhabiting Minami-daito Island was studied. Blood films from 183 birds representing 4 species of 4 families were examined microscopically. Avian haemosporidian parasites were detected in 3 species with an overall prevalence of 59.6%. None of the 30 Daito scops owls (Otus scops interpositus) examined were infected. Either Haemoproteus sp. or Plasmodium sp. infection was found in 14 of 31 (45.2%) Borodino islands white-eyes (Zosterops japonicus daitoensis). Plasmodium spp. were found in 94 of 102 (92.2%) bull-headed shrikes (Lanius bucephalus) and 1 of 20 (5%) tree sparrows (Passer montanus).  相似文献   

17.
NOS-immunoactive nerve structures were studied in the domestic hen (Gallus domesticus) stomach using single-labelling immunofluorescence. The examined tissues were collected from 10-12 months old laying hens (n=11), Isabrown and Zielononózka races. The distribution and number of the nerve fibres was examined considering differences between the proventriculus and gizzard, and also between particular layers of the stomach wall. Large or moderate numbers of nerve fibres showing NOS-immunoreactivity (NOS-IR) were found in all major layers of both parts of the stomach. In the muscular layer of the gizzard, NOS-positive nerve cell bodies were also observed. Small or moderate numbers of nerve terminals were distributed around blood vessels. NOS-IR nerve fibres associated with blood vessels were slightly more numerous in the gizzard than in the proventriculus. The widespread occurrence of NOS in both parts of the hen stomach can prove its important role in the control of digestive processes. It seems that there is a reasonable necessity of further, more detailed studies on morphological characteristics of the nitrergic nerve structures the bird alimentary tract, their functional significance and plasticity in different physiological and pathological conditions.  相似文献   

18.
Salmonella enterica subspecies enterica serotype Typhimurium and Escherchia coli O86:K61:NM are two bacteria that can cause outbreaks of mortality in garden birds visiting bird tables and other feeding stations. Two sites in south-west Scotland were monitored for the two organisms for 12 months. At site A, large numbers of birds fed throughout the year, and at site B smaller numbers of birds fed only in the winter months. Samples of composite faeces were collected from the feeding stations and screened for the organisms, and any dead birds were also screened. S Typhimurium definitive type (DT) 56 (variant) was found to be endemic at site A, and was recovered from 48 per cent of samples of composite faeces collected from the bird table, from 42 per cent of composite faeces from underneath a hanging feeder, and from 33 per cent of composite faeces from below a roost used by house sparrows; the organism was also isolated from the carcases of six wild birds found dead at the site. In contrast, S Typhimurium (DT41) was recovered only once at site B, from 2 per cent of the composite faeces from below a hanging feeder, and no dead birds were recovered from the site. E coli O86 was not recovered from the faeces collected from either site, but was isolated from a bird that died from trauma at site A.  相似文献   

19.
Impaction of the gizzard was diagnosed in 33 1-to-4-wk-old lesser rhea (Pterocnemia pennata) raised on farms in Patagonia, Argentina. The birds showed anorexia, lethargy, constipation, dehydration, weight loss, and weakness. Necropsy revealed gizzard impaction by fibrous material, sand, rocks, and rubbish. Also, excess fibrous material was observed in the small intestine, and intussusception was found in one chick. Impaction of the gizzard observed in the present study was similar to that reported in other ratite species and confirmed that this disease can affect lesser rhea chicks raised in captivity. This disease affected 33 out of 41 (80%) dead lesser rhea chicks submitted to the Animal Health Unit of The National Institute of Agricultural Technology, Bariloche, Argentina, during the study period, so it can be a significant cause of mortality in farmed rheas in Argentina.  相似文献   

20.
Thelazia callipaeda is a spirurid nematode which causes ocular infections in dogs and man and, occasionally, in cats, foxes and rabbits. The intermediate host and vector of T. callipaeda is unknown. For a long time T. callipaeda incidence was reported only from the Russian Federation and the Far East, but recently it has also been found in Italy. In order to investigate the spread of T. callipaeda in Italy, a survey was carried out in two sites, site A in the Piedmont region (North West Italy), and site B in the Basilicata region (Southern Italy). Dogs, cats and foxes in site A and dogs in site B were examined for eyeworms, using different procedures and timing. From January 1995 to August 2002, 91 dogs, 4 cats and 903 fox carcasses were examined in site A, and from October 1999 to January 2003, 443 dogs were examined in site B, and the eyeworms collected were identified using morphological keys. Twenty-one (23.07%) and 185 (41.76%) of the dogs from sites A and B, respectively, were found to be infected by eyeworms; furthermore, all the cats examined and 46 fox carcasses (5.1%) were positive for eyeworms. All the nematodes collected were identified as T. callipaeda. These results indicate that T. callipaeda is not confined to Eastern Europe and Asia, but that it has spread to the Old Continent, and to both Northern and Southern Italy. Considering the high prevalence of infected dogs reported in some municipalities (e.g. 60.14% of 138 dogs examined in a municipality from site B), it is assumed that one or more vectors are significantly present in the areas under investigation. Furthermore, there is good reason to believe that T. callipaeda is also present in other European countries. Speculation as to the origins of this parasitic infestation in Europe and the biology of T. callipaeda and its vector/s is also discussed.  相似文献   

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