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1.
弓形虫是一种呈世界性分布的机会性致病原虫,可引起致命性脑炎.人弓形虫病急性感染往往与弓形虫卵囊污染密切相关.探究弓形虫卵囊感染对宿主的致病机制和防控弓形虫病具有重要意义.因此,本研究利用iTRAQ技术,结合2D-LC-MS/MS分析弓形虫PRU虫株卵囊急、慢性感染小鼠后,其脑组织蛋白质的差异表达情况.结果 表明,在急性...  相似文献   

2.
The infection of Yankassa rams with three important trypanosome species affecting livestock, namely, Trypanosoma congolense, T. vivax and T. bruceiproduced both acute and chronic fatal conditions. Chronic infections were induced in the three infections by the application of subcurative doses of diaminazene aceturate (Berenil). Pathological changes in the infected animals included splenomegaly and hepatomegaly which were more pronounced in acute than in chronic T. congolense infection. However, these changes were more severe in chronic than in acute T. vivax infection. While splenomegaly was more pronounced in chronic T. bruceiinfection than in acute, hepatomegaly and lymphadenopathy were more severe in acute than in the chronic condition. The increases in size of the spleen, lymph nodes and liver were associated with congestion, increases in cell density related to increased immunological reactions in the spleen and lymph nodes as well as increase in numbers, size and activity of the phagocytic cells in these organs.  相似文献   

3.
葡萄球菌感染是家禽养殖中一种常见的细菌性传染疾病,鸡养殖中的葡萄球菌感染通常是致病性金黄色葡萄球菌感染的一种慢性或急性传染性疾病,通常慢性疾病感染会导致鸡只出现关节炎症或者足部疾病,急性型感染会导致鸡只出现急性败血症病变。葡萄球菌感染疾病所导致的鸡只死亡率较高,尤其在雏鸡和育成阶段,对于成年鸡的死亡率相对较低,但是会对其生产性能和机体健康状况造成严重的损伤,进而影响鸡养殖的经济效益。该文主要对鸡养殖中葡萄球菌感染的临床症状,解剖检查变化及相关的防治措施进行论述。  相似文献   

4.
Intramammary infections by a nonspeciated Mycobacterium of Runyon group IV increased in the dairy herd at the Beltsville, Md, Agricultural Research Center during 4 years, and were cultured from 9.7% of 300 quarter samples from clinical mastitis cases in 1982. The infection was mildly acute, without systemic involvement, and refractory to therapy but self-terminating, usually at the end of lactation. Invasion of the mammary gland commonly followed stress, either calving or previous clinical mastitis, and was most frequent in August and September. Transmission of this mycobacterial intramammary infection from cow to cow was far more likely in free-stall barns than in tie stalls, and seemed not to be associated with machine milking.  相似文献   

5.
Staphylococcus aureus (S. aureus) often causes long-lasting chronic sub-clinical udder infections in dairy cows. To investigate if this can be due to a negative impact of S. aureus on lymphocytes important for the immune defence, alterations in proportions and expression intensity of CD4+, CD8+, WC1+, B and IL-2R+ lymphocytes was studied in blood and milk, as S. aureus mastitis developed from acute clinical to chronic sub-clinical form. Six healthy dairy cows were inoculated with S. aureus in one udder quarter per cow, and one quarter per cow acted as an uninfected control. Blood samples, and milk samples from infected and non-infected quarters were collected before infection and for five weeks after infection. All infected quarters developed acute clinical mastitis, of which five turned into chronic sub-clinical mastitis. In infected quarters, the proportions of all lymphocyte sub-sets, except WC1+ cells, differed in acute phase compared to pre-infection, while the dominant finding in the chronic phase was increased expression intensities per cell. An impact on blood lymphocytes and milk lymphocytes in non-infected quarters also occurred, mainly during the chronic phase. The most prominent finding was the increased proportion and expression of B-lymphocytes in blood, infected and non-infected quarters during chronic sub-clinical mastitis. As S. aureus can invade and survive intracellularly, a preferential stimulation of B-cells, suggesting development of a humoral response, may not be sufficient to eliminate intracellular bacteria, which could explain the persistence of the infection.  相似文献   

6.
Experimental transmission of Besnoitia caprae from naturally chronically-infected goats to susceptible ones was achieved by intra-nasal instillation and intra-conjunctival inoculation of cystozoite-containing suspensions, subcutaneous implantation of fascia containing cysts and alternate needle pricking between the infected and non-infected goats. Typical chronic symptoms developed in the fascia-infected does. Cystozoite inoculation into the eyes and mouth did not result in infection. Kids born of dams with acute and chronic besnoitiosis did not contract the infection in utero, suggesting that intra-uterine transmission may not occur. In contrast to does with acute besnoitiosis, which occasionally aborted, the does with chronic besnoitiosis gave birth to healthy kids. Kids below the age of 4 months (pre-weaned period) born of both infected and non-infected does were susceptible to besnoitiosis but appeared to be more resistant than adult goats.  相似文献   

7.
Both cytopathic and noncytopathic bovine viral diarrhea virus (BVDV) were isolated from 16 of 17 bovine spleens representing 11 herds that had experienced acute BVD and from 12 of 21 bovine spleens from 1 herd affected with chronic BVD. It was concluded that isolation of cytopathic and noncytopathic BVDV from the same spleen probably indicates that an animal with a persistent, noncytopathic BVDV infection was superinfected with a cytopathic BVDV. The prevalence (greater than 70%) of 2 viruses in the spleen of cattle with acute or chronic BVD suggested that persistent infection with noncytopathic BVDV may be an important factor in the pathogenesis of BVD.  相似文献   

8.
During the hunting season 1996-1999, blood samples were collected from wild boar shot in The Netherlands. Sera were screened for presence of antibodies against classical swine fever virus (CSFV), swine vesicular disease virus (SVDV), Aujeszky's disease virus (ADV), and Trichinella spiralis. The results indicate that CSFV, SVDV, and ADV are uncommon in the wild boar population. Therefore, it seems that CSFV, SVDV, and ADV infection in the wild boar population is not an important reservoir in The Netherlands. ADV and CSFV infections are endemic in the wild boar population in Germany. Since contact between the German and Dutch wild boar populations can not be excluded, continuation of the sero-surveillance system seems appropriate. In the decade before 1998, the wild boar population in The Netherlands seemed to be free of T. spiralis. Whether the finding, in the hunting season of 1998-1999, of a few wild boar with antibodies against T. spiralis is an artefact or not, should be investigated in further research.  相似文献   

9.
Brucella melitensis is an intracellular bacteria causing disease in humans as an incidental host. The infection initiates as acute flu-like symptoms and may transform into a chronic cyclic infection. This cyclic infection may be partly due to the bacteria’s ability to persist within antigen presenting cells and evade the CD8 + T cell response over long periods of time. This research aims to characterize the immune response of the acute and chronic forms of brucellosis in the murine liver and spleen. We also sought to determine if the exhaustion of the CD8 + T cells was a permanent or temporary change. This was accomplished by using adoptive transfer of acutely infected CD8 + T cells and chronically infected CD8 + T cells into a naïve host followed by re-infection. The histological examination presented supports the concept that exhausted T-cells can regain function through evidence of granulomatous inflammation after virulent challenge in a new host environment.  相似文献   

10.
Nephrosonography was compared to In-111 WBC for detection of experimentally induced pyelonephritis in 12 dogs. Nephrosonography was performed during the acute and chronic phase of pyelonephritis in all dogs. Sonographic abnormalities were found in all infected kidneys imaged early after infection. In the chronic phase of pyelonephritis, the sonographic abnormalities had decreased in severity in 9 kidneys, increased in severity in 2 kidneys, and had resolved in 2 kidneys. After histopathologic evaluation, eleven of fifteen kidneys (73%) with pyelonephritis had been identified by sonography. The In-111 WBC scan was performed during the acute phase of pyelonephritis in 9 dogs and during the chronic phase in all dogs. During the acute phase of pyelonephritis, the WBC scan was positive in 8 of the 9 dogs (89%) on images acquired 24 and 48 hr after injection of the labelled WBC. During the chronic phase of pyelonephritis, the WBC scan was negative in all 12 dogs. The sensitivity of the In-111 WBC scan was poor compared to nephrosonography for detection of chronic pyelonephritis. In this study, optimal detection of renal infection/pyelonephritis by In-111 WBC may be dependent on the presence of clinical signs and leukocytosis in dogs. Even when leukocytosis is present, the In-111 WBC may fail to accumulate in the kidney in dogs with pyelonephritis, particularly if no clinical signs (fever, depression, inappetence) are present.  相似文献   

11.
Feline heartworm disease is caused by the filarial nematode Dirofilaria immitis, and is transmitted by mosquitoes in heartworm-endemic areas worldwide. While dogs are the definitive hosts for this parasite, cats can also be infected, and the overall prevalence in cats is between 5% and 10% of that in dogs in any given area. The spectrum of feline presentations varies from asymptomatic infections to chronic respiratory signs, sometimes accompanied by chronic vomiting to acute death with no premonitory signs. Ante-mortem diagnosis can be challenging and relies on a combination of tests, including antigen and antibody serology, thoracic radiography and echocardiography. As treatment with heartworm adulticidal drugs can be life-threatening and heartworm infection in cats is often self-limiting, infected cats are frequently managed with supportive treatment (corticosteroids, bronchodilators, and anti-emetics). Surgical removal of filariae using extraction devices may be considered in some acute cases where immediate curative treatment is necessary, but filarial breakage during the procedure may result in an acute fatal shock-like reaction. Necropsy findings are mainly pulmonary and include muscular hypertrophy of the pulmonary arteries and arterioles on histopathology. A number of safe and effective macrocytic lactone drugs are available for prophylaxis in cats. These drugs can kill a range of larval and adult life-cycle stage heartworms, which may be advantageous in cases of owner compliance failure or when heartworm infection status is undetermined at the time prophylaxis is commenced. An index of suspicion for feline heartworm disease is warranted in unprotected cats with respiratory signs, and perhaps chronic vomiting, in areas where canine heartworm disease is endemic. Many cats, once diagnosed and with appropriate supportive care and monitoring, will resolve their infection and be free of clinical signs.  相似文献   

12.
Toxoplasma gondii infection was established in sheep seven days (acute infection) or 28 days (chronic infection) before they were given enzootic abortion (EAE) vaccine alone or simultaneously with louping-ill (LI) vaccine. Uninfected controls received the same vaccination schedule. The serological response of acute toxoplasma-infected sheep to initial LI vaccination was significantly depressed but after revaccination four weeks later these sheep demonstrated a response equal to that of the revaccinated controls. Infected sheep also gave a significantly poorer response to EAE vaccine than control animals, the effect being more marked in those with chronic infection. Revaccination evoked no clear response in any group but on three of five sampling days antibody titres of controls were significantly higher than those of infected sheep.  相似文献   

13.
The course of experimental Trypanosoma vivax infection in eight Uda rams was studied. All the infected animals became parasitaemic 2 days post-inoculation and remained so throughout the study period. A three-phase disease pattern was recognized, i.e. acute, subacute and chronic stages lasting 17-85 days. The disease was characterized by fever and a terminal decrease in rectal temperature despite an increase in parasitaemia with time for rams with acute and subacute infections. Mean weight loss was most marked in subacute followed by chronic cases. Gross pathological changes observed in some infected rams with subacute and chronic trypanosomosis were oedema of the face and lower jaw, hydropericardium and atrophy of the pericardial fat. Petechial haemorrhages were observed on the surfaces of the heart and kidney of rams with acute infection. Anaemia was most severe in infected rams with acute disease, followed by those with subacute infections. Also, hypoproteinaemia was observed in all infected rams. Severe clinical findings associated with the death of all the infected rams during this study might indicate that the Uda breed of sheep in very susceptible to trypanosomosis. It is, therefore, recommended that this breed of sheep, which is strictly bred and reared in tsetse-free Sahel savannah, should not be introduced into endemic areas devoid of therapeutic cover and strict tsetse fly control.  相似文献   

14.
Q fever is an endemic disease in different parts of Greece. The current study aimed to investigate the prevalence of acute Q fever disease in Greece through the operation of the national reference centre for Q fever.A total of 5397 sera were received from febrile patients under the suspicion of Q fever infection during a 13 years period (2001–20013). A questionnaire was filled in by the clinicians containing certain clinical/epidemiological/demographic information.The diagnosis was based both on IFA (IgG and IgM phase II antibodies against Coxiella burnetii) and on molecular means.A total of 685 (12.7 %) samples were initially tested positive for acute Q fever. The mean (±SD) age of patients was 55.3 years (±18.7). Out of the 489 convalescent samples, 134 (27.4 %) samples indicated a minimum of a four-fold seroconversion and were considered as laboratory confirmed cases of acute Q fever. Pneumonia was the most frequently encountered clinical symptom with presence in 6.8 % of all positive samples. Forty six (46) patients were laboratory confirmed as chronic Q fever cases.Climate seemed to influence the distribution of Q fever cases throughout the years. The findings of the current study comply with past studies carried out elsewhere that had demonstrated a clear relation of the disease with temperature, south winds, etc.This study represents the first large scale attempt to gather a long period information on Q fever infection in Greece. The findings of the current study support the fact that Q fever is an important endemic zoonotic disease in Greece and needs increased awareness by clinical physicians and health care system.  相似文献   

15.
In recent decades, sporadic cases of ocular Onchocerca species infection have been reported in dogs in the USA and Europe. In the acute stage of the disease severe inflammation of the ocular and periocular tissues was observed. In chronic cases, the strongly coiled, gravid nematodes were incorporated in pea- to bean-sized granulomatous nodules in various parts of the eye, including the retrobulbar space, orbital fascia, eyelid, third palpebra, conjunctiva and sclera. Apart from the ophthalmological significance of the disease, the large number of microfilariae in the skin may be responsible for acute and chronic dermatological problems. The geographical distribution and prevalence of the infection may be greater than currently thought, because the lesions may have been erroneously regarded as other ocular diseases. Onchocerciasis is the world's second most prevalent infectious cause of blindness in human beings and parasitologists have long searched for an experimental model of human onchocerciasis; ocular onchocercosis infections in dogs may provide a useful experimental system.  相似文献   

16.
Demyelination is the prominent histopathological hallmark in the acute stage of canine distemper virus infection. Magnetic resonance imaging is an important diagnostic tool in human beings to determine demyelination in the brain, for example in multiple sclerosis. Five young dogs with clinically suspected canine distemper virus infection were subjected to magnetic resonance imaging of the brain and histopathological and immunohistochemical examinations. Hyperintense lesions and loss of contrast between grey and white matter were detected in T2-weighted images in the cerebellum and/or in the brainstem of three dogs, which correlated with demyelination demonstrated in histopathological examination. Furthermore, increased signal intensities in T2-weighted images were seen in the temporal lobe of four dogs with no evidence of demyelination. Magnetic resonance imaging seems to be a sensitive tool for the visualisation of in vivo myelination defects in dogs with acute canine distemper virus infection. Postictal oedema and accumulation of antigen positive cells have to be considered an important differential diagnosis.  相似文献   

17.
Influence of the injection site on bioavailability in dogs was investigated for injections with ampicillin anhydrate or amoxycillin trihydrate suspensions. Firstly, pharmacokinetic parameters were calculated after IV administration of the sodium salts. Then the dogs were injected in the neck (SC), in the lateral thorax region (SC), in the back (IM) and in the thigh (IM), respectively. The most obvious depot effect was seen after subcutaneous injection of ampicillin in the thorax region, though bioavailability seemed to be low. No differences were seen between the injection sites with amoxycillin. For ampicillin SC injection in the neck seems most favourable; for amoxycillin SC injection may be preferred because it is less burdening. Serum concentrations with amoxycillin were higher and persisted longer than with ampicillin. Further investigation is necessary to determine whether this also counts for tissues or focus of infection.  相似文献   

18.
许天赐  何洪荣 《野生动物》2011,32(3):158-159
江苏常州武进淹城野生动物世界从2007年10月至2011年3a多的时间所饲养的袋鼠中,共发生6例齿槽感染,4例呈急性经过,2例呈慢性经过。1例急性感染病例感染部位发生在上颌右侧分支后缘,其余5例均发生在下颌分支后缘。齿槽感染是动物园养殖袋鼠的一种常见病。上下颌均可感染,其中下颌齿槽感染的病例较上颌齿槽感染的多;急性感染病例若能及时发现,及时治疗,其预后一般较好;慢性经过病例预后通常不好。发病袋鼠不分性别,发病率和复发率都较高。  相似文献   

19.
Rabbit hemorrhagic disease virus (RHDV) is the etiologic agent of rabbit hemorrhagic disease (RHD), an acute lethal infection that kills 90% of adult rabbits due to severe acute liver inflammation. Interestingly, young rabbits are naturally resistant to RHDV infection. Here, we have compared naturally occurring CD4(+)Foxp3(+) regulatory T cells (Tregs) between young and adult rabbits after infection by RHDV. The number and frequency of Tregs was decreased in the spleen of adult rabbits 24h after the RHDV infection; this was in contrast with the unchanged number and frequency of splenic Tregs found in young rabbits after the same infection. Also, serum levels of IL-10 and TGF-β were enhanced in the infected adult rabbits whereas no alteration was observed in infected young rabbits. However, this increase is accompanied by a burst of pro-inflammatory cytokines, but seems not able to prevent the death of the animals with severe acute liver inflammation in few days after infection. Since Tregs downregulate inflammation, we conclude that their decrease may contribute to the natural susceptibility of adult rabbits to RHDV infection.  相似文献   

20.
Trypanosoma brucei infection produced an acute and fatal disease in Nigerian mongrel dogs due to a rapidly developing anaemia. Infected dogs responded with increased reticulocytosis, which was not sustained with chronicity. In comparison the response to artificially-induced haemolytic anaemia was progressive, marked and sustained. The anaemia of T. brucei infection of dogs was either normocytic normochromic in acute infection or microcytic normochromic in chronic infection. Artificially-induced haemolytic anaemia was either macrocytic normochromic or normocytic normochromic. The erythropoietic potential of plasma in vivo in mice increased in T. brucei-infected dogs except at the terminal parasitaemia. The anaemia in Trypanosoma brucei-infected dogs is therefore initially responsive but becomes poorly involved with chronicity.  相似文献   

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