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1.
During early lactation, dairy cows may present a transient immunosuppressive state and develop anaplasmosis caused by Anaplasma marginale. In this study, clinical anaplasmosis in dairy cattle in the Thrace region of Turkey was investigated with respect to within-herd prevalence, vertical transmission, and genetic diversity. In March and September 2015, thirty lactating cows showed primary clinical signs of anaplasmosis, including fever, anaemia, decreased milk yield, anorexia, and laboured breathing. Symptoms disappeared in most cows after administration of long-acting oxytetracycline, but nine of them (30%) died. Following diagnosis based on clinical signs, microscopy and molecular findings, blood samples were collected from apparently healthy lactating cows (n = 184), pregnant heifers (n = 39) and newborn calves (n = 24). DNA was extracted from each sample and analyzed for the presence of major surface proteins (MSPs) of A. marginale, followed by sequencing to assess diversity of isolates. Microscopic examination of erythrocytes revealed A. marginale inclusion bodies in symptomatic cows. Examination of thin blood smears showed 3.8% of the lactating, clinically asymptomatic, cows to be infected with A. marginale, while nPCR detected 31.0% positive. A. marginale infection was not detected in pregnant heifers by either method. Congenital infection was found in one calf by nPCR. This is the first report of transplacental transmission of A. marginale in Turkey. The MSP4 sequence analyses showed high genetic diversity among the isolates, presenting 97.6-99.6% homology at the amino acid level. The sequences of MSP1a amplicons revealed genetic diversity providing three new tandem repeats. 相似文献
2.
Hungerford, L.L. and Smith, R.D., 1997. Variations in seroprevalence and host factors for bovine anaplasmosis in Illinois. Veterinary Research Communications, 21 (1), 9-18.The modified card agglutination test (MCAT) was used to detect antibodies to Anaplasma marginale in 4994 samples collected from market cattle through the Brucellosis Eradication Program in Illinois. The MCAT reactor rate in the sample was 6.4%. The statewide prevalence estimate increased to between 7.1% and 10.7% when corrected for sampling distribution and test sensitivity and specificity. While the sample reactor rate measures the proportion of infected cattle moving through the market system and into new herds, consideration of the sampling proportions and test characteristics is important when estimating the overall prevalence. Cows were found to be at decreased risk relative to male cattle in lower-prevalence areas, but the risk was similar in higher-prevalence areas. In both higher- and lower-prevalence areas, the risk for seropositivity increased from 1 year of age onwards, but the rate of increase with age was greater in the higher-prevalence areas. Calves, however, had higher seroprevalence levels than 1-2-year-old animals. The risk was highest for Angus and Angus-Hereford cross cattle, while dairy cattle showed a decreased risk in the whole sample, but not when the analyses were stratified by prevalence level. There was a higher concentration of dairy cattle in areas with lower prevalence levels. 相似文献
3.
P. Franzén A. Aspan A. Egenvall A. Gunnarsson E. Karlstam J. Pringle 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(3):636-642
Background: Anaplasma phagocytophilum infects several mammalian species, and can persist in sheep, dogs, and calves. However, whether this organism persists in horses or induces long-term clinical abnormalities is not known.
Objectives: To evaluate whether A. phagocytophilum can persist in horses and to document clinical findings for 3 months after complete recovery from acute disease.
Animals: Five clinically normal adult horses that had recovered spontaneously from experimentally induced acute disease caused by a Swedish equine isolate of A. phagocytophilum .
Methods: Horses were monitored for up to 129 days post inoculation (PI) by daily clinical examination and at least alternate day blood sampling for evidence of A. phagocytophilum on polymerase chain reaction (PCR) and blood smears. All horses were euthanized and underwent postmortem examination.
Results: All horses were periodically PCR positive after recovery from acute infection. Before day 66 PI 2 horses were persistently PCR negative whereas 3 horses were intermittently PCR positive. Subsequently, 4 of 5 horses were intermittently PCR positive, particularly after stress mimicking interventions. One animal was positive immediately before postmortem examination. Clinical abnormalities related to persistence of anaplasma were not observed. No specific changes were found at postmortem examination, and all sampled tissues from all horses were negative on PCR for A. phagocytophilum .
Conclusions and Clinical Importance: Infection with A. phagocytophilum can persist in the horse for at least 129 days. However, the continued presence of the organism is not associated with detectable clinical or pathological abnormalities. 相似文献
Objectives: To evaluate whether A. phagocytophilum can persist in horses and to document clinical findings for 3 months after complete recovery from acute disease.
Animals: Five clinically normal adult horses that had recovered spontaneously from experimentally induced acute disease caused by a Swedish equine isolate of A. phagocytophilum .
Methods: Horses were monitored for up to 129 days post inoculation (PI) by daily clinical examination and at least alternate day blood sampling for evidence of A. phagocytophilum on polymerase chain reaction (PCR) and blood smears. All horses were euthanized and underwent postmortem examination.
Results: All horses were periodically PCR positive after recovery from acute infection. Before day 66 PI 2 horses were persistently PCR negative whereas 3 horses were intermittently PCR positive. Subsequently, 4 of 5 horses were intermittently PCR positive, particularly after stress mimicking interventions. One animal was positive immediately before postmortem examination. Clinical abnormalities related to persistence of anaplasma were not observed. No specific changes were found at postmortem examination, and all sampled tissues from all horses were negative on PCR for A. phagocytophilum .
Conclusions and Clinical Importance: Infection with A. phagocytophilum can persist in the horse for at least 129 days. However, the continued presence of the organism is not associated with detectable clinical or pathological abnormalities. 相似文献
4.
湖南省牛无浆体虫株分子生物学鉴定 总被引:1,自引:0,他引:1
用原虫16 S rRNA基因序列通用引物对湖南5个地区牛无浆体感染的阳性血液样品进行PCR扩增,经测序和序列拼接,获得5个无浆体样品16 S rRNA基因的部分序列,应用分子生物学软件进行分析,并根据所获得序列的保守区间设计特异性引物,进行PCR诊断方法的探讨性研究.结果表明,在通用引物下,5个地区无浆体感染的阳性血液样品均获得1 425 bp大小的虫体16 S rRNA基因条带;测序后5个无浆体16 S rRNA序列同源性均在97%~98%.证明5个分离虫株初步鉴定为牛边缘无浆体. 相似文献
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6.
K.H. Jäderlund K. Bergström A. Egenvall Å. Hedhammar 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(3):669-672
Background: The tick-borne bacteria Borrelia burgdorferi sensu lato (sl) and Anaplasma phagocytophilum have been suspected to cause neurological signs in dogs. Diagnosis often has been made based on positive antibody titers in serum of dogs with neurological signs, but a high seroprevalence in dogs in at-risk populations makes diagnosis difficult.
Objective: To determine if the neurological signs in dogs examined were caused by any of these bacteria.
Animals: Fifty-four dogs presented to a board-certified neurologist.
Methods: Prospective study. We divided dogs into 2 groups: those with inflammatory diseases of the central nervous system (CNS) and those with neurological signs from other diseases. Blood and cerebrospinal fluid (CSF) from all dogs were analyzed.
Results: Dogs with inflammatory CNS diseases showed no serum antibodies against any of the agents. Among dogs with neurological signs from other diseases, 10.3% had serum antibodies for B. burgdorferi sl and 20.5% for A. phagocytophilum . All blood samples analyzed for bacterial deoxyribonucleic acid (DNA) and all CSF analyzed for antibodies and bacterial DNA for the 2 agents were negative.
Conclusions and Clinical Importance: Based on this study, these bacteria are unlikely causes of neurologic disease in dogs and the presence of serum antibodies alone does not document or establish a definitive diagnosis of CNS disease caused by these organisms. Dogs that have neurologic disease and corresponding serum antibodies against these agents should have additional tests performed to assess for other potential etiologies of the signs. 相似文献
Objective: To determine if the neurological signs in dogs examined were caused by any of these bacteria.
Animals: Fifty-four dogs presented to a board-certified neurologist.
Methods: Prospective study. We divided dogs into 2 groups: those with inflammatory diseases of the central nervous system (CNS) and those with neurological signs from other diseases. Blood and cerebrospinal fluid (CSF) from all dogs were analyzed.
Results: Dogs with inflammatory CNS diseases showed no serum antibodies against any of the agents. Among dogs with neurological signs from other diseases, 10.3% had serum antibodies for B. burgdorferi sl and 20.5% for A. phagocytophilum . All blood samples analyzed for bacterial deoxyribonucleic acid (DNA) and all CSF analyzed for antibodies and bacterial DNA for the 2 agents were negative.
Conclusions and Clinical Importance: Based on this study, these bacteria are unlikely causes of neurologic disease in dogs and the presence of serum antibodies alone does not document or establish a definitive diagnosis of CNS disease caused by these organisms. Dogs that have neurologic disease and corresponding serum antibodies against these agents should have additional tests performed to assess for other potential etiologies of the signs. 相似文献
7.
E. L. Deane C. L. Fielding D. M. Rhodes E. J. Howard 《Equine Veterinary Education》2021,33(3):e58-e61
An adult Quarter Horse gelding (Case 1) was evaluated for tachypnoea and acute dysphagia. A 20-year-old Quarter Horse gelding (Case 2) was evaluated for respiratory stertor and severe, acute swelling of the head in the submandibular region. A physical examination, complete blood count, blood chemistry, upper airway endoscopy, and peripheral blood Anaplasma phagocytophilum polymerase chain reaction were completed for both horses. Both horses tested positive for A. phagocytophilum. The upper airway endoscopy for Case 1 revealed a feed contaminated pharynx, absent swallowing reflex, and left laryngeal hemiplagia. The upper airway endoscopy for Case 2 revealed severe diffuse pharyngeal swelling occluding the airway. Due to increased respiratory effort in Case 2, a tracheotomy was performed. In both horses, treatment consisted of intravenous oxytetracycline 6.6 mg/kg bwt i.v. q. 24 h for 2–3 days followed by minocycline 4 mg/kg bwt per os q. 12 h for 10–14 days. Both horses made full recoveries. 相似文献
8.
Losses from morbidity and mortality due to anaplasmosis were assessed in beef and dairy cattle of the Red River Plains and south-east areas of Louisiana. The cost of treatment and prevention of anaplasmosis and losses in milk production and those due to deaths or culling were valued at $0.5 million for the year 1983 in these two areas. The cost of prevention included the use of tetracyclines in feed and salt-mineral supplements, injectable tetracycline, vaccination and an estimated 10% of the cost of insecticidal ear tags, sprays, pour-on applications and dust bags. The remainder of these costs and the total cost of vector control in dairy cattle was attributed to the control of fly annoyance. Treatment costs included veterinary fees and the owner's treatment costs, including labour costs. 相似文献
9.
应用国产咪唑苯脲,按2mg/kg剂量肌肉注射治疗20例驽巴贝西虫病马,14例间隔24h用药2次,6例仅用药1次,均获治愈。按1~4.5mg/kg剂量一次肌肉注射治疗45例双芽巴贝西虫病黄牛,29例早、中期病例全部治愈,16例晚期病例,治愈14例,治愈率87.5%。按1.5mg/kg剂量一次肌肉注射治疗4例双芽巴贝西虫病黄牛,全部治愈。以1mg/kg,1.5mg/kg、2mg/kg剂量一次肌肉注射治疗46例水牛巴贝西虫病牛,1mg/kg剂量治疗12例,治愈9例,治愈率75%;1.5mg/kg剂量组24例及2mg/kg剂量组10例全部治愈。应用1.5mg/kg剂量间隔24h 2次肌肉注射治疗18例羊泰勒虫病羊,治愈16例,治愈率88.9%。以1~4.5mg/kg剂量1~8次肌肉注射治疗22例无定形体病牛,17例早、中期病例全部治愈,5例晚期病例全部死亡,治愈率77.3%。咪唑苯脲安全性较好,对牛、马加大剂量至8mg/kg,水牛6mg/kg,仅出现一过性的呼吸困难、流涎、肌肉颤抖、腹痛和排稀粪等副反应,约经30min后消失。 相似文献
10.
The indirect fluorescent antibody test was used to detect antibodies to Anaplasma marginale in serum samples collected from cattle in the Red River Plains and South-east areas of Louisiana. Convenience sampling of herd clusters was used. A reactor rate of 7.8% was found in 11 085 samples. Beef cattle had a 11.2% reactor rate compared with 3.8% for dairy cattle. The Angus and Angus cross-breed group had the highest reactor rate. 相似文献