Canine angiostrongylosis: the French heartworm: an emerging threat in North America

Angiostrongylus vasorum, French heartworm, is a metastrongloid parasite found in the pulmonary arteries and right ventricle of wild and domestic canids and various other animals. The natural definitive hosts are species of foxes. The geographic distribution of the parasite includes various countries of Europe, Africa, South America, and North America. Angiostrongylosis is considered an emerging disease in dogs in Europe. In North America, autochthonous A. vasorum infection occurs only in the Canadian province of Newfoundland-Labrador. Computer modeling suggests there is a high probability that A. vasorum will spread to other parts of North America and will likely become endemic in the eastern half of the continent and in the states and provinces along the western coast. Animals acquire infection by the ingestion of gastropod or frog intermediate hosts that carry the infective 3rd-stage larvae. Frogs can also serve as paratenic hosts. Definitive antemortem diagnosis is by detection of L(1) in feces, sputum, or bronchoalveolar lavage samples. Baermann fecal examination is the most reliable method for fecal detection. However, false negative results can occur due to the typical erratic/sporadic fecal larval shedding pattern of A. vasorum. Recently, promising new methods for A. vasorum infection diagnosis have been reported involving polymerase chain reaction of blood and fecal samples and a sandwich ELISA for detection of circulating worm excretory/secretory antigen. Current treatment options include moxidectin, milbemycin oxime, and fenbendazole.     

Treatment of a Myasthenic Dog with Mycophenolate Mofetil

A ten‐year‐old, male castrated Springer Spaniel was presented for dysphagia, ptyalism, and regurgitation. Evidence of megaesophagus and mild aspiration pneumonia were apparent on thoracic radiographs. A diagnosis of focal acquired myasthenia gravis was suspected and subsequently confirmed with a positive serum acetylcholine (ACh) receptor antibody concentration (3.87 nM/L). A gastrostomy tube was placed shortly after presentation; food and drugs (including azathioprine) were administered through the tube. After transient improvement, the dog suddenly deteriorated clinically, experiencing frequent episodes of regurgitation and developing severe aspiration pneumonia. Mycophenolate mofetil (MMF), a novel immunosuppressive drug with relative specificity for lymphocytes, was instituted every twelve hours via the gastrostomy tube. Within four days of beginning MMF therapy, both clinical evidence of pharyngeal/esophageal dysfunction and radiographic evidence of megaesophagus had resolved. Initially, clinical side‐effects of combined MMF/AZA administration were not apparent, but the patient experienced several vomiting episodes during the third week of treatment. The vomiting resolved after decreasing the dose of both drugs. The patient made a full recovery, and a one‐month follow‐up ACh receptor antibody concentration was normal (0.26 nM/L). After one month of combination therapy, the patient was weaned off of AZA and maintained on MMF as the sole immunosuppressive drug. The dog was subsequently weaned off of MMF on two occasions. Mycophenolate mofetil was reinstituted after the first discontinuation due to the development of profound appendicular muscle weakness two days after stopping MMF; the weakness resolved within 24 hours of reinstituting MMF. A positive ACh receptor antibody concentration (0.89 nM/L) after the second MMF weaning prompted the second reinstitution of MMF. Two months following this second MMF reinstitution, the dog was again serologically negative (0.51 nM/L) for myasthenia gravis. At the time of last followup, the dog remained in clinical remission eight months after initial presentation. The use of MMF to treat acquired myasthenia gravis in dogs has not been reported previously. The literature concerning MMF and its potential use in treating patients with autoimmune diseases is discussed.     

我国部分地区牛支原体肺炎和关节炎的病原体诊断

重庆等4省市从外省引进的肉牛群发生以严重肺炎和关节炎为主要表现的疾病。该病的病变主要集中于肺脏,其组织学变化主要是间质增生,纤维素渗出,干酪样坏死,淋巴细胞、嗜中性粒细胞和单核细胞浸润。PCR检测病牛肺脏显示牛支原体阳性,而丝状支原体丝状亚种、牛分支杆菌和多杀性巴氏杆菌为阴性。从肺等组织中分离到牛支原体以及大肠杆菌、沙门氏菌、链球菌、葡萄球菌和烟曲霉,没有分离到巴氏杆菌。结果显示本病是以牛支原体感染为主引起的牛支原体肺炎和关节炎,长途运输等应激因素是该病突发的重要诱因,其他细菌和/或真菌继发感染加重了病情。     

二氟沙星对实验性感染猪支原体性肺炎及链球菌病的药效学研究

以试管两倍稀释法测得二氟沙星对猪肺炎支原体（ Ｆ１６ 株）和兰氏 Ｃ 群类马链球菌（ Ｃ５５ １ ２０ ）的最小抑菌浓度分别是０１６ｍ ｇ／ Ｌ及 １６ｍ ｇ／ Ｌ。肌注给药对猪支原体性肺炎及链球菌病的实验性治疗结果表明,低、中、高剂量二氟沙星组（２５、５、１０ｍ ｇ／ｋｇ）及蒽诺沙星组（２５ｍ ｇ／ｋｇ）用药 ５ 天（每隔 １２ 小时给药一次）对猪支原体性肺炎的治愈率分别是 ８０％ 、９０％ 、１００％ 及９０％ ;而支原体感染对照组的自愈率为１０％ 。低、中、高剂量二氟沙星组及蒽诺沙星组（２５ｍ ｇ／ｋｇ）用药 ４ 天（每隔 １２ 小时给药一次）对猪链球菌病的治愈率分别是 ５０％ 、８０％ 、８０％ 及 ８０％ ,而链球菌感染对照组的死亡率为 ５０％ 。     

Association between quantitative bacterial culture of bronchoalveolar lavage fluid and antibiotic requirement in dogs with lower respiratory tract signs

BackgroundHistorically, positive bacterial cultures from the lower respiratory tract (LRT) have been considered clinically relevant when quantitative bacterial cultures of bronchoalveolar lavage fluid (BALF) were >1700 colony forming units (cfu)/mL. However, this threshold might not accurately predict a requirement for antibiotics.ObjectivesTo study whether quantitative BALF bacterial culture results were predictive of antibiotic requirement in dogs with LRT signs.AnimalsThirty‐three client‐owned dogs.MethodsCross‐sectional study. Dogs with positive quantitative bacterial culture of BALF were included. Dogs were divided into 2 groups, depending on whether they had a LRT infection requiring antibiotics (LRTI‐RA) or LRT disease not requiring antibiotics (LRTD‐NRA), based on thoracic imaging features, presence of intracellular bacteria on BALF cytology, and response to treatment. Predictive effect of cfu/mL and BALF total nucleated cell count (TNCC) on antibiotic requirement, adjusting for ongoing or prior antibiotic therapy and age, were studied using logistic regression.ResultsTwenty‐two and 11 dogs were included in the LRTI‐RA and LRTD‐NRA groups, respectively. The cfu/mL was not significantly predictive of antibiotic requirement, independent of ongoing or prior antibiotic treatment and age (LRTI‐RA: median, 10 000 cfu/mL; range, 10‐3 × 10⁸; LRTD‐NRA: median, 10  000 cfu/mL; range, 250‐1.3 × 10⁹; P = .27). The TNCC was not significantly predictive of antibiotic requirement when only dogs with bronchial disease were considered (LRTI‐RA: median, 470 cells/μL; range, 240‐2260; LRTD‐NRA: median, 455 cells/μL; range, 80‐4990; P = .57).Conclusion and Clinical ImportanceThe cfu/mL is an inappropriate measure for determining whether antibiotics are of benefit in dogs with LRT signs.     

Susceptibility of cats to equine morbillivirus

Objective To assess the susceptibility of cats to equine morbillivirus (EMV) by direct administration of the virus by subcutaneous, intra-nasal or oral routes, and following exposure to infected cats.
Design A disease transmission study, with controls, using ten cats.
Procedure Groups of cats were given the virus by the designated methods and assessed for evidence of infection by clinical examination, plus pathological and virological tests.
Results All cats administered the virus by subcutaneous, intra-nasal or oral routes became infected and developed the disease within 4 to 8 days. One of two cats in contact with affected cats also developed the disease, but two cats kept near to affected cats did not become infected. The virus was isolated from a range of tissues collected from the infected cats, and the lesions observed in affected cats were similar to those previously observed in horses naturally and experimentally infected with the virus.
Conclusion This is the first demonstration that animals can be infected with EMV by non-parenteral means, that the virus can transmit naturally between animals and confirms other reports of the similarity of EMV disease in horses and cats.     

Pathogenicity for chickens of a paramyxovirus type 1, isolated from racing pigeons in Sweden

Strains of paramyxovirus type 1 (PMV-1) have been isolated from diseased racing pigeons in Sweden. One of these isolates was selected for studies of the pathogenicity and contagiousness in chickens.The same isolate was previously found to have a high intravenous pathogenicity index (IVPI) in 6 weeks old chickens.In three experiments it was found that the PMV-1 isolate was very pathogenic for 1 week old chickens but not pathogenic for 120 day old pullets inoculated intranasally and ocularly.Symptoms in the young chickens were similar to those seen in the neurotropic form of Newcastle disease. The mortality was high and the incubation period 5–11 days.The disease easily spread to young chickens kept in contact with diseased birds.The microscopic examination revealed an interstitial nonpurulent pneumonia and a nonpurulent encephalitis in the young chickens. In the pullets the only finding was a mild encephalitis.PMV-1 was recovered from all young chickens but not from the pullets.Both the chickens and the inoculated pullets developed antibodies to PMV-1.     

A case of idiopathic eosinophilic pneumonia in a Quarter Horse gelding

A 16-year-old Quarter Horse gelding was presented to the Kansas State Veterinary Health Center for acute onset of diffuse, nonpruritic, generalised and coalescing urticaria. A single dose of dexamethasone resulted in resolution of the urticaria within 24 h; however, 48 h after discharge, he presented with mild colic. The patient was febrile and thoracic ultrasound was abnormal, evidenced by bilateral pleural echogenic irregularities, mild pulmonary consolidation and slight unilateral pleural effusion. Thoracic radiographs also revealed caudoventral soft tissue opacity in the same region of the ultrasonographic abnormalities. Transtracheal wash was performed and broad spectrum antimicrobials initiated. Poor clinical response to therapy and marked peripheral eosinophilia resulted in the necessity for bronchoalveolar lavage, which revealed a predominance of pulmonary eosinophils. A diagnosis of acute idiopathic eosinophilic pneumonia was made. Treatment included a tapering dose of dexamethasone over 4 weeks. Due to incomplete disease resolution, the patient was moved to an alternate environment which resulted in disease resolution.