Comparison of the lesions of Aleutian disease in mink and hypergammaglobulinemia in ferrets.

Gross and microscopic lesions of Aleutian disease (AD) in mink and hypergammaglobulinemia in ferrets were compared. Both conditions were characterized by widespread proliferation of plasma cells, but proliferation was more prominent in mink infected with AD. Arteritis did not occur in hypergammaglobulinemic ferrets. Minimal or no glomerular alterations occurred in infected ferrets, but were severe in mink infected with AD. Bile duct proliferation was more prominent in diseased mink. Tissue alterations suggested that AD in Aleutian genotype mink is more rapidly progressive than is AD in ferrets, causing overt clinical disease and death. In contrast, hypergammaglobulinemia in ferrets appeared to progress more slowly, with little clinical evidence of disease. This is probably the result of a paucity of glomerular lesions in ferrets. Possible mechanisms to explain the differences in the development of lesions are discussed.     

Aleutian disease in the ferret

Ferrets inoculated with Aleutian disease (AD)-infective material of mink origin harbored the infective agent for at least 136 days after inoculation. In contrast, hamsters given a similar inoculum of infective material no longer harbored the infective agent at 21 days postinoculation. During the infective period, neither ferrets nor hamsters had any detectable illness. However, in certain ferrets, massive periportal lymphocytic infiltrates were observed. A survey of ferrets from different ranches revealed similar lymphocytic infiltrates only in ferrets raised on a ranch which had AD-infected mink.     

Aleutian disease in two domestic striped skunks (Mephitis mephitis)

This report describes the use of polymerase chain reaction and DNA in situ hybridization to diagnose Aleutian mink disease parvovirus DNA in various tissue specimens from 2 companion striped skunks. Clinical, laboratory, and microscopic findings also support a clinical diagnosis of Aleutian disease in these mink.     

Characteristics of inapparent Aleutian disease virus infection in mink.

Inapparent of nonprogressive Aleutian disease virus (ADV) infection is a subclinical but persistent virus infection of mink. Mink with the inapparent type of ADV infection when subjected to stress did not develop the progessive form of the disease. However, when challenged with a large dose of the virus, these mink did develop progressive Aleutian disease indicating that they were not highly resistant to the virus. Sera of mink with either the progressive of the inapparent type of ADV infection did not neutralise the virus. The anti-ADV antibody activity in mink with inapparent type of ADV infection was in the IgG fraction of the serum the same as in mink with progressive Aleutian disease. These data indicate that the resistance of the mink with inapparent infection as compared to mink with progressive Aleutian disease was not due to a difference in the class of immunoglobulin response to the virus. However, mink with progressive Aleutian disease showed a greatly increased immunoglobulin response.     

Outbreak of canine distemper in domestic ferrets (Mustela putorius furo)

In 2006 an outbreak of canine distemper affected 14 young domestic ferrets in Barcelona, Spain. Their clinical signs included a reduced appetite, lethargy, dyspnoea, coughing, sneezing, mucopurulent ocular and nasal discharges, facial and perineal dermatitis, diarrhoea, splenomegaly and fever. Late in the course of the disease, general desquamation and pruritus, and hyperkeratotic/crusting dermatitis of the lips, eyes, nose, footpads, and perineal area were observed. None of the ferrets developed neurological signs. Non-regenerative anaemia and high serum concentrations of alpha- and beta-globulins were the most common laboratory findings. Most of the animals died or were euthanased because of respiratory complications. Postmortem there were no signs of lung collapse. Distemper was diagnosed by direct immunofluorescence of conjunctival swabs or pcr of several organs, and histology revealed the characteristic eosinophilic intracytoplasmic and intranuclear inclusion bodies of canine distemper virus in several organs. The minimum incubation periods calculated for six of the ferrets were 11 to 56 days, and in 13 of the ferrets the signs of disease lasted 14 to 34 days. Inclusion bodies compatible with infection by herpesvirus were found in the lungs of one of the ferrets.     

水貂阿留申病毒的分子生物学研究进展

从水貂阿留申病毒(ADV)基因组特点出发,就阿留申病毒的分子生物学研究进展作以简单综述。     

Nucleotide sequence and polymerase chain reaction/restriction fragment length polymorphism analyses of Aleutian disease virus in ferrets in Japan.

Two ferrets with spontaneous Aleutian disease (AD) were found in Japan. The diagnosis was verified by polymerase chain reaction (PCR) amplification of part of the capsid gene specific to AD virus (ADV). The nucleotide sequences (365 bp in length) of the amplified fragments from the 2 ferrets differed by a single nucleotide, producing an amino acid alteration. Compared with other types of ADV, these isolates had 96% sequence similarity to a published ferret ADV (FADV) in contrast to <91% homology to various types of mink ADV (MADV). The phylogenetic tree of ADVs indicates that these 2 isolates and the published FADV belong to the same genetic group and definitely are divergent from MADVs. The predicted amino acid sequence of the hypervariable segment in the capsid gene was conserved among the 3 types of FADV. These results indicated that the 2 isolates found in Japan were new DNA types of FADV and could have been derived from FADV(s). A restriction fragment length polymorphism (RFLP) method to distinguish the ferret types of ADV from the mink types of ADV was developed on the basis of differences in their nucleotide sequences. Digestion of the PCR products with Afal or ScaI provided different cleavage patterns for FADV and MADV. This PCR/RFLP analysis of the ADV capsid gene will be a valuable asset for diagnosis of this virus infection in ferrets.     

水貂阿留申病诊断抗原研究概述

近年来,随着水貂养殖行业的不断发展,一些疫病也成为了制约水貂养殖业发展的重要因素。水貂阿留申病作为毛皮动物的三大疫病之一(阿留申病、犬瘟热、病毒性肠炎),是导致母貂产仔率下降、公貂配种能力降低和毛皮质量下降的一种高度接触性传染病。至今为止,还没有商品化的疫苗来控制该病的传播及蔓延。控制水貂阿留申病最好的方法是通过检测淘汰所有抗体为阳性的水貂,进而达到净化貂群的目的。而在抗体检测过程中,诊断抗原的制备和纯化决定着检测方法的敏感性、特异性和准确性。论文对目前阿留申病毒细胞抗原及基因工程抗原研究进展做一综述,为今后该病病原检测工作提供参考。     

Transmission of Mycobacterium bovis from experimentally infected ferrets to non-infected ferrets (Mustela furo)

AIMS: To demonstrate the transmission of Mycobacterium bovis infection from experimentally infected ferrets (Mustela furo) to non-infected ferrets in a laboratory setting, using three different isotypes of M. bovis, and to observe ferret behaviour that might be implicated in disease transmission. METHODS: Three female ferrets, each experimentally infected with a unique strain of M. bovis, were housed together with six female and two male non-infected ferrets in an isolation facility. Transmission of infection was monitored clinically, serologically (using an ELISA test), bacteriologically, histologically, and by isotype analysis of M. bovis isolates using spoligotyping to determine whether or not transmission of each strain occurred. Ferret behaviour was observed using a time-lapse video recorder. RESULTS: Transmission of M. bovis infection was confirmed in two male and four female ferrets. Isotype analysis showed that of the experimentally infected females, one did not infect any other ferret, another transmitted M. bovis to one ferret before it died prematurely 49 days post-infection, and the third, which was cannibalised, appears to have transmitted M. bovis to both males and three females. However, two of these latter three females had died before the event of cannibalism took place. One female was infected with two strains. Several behavioural interactions were observed that could have resulted in M. bovis transmission, including den sharing, sniffing of orifices and faeces, cannibalism and aggressive breeding behaviour. CONCLUSIONS: Horizontal transmission of M. bovis infection was demonstrated in ferrets under experimental housing conditions. Routes of transmission may involve cannibalism and factors such as den sharing, playing, fighting, mating, and sniffing of faeces.     

Pneumonia due to Mycobacterium abscessus in two domestic ferrets (Mustelo putorius furo)

Two ferrets were diagnosed with pneumonia due to Mycobacterium abscessus. Both cases were treated successfully using clarithromycin after positive cultures were obtained via unguided bronchoalveolar lavage. This is the first time M abscessus has been isolated in our laboratory and the first report of this organism causing disease in companion animals in Australia. Underlying respiratory tract disease was thought to be an important factor in the development of the infections. Thorough investigation of chronic lower respiratory tract disease in ferrets is recommended as this species appears predisposed to atypical infections.     

Cryptococcosis in ferrets: a diverse spectrum of clinical disease

Cryptococcosis was diagnosed in seven ferrets (five from Australia; two from western Canada) displaying a wide range of clinical signs. Two of the ferrets lived together. One (5-years-old) had cryptococcal rhinitis and presented when the infection spread to the nasal bridge. Its sibling developed cryptococcal abscessation of the right retropharyngeal lymph node 12 months later, soon after developing a severe skin condition. DNA fingerprinting and microsatellite analysis demonstrated that the two strains isolated from these siblings were indistinguishable. Two ferrets (2- to 3-years-old) developed generalised cryptococcosis: one had primary lower respiratory tract disease with pneumonia, pleurisy and mediastinal lymph node involvement, while in the other a segment of intestine was the primary focus of infection with subsequent spread to mesenteric lymph nodes, liver and lung. The remaining three ferrets (1.75 to 4-years-old) had localised disease of a distal limb, in one case with spread to the regional lymph node. Cryptococcus bacillisporus (formerly C. neoformans var gattii) accounted for three of the four infections in Australian ferrets where the biotype could be determined. The Australian ferret with intestinal involvement and the two ferrets from Vancouver had C. neoformans var grubii infections.     

Transmission of Aleutian disease from mink with inapparent infections.

In apparent or nonprogressive Aleutian disease virus infection was considered a subclinical but persistent viral infection in which infected mink did not develop tissue lesions, hypergammaglobulinemia, or high antibody titers. Transmission of Aleutian disease virus from mink with this type of infection was measured. Mink with inapparent Aleutian disease appeared healthy and had normal gamma-globulin values, but were capable of transmitting the disease by direct and indirect horizontal contact. The risk of direct or indirect horizontal transmission from mink with inapparent infection was less than from mink with progressive Aleutian disease. Infection also was directly transmitted from the dam to the kits, but again the risk of infection from dams with inapparent infection was less than from dams with progressive Aleutian disease. Mink infected from their dams before weaning developed the disease more slowly than mink which became infected after weaning.     

Hepatobiliary inflammation,neoplasia, and argyrophilic bacteria in a ferret colony

Hepatobiliary disease was diagnosed in eight of 34 genetically unrelated cohabitating pet ferrets (Mustela putorios furo) during a 7-year period. The eight ferrets ranged in age from 5 to 8 years and exhibited chronic cholangiohepatitis coupled with cellular proliferation ranging from hyperplasia to frank neoplasia. Spiral-shaped argyrophilic bacteria were demonstrated in livers of three ferrets, including two with carcinoma. Sequence analysis of a 400-base pair polymerase chain reaction product amplified from DNA derived from fecal bacteria from one ferret demonstrated 98% and 97% similarity to Helicobacter cholecystus and Helicobacter sp. strain 266-1 , respectively. The clustering of severe hepatic disease in these cohabitating ferroes suggests a possible infectious etiology. The role of Helicobacter species and other bacteria in hepatitis and/or neoplasia in ferrets requires further study.     

Detection of antibody in Aleutian disease of mink: comparison of enzyme-linked immunosorbent assay and counterimmunoelectrophoresis

Experiments were undertaken to investigate the potential of the enzyme-linked immunosorbent assay (ELISA) as a screening test for the diagnosis of the 2 known naturally occurring forms of Aleutian disease of mink. Anti-Aleutian disease virus (ADV) antibody activity was not detectable in the sera of mink with nonprogressive Aleutian disease despite the demonstration of antibody by counterimmunoelectrophoresis (CIEP) in the same sera. Anti-ADV antibody was detectable in 93% of sera from mink at various stages of experimentally induced progressive Aleutian disease. False-negative reactions occurred in sera which demonstrated high anti-ADV antibody titers by CIEP. As a consequence of the high prevalence of false-negative reactions, the ELISA was not considered to be an effective screening test. However, using CIEP as an indicator of ADV infection, the ELISA may be useful in differentiating mink with nonprogressive Aleutian disease from mink with progressive Aleutian disease.     

Circumcaval ureter in two ferrets

BackgroundCircumcaval ureter is an anomaly in the development of the caudal vena cava, rarely reported in ferrets.Materials and methodsInclusion criteria for ferrets were circumcaval ureter confirmed on surgery or post-mortem examination. Data collection of ferrets with circumcaval ureters presented between January 2014 and January 2021 included signalment, medical history, clinical signs, laboratory diagnostics, diagnostic imaging results, treatments, and clinical outcomes.ResultsTwo ferrets met the inclusion criteria. One presented following diarrhea, and one was found on routine examination that revealed a right nephromegaly. Abdominal ultrasound revealed severe unilateral hydronephrosis associated with hydroureter in both ferrets. No obvious cause of obstruction was identified. Biochemical results were unremarkable in both patients. Hydronephrosis was investigated through CT scans, revealing Type 1 circumcaval ureter in both ferrets. Section and relocation of the right ureter by uretero-vesical anastomosis was performed in one ferret. This ferret died 48 hours later following a nephrectomy performed due to persistent hydronephrosis. The second cas underwent right nephrectomy andd ureter resection due to severe hydronephrosis and stenosis of the circuncaval segment. This ferret has remained healthy on followup with no abnormalities found in biochemistries or ultrasound examination.Conclusion and case relevanceFindings suggest that circumcaval ureter should be suspected in ferrets with unilateral hydronephrosis and associated hydroureter without any identified cause of obstruction on abdominal ultrasonography. It should be confirmed with CT scan and/or urography and treated surgically.     

Aleutian Disease of Mink: I. Evidence of its Viral Etiology *

A suspension of tissues from field cases of Aleutian disease was used successfully to reproduce the disease in Aleutian mink. Similarly, suspensions of diseased tissues from the experimentally infected mink were used to transmit the agent of Aleutian disease to both Aleutian mink and standard dark mink. Seitz and millipore filtrates prepared from these tissue suspensions were also infective; a suggestion that the etiologic agent is a virus. Genetic factors and hypersensitivity are discussed as possibly contributing to development of the disease.     

水貂阿留申病的研究进展

水貂阿留申病(Aleutian disease of mink,ADM)是由水貂阿留申病细小病毒(Aleutian mink disease parvovirus,AD-MV)引起的一种慢性、进行性传染病,一直是危害世界养貂业健康发展最重要的疫病之一。到目前为止,还没有疫苗可成功用于ADM的预防,也没有特异有效的治疗方法,唯一可行的防治方法就是通过多次特异性检疫,淘汰病貂,净化貂群。笔者对阿留申病的病原学、发病机制、防治措施等方面进行概述,为临床防治水貂阿留申病提供了理论基础。     

Preparation of Genetic Engineering Diagnostic Antigen of Mink Aleutian Disease

To develop a new method of Aleutian disease (AD) diagnostic antigen production,we used Bac-to-Bac expression system in this study.Firstly,Aleutian disease virus (ADV) genome was extracted and ADV VP2 gene was amplified by PCR method.Then Bacmid-VP2 was constructed and transfected into insect cell Sf9 by liposomes to construct AcMVPV-VP2.Secondly,the VP2 protein was observed by electromicroscope and antigency was detected by Western blotting.At last,the activity of recombinant protein was inspected by countercurrent immunoelectrophoresis.The results showed that the expressed recombinant VP2 protein could react with ADV positive serum and form virus like particles.Compared with the commercial diagnostic antigen,the coincidence rate of recombinant antigen was 100%.This method could be a candidate for AD diagnostic antigen production.     

水貂阿留申病基因工程诊断抗原的制备

本研究旨在建立一种生产水貂阿留申病(Aleutian disease,AD)诊断抗原的新方法。试验提取水貂阿留申病毒(Aleutian disease virus,ADV)的基因组,PCR扩增ADV核衣壳蛋白VP2基因,构建重组表达质粒Bacmid-VP2,脂质体介导其转染昆虫细胞Sf9获得重组杆状病毒AcMVPV-VP2。电镜下观察表达的VP2蛋白,Western blotting检测目的蛋白的反应原性。以传统接毒方法生产的AD诊断抗原作对照,通过对流免疫电泳试验检测表达蛋白的生物学活性。结果表明,表达的重组VP2蛋白在电镜下组装成病毒样颗粒且能与ADV阳性血清发生反应。与商业诊断抗原相比,重组抗原诊断AD的阴阳性的符合率为100%。该方法可成为生产AD诊断抗原的替代方法。