Ultrastructural and transmission evidence of Sarcocystis cruzi associated with eosinophilic myositis in cattle.

Skeletal muscle, diaphragm, tongue, esophagus and heart of beef carcasses that were condemned for eosinophilic myositis and those that were unaffected were collected at an abattoir in Colorado and studied to determine the involvement of Sarcocystis spp. All affected carcasses contained similar granulomatous lesions with adjacent infiltrations of leukocytes. Intact or fragments of sarcocysts were found within 32 of 363 granulomas, and whole sarcocysts were present in nearby unaffected muscle cells. Light and electron microscopic examinations revealed that sarcocysts, affected or unaffected by cellular response in condemned carcasses, as well as those found in unaffected carcasses, were consistent with those of S. cruzi. Transmission experiments confirmed that S. cruzi were present in all carcasses, and that dogs, but not cats, were the definitive hosts. The results of pepsin-HCl digestion assays showed that unaffected carcasses that were approved for human consumption generally contained more infective parasites than carcasses that were condemned for eosinophilic myositis. This study provides evidence to support the suggestion that dogs, rather than cats, and unaffected rather than eosinophilic myositis-affected carcasses, have greater potential for contributing to the perpetuation of eosinophilic myositis in the cattle industry.     

Fungi associated with bovine abortion in the northern plains states (USA).

Mycotic infection was diagnosed in 6.8% of 6,858 cases of bovine abortion and stillbirth examined during a 9-year period. Aspergilli were associated with approximately 5% of all abortion cases and 71% of 446 cases that were cultured for fungi and diagnosed as mycotic abortion. Aspergillus fumigatus was the most frequent isolate (62%), followed by A. terreus (6.7%), Emericella (Aspergillus) nidulans (3.0%), A. flavus (2.9%), and E. rugulosus (less than 1.0%). Zygomycetes (Absidia, Mortierella, Rhizomucor, Rhizopus) accounted for 21% of the cases. Pseudallescheria boydii and yeasts (Candida, Torulopsis) were each identified in 2% of the cases. Fungi that uncommonly cause infection accounted for 2% of the cases and included Curvularia geniculata, Exophilia jeanselmei, Hendersonula toruloidea, Lecythosphora hoffmannii, Talaromyces flavus var. flavus (Penicillium vermiculatus), T. (Penicillium) thermophilus, and Wangiella dermatitidis. About 10% of the mycotic cases were mixed fungal infections involving A. fumigatus (87%), A. flavus (12.5%), or E. nidulans (12.5%) coexisting with Absidia corymbifera (72%), Rhizomucor pusillus (4.3%), or Rhizopus arrhizus (4.3%). In each mixed infection, both septate and nonseptate hyphae were observed in placental tissues. Twelve percent of the mycotic abortion cases were diagnosed by histologic examination alone because isolation attempts were negative or only formalin-preserved tissues were available.     

Pestivirus is a common contaminant in maedi-visna and caprine arthritis-encephalitis virus stocks.

Eight different laboratory stocks of maedi-visna or caprine arthritis-encephalitis virus were examined for the presence of pestiviruses by a fixed-cell immunoperoxidase assay with polyclonal and monoclonal antibodies. All of the viral stocks examined were found to contain noncytopathic pestivirus contaminants. The panel of monoclonal antibodies could not type the isolates as being more related to bovine virus diarrhea virus or border disease virus. However, the results did indicate that all isolates were not the same, except for two from the same laboratory where the source of pestivirus contamination may have been common.     

Assessment of the quality of tests for the detection of antibodies to Aujeszky's disease virus glycoprotein gE in a target population by the use of receiver operating characteristic curves

The performance of tests for the detection of antibodies to Aujeszky's disease virus glycoprotein E (ge) in a target population was evaluated by constructing and analysing receiver operating characteristic (roc) curves. These curves assess the discriminating ability of a test over the entire range of test signals. The advantages of applying the analysis to a sample of the target population (all commercial pigs in the Netherlands), as compared to using a panel of test sera, are that the estimates of sensitivity and specificity, the comparisons between tests and the choices of the cut-off values are all relevant for the target population. The results of a gE-elisa in colostrum (test A) and in a single droplet of whole blood (test B) were compared with the results obtained with the same elisa in serum (gold standard). The area under the ROC curve, which is a quantitative measure of test performance, was significantly (P<0·01) smaller with test A than test B or the gold standard, indicating that test B performed better than test A. No significant difference was observed between test B and the gold standard.     

The effect of digital lesions and floor type on locomotion score in Dutch dairy cows

This study describes the effects of floor system, digital dermatitis (DD) and interdigital dermatitis and heel-horn erosion (IDHE) on locomotion performance in 225 dairy cows of 12 commercial dairy herds. Nine herds were kept in cubicle houses with concrete passageways (either solid, slatted, or grooved concrete) and three herds were kept in straw yards. Animals were at most five times examined at monthly intervals for lesion severity of DD and IDHE and for locomotion score. Locomotion score was rated on a scale ranging from 1 to 5 (from normal to severe) and disturbed locomotion (lameness) was defined as a score > or =3. A logistic regression model was used to analyze the 943 observations using lameness (yes/no) as outcome variable. The proportion of observations scored as lame (locomotion score > or =3) increased from 18% 1 month after trimming to 29% at 4 months after trimming. Severe lesions of DD and IDHE were associated with a significantly higher proportion of lame cows. The proportion of animals with disturbed locomotion increased from 16% to 40% as the severity of DD increased and from 17% to 30% with increasing severity of IDHE lesions. Locomotion performance highly differed between the cubicle house and straw yard group. Only 1% of all gaits in straw yard cows were scored as lame, while in cubicle housed cows these percentages varied from 24% to 46% with grooved floors showing the highest average locomotion score. Due to the extreme low incidence of lameness in straw yards, the statistical analysis had to be restricted to observations on concrete floors (n=744). The logistic regression model with lameness (yes/no) as dependent variable and random effects of cow and herd resulted in Odds Ratios for severe DD and IDHE of, respectively, 3.2 and 3.2, both significantly larger than unity. Cows housed at grooved concrete floors showed the highest OR of 6.5 compared to solid concrete floors. Recovery of lameness was poor as disturbance in gait lasted several months.     

Prevalence of Bovine Viral Diarrhoea Virus antibodies among the industrial dairy cattle herds in suburb of Mashhad-Iran

Mashhad is a major dairy production in Iran. The subject of this study was to survey the seroprevalence of Bovine Viral Diarrhea Virus (BVDV) infection using an indirect Enzyme-linked immunosorbent assay (ELISA) test in industrial dairy cattle herds in suburb of Mashhad-Iran. Totally, 141 serum samples were tested. None of the herds had been vaccinated against BVDV. Commercial indirect ELISA kit was used. The herds divided to 3 sizes as cow population. They were included: small, medium and large herds. Data were analyzed using Chi-square test. Ninety-seven (68.79%) cows were ELISA seropositive. However, the true BVDV seroprevalence was 72.25%. All of the herds were antibody positive against BVDV. The prevalence ranged from 66 to 100% within the herds. There were no significant differences between the presence of antibodies to BVDV and the herd size (P > 0.05). The prevalence in animals lower than 2 years old differed significantly with cows higher than 2 years old (P < 0.05). According to the results, it is concluded that it is likely the presence of persistently infection (PI) animal(s) within the herds in suburb of Mashhad-Iran, which is responsible for the presence antibody.     

Eosinophilic leukaemoid reaction in a dog

A haematological disorder in a dog characterised by a massive leucocytosis, mainly composed of eosinophils and their precursors is reported here. The normal composition of cells in the bone marrow was displaced in favour of the eosinophils and their precursors. No apparent cause for the pronounced eosinophilia could be determined by clinical, haematological, clinical-chemical, radiological or pathological examinations. A diagnosis of eosinophilic leukaemoid reaction was suggested as the criteria for the diagnosis of eosinophilic leukaemia in the dog but this was not firmly established.