Mesenchymal chondrosarcoma in a young German shepherd dog

An 18-month-old, entire male German shepherd dog was presented with signs indicative of a caudal abdominal space-occupying mass. A needle-core biopsy of this mass failed to establish a definitive diagnosis, but identified a prominent round-cell component. The dog's condition worsened and euthanasia was performed on humane grounds. Histopathology of the mass revealed a mesenchymal chondrosarcoma.     

Presence of cervical vertebral malformation in Dobermann puppies and the effects of diet and growth rate

OBJECTIVE: To investigate the relationship between diet, growth rate and the presence of caudal cervical malformation in Doberman puppies. DESIGN: A prospective study of 15 Dobermann puppies from three unrelated litters, aged from 0 to 16 weeks. PROCEDURE: The growth rate in terms of body weight gain and increase in ulna length were measured weekly for all puppies. In addition the nutritional quality of the diets was assessed. Radiographs of the cervical spine were taken at 6 and between 12 and 16 weeks of age and examined for the presence of caudal cervical vertebral malformation. A mixed model for repeated measures data was used to investigate the relationship between the growth rate of the puppies and the fixed effects age, dam, diet, gender and presence of caudal cervical malformation. RESULTS: Five of the puppies had changes consistent with caudal cervical malformation. The diets fed were either balanced or transiently deficient in protein, calcium, phosphorus and/or magnesium. There was no significant association between growth rate and the variables dam, gender and the presence of caudal cervical vertebral malformation. There was no significant association between diet and increase in ulna length, but a trend existed between body weight gain and the feeding of a balanced diet (P = 0.0672). CONCLUSION: Caudal cervical vertebral changes can be detected radiographically as early as 6 weeks of age in some Dobermann puppies. A balanced diet and growth rate are not significant factors in its initial development.     

Mycobacterium paratuberculosis detection in bovine feces is improved by coupling agar culture enrichment to an IS900-specific polymerase chain reaction assay.

The feasibility of coupling an agar culture enrichment step with gene amplification (ACE-PCR) as a means to improve turnaround time and detect Mycobacterium paratuberculosis (Mpt) in the presence of contaminants was investigated. Fecal samples from 463 Pennsylvania dairy cows were cultured in duplicate sets. One replicate from each set was processed and interpreted according to standard culture (SC) protocol, whereas cultures from the second replicate were harvested at 6 weeks postinoculation; DNA extracts from the harvested material were evaluated by a polymerase chain reaction (PCR) test for the Mpt-specific IS900 gene. One hundred seventy-six of 463 culture sets were positive by either method. One hundred sixty-five of these (94%) were ACE-PCR positive, and 151 (86%) were positive by SC. Eleven SC-positive samples were ACE-PCR negative, and 9 ACE-PCR-positive samples were negative by SC; these discrepancies could be a consequence of a low organism burden (< or = 5 organisms/g) or slow growth rate of Mpt in cultures of these samples. One hundred thirty-nine of 463 culture sets (30%) were reported as inconclusive because of culture contamination according to SC protocol; 16 of these (11.5%) were ACE-PCR positive. Seventy-four ACE-PCR-positive sets (42% of all positives) were negative or inconclusive by SC at 6 weeks postinoculation. Agar culture enrichment prior to IS900 PCR testing significantly improves Mpt culture turnaround time and sensitivity.     

Microsatellite variation between an African and five European taurine breeds results in a geographical phylogenetic tree with a bison outgroup

Genetic variation is being used extensively for individual identification and linkage analysis, and may be useful for interpopulation studies. Previously, blood groups and biochemical variants in blood cell and serum proteins have been used to study (evolutionary) relationships in mammals. But genetic divergence and gene flow among closely related populations are difficult to measure with these classical markers because their mutation rate is so low that new mutations have not had sufficient time to appear and become fixed. So they have a small number of alleles and a relatively low level of heterozygosity. These markers are now replaced by DNA markers, mostly microsatellites. These microsatellite loci are useful genetic markers at which alleles differ in length due to differences in the number of short sequence motifs arranged adjacent to one another. They are abundantly distributed throughout the mammalian genome. They have a large number of alleles, a high level of heterozygosity and are inherited in true Mendelian fashion. These characteristics make them valuable for parentage control, linkage analysis, genome mapping and phylogenetic studies. In terrestrial vertebrates with limited mobility, genetic differentiation often increases with the distance between populations or corresponds to the extent of geographic and habitat barriers (R oy et al. 1994). Investigations of short tandem repeats yield a considerable volume of genetic data regarding the similarities and divergence times of different cattle populations. Microsatellite markers are suitable for the estimation of these parameters as they are not generally subject to direct selection and environmental influences. Computation of genetic distances based on data from several loci can be used to evaluate the taxonomic relationship between populations. The aim of this study was to estimate the relative genetic variability between Belgian cattle breeds and to reconstruct the evolutionary relationship among them, also using two small genetically isolated cattle-like populations.     

Duration of immunity in foxes vaccinated orally with ERA vaccine in a bait.

Red foxes (Vulpes vulpes) vaccinated orally with the ERA strain of rabies vaccine in a bait were challenged after 83 mo. Ten of 11 foxes that had seroconverted following vaccination resisted challenge with a virulent rabies virus which produced clinical signs of rabies in 6 of 6 unvaccinated foxes. Five of 11 vaccinated animals retained titers of rabies virus neutralizing antibody throughout the period. Although 6 of 11 had no detectable antibody at the time of challenge, 5 of these 6 resisted challenge and had an anamnestic response, as indicated by elevated titers of antibody when measured at day 77 postchallenge. These results show that foxes can be immunized successfully with a single oral dose of ERA vaccine, probably with protection against a lethal rabies challenge, for at least 7 y.     

Pharmacokinetics of diacetoxyscirpenol in cattle and swine: effects of halothane

In swine and cattle given 0, 0.1, or 0.5 and 0, 0.5 mg of diacetoxyscirpenol (DAS)/kg of body weight, IV, respectively; DAS had a large volume of distribution and total body clearance. The shortness of the interval between halothane and DAS exposures significantly (P greater than 0.05) decreased DAS biotransformation. Urinary excretion of DAS as a parent compound was not an important route of elimination. In swine and cattle, DAS was transformed by sequential deacetylation to monoacetoxyscirpenol and scirpentriol.     

Copper toxicosis in cattle fed chicken litter

Cattle from 2 herds developed copper toxicosis after the ingestion of chicken litter. The affected animals were adult Holstein cows and crossbred steers that ate 9 to 16 kg of litter/day. These cattle developed a sudden onset of weakness, depression, anorexia, icteric mucous membranes, and dark reddish brown urine. Liver copper concentrations in 2 cattle (1 from each herd) were 436 and 730 ppm. Results of copper analyses of chicken litter ranged from 620 to 920 ppm. Sodium molybdate and sodium thiosulfate were added to the ration of the dairy herd. Two cows with clinical signs of copper toxicosis recovered after being given additional sodium molybdate and thiosulfate supplements, orally.