A retrospective case series determined the prevalence of appendicular osteosarcoma (OSA) in Greyhounds compared with other breeds and identified potential intrinsic risk factors associated with development of OSA.

Medical records of 179 dogs in which primary appendicular OSA had been diagnosed between 1996 and 2005 were reviewed. Prevalence and crude odds ratios for OSA were calculated for various breeds by comparison with a reference population of mixed breed dogs. Age and sex were examined as potential risk factors for the 3 breeds with highest prevalence.

Breed prevalence of OSA was highest for Greyhounds (21/339 [6.2%]), followed by Rottweilers (51/969 [5.3%]) and Great Danes (13/297 [4.4%]); all 21 Greyhounds with OSA were identified as having retired from racing. Sex was not identified as a risk factor for OSA in these breeds, but in all 3 breeds, risk of OSA increased with age. Greyhounds were significantly older at the time of OSA diagnosis (mean, 9.9 yrs) than were Rottweilers (8.3 yrs) and Great Danes (7.8 yrs). Rottweilers and Great Danes were more likely to have OSA involving the forelimbs than the hind limbs. The most frequent lesion sites for all 3 breeds were the proximal end of the humerus and distal end of the radius. The proximal end of the femur was also a common site for the Greyhounds.

Conclusions and Clinical Relevance Results of the present study suggested that Greyhounds, Rottweilers, and Great Danes have an increased risk of developing OSA, compared with mixed-breed dogs.

Reference: Rosenberger et al, J Am Vet Med Assoc 231:1076-1080, 2007.

A hemorrhagic diathesis due to neonatal alloimmune thrombocytopenia occurred in a sow herd consisting of Large White X Landrace females. Colostrum, containing maternal antibodies incompatible with platelet antigens inherited from the sire [14 platelet antigens have been recognized to date in swine], was ingested and absorbed by the piglets. Six piglets were affected and displayed signs of lethargy and depression with petechiation, ecchymosis, and severe bruising of the skin. All 6 piglets died or were euthanized by 3 days of age. This case study serves as a reminder of the potential for neonatal thrombocytopenia in swine when the sire and dam have incompatible platelet antigens.

Reference: Forster, Can Vet J 48:855-857, 2007.