Objective—To analyze factors associated with interdog household aggression and determine treatment outcomes.
Design—Retrospective case series and survey.
Animals—38 pairs of dogs with interdog household aggression. Each pair of dogs was considered 1 case.
Procedures—Records of dogs with interdog household aggression that were examined during initial or follow-up consultations at a veterinary teaching hospital from December 5, 2006, to December 5, 2007, were analyzed for clinical features. Data regarding outcome, owner compliance, and efficacy of recommended treatments obtained by use of a follow-up survey were evaluated.
Results—Most cases (30/38 [79%]) of interdog household aggression involved same-sex pairs; 26 of 38 (68%) cases involved 1 female or a pair of females. Instigators and recipients of aggression were clearly identified in 27 of 38 (71%) cases; most instigators were the younger of the pair (20/27 [74%]) or were newer additions to the household (19/27 [70%]). Fight-eliciting triggers included owner attention, food, excitement, and found items. Some dogs had risk factors for behavior problems such as a history of living in multiple households (21/51 [41%]), adoption after 12 weeks of age (20/51 [39%]), or being acquired from a shelter (17/51 [33%]). Effective treatment recommendations included implementing a so-called nothing-in-life-is-free program, giving 1 dog priority access to resources, and administering psychotropic medication. Frequency and severity of fighting were significantly reduced after consultation. Owners reported a 69% overall improvement following treatment.
Conclusions and Clinical Relevance—Most treatment strategies were considered effective. Consistency and predictability of social interactions are essential in resolving interdog household aggression.
Objective—To compare heat generation during insertion, pullout strength, and associated microdamage between a self-tapping positive profile transfixation pin (STTP) and nontapping positive profile transfixation pin (NTTP).
Sample Population—30 pairs of third metacarpal bones (MC3s) from adult equine cadavers.
Procedures—One MC3 of each pair was assigned to the STTP group; the other was assigned to the NTTP group. The assigned pin was inserted into the diaphysis in a lateral to medial direction. Bone temperature increase during pilot-hole drilling and pin insertion was recorded at 1 mm from the final thread position with wire thermocouples at cis and trans cortices. Resistance to axial extraction before and after cyclic loading was measured in a material testing device, and microstructural damage caused by transfixation pin insertion was assessed with scanning electron microscopy.
Results—The STTP group developed a significant increase in bone temperature, compared with the NTTP group. No significant difference was found between the mean maximal pullout strength of the STTP and the NTTP in both non–cyclic-loaded and cyclic-loaded groups. Microdamage to the bone-pin interface was lower when the STTP versus the NTTP was used, but more bone debris was apparent after inserting the STTP.
Conclusion and Clinical Relevance—Because of the significant increase in temperature generation and debris accumulation despite similar pullout strengths and lesser microfracture formation, the STTP likely poses a higher risk of bone necrosis and potential loosening than the NTTP. This might be corrected by redesign of the tapping aspect of the STTP.