Placement of ureteral stents in three rabbits for the treatment of obstructive ureterolithiasis.

Management of ureteral obstruction with stenting is often associated with a lower rate of complications than ureterotomy in domestic carnivores, but this treatment has not been previously evaluated in rabbits. Three rabbits (7, 6 and 10 years old) were diagnosed with unilateral obstructive ureterolithiasis associated with hydronephrosis and hydroureter on abdominal ultrasound. Decreased overall renal function was confirmed in all three cases. Ureteral stents were placed retrogradely via cystotomy without complication in two cases and anterogradely via nephrostomy in the third case. Survival after stent placement was 30, 3 and 8 months, with encrustation of the stent and re-obstruction occurring 18, 1 and 6 months after stent placement in successive cases. Ureteral stenting can be considered for short-term management of ureterolithiasis in rabbits to improve renal function and maintain quality of life. Ultrasound or radiographic monitoring is recommended to detect encrustation of the stent. Studies comparing ureteral stenting to ureterotomy in rabbits are needed to determine the effectiveness of these techniques.

Morphological variation in the horse: defining complex traits of body size and shape.

Horses, like many domesticated species, have been selected for broad variation in skeletal size. This variation is not only an interesting model of rapid evolutionary change during domestication, but is also directly applicable to the horse industry. Breeders select for complex traits like body size and skeletal conformation to improve marketability, function, soundness and performance in the show ring. Using a well-defined set of 35 measurements, we have identified and quantified skeletal variation in the horse species. We collected measurements from 1215 horses representing 65 breeds of diverse conformation such as the American Miniature, Shetland Pony, Arabian Horse, Thoroughbred, Shire and Clydesdale. Principal components analysis has identified two key dimensions of skeletal variation in the horse. Principal component 1 is positively correlated with every measurement and quantifies overall body size. Principal component 2 captures a pattern of bone widths vs. lengths and thus quantifies variation in overall bone thickness. By defining these complex skeletal traits, we have created a framework for whole genome association studies to identify quantitative trait loci that contribute to this variation.