BACKGROUND: Polycystic kidney disease is the most prevalent inherited genetic disease in Persian cats, which is caused by mutations in PKD1 and PKD2 genes. Due to the accumulation of fluids inside the cysts and their pressure on the renal parenchym, the patient is prone to developing symptoms of chronic renal failure.OBJECTIVES: The present study aimed to compare ultrasonography and molecular tests in diagnosis of autosomal dominant polycystic kidney disease.METHODS: This study was performed on 97 Persian cats, including 46 male and 51 female cats, with an average age of 6 years (minimum 2 months and maximum 14 years). All the cats were evaluated for the presence of disease using ultrasound and molecular methods.RESULTS: Among 97 females, 32 (33 %) were found to be positive for PKD on the basis of presence of anechoic cysts. In molecular tests, all the cases with cysts in the ultrasonography had mutation in PKD1 gene and 13 cases (13 %) without cysts in ultrasonography were diagnosed to be positive through molecular technique. Among 97 studied cats, 45 (46 %) showed mutated genes. The degree of agreement between the two methods of ultrasonography and PCR was determined by calculating Kapa 0.725 (Cl: 0.592-0.895). The sensitivity and specificity of the ultrasonography were calculated to be 77.11 % and 100 %, respectively.CONCLUSIONS: Imaging and molecular methods were utilized to diagnose the disease. The more frequent use of the molecular methods for the diagnosis of the disease compared to the use of ultrasound could be attributed to the higher sensitivity of the molecular technique, the small size of the cysts, the low number of cysts, the low age of the animal, and the presence of cysts in the medula of the kidney. Therefore, the molecular method could be recommended for screening the disease in the early stages. It can also be employed in breeding programs and the removal of cats with this mutated gene.

HISTORY: Suspensory ligament injury associated with avulsion or crescent fracture of third metacarpal or metatarsal bone is a common injury in racehorses. Lameness is known to be the most common clinical sign of these horses. CLINICAL FINDING: The present article investigated two avulsion fractures in the third metacarpal bone in 2.5-year-old mare and stallion, which had chronic lameness with a vague origin and disability of weight bearing in left forelimbs. DIAGNOSTIC TESTS: Following radiography and ultrasonography examinations, suspensory ligament injury and subsequently avulsion fracture in the proximal third of metacarpal bones in left forelimb were approved. FINAL EVALUATION: In radiography, radiolucent lines associated with fragmented segments (about 2×6×8 mm) in mare and (about 2×4×6 mm) in stallion  in the proximal part of  the third metacarpal bone were indicative of an avulsion or crescent fracture at the origin of the suspensory ligament. Furthermore, in ultrasonography compatible with radiographic findings, an echogenic-fragmented fracture in the proximal part of the third metacarpal bone and a local area of decreased echogenicity was diagnosed as desmopathy of suspensory ligament.