Thyroxine concentrations are elevated in mares which continue to exhibit estrous cycles during the nonbreeding season

In two successive years, the pattern of secretion of thyroxine was compared in seasonally anestrous mares and a subpopulation of mares that exhibited estrous cycles during the nonbreeding season. Blood samples were collected two or three times per week between October and April from a total of 15 mares that exhibited estrous cycles during the nonbreeding season and 21 anestrous mares. Monthly mean concentrations of thyroxine during the period from October through April were greater (p<0.05) in cycling versus anestrous mares. However, it remains to be determined whether continuation of estrous cycles during the nonbreeding season and elevated concentrations of thyroxine are causally related.     

Lymphocyte Populations in Joint Tissues from Dogs with Inflammatory Stifle Arthritis and Associated Degenerative Cranial Cruciate Ligament Rupture

Objective: To evaluate lymphocyte populations in stifle synovium and synovial fluid of dogs with degenerative cranial cruciate ligament rupture (CCLR). Study Design: Prospective clinical study. Animals: Dogs (n=25) with stifle arthritis and CCLR, 7 dogs with arthritis associated with cartilage degeneration (osteoarthritis [OA]), and 12 healthy Beagle dogs with intact CCL. Methods: Arthritis was graded radiographically in CCLR dogs. After collection of joint tissues, mononuclear cells were isolated and subsequently analyzed using flow cytometry for expression of CD3, CD4, CD8, and CD21. Results: The proportions of CD4⁺ T helper lymphocytes, CD8⁺ cytotoxic T lymphocytes, and CD3⁺CD4^?CD8^? T lymphocytes were increased in synovium from dogs with CCLR compared with synovium from healthy Beagle dogs (P<.05). The proportion of CD3⁺CD4^?CD8^? T lymphocytes in synovial fluid was increased in dogs with CCLR compared with dogs with OA (P<.05). In dogs with CCLR, the proportion of CD3⁺CD4^?CD8^? T lymphocytes in synovial fluid was inversely correlated with radiographic arthritis (S_R=?0.68, P<.005). Conclusion: Lymphocytic inflammation of stifle synovium and synovial fluid is an important feature of the CCLR arthropathy. Lymphocyte populations include T lymphocytes expressing CD4 and CD8, and CD3⁺CD4^?CD8^? T lymphocytes. Presence of CD3⁺CD4^?CD8^? T lymphocytes was associated with development of stifle synovitis. Further work is needed to fully identify the phenotype of these cells.     

Review of kinematic analysis in dogs

Objective gait analysis techniques aid investigators in the study of motion. Kinematic gait analysis techniques that objectively quantitate motion are valuable tools used to understand normal and abnormal motion in domestic animals. Recent advances in video technology have made the study of motion more readily accessible. Available systems can document gait in two or three dimensions (2D or 3D, respectively). Knowledge of fundamental gait analysis concepts is critical to generating meaningful data. The objective of this report is to review principles of kinematic data collection and analyses, with a focus on differences between 2D and 3D systems.