Diagnostic imaging descriptions and prevalence of presumed phrenic lymph nodes in dogs.

The phrenic lymph node (PLN) has been described in bovine, equine, and feline anatomic references but descriptions in canine anatomic references are currently lacking. Authors have observed a well-defined, soft tissue attenuating, contrast-enhancing structure in a location consistent with previous anatomic descriptions of the PLN in dogs that underwent thoracic CT for neoplastic staging. The aims of this two-part, retrospective/prospective, anatomic, prevalence study were (1) to describe the presence of a soft tissue structure close to the thoracic caudal vena cava, defined as the presumed PLN, in a series of dogs that underwent CT as part of the staging for metastatic disease; (2) to confirm the lymphatic origin of the presumed PLN in a dog through postmortem examination; (3) to assess the prevalence of the presumed PLN in a population of dogs that underwent thoracic CT or MRI for different clinical purposes; and (4) to assess the possibility to visualize the presumed PLN with ultrasonography. The lymphatic origin of the presumed PLN was confirmed by postmortem examination in one dog. The presumed PLN was visible in 29 of 777 canine CT examinations (prevalence 3.7%). The presumed PLN was not visible in 9 of 10 prospectively recruited ultrasound cases. Most dogs with visible presumed PLNs were large-medium breeds that were presented for neoplastic staging purposes. Findings indicated that a structure consistent with the previously reported anatomic features of PLN in cattle, horses, and cats may be detected with a low prevalence in canine CT and MRI examinations.

Safety assessment of equine allogeneic tenogenic primed mesenchymal stem cells in horses with naturally occurring tendon and ligament injuries.

Background: Mesenchymal stem cells provide a valuable treatment option in orthopedic injuries in horses. Objectives: The aim of this study was to evaluate the hematological, biochemical, immunological and immunomodulatory parameters following intralesional treatment with tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells (tpMSCs) in client-owned horses with naturally occurring superficial digital flexor tendon (SDFT) and suspensory ligament (SL) injuries. Methods: The immunogenicity and immunomodulatory capacities of tpMSCs were assessed in a modified mixed lymphocyte reaction, including peripheral blood mononuclear cells (PBMCs) of 14 horses with SDFT and SL injuries after treatment with tpMSCs. In a second study, 18 horses with SDFT and SL injuries received either an intralesional injection with tpMSCs (n = 9) or no treatment (n = 9). Results: The tpMSCs did not provoke a cellular immune response (p < 0.001) and were able to immunomodulate stimulated T lymphocytes (p < 0.001) in vitro. Therapeutic use of tpMSCs did not result in relevant hematologic or biochemical abnormalities. Main limitations: Both studies had a small sample size. No statistical analyses were performed in the second study. Fibrinogen was only analyzed in a single horse prior to treatment. Conclusion: Co-incubation of tpMSCs and PBMCs of horses that have been previously exposed to tpMSCs did not elicit a cellular immune response and tpMSCs were able to immunomodulate stimulated T lymphocytes. Intralesional treatment with tpMSCs did not provoke abnormal changes in hematological and biochemical parameters.

The utilization of the Vezzoni modified Badertscher distension device in breeding programs: Heritability estimates and effect on the hip dysplasia prevalence.

Canine hip dysplasia (CHD) is a common orthopedic condition, influenced by both genetic and environmental factors. While current breeding programs often rely on ventrodorsal hip-extended (VDHE) radiographs, it is known they fail to accurately assess hip joint laxity. Therefore additional laxity-oriented diagnostic techniques have been developed. This study aims to evaluate the effectiveness of the Vezzoni modified Bädertscher distension device (VMBDD) technique, which quantifies hip joint laxity with the laxity index (LI), as a screening tool in two breeding programs. Data from a Belgian population of assistance dogs (population A) and a French population of guide dogs (population B) were analyzed. The heritability estimates of the LI, estimated using Bayesian statistical methods, were high in both populations (0.83 in population A and 0.82 in population B). Improved screening of parents by combining the VMBDD technique with the VDHE, significantly decreased LI and the prevalence of CHD in their offspring. In population A, when two parents were screened with the VMBDD compared to one, there was an average LI decrease of 0.03 (P<0.05). In population B, when one or both parents were screened with the VMBDD compared to none, the average LI decrease was 0.04 (P< 0.05) and 0.05 (P<0.01), respectively. In population A, screening both parents with the VMBDD in addition to the VDHE, resulted in 82.7% (P< 0.05) lower odds of CHD compared to screening only one parent. In population B, screening one parent led to 72.3% (P<0.05) lower odds of CHD compared to none of the parents being screened. In population B, when both parents were screened with the VMBDD, not a single case of CHD was observed in the puppies. In conclusion, based on these results, the VMBDD technique has the potential to drastically reduce CHD prevalence and is as such an excellent tool for breeding programs.