Use of external nasal strip influences alveolar cell population of horses after exercise / Uso de fita nasal influencia a população de células alveolares em equinos após exercício

The nasal strip is widely used in horses during exercise, but effects of using a nasal strip are controversial and little is known about its effect on horses undergoing endurance events. The aim of this study was to determine whether the use of nasal strips influences alveolar cell population assessed by bronchoalveolar lavage (BAL), tidal volume, and nasal airflow rate. Six Arabian horses were subjected to two low intensity tests on a treadmill, with and without application of a commercial external nasal strip. Tidal volumes and airflow rates were measured during the test; two hours after the test, BAL was performed to assess cytology of pulmonary secretions. The lavage fluid showed increased neutrophil count after exercise in animals with the nasal strip (P<0.05). This suggests that turbulence of airflow through the nasal cavity may have diminished with nasal strip use, thus allowing larger particles to be deposited more distally in the respiratory system, inducing a more intense neutrophilic response. No differences in tidal volumes or airflow rates were observed between groups (with or without nasal strips) during the test (P>0.05). The use of nasal strips seems to influence alveolar cell population during and after exercise in horses after low intensity exercise tests. Further studies are needed to verify whether alveolar cell population is related to poor exercise performance in horses.(AU)

A fita nasal é amplamente utilizada em equinos durante o exercício, porém seus resultados são controversos e pouco conhecidos em animais que disputam provas de resistência. O objetivo deste trabalho foi verificar se o uso da fita nasal influencia a população de células alveolares por meio de lavado broncoalveolar, volume corrente e fluxo de ar nasal. Foram utilizados seis equinos da raça Árabe, que realizaram dois testes de longa duração em esteira, sendo um teste com a fita e outro sem a fita nasal. Fluxo e volume respiratório foram mensurados durante o teste; duas horas após o término do exercício, foi realizado lavado broncoalveolar para realização de citologia da secreção pulmonar. Foi verificada maior porcentagem de neutrófilos após o exercício nos animais que se exercitaram com a fita nasal (P<0,05), indicando que o turbilhonamento na passagem do ar através da cavidade nasal pode ter diminuído, permitindo que partículas maiores se depositassem em porções mais distais do sistema respiratório, induzindo uma resposta neutrofílica mais intensa. Não houve diferenças entre os parâmetros ventilatórios analisados entre os animais quando correram com ou sem a fita nasal (P>0,05). O uso da fita nasal parece influenciar alguns parâmetros, durante e após o exercício, em animais que realizam provas de longa duração. Outros estudos devem ser realizados para verificar se essa influência pode melhorar o desempenho desses animais em exercícios predominantemente aeróbicos.(AU)

Arthroscopic evaluation of the synovial membrane and its relationship with histological changes and biomarkers in equine joint disease.

The synovial membrane (SM) presents itself with distinctive characteristics during arthroscopic procedures in cases of osteoarthritis (OA) as well as osteochondritis dissecans (OCD) in horses. Most of the arthroscopic findings of the SM are limited to a description of a nonspecific inflammation state. In the present study, the macroscopic and histological aspects of the SM in OA and OCD horses were compared to those of healthy horses. The expression of interleukin (IL) in SM was also investigated. Besides, the concentrations of ILs and keratan sulfate (KS) in the synovial fluid (SF), and the molecular weights of the SF hyaluronic acid (HA) were also determined and correlated to the macroscopic and histological aspects of SM. This study included 10 healthy horses (control group), 12 horses with OA, and 12 with OCD. Macroscopic scores of the SM were higher in the OA group in comparison to the control and OCD groups. However, histological scores between OA and OCD were not different, and both were higher than the control group. Only in the OA group, there was a correlation between macroscopic and histological aspects of the SM, especially between volume and quantity of villi with perivascular inflammatory cells and synovial proliferation. The OA group has shown decreased expression of IL-10 in the SM, lower IL-10 and KS, and higher IL-1ß and IL-6 in the SF in comparison to the control and OCD groups. There was a significant negative correlation between the macroscopic aspect of the SM and the molecular weights AH in the OA group. There was no correlation between the macroscopic aspect of the SM and all dosages in the OA and OCD group. In the OA joints, the evaluation of the shape of the SM during arthroscopy promotes a better indicator for joint inflammatory or tissue repair processes, while in the osteochondritic joints, investigation of the histological aspects are recommended to rule out an incipient OA development process. Both are helpful and should be considered to guide the postoperative treatment.