Companion and Comparative Animal Nutrition Session
Regular exercise improves the health status of dogs; however, extreme exertion in the absence of adequate fluid and electrolyte replacement may decrease performance due to dehydration and cardiovascular stress. Unlike humans and horses, exercising dogs thermoregulate predominantly through respiratory and salivary losses, yet there is limited literature defining changes due to exercise in canine salivary electrolytes. The objective was to investigate the effects of a stepwise exercise regimen on salivary electrolyte concentrations in sled dogs. A training regimen was implemented whereby exercise intensity and duration increased incrementally over 12 weeks and was only altered due to inclement weather. Using sterile gauze and forceps, saliva samples were collected from 16 client owned Siberian Huskies at week-0 (pre-run, post-5.7km-run), week-6 (pre-run, 5.7km, post-39km-run), week-12 (pre-run, 5.7km, post-39km-run). Samples were analyzed for sodium, chloride, potassium, calcium, magnesium, and phosphorous using photometric and indirect ion-selective electrode analysis. Data were analyzed using PROC MIXED of SAS (v.9.4; SAS Institute Inc., Cary, NC). Means were separated using the Tukey adjustment. When compared across weeks, sodium, chloride, potassium, and calcium did not differ at any sampling time point. Throughout the 12 weeks, pre-run and 5.7km phosphorus, and 5.7 and 39km magnesium had increased (P< 0.05). Data were then pooled to evaluate changes due to run distance. Pre-run calcium and phosphorus was higher than at 5.7 and 39km (P< 0.05). Magnesium at 39km was greater than 5.7km, and at 5.7km was greater than pre-run (P< 0.05). Pre-run sodium was lower than at 5.7 and 39km (P< 0.05). Chloride at 5.7km was similar to pre-run and 39km, and at 39km was greater than pre-run (P< 0.05). These data suggest that as dogs become conditioned, they do not employ mechanisms to conserve salivary electrolytes, and that an electrolyte supplement with magnesium, sodium and chloride could be beneficial for sporting dogs.