Physical challenges for Labrador Retrievers running field trials are different than those for dogs engaged in sports such as Greyhound racing. In field trials, Labrador Retrievers frequently run in warm weather for 5 to 10 minutes over distances approaching a mile or more, with the additional mental task of locating the fallen birds.
In 1999, Matwichuk et al1 reported rectal temperature and hematologic, biochemical, and blood gas and acid-base values for 14 healthy Labrador Retrievers after they completed a 10-minute retrieving drill. Those investigators detected significantly increased rectal temperature, arterial blood pH, and PaO2 and significantly decreased PaCO2 and arterial blood bicarbonate concentration immediately after exercise. Subsequently, our laboratory reported values for healthy Labrador Retrievers during training and after completion of land retrieving tests at a field trial.2 The findings of that study confirmed that increases in rectal temperature and pHv and a decrease in venous PCO2 develop in association with this form of exercise.
In their report, Matwichuk et al1 stated that ambient temperature did not affect rectal temperature in dogs during the retrieving drill. Ambient temperatures in that study ranged from 11° to 28°C. In the other study,2 ambient temperatures were within a narrow range of 23° to 26°C. Again, no effect of ambient temperature on rectal temperature was apparent. The purpose of the study reported here was to assess physiologic effects of field trial exercise in dogs in a wider range of ambient temperatures. In particular, the intent was to determine whether dogs participating in field trials develop respiratory alkalosis and hypocapnia primarily in conditions of high ambient temperatures.
Venous blood pH
Eukanuba large-breed premium performance food, Iams Corp, Dayton, Ohio.
Monoject 1-mL tuberculin syringes (with detachable 25 × 5/8inch needle), Sherwood Medical, St Louis, Mo.
iStat portable blood analyzer, cartridges CG4+ and 6+, Heska Corp, Fort Collins, Colo.
Nikon Laser 800 rangefinder, Nikon Corp, Melville, NY.
Microsoft Office Excel 2003, Microsoft Corp, Redmond, Wash.
Statistical Analysis System, release version 9.1.3, SAS Institute Inc, Cary, NC.
Dr. Edward Aycock, past-president, National Retriever Club, Milwaukee, Wis: Personal communication, 2007.
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