The unexpected heat wave this summer has caused deterioration of mailed-in samples, especially those arriving over a weekend. The blood cells are destroyed and serum parameters may also be altered. Please add a cold pack with your samples. Be sure to wrap the tubes to avoid breakage in transit from movement of the cold pack. For mailed samples, submitting a blood slide along with the sample permits cell morphology to be evaluated in the event of sample deterioration.

Dogs
Our recent evaluation of dog urine cultures indicates that positive cultures become positive by 48 hours. Negative cultures at 48 hours remained negative at 72 hours. Thus, all negative canine urine cultures will be reported as final at 48 hours.

Cats
A few (~1%) of feline urine cultures become positive at 72 hours after being negative at 48 hours. Feline urine cultures will therefore continue to be checked for 72 hours.