While not exactly a major sign of food allergies, the number of times a day a patient passes stools can raise suspicion of the condition.
Between 60% and 65% of dogs with adverse food reactions (AFR) have concurrent gastrointestinal disturbance (Paterson, 1995) and (Loeffler, 2004).
Another study confirmed my impression dogs with AFR produce on average 3 stools a day, compared with an average of 2.1 stools/day in atopic dogs and 1.6/day in normal dogs (Loeffler, 2004). This decreases to normal in dogs with confirmed AFR once managed.
So, it’s definitely worth asking the question, and given encouraging clients to undertake food trials can be challenging, this can be very helpful in discussions as to the possible causes of pruritus.
Paterson S (1995). Food hypersensitivity in 20 dogs with skin and gastrointestinal signs, Journal of Small Animal Practice 36(12): 529-534.
Loeffler A et al (2004). Dietary trials with a commercial chicken hydrolysate diet in 63 pruritic dogs, Vet Rec 154(17): 519-522.