In the first 10 days to 2 weeks after foaling, a mare will usually go into what is called a ‘foal heat’. This is her first heat cycle after giving birth. The hormones from the mare are passed on through the milk and the foal can get diarrah or what is commonly called ‘the scourers’. It is unsightly but usually not a health problem for the new foal. What worked for my babies was 1 or 2 doses of a probiotic. You can find this at your local feed or tack store, or go online and order from a horse supply catalog. The commercial name is Probias (that’s the brand I used). Probiotics are pretty safe and will reestablish the foal’s flora and fauna in his gut.