Mare's milk has a higher lactose than cow milk content. It has a similar amount to human breast milk. Still, keep in mind that the amount of milk used is very low and therefore the total amount of lactose ingested by taking the daily dose of mare's milk is also low.
The consumption of this raw milk may have beneficial effects for the lactose intolerant. Being raw and come from mares not altered microbiologically, this milk contains a proprietary bacterial flora that releases milk enzyme beta-galactosidase (lactase) that improves lactose digestion in our digestive tract. Furthermore, the presence of beta-galactosidase lactase stimulates residual remains in enterocytes (absorptive cells of the intestine) of the person, and improving enhancing action intolerance as this milk is consumed.