How many bales of hay does a cow eat?In: Cattle Feeding and Pasture Management [Edit categories]Answer:This depends on the size of the bale, whether it's a small square bale or a large round bale. A cow will eat 2.5% to 4% of her body weight per day. For a 1000 lb cow, that's 25 lbs to 40 lbs per day respectively, dry or lactating, respectively (lactating cows tend to eat 50% more than if they were dry). For a 1800 lb cow, that's 45 lbs dry to 72 lbs lactating per day, respectively.One small square bale of hay weighing around 75 lbs will feed one 1800 lb lactating cow per day, not counting wastage percentage. A dry 1800 lb cow will eat that bale up in around 1.8 days. That same small square bale will feed a dry 1000 lb cow around 3 days, and when she's lactating and suckling a calf, around 2 days.A large round bale of hay weighing 2200 lbs (one ton) will feed a lactating 1800 lb cow for 30 days. When she's dry, the bale will last her for less than 50 days. As for the 1000 lb lactating momma, that 2200 lb bale will last her for 55 days. When she's dry, she will be on it for 88 days.So translating that on a bale-per-day basis, here's the results, assuming no waste:1800 lb cow, lactating, fed small 75 lb square bale: 0.96 bales/day1800 lb cow, dry, fed small 75 lb square bale: 0.6 bales/day1000 lb cow, lactating, fed small 75 lb square bale: 0.5 bales/day1000 lb cow, dry, fed small 75 lb square bale: 0.333 bales/day1800 lb cow, lactating, fed large 2200 lb round bale: 0.033 bales/day1800 lb cow, dry, fed large 2200 lb round bale: 0.02 bales/day1000 lb cow, lactating, fed large 2200 lb round bale: 0.018 bales/day1000 lb cow, dry, fed large 2200 lb round bale: 0.011 bales/dayRead more: http://wiki.answers.com/Q/How_many_bales_of_hay_does_a_cow_eat#ixzz21DhSf2ta