How many 4x5 bales of hay is needed to feed 100 cows for 180 days?

Answer 1

Weight of the bales will help here. When we have the weight of each 4x5 bale, then we can properly calculate an estimate of how much is needed to feed 100 cows for 180 days.

Remember that one cow will eat at least 2.5% of her body weight, often more during cold periods and when she's nursing a calf (which can be upwards to around 4% of her body weight). Assuming that your cows are all around 1000 lbs (which they probably aren't), then, all together, they will be eating around 2500 to 4000 lbs of hay per day. Let's go the safer route of over-estimating the amount they eat and say that they eat 4000 lbs per day. To calculate, 4000 lbs/day x 180 days = 720,000 lbs or more of hay is needed during that time period.

Now, as for the weight of the bales, we can only assume here. So let's say that a good compacted 4' x 5' large round bale of hay weighs around 1200 lbs. So going with our estimate of needing to have 720,000 lbs of hay over 180 days for 100 cows, that means you will need 720,000 lbs / 1200 lbs per bale = 600 bales.

I would definitely not get 600 bales, as there is a risk that you may run short. It's better to have too much hay than too little. And also know the average weight of your cowherd so you can make a PROPER estimate over 180 days of how much hay you ACTUALLY need. You may have an average herd size of 1400 lbs; you may have a herd that is mixed of different ages and sizes of cattle, which also need to be taken into account. So please, know the weights of each 4' x 5' bale, AND the average weight of your cowherd.

Just for kicks, lets see the difference in number of bales for 100 x 1000 lb cows to the number of bales for 100 x 1400 lb cows.

1400 lb x 0.04 = 56 lb/day

56 lb/day/cow x 100 cows = 5600 lbs/day

5600 lbs/day x 180 days = 1,008,000 lbs of hay

1,008,000 lbs x 1200 lbs/bale = 840 bales

So you see the differences? Pretty remarkable, eh? So once you know how to calculate everything out, then you will know how many bales to get. Don't be afraid to over do it, like in this second example, you may want to get 850 or even 875 bales instead of 840. And in the first example, you may want to get 650 bales instead of 600.