I'm just curious to how much weight does a bass put on during the spawn.  I guess an example is take a bass that weighs 5 pounds before the spawn and take the same bass during the spawn does it like gain a pound because of the spawn or do they gain just ounces.  

Bass will lose weight during the spawn. They are not completely consumed with the rigors of reproduction.  Feeding is secondary to breeding.

Avid, I think he's asking how much weight will eggs add to a female, before she spawns.  (as compared to like the summertime weight.  

I'm sure it varies from fish to fish, but I'd suggest it's in the neighborhood of 20%.  A 5lb fish could go 6lbs and a 10lb fish could then be 12lbs.  Like I said it will likely vary from fish to fish but I'd bet that 20% is within 5% either way, on average.

Here is a fish that Clipper caught a couple of years ago. She had just finished spawning. How much do you think she weighed?

only 5lb 2oz

Female bass keep gaining since they only loose a day spawning. When they drop the eggs that's a weight loss. But they keep feeding all along while Mr. Bass loses at least a month (two in the deep south) of adequate feeding while guarding one or more beds one at a time. In some lakes up to 25% of males die that summer, some lingering on until hard winter. The males grow roughly half the female rate because of the spawn rigors, so nationwide don't grow much longer than 16 inches, even among the Florida strain.

Jim

I couldn't tell you from my own experience, but from what I've read

it can vary considerably but ballparks around 15%.

For example, a 7-lb cow may weigh 8-lbs when ripe with roe.

After finished spawning however, she'll weigh less than she weighed before she was ripe.

Roger