Swapping out breeder females?

[Lost571]

I have 16 - 1.3 and 6 - 1.4 colonies of rats to breed for feeders for our snakes.

I have been keeping a male with the girls at all times and have a steady supply of various sized feeders.

My questions are should I retire the whole colony at once and start fresh or could I replace 1 or 2 females and a couple of weeks or a month later could I replace the other females. I already replace males after 3-5 months of breeding. I currently have 5 males and 20 females being raised up for new breeders and want to know what you think is the best way to go about it.

Thanks for any thoughts , opinions , and experiences.

[cchardwick]

I was going to swap out my whole colony with new blood but decided to pair up a few new females and a few old females every week. Now I cull based on litter size and the apparent age of the rat, if I see a female that is older and has a small litter I'll mark it for culling. My new rats seem to have smaller litters to start, probably because they are still pretty young. Once they get bigger litter sizes I'll start culling the older female rats more often. The problem now is that I'm mixing up the new and old and it's hard to tell them apart, and I'm being over run with rats LOL. But with almost 50 snakes now I can feed multiple rats to each snake and use up 100-150 rats in a single evening.

I actually separate females from the males right before they give birth or shortly after if I miss pulling them. It gives the females a break after a litter is weaned before they give birth again and helps to control the amount of rats I'm producing. And after weaning I put them in a female only tub to give them another week or two off until I pair them up again. I usually pair up between 6 and 9 females per week, that's 60-90 babies per week with an average litter size of 10. The problem is if I get all large or small litters it complicates things a bit, I'd actually rather have too many rats than not enough. Not sure what I'm going to do this fall when I have 150+ hatchlings, I may have to make an order and do frozen thawed to supplement, or buy another rat rack LOL.

[Stewart_Reptiles]

If you replace all at once it could be weeks before your production gets going again.

I retire females that produce less then 10 animals and for every female retired two are held back, so I always have females of different ages with no disruption in production, same with male I retire 3 males at the time and do so in order and every 2 months.

[cchardwick]

My breeding was totally out of control up until about six months ago. I would get wild surges of tons of rats and then nothing at all. I finally got organized and started pairing up a certain number of females each week on a regular schedule, it gave me a consistent supply of offspring. Then pretty much all at once my whole colony grew old and production slowed way down. I had a surge of babies at the end and held back six tubs of six females to grow up. Then once I cycled through a few older females and my young females matured I started by putting a new male in the tub with six new mature females. I have two more tubs left, two weeks of putting new males with tubs of six new females. I didn't start until my females were mature so I didn't have a lag time. I like the idea of replacing females and males on a regular basis. It may be good to have a female grow out tub and every couple weeks add a couple weaned rats. Once Then pull out the mature ones as you go and add them to the rotation. I find keeping a rat colony is amazingly complicated and you have to be really organized.