age for breeding rats

[Nic]

How old do they have to be?
thanx,
nic

[mykee]

I'll be honest, I don't keep track of the ages of my to-be breeders, I focus on thier size. for me, I won't put a female rat into a breeding program until she is 250 grams, many will say lighter, but I have found that I have no stillborns, and produce consistent litters of 12-18. For males, they will breed much lighter, again, I wait until they are in and around 200 grams (which happens much sooner than with the females).

[Linds]

I'm with mykee on this one. My females produce the same litter sizes, as well as it would be impossible for me to keep track of all the females, but I would guess that I throw them in maybe around 2-3 months? Once or twice I have missexed a female and she's been in a bin with 20 boys... I'll be cleaning then all of a sudden I notice a rat with a belly :eek: These females have been bred as soon as they were fertile (possibly even sooner since males do breed earlier) and they all threw litters of 12-16 which is great for a first litter.

[Jayson]

I usually wait till 15-20 weeks of age for females. older females not only have larger litters but they also seem to last longer I have got females that are starting in there second year producing and still popping 12-16 babies a litter. Also keep in mind that females never bred can be too old to start ( I have heard from other breeders )
And i dont keep track of males
But i do find that young males are not near as productive as my year old males. Probably due to inexperience
Jason