Breeding size

What is the average weight for sexually mature female rats? I had 1.3 rats that I got from someone and they have been together for about 3 months now and no babies have occurred. The male rat is over 400 grams and the females are about 225-250 grams. I've tried putting them all together in one bin and I've also tried rotating them through the male.

My girls are bout 200 when I put them with one of my males. All my males are over a pound an a half. Just give it little more time

Sexually mature and optimum weight are really 2 different things.

Rats become sexually mature at 5/6 weeks of age however weight wise ideally you want to wait till the females are about 200/250 grams.

Did you get that group at that size? If you did it is possible that your group is already too old, either the male, the females or both which is why I always encourage people to get small rats around 4 to 5 weeks and raise them up to size.

It really depends. When I grow up my females I will put a male in with them around 200 grams. I leave the male with them for five days, or one heat cycle.
There are a lot of factors though, temp, food, security, etc. If all those factors seem good, just give them a little time and I am sure you will see the females start to get fat :gj:

Quote:

---

Originally Posted by Deborah

Sexually mature and optimum weight are really 2 different things.

Rats become sexually mature at 5/6 weeks of age however weight wise ideally you want to wait till the females are about 200/250 grams.

Did you get that group at that size? If you did it is possible that your group is already too old, either the male, the females or both which is why I always encourage people to get small rats around 4 to 5 weeks and raise them up to size.

---

No I have raised them up from weans. I had another male that stayed with the current male while they were growing up so they stayed separated from the females but he got out as I was cleaning and the cat got him :( they're being fed the mazuri breeding diet.

Quote:

---

Originally Posted by mattj8501

No I have raised them up from weans. I had another male that stayed with the current male while they were growing up so they stayed separated from the females but he got out as I was cleaning and the cat got him :( they're being fed the mazuri breeding diet.

---

How big were the females 3 months ago when you started your pairings?

If they were way smaller and just are now getting up to optimum size I would give them another month, if then you still have no result I would replace the male.

Quote:

---

Originally Posted by Deborah

How big were the females 3 months ago when you started your pairings?

If they were way smaller and just are now getting up to optimum size I would give them another month, if then you still have no result I would replace the male.

---

They were about the same size. It's like they hit a growth "wall". But they were anywhere between 175-225 grams.

Quote:

---

Originally Posted by mattj8501

They were about the same size. It's like they hit a growth "wall". But they were anywhere between 175-225 grams.

---

Since it's not likely that you have 3 females with issues (unless you really have bad luck), I would just go ahead and get a new male, he is either a very shy male or he could be sterile.

Quote:

---

Originally Posted by Deborah

Since it's not likely that you have 3 females with issues (unless you really have bad luck), I would just go ahead and get a new male, he is either a very shy male or he could be sterile.

---

I agree, three females with problems seems very unlikely, I would try another male and see what happens.

i dont breed my females til they're about 5-6 months old & around 250+ g if possible too.
i also stop breeding when they reach 1 1/2 yrs.
from what i've read theres nothing to support the idea that old rats cant produce...they can just their success rates are lower.
Temperature is also a big factor too.
I've found that if its hot the rats wont breed & i run into this issue in the summertime months. Once i started keeping the room cooler, i started getting better success with them &
lastly what they're fed is a big key factor in their overall health.
i switched off of lab block food & now i feed a 50/50 mix of a store bought food as well as my own homemade mix that i put together for them that includes cereals, rolled oats, dried fruits & veggies & sometimes sunflower kernels. i dont feed the junk treats that the stores sell. thats all unhealthy crap. period.
My rats treats are either fresh or home dried fruits like apple slices. My seniors get 1 dried prune every week just to keep their digestive systems running smoothly.
Anyhow, After switching to this food mix i found the rats had better energy levels & their fur is shinier & softer & they're just healthier looking overall.
Healthier adults produce healthy babies that become more nutritious feeders :D.