# Two Litters less than 2 days apart at VASTLY different sizes?



## wug (Oct 3, 2015)

Just a little background first. I have two girls that gave birth less than 48 hrs apart on OCT 1st and 3rd. The first litter had 12 pups, the second litter 15. 2 passed away from the 12 lot and 1 from the 15 lot. I put one pup from the remaining 14 litter into the remaining 10 litter for 11 total to even it out and make a bit less work for the one mom. 1 more passed away from the 11 lot so the two girls have been feeding 10 pups (Born Oct 1) and 13 pups (born Oct 3rd) respectively. The pups appear to be fine and have none have passed since the last one 6 days ago but my question is why is the smaller lot of 10 growing exponentially faster than the 2nd lot of 13 at what seems to be twice the rate. Most of the pups are easily twice the size of the lot born Oct 3rd and of course more active. 


I realize they grow fast and expected a slight size difference but even the one I took from the later litter of 15 is virtually the same size as its "new" litterates in the smaller lot I put it with and is approaching twice the size of its sisters and brothers. 3 days ago when I checked the first lot of 10 after having not checked them for almost 2 days I was litteraly shocked at how large they were compared to the other lot.


The mothers seem to be spending the same amount of time feeding so this seems strange to me


----------



## wug (Oct 3, 2015)

Editing messages for 10 min a little extreme, here are the photos I was trying to find to post in the original comment

1st litter Born Oct 1st (Much larger than 2nd lot). Maybe a bit hard to notice in photos but I would say they are almost twice as large especially in "body mass", not so much in overall length









2nd Litter Born 36 hrs later


----------



## moonkissed (Dec 26, 2011)

Well babies grow crazy fast. A few days difference can actually be a bit of a difference. I was just talking in a group about how my little runt had a huge growth spurt and she grew so much like overnight lol Babies go from naked blind/deaf little pinkies to rats in like 8 weeks. Literally overnight they change so much!

But at the same time alot goes into good growing babies. Healthier moms, different ages of moms, the smaller litter even though not by many babies less, still means they are going to get more milk from mom as they have less babies to compete with. 

it is nothing to worry about, they will likely all catch up fine. I assume you are feeding both moms the same, but you could give the mom with more babies alittle extra protein to help her out.


----------



## wug (Oct 3, 2015)

moonkissed said:


> Well babies grow crazy fast. A few days difference can actually be a bit of a difference. I was just talking in a group about how my little runt had a huge growth spurt and she grew so much like overnight lol Babies go from naked blind/deaf little pinkies to rats in like 8 weeks. Literally overnight they change so much!
> 
> But at the same time alot goes into good growing babies. Healthier moms, different ages of moms, the smaller litter even though not by many babies less, still means they are going to get more milk from mom as they have less babies to compete with.
> 
> it is nothing to worry about, they will likely all catch up fine. I assume you are feeding both moms the same, but you could give the mom with more babies alittle extra protein to help her out.



Yes but remember the are approx 36 hrs apart so not days. I understand there is more milk for the smaller lot tat makes sense, and I could understand if just a few were smaller but the entire lot is well behind. I imagine they will catch up though as you say. I have been feeding both moms the same food and lots of protein. I think the one with smaller litter eats a bit more though. thx for the reply.


----------



## Isamurat (Jul 27, 2012)

There can be a fair few factors that effect this. 

The first is genetics, some rats genetically grow faster than others, this tends to go in family lines. I've had litters who have been a good 150% the weight of other litters at the same age, some of that is number of babies, but not all.

The second is down to mum and her ability and interest in feeding. Some rats are very attentive mothers, they barely spend any time off the nest and seem to live to feed there babies. Others do what they need to do but are more interested in other things such as eating or begging to come out. Neither is neccesarily wrong as long as the kittens are getting enough food to grow healthily and both sets of babies look fine to me. 

Then you get the affect of the 36 hours, it doesnt seem long but looking at the weights of some of my past litters i typically see babies doubling in weight from 2 days to 1 week, then doubling again every week until 4 weeks when the rapid growth slows down a bit. 

Finally theres smaller factors such as the richness and quantity of the mothers milk (often linked with how much she's choosing to eat) the amount the babies suckle and even how many nipples mum has. The food mum ate whilst pregnant can also make a difference, a mum who ate lots of high quality food is likley to have bigger babies than one who ate less or lower quality.


----------



## wug (Oct 3, 2015)

Isamurat said:


> There can be a fair few factors that effect this.
> 
> The first is genetics, some rats genetically grow faster than others, this tends to go in family lines. I've had litters who have been a good 150% the weight of other litters at the same age, some of that is number of babies, but not all.
> 
> ...



Thanks for the insight in your reply. certainly makes sense, I know a few things for certain. 1) in the time I have had them (over a month) they have both eaten virtually identical portions of the same food. 2)They are sisters from the same litter, 3) they both seem to spend equal amounts of time feeding (quite a bit) and take very similar "break" lengths as well. In fact if I had to say one "fools around" more and spends more time AWAY from her babies its the one that gave birth first with the much larger pups. Go figure lol 

THANKS again


----------



## Mojojuju (Nov 15, 2014)

Always the possibility, too, that some of the babies are dwarfs? I dunno.


----------

