How to keep him thin

Junior is my Whippet/Chihuahua cross, and when we adopted him, he was around 12 lbs, maybe a little under that. You could see his ribs, backbone and pelvis bones. We've had him for six weeks or so, and at the vet a couple days ago, he weighed in at 16.4 pounds. The vet said this is a very healthy weight for him.

He gets a two mile walk/run everyday, along with an hour of fetch. I was just wondering, how should I keep the weight off seeing that he gained four or five pounds with the routine we have? Thanks.

BTW, he is fed a cup of food twice a day. I know, that may be too much..

Would depend upon the type of food. Less calories in more food of a poor quality food.. better quality foods are more nutrient rich in a smaller amount of volume.

my JRTs.. who weigh from 12 pounds to 16 pounds eat any where from 1/3 of a cup to 1/2 a cup of food.. maybe slightly more when in training.

this is on high quality kibble. (Now they eat raw the whippets won't eat kibble so I don't know how much they would eat)

Well, you're feeding your whippet/chi the same amount of food I'm feeding my 55lb Aussie, just as a comparison.

It does depend a bit on the food but in general, that's far too much. What are you feeding?

I monitor the weight by adjusting the feed. IF i feel Mary is gaining..i cut it back a little then a little more consisantly until i get her where i think is best for her joints. IF I feel Victor is getting too thin i add. For him it must be something like nutrical because he is not going to eat more even if i beg him to. He just doesnt care about food that much. I did the same thing at the kennels. IT was hardest for some of the labs...every once in a while a female that has been fixed will just seem to adhere every bite directly to fat gain. Poor Maggie i tried everything ..upping her exercise profoundly..cutting her meals a bit more and more after that. I feel for people that have dogs like that.

I also give food by sight rather than a set amount.

If Bo is looking slim, I add an extra mugful here or there. If she's porking out I cut back.

I also often skip a feed, and usually only feed once a day.

But I am mean

firstly...
if the vet says hes a good weight now YAY!

but i would drop his food down (feed a high quality food and start by feeding a little less than the bag suggests for your dogs IDEAL weight...(not his current weight, not his "gotcha" weight but his ideal weight (about 16 lbs)
if on this amount of food he starts to loose weight, up his intake a little...if he gains weight take a little away.
keep an eye on his condition, you should be able to feel but not nessicarily SEE the ribs (they should have a nice think muscle cover on them) seeing the last couple of ribs is fine however, from above they should have a tuck to the waist and from the side a nice chest leading to a tucked tummy (depending on how hes built, chis can either be slim or cobby a cobby chi wil have a good barrel chest...and whippets of course should have a real nice tummy tuck going on.

make sure he gets plenty of excersize too...

My 25 lb super active dog gets 3/4 cup of food a day...so yeah, cut down on the food! Then you just play it by ear If she starts to look pudgy, we stop the treats for a while and up the exercise.

Post some pics of it. It will be great to see him.