I was always taught that it happens at approximately 3 weeks of age, although each week before that the ability develops a little more. Believe it or not, some vets don't know, and think a newborn pup's temp should be the same as an adult's. Adult human, maybe, adult dog, not yet!
As soon as the puppies are capable of purposeful movement (e.g., placing hind limbs, crawling toward or away from something), they are capable of raising or lowering their core body temperature. About 7-10 days.
they are at 96-97 degrees the 1st week, 97-98 week 2, 98-99 week3 and by 4 weeks at 100 degrees.
The intestinal tract stops working at about 94 degrees.
Heart rate 1st week about 200, repiration 15-35 per minute and kidneys are at 20% of adult rate so excess fluid comes through intestinal tract. High humidity, overeating and too much water when weaning can give watery stools.
Thank-You for the information below, it's been a weird start to summer here in the NE with varying outdoor temps. Our litter is 3 1/2 weeks old and I think the best indoor temp for both mom and pups has been around 72 degrees.
I have a litter that is the same age in the NE. I have been keeping the box at 70 this week, with a window fan across the room for circulation. We just put the long sides on the box so they will have more room to play and end to eliminate.
I was taught that pups control their own body temp. by 7 - 10 days old. I always give them 2 weeks to be sure. I have been operating with this understanding with no problems for years.
I am going to think about where I got that information though. I would like to hear scientific sources if anyone can provide that.
