Hello, my name is Dr. Farwell. I can try to help answer your question about your pup
Sorry to hear about the little one. But good that the others are well
Can you open her mouth and check the roof of her mouth - here we are checking to make sure it's solid. If there is a split down the center, she may have a cleft palate which would be a possible cause for her doing poorly
There are many other congenital abnormalities that are possible here - heart conditions being one. This would have to be determined by an examination with your regular vet. We can often pick up on congenital murmurs early because they are very loud.
Unfortunately many of these scenarios, occurring at such a young age would likely result in her eventually passing away
No, their is no split down the centre
Good. Will she suckle from a bottle if you try to supplement her?
Sometimes additional supplementation is necessary, especially if mom has many other pups.
You could try going to your local pet supply store and picking up some puppy milk replacer and a bottle. If she is really very weak, this might be her only chance at making it.
Small breed pups can become hypoglycemic ( low blood sugar) quickly if they haven't eaten for a several days
How many pups are in the litter?
5 pups in the litter
Cairn Terriers are also predisposed to congenital liver shunts. This is an abnormal blood vessel that shunts blood around the liver. These pups often fail to gain weight, and are poor doers. It can affect them very young, or after they are several months old. However these individuals are often called the "runts" of the litter
My recommendation for now would be to keep her warm. If you have any puppy milk on hand, try to get some down her. You can also give a small amount of Karo syrup on her tongue if she will take it.
1st thing in the morning I would take her to your regular veterinarian for examination. However, if she is really doing very poorly, you may want to consider an emergency facility if you have one in your area.
Small pups can pass away within 12 hours of dehydration and low blood sugar.
The emergency clinic may have puppy milk and bottles on hand for you .... since pet shops wouldn't be open. Sorry for not registering on that comment earlier, we must be in a diff time zone.