Will my dog's underdeveloped kidneys grow to full size as she ages?

I wouldn't say that Angel's kidneys are negligible. They are still, though small than "average." This could be her normal (not all dogs will have organs of the average size, since a 10 pound dog will have smaller kidneys than a 100 pound dog). Other causes for small kidneys could be a congenital disorder, fibrosing or scarring of the kidneys, significant dehydration, among a few other things. Ultrasound still images can be very hard to interpret since you need to scan through things to be able to get the whole picture. From the still images, either they do not capture the actual kidney, or there is so much damage that they are not a normal appearance anymore. Even though this link ( http://www.ultrasoundpaedia.com/normal-kidney/ ) is for humans, dog kidney images will look very similar. You can see a few different shapes, and the odd shapes seen in the pictures in the link are not seen on your images. Causes for loss of architecture (kidneys that are more or less mushed all together) can include infection, scarring, cancer, etc. Even though she is young, it is possible for Angel to be in kidney failure. Bloodwork and urinalysis would be the tests to show this. If she is in failure, then she would need dialysis to continue with life.

I think the best prevention is routine monitoring of bloodwork and urine. Kidney values can be trended yearly. If they start to become abnormal, your vet can recommend diet change and supplementation as needed. If your dog is not sick, bloodwork may not be covered unless you have wellness coverage.

Based on the mix of breeds you said I would suspect that Gracie has done the majority of her growth already. You might see some very small amounts of growth until 18 months of age but for the most part she will hopefully remain that size forever.

Even though Orux is smaller than his siblings, he can still grow to close to full size. He may be a bit smaller than them when he becomes an adult, but he should be around their size. Keep in mind that every breed has a range of sizes and weights, and dogs within that breed can go anywhere on the range. So even if he's on the smaller size, he will still be within the normal range for a Rottweiler. Only time will tell how big he will become. I hope this helps.

Hello, sorry to hear about Canela. It’s likely that your medical management of her is supporting her kidneys really well. However, kidney disease is considered a progressive disease, meaning it only gets worse. Despite this, progression may be very slow and thus patients may live a long life with medical management. Keep up the good work, Canela is very lucky to have you , Best of luck

In many cases of acute kidney injury, recovery is possible but not guaranteed. Intensive treatment is required to support her until her kidneys have a chance to recover and regular monitoring would be recommended to track any ongoing effects if she does recover

Hi and thank you for your question on Petco Pet Education Center, formerly Petcoach! It could be her genetics if her mother or father were not as tall or the height issue could be related to a dysfunction of the pituitary gland which controls growth. A blood test at your veterinarian's office can determine if the reason behind the short stature is pituitary related. I hope this helps!