Without an x-ray, it will be hard to tell. I noticed you said she had white spots "on" her body. If the spots you are refering to are on her body, that could be a possible reaction to the Oxcytocin. If you are refering to the spots visible through her abdomen I would lead more to binding, as they are quite large.
Given the situation that she is or has been breeding and age, would give way to that assumption/diagnosis.
The x-ray will, for the most part, tell all. This should have been the first step before treatment.
Starling is correct in that 1-2 injections may not be adequate and that it may not work at all. It is also safe to say that treatment will fail if the oviduct or vent is obstructed. Multiple eggs can and will form from either continued breeding or retained sperm.
Uriah is also not far off in the case of intestinal abceses, tumors, etc. I would think the the rapid onslaught of the objects would lead more toward binding however, two retained eggs can wreck an animal internally causing adjacent organs to become inflamed, irritated, etc. and to the naked eye, appear as additional retained eggs.
I know how frustrating it is and regardless of the vets perceived competency, explain to him/her what has been discussed via others here on this forum and use a little deductive reasoning and I'm sure you'll both reach an agreeable diagnosis. I will stress again...you will need an x-ray for a complete determination.
Keep a clear head and be respectful with the vet. He/She may be learning here also, so keep that in mind. Ask you vet if he/she has any collegues that might be able to consult. I can guarantee you that the vet is just as curious and determined to help your leo in the same manner you are.
Hang in there and don't get discouraged.
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Galen Clark
www.captivescience.com
