If Tasha is not spayed, then I am concerned that she could have a pyometra (a uterine infection), this is diagnosed with radiographs (x-rays) and blood work. The treatment is usually an emergency surgery to spay her.
If she is spayed, blood work and radiographs would still be recommended to determine why she is lethargic and has a bloated abdomen.
Some of the things that can be causing lethargy, gagging, labored breath, and bloating include:
2. Heart failure
3. Adrenal gland disease (Cushing's disease or Addison's disease)
4. Foreign bodies (having eaten something that she shouldn't have eaten)
In all of these situations, the progression of her signs indicates that she needs to be seen by a veterinarian again, but have diagnostic tests run. as well.
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