I am so sorry that your vet is making you feel this way. It is not right that he just refused you service because it was his afternoon off. He most certainly should have recommended taking your very sick dog to a specialty critical care/referral center for an internal medicine specialist to look at. It is interesting that your vet said that your dog's intestinal walls are thickened based on X-rays, as you cannot tell this from an X-ray. You would most certainly need an abdominal ultrasound to know that this was the case. I strongly recommend that you see a different veterinarian, preferable a specialist, if you want to have this problem resolved.
There are a number of different things that can cause chronic inability to gain weight in a dog. The most common of them is chronic endoparasitism. Endoparasites can include, hookworms, roundworms, tapeworms, whipworms, coccidia, giardia, etc... Therefore, I recommend that you submit a sample of your dog's stool for fecal analysis and a Giardia ELISA.
Other reasons that this could be happening include malabsorptive/maldigestive disorders such as exocrine pancreatic insufficiency, small intestinal bacterial overgrowth (SIBO), and certain forms of inflammatory bowel disease (IBD) like lymphangiectasia. The first step in diagnosing these disorders is to have blood and urine laboratory testing to look for changes that may be consistent with one or more of the things on this list.
Exocrine Pancreatic Insufficiency (EPI) is a disorder in which the pancreas is not appropriately producing the enzymes that are responsible for breaking down food into the molecules that can be digested by the intestine. These dogs keep eating, but do not gain weight because they cannot get the nutrients from the food. This can be diagnosed with a blood test called a TLI assay. If your dog has this disease, it is easily treated with an enzyme supplement called Viokase, which is put on the dogs food about 30 minutes before they eat it to predigest it.
SIBO is a condition in which there is an overgrowth of certain bacteria that normally live in the gut. This can result in chronic diarrhea, and altered malabsorption and maldigestion and gut motility. It is diagnosed with a serum blood test called folate and cobalamine. Treatment involves lifelong administration of metronidazole or Tylan powder to help control the overgrowth. Most dogs do well with gaining weight, once they are being appropriately treated.
Inflammatory bowel disease is diagnosed with biopsies of the inside of the intestinal tract, usually obtained using an endoscope. The treatment is specific to the type of IBD the dog has, but often involves a change to a special prescription diet and a low-dose of corticosteroids to control the inflammation.
I am attaching a client information handout that I use in my practice on weight loss. I hope that you find it useful.Click Here
Reddish/brown urine can be caused by blood or hemoglobin in the urine. Brown urine is usually caused by bilirubin in the urine (can be a sign of hemolytic anemia or of liver disease). This is a serious sign, and really needs to be dealt with as soon as possible.
If finances are of major concern, there are many organizations that exist to help with this. I am listing some of them here for you to contact and see how they might assist you.
American Animal Hospital Association _http://www.aahahelpingpets.org/home _" Through the AAHA Helping Pets Fund, veterinary care is possible for sick or injured pets even if they have been abandoned or if their owner is experiencing financial hardship."
__Angels 4 Animals _http://www.angels4animals.org/ _"Our services range from financial aid to complete treatment _to those pets and pet owners in need."
__Care Credit _http://www.carecredit.com/ _A credit card company for health care, including veterinary care. _"With a comprehensive range of plan options, for treatment or procedure fees from $1 to over $25,000, we offer a plan and a low monthly payment to fit comfortably into almost every budget."
__God's Creatures Ministry _http://www.all-creatures.org/gcm/help-cf.html "This fund helps pay for veterinarian bills for those who need help."
__Help-A-Pet _http://www.help-a-pet.org/home.html "Our efforts focus on serving the elderly, the disabled, and the working poor."
__IMOM _http://www.imom.org/ "We are dedicated to insure that no companion animal has to be euthanized simply because their caretaker is financially challenged."
__The Pet Fund _http://thepetfund.com/ "The Pet Fund is a registered 501(c)3 nonprofit association that provides financial assistance to owners of domestic animals who need urgent veterinary care."
I hope that this information is of help to you, and I wish you the best of luck with your dog. Please let me know if I can be of further assistance.