Experienced and professional animal trainer provide their insights in answering this question :
A. Osteoscarcoma can be very painful so as it grows he will start to have trouble eating, will get increased pain and become increasingly depressed. He may even become short tempered and aggressive due to feeling uncomfortable and painful.

How to Identify Common Pet Problems ?

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The final stages of osteosarcoma can cause significant illness in dogs when the lungs are affected by metastasis, causing respiratory distress and pain. Euthanasia is often the most humane option when dogs are having more bad days than good.
Osteosarcoma is unfortunately a fast-spreading tumor. By the time the tumor is found in the limb, it is considered to have already spread. Osteosarcoma spreads to the lung in a malignant process called metastasis.
Osteosarcoma of the limb bones can be extremely painful and the typical presenting complaint for these dogs is that of an intermittent lameness. The lameness may respond to standard doses of pain-killers initially but rarely for more than a week or so.
In this calculation, the median survival for osteosarcoma of the mandible was associated with longer survival (OS, 10.4 years) than in cases with osteosarcoma of the skull/facial bones, including the maxilla (OS, 6.3 years; and DSS, 18.8 years).
Around 50% of diagnosed dogs will survive for a year if treated. For osteosarcomas, estimates depend on where the tumor is located. If the tumor is in the mandible or scapula — the jaw or shoulder blade — average survival is around 18 months. If it`s in a limb, the average survival is 11 months.
Without treatment, life expectancy for dogs with osteosarcoma of the leg is usually less than 4 months. With aggressive therapy, dogs have a 50% chance of living 1 year or longer.
If your dog`s activity is limited due to bone cancer, make sure you spend a good amount of time by their side, comforting and cuddling them. Your dog can`t chase you to be close to their favorite person so you need to go to them. Cuddle often and for long periods of time.
(Bone cancer rarely produces complications that cause a pet to pass away without being euthanized.) Sometimes it is obvious that it is the right time for euthanasia: the pet`s pain may become unmanageable, or the pet might stop eating.
It is important to understand that if an amputation is performed for osteosarcoma without chemotherapy, most patients develop metastatic disease and succumb to the cancer within 4-6 months, which is why we don`t always recommend amputation as a sole therapy.
The cause of this cancer is unknown but based upon common breeds, there appears to be a genetic component. Other proposed causes include microscopic injury to bones in young growing dogs, metallic implants, and trauma.
Clinical symptoms include pain, swelling, loose teeth, separation of teeth, and paresthesia [10]. Radiographically, osteosarcoma can appear with a variable bone density depending on the amount of bone formed by the neoplasm.
Jaw osteosarcoma treatment

Because the jawbone is considerably more delicate and complex than longer bones in the body, jaw osteosarcoma surgery can be particularly challenging. Treatment for osteosarcoma of the jaw may also involve chemotherapy and/or radiation therapy.

Osteosarcoma accounts for approximately 85% of bone tumors in dogs. The median age at diagnosis is ~8 years, with a small peak of incidence in young animals (younger than 3 years).
Osteosarcoma, a cancerous bone tumour, was found to be much more common in giant dogs, including the Scottish Deerhound (3.28% of all dogs affected each year), Leonberger (1.48%), Great Dane (0.87%) and Rottweiler (0.84%).
With OSA, a cure is possible, but in dogs actually occurs less than 20% of the time. Prolonged remissions of 1-2+ years are not uncommon.
Golden Retrievers have a high chance of getting cancer. About 60% of golden retrievers die because of cancer. In the 1970`s, their lifespan was between 16 and 17 years old, and now they live until 9 or 10 years old. We recommend taking your Golden to the vet at least twice a year to make sure everything is ok.
The most common way to evaluate for metastasis involves taking three-view chest X-rays to look at the lungs. If the vet sees nodules in the lungs, this means the osteosarcoma has metastasized.
Foods of interest in dogs with cancer include high quality protein such as dairy products made from goat or sheep, egg, low-mercury fish, organ and muscle meat preferable natural raised. Healthy, low glycemic (GI) carbohydrates such as sweet potato, broccoli, quinoa and gluten free oats.
Osteosarcoma is not a curable cancer, however it is treatable. Local disease control in combination with systemic chemotherapy can give your pet many months to years of good quality life.
Osteosarcomas are malignant neoplasms of the bone which commonly affect the long bones. The involvement of the jaws are rarely noticed. These neoplasms often shows a typical clinical behaviour as well as varied radiological appearances. Similarly, their histological growth pattern can be quite diverse.
Osteosarcoma is the most common type of cancer that begins in you or your teenager`s bones, usually in the arms or legs. Limited movement, bone pain, a lump and an unexplained broken bone are the most common symptoms.
Today, about 3 out of 4 people who have osteosarcoma can be cured if the cancer hasn`t spread to other parts of the body. Almost everyone who is treated with limb-sparing surgery ends up with that arm or leg working well. Many people who have osteosarcoma will need physical therapy for several months after surgery.
In most primary bone sarcomas, there are 5 stages: stage 0 (zero) and stages I through IV (1 through 4). The stage provides a common way of describing the cancer, so doctors can work together to plan the best treatments.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. My 9yr old Golden Retriever was diagnosed with Osteosercoma in his mouth. What can I expect? What will happen to him as it gets worse?
ANSWER : A. Osteoscarcoma can be very painful so as it grows he will start to have trouble eating, will get increased pain and become increasingly depressed. He may even become short tempered and aggressive due to feeling uncomfortable and painful.

ANSWER : A. Somewhere along the line she has learned that this gets her something she wants, attention, food, something, and now we have to teach her that behaving and being quiet gets her what she wants. Don’t reward her whining and bouncing by giving her attention. Instead, ignore her, going about your business until she quiets and settles down. THEN give her a treat, petting, and praise. She needs to learn that being the well-behaved dog is what will get her the attention she craves. Teaching her obedience will help her learn how to behave in various situations and to look to you for how to behave. And, above all, make sure your dog is getting sufficient physical and mental exercise every day. A tired dog is a good, happy dog and one who is less likely to bark and misbehave from boredom or frustration. Depending on breed, age, and health, your dog may require several long walks as well as a good game of chasing the ball and playing with some interactive toys. Kong toys filled with peanut butter are an excellent way to reward her for being quiet and keep her that way for a good while as she plays with her toy and gets the peanut butter out.

Q. My cat is dripping saliva from his mouth and Its gooey it also smells..what does it mean?? And what can I do??
ANSWER : A. Drooling can indicate getting something that tasted bad, nausea, tumor of the mouth, throat or esophagus, mouth pain or something caught in the mouth. I recommend getting him in to see your vet as soon as possible for an oral exam and possibly x-rays to determine the cause for his symptoms and get him started on treatment.

Q. We have a 3 yr old Weiner dog, she is having pus in her eyes, I took her to the vet he gave me derma vet ointment, used it as the doctor prescribed
ANSWER : A. If the pus really isn’t all that bad, and it’s just some discharge, your pup may benefit from a diet change. It could be that the food you’re feeding just isn’t right for your dog, and that’s okay! Dogs grow and change over time, and now that your dog is fully matured, a diet change may be in order. Try something like Taste of the Wild, maybe a grain free dog food, Orijen, or Ziwipeak. These are all really great food options.

If the pus is really bad, and continues to get worse, see your vet again and let them know what’s going on. Maybe you could try a diet change, and then see if there are any improvements.

Remember, you should always gradually change a dogs diet. By gradually, I mean you put a tiny bit of new kibble in with a bowl of the old kibble. Reduce the old kibble by just a few bits of kibble. Throughout the course of at least two weeks (or as long as you want depending on whether or not you want to finish off the old food) you slowly add more of the new kibble while removing some of the old kibble. This makes the process gradual, and won’t cause any tummy-upset in your dog.

Q. My cocker spaniel is 9 years old. He has involuntary bowel movements (little drops) very frequently, especially when he is asleep.
ANSWER : A. Is your dog on a senior dog food? I would get your dog on a high quality high protien dog food. Ask a pet store assosicate or your regular vet for a food recommendation. When you buy a better food the dog will have to eat less to get the same amount of energy from the food. The dog has to eat more of the cheaper foods to get the energy it needs from it. Meaning more poop and buying more food. So the cost really evens out. So the lessen your dogs bowel movements get on a better senior dog food. Next talk to your vet they may have a recommendation. If you switch dogs do it slowly by mixing the foods. Start with 10% new 90% old mixed for at least a week until you have switched to 100% new 0% old. Senior foods have more fiber to help with bowel movements. Take the dog outside to go potty more frequently, right before bed time.

Read Full Q/A … : Symptoms Questions & Answers

Q. My 13 year old male cat is acting lethargic & doesn’t seem to be feeling well. I don’t know what’s wrong except that he has fleas. Can too many fleas
ANSWER : A. Excessive fleas can cause anemia in cats, left untreated, this can be life-threatening. I recommend getting your cat seen by your vet right away for his illness. For every flea you see on your pet, there are 100 more in the environment. Get your pet on a good topical or oral flea control through your vet. In flea control, you get what you pay for. Consider asking your vet for a dose of Capstar. It helps get the problem under control by killing the fleas on the pet starting in five minutes but only lasts for 24 hours.

You need to treat your home. If you use a pest control service, tell them you are having a flea problem and they can adjust their treatment. Use a premise spray that also contains an IGR, insect growth regulator. This keeps eggs and larvae from maturing into adults and helps break the life cycle. Also, vacuum EVERY DAY, throwing out the bag or emptying the canister every time into an outside receptacle and spraying the contents with insecticide to kill the fleas you’ve vacuumed up.

Treat your yard, since fleas will hop a ride into your home on your pant leg without you knowing it. Concentrate on areas under bushes, in the shade. Fleas are less likely to be located in open sunny areas where it gets hot.

If chemicals are a problem, you can use borax. Sprinkle it into rugs, into corners and under furniture, use a broom to work it into the fibers and let it sit for hours, days even. It won’t hurt you or your pet. Then vacuum it up, reapply as needed. Food grade diatomaceous earth can be gotten from a health food store and worked into the rugs and corners in the same way. These treatments aren’t as fast and effective as chemical insecticides but they can help.

Be patient, you may have to repeat these steps multiple times 10-14 days apart to help break the flea life cycle.

Q. My dog is 12years old and is getting what look like moles on several parts of her body. Should I be concerned or is this old age?
ANSWER : A. Dogs do get more skin growths as they age, some breeds more than others. Unfortunately no one can tell you just by looking whether these growths are benign or cancerous – typically we need to do a needle or full biopsy to know for sure. Sometimes we can recognize typically benign growths, but again, you’ll need to consult with your vet to get these checked out and get his opinion. I always think it’s a good idea to have a “tumor map” in older dogs, to note the location and size of growths so that they can be easily monitored.

Q. Cat had major problems getting a hairball up 2 days ago had to pull it out her mouth for her. Now when she eats she vomits all food up immediately
ANSWER : A. I’m concerned that bringing up the hairball and the subsequent pulling may have caused your cat to have some esophagitis. This needs treatment with products like sucralfate to soothe the esophagus and help it heal. She needs to see a vet ASAP in order to get some treatment that will help her; otherwise she’ll likely continue to vomit and get progressively worse.

Keep in mind as well that the vomiting you’re seeing now might not be related to the hairball incident, so she may need labwork and x-rays to diagnose what’s going on.