Experienced and professional animal trainer provide their insights in answering this question :
A. It is likely the tumor has become infected or ruptured. Please get him investigated and treated as soon as possible as this could become both very painful and life-threatening

How to Identify Common Pet Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced pet care professionals :

Prognosis for spinal cord tumors in dogs

The majority of patients have a survival rate of less than 6 months. As a pet parent, it`s important to consider your dog`s well-being and comfort at this time.

Mast cell tumors: End stages of aggressive forms of mast cell tumors often affect body organs such as the liver and spleen, leading to lethargy, vomiting, diarrhea, weight loss, no appetite, and sometimes, anaphylactic reactions.
Skin squamous cell carcinoma is the most commonly diagnosed form of skin cancer in dogs. These tumors appear as raised wart-like patches or lumps that are firm to the touch and are most often found on the dog`s head, lower legs, rear, and abdomen.
Key Takeaway: A small bump on your dog`s back might be caused by an a bug bite, a blister, a cyst, a pimple, a tick, or a tumor. An itchy bump might be caused by an abrasion, bug bites, hot spots, scabs, ticks, or pruritus. A large bump might be an abscess, a sebaceous cyst, a lipoma, or a mast cell tumor.
Tumor growth of the spinal cord can be either benign or malignant; however, even a benign tumor can cause spinal dysfunction. The symptoms often present slowly and without pain initially.
A spinal tumor can be life-threatening and cause permanent disability. Treatment for a spinal tumor may include surgery, radiation therapy, chemotherapy or other medications.
High Grade Mast Cell Tumors

These tumors share a universally bad prognosis with survival times of less than 4 months. They behave aggressively and require more aggressive therapy.

Mast cell tumor (MCT), also called mastocytoma, is a common skin tumor in dogs. The mast cell tumor is the most frequently diagnosed malignant skin cancer in dogs. Dogs are diagnosed at an average of 8 years old, although puppies as young as 4 months may be affected.
For most dogs, mast cell tumors are not a painful cancer. In fact, mast cell tumors are typically diagnosed after a pet owner takes their dog to the veterinarian because they`ve felt a lump in or under the skin. If other organs are also affected, you may see these signs: Decreased appetite.
Cancerous or malignant tumors can be hard or soft. The feel of a mass and whether it bothers your dog has little to do with whether it is cancerous or not.
One may feel firm, raised wart-like blemishes that are squamous cell carcinoma. One may see rubber-like, inflamed sores that are mast cell tumors. Melanomas can look like strange-colored lumps or bumps on the lips, mouth, pads of feet, or toenail beds. Dog owners may see other pain symptoms, such as limps.
In other cases, the epitheliomas may appear solely as cornified cysts. They most likely arise from a hair follicle. These tumors can develop anywhere on the body, but they occur most frequently on the back, tail, and legs. Middle-aged dogs are most at risk.
Surgery for a spinal tumor can be complicated based on the tumor location. If the tumor can be fully removed without impacting the functionality of the spinal cord, surgery is a good treatment option. Chemotherapy is used to treat spinal tumors that have already spread or have a high risk for spread.
Extradural (1), intradural-extramedullary (2), and intradural-intramedullary localization of a spinal cord neoplasia. Extradural tumors are the most prevalent type in dogs, accounting for 50% of the cases.
Primary tumors often progress slowly over weeks to years. Tumors in the spinal cord usually cause symptoms, sometimes over large portions of the body. Tumors outside the spinal cord may grow for a long time before causing nerve damage.
Sharp or shock-like pain.

Pain from a spinal tumor may be limited to a specific region in the back, or it could travel along a nerve root (radicular pain) or the spinal cord (myelopathic pain).

The last few days before your dog passes you may notice: extreme weight loss, a distant look in their eyes, a lack of interest in anything, restlessness or unusual stillness, a change in the way that your dog smells, and a changed temperament.
Fibrosarcomas are common, fast-growing malignant tumors in dogs. Most are on the trunk and legs and vary in appearance and size. Those under the skin`s surface appear lumpy, while those deep under the skin may be firm and fleshy. They can invade underlying muscles, but most do not spread to other areas of the body.
Most dogs with low-grade mast cell tumors are able to live to their normal life expectancy once the tumor is gone. Dogs with high-grade tumors have a much higher risk of the tumor spreading to other organs in the body, which makes the cancer more difficult to treat.
Some mast cell tumors grow slowly over time, while others seem to pop up overnight and grow rapidly. They can also wax and wane, swelling when the mast cells degranulate. Handling the tumor can cause degranulation, causing the tumor and surrounding areas to feel itchy as well as to grow larger.
In rare cases, mast cell tumors may disseminate, spreading rapidly and growing throughout the body. The most common locations for spread include the dog`s lymph nodes, liver, and spleen.
Mast cell tumors in dogs have different “grades”, or levels of severity, and the life expectancy can vary from as little as a few months (with an average of 4 to 6 months) in a Grade III tumor, to years with a Grade I tumor.
Answer: Mast cell tumors (MCT) are the most common malignant tumor in dogs. Thankfully, most MCTs (more than 80 percent) are of low or intermediate grade and curable with surgery alone. So, you are correct that surgical removal is the treatment of choice in most cases.
Grade of tumor – Grade III is the worst with the shortest median survival time – reported median survival time is 3.6 months, Grade II disease often carries a median survival time of up to 2 years.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. How can I train my 4 month old puppy to sit?
ANSWER : A. Training basic commands such as sit is very easy using a positive reinforcement method and does not require any more materials than a place to sit and some very yummy treats! When beginning to teach your dog new tricks, starting off in a distraction free area (such as a quiet room in the house) is best. The training can then expand to more distracting places once your dog has the hang of things.

Start by showing your dog a tasty treat and placing it over his or her nose. When they begin to sniff at the treat, gently move the treat backward. Most dogs will follow the treat with their head, and the backward motion will cause their back ends to sit down! Once your dog sits, reward with the treat and some praise. If your dog tends to walk backwards instead of sit, doing this technique against a wall will prevent your dog from walking backward and encourage sitting.

Once your dog has done this a few times, begin to add the word “sit” every time you put the treat above your dog’s head. Only say the word once, and then continue with the luring motion. Your dog will begin to associate the word with the action after several tries! After this, you can begin to attempt to offer the word “sit” once, and if your dog does so, reward with a treat and praise! If your dog forgets, or appears bored, stop training and try again at a later time- most puppies only have an attention span of a few minutes at most!

Q. How do I determine how much my overweight pet should weigh?
ANSWER : A. There are many tools to determine overweight and obesity levels in pets. A new tool, morphometric measurements and body fat index, are available to accurately determine a pet’s ideal weight; this will allow an accurate determination of the amount of food a pet should receive to achieve weight loss. Feeding the correct amount will lead to greater weight loss success.

There are many weight loss food options to help pets reach their ideal weight. Your veterinarian can help make a ideal weight recommendation. Here are some tips to help your dog lose weight in a healthy and safe way:

1. Diet: Providing a healthy and well balanced diet is essential to your pet’s overall health. Finding the right food for your dog can be a challenging process. For those overweight animals many commercial dog companies offer weight loss diets, but it is important to evaluate food labels for adequate nutritional content.

You want to ensure you are not missing other essential vitamin or mineral content. Volume of food is also important and the amount of food that works for one breed of dog may not be the same for another breed of dog. Portion control as opposed to free-choice feeding can help your dog to drop a few unnecessary pounds.

There are also prescription weight loss foods designed by veterinary nutritionists, such as Hill’s r/d (http://bit.ly/1AoENSd). Some pet owners find that home cooking is the best option for helping to provide a well-balanced and realistic diet plan. There are websites such as balanceit.com that offers recipes to fit your dog’s specific needs. Consulting with your veterinarian or a veterinary nutritionist to find the appropriate diet is a great way to help your dog be as healthy as possible.

2. Exercise: Another great tactic for weight loss for your dog is exercise. Whether this is through running, walking or playing with a favorite toy all of these are wonderful types of exercise to help keep your dog at a lean and healthy weight.

For those pet owners with busy schedules utilizing professional dog walking services or playtime through dog daycare services is another option. It has been shown that those pet owners that exercise regularly with their pets generally live a healthier lifestyle.

3. Physical therapy: As animals age pet owners offer encounter their favorite canine having more difficulty walking and have a dwindling desire to play with toys. Physical therapy, specifically hydrotherapy is a wonderful way to help older and arthritic animals gain more mobility and lose weight. Hydrotherapy has been proven to have several therapeutic effects on the body including, muscle strengthening, relief of swelling, decreased joint pain, less stiffness in limbs, improved circulation, weight loss, and increased tissue healing to name a few. For more information on the benefits of hydrotherapy:
http://bit.ly/1w1qqoy

4. Veterinary visit and blood work: Weight gain can also be related to underlying health concerns such as hypothyroidism or other endocrine disorders. Scheduling a veterinary evaluation and routine blood work can be another important component in increasing the longevity of your dog’s life. Conditions such as hypothyroidism that predispose dogs to gain weight can be treated with a daily medication to improve hormonal balance. If feel that your dog is unnecessarily overweight there can be an underlying health condition that needs to be addressed.

5. Healthy treats: Pet owners love the chance to reward their favorite canine companion with treats and most dogs jump at the chance to consume these delicious products. The problem is many treats, which can include commercial dog treats or table scrapes can add many unnecessary calories to your dog’s daily intake. Reading labels and making note of the calories in these treats is an important component of understanding your dog’s overall health. Treats should not exceed more than 10 percent of your pet’s daily calories. There are healthier treats that can be offered to your pet to keep calories lower yet provide a fuller sensation. A pet owner can add steamed or pureed vegetables, such as carrots, green beans or sweet potato to add more fiber and thus a fuller feeling for your dog.

Q. My Beagle listens to me, but cries & whines when I’m gone & doesn’t listen to my parents. I adopted him just a couple days ago. Any tips for my folks?
ANSWER : A. I really highly doubt that your Beagle listens to you and has formed a connection with you in just a couple of days. It takes months to build up any kind of serious connection with your dog. You need to work on communication with your dog through training them to understand different cues. For instance the Leave-It cue: https://www.youtube.com/watch?v=R1TS5nA7z5Q

You have to work on bonding with your dog through mental stimulation. Training is very important. Luring each new behavior from scratch, and training using treats is how you form a strong bond with your new dog. No scolding is ever necessary… work on being calm, and positive, all the time.

If your dog is crying/whining when you leave, this may be separation anxiety. You’re going to have to separation train this dog from scratch. This dog needs to learn that separation can be a good thing! Tell your “folks” to NOT scold the dog when he is crying/whining after you leave, because that will make your dog MORE anxious when you leave next time. Your dog will be dwelling on the negative if your parents fuel your dogs negative feelings towards you leaving. FUN things should happen when you leave. Your parents should pull out the treats and start doing some basic obedience training with your dog. Your parents should stuff a Kong filled with awesome treats (peanut butter) and give it to him so he feels happy when you leave.

I have some excellent separation anxiety exercises you can work on. If you’d like, you can purchase a consultation with me, and I will go over how to separation train from scratch. It will make your dog comfortable being alone, guaranteed.

Read Full Q/A … : I Don't Like My Mother

Q. Whenever I take my dog on walks he always barks at people and others dogs in my neighborhood. What should I do to resolve the problem
ANSWER : A. The very first thing to do is to 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 from boredom or frustration. Depending on his 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.

Figure out what he gets out of barking and remove it. Don’t give your dog the opportunity to continue the barking behavior.

Ignore your dog’s barking for as long as it takes him to stop. That means don’t give him attention at all while he’s barking. Your attention only rewards him for being noisy. Don’t talk to, don’t touch, or even look at him. When he finally quiets, even to take a breath, reward him with a treat. To be successful with this method, you must wait as long as it takes for him to stop barking. Yelling at him is the equivalent of barking with him.

Get your dog accustomed to whatever causes him to bark. Start with whatever makes him bark at a distance. It must be far enough away that he doesn’t bark when he sees it. Feed him lots of good treats. Move the stimulus a little closer (perhaps as little as a few inches or a few feet to start) and feed treats. If the stimulus moves out of sight, stop giving your dog treats. You want your dog to learn that the appearance of the stimulus leads to good things.

Teach your dog the ‘quiet’ command. Oddly, the first step is to teach your dog to bark on command. Give your dog the command to “speak,” wait for him to bark two or three times, and then stick a tasty treat in front of his nose. When he stops barking to sniff the treat, praise him and give him the treat. Repeat until he starts barking as soon as you say “speak.” Once your dog can reliably bark on command, teach him the “quiet” command. In a calm environment with no distractions, tell him to “speak.” When he starts barking, say “quiet” and stick a treat in front of his nose. Praise him for being quiet and give him the treat.

As in all training, always end training on a good note, even if it is just for obeying something very simple, like the ‘sit’ command. If you dog regresses in training, go back to the last thing he did successfully and reinforce that before moving on again. Keep sessions short, 15-20 minutes max, and do this several times a day.

Q. Rescued a dog almost two weeks ago, and now that her kennel cough is gone her personality shines!! No previous training, how should I start?
ANSWER : A. POST FOUR:

After your dog is familiar with the behavior you lured from scratch, and taught to your dog, you can start to use the “no-reward marker” I talked about. What you do is ask the dog to perform the behavior, and if the dog does not perform the behavior, you simply say your no-reward marker (choose one: eh-eh, hey, uh-oh, oops) show them the treat, put it behind your back, and BRIEFLY ignore your dog. Just turn your back for a second or two, before turning back to your dog and saying, “let’s try that again.” When you’re ready to start over with your dog, make sure you move around. If you are repeating the same cue while in the same position, while your dog is in the same position, you are likely to receive the same results. The more you move around, and start fresh, the better your chances are of having your dog listen to your cue the second time around. BIG rewards when they dog it successfully! Lots of praise and treats.

My no-reward marker is “hey.” When my dog does something wrong I say, “hey” and she immediately understands that she needs to offer a different behavior. This is clear to her. I don’t have to say it in a mean way, I simply say, “hey” in a normal tone of voice and she understands what the word means.

Once you’ve built up that connection and communication with your new dog, you can work on all kinds of fun behaviors! I personally enjoy the more zen-like behaviors: https://www.youtube.com/watch?v=ruy9UMcuGh8

I like to teach my dog fun tricks that offer her a “job” to do of sorts like object retrieval: https://www.youtube.com/watch?v=I4iertZSva8

(object retrieval training completed; what it looks like: https://www.youtube.com/watch?v=jx0Dml28FGY)

Scent-games are fun too! Very confidence building. Hide a REALLY smelly treat in a box, and place that box in a line of boxes. Let your dog go in the room while saying something like “search!” or “find it!” and watch them hunt for that smelly treat! Lots of rewards when they find it!

Q. My Bulldog puppy growls, barks and even tries to bite me when I say “no” to him. What can I do?
ANSWER : A. First, avoid scolding him and acting aggressively towards him if you don’t want him to be acting aggressively towards you. There are other methods you can use to communicate to your dog that you don’t want him to continue doing what he is doing. I recommend you stop telling him “no”, scolding him, or raising your voice at him. Everything coming from you should be 100% positive and 100% calm.

Try to figure out ways to clearly communicate what you want to your dog. If you want your dog to leave something or someone alone, I strongly suggest teaching your dog commands like “leave it”. Here is a link to a video in which I explain how to do it:

www.youtube.com/watch?v=R1TS5nA7z5Q

Another thing I suggest you use is a no-reward marker. This clearly communicates when your dog has done something wrong. No-reward markers have to be introduced during your training sessions. You should be doing at least three training sessions per day, that are something like 3-10 minutes long (working on different things each training session). If you are teaching your dog something BRAND NEW, do not use the no-reward marker, as you do not want to discourage your dog from performing behaviors for you. Use the no-reward marker for known behaviors only. Here is another helpful video about this:

www.youtube.com/watch?v=sdU5a6fXKlg

Lure each new behavior (as shown in the video) using high value treats. Let’s say you’re working on “down” which is a behavior your dog knows fairly well. Present the treat to your dog. Ask your dog to “down” (only ask once). If he does not go “down” immediately, say, “uh-oh” or “eh-eh” in a gentle tone, and then place the treat behind your back. This communicates to your dog that they did something to make the treat go away.

After you place the treat behind your back to show your pup “that was wrong” you need to communicate to your pup “let’s try again” by getting your pup to walk around for a second, and then start the behavior all over again. If your puppy is very young, chances are you haven’t taught him a solid “down” behavior yet. So, as I said, do not use this method until you have lured each new behavior as shown in the video.

This is the order in which you should teach behaviors: Lure using a high value treat as shown in the video. After a few successful food lures, lure with an empty hand. If the pup is successful with the empty hand lure, reward with lots of treats. If the pup is unsuccessful, then go back to food-luring a couple more times. After a few successful empty-hand lures, you can begin to add the cue. Say “sit”, then lure with an empty hand, and then reward. Once your pup understands the cue, begin to work on the no-reward marker.

Q. Which common foods are poisonous to pets?
ANSWER : A. That’s a great question. As responsible pet owners we need to be aware of food items that can be harmful to our canine or feline companions. Here are some of the most common foods proven to cause illness in our animals at home:

Chocolate: A favorite and irresistible treat amongst most humans, chocolate is considered toxic to dogs. In very small amounts it is usually not a huge issue, but with larger volumes and with darker chocolates pet owners should be concerned. Chocolate contains methylxanthine theobromine, which is similar to caffeine. Chocolate ingestion can cause vomiting, diarrhea, hyperactivity, issues with normal heartbeats, seizures, and in some severe cases, death. It is best to keep your favorite chocolate treats in a good hiding spot and out of reach of your dog or cat.

Grapes and raisins: Dogs should not consume grapes and raisins because of the risk of acute kidney failure. Most dogs experiencing grape or raisin toxicity will begin to have vomiting and/or diarrhea within 6-12 hours of ingestion. Other abnormal clinical signs include lethargy, abdominal pain, dehydration, and tremors. Kidney failure develops within 24-72 hours of the initial ingestion. There are some dogs that do not experience these devastating side effects. It is best to contact your veterinarian or veterinary emergency facility if you believe your pet has ingested grapes or raisins.

Garlic and onions: We often forget that our meals contain these two popular ingredients and will allow our furry companions a few bites or licks. Onion and garlic both can cause a type of poisoning that results in damage to red blood cells, making them more likely to rupture. They can also cause stomach upset and mouth irritation. Look for pale gums, increased breathing or drooling or any vomiting or diarrhea.

Bread dough: Unbaked bread dough is considered poisonous to our pets. The bread dough, when ingested, expands in the stomach because of the warm and moist environment. This can lead to a bloated or even twisted stomach. In addition yeast is often added to our baking products to help get bread to rise, and when this yeast is fermented it produces both carbon dioxide and alcohol. The alcohol produced can be absorbed into the bloodstream and causes dangerous drops in blood sugar, blood pressure and body temperature. Common clinical signs include vomiting or retching, distension of the stomach, weakness and collapse.

Macadamia nuts: Ingestion of these nuts are not proven to be fatal in dogs but can cause them to experience uncomfortable clinical sings, including fever, joint stiffness, vomiting, tremors and difficulty walking, especially in their hind legs. Often your pet will start to feel better after about 48 hours, but supportive veterinary care (such as pain medication) may help ease their discomfort.

Xylitol: The most common ingredient used in sugar-free gum is xylitol, which is a non-caloric sweetener. It is also found in some oral rinses, toothpastes and vitamins. Xylitol and dogs do not mix – it can cause a dangerous drop in blood sugars levels. Dogs will often display signs of disorientation, black tarry stool, tremors and seizures. If severe enough some dogs have developed liver failure. Keep your gum away from your canine companion.

Avocados: Avocados are not actually poisonous to dogs or cats but as many veterinarians can tell you the avocado pits can cause a foreign body obstruction. Avocados contain persin, which is actually toxic to the majority of pet birds. The abnormal clinical signs associated with avocado ingestion in birds include, respiratory distress, inability to perch, liver and kidney failure and sudden death.

Go forth and enjoy your favorite foods, but keep in mind which foods you should avoid sharing with your furry family members. Whenever in doubt, contact your veterinarian for healthy and safe food suggestions.

Q. How do I desensitize my dog to squirrels and stray cats in the neighborhood?
ANSWER : A. It depends on the goal that you have in mind. I am going to assume that you would prefer that your dog not chase squirrels or stray cats in the yard/street. In this case, your options include: (1) training your dog on a “Leave it ” cue using positive reinforcement methods, (2) training your dog not to pull on its leash when it sees a squirrel/stray cat, and (3) training your dog to perform a more desirable behavior when it sees a squirrel/cat.
Training your dog on a cued “leave it” command is useful because it will give you the ability to tell your dog to stay away from any number of undesirable objects on your command. Training your dog to perform a more desireable behavior when it sees a squirrel or cat will substitute a behavior you find acceptable (sitting, laying down, coming to the door, etc.) with a behavior you dislike. Your dog can still react, just in a positive way. If your dog pulls on the leash every time you see a squirrel/cat, training not to pull will make your walk safer and more pleasant.
The ideal training method to use with dogs, or any animal for that matter, is positive reinforcement training, particularly a method called “clicker- training.” The basic concept of positive reinforcement training is to pair a reward (reinforcement) with a behavior you want to increase in frequency. In other words, when your dog performs the behavior you desire, it receives an award, which reinforces the desired behavior so you get more of that behavior. There are many excellent books in stores or on-line that describe positive reinforcement training in detail and many give step-by-step instructions for training common commands like “leave it”. Look for books that specifically mention positive reinforcement training or clicker-training. You can also take dog training classes to learn the techniques, find a mentor who already uses clicker-training, or request a consult from one of the pet experts on this site to guide you.