Experienced and professional animal trainer provide their insights in answering this question :
A. I would get it checked by vet because it will need a biopsy to see if it is cancer or not. And if it needs removing the bigger it gets the harder it is to remove.

How to Identify Common Pet Problems ?

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

Some common causes include fat, tumors (benign and malignantVery virulent or infectious.), cysts, infection (abscess), allergic reactions and swelling from injury or hernia. A hernia occurs when one tissue or organ protrudes through another into an abnormal place on the body, often causing a lump or bump.
In dogs, the most common type of malignant skin cancer is a mast cell tumor. These tumors are superficial lumps that can be painful. They often swell, frequently bleed and then scab over, only to bleed again a few days later. They should not be squeezed by the owner, as squeezing can make them swell even more.
Jamie Whittenburg (DVM) explains, “All masses grow from just a few microscopic cells into larger masses that may be felt on the dog. A `sudden` appearance of a mass or lump may be the owner just finding the mass for the first time, a very aggressive cancer, or even a cyst, seroma, or abscess filling with fluid.
Lipoma. The most common benign lump that dogs develop, a lipoma is a fat-filled tumor found under the skin of middle-aged or older dogs and is considered a natural part of aging. These soft, rounded, non-painful masses grow slowly and rarely spread.
Sudden lumps on a dog can be caused by anything from allergies, infections or even tumors. There is no way to know what the sudden lump may be without going into your dogs body and looking it over closely.
A hygroma is a fluid-filled sac that develops over bony prominences and pressure points, especially in large breeds of dogs. Repeated trauma from lying on hard surfaces leads to inflammation. This results in a dense-walled, fluid-filled cavity.
They can feel firm or soft. Benign masses are more likely to be painful to the touch, such as with an abscess. Benign tumors also tend to grow more slowly, and many are smaller than 5 cm (2 inches) at their longest point. Sarcomas (cancerous growths) more often are painless.
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.
Histiocytomas are an abnormal growth of immune cells in the skin, and are often seen on young dogs. These masses can look angry, because of their bright red color and “bubbled” surface. They often appear overnight and sometimes will disappear without treatment.
The most common clinical sign of this tumor is a mass in the neck. Other signs usually are attributable to the tumor affecting the nerves of the voice box and may include a change in the tone of the bark, harsh breathing sounds, difficulty breathing and rapid breathing.
One of the best ways to identify a potentially cancerous lump is to evaluate how that tumor feels when touched. Compared to the soft, fatty characteristics of a lipoma, a cancerous lump will be harder and firm to the touch, appearing as a hard immovable lump on your dog.
Sometimes lumps can appear on dogs overnight — if they don`t seem to bother your pet, you can monitor the growth at home until your next vet visit. But, if your dog starts licking or scratching the bump, or it changes in appearance, contact your vet as soon as possible.
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.
They are extremely common growths that are most often found in the tissue layers below a dog`s skin. Lipomas in dogs are benign, noncancerous tumors that grow from fat cells. They are more common in overweight dogs and are more likely to develop as a dog ages.
Sebaceous cysts appear as a single raised bump that may seem white or slightly blue in color. If it bursts, it will ooze a grayish white, brownish, or cottage-cheese-like discharge. These cysts usually develop on the head, neck, torso, or upper legs.
A lump in the neck may be a sign of thyroid cancer. Or it may be caused by an enlarged lymph node. Swelling in one or more lymph nodes in the neck is a common symptom of head and neck cancer, including mouth cancer and salivary gland cancer. Lumps that come and go are not typically due to cancer.
As a tumor grows it can compress adjacent nerves and organs, resulting in pain.
If the lump has solid components, due to tissue rather than liquid or air, it could be either benign or malignant. However, the only way to confirm whether a cyst or tumor is cancerous is to have it biopsied by your doctor. This involves surgically removing some or all of the lump.
Lump on neck

Your neck is home to your thyroid gland, which can form benign solid or fluid-filled lumps at the base of the neck near the collarbone. Most thyroid lumps are benign, but they can form rapidly so it is important to see your provider for regular examinations. Cancerous lumps are hard and painless.

Lumps in the muscles of the neck are caused by injury or spasm of the neck muscles (torticollis). These lumps are often at the front of the neck. Lumps in the skin or just below the skin are often caused by cysts, such as sebaceous cysts. The thyroid gland may also produce swelling or one or more lumps.
A hard, immovable lump on your dog is a sign that you must book an appointment at the vet as soon as possible. If your dog is also suffering from any of the following symptoms, then it`s time to call the vet: The sudden appearance of lumps. Changes in size, colour, or texture.
Dog Cyst vs Tumor: How Do I Tell The Difference? Cysts are fluid-filled sacs under the skin that are usually easy to move around, while tumors are typically more solid. A cyst also may drain a white, yellow, or green discharge.
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.
As many as 50% of pets die of cancer. An estimated 6,000,000 dogs and nearly 6,000,000 cats will be diagnosed with cancer this year. In many of these animals, the malignancy will look and behave much as it would in humans, such as spreading to the same organs.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

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. 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. 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. What can I do to stop my dog from barking at people and front doors?
ANSWER : A. Ignore your dog’s barking for as long as it takes him to stop. This means don’t give him any attention at all while he’s barking. Your attention only rewards him for being noisy. Don’t talk to him, don’t touch him, and don’t even look at him. When he finally quiets down, 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. If he barks for an hour and you finally get so frustrated that you yell at him to be quiet, the next time he’ll probably bark for an hour and a half. Dogs learns that if they bark long enough you’ll give them attention.

Teach your dog the ‘quiet’ command. It may sound nonsensical, but 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.

When your dog starts barking, ask him to do something that’s incompatible with barking. Teach your dog to react to barking stimuli with something that inhibits him from barking, such as lying down in his bed.

Make sure your dog is getting sufficient physical and mental exercise every day. A tired dog is a good 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 fetch and playing with interactive toys.

Q. My 4 yr old male Catahoula Leopard Dog mix is a rescue. He’s become very possessive of me around larger dogs. How can I correct this behavior?
ANSWER : A. Sudden behavior changes can sometimes indicate an underlying health issue, so scheduling a checkup with your regular vet is always the first step. Once any health issues have been addressed, then you can address the behavioral ones. It is very common for dogs to become “possessive” of people or objects when around other dogs or people, and is called location guarding. Possession of objects or places can be a little easier to manage, however possession around other dogs can be treated as well. Working from a distance in a technique called BAT or Behavioral Adjustment Training may help. This technique involves your dog and another calm dog. Start off at a far distance and then move in until your dog becomes reactive or wary of the other dog. Move back a small amount and wait for your dog to become calm. If he shows calm behavior, reward with lots of praise, treats and love! If he becomes agitated or possessive, move back until he is calm, or stop the session completely and try again later. While this may take some time, it can help dogs learn that other dogs are not a threat to them or their people. Reading more information about BAT training or contacting a local trainer in your area can help with further advice and techniques!

Q. Sudden unexplained huge lump on dog at back of neck; not painful; not restricting movement. Hard and firm to the touch. Dog in good health.
ANSWER : A. I would get it checked by vet because it will need a biopsy to see if it is cancer or not. And if it needs removing the bigger it gets the harder it is to remove.

Q. Husband shamed dog for having an accident inside, and now she won’t poop when he takes her out. Can we fix this? He realizes he erred
ANSWER : A. Good on your husband for realizing that scolding is not the way to potty train! Hopefully these tips can help both him and your pup get back on the right track and make pottying outside successful.

If your dog is still a puppy, that is good news as you may be able to more easily time your potty outings with your dog’s schedule. Even if your dog is older, this schedule may help. Dogs generally have to go potty about 15 minutes after eating, drinking, waking up or playing. Knowing this, get your husband to start taking out your puppy at these key times, so puppy gets used to going out with him, and the urge to potty may be higher than any fear to go. If the potty is successful, have your husband reward the dog with a favorite treat! For bowel movements, dogs may take a little more time, and you may have to stand outside for a while (sometimes even 10 minutes) to give your dog a chance to go. If she doesn’t go, take her back inside and play some, then try again in about 15 minutes. Again, a success equals a treat which most dogs will like right away!

For any indoor potty accidents that occurred, an enzymatic cleaner is great for cleaning up urine and stool. Not only does it remove the stain and smell, but it breaks down the enzymes in the urine and stool your dog can smell, which may deter her from going potty there again.

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.