Experienced and professional animal trainer provide their insights in answering this question :
A. You can try tempting to eat with some cooked chicken served warm as this can encourage eating. If he is still not interested then it would be wise to have him checked over by your vet incase any other tumors have appeared.

How to Identify Common Pet Problems ?

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

Decreased appetite: Nausea may be associated with cancers of many types and causes a decrease in appetite with subsequent weight loss. Direct effects of the tumor: Some tumors, because of their location in the mouth, throat or intestinal tract may make eating, swallowing, or the digestion of food difficult.
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.
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.

Chemotherapy affects rapidly reproducing cells. Cancer cells are the intended target, but the cells that line the stomach and intestines are also rapidly dividing and can be affected. The result is often nausea, vomiting, and diarrhea which typically decreases a dog`s appetite and food consumption.
Changes in appetite—either increased or decreased—can be subtle signs of cancer in dogs and cats. If a pet is feeling yucky or is in pain, then they may not want to eat. Conversely, other cancers can cause a pet to eat more than normal. Some cancers consume a lot of calories, which will increase a pet`s appetite.
Signs of Pain in Dogs with Cancer

It may sound vague, however if your dog begins displaying any behavior that is not typical for them, it could be an indication of pain. Some of the most common signs of pain in dogs include: Limping. Loss of appetite.

This trauma causes the tumor cells to release the chemicals in their granules leading to a localized reaction. In more serious cases, the chemicals can affect the entire body, causing severe gastrointestinal bleeding and even an anaphylactic reaction, which can be fatal if untreated.
With surgery alone, the median survival (50% alive) is 6 months. With surgery followed by chemotherapy, the median survival increases to 12 months. In case of incompletely excised grade III tumors, we recommend either a second surgery or radiation therapy.
Stages of mast cell tumors in dogs

Stage I – Single tumor without metastasis. Stage II – Single tumor with metastasis into the surrounding lymph nodes causing secondary growth. Stage III – Multiple skin tumors, or a large tumor that has invaded the subcutaneous tissues. There may or may not be lymph node involvement.

Most seem to be caused by a complex mix of risk factors, some environmental and some genetic or hereditary. Several genetic mutations are known to be involved in the development of MCTs. One well-known mutation is to a protein, called KIT, that is involved in the replication and division of cells.
As we know, senior dogs are susceptible to a variety of systemic illnesses as they age. Kidney disease, liver disease, diabetes, and even cancer can all cause decreased appetite.
If your dog is not eating at all, there is a good chance they are close to the end. As your dog`s digestive organs shut down, they will not experience the sensation of hunger or thirst. Visible weight loss will often accompany this decrease in appetite.
Sad and stressed dogs may also not want to eat or drink. “They may also stop eating their food, but will eat people food,” says Ochoa. So, look for any change from the normal diet and cravings.
Extreme fatigue: Your normally active dog or cat may seem depressed and take no interest in exercise or play. It`s also common for a pet with cancer to sleep several more hours per day than usual.
Additional symptoms of canine cancers may include:

Coughing or exercise intolerance. Lethargy. Bleeding or discharge from any body opening. Difficulty eating or swallowing.

Many dogs with cancer will show no signs, at least initially. In other dogs, signs may be vague. Once a dog becomes sick enough, signs can be quite severe and seem to have a sudden onset. Routine wellness visits and health screening tests can help your vet detect illness early.
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.
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.
Tumors need sugar for energy. To counteract this process, dog owners must choose a diet high in fat and low in carbohydrates for their dogs; this way, as numerous documented cases testify, your dog`s body will literally starve tumors out, impeding them from metastasizing!
Roughly 20% of all skin tumors found in dogs are diagnosed as MCTs. Not all mast cell tumors are malignant (cancerous). Fortunately, though, malignant MCTs are among the easiest types of cancer to treat.
Mast cell tumors can grow slowly over time, or develop very rapidly, seemingly overnight. Mast cell tumors in cats are found on the skin (cutaneous MCTs) in most cases, typically appearing on the head and neck—but can appear anywhere on the body.
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.
SYMPTOMS OF CANINE MAST CELL TUMORS

Affected dogs may experience fatigue, decreased appetite, increased respiration, diarrhea, or vomiting.

Surgery remains the mainstay treatment for mast cell tumors, however, it depends upon the grade and stage of the tumor. For grade I and most grade II mast cell tumors, wide surgical excision is generally considered to be a curative treatment.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. My puppy refuses to walk outside on the leash. This only happens when we’re outside… Is it stubbornness or fear?
ANSWER : A. It is never stubbornness. Dogs are not stubborn, they can’t be. Dogs do not generalize well, and dogs display fearful behavior that appears to be stubbornness. Absolutely NEVER force this dog to walk outside when he is uncomfortable with doing so.. the more you force him to do it, opposition reflex – the more he will resist. The more he resists and is forced into it, the less he learns about being comfortable, and the more he becomes fearful of you and of the situation.

What you can do is carry extremely high value treats outside with you. Things like cooked white meat chicken, cooked fish, turkey pepperoni, turkey bacon, diced ham, mozzarella cheese sticks – all cut up into tiny little pea-sized pieces. You can also use peanut butter in a squeeze tube. First, put on the leash indoors and begin feeding him the treats. Help him make positive associations with having the leash put on. Then, take the leash off, and start over in 10min. Put the leash on, feed treats, walk to the door, open the door, feed treats, close door, take off leash. Start over in 10min. Put on leash, feed treats, go to door, feed treats, open door, feed treats, go outside, feed tons of treats and praise. Keep Titus in his comfort zone. If he doesn’t want to go far, just feed him tons of treats where he IS comfortable going. Make sure everything is calm/happy/positive. I bet in a week of doing this, he will be happy with walk further and further all of the time. If ever he is uncomfortable, feed him lots of treats for being a brave boy, and then turn around and go back home. It’s all about keeping him in his comfort zone.. it’s all about remaining within his threshold and never forcing him to feed uncomfortable.

This is very common for puppies. The world is scary! It’s brand new to them, and it’s up to you to make their interactions and discoveries positive, happy, calm, and to never force them into anything.

Q. My 11 year old pug’s appetite is suddenly poor. I must hand feed him. He was diagnosed and treated for mast cell cancer one year ago.
ANSWER : A. You can try tempting to eat with some cooked chicken served warm as this can encourage eating. If he is still not interested then it would be wise to have him checked over by your vet incase any other tumors have appeared.

Read Full Q/A … : Loss Of Appetite – PugSpot

Q. What’s the best way to train a dog to use a lead again?
ANSWER : A. It depends on how serious your issue is. If you need to start from scratch: Bring out the leash, place it on the ground. Click and treat your dog. Say his name, work on attention, click and treat for attention. Work with the cheese sticks, or with some chicken.. something stinky, soft, and high value. Allow him to sniff the leash, praise him, click, treat, click, treat. Pick up the leash, click treat him. Hook the leash to his collar and allow the leash to drag, click treat him. Have him just follow you around, click and treat him to hold his attention.

Then, pick up the leash, click and treat him. Then drop the leash again, click and treat. Take baby steps. Then, hold the leash while you take a step, click and treat him for following. Open the front door, click and treat him. Then, take off the leash, click and treat him, and end training.

Pick training back up in an hour, and do the same exact thing from start to finish, only this time, “finish” will be you two going outside, you clicking and treating him a bunch, and then you bringing him back inside. Work your way up slowly. You can’t expect to just bring him outside and bring him on a walk right away.

When outdoors, use a front hooking harness like the Sensible/Sensation harnesses: http://www.softouchconcepts.com/index.php/product-53/sense-ible-harness / http://www.softouchconcepts.com/index.php/product-53/sense-ation-harness. These harnesses will eliminate the pulling power of your pup in a positive way. This will put you in control without the use of force. Carry high value treats with you everywhere, and offer them for good walking behavior – treats like white meat chicken, cooked fish, turkey pepperoni, turkey bacon, diced ham, mozzarella cheese sticks, hotdogs, all cut into tiny little pieces. The more you work on walking on-leash/attention indoors, the better it will be outdoors, remember that.

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. We have a 4 yr old lab-pit mix we raise from 6 weeks.If my husband tries to take hin by the collar and make him go out to pottie he growls.Problem?
ANSWER : A. This is not good behavior. Rather than take him by the collar, call him to come with you. If he’s not good about coming when called, you can work on that. Keeps treats on hand to to entice him out and reward him when he does go potty and he’ll come to look forward to it. Clicker training is another great way to teach a dog all kinds of things, from obedience to tricks.

Have treats on hand that you know he loves, then simply click and treat. He will come to associate the sound with getting a treat. Start putting distance between you so he has to come to you. Call and click and when he comes to you for that treat, treat him and give him lots of praise. Move to hiding somewhere in the house, call and click. When he comes to you reliably inside when you call, click and treat. When this behavior is consistent, move outdoors with a very long leash. Call and click, if he doesn’t respond, give a light tug on the leash. If he takes even a single step toward you, click, treat and lots of praise. Keep doing this until he comes eagerly. Next, try him off-leash in a securely fenced area. Call and click. At this point he should be responding well and coming easily to the call and click. If he does not, go back to the last step he performed reliably and work on that again until he responds well. Eventually, you can start not treating him every time, but still praise him. Gradually lessen the frequency of the treats until he comes just to the click and praise.

Keep training sessions short, ten or fifteen minutes to start, no more than 30 minutes at a time and do it a few times a day. Try not to do it any time he is overly excited so that he can pay attention to you. Always end a training session on a good note, even if it is just getting him to do something he already does well on command. And never, NEVER punish a dog when they come to you, no matter how far they’ve made you chase them, no matter how frustrated and angry you might be. That teaches your dog that coming to you is a bad thing.

Read Full Q/A … : Causes of Limping in Dogs

Q. I have a 8 month old Lab. He gets excited and likes to get mouthy and puts the persons hands in his mouth. Doesn’t bite hard. How can we stop this?
ANSWER : A. Bite inhibition is a great way to stop mouthiness that occurs often with teenaged dogs. There are several training techniques that can be done to help teach your dog how to play nicely! One is to teach a “Leave-it” command. Begin by holding a treat in your hand and asking your dog to “leave it”. If he attempts to chew or bite, a high-pitched YELP! will help. Once he backs away or ignores the treat, ask him to “take it” and offer it to him. Another useful way to teach bite inhibition is through the use of a tug toy. Again, the “take it” and “leave it” commands are used. During a tug session, ask your dog to “leave it” or “drop” and exchange with a treat. If he lets go of the toy, reward him! One final option is also “airplaning” treats. This method involves having your dog sit and then slowly lowering a treat toward him. If he goes for the treat, back away and start over. Once he can sit calmly and not chew on you, reward with the treat! All of these techniques are great for helping teach dogs bite inhibition. 🙂

Read Full Q/A … : Leerburg

Q. I’m almost positive my dog is afraid of the dark! Every time I turn off the light she starts crying! Is there a way I can teach her not to be afraid
ANSWER : A. You may need to take things very slowly. First off, you should consider using a night light in the room you have your dog in. I have a night light in my room for my dog, even though I don’t feel the need to use one. You should have a handful of treats, and toss several of them to your dog. While your dog is eating the treats, shut off the light, and then turn it back on and toss several more treats to your dog. While your dog is eating the treats, turn off the light and count to three, then turn it back on. Toss several more treats to your dog, turn off the light and count to five. Turn the light back on, toss several more treats to your dog, shut off the light, count to four. Turn on the light, toss treats, turn off light, count to eight. Turn on light, toss treats, turn off light, count to five. The key is to randomly increase and decrease the amount of time the pup is in the dark. Work on it slowly, slowly build duration. Do not expect it to happen all in one session.

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.