Experienced and professional animal trainer provide their insights in answering this question :
A. It could be infection, female dog in season. If it is affecting the leg too it is more likely to be infection or soft tissue swelling. It is likely to be painful so I would recommend seeing your vet as soon as possible.

How to Identify Common Pet Problems ?

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

It is very normal for a dog`s nipples to swell after heat as her body adjusts to fluctuating hormones. However, it is also the most common sign of a pregnancy or phantom pregnancy. So, if you notice swollen nipples and other suspicious changes, it`s best to see a vet to rule out underlying problems.
The fall of progesterone triggers a rise in prolactin, a mammary-stimulating hormone. It`s normal for dogs at this stage to have swollen nipples, even when there is no pregnancy.
If your dog is diagnosed with mastitis, oral antibiotics and anti-inflammatory medications will most likely be prescribed. Mastitis does not typically require hospitalization unless your dog has become septic or requires surgical removal of severely affected glands.
The most common clinical sign of benign mammary tumors is one (or more) masses that you can feel underneath the skin of your dog`s lower chest or belly. They may be next to or within the nipple and follow along the mammary chain (see illustration).
This leads to illness and poor quality of life, with survival times usually less than one year. Dogs with inflammatory mammary carcinoma and mammary sarcomas have a poor prognosis, on the order of weeks to months. Early detection of tumors is key for long-term survival.
Yes, both male and female dogs have nipples. These small bumps extend from their groin area up their stomachs, and the number of nipples can vary. Dogs tend to have between 8 and 10 nipples, but some have more, while others have fewer nipples.
Physically, dogs that are experiencing a false pregnancy go through changes to prepare for puppies to be born. Their mammary glands (breasts) and nipples enlarge evenly, and they may even produce some milk. This swelling can be uncomfortable, so your dog might lick at the glands, causing irritation.
Signs a Female Is in Heat

Swollen nipples – Sometimes, but not always, the nipples and breasts will swell slightly. This can also be a sign of a phantom pregnancy, when a female may begin to show signs of being pregnant even if she`s not.

The causes range from harmless to serious. Premenstrual syndrome (PMS) is one common cause of breast swelling. Before the start of each period, your estrogen production increases. Along with other changes in your body, this hormonal shift can cause your breast ducts and milk glands to become enlarged.
Mastitis is inflammation and infection in a mammary gland. It`s a very painful condition that causes swelling, redness, and often discharge from the nipple. Mastitis is most common in lactating dogs, and those having a phantom pregnancy.
Surgical removal is recommended for most mammary tumors. Chemotherapy may be required following surgery in some cases. The prognosis is good following surgical resection for most mammary tumors in female dogs, but the prognosis is worse for certain types of tumors in dogs and all mammary tumors in cats.
It could appear as a hard or soft lump in the mammary gland area. At first, it will be covered with skin and hair. If advanced it could burst and look like an abscess . It is important for every owner of a female dog check out mammary area for lumps regularly since this is a frequently occurring cancer in canines.
Studies show that even though breast cancer happens more often now than it did in the past, it doesn`t grow any faster than it did decades ago. On average, breast cancers double in size every 180 days, or about every 6 months. Still, the rate of growth for any specific cancer will depend on many factors.
The gold-star treatment for mammary tumors is surgery. In most cases, the surgeon will remove the tumor itself or the entire affected mammary gland. It is uncommon to remove the entire mammary chain in dogs. Surgery usually is not recommended with inflammatory or metastatic cancer.
Adding supplements for mammary tumors in dogs, such as medicinal mushrooms, curcumin, CoQ10 and fish oil, can support your dog`s immune system and overall well-being. Feeding a low carbohydrate cancer diet rich in omega-3s and fresh nutrients can also help.
Enlarged or Discolored Nipples

While a female dog`s nipples are normally small, pregnancy causes her nipples to grow in size during the early stages of pregnancy. The areolas also become somewhat rounded compared to their usual flatness.

The cost of treating dog mammary tumors is going to vary depending on the number and size of the tumors, and your location. For a single small tumor, costs may be as low as $500 for diagnostics and surgery. For larger or multiple tumors, that price is going to increase to $1,000-$3,000 or more.
When a dog is in heat (receptive to mating), her vulva becomes swollen, and a bloody discharge will be evident. This heat period usually lasts for a week or two but can vary widely between dogs. After being in heat, the bleeding should stop, and the vulva returns to its normal appearance.
Thankfully, there are relatively safe means to prevent pregnancy after mating. One such option is known as a `mis-mating injection. ` If you suspect your dog mated in the last 22 days, then an injection of Alizin, an antiprogestagenic compound, may be an option.
Female dogs spontaneously produce milk when they have given birth to puppies. This is a normal part of biological parenthood for any female mammal. Female dogs may also produce milk when experiencing a false pregnancy or when another creature attempts to nurse from her.
Symptoms of breast cancer in dogs include a straw-colored, pus-like, or bloody discharge from the nipple and the presence of small or large nodules within the dog`s breast. Mammary tumors are most often seen in the inguinal glands close to the legs. Breast cancer is diagnosed by fine-needle aspiration.
How long are dogs pregnant for? – A dog pregnancy can vary between 56 – 70 days. Typically, puppies should arrive about 63 days (just over 2 months) after conception.
See your doctor if the pain doesn`t improve or you notice any of these signs: Severe swelling. A lump in the breast. Redness and warmth, which could indicate an infection.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

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. 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 dog licks his feet and legs and they are turning brown. He is a white dog. Can you help?
ANSWER : A. Licking the feet and legs can be caused by a number of things in dogs including allergies, illness or even stress behaviors. Allergies are the most common in dogs, with yeast infections coming in second. Allergies can cause the area to become red and itching, making your dog want to lick and chew on them. Over time, the area may become stained from saliva, especially in lighter or white-coated dogs. Yeast infections are also common between the toes, and may cause a smelly “corn chip” smell to appear near your dog’s feet. Again, dogs will attempt to lick and chew to relieve the itch. Keeping the feet clean and dry can help relieve both allergies and infections and pet wipes or a baby wipe of all paws when your dog comes in from outdoors may also help. Keeping your dog from licking the space with either dog booties or an Elizabethan collar is also good as it will prevent secondary infection and staining of the paws and legs. If your dog is determined to keep licking and keeping the feet clean and dry do not help, then your vet can help by providing a medication to treat any infection or provide relief of allergies.

Q. Why does my dog eat grass?
ANSWER : A. As another user mentioned, dogs can eat grass when they want to vomit. Sometimes, when a dog has an upset tummy, they will eat grass. If you notice your dog eating grass frantically, you can assume vomiting will shortly follow. Grass does not digest and pass normally. If your dog eats too much grass, it can cause serious issues with pooping. Your dogs poop can end up all tangled inside of her, and it can need veterinary assistance to remove it. The same goes for celery, so avoid feeding celery to your dog.

The other day my boyfriend accidentally left the laundry room door open where we were keeping the trash that was filled with cooked chicken bones. She ate one of the chicken bones lightning fast. We had to induce vomiting by feeding her some hydrogen peroxide. After we had fed her the peroxide, she immediately began frantically eating grass because her tummy was upset.

If there is something lacking in your dogs diet, it could be that your dog is eating grass to make up for it. I am sure that my dogs diet is extremely well balanced (I do not only feed her an air-dried raw food-type diet (Ziwipeak), but a wide variety of safe, healthy foods), so when she eats grass, I know that it is because she has an upset tummy.

That is why I think it is important making sure your dog has a very well balanced diet. If your dog is on a low quality kibble, your dog may be trying to let you know by eating grass (or eating poop).

Q. Hi Antwannn here: I have a question about my dog, My question is, what make a dog nipples swell? my dog has these swollen nipples and leg
ANSWER : A. It could be infection, female dog in season. If it is affecting the leg too it is more likely to be infection or soft tissue swelling. It is likely to be painful so I would recommend seeing your vet as soon as possible.

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. My 4 year old Chihuahua mix began having a series shaking/panting episodes (last 15m- 1hr) out of the blue. Vet’s tests say its not physical.
ANSWER : A. There are many causes for shaking/panting. The shaking and panting are both signs of stress, and your dog may be dealing with anxiety, or stress, related to an event that happened, or is happening. I realize you cannot answer questions on this, however, I will ask some questions that you can ask yourself. Have you recently moved? Have you ever hit or yelled at your dog? Has the weather been bad lately (storms)? Have you had any new guests stay over recently? Have you had any dogs come to your home recently? Have you had any dogs or cats in your yard recently? Was your dog frightened by something initially (a falling pot/pan; a loud bang from the washing machine; a gunshot; a backfiring car/truck; someone screaming in your home/a fight)?

If you answered yes to any of those questions, it could definitely be that. Dogs don’t typically hang on to something for very long, but if it really frightened your pup, then she/he could be feeling serious anxiety related to that specific event, and relating other events to that one.

Do not yell, or hit your dog. I’m not assuming you do, but if you do, please stop doing that right away. It could be that your dog is afraid of you specifically, and you notice the shaking/panting when you are near, because that is the only time your dog is doing it.

If you’d like to purchase a consultation with me (I know, it’s a lot to ask, but I really feel like I could help) I’d be more than happy to ask you many questions, and together we can figure out what the heck is going on here. It’s important that your dog is comfortable, and if your pup is always feeling anxious/uneasy, then his/her quality of life is in jeopardy.