Experienced and professional animal trainer provide their insights in answering this question :
A. Puppies pick up all sorts of bugs. As he is still so little and is vomiting and appears to be losing weight then I would recommend having him checked over today by your vet.

How to Identify Common Pet Problems ?

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

THe most common reasons a puppy may refuse to eat include: stress and anxiety, environmental issues, digestive issues, illnesses, teething pain, and food preferences. If your puppy refuses to eat, it`s important to consult with a veterinarian who can diagnose and provide appropriate treatment.
Infections, illnesses, and pain can make your dog tired, listless and uninterested in food. When these symptoms continue for more than 24 hours, they could indicate the presence of a health issue that requires a visit to our veterinary hospital in Diamond Bar.
Most cases of diarrhoea in dogs are not serious and dogs will get better by themselves. But if your dog has diarrhoea and other symptoms, such as frequent vomiting, lack of appetite, lethargy or bloody diarrhoea, contact your vet or find your nearest emergency vet.
The most common causes of lethargy in dogs are: Infection, including parvovirus, distemper, kennel cough and leptospirosis. Metabolic diseases, such as heart problems, liver problems, diabetes, and hypoglycaemia. Medications, such as newly prescribed drugs or a new flea or worm product.
Some of the signs of parvovirus include lethargy; loss of appetite; abdominal pain and bloating; fever or low body temperature (hypothermia); vomiting; and severe, often bloody, diarrhea. Persistent vomiting and diarrhea can cause rapid dehydration, and damage to the intestines and immune system can cause septic shock.
Bladder infections or urinary tract infections are two major culprits of reduced thirst. It could also be diabetes or kidney disease. If you notice other symptoms like lethargy and lack of appetite, and feel like something might be wrong, it`s important to call your veterinarian and discuss what`s going on.
Distemper (aka canine distemper) is caused by a virus. It can infect dogs, raccoons, skunks, foxes, and large cats such as lions and tigers. The virus infects the lungs, airways, nose, and eyes. It can also infect the brain and suppress the immune system. Distemper can cause serious illness and death in these animals.
It could be that your dog ate more than they could handle or ate too fast, or your dog could have eaten too much grass. Sometimes the cause could be more serious. Your dog could have swallowed something toxic, or it may be a sign of a serious illness, which could require a visit to see your vet.
In the early stages of dehydration, your dog is likely to exhibit visible symptoms such as being apprehensive or acting noticeably tired. He or she may pant excessively which can actually cause additional fluid loss. Sunken eyes, dry noses, and dry gums are also possible.
Keep an Eye on Your Puppy

If your puppy is just tired, then they should recover after some rest. This may just be a nap or it might be a good night`s sleep. Tiredness alone isn`t typically a sign that you should worry. However, if your puppy seems tired for a few days straight, then that may be cause for concern.

There are a few reasons a dog may become quieter than usual: pain, stress, or boredom. While a quieter dog may not feel like such a “problem” to us, it`s important to make sure their behavior change isn`t a sign of a bigger medical or behavioral issue.
The first sign of parvo for puppies is often lethargy, lack of appetite, and a fever. Canines will begin to suffer from vomiting and diarrhea as the virus progresses, and can experience dehydration and a high heart rate as a result.
When signs of parvo start showing, the stool gets more watery, becoming brownish to black diarrhea with traces of blood. After signs of parvo start to show and diarrhea gets bloody and smelly, it`s a race against time because most dog fatalities happen within 2 to 3 days after the symptoms.
Dogs with pancreatitis, parvovirus, or leptospirosis tend not to drink much water, but a brewing bladder infection, other types of infection, or a metabolic problem such as Cushing`s disease, and diabetes can cause excessive thirst and water consumption.
Little or negative socialization

You might find your dog become aggressive, shy, or fearful around other humans or animals. Lack of socialization may even cause depression spells. You may witness your dog develop irregular sleeping and eating patterns, or it may refuse to play.

Initially, infected dogs will develop watery to pus-like discharge from their eyes. They then develop fever, nasal discharge, coughing, lethargy, reduced appetite, and vomiting.
When a dog is coming down with distemper, the first signs that an owner typically notices include drainage from the nose and eyes, coughing, and difficulty breathing. Most dogs will also have a fever, be somewhat lethargic, and will not be eating well, if they are eating at all.
Initial symptoms of canine distemper include an elevated body temperature (above 103.5°F or 39.7°C), reddened eyes and a watery discharge from the nose and eyes. More developed symptoms include lethargy, tiredness and eventually anorexia. At this stage, coughing, vomiting and diarrhea may also occur.
Although a loss of appetite in dogs doesn`t necessarily indicate serious disease, prompt veterinary attention is important because it could be a sign of significant illness, including cancer, various systemic infections, pain, liver problems, and kidney failure. Dental disease.
Can a dog pass an intestinal blockage? Sometimes. If the blockage is caused by a foreign body, the dog can often pass it through the gastrointestinal tract and out in the stool.
Acute pancreatitis can occur after a dog eats a fatty food such as pork, beef, and some other human foods. Dogs that get into garbage can develop pancreatitis. Pancreatitis can also have other causes, including certain medications and some viral or bacterial infections.
What are the typical signs of pain in dogs? General behaviour: Shaking, flattened ears, low posture, aggression, grumpy temperament, panting or crying, excessive licking or scratching a specific area, reluctant to play, interact or exercise, lameness (limping), stiffness after rest, loss of appetite.
Hypoadrenocorticism is an uncommon disease in dogs, and it is caused by a deficiency of essential hormones that are made by the adrenal glands. Also known as Addison`s disease, the clinical signs may appear as vague signs of illness that come and go.

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. My 2month old puppy behavior has changed he is not playful not eating hardly drinking water and losing weight and vomiting and, a runny nose
ANSWER : A. Puppies pick up all sorts of bugs. As he is still so little and is vomiting and appears to be losing weight then I would recommend having him checked over today by your vet.

Q. My dog drinks a lot of water, should I worry?
ANSWER : A. Firstly, you should quantify if your dog is actually drinking an excessive amount of water. In a 24 hour period, a dog should drink about 1 fluid ounce (or 30mL) per pound of body weight. Therefore, the recommended amount of water intake (in fluid ounces) equals your dog’s weight (in pounds). For example, if your dog weighs 8 pounds, he/she should drink about a cup of water in a 1 hour period. This will be slightly increased if your dog gets a lot of physical activity or lives outdoors.

You can measure your dog’s water intake the following way: in the morning, measure a specific amount, a little bit more than you think he/she will drink. 24 hours later, measure the remaining amount. If the amount of water your dog drank is significantly greater than it should be, then you should take your dog to a veterinarian.

Causes for mildly increased water consumption include: food changes, increased ambient and body temperature, increased activity, urinary tract infection, and general illness.

Common causes for greatly increased water consumption include: diabetes, urinary tract infection, kidney disease, steroid use, and other systemic diseases. With large increases in water consumption, you will also usually see increased urination. Please take note of urinary patterns to discuss with your vet. Greatly increased drinking and urination is ALWAYS a reason to see a vet.

Q. How do I get my dog to stop chewing on things? I kennel her when I leave for a few hours, but I can’t go to the mailbox without her eating something.
ANSWER : A. If she’s young, then this is just normal puppy behavior. Don’t worry about it. The thing about puppies is, they explore using their mouths. If your puppy grabs a coat hanger, or a slipper, you should roll up a newspaper, and smack yourself on the head with it for leaving those things out.. your puppy is going to explore things, that’s normal! It is 100% up to YOU to keep those things away from your puppy when your puppy is unsupervised… even for just a moment.

Remember to never scold your puppy for grabbing these things. They are just curious little cuties, and they don’t chew things up to bother us.. Dogs do not have intentional thought, so they aren’t ever doing anything ON PURPOSE to us.. The most important thing you can do when your puppy is chewing something you don’t want her to be chewing is TRADE her the inappropriate item with a toy of hers, so she understands “no honey, that isn’t what puppies chew on… THIS is what puppies chew on!” and then begin playing with her using her toy to show her that TOYS ARE FUN.. Way more fun than a boring ol’ coat hanger.

Another helpful thing you can do is have two bags of toys. In each bag is many different kinds of toys. Lots of chew toys, lots of soft squeaky toys, lots of rope-type toys, a bunch of balls.. All kinds of things! For one week you have bag#1’s toys out for your puppy to play with.. At the end of the one week, you collect those toys, and you bring out bag#2! The toys will be more interesting/feel like new to your puppy, which will in-turn, make her chew less inappropriate things. Her toys are too fun to care about that dumb Wii-mote that you left laying around.

Hope this helps!

Q. My 3 month puppy eats his own poop and is also biting what can I do to prevent this
ANSWER : A. When it comes to poop eating, you want to consider a few things. First off, what is his diet like? Maybe something is lacking in his diet that is causing him to want to eat his own poop. This is the most common reason why dogs eat THEIR OWN poop. Try a higher quality kibble like Taste of the Wild, Ziwipeak, Orijen.. and try feeding three meals per day, instead of the more common two meals per day. Remember to gradually switch his kibble. Add a little bit of the new kibble and reduce the old kibble very slowly.. little by little every couple of days until the bowl is mostly new kibble! You should also be cleaning up his poops IMMEDIATELY after he does them.. I mean like, you have a bag in your hand, and you are low enough to scoop it up RIGHT when he finished so he doesn’t have a chance to eat his poop.

When it comes to nipping there are a few things you can do. First, you should yelp as soon as the teeth touch your skin, stand up, cross your arms, and ignore the puppy until he is ignoring you. Once he is off doing his own thing, swoop down and calmly reward him by playing with him WITH A TOY so he doesn’t nip your hands. Whenever you pet him, or interact with him, you should always have a toy on-hand so you can give it to him. This toy should be a soft braided rope toy that YOU own. This means, your puppy is never allowed to have this toy on the floor, and your pup can never “win” tug games with this toy. This is YOUR toy that disappears when you’re finished playing, and reappears when you want to play. If you keep this up, in a weeks time, your puppy will be so excited to see that toy, that as soon as you bring it out, he stops nipping you because he wants to play with the toy. Another thing you can do is have two bags of toys. Bag#1 is full of chew toys/soft toys/squeaky toys/etc. After one week, Bag#1 disappears and out comes Bag#2. Bag#2 has the same types of toys as Bag#1, and it only stays out for one week. This keeps the toys feeling like new to your pup!

Q. What solid food should I start 4 week old Pit Bull puppies on?
ANSWER : A. A puppy food designed for large breed puppies can help with rapidly growing bones and joints and can be given in a wet form easily to puppies learning to eat solids. You can also provide a dry kibble for them to try and should moisten it with water or some formula to make it easier for the puppies to eat and digest. As the puppies grow and their teeth come in, they will begin to eat and explore more of the solid food on their own.

Mom should also be on a Puppy formula while nursing her puppies as it will provide extra nutrients to both her and babies while they are in a very rapid stage of growth!

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. Why do dogs eat grass?
ANSWER : A. Some pet parents get concerned when they see their favorite canine nibbling on grass in the yard. They wonder whether it is because hunger, boredom or an indication of an underlying illness. Often the consumption of grass will result in vomiting because it irritates the stomach and gastrointestinal tract. This is an extremely common problem for dog parents. There is no one reason for why dogs exhibit these behaviors and it is very much dependent on each dog. Here are some of the reasons why our dogs choose to eat grass:

1. Nutritional Issues

Historically speaking, dogs are considered omnivores, which mean they consume a variety of both meat and plant-based food. There is some indication that dogs with a low fiber diet may choose to scavenge in the grass to fulfill this nutritional deficiency. These dogs may also find that grass has an appealing flavor and consistency. If you feel that this may be the reason for your beloved canine consuming grass then consider discussing with your veterinarian on how to incorporate more fiber into your dog’s diet.

2. Boredom

Many dogs who are not receiving adequate exercise will be become bored and search out activities to occupy their time, including eating grass. Evaluate how much exercise your dog is getting on a daily basis and consider more walks or other fun activities, such as playing fetch or tug of war.

3. Upset Stomach

There is a belief that dogs with an upset or gassy stomach will self-medicate by consuming grass. Vomiting often follows this grass eating activity eliminating the contents of the stomach or changing the gas distension within the gastrointestinal tract. However, there is not much scientific evidence to back up this theory. If you are concerned about too much gastric acid in your dog’s stomach or any other underlying medical issue that could be the reason for their grass eating, consult with your veterinarian.

Overall, grass eating is usually not toxic to your dogs unless your lawn contains chemicals, including pesticides or herbicides. Monitor your dog’s behavior along with his diet and exercise to determine if there is a reason for the inappropriate grass snacking.