Experienced and professional animal trainer provide their insights in answering this question :
A. Is he vomiting or lethargic? Food should always be introduced slowly over 7-10 days as that can cause diarrhea, if there are any other symptoms then contact you vet. Try introducing 3/4 of old food with 1/4 of new food for a few days & then half & half for a few days followed by 3/4 of new food with 1/4 old food for a few days before completely changing onto new diet.

How to Identify Common Pet Problems ?

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Bland, stomach-soothing foods like boiled chicken, rice, and pureed pumpkin can temporarily help your pup manage symptoms while keeping something in their tummies. However, always be sure to consult your veterinarian before introducing a new food into your puppy`s diet.
Switching your dog`s food abruptly can cause gastrointestinal upset such as vomiting, diarrhea, and a decreased appetite. Any time you decide to change your dog`s food, you should transition to the new diet gradually in order to give your dog`s system time to adjust to the change.
Diarrhea is not uncommon when it comes to puppies and can be caused by the stress of a new situation, viruses, parasites, or changes in diet or lifestyle. Mild cases can likely be treated at home, but more severe cases of puppy diarrhea can be a serious problem.
A bland diet for 24 to 48 hours may help to resolve your pup`s issue. Plain-cooked white rice with a little chicken and some canned plain pumpkin (not pumpkin pie filling) may help to make your pup`s tummy feel better. Once your pooch feels better, gradually reintroduce their regular food.
Diarrhea in dogs can occur suddenly and last as long as a day or two up to a few weeks or months. If your dog`s diarrhea persists for more than a day, dehydration can be a concern. Diarrhea that lasts longer can be an indication that your dog has an underlying health issue.
Puppy diarrhoea can be caused by stress, a new diet, viruses, bacterial infections, parasites, food intolerances, poisons, toxins or from eating things they shouldn`t. Understanding the likely cause can help you decide if you should manage their diarrhoea at home or contact your vet for advice.
Most pet`s suffering from diarrhoea due to a change in food will recover within 1-3 days.
Young puppies are prone to parasites. Whether they are born with parasites or pick them up from the environment, parasites like roundworms, hookworms, whipworms, coccidia, and giardia all cause diarrhea in puppies and all require veterinary attention.
If diarrhea continues for more than a day or two, schedule an appointment with your veterinarian to help your dog get some relief.
The good news is that, in most mild cases of puppy diarrhea, it will pass on its own. However, it`s important to seek advice from your veterinarian to confirm the underlying cause and rule out any serious health issues, especially if diarrhea persists for more than a day or two.
Diarrhea can lead to dehydration, so make sure to give your dog access to water at all times. You may also offer unflavored Pedialyte to help maintain electrolyte balance under a vet`s advice.
My dog has diarrhea, What should I do? Fast your dog for 24 hours. Only water is permitted. After the 24 hour fast, begin feeding a combination of boiled white meat chicken (with all the skin and fat removed and the water poured off) and boiled long grain white rice.
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.
With diarrhea, the stools become loose and watery instead of solid. If you have diarrhea, there`s a good chance you picked up a stomach virus. Or, you may have gotten food poisoning from eating food or drinking water that was contaminated with bacteria.
If your dog has severe bloody diarrhea or is showing more generalized signs of illness such as weakness, fever, vomiting, abdominal pain, loss of appetite, or dehydration, the cause may be more serious and medical attention should be sought as soon as possible.
Usually most diarrhea will run its course within two to four days, although in some cases, it can last longer. If there are any other signs of illness like vomiting, loss of appetite, depression, or pain, a veterinary trip is in order.
Most mild cases of gastroenteritis improve within one to two days, but if your dog has been vomiting or passing a lot of diarrhoea they may become poorly through dehydration. You know your dog best.
Fasting is usually one of the most common interventions for the runs. It usually lasts between 12 and 24 hours, with a small but frequent amount of water given to your pooch. This may change depending on the size, age, and overall health of your dog.
Far and away the most common cause of diarrhoea in dogs is wheat gluten (most dry food, dog treats, bread, pasta, biscuits, etc). But there are a number of other causes too. If your dog is suffering recurring diarrhoea then it`s likely you`re making some simple mistakes diet-wise. The first he`s likely to be dry fed.
Contact your vet right away if your pup is experiencing repeated episodes of diarrhea or chronic diarrhea. If your dog is showing other symptoms as well as diarrhea they should be seen by a vet as soon as possible.
If your dog has diarrhea for more than 24 hours, if there is blood in the stool, or if your dog is lethargic or also vomiting, it is time to take them to the veterinarian. Be sure to provide easily accessed, fresh water so your pet does not become dehydrated.
Most cases of dog diarrhea are self-limiting and will resolve on their own in a day or two. Many dogs with diarrhea act and feel fine so there`s no need to worry in most cases. Stopping diarrhea is usually as simple as fasting your dog and returning to a bland diet.
1) Overfeeding – Many owners are unaware that overfeeding can cause loose stools. This is due to an `overload` of the digestive system, meaning it is unable to absorb what it needs and instead expelling it. This is more common in young puppies with sensitive stomachs but can happen at any age.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. My 3 month old puppy has had diarrhea, liquid form. This is the second day. What should I do? I recently changed his food as well.
ANSWER : A. Is he vomiting or lethargic? Food should always be introduced slowly over 7-10 days as that can cause diarrhea, if there are any other symptoms then contact you vet. Try introducing 3/4 of old food with 1/4 of new food for a few days & then half & half for a few days followed by 3/4 of new food with 1/4 old food for a few days before completely changing onto new diet.

Q. I currently feed my 2 year 31 lb Beagle 1 1/2 cups of Eukanuba a day. I was thinking of changing his food, can you recommend something?
ANSWER : A. If you are looking for a higher end food to feed your Beagle, there are many available now in commercial pet stores. Many brands such as Blue Buffalo, Nutro Natural Choice and others offer holistic foods that tend to be more meat based than carbohydrate based. Some brands such as Royal Canin also offer foods that are specific to certain breeds. This means the products tend to have more digestible ingredients in them rather than fillers. They may also avoid some allergenic ingredients such as corn, wheat and soy products which can cause digestive issues in some dogs. However, Eukanuba, Science Diet and others are a good mid-grade brand and many dogs do very well on it.

If you do decide to switch your dog’s food, it should be done so gradually to avoid digestive upset. A routine of 9 days is best for switching over. This involves 3 days of 25% new/75% old, 3 days of 50/50 and 3 days of 25%old/75% new before finally feeding only the new food. Also be advised that depending on the ingredient changes, foods that have different grains or fewer grains in them may slightly change the consistency and size of your dog’s stool.

Q. I’m fostering some now motherless 5 week old Pitbull puppies. There are 5 of them. How much do I feed them? I give them blue buffalo puppy food by wa
ANSWER : A. It should say on the Blue Buffalo on the back under, “puppies” or some sort of age chart. Make sure it’s puppy food.. puppies need extra protein and nutrients. http://bluebuffalo.com/product-finder/dog/?facets=Puppy,Dog_DryFood#

http://www.bullytree.com/wp-content/uploads/2013/08/Feeding-Chart-Blue-Buffalo.gif – On the back of a puppy-food bag from Blue Buffalo it says underneath 3-5 months, “3 to 20 lbs: feed 1/3 – 1 1/4 cups per day” and “21 to 50 lbs: feed 1 1/2 – 3 cups per day.” Make sure you are breaking that up into at least three meals. Let’s say you decide to feed them 1 1/2 cups per day each, then, you should measure that out, and set it aside. Throughout the day, you should offer at least three mealtimes with that set-aside amount. You want to start with the least amount, and then if they seem hungry (licking the floors, begging you constantly for food, whining/crying) feed them a little more until you get it right. Do not overfeed, and try to avoid underfeeding a well.

Q. Changed dog’s food. Now throwing up and with diarrhea, what should I do?
ANSWER : A. Vomiting and diarrhea can occur if food is switched too quickly. Dogs generally need a slow changeover of foods over a period of a week or so to allow their guts and the gut bacteria to adjust. If there has only been one vomiting and diarrhea episode, removing the food for a few hours then feeding a bland diet of boiled chicken and plain rice can help soothe the stomach. You should then return to his old food and begin a gradual changeover of foods starting with 3 days of 75 old/25 new, 3 days of 50/50 and then 3 days of 25old/75 new. However if the vomiting and diarrhea symptoms do not improve, it may indicate something else causing his digestive distress and an appointment should be made with your local vet.

Q. 13 yo Dalmatian, suffers from colitis and arthritis. Vet recommended Chappie, and gave her all her life. Should we change it considering her problems?
ANSWER : A. Chappie was the original name of the product that is now known as Pedigree. Pedigree is considered a “grocery” style food, meaning it may not be as high quality or include higher quality ingredients as other products. However, the Pedigree line has expanded quite a bit in recent years and now offers many products tailored to dogs of all ages, sizes and breeds.

If your dog has done well on the product, you may be able to just switch over to a variety that is geared more to your dog’s needs such as a large breed senior formulation. Senior formulations often have added supplements to help with joint pain and arthritis later in life. However, if your dog has been experiencing problems with the food product, switching to a higher quality food such as one without grains may help. Higher quality foods will often have alternate grain sources to prevent digestive upset as well as higher quality meat cuts listed on the top of the ingredient list.

if you do decide to switch foods, the process should be done gradually over 7-9 days. For the first 2-3 days 25% new/ 75% old should be given, then 3 days of 50/50, and 2-3 days of 75% new / 25% old before finally switching over. This will help minimize any stomach upset from changing to a different food too quickly and allow the intestinal bacteria to adjust.

Read Full Q/A … : Best Low Fat Dog Foods

Q. I have 3 shihtzus 2 have diarrhea seem fine otherwise I did change there diets in the last 3 days for all. They eat imams canned food twice daily now
ANSWER : A. Some dogs have more sensitive stomachs than others so a change in diet may have been enough to cause it. Did you introduce the new food gradually? We normally recommend doing it over 7-10 days (a quarter of new food with 3quarters of the old food for a few days, then half and half for a few days etc). Was there a reason for changing their diet? If they were fine on the original food then stick to that. If the diarrhea doesn’t clear up in a few days then get some pro biotic paste from your vet.

Read Full Q/A … : Kibbles 'n Bits Dog Food

Q. My cat will not eat the renal food my veterinarian recommended, can I feed a grocery store food?
ANSWER : A. Your veterinarian recommended a therapeutic kidney diet because it has ingredients that will help slow the progression of your cat’s conditions, especially phosphorus and lower protein levels. Many of the non-prescription or grocery store foods generally have high levels of phosphorus and would not be ideal for your cat.

To help your cat accept the new food It is important to do a transition. There are two reasons to do a transition:

1) Occasionally a pet will have a GI upset when switched to a new diet,

2) A pet will accept a new food better when a transition is done to allow the pet to get use to the new texture and flavor.

There is more of a chance with a hydrolyzed protein or different (high or low) fiber level food to cause a GI upset. Transition recommendation:

1) Recommend ¾ old diet – ¼ new diet

2) Do this for a few days; if no GI upset, go to the next step

3) ½ old diet – ½ new diet

4) Do this for a few days; if no GI upset, go to the next step

5) ¼ old diet – ¾ new diet

6) Do this for a few days; if no GI upset, go to the next step

7) End with 100% of the new food.

Sometimes a transition should be longer, especially for cats. Use the same recommendation, but instead of a few days, recommend doing each step for a week or more. If you cat is still not interested in the new diet you can research other non-prescription diets focusing on the labels for appropriate levels of phosphorus and protein.

Also, home cooking may be an option but make sure to provide adequate nutrients. A good website to consult is balanceit.com. This website helps you to create well balanced home cooked recipes and offers supplements to add into the diet.

Q. I switched my 3 mo. old Yorkie to Nutro Natural Choice for puppies. Web reviews say dogs have died from it, is it true? Do I switch? If so, to what?
ANSWER : A. I do not personally know of any dogs having a reaction to Nutro Natural Choice products as these products are all holistic and usually made of high-quality ingredients. However, dogs can have an allergic reaction to almost any ingredient (just like people) so it is possible that some dogs may have been allergic to or reacted poorly to an ingredient within the food due to an underlying condition. If you are currently feeding Nutro and your dog is doing well, she may be just fine on it. However if you are concerned, a puppy wellness check up to look for any allergies or underlying issues can always help.

If you do decide to switch foods to another product, there are many products similar to Nutro on the market. Blue Buffalo is the closest choice as far as ingredient content, however many foods are available on the market. Higher end foods often tend to avoid grains that can cause allergies such as wheat, corn and soy products, and may be grain free or mostly meat-based. Some companies, such as Royal Canin will also offer breed specific foods and may have one just for Yorkshire Terriers. If you do switch, be sure to do so gradually over a period of a week to 9 days, slowly adding in more new food and less of the old. This will help prevent any stomach upset from a new food.