A worrisome health trend among dogs and cats across the country has surfaced in the past few months. Scores of pets from California to South Carolina have experienced sudden and recurring bouts of diarrhea, vomiting, and other digestive problems.

Through an examination of reports submitted by readers, ConsumerAffairs.com has uncovered a common link among these pets: They all ate the same brand of food: NUTRO pet food.

In all of the cases we've examined, the animals' conditions improved once their owners switched them to another brand of food.

"I've been feeding my chocolate Lab, Indy, NUTRO for almost four years," said Laura F. of Las Vegas, Nevada. "He's always been happy, healthy, and big. Recently I switched him to NUTRO (Natural Choice) Lite at my vet's request. Three weeks ago, he started vomiting uncontrollably."

Laura said her veterinarian initially thought Indy had pancreatitis, an inflammation of the pancreas. The vet prescribed some medication and Indy's condition gradually improved.

"Now, three weeks later, he started vomiting again," she said, adding she continued to feed her dog NUTRO. "He's now lost about 8 pounds in three weeks and is weak and lethargic.

"The vet believes -- as do I -- that it is the food," she said.

Laura switched brands of dog food and Indy's health improved. After a while, Laura tried mixing in the NUTRO with the new food. But that turned out to be a bad idea.

"The vomiting started again," Laura said. "I also noticed that he only ate about half his food and was actually dropping the NUTRO out and trying to only eat the Science Diet. I think even my dog knows there is something wrong with the NUTRO food.

"I will never feed any of my pets NUTRO again."

Similar stories

We've heard similar stories and sentiment from scores of pet owners nationwide -- many of whom are loyal NUTRO customers. We've also heard from a pet store employee, who noticed these same digestive problems with her clients' pets that ate NUTRO products.

A pet owner in South Carolina told us that she found foreign objects in her last few bags of NUTRO foods.

And a disabled woman in California said all these pets' health problems have given her a horrible sense of dj vu. Her service dog, she said, experienced these same digestive problems a few years ago after eating NUTRO food.

"I would not venture to give any pet one nugget of NUTRO food after what my dog went through," said Maggie D. of San Francisco.

NUTRO responds

NUTRO, however, defended its products.

A spokeswoman told us she is unaware of any substantiated medical problems like these linked to her company's pet food.

Many NUTRO customers also tout the food, saying it's an excellent product. Veterinarians told ConsumerAffairs.com that many factors can cause gastrointestinal problems in dogs and cats, including changes in diet, newly-developed sensitivities to pet food, or viral infections.

But scores of pet owners who've contacted us are convinced that something is now wrong with NUTRO's food.

They're pet owners like Lynn C. of Cabot, Arkansas.

"I've used NUTRO for years and never had any problems," she told us. "But my 10-year-old border collie, Boo, became sick six weeks ago. He was lethargic, lost weight, and when evaluated by a veterinarian, his liver enzymes were critical. They were elevatedoff the chart. My vet said we've got to do something.

"She put him on antibiotics and a strong amino acid, but he continued to deteriorate."

A week into Boo's treatment, a co-worker told Lynn about problems she'd read about regarding NUTRO's pet food.

"I had never dreamed it could be the food," she said. "I'm feeding all four of my dogs the food, so why all of the sudden would it affect Boo? The other three are still thriving. But they're youngerand he's the smallest dog."

Lynn did some digging and found the complaints filed by pet owners on ConsumerAffairs.com.

"I was shocked at the information that I found on NUTRO," she said. "I faxed pages and pages of this information to my veterinarian, who became alarmed and told me to stop feeding him the NUTRO."

Within days, Boo's condition improved.

"He started acting like he felt better," Lynn said. "It's amazing. He wasn't responding until I took him off the NUTRO food. Within a week, he had regained two pounds, and after two weeks, his liver enzymes were still high, but improving.

"I cannot explain why this happened all of the sudden since Boo has been eating this food for years. But I know my dog and I know it was the food."

Another pet owner in the small town of Cabot, Arkansas, who shows Westies, said her dogs experienced the same problems with NUTRO's food.

"I started using NUTRO Natural Choice for my show dogs last fall," said Judy Y., who has fed dogs NUTRO on and off for years. "With the last two bags my dogs started to lose weight and their stools were extremely soft. One litter had constant diarrhea. They were losing weight, their coats were not in the condition they should be. And after they ate, they would suck up water like they hadn't had any all day.

"The only dog I wasn't having problems with was the old dog that can only eat raw meat, no dog food at all."

Judy also noticed that one of her puppies wasn't growing.

"She was growing fine until I put her on NUTRO," Judy said. "And then it was like she just stopped growing. She looked like she had been starved and her coat looked real bad."

Judy's vet examined the dogs -- and their stools -- and didn't find any problems.

"So I said the heck with the commercial dog food and I started feeding all my dogs raw food," Judy said. "They've all bounced back. They have all gained weight and their hair is growing again."

The only exception is the puppy that had growth problems.

"My puppy is 10 months old now and her growth seems to be stunted," Judy said. "I have never had this happen in the 40 years I have been showing and breeding dogs. I'm not sure this show quality puppy will now get big enough to show or breed. It is so heart breaking to see such a good quality dog not live up to her potential because of a dog food."

Similar tales

Scores of other pet owners echo these concerns. Consider some of their pets' recent experiences with NUTRO:

Michele T. of Northridge, California: "I've been feeding my dogs NUTRO Natural Choice Senior kibble for years. Lately, the last few months, they've both had very upset tummies and very unusual and loose stools."

Rachel B. of Indianapolis, Indiana: "I have a three-year-old Poodle who I got from a rescue (group), and he's been on NUTRO Max since I've had him. Within the last few months, he has had quite a few digestive problems that his vet has not been able to figure out thus far. He has not been eating like he normal does and his stools have been incredible sporadic -- soft then hard, then soft then bloody. His appetite has been pretty bad. He'll wait to eat until he's starving because he doesn't want to eat the food. He's drinking water like he's been in the desert, and coughing and dry heaving a lot. He repeatedly tests negative for stomach parasites and we have been uncertain what the problem was until I received an e-mail about NUTRO foods from the shelter he came from. I know I will be weaning him off NUTRO immediately!"

Kelly M. of Moyock, North Carolina: "I switched my dogs to NUTRO Natural Choice Large Breed chicken and rice, thinking I was improving the quality of their food. They loved it! Unfortunately, a few days after I began feeding the new food, which I converted by mixing in increasing quantities over a week long period, both of my dogs -- a Great Dane and a Dane/Blue Tick mix -- developed watery bowels and lots of digestive activity. We took the Dane to the vet, because he exhibited symptoms first, and they performed a fecal test for both parasites and Giardia. Both were negative. When the other dog began having the same symptoms, I began to suspect the food. I placed a call to NUTRO yesterday and spoke to a customer service representative. She said they had never heard of any dogs having problems like the ones I described. And then, the next day, I found your Web site and saw the numerous complaints. I am not pleased."

Lin D. of Fresno, California: "I have three miniature pinschers and it (the NUTRO food) has affected all of them same way diarrhea, throwing up, loose stools or totally water stools. They have eaten this food for four years and never had any problems until this last bag. The thing that was interesting is when I opened the last bag and scooped out the food, it was more grainy than normal. My eight-pound girl, she's a wolf and eats everything, she kind of backed away from the food and I had to coerce her to eat. I have taken my dogs off NUTRO and they are doing fine. I also called NUTRO and spoke to a representative in consumer service. She, too, said she had not heard of any problems with the food. She is blaming the shipping and storing of the food she kind of giggled when she said it. I won't go back to that food. My dogs are much too precious to me and I am extremely fortunate I didn't lose them to a bad bag of food."

Jacki G. of Dornsife, Pennsylvania: "I recently purchased a 40 pound bag of NUTRO Natural Lamb and Rice small bites for my Weimer. We've been very happy until this last bag (dated 10 may 2009,13:38 2 a x 4 j p). Our dogs were throwing up, diarrhea as well as the usual allergy reactions. I figured they had gotten into something they shouldn't have, so I fed them brown rice and boiled ground beef to allow their bellies to settle down. The dogs got better. I resumed feeding NUTRO, with the same results. I figured the bag was somehow tainted with corn (which the Weimer is allergic to), causing the intestinal and other reactions. I purchased another food. Symptoms immediately subsided. I was determined not to waste a 40 pound bag of dog food, so I tried to mix it 50/50 with the good food. Bad Idea! Immediate return of symptoms. I called the company to report my dismay. After a 25 minute wait I spoke to a very uninterested woman, who told be to take the food back to the store for a new bag or a refund. I was shocked there was not more alarm that their food wasn't properly manufactured. I was frustrated and dumbfounded at this lack of customer service. I then Googled to see if there was anything going on with other folks. Wow, am I surprised and a little scared that I tried so long to get my Zippo to eat this food."

Leigh P. of Olmsted Falls, Ohio: "After years on NUTRO, both my cats started vomiting almost daily. I did plenty of research, feeling that I should switch their food. I will never feed commercial brands like this again. My cats are now on a raw BARF diet, which they were designed to eat, and they are thriving and healthy. My Persian cat, who lost fur four years ago from an illness, is now fluffy again after just 1 month on raw. Don't feed NUTRO or commercial brands. Now I feel guilty for donating this poison to my animal shelter."

Pet store employee

These problems don't surprise a pet store employee in California, who contacted us with concerns about NUTRO's products.

"Of the customers that come in with health issues occurring in their pets -- such as those described by the people reporting here (on your Web site), NUTRO is the only food with these problems," said the employee, who asked to remain anonymous for fear of losing her job.

"We've averaged 20 customers a week with this food issue for the last five months or so. I'm rather surprised it's continuing and that nothing is being done about it."

Foreign objects

ConsumerAffairs.com also heard from a South Carolina pet owner, who discovered what she calls "foreign" objects in her recent bags of NUTRO food.

"In two of the last five bags I've fed my dogs, I've found pieces of something that look like nylon," said Lori W. "I found one piece stuck out from one end and hooked through a piece of kibble. It was maybe one-half inch long. Most are a lot thinner."

Unidentified object found in Lori W.'s NUTRO pet food

After making these discoveries, Lori switched her six dogs to another brand of food.

Lori's pets

"I don't know, maybe that's supposed to be in there," she said. "But I'm transitioning my dogs to another food. I'm not panicked, but I got concerned after reading the other comments (on ConsumerAffairs.com). I can't deny that I found something in the food that I've never noticed before."

Lori also said one of her dogs -- an eight-year-old German Shepherd-Great Dane mix -- recently became ill after eating some NUTRO food.

"But that could be totally coincidence," she said. "Rufus has had bouts of soft stools and diarrhea since we've had him. But now I wonder if he had some sensitivity to NUTROafter we opened that last bag of NUTRO, he got sick."

She added: "I loved NUTRO and would love to continue loving it, but I'm just not comfortable with the food right now."

Service dog

She -- and other pet owners -- shouldn't feel safe feeding their dogs and cats NUTRO, warned a disabled pet owner in California.

Radio talk show host Maggie D. said her service dog -- a Pit Bull-mix named Little Maggie -- became ill a few years ago after eating NUTRO food.

"I'd been feeding her NUTRO since she was a pup," said Maggie, who hosts a radio show for people with disabilities on KUSF. "Then she suddenly started having digestive problems. She had terrible diarrhea. She'd indicate that she needed to go out, but couldn't wait. She was also lethargic and she'd drink a lot of water and then quit drinking water.

"She lost a lot of weight. She had absolutely no energy and could not pull my manual wheelchair as trained."

That meant Maggie could not leave her home.

"She's my lifeline," Maggie said of her beloved service dog. "She goes everywhere with me."

Maggie knew she had to act fast. She couldn't function -- physically or emotionally -- without Little Maggie.

She immediately switched Little Maggie from NUTRO to rice and cottage cheese.

"It took about 12 to 14 days of this diet to bring her back to normal stool formation," Maggie said. "I then would slowly re-introduce the NUTRO one nugget at a time -- more each day until she was entirely off the rice/cottage cheese diet."

But Little Maggie's condition worsened again.

"Within a month, she returned to the watery frequent stools," Maggie said. "Back and forth we went between the NUTRO lamb and rice and the rice and cottage cheese until my vet told me to put her on straight boiled chicken breasts and boiled skinned diced potato.

"After three months of the chicken/potato diet she had a shiney coat, her hair was silky once again as is her skin," Maggie added. "She had boundless energy again. She now pulls my wheelchair and stretches herself across the bed so I can pull up to a seated position and get ready to transfer to my wheelchair."

Is Maggie surprised by the recent problems dogs and cats have experienced with NUTRO products?

"No. I think they're using something different in the food they have to add fillers," she said. "I have no confidence in them."

'Look out'

Maggie decided to contact us now -- even though her problems with NUTRO occurred two years ago -- to warn other dog and cat owners about this brand of pet food.

"My message to pet owners is -- look out. If you love your animal get them off NUTRO. I would not trust the pet food industry or commercial pet food. I will never feed my animals NUTRO again."

But many pet owners stand by NUTRO and its products. And they warn consumers not to jump to conclusions based on unsubstantiated claims posted on the Internet.

"I have used NUTRO for both of my dogs and both of my cats for over two years now and I have nothing but wonderful things to say about this product," said Jennifer A. of Spokane, Washington. "The benefits are amazing and the ingredients are quality. I was a little shocked when I read some of these postings, but it will not make me quit feeding this product. I think that people need to remember that animals are like people, just because you get sick, you would not quit eating everything that you had before."

She added: "I have called NUTRO and spoken with them on numerous occasions concerning ingredients and other aspects of their food, and they have always been very nice. I find it extremely unlikely that a business would laugh at a customer on the phone, not only from a sensitivity standpoint, but also from a liability standpoint. Overall, I think NUTRO is a great product. My feeling go out to all of the people that have lost a pet, but unless you have actual proof, it is dangerous to spread false information. Get facts."

A Maryland pet owner agreed.

"We've been feeding NUTRO for years and never had a problem," Tabitha A. of Upper Marlsboro, Maryland, told us.

She advised pet owners to consider the following before criticizing a pet food:

• If you change your dog's food quickly, it's likely to get an upset stomach;

• Things can happen to any food -- people or pets. "It can get damp or bugs or be out of date, and it isn't always the manufacturers' fault."

• Even a careful company can have occasional problems. "If you have problems and can't attribute it to anything but the dog food - contact the company," she said. "They may ask for food to test. If you don't contact them, and there is a problem, they can't fix it or do a recall. I had a friend who got food with an incorrect mix and because she was diligent and sent samples, the company did a recall. She had already stopped feeding her dogs the specific batch, but she probably saved many lives."

A woman in Winnipeg who runs a dog rescue also defended NUTRO and its products.

"You had asked for bad experiences and good, but chances are you likely will not print the good ones," wrote Sally H., who runs Hull's Haven Border Collie Rescue in Winnipeg, Canada.

"All of my own dogs are on NUTRO, as are all of our rescues. We have had excellent results placing emaciated dogs on High Energy, puppies raised on NUTRO Puppy, seniors and overweight dogs on NUTRO, and we have had nothing but good results. Not only do we use the brand ourselves, but we also ask our adopters to continue to use it, as we want the best in health for our rescues," Sally said.

'100% safe'

A spokeswoman for NUTRO told us the company's products are 100 percent safe and meet all standards set by the Food and Drug Administration (FDA) and other federal regulators.

"NUTRO pet foods undergo rigorous quality assurance testing beginning with raw ingredients and ending with testing all finished products," said company spokeswoman Alice Nathanson. "This includes testing to confirm that no melamine, mold toxins, or pathogenic bacteria are detected in any NUTRO pet foods."

Nathanson said her company is aware of the complaints posted on the Internet about NUTRO's food.

"Some things can get posted and they are not verified," she said. "I'm not aware of any issues with the products. My dogs eat NUTRO and they have never had any problems."

Nathanson encouraged worried pet owners to contact the company directly with their concerns.

"We absolutely want to hear from customers," she said. "The safety and quality of our products is our top priority. When a consumer does have a concern with any of our products, an in-depth review of the consumer-provided samples is performed to determine if an issue does exist."

What about the complaints we heard regarding NUTRO's customer service department?

"I'm surprised to hear those comments," Nathanson said. "We take any complaint seriously and we will conduct an in-depth review if a consumer provides us with samples."

The best way to contact NUTRO, she said, is through the company's Web site: www.nutroproducts.com. Pet owners can also call NUTRO at 800-833-5330.

Veterinarians skeptical

Veterinarians we contacted about the recent problems dogs and cats have experienced with NUTRO products told us it's not uncommon for pets to have sudden bouts of gastrointestinal problems.

They also said a number of factors could be the culprit, including pet food.

"Food can cause GI upset if sudden changes are made in the type of food you're feeding," said Dr. Robert Backus, an assistant teaching professor and director of the Nestle-Purina Endowed Small Animal Nutrition Program at the University of Missouri's College of Veterinary Medicine. "And there may be some intolerance if you wean them from a previous food to another one."

He added: "As far as pet food manufacturing goes, I'm not an authority. There are many ingredients that go into these products and there could be problems with an ingredient source. There also could be problems with the formulation. And there are occasional processing problems -- maybe the food was over-processed or under processed -- which could affect GI health and pets could end up with diarrhea."

Dr. Steven Hansen with The American Society for the Prevention of Cruelty to Animals (ASPCA) agreed.

"There could be many causes for what you're seeing," said Hansen, a veterinary toxicologist. "Changes in diet can likely make a change in what's happening to a (pets') system. A dog may have a sensitivity to whatever he's eating even if he's eaten the food for a long time. What can happen is they develop a sensitivity to one ingredient and now their systems no longer manage the food right. That doesn't mean there is something wrong with food.

"Stress could be another factor."

Hansen, however, suspects another culprit is to blame for these recent bouts of GI problems: "A viral infection seems the mostly likely cause to me."

The ASPCA's Poison Control Center, he said, has not received any cases regarding NUTRO's food in the past six months.

"We get hundreds of cases a day and I have zero cases on NUTRO products. But given the symptoms pet owners are reporting -- they're mild gastrointestinal problems -- we might not get calls. So, I'm not aware of these problems, we have no data on them, but I'd like to know more information."

Hansen, for example, wondered if any of the pet owners fed their animals' NUTRO products with the same lot and formulation numbers.

Few pet owners had that information.

"If they have the same lot numbers, it would get my attention," Hansen said. "If they have the same formulation numbers, it may suggest there may be an ingredient that's the problem."

He and Dr. Backus encouraged pet owners whose dogs and cats have experienced these recent GI problems to contact their veterinarians.

"They need to document the problems -- especially if they are serious problems," Backus said. "And bloody diarrhea is a serious problem.

"I would also recommend that if they suspect the food is the problem, they should take a freezer bag full of it -- along with the label information that has the product's name and lot numbers -- to their vet," he added. "If the vet suspects the food is the cause, the vet should then contact the company and FDA. If there's a problem, we need to document it and get supporting lab results."

Dr. Hansen also recommended that Lori S. -- who found "foreign" objects in recent bags of NUTRO -- send samples of that food directly to the company.

"NUTRO can do a microscopic examination of the food," he said. "Maybe it is something that is normal. But if it's not, NUTRO should tell her what it is. In light of the (2007) pet food recall, I would expect pet food manufacturers to be responsive and give her an explanation for what it is."

Waiting for results

Some pet owners told us they've already sent in samples of their pet's food to NUTRO. They're now waiting for the results.

Others said they've reported their concerns to the FDA.

A few pet owners told us they hope this is all just a bad coincidence or a couple bad batches of food. Most pet owners, however, are grateful they learned about others pet' experiences with NUTRO.

"I cannot believe that a company that sells their product as safe and natural is instead injuring and killing pets," said Lynn of Arkansas. "If I had not been informed about other pet owners' experiences with NUTRO Natural Choice, my dog would be dead I would have kept feeding him the food.

"It is my hope that some consumer group or authority will begin to investigate this company and its products before other pets are affected."

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