Life’s hard

When you’re a fat dog

Part of a new campaign for Chilean lo-cal dog food. It may be amusing but the scene is not presented accurately. Not only are the happy couple doing it missionary instead of doggy style, in my experience canine voyeurs typically react more like drunken frat boys than forlorn, pensive cuckolds.

She’s Not a Reptile

Despite her penchant for basking in the sun I’ve discovered that Zip isn’t a reptile after all.

 EurekAlert reports:

Keeping warm isn’t the only reason lizards and other cold-blooded critters bask in the sun. According to a study published in the May/June issue of Physiological and Biochemical Zoology, chameleons alter their sunbathing behavior based on their need for vitamin D.

“It’s a longstanding assumption that thermoregulation is the only reason that lizards bask,” says Kristopher Karsten, a biologist at Texas Christian University who led the study. “Our results suggest that in addition to thermoregulation, vitamin D regulation appears to have a significant impact on basking behavior as well.”

Chameleons, like humans and most other vertebrates, get vitamin D in two ways: They can absorb it from food, and they can produce it in their skin. In order to produce vitamin D, however, the skin must be exposed to UV radiation.

But – unlike most of her vertebrate cousins Mrs. Zippy can’t synthesize vitamin D3 by basking in the sun.  Like all dogs and cats Zip has to get her vitamin D from eating meat, fish, egg yolks or additives in commercial pet food.

Vitamin D isn’t a single chemical, it’s a group of compounds that can be synthesized in most animals’ bodies from a parent compound  that’s structurally similar to cholesterol.  In fact – today many scientists recognize the biologically active form of vitamin D as a type of steroid hormone (a seco-steriod) rather than a vitamin.

Pro-vitamin D3 or 7-dehydrocholesterol is produced in relatively large quantities in the skin of vertebrate animals like humans, sheep, cattle, horses and poultry.  When the skin of these animals is exposed to sunlight, the 7-dehydrocholesterol in their epidermal and dermal cells absorbs ultraviolet B (UVB) radiation and a series of chemical changes resulting in the formation of pre-vitamin D3 are triggered.  Pre-vitamin D3 is thermodynamically unstable and  it spontaneously breaks down into the far more thermodynamically stable vitamin D3 structure.  Vitamin D3 is a prohormone, not nutritionally important on its own. It has to be metabolized into other active forms in the liver and kidneys.  Thirty-seven forms of Vitamin D3 have been isolated and characterized.

Unlike humans and chameleons, the skin of dogs and cats doesn’t produce significant quantities of pre-vitamin D3 when it’s exposed to UVB radiation.  Their skin contains much lower concentrations of 7-dehydrocholesterol than the skins of species that can synthesize vitamin D so they need to fultill their need for vitamin D3 nutritionally, not through thermoisomerisation.

Some researchers have hypothesized that carnivores like dogs and cats evolved without the need to produce their own vitamin D because the fat, liver and blood of their prey fulfilled their needs adequately.  Vitamin D is also present in commercial dog foods, fish, egg yolks and fortified dairy products – so even if they don’t eat raw fat, liver and blood; most modern dogs still get plenty of vitamin D in their diet.  And because the dietary forms of vitamin D are very stable, fat soluble and easily stored in the body, deficiencies typically only develop when an animal either eats an extremely restricted diet or has a metabolic disorder.

Vitamin D was classified as a vitamin in a somewhat ironic turn of history. In 1920 Sir Edward Mellanby conducted research on rickets using dogs.  Mellanby fed the dogs a diet consisting only of oat porridge (the staple food of his Scottish homeland at the time).  The dogs developed rickets while on the oats-only diet and Mellanby was able to cure them by adding cod-liver oil to their diet.  He assumed that the substance that cured the dogs of rickets was a vital nutritional compound present in the cod-liver oil and he referred to it as “vitamin D”.

Scientists later discovered that vitamin D can be consumed in the diet or produced naturally by our skin when it’s exposed to sunlight.  Though Mellanby’s dogs were raised in an indoor laboratory away from sunlight, we now know that this wasn’t a significant factor in his research. Mellanby’s findings were somewhat  ironic because – unlike other vitamins – vitamin D can be synthesized in the bodies of most animals and because the species he selected for his research was one of only a few species that isn’t able to synthesize the vitamin D on its own.

So, unlike a chameleon, Zip doesn’t bask to generate vitamin D.  She’s just an Australian sun goddess.

Not so Tasty Bytes

H/T to YesBicuit for leading us to this story for our “Oh Crap!” files about a quail believed to be extinct — that was recently photographed for the first time before being sold as food.  Oops…

Australia’s Heraldreports on cats paralyzed by leukoencephalomyelopathy after eating irradiated food.  Orijen cat food is sold in several other countries, none of which have reported problems with the nerve syndrome associated with the food. In an odd bit of circumstance, none of these countries irradiate imported cat food either.  According to the Herald:

The Government insists on irradiating the pet food at much higher levels than human food imports on the grounds that radiation will kill germs and protect Australia from foreign diseases.

Independent tests on the irradiated food have found “substantial reductions in vitamin A levels” and increased “production of oxidative by-products”.

While the pet food company and the Government argue over the precise cause of the illness, cat owners are complaining that nobody will take responsibility.

Hamilton veterinary surgeon Chris McClelland said more than 60 cats had been affected in Australia by the strange nerve syndrome.

Several had died, but others had recovered, he said.

Australian dogs have not been adversely affected by irradiated Orijen food according to the article.

Consumer Affairsreports that yet more pet foods and treats have been added to the PCA peanut recall list.  These were mostly various formulations of American Health Kennels Bark Bars, Cookie Bars and Peanut Butter Crunch.

The company at the heart of this outbreak — the Peanut Corporation of America (PCA) — recently filed for Chapter 7 bankruptcy protection. That action came within days after the company’s president, Stewart Parnell, refused to answer questions about the salmonella outbreak from the House Energy and Commerce investigations subcommittee.

The bankruptcy action also came on the heels of state and federal inspections of the company’s facilities in Georgia and Texas, which revealed PCA shipped products it knew had tested positive for salmonella.

The reports also revealed such unsanitary conditions at PCA’s facilities as dead rodents, roaches, mold, and bird feathers and rodent excrement in a crawl space above the production area at one of the company’s plants.

Sigh.  We’ve got an entire case of peanut butter dog treats that will continue to sit in a closet until I either summon the courage to toss them out or hear definitively that they are not affected by the recall.

In other pet food news the Minneapolis Star-Tribune reports that animal rendering plants are preparing to comply with a new FDA rule aimed at preventing mad cow disease from reaching the food supply. The rule, which takes effect in April, requires that livestock  producers clearly mark cattle 30 months of age or older before sending them for slaughter or rendering (infectious BSE prions are most likely to be found in cattle 30 months of age or older.)

Prion diseases like BSE have not been documented in dogs, but the rule will affect pet food production as rendered protein meals such as meat and bone meal, poultry by-product meal, and fish meal are used in many pet foods.

How much of these products are incorporated into pet foods? Well, according to a detailed report availabe on the National Rendering Association website, specific information on the amount of rendered animals products used to manufacture pet foods is not available.  But the group estimates that about 25 percent of the total U.S. production of rendered animals materials (or about 2.4 million tons per year) is incorporated into pet foods. The new rules may therefore help prevent potentially BSE-contaminated materials from entering a significant portion of the pet food (and livestock food) stream. It will also make rendered ingredients more expensive, and therefore somewhat less desireable.

Another Nutty Recall

Just when we thought it might be safe to pick up some of those convenient potentially toxic processed foods from the grocery store — another massive food recall slaps us back to our senses.  Today MSNBC reported that:

The company that sells Little Debbie snacks announced a recall Sunday of peanut butter crackers because of a potential link to a deadly salmonella outbreak.

The voluntary recall came one day after the government advised consumers to avoid eating cookies, cakes, ice cream and other foods with peanut butter until health officials learn more about the contamination.

Little Debbie, Little Debbie!  It’s not bad enough your snacks are just empty vegan calories sold in non-recyclable waxed cardboard containers – now we hear that they’re unhygenic too.   The tainted foods were made with peanut products produced at a Blakely, Georgia facility owned by the Peanut Corporation of America.  MSNBC reports:

The Scene of the Crime

Most peanut butter sold in jars at supermarkets appears to be safe, said Stephen Sundlof, head of the Food and Drug Administration’s food safety center.

“We urge consumers to postpone eating any products that may contain peanut butter until additional information becomes available,” Sundlof told reporters in a conference call. “As of now, there is no indication that the major national name-brand jars of peanut butter sold in retails stores are linked to the recall.”

“This is an excellent illustration of an ingredient-driven outbreak,” said Dr. Robert Tauxe, who oversees foodborne illness investigations for the Centers for Disease Control and Prevention.

Like other food-borne problems we’ve seen in the last few years, this one may be more widespread than early reports indicate.  According to The Examiner; “potentially contaminated product is showing up in states where it is, supposedly, not distributed.”  The FDA has published an FAQ page on the outbreak in which they state:

FDA and CDC are working to identify foods that contain the peanut butter under investigation. Both agencies will keep the public informed of their progress.

Given their track record on such things, it might be prudent to avoid all peanut butter products for a while.  That includes pet foods, as many dog treats are made with peanut butter.  But because his digestive system operates quite differently than yours; unless your dog is very old, very young or has a compromised immune system; salmonella contamination in dog treats probably presents a greater risk to your health than his.

Pet Food, Pork and Tampons

This just in from Pig Progress:

Australia’s first case of toxic shock syndrome caused by a pig carcass has been officially reported although doctors investigating the case believe there may have been three more human infections elsewhere in Australia.

The pet-food worker, a 41 year old man, developed the human form of the deadly pig disease, caused by Streptococcus suis, while processing animals at a Melbourne plant.

The disease has killed meat workers in Asia, most recently in China, where 215 butchers and processors were infected in 2005, half proving fatal.

In an interview the supervising specialist Dr Adrian Tramontana said, “Initially we believed our patient was the first human case of Streptococcus suis toxic shock syndrome in Australia, but we have since been informed of at least three possible human cases in other parts of Australia.”

According to information provided by Kansas State University:

Streptococci are a family of gram-positive bacteria some of which can cause either localized or systemic infections in both humans and animals. Some strains rarely cause disease and are often considered to be commensal (normal) inhabitants of the skin and mucosal surfaces (oral, nasal, intestinal), while other strains are capable of causing serious or even life-threatening infections.

In dogs, Streptococci (Strep) are known for their ability to occasionally cause septicemia (blood born infections) in puppies and a range of localized diseases in adults. 

In the early 90’s, Streptococci (Group A, ß-hemolytic Strep) emerged as the cause of a previously unrecognized disease in humans. The clinical disease became known as Streptococcal Toxic Shock Syndrome (STSS) because it closely mimics the better known “Toxic Shock” in women caused by toxin producing strains of Staphylococci  (Staph). Rapid onset, high fever, hypotension, and shock are prominent characteristics of STSS in humans.

 Streptococcal bacteria also cause ‘flesh eating’ disease in humans.  And both the toxic shock and felsh eating forms of the disease advance very rapidly.  According to Dr. Brad Fenwick, professor of veterinary medicine at Kansas State University, dogs that develop canine streptococcal toxic shock are healthy only hours prior to becoming very sick.  Without prompt therapy, the dog’s condition deteriorates rapidly with death occurring in as few as eight to 12 hours.  And without treatment, 50% of all infected dogs will die.

Considering the case of the Australian pet food processor — do we need to investigate whether pet food is one source of this virulent disease (it has generally been considered an issue of dog-dog transmission)? 

Our friends over at Pet Connection tell us that the FDA will hold a public meeting tomorrow (Tuesday May 13, 2008 ) in Gaithersburg, Maryland, to discuss pet food safety standards.  Given the problems we’ve seen over the last year with melamine-contaminated wheat gluten, salmonella and other nastiness in commercial pet foods — is it too much to ask that the government require that manufacturer list the name and location of the facility that the food was processed in on the package?

As the FDA moves ahead with tomorrow’s meeting, perhaps we should keep in mind that ironic motto for Rely, the infamous tampon that caused toxic shock syndrome in women, “Rely, it even absorbs the worry!” 

Actually, if you look at the way that parent company, Proctor and Gamble, handled the Rely debacle, it appears that when dealing with last year’s problems, pet food processors followed their example in many ways.  Let’s hope that tomorrow the FDA puts consumer protection before corporate profits — and that pet owners don’t have to absorb the worry.