Sunday, June 3, 2012

I Have A Cat

My cat is diabetic.  When he was diagnosed, the vet said that grocery-store pet food is almost certain to cause diabetes.  Let us examine the reasoning.
Dogs and cats evolved as carnivores, and as such have metabolisms adapted to a high-protein diet in support of a fairly active lifestyle.  When kept as pets they are granted access to essentially unlimited amounts of food that takes little or no effort to obtain.  And their activity is restricted by being confined indoors or in a small yard.

Protein is generally expensive, so pet food manufacturers tend to add fillers in the form of carbohydrates. This led my vet to refer to these products as 'diabetes in a bag'.

In order for the pet food manufacturer to stay in business, customers need to buy their products.  Therefore anything that might trigger a pet's natural finickiness is carefully suppressed.  And flavor enhancers, salt and other substances are added.  As far as the manufacturer is concerned, the pet must keep eating this brand at all costs.

It is also necessary for the pet owner to be satisfied with the apparent quality of the food. He expects nothing less than absolute consistency year after year.

It is also bad form for the pet food to have bugs in it. It used to be that finding the occasional weevil or beetle in a bag of dry pet food was more-or-less expected.
It has been years since I saw any bugs in the pet food.  And if I spill some on the floor in the garage?  Still no bugs.  Hmmmm. Could it be that there are insecticides in the pet food? No labeling requirements. Ignorance is bliss.

All of this actually works.  The life expectancy of a pet is perhaps twice as long as the same animal in the wild. In the wild, death is usually from exposure or predation.  Pets die of organ failure and tumors.  Overall, this is probably a good deal.

And pet food is readily available, reasonably priced, and generally safe in the short term.

* * *


To manage my cat's glucose levels, my vet recommended Purina Veterinary Diets DM Dietic Management Feline Formula cat food.  This stuff is cat food with less carbohydrate content.  It is also _prescription_ cat food.  It is just food with added things (that were not necessary in the first place) left out, but it is still _only_ available by prescription.

And it costs $5.00 per pound.  My cats eat better than I do.

* * *

My cat requires insulin injections.  He weighs fourteen pounds and only requires two units of insulin twice a day.  Feline insulin is only 40% as potent as human insulin because smaller quantities are needed and the dose needs to be a certain size to measure accurately with a syringe.

Therefore, syringes with different markings are used for 40U insulin than the ones used for 100U human insulin.  Naturally, these less-common 40U syringes are more expensive.

One can measure any desired _actual_ amount with either syringe.  You just have to be able to do the simple math to convert the proportions. Even mentioning the use of an alternate syringe to a Health Care Professional is likely to cause an apoplectic attack. There is "the right way to do it" and that is the only way to do it. Because that is what the instructor said in Doctoring 101, and because if you give any other answer on the Standardized Certification Exam you are likely to risk your license.

The Prozinc feline insulin is actually a suspension of human insulin and additives that are designed to make it more effective in the feline metabolism. It comes in bottles containing 400 units.  This means that one bottle will last me about 100 days.

In general, insulin will last up to 30 days without refrigeration, but much longer if kept properly chilled (never frozen).  OK. If I am careful, I can get full use out of the bottle.

The insulin suspension will separate fairly quickly when stored.  It is imperative that it be properly, gently mixed before withdrawing each dose. Even an occasional lapse here will result in an overdose or under-dose in the rest of the bottle that will mess things up badly over the course of the three-month life of the particular bottle.

The insulin bottle has a rubber stopper that is penetrated by the syringe to withdraw a dose. A syringe will be inserted and removed through this stopper 200 times. This is a lot of wear on the single stopper. Even if one is careful to keep the surface clean, over time there is no telling what foreign material gets pushed into the bottle along with the needle.

Each time a dose is removed a comparable quantity of air must be injected into the bottle. This is accomplished by pulling the syringe plunger back in the air, sticking the needle into the bottle, injecting all the air from the syringe into the bottle and then withdrawing the proper dose of insulin.

This process takes whatever is in the air (pollen, mold spores, dust, etc.) and injects it into a previously sterile media. And is repeated at measured intervals two hundred times.

Yet another reason to keep the bottle carefully refrigerated. And my fingers crossed.

* * *

I have alluded to several problems that could be solved if proper attention were given to the entire process.

1. Insulin is one of the simplest proteins and should be very easy to synthesize.

2. There should be a clean and easy way to measure the concentration of proteins in solution.

3. There should be a simple method of detecting foreign material in a solution.

4. There should be a realistic way of creating pet food to a specific recipe, in quantities and at a cost that makes small-scale, local production possible.

5. The regulatory environment that allows pet food to be available 'by prescription only' is another egregious example of abuse of intellectual property rights.