Mary Allen
Take precautions in good time!
Cats – this applies to our domestic cats as well as to wild cats, tigers, and lions – as obligatory carnivores, they have to process a high proportion of dietary protein. Most of the protein contained in meat goes into the energy balance. The nitrogen contained in this protein has to be converted into urea in the liver and excreted through the kidneys. This means that the metabolic load on a cat’s kidney is 2 – 3 times higher than that of a herbivorous kidney. Accordingly, the wear is also higher.
In healthy mammals, the kidney consists of a few million nephrons. They consist of the filter unit, the glomerulus, and the urinary tubule, which opens into the collecting duct and ends in the renal pelvis. Urine production occurs in two stages: First, almost all of the liquid in the glomerulus is squeezed out of the blood. The primary urine filtered in this way is thickened again in the urinary canaliculi. 80-99% of the water is recovered, individual metabolic toxins are actively or passively excreted in the primary urine, and other substances are transported back into the vascular system with the water. At the end of the excretion process is the secondary urine, which is collected in the bladder and finally excreted. If the body has a lot of liquid after drinking a lot of water, then water is also excreted in large quantities. The urine is then clear and hardly smells. If the body lacks water, it can produce very concentrated, dark yellow urine.
Kidney failure is only noticed when more than 90% of the nephrons are impaired in their function. First of all, the body increases the activity of the remaining filter units to such an extent that the excretion is still carried out normally. However, this increase in work output puts undue stress on the nephrons; as a result, they wear out faster. A spiral is set in motion that is becoming increasingly difficult to stop.
In the case of kidney failure, the primary urine fails to concentrate: the animal produces more and more urine, and the owner does not think of kidney failure at all because he observes that the litter box is used well. The cat increasingly loses fluids and becomes dehydrated. This results in the first symptoms of illness that lead the owner to the vet: excessive thirst, dull and dried-out shaggy coat, or fishy bad breath with or without vomiting.
In this state, which is usually no longer reversible, about 95% of the nephrons have already failed. Therefore, early detection is of great importance: Cats over 8 years of age should have a blood or urine test every year. This means that the impairment of kidney function can be detected at an early stage. If treatment with medicines and kidney protection food starts in good time, life expectancy can be extended by years – to the benefit of humans and animals!