FUS, or Feline Urological Syndrome refers to problems associated with the cat's bladder and urethra in particular.The urethra is the tube carrying urine from the bladder to the outside. This problem is primarily seen in neutered males and cats with an alkaline urine. This has arisen with the advent of the commercial cat foods containing less animal products and more plant products. The normal carnivores' diet produces an acid urine and the wild and ancestral cats were not neutered.These problems usually involve cystitis and/or bladder stones and/or urethral plugs. Cystitis is inflammation of the walls of the bladder and stones are accumulations of mineral crystals. The most common crystals are those of magnesium ammonium phosphate, known as sturvite. Others might be calcium oxalate crystals. Signs often seen will be no urination, difficulty or pain in passing urine, increased frequency of urination and discoloured urine. The condition is most commonly seen in the neutered male, but can occur in the female and intact male.
Any or all of these signs are cause for concern and a trip to the veterinarian for a diagnosis is called for. We shall limit our discussion to bladder stones.
The accumulations of the mineral crystals into bladder stones, or uroliths, may form in the bladder as a result of certain minerals crystallizing around a tiny piece of inner wall that has broken off. The pH, or acidity of the urine, the amount of offending mineral content present in the diet and/or water and the general health of the cat will determine if these stones will form and become large enough to cause trouble. An alkaline or less acidic urine is thought to be a contributing factor from a cereal or vegetable type diet. Cats on high meat diets have acidic urine.
Neutered males tend to have the most problems which I believe is due to the penis remaining smaller than in an intact male.
Therefore, I believe it is better to neuter a male cat after he has reached his adult stature rather than too young. If he is neutered at too young an age the penis and urethra remain infantile combined with the lack of testosterone, the male hormone. The smaller urethra then is more prone to blockage. Older cats of both sexes can develop uroliths as well. If the uroliths become too large they cannot be passed and will continue to grow in the bladder or become lodged in the urethra. Large uroliths have to be removed surgically.
Prevention involves having males neutered after they have reached the adult size and avoiding water and foods with high mineral (ash) contents. Some rural water supplies for drinking and crop production contain high levels of the offending minerals that can lead to these problem.
Poor quality dry cat foods, which contain low amounts of animal products and large amounts of plant products, fed over extended lengths of time, may also contribute to this problem as the urine becomes less acidic. A lack of sufficient good quality drinking water may contribute with the cat not drinking enough to flush out any offending crystals and the water may in fact be high in minerals prone to crystallization.
Acidifying the urine also helps. Ascorbic acid or vitamin C supplementation and low ash diets are in order.
The best prevention is to neuter our males after they reach adult stature, feed good quality cat food with adequate animal products and provide fresh good quality drinking water.
If we should suspect a urinary problem, a visit to the veterinarian should be quickly planned so that the problem can be identified and attended to as quickly as possible. If complete blockage is present, the problem is serious.
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