The topic of urinary calculi is filled with myth and misinformation, frustratingly so when owners of male goats are simply trying to figure out how best to protect their goats.
Based on my experience, observation and extensive research, I feel confident in saying that the causes of UC are exactly these, in this order:
- improper calcium:phosphorus ratio in the diet
- genetics
Why Age of Castration is Not on This List
I have a logic problem for you. If you pour grease down your sink drain and the pipe clogs, is it because your pipe is too narrow or because you added grease to it? What happens if you only pour a little grease down the drain every day? Does it stay open because the volume is less, or does it eventually clog up anyway?
I have no idea how this misconception came about that castrating before 8 weeks will cause urinary calculi, but a couple of minutes critically thinking about that statement will tell us that there is absolutely no way the size of a goat’s urethra creates the stones.
If our nutritional base is off, it makes no difference whatsoever how large the urethra is, as anyone who has experienced kidney stones will tell you. At some point, a stone larger than the urethra, no matter its size, will try to work its way through and an acute situation will develop.
The stones themselves are formed outside the urethra so how can we continue blaming castration age, which affects mature urethra size, for urinary calculi? I don’t at all contest that castration age will affect the size of the urethra, but I do vehemently oppose the belief that castration age has anything at all to do with whether or not a goat gets UC.
It is my position that age of castration has no impact on the causative factors we actually do know about for urinary calculi: improper nutrition and bad genetics.
And here’s where myth becomes dangerous, even fatal. Over and over and over again I have read “Don’t feed alfalfa, it will kill wethers,” or words to that effect. This statement has no basis in fact as far as I can tell and it certainly doesn’t resemble my own experience with feeding only alfalfa as my hay ration for more than 15 years to all classes of goats. We have never had a case of UC here.
In addition to alfalfa being blamed for general urinary calculi, there are many well meaning but misinformed sources who claim that urinary calculi formed of calcium carbonate stones (versus phosphorus stones, which are vastly the more prevalent) must be caused by alfalfa because it is high in calcium.
Here’s a study specifically on calcium carbonate UC that seems to indicate alfalfa has nothing to do with increasing prevalence:
“Diet—The primary types of diet were recorded for 311 of 354 (88%) case goats. One hundred seven of the 311 (34%) goats were fed grass or kept on pasture, 74 (24%) were fed grass hay, 37 (12%) were fed alfalfa hay, 55 (18%) were fed commercial foods (type not specified on the submission forms), 26 (8%) were fed whole grains (eg, corn or wheat), and 12 (4%) were fed hay and pelleted grain mixture (pelleted grains blended with vitamins and minerals).”
If alfalfa is to blame, why are all those grass eaters getting it?
The real main cause, which is too much phosphorus in relation to calcium, continues to be perpetuated by this fear of alfalfa, the most ideal source of calcium readily available to goat owners. Instead, owners are feeding high grain and high grass diets, both of which lead to…you guessed it, too much phosphorus in the diet. With no calcium to compensate, we start seeing metabolic disorders.
Judging by the fact that we see variation in the type of stones in cases of UC, I would also wonder at an underlying mineral imbalance that goes beyond just calcium and phosphorus. Magnesium, for instance, plays a vital role in calcium distribution. There’s still so much to discover in this area!
Alfalfa is and always will be my number one choice for hay for all of my goats. If you wanted to get really perfect, as ideal as I can imagine a system being, you’d feed free choice alfalfa in one feeder, free choice grass hay in another and provide minerals in the form of a mineral buffet so they can choose exactly what they need. If an animal developed UC in that nutrition program, I’d feel pretty confident that genetics were the cause and nothing could have prevented it. I’d also not repeat the breeding that resulted in offspring with genetically caused UC, because the devastation we see again and again in goat groups is not worth the couple of extra kids sold.