Urinary Calculi (UC) Male Goats
Written by Administrator-GL   
Tuesday, 12 June 2007

SMALL RUMINANT UROLITHIASIS

Photos courtesy of Drs. Susan L. Fubini and Peter Rakestraw

The urinary tract includes the kidneys, ureters (small tubes that drain urine from the kidneys to the bladder), the bladder, and the urethra (the tube that carries urine from the bladder and out of the animal).  Urolithiasis — the formation of “stones” or concretions of mucus, protein, and minerals in the urinary tract — is a common problem in male small ruminants and a frustrating one for owners and veterinarians.

Formation of Uroliths
The composition of uroliths (also called “urinary stones” or “calculi”) varies with the part of the country that the animal lives in. The most common uroliths are calcium apatite and phosphatic-based calculi (for example, calcium hydrogen phosphate dihydrate, and magnesium ammonium phosphate or struvite). Silicate and calcium carbonate uroliths also are occasionally seen. 

Urethral obstruction caused by uroliths (Figure 1) is most commonly seen in pet goats and show lambs that have inappropriate nutrition. For example, diets that are high in grain, phosphorus, and magnesium and low in roughage (hay or fresh grass) and calcium will increase the risk of phosphate urolith formation. Normally, a ruminant will remove phosphorus from its body by excreting it into saliva and then out through the feces (manure). High grain, low roughage diets decrease the formation of saliva, so extra phosphorus must be removed from the blood by the kidneys and then excreted in the urine. When diets are too high in phosphorus, the urine phosphorus levels become excessively high, and the phosphorus settles and consolidates into stone-like pellets that can be too large to pass.  These uroliths increase the risk of urinary tract infection and may result in life-threatening blockage of the urethra. Some breeds of sheep (for example, Texel and Scottish Blackface) may be predisposed to stone formation because they tend to excrete phosphorus through the urinary tract rather than the saliva and feces.

Hlth Cond: RumUro_Fig1.jpg

Figure 1.  These uroliths — also called bladder stones or calculi — were surgically removed from a sheep that had been fed an inappropriate diet. 

Diagnosis
Early clinical signs include:

  • Blood in the urine (hematuria)
  • Straining to urinate
  • Decreased urine production
  • Painful urination (dysuria)
  • Prolonged urination
  • Dribbling urine
  • Tail flagging
  • Abdominal pain ( stretching out all four limbs, kicking at the abdomen, looking at the side)









Late clinical signs include:

  • Loss of appetite
  • Lethargy (apparent depression)
  • Abdominal swelling (from a ruptured bladder)
  • Swelling around the prepuce (the skin covering the penis)






Once the animal is severely ill, it may lay on its side and not get up, and eventually it may seizure or die suddenly.

Physical examination findings may include increased heart rate, rapid breathing, and possibly a large bladder.  If the bladder has ruptured into the belly, a fluid wave can sometimes be felt (“balloted”) when pressure is put on one side of the abdomen. 

Most uroliths in small ruminants lodge at the “urethral process” or “vermiform appendage” — a small tube-like extension of skin and urethra at the tip of the penis (Figure 2); the second most common site is at the “distal sigmoid flexure” — an S-shaped curve in the lower half of the penis.  Uroliths trapped in the urethral process can often be felt during physical examination. 

Hlth Cond: RumUro_Fig2

Figure 2:  The urethral process, or vermiform appendage, is a tube like extension (arrows) off the tip of the penis.  Uroliths can become trapped within this tube, blocking urination. 

As toxins build up, blood tests may show high concentrations of blood urea nitrogen (BUN), creatinine, and potassium, which are normally excreted in the urine.  Other blood work changes may include high concentrations of muscle enzymes and low concentrations of sodium and chloride.  Acid may also build up in the blood stream.

Uroliths are often diagnosed with ultrasound of the belly.  The bladder and possibly the urethra can be distended (overfilled with fluid) on ultrasound, and sometimes the stones can be seen.  Some uroliths are visible on radiographs (x-rays), which can be used to determine the number and location of stones. Special contrast studies can be performed with radiographs to determine if the bladder has ruptured (Figure 3).

Hlth Cond: RumUro_Fig3

Figure 3.  Contrast material (red arrows) is leaking from the bladder (green arrows) in this animal.

Treatment Options
Surgery is usually required to remove uroliths or relieve the blockage.  Farm management practices should also be reviewed to determine whether diet or other factors could increase the risk of urolithiasis within the herd.

Urethral Process Amputation — The urethral process is a very short, narrow tube-like structure on the tip of the penis, and because of its location and size is the most common site for uroliths to obstruct. “Amputation” or removal of this process with a scalpel blade may allow uroliths within this process to pass, but recurrence of obstruction is likely, particularly if uroliths are also present higher up in the urethra. If this is the case, additional surgical procedures are needed.


Urethral Process Amputation - snipping off the urethral process

Perineal Urethrostomy — The urethra and its surrounding tissues can be easily felt in the back end (“perineum”) of sheep and goats 2-3 inches below the anus and just behind the rear legs.  When uroliths block the penis or when the urethra has ruptured downstream from this area, a new opening can be made to allow the animal to urinate. This surgical procedure is called a perineal urethrostomy. 
Perineal urethrostomy is sometimes performed under heavy sedation with regional anesthesia (nerve blocks), but in valuable animals or pets it is often performed under general anesthesia. An incision is made through the skin and into the urethra, and the new urethral opening is sewn directly to the skin.  The animal then urinates down and backwards instead of forwards.
Complications of perineal urethrostomy include stricture formation (closure of the hole) in some animals. Also, the animal can no longer be used for breeding since semen does not  pass through the penis.

Tube Cystostomy — In animals with urethral obstruction or rupture, urine must be diverted away from the urethra to allow swelling to subside and tissues to heal.  Tube cystostomy involves surgically placing a rubber tube in the bladder and exiting the tube through the belly wall adjacent to the prepuce (Figure 4). This procedure is performed in conjunction with urethral process amputation and surgical removal of uroliths from the bladder. Once the swelling in the urethra has resolved, any uroliths that were not removed at surgery often pass in the urine either through the urethra or the tube.  Once the animal is healed, the tube can be removed.

Hlth Cond: RumUro_Fig4

Figure 4.  An incision has been made into the belly (green arrows) to open the bladder and remove the uroliths.  Then the cystostomy tube (black arrows) is placed into the bladder and exiting out the belly wall before the abdomen is closed.

 

4 Way Acid Pak for UC prevention

 

Although a tube cystostomy may be performed with sedation and local nerve blocks, general anesthesia is often used. This permits optimal sterile technique and time to remove uroliths from the bladder or repair it if it has ruptured, and allows the surgeon to thoroughly flush the abdomen before placing the tube. Once the tube is in place, it can be attached to sterile collection system or covered with a one-way valve to allow urine excretion. The tube is kept in the animal until urine is seen dripping from the prepuce for 48 hours (Figure 5). Then, the tube is clamped and urination is monitored. If the animal can urinate, is not painful, and is able to empty its bladder, the tube is removed. If the animal can only partially urinate and continues to retain urine, the tube is left unobstructed for 5 to 7 more days and the process is repeated. On average, a tube cystostomy is removed 10 to 14 days after surgery.

Hlth Cond: RumUro_Fig5

Figure 5:  A ram with a cystostomy tube in place.  The tube will be removed once the ram can urinate normally from the penis.  The tube will be temporarily blocked before it is removed to make sure that the urethra is not blocked.

The main complicaton with this procedure is the risk of reobstruction following removal of the tube.  Also, early removal (less than 5 days after placement) or accidental obstruction of the tube could result in leakage of urine into the abdomen (Figure 6).

Hlth Cond: RumUro_Fig6

Figure 6:  The cystostomy tube (green arrow) has accidentally been pulled out of the bladder and is now leaking urine (red arrow) into the abdomen.

Prepubic Cystostomy — For animals that have strictured (narrowed) perineal urethrostomy sites and subsequent re-obstruction, a permanent opening can be made between the bladder and the belly wall near the prepuce. This procedure is called a “prepubic cystostomy” or bladder “marsupialization”. Urine will leak constantly from this hole, and may irritate the skin (“urine scald”), particularly if the skin around the new opening is not shaved and cleaned frequently.

Because animals with prepubic cystostomy can develop chronic urinary tract infections, this procedure is a “last resort” treatment for pet animals. In addition, the permanent cystostomy can become strictured and obstructed, requiring a second or third surgical procedure.

Urethral Translocation can be attempted to “by-pass” a ruptured urethra (or failed urethrostomy). This also is a “last resort” procedure for pet animals. This complicated procedure involves attaching the urethra in the belly to the lower half of the penis or prepuce.  Complications include loss of bladder tone and function (“neurogenic bladder atony”, with pooling of urine in the bladder and subsequent development of chronic cystitis (bladder infection).

When to Contact an ACVS Veterinary Surgeon
Because of potential complications, advanced urethral surgeries may require specialized training, particularly when the patient is a valuable breeding animal or beloved pet.  Find an ACVS Veterinary Surgeon specializing in Large Animal Surgery.

Breeding Males
Little data exists regarding the effect of urethral process amputation on fertility in small ruminants. However, minimal reduction in fertility (<10%) is expected. When urethral obstruction does not involve the urethral process, breeding bucks occasionally can be preserved using tube cystostomy to manage urolithiasis. When successful, the urethra is preserved, intact, and a normal erection during breeding is expected.  Breeding males should be rested sexually for 1-2 weeks after urethral process amputations and for 2 months after other urethral surgeries to reduce the chance of surgical complications. 

Prevention of Urolithiasis
All show animals that must be fed a relatively high grain diet should have salt (sodium chloride) added into the ration at a rate of 2 to 5 % (alternatively, ammonium chloride can be used at a rate of 0.5 to 1 %) to increase the amount of urine formation or acidify urine. Diets high in calcium may reduce the amount of phosphorus absorbed; owners should always speak to their veterinarians before adding any supplements to the feed. Horse-feed should never be fed to small ruminants because the diet is not balanced appropriately for them and therefore increases the risk uroliths formation. 

— David E. Anderson, DVM, MS
Diplomate ACVS
 

Posted 3/23/2006


The American College of Veterinary Surgeons (ACVS) recommends contacting an ACVS Board Certified Veterinary Surgeon or your general veterinarian for more information about this topic. Search for an ACVS Veterinary Surgeon in your area.

Publication Date: October 18, 2007

URINARY CALCULI
THE SHOW WETHERS WORST ENEMY

Lisa Stacey
The Good Shepherd Goat Farm

Urinary Calculi also know as (Kidney Stones or Water Belly) has become the worst enemy of our 4-H and Open Shows Wethers

Showing 4-H and Open Show Market Wethers has EXPLOEDED throughout the Country! It's a great project for beginners and novices alike. The project teaches feeding, finances, health, general care, sportsmanship etc.

WHAT IS UC

UC is the formation of Calculi (stones or crystals) in the urinary tract. The most common Calculi found in goats on a high concentrate diet is the "Struvite" type.

SYMPTOMS OR SIGNS OF UC

Tail twitching, restlessness, anxiety, kicking at the belly, not wanting to eat, a hunched back as they strain to urinate (this sign is the same as constipation and bloat), groaning or bleating while trying to urinate.

The goat may show one or more of these signs. You must watch carefully to see if the goat is urinating! If you see these signs "REMEMBER" you can not make the goat urinate!

CAUSES OF UC

-High concentrated feeds for a long period of time
-When the calcium/phosphorus ratio gets out of balance
-Castrating or banding buck kids too early
-Not enough water intake
-Sulfur in the water, mineral composition of the drinking water
-baking soda

LET'S TAKE A LOOK AT THE ABOVE CAUSES OF UC

High concentrated feeds for a long period of time: Goats aren't built to eat large amounts of grain. Goats are Browsers and prefer forage such as leaves, poison ivy, multi-floral rose etc. They can live solely on forage with no grain supplement if the forage is plentiful! If there is no forage or pasture available they can be fed a GOOD QUALITY Hay. Goats are ruminants. Their rumens can't work properly if they don't have access to forage/pasture or hay. If you feed commercial feeds (grain or pellets) "THEY MUST HAVE HAY" etc. for their digestive systems to work!
The challenge comes when we are raising the Wethers for show and have a certain amount of time to get them up to weight. So we offer the goats as much grain/pellet feed that we can get them to eat (Remember they are foragers)

The main cause of UC more so than the amount of grain fed is when the Calcium to phosphorus ratio gets out of balance! The calcium to phosphorus ratio in your goats feed should be calcium 2.7 to phosphorus .3 When this ratio gets out of balance you are putting your goat in extreme high risk of getting UC. The way this gets out of balance is when we start adding extra supplements to the already balanced commercial feeds. When you add supplements such as example: corn, roasted soy beans, soy bean mill etc. to the feed (showmen do this to make the goats grow faster, build muscle etc.) you just changed your calcium/phosphorus ratio.
Castrating male goat to early can cause problems also. When we castrate or band young male kids it removes the hormones needed for proper development of the Urinary Tract (the growth of the urethra stops) thus you have a large goat trying to function through a small urethra. The male urethra is long with many twists and turns. Calculi lodges in the winding small urethra blocking the urine flow.

Wethers that don't have access to water at all times can form UC. A pen of Wethers at a college ran out of water for a few hours one afternoon. The next day several died of UC. Water intake is important!

Mineral composition of drinking water especially Sulfur plays a role in the formation of UC. Many producers will have available to their goat's free choice Baking Soda. This is done to help prevent bloating in the goats. However, Baking Soda is also a contributor to UC in male goats.

PREVENTING URINARY CALCULI IS MUCH EASIER THAN TREATING UC

PREVENTION

-Since we must supplement the Market Wethers with grain/pellets, choose a feed high in fiber (at least 10%). Pellet feeds are usually higher in fiber than the grain.
-Choose feeds that are labeled so you know the calcium to phosphorus ratio are in balance 2.7 / .3
-Offer PLENTY of forage/browse or good quality Hay
-CLEAN FRESH WATER AT ALL TIMES. If you wouldn't drink what's in their water bucket then it's time for fresh water
-Add Ammonium Chloride to the feed or water. Some commercial feeds already have this added. Read the label or ask questions!
-Acid Pack Treatment: Add to the water (This is a GREAT product)
-Add 3-4% salt to the feed. This will cause the goats to drink more water and reduce the incidence of UC
-Test you water! You can do this at your local Extension Office or purchase a fish tank test kit. The water PH should be neutral (a PH of 5)
-Buck kids should be castrated or banded NO EARLIER than 3 months of age

TREATMENT

If you suspect your goat has UC "DON'T WAIT" until he isn't urinating to get help. When he stops urinating the hope for survival is almost gone. There is a surgery that can be performed however; it is extremely expensive and not economical. If the Wether is still dribbling urine sometimes treatment will be successful. Take the goat off all grain and feed. Feed only grass hay and water. Call your Veterinarian or a local Breeder for help!

BEWARE of people who tell you not to worry about Urinary Calculi! The number of Show Wethers that die each year is astounding! You have the information!

Don't let your Goat be a statistic

References:
Susan Schoenian, Western Maryland Reasearch & Education Center
Dr. tatiana Stanton, Cornell University, Ithaca , NY 14853
Urinary Calculi in Wether Lambs/Kid, By Richard V. Machen

Last Updated ( Tuesday, 23 June 2015 )