Urinary Calculi (Otherwise known as bladder stones, "kidney stones", blocked goat or sheep, or straining to urinate!

Urolithiasis in Small Ruminants

(Bladder Stones)

Urolithiasis is a common disease of male sheep and goats. It is most often seen in castrated or wethered males, but may be seen in intact rams or bucks as well. Calculi or “stones” form in the urinary bladder, and partially or completely obstruct the urethra. The animal becomes uncomfortable and may be seen straining, stretching his hind legs behind him, and kicking or looking at his flank. The largest risk factor for development of urolithiasis is feeding grain or concentrates to wethers. Quick identification of urolithiasis in an obstructed animal increases the chances of treatment and survival.

Calculi form can form in urine when the pH is too high (alkaline) or too low (acidic), combined with elevated levels of minerals such as calcium, phosphorus, and magnesium. When the calcium to phosphorus ratio in a diet is less than 2:1, the animals are at an increased risk of developing struvite crystals in their urine, which solidify into calculi or stones. This is common in animals fed pellets or grain, as most grains are high in phosphorus and low in calcium. Phosphorus is usually recycled through saliva and excreted in manure, however excess phosphorus is excreted through the urine, leading to stone formation. Very high calcium levels in a diet can also lead to a rarer form of calcium carbonate stone. Other mineral imbalances may lead to different types of stone formation, each more common in different areas of the United States.

The calculi form in the bladder, and are passed in the urine through the urethra. In females and to some extent intact males, the urethra is larger, allowing the calculi to pass without problem. In castrated males the calculi become stuck, most often at either the very end of the penis, or at the sigmoid flexure (an “S” curve in the penis prior to it exiting the body), due to a narrower urethra from a lack of hormonal influences. The calculi become lodged in the urethra causing swelling and irritation. Initially it may not completely block the flow of urine, and you may notice dribbling urine, or blood-tinged urine spots present in the bedding. Untreated the calculi will completely obstruct the urethra from a combination of swelling, and physical blockage. This causes urine to back up in the bladder, and can potentially lead to rupture of the urethra or the bladder from the pressure.

This is a medical emergency, and veterinary assistance should be sought as soon as possible. Treating urinary calculi involves a combination of pain relief, attempting to dissolve the calculi, and surgical removal of the calculi if completely obstructed.

Preventing the formation of urinary calculi is one of the most important steps a small ruminant owner can perform. Unless they are severely under weight mature wethers rarely ever need any grain. Stopping grain feeding decreases the risk of urolithiasis. Young, growing animals should be fed appropriately for their stage of production, and if grain needs to be fed, a balance of 2:1 or greater, calcium:phosphorus ratio should be maintained. Castrated animals being fed grain may be fed ammonium chloride in their feed or loose mineral if there is a history of urinary calculi. Ammonium chloride acts to acidify the animal’s urine, which decreases the ability to form struvite stones. Animals treated long term with ammonium chloride will temporarily develop the ability to neutralize the ammonium chloride, so it should be dosed as needed on the recommendation of your veterinarian.

Control of Sheep Pests

Control of Sheep Pests
By Ralph E. Williams
Extension Entomologist, Purdue University

The sheep ked (Melophagus ovinus), often called the sheep “tick”, is a common pest of sheep. It looks somewhat like a tick but is actually a wingless fly, grayish-brown in color and 1/4 inch long. Its entire life cycle is spent on the host, except when accidentally dislodged; and it will readily crawl from one animal to another.

Sheep keds live 6-8 months, during which time the female produces about 15 young at the rate of approximately one a week. Breeding is continuous, although slower in winter; and there are several generations each year. Unlike most insects, the female gives birth to full-grown maggots, one at a time, which are attached to wool strands about the neck, inside the thighs and along the belly. Within a few hours after birth, the larval skin turns brown and forms a hard puparium. Fully developed keds emerge from the pupal cases in 2-5 weeks.

Read the Complete Article Here

For the Alpaca-ites Out There (and Llama-ites)

Though its raining and mid-30's as I write this, here in western NY we know that spring is here, and bug season is just around the corner.  As we start thinking about spring for our camelid species, Meningeal Worm Prevention is often first on our list, followed by GI Parasite Prevention, Feeding for Reproduction, and the first thoughts of Shearing Season.  An addition to that list is Spring Vaccines.  

Typically for our alpacas and llamas we have recommended vaccinating using a rabies vaccine and a combination clostridial vaccine, such as CD/T (Clostridium perfringens type C and D and Clostridium tetani), or a 7 or 8-way Clostridial vaccine, depending on your herd health history.

Now depending on your farm location, travel history, etc we may also suggest considering vaccinating for Eastern Equine Encephalitis.  EEE is a blood borne disease that is transmitted by mosquitoes.  It has typically been associated with neurologic disease in horses and occasionally in humans.  Since 2004, EEE has been documented to cause disease in alpacas and llamas in the north east.  Why not before 2004? Much is likely due to the fact that we weren't testing for it, though there has been speculation that the virus has mutated to be able to cause disease in our camelid species.  Unfortunately for us in western NY, there were multiple reports in upstate NY of EEE in horses in 2012, as well as one case in a child and one in a dog.  The majority of cases were in the Syracuse area (surrounding lakes and marshy areas), but there were a few documented cases in animals farther west.

The good news is that research done on EEE in alpacas in the past few years has shown that alpacas and llamas are able to respond to the equine vaccine and produce antibodies against the virus. Unfortunately no challenge studies have been performed yet (exposing vaccinated and non vaccinated camelids to EEE and looking for disease), however the vaccine has been shown to be protective in horses and emus.

So how do I prevent EEE (and other mosquito transmitted diseases)?

• Cleaning up dung piles, cleaning water tanks regularly, and removing any standing water from the farm (Mosquito control).  
• Stabling/stalling animals during high transmission times (dusk and dawn) in the late summer/fall.  (Most cases have occurred between August and October).
• Consider vaccinating with an equine labeled EEE vaccine if your animals are in a high risk area

Update on Thursday, April 11, 2013 by Henderson Equine Clinic

For more information on Eastern Equine Encephalitis in Alpacas and Llamas, check out this article from the Alpaca Research Foundation, written by Dr Daniela Bedenice, DMV, Dipl. ACVIM, Dipl. ACVECC of Tufts University.

http://www.alpacaresearchfoundation.org/papers_reports/ARFBedenice.pdf

Pregnancy Diagnosis in Goats

 

How do we determine if goats are pregnant?

• Watch for return to estrus (heat)
• Wait 4.5 to 5 months and watch for udder development and kidding
• Ballot (bounce/palpate) abdomen at 4.5 months and attempt to feel kids
• Draw blood to test for hormones that are normally elevated during pregnancy
• Ultrasound any time after 32d post breeding

Why do we want to know if goats are pregnant? (why not just wait for kids?)

• Allows for an accurate dry off period in dairy does
• Late pregnant does can be fed differently than non-pregnant does
• Allows us to accurately time pre-kidding vaccines and treatments
• Make management decisions about keeping, depending on ability to become pregnant
• Whether or not to rebreed!

How can ultrasounding my doe help me with my 4H project?

• Ultrasounding between 32 and 50 days post breeding can identify whether a doe is having a single or multiple kids
• Ultrasounding for pregnancy at 32 days post breeding helps make sure open does get rebred, and decreases unwanted extended lactations or keeping open meat does
• Often if there are multiple breeding dates from herd breeding, ultrasound can identify the most likely date of pregnancy
• Confirming pregnancy allows for timely CD/T boosters, pre-kidding fecals or deworming, and feeding your doe for peak milk production post kidding
• Knowing pregnancy status will help CAE prevention programs

How do you ultrasound my doe for pregnancy?

• An ultrasound machine sends sound waves away from the probe (transducer), and records how many bounce back and how long it takes.  It then creates a picture with white being bounced back the most and the fastest and black the longest
• Fluid or air doesn’t bounce back sound waves = black
• Bone or metal sends waves back quickly = white
• For diagnosing pregnancy, the probe is placed against the abdomen, above the udder in the hairless area between the leg and body.  It then sends waves out, and creates an image of what it is pressed against.  If the doe is pregnant, images of the uterus, fluid in the uterus, and the skeleton of the kid(s) are seen.  If she is open, the uterus may not be in front of the probe, and intestines and bladder are seen instead.
• For early pregnancy, days 30-40, sometimes the probe needs to be placed in the rectum to see the small, pregnant uterus in the pelvis.
• Goat placenta:
  • Cotelydons: lumps of tissue on the placenta (kid side) that connect to the doe’s uterus
  • Caruncles: lumps of tissue on the doe’s uterus that connect to the placenta
  • Connected they transfer nutrients from the doe’s blood to the kid’s and transfer waste from the kid’s blood to the doe
  • Mom drives a CARuncle; Kid sleeps in a COTelydon

Why can’t I just blood test?  (sounds easier)

• Blood testing for pregnancy tests for either progesterone or pregnancy specific protein B.
  • Progesterone testing is highly variable because pregnancy may not be the only reason for an elevated level
  • Pregnancy specific protein B testing (BioPryn) is more accurate at identifying open animals (99%), but 5% or more of the does the test say are pregnant may be open. 
• Blood testing can not identify the number of kids
• Having your veterinarian ultrasound your doe develops a veterinarian client patient relationship, which gives you a chance to ask them questions about your animals health, environment, or nutrition, as well as allowing them to legally prescribe drugs for your goats
• You CAN blood test for pregnancy
  • Or, you can have your veterinarian pull blood to test for pregnancy
  • However, it is not as accurate as ultrasound, and cannot tell you singles vs multiples

It’s Time For Lambs, Kids, and Crias!

We at Henderson Equine Clinic are very excited to announce we are now treating sheep, goats, alpacas, and llamas in addition to our regular equine clients.  It is almost spring time, and with spring time comes lambing, kidding, and criating!  Are you ready?

Spring with expectant animals brings lots of questions, planning, and excitement. So I thought I would answer a few questions you might have about your ewe, doe, or female.

Question #1: Is she pregnant?

            Answer: Did you have her ultrasounded post breeding?  If so, you know if she is pregnant, and depending on timing and species, you may have an estimate of how many she is going to have.  If you didn’t ultrasound, did you draw blood for a species specific pregnancy test? (Llama’s and alpaca’s can have blood progesterone levels tested to diagnose pregnancy, though it is less definitive than ultrasound).  Or least specific, did you test breed her if she’s a camelid, or has she been seen to be showing signs of heat or been rebred?

Question #2: When is she due?

            Answer: Breeding dates can generally estimate due date within 5-7 days. 

                        Sheep Gestation: approx. 147 days

                        Goat Gestation: approx. 148-152 days

                        Alpaca Gestation: approx. 335-345 days

                        Llama Gestation: approx. 350 days

Question #3: What should I expect when she starts lambing/kidding/criating? (How long should it take?)

            Answer:

Sheep and Goats: Approximately 10 days before she lambs, the teats begin to feel firm and full of colostrum. Between then and lambing the lips of the vulva slacken and become slightly swollen. In the last hours before lambing, many ewes or does will separate from the flock.  As the uterine contractions start, a thick creamy white mucous, the remains of the cervical seal, is passed from the vulva and contractions of the uterus push the lamb or kid into the cervix, stimulating dilation. At this time the ewe or doe is uneasy, getting up and down, switching her tail and bleating frequently. There may be some straining. This is Stage 1 and can take 3 - 4 hours.

As the uterine contractions become stronger and more frequent, the lamb and amniotic sac are pushed into the dilated cervix. The sac bursts, releasing a watery fluid through the vulva. As the ewe continues to strain, the second sac is pushed through the vulva and ruptures, to release a thicker fluid.  The hooves and nose of the lamb can often be seen in the second sac before it bursts.  The ewe gradually expels the lamb, forefeet first, followed by the head. Once the head, forefeet and shoulders pass, final delivery generally rapid.  This is Stage 2 and should take 1 hour or less (30-40 minutes after first seeing feet).  A ewe lambing for the first time or with a multiple birth may take a bit longer.

The placenta serves no further function once the lamb has been born, and is passed 2 to 3 hours after delivery has finished. Nothing will be passed until after the first lamb has been born. In multiple births, there may be separate afterbirths for each lamb.

Alpacas and Llamas:

Stage 1

The cervix relaxes and uterine contractions propel the fetus into the birth canal. This stage may last 2-6 hours (or longer in first pregnancies). Signs include restlessness, discomfort, increased humming, increased defecation and urination, segregation from the herd and decreased appetite. Many alpacas show no obvious signs of being in first stage labor.

Stage 2

Uterine contractions increase in frequency to aid expulsion of the fetus. The female may lie down and rise up several times; there is abdominal straining; the amniotic sac (or water bag) may appear at the vulva and rupture. (Note: much less fluid is released than in other species). Both forelimbs appear together at the vulva and the head emerges either above or below the legs. Once the head appears, delivery is usually completed quickly but the female may rest before pushing out the shoulders. Most females deliver in the standing position. Stage 2 is usually completed in 30-45 minutes.

Stage 3

The placenta or afterbirth is usually expelled within 2 hours of birth. Alpacas do not eat the afterbirth nor lick their offspring.

Question #4: When should I call my vet?

Answer: Veterinary attention is required if ...

• Stage 1 exceeds 4-5 hours without signs of abdominal contractions.

• Stage 2 extends beyond 30 minutes without any signs of progression.

• Stage 3, if the afterbirth has not been expelled within 6-8 hours.

Now that you have brand new lambs, kids, or crias, enjoy them and watch them grow!

-Dr. Anne