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Vacation Time!!!!

Jul 22, 2012 | Feed

 

Dr. Lacher spent the week before her vacation running around the clinic trying to make sure Dr. King and our fabulous team were up to speed on all her cases before she headed to Paris for a week.  She assured me she would bring me back something tasty from France so I allowed her to go.  Along with making sure we have good communication in the office, Dr. Lacher all her animals at home were taken care of.   I thought I would let you in on her preparations for leaving since I thought it was great information for all humans.

First thing Dr. Lacher did was to make sure she had plenty of feed and hay for the horses, and was stocked up on cat and dog food.  She went through her feed room to be sure she had her feeding board up to date.  Her feeding board was, of course, out of date with one horse listed in the wrong stall and a few on their winter feeding amounts.  Making sure these details are clear for her farm sitter will minimize any confusion while she is gone.  While in the feed room, Dr. Lacher made sure there was enough Myristol, Solitude, and One AC for the non-sweaters.  She added a bucket of homemade electrolytes just in case the horses sweat overly much one day or someone wasn’t drinking enough.  Recipe:  two containers of Morton Salt Balancer, or two regular salt and two lite salt containers, and 10 ground up Tums.

In the barn, Dr. Lacher made sure all the stalls were labeled with the horse’s name and that halters and lead ropes were in obvious locations.  Dr. Lacher tried to make sure that all those little things we put up with, such as the snap that isn’t quite right, were fixed up.  On her last stall cleaning she made sure she added a little extra bedding and made sure they were super clean.  She gave all the water buckets an extra scrub and generally did a bit of tidying up.  While her farm sitter is excellent, it makes it flow a little easier to have things a bit “over” ready.  Just like most farm sitters, Dr. Lacher’s has places to be after taking care of her farm and she tries to get her in and out as quickly and efficiently as possible.   Finally Dr. Lacher made sure that an extra copy of the feeding and turnout instructions were posted in the barn aisle and e-mailed a copy to her farm sitter.

Now that all the concrete work was done Dr. Lacher sat down to work on the hard part:  paperwork.  Dr. Lacher filled out an owner/agent form for each of her horses, cats, and dogs.  This form allows her to designate her wishes for each of the animals.  There is a location for what kind of procedures are allowed and not allowed, and a monetary amount she is willing to spend on each animal.  It also legally allows her farm sitter to authorize veterinary care up to the designated amount.   The form has a paragraph designating what to do in case euthanasia should be necessary.  This form makes sure everyone knows what should be done with each animal in case anything is necessary!  These forms, along with all contact information are placed in a folder readily visible for the farm sitter.

It’s hard going on vacation and leaving us furry kids behind but with the proper preparation you can be sure we will be well taken care of!

May your litter box always be clean and your food bowl full!

 

Horse Breeding for Dummies Part 6 – Stallion Basics

Jul 12, 2012 | Breeding

 

What a week! I am exhausted just from watching the clinic staff in recent days – Springhill Equine has been in full swing for breeding season these past two weeks! In honor of that, I felt it was time we continued our discussion on horse breeding. This week, I would like to segue into the male side – basics of management of stallions and geldings. A stallion is a male horse that has not been castrated and is sexually mature (vs. a colt, which is not mature). A gelding is a stallion or colt that has been castrated. Sexual maturity is reached at about 4 years of age, but many colts will exhibit stallion-like behavior and sexual activity as early as 8 months of age. They should be separated from females when this is observed.

Castration, or removal of the testes and associated structures, is commonly performed on horses, as stallions can be tricky and difficult to handle and manage. Stallions are often housed in facilities separate from mares so no accidental breedings occur. They must be handled with a firm but cautious hand. With all of this said, there are many stallions out there who are considered docile and easily managed.  Geldings that are castrated before significant stallion behaviors develop, on the other hand, make wonderful companion and riding animals, and are generally more docile. If a stallion is castrated later in life (eg, more than 2 years of age), stallion-like and/or aggressive behaviors may persist post-castration. It is not recommended for the beginner horse-person to own a stallion – usually males are only kept stallions (or ‘intact’) in situations where they will be specifically used for breeding purposes. Some are left intact until physical characteristics develop (eg, larger size, crested neck), and are then castrated. Thoroughbred racehorses are often kept as stallions so they have the potential for a breeding career if their racing career proves successful.

Let’s talk more about the specifics of the male horse reproductive tract. As with any mammal, both stallions and geldings have a penis as their external genitalia. Unlike humans, however, the male horse’s penis at rest is telescoped within itself, and is housed inside the body during the majority of the time. He will externalize the penis (as one would extend a telescope) during times of sexual arousal, for urination, or during sedation/relaxation. There can be medical issues that result in the horse becoming unable to retract the penis, and can become a major problem if left externally for an extended period of time (just like they say on the Viagra commercials – 4 hours is too long!). Tumors and other skin conditions of the penis are relatively common in horses, so regular cleaning of the dirt and skin oils (termed ‘smegma’) from the penis and sheath is important. The vets here at Springhill Equine clean any male horse who is sedated for a dental float, and check them thoroughly for any signs of cancer or other abnormalities.

Stallions also have a pair of testes housed externally in the scrotum. Veterinarians are aware of several conditions that can arise with the scrotum and testes – including infections, tumors, testicular torsions (a medical emergency that presents often as severe and sudden colic), and scrotal hernias. The testes is the assembly factory for sperm, while the next-in-line epididymis is responsible for sperm maturation – eg. packaging and storage. On ejaculation, the sperm leave the tail end of the epididymis, where they are waiting in storage, and travel up toward the pelvis along the ductus deferens (analogous to the vas deferens in humans) until they dump into the urethra (also the exit for the urinary tract) at about the level of the anus. Fluid is added from three different glands (bulbourethral glands, seminal vesicles, and prostate) to help the sperm along their journey. They travel along the urethra through several feet of penile tissue (whose base is just below the anus internally) before exiting with the goal of seeking an egg. In our next blog, we will discuss the various routes a sperm can take to reach that egg – with the stallion actually breeding a mare, or via artificial insemination (A.I.) with fresh, cooled, or frozen semen.

Thanks for stopping by to read my blog this week, maybe next time I could see you in person at the clinic (for some pets)! Keep emailing if you have any specific questions you would like me to cover in my blog (or in the newsletter, for that matter!)! May your litter box be clean, and your food bowl full!

 

Three Easy Ways to Afford Your Horse!

Jul 2, 2012 | Feed

 

I was listening in on some phone calls this week, and learned a ton about the latest in financing options that Springhill Equine offers to help our clients provide the best care to their horses (I figured we just took cat food and treats as payment, but apparently we offer loads of other choices). Just so we are clear, Teenie and I are happy to continue to work for food (particularly Pounce).

The most exciting thing I learned about was Payment Banc. This option allows our clients to pay via an automatic withdrawal from a checking or savings account. Whether you want to pay monthly or weekly, ANY frequency can be set up – allowing for amazing flexibility. This program allowed one of our clients to perform extensive dental work on a geriatric rescue horse for just $70 down. Our Doctors performed an extensive float, and the horse was finally able to comfortably chew when they were finished. It will save her a ton in feed costs (instead of having that money dropped on the floor of his stall) as we get him back to a normal weight. The client was very excited since Payment Banc allowed her to spread the work over six weeks instead of one lump sum. The Doctors recommended bloodwork to check for Cushing’s disease (PPID) and X-rays of his front feet as well (to check for laminitis). Once the horse has had time to get back in shape, our client will add on to her payments so she can continue to provide the best for this fantastic old guy! This client told me (ok… well actually Marilyn, but I was right there on my cushion!) that application was quick and easy. She said a “soft credit check” was performed, but it did not impact or even register on her credit report. I have no idea what all that meant, but it sounded important to the client.

A second option I heard about in the office was Care Credit. This works like a credit card that is specific for health care providers. Many people apparently already have it for use with their doctors and dentists. Much like a credit card, Care Credit sets a credit limit. You are able to charge up to that limit with your healthcare provider. It is a great option for those sudden and unexpected expenditures – like the late-night colic that always happens just before payday! After you apply online and are approved, Care Credit offers INTEREST FREE payment plans for the first 6 months. Be aware, however, that Care Credit does revert to a large interest rate once the promotional period is complete (just like other similar offers from retailers like Best Buy).  Just like Payment Banc, Care Credit allows you to add on when more services are provided. The biggest difference is the interest at the end. I have heard our clients talk about using Care Credit for major procedures, like colic surgeries or tooth extractions, while Payment Banc works better for minor procedures or routine services.

The last great option I heard about was recurring credit card payments. We are able to set up payments as often as once weekly on Master Card, Visa, Discover, and American Express. One client spread her payments for an extensive lameness evaluation over a two month period, while still earning points on her credit card! This client planned to go to the Quarter Horse Congress this year, and jokingly told us that all the points would help!

I must say, I expanded my knowledge of the many options we offer to make sure our clients can take excellent care of their horses. Our Doctors never want you to have to compromise on your horse’s care on account of your finances! And of course, may your food bowl always be full and your litter box clean!

 

Exciting new eye med!

Jun 3, 2012 | Ailments

 

Hallo there! Another day in the world of Tony here (just waiting for the Monday to come so I have all my people paying attention to me again). This weekend, watching the vets prepare another edition of our monthly newsletter, The Naughty Pony, I was amazed at what Dr. King had to share about a new eye medication called Equitrx Corneal Repair drops (from Bayer). I mostly stole this week’s blog from the newsletter, because I think as many people as possible need to know why they need to call us quickly when their horse’s eye becomes painful.

The vets at Springhill Equine have experienced recent success in treating ‘fresh’ corneal ulcers, thanks to a new medication. Corneal ulcers – defects or scratches on the outermost surface of your horse’s eye, are a serious problem for you and your horse. The new medication is for ulcers recognized in the first 24 hours, so we encourage you more than ever to call us IMMEDIATELY if you notice your horse has a painful eye.

Dr. King first learned about the medication, called Equitrx Corneal Repair drops, when a Bayer representative presented at a University of Florida Equine Club meeting (UF SCAAEP). She has subsequently prescribed the medication to appropriate cases with great success. Corneal ulcers are a particularly frustrating and potentially expensive problem for horse owners in Florida. The cornea, the outermost clear surface of the eye, not only is part of the sphere that keeps the eye inflated, but is the window to the eye. It contains no blood vessels and no water, thanks to special water pumps inside corneal cells – and this is how this thin layer stays so clear. An ulcer is a disruption in this outer surface – from a bump, poke (hay and grass heads are common culprits), or who knows what. Sometimes the defect heals quickly over in the face of infection, and what is called a ‘stromal abscess’ results.

The cornea itself is made up of three layers – akin to a hamburger (meat between two buns). A corneal ulcer disrupts some portion of the top bun and the meat, but can erode down and or/through the bottom bun. A stromal abscess is in the meat with both buns intact. It can rupture into the eye, or out. The scariest part is that the bottom bun is only 2 CELLS thick! The corneal layers are extremely sensitive to pain – which is why if you try to poke a horse in the eye, he reflexively shuts it. This ‘corneal reflex’ is one of the last reflexes to leave a horse when it dies, and can be used by veterinary staff to measure depth or level of anesthesia.

If your horse suddenly has one painful eye (squinting, eyelid drooping, tearing), a corneal ulcer is suspected until proven otherwise. If we see your horse, we will look in the eye, and can often see the defect in the surface, and in later stages blood vessels and/or surrounding edema. Blood vessels and edema obscure the window, making it hard for your horse to see. We will stain your horse’s eye with florescein, a bright green dye, which binds to the meat of the cornea. The amount of stain will show us how big and where the ulcer is. It can also help differentiate a corneal ulcer from a stromal abscess.  Florescein does not bind to either bun, so in the worst cases, there is no stain in the middle of the ulcer (bottom bun), and a ring of green where the meat is exposed. These are medical emergencies and generally are treated surgically, which is usually close to and potentially significantly more than $5,000 by the time the ulcer has healed (usually weeks to months). Appropriate medical treatment for the average ulcer can easily reach $700-$1200 in 1-2 weeks of treatment, if hospitalization is elected (and strongly recommended) at Springhill Equine or a referral facility.

The first medication used to treat corneal ulcers is an antibiotic ointment applied directly to the affected eye. This allows the ulcer to heal free of infection, which will constantly and continuously work against and erode the healing cornea. Another significant potential for infection comes from fungi, which are unfortunately abundant in Florida! Fungal infection results in a ‘melting ulcer’ – where the cornea literally appears to be melting away (droplet-like) from the site. These are extremely difficult to deal with, aggressive antifungal treatment is necessary (eg, hourly, 24/7) to save the eye, otherwise surgical treatment may be required (removing the eye as the battle fails).

Atropine is also used as a topical eye ointment, to dilate the eye keeping it more comfortable. Banamine is used as well to keep the horse comfortable (it appears to work better than bute). A variety of other topical medications can be added into the regimine based on severity. However, without corneal healing, these treatments are for naught. This new product, which contains hyaluronic acid (a viscous fluid that we inject into joints), provides a scaffold over which the healing corneal cells can move. Dr. King has seen healing within 24 hours in 4 out of 5 horses she has prescribed it to (the 5th was particularly large/severe and required several weeks to heal). These cases all fit the appropriate criteria for the company recommends for treatment (eg, they were certain to have occurred in the last 12-24 hours).

I am convinced, as is the rest of Springhill Equine, that this new product holds a great deal of promise for horses attended within 24 hours of injury. We recommend, now more than ever, that you please call us IMMEDIATELY if you notice your horse has a painful eye, to save you and your horse a potentially long and painful process! Thanks for reading, and may your litter box be clean and your food bowl full!

 

Bot, oh Bot!

May 25, 2012 | Ailments, Pests

 

Ever wondered what those tiny yellow dots are at the end of the hairs on your horse’s chest, legs, and undersides? While many people have heard of ‘bots,’ they are often mismanaged and can seem to be a never ending problem, particularly in year-round warm of Florida.

The life-cycle of the bot-fly is centered on the horse – a bot is the larval stage of the adult bot-fly. They can be extremely irritating, and the irritation the horse experiences perpetuates the life-cycle.  The cycle begins when the bot-fly (which resembles a small yellow honeybee) lays the small yellow eggs on your horse’s coat.  When the horse licks, rubs, or bites the area of the coat where eggs are laid.  Irritation by the horse stimulates the larvae in the eggs. The threadlike juveniles move into the horse’s mouth, where they burrow into the gums. Here they remain, nestled between teeth, for about four weeks.  Then they move into the stomach, where they attach to the walls and grow to a fat red bean covered in rows of black spines. They mature and move through the remainder of the digestive tract, emerging with the feces when they are ready, and burrowing into the ground until adulthood is reached. One complete cycle takes approximately a year. Thanks to the Florida weather, what it typically a seasonal nuisance is a year-round infestation.

Bot-fliescan affect humans as well as animals, so diligence is important when caring for a horse with a bot problem.  There are three species:  the common bot (Gastrophilus intestinalis), the throat bot (Gastrophilus nasalis), and the nose bot (Gastrophilus haemorrhoidalis). They each tend to lay eggs in a particular area. The common bot lays eggs over the body, the throat bot’s eggs are generally under the neck and jaw, and the rare nose bot focuses on the lips. Ulcers (or larvae) can sometimes be found in and around the mouth, and teeth may be loose or have nearby pus pockets. Colic and gastric ulcers can be caused or exacerbated by bots, whether from direct damage or blockage from a mass of larvae. Inappetance, diarrhea, choke, weight loss, lethargy, and general unthriftiness can result from infection. Other complications include anemia, stomach rupture, and peritonitis (infection in the abdominal cavity).

Diagnosis is by simple fecal exam – they can collect a sample at your appointment, or you can drop a fresh ‘apple’ by the office for Danielle & Michelle to process. You can collect it with a zip-lock bag within 2-4 hours of passage, and store it in your fridge (up to 24 hours) until you can bring it to us. Sometimes larvae are discovered in the soil, or in your horse’s feces, mouth (eg, during a dental). Worms are easily identified in the stomach on gastroscopy (putting a 3 meter camera into the stomach), or rarely in the gastric reflux when tubing during a colic.

Treatment is simple enough, ivermectin usually does the trick – but wait until the average temperature is above 80 degrees F. Prevention is more difficult – good fly control measures and careful removal of eggs. Again, be aware – bot-fly larvae have been found in the skin, eyes, and stomachs of humans. Eggs should be removed from the skin with a bot knife, which is used to scrape the side of the skin to remove the eggs without injuring the skin. A grooming stone/block, pumice stone, and clippers also work well. As many eggs and hairs should be caught and disposed of as possible – preventing eggs on the ground from being ingested. Keep these simple tricks in mind, and you will find it is a problem worth managing!

As always, may your litter box be clean and your food bowl full!

 

The Flies Have It!

May 20, 2012 | Ailments, Feed, Pests

 

This week I thought I would blog a bit about that dreaded summertime pest:  the fly.  Teenie and I were having a movie night and I chose The Fly in preparation for this blog.  She smacked me, told me I had poor taste in movies, and stomped off to sit at the front desk.  Girls.  I just don’t understand them.  Oh well here goes, all I have learned about flies while hanging around the office.

To start with the most common species we see are the stable fly and the house fly.  The house flies are annoying, spread disease, and are generally a pain in the rear.  Stable flies are all that and they live off blood so they bite us and our horses.  Each of these critters enjoy having babies in a mixture of hay or straw, feces, soil, and grain.  Sound familiar?  During my inspections of the stalls at the office I have found this combination of things are quite common around horses.  The stable fly can go from egg to fly in as little as three weeks and the house fly can do the same in as fast as ten days in the summer!

I see many people spraying their horses with loads of sprays trying to keep the flies away but my keen cat sense has determined that this doesn’t work very well.  My research found that sprays work well to knock down adult flies but don’t have much residual effect to keep them away.  Some sprays contain scents that flies find mildly offensive but this approach is better for gnats and mosquitoes.  One insecticide option that can work with flies are products like QuickBayt.  This product is sprinkled on the floor or can be mixed with water and sprayed on vertical surfaces like walls or posts were flies hang out.  When flies come in to contact they are killed.  The product is very safe for children and animals.  Dr. Lacher has proven this at her house when her dog ate a few mouthfuls before realizing QuickBayt tastes horrible.  The manufacturer did this on purpose to minimize the risk of dogs and children thinking it tastes great.

So what does work?  The best way to minimize flies is to minimize their breeding grounds.  Keeping stalls meticulously clean and dry is the most important first step.  It is extremely helpful to remove any hay mats left over after round bales are finished.  Lift one of those mats up and you will find a fly baby making machine!  Composting, when done properly, kills the fly eggs before they can mature.  There are numerous web sites with excellent tips and tricks for composting (hmm future blog?).  One excellent link is http://www.puyallup.wsu.edu/soilmgmt/composts.htm  Spreading manure helps dry the manure quickly and, well, spread it out making less fly friendly.  Managing manure has to be the first step in fly control.  None of the other methods can overcome poor manure management.

Feed through controls.  There are two main brands out available:  Solitude and SimpliFly.  Solitude contains a compound called cyromazine.  Cyromazine is not active until it passes through the intestinal tract and is deposited in the manure.  From there it is eaten by the larval stages causing them to die.  Cyromazine is generally considered safe for all ages of creatures.  SimpliFly contains a compound called diflubenzeron.  This compound is a little trickier to pin down on safety but is generally considered safe for adult animals.  Diflubenzeron prevents the larva from making chitin so they can’t progress in their life stages to adulthood.  The big advantage to feed through control is it delivers the compounds around the farm.  Anywhere your horse “goes” your feed through goes.  They are also very easy to administer since both are in an alfalfa pellet base.

Isn’t there a way to manage flies without chemicals?  Why yes there is I say.  They are called fly predators.  These are tiny relatives of the big wasps we all see.  They selectively lay their eggs inside fly eggs and their kids eat the baby fly.  I love these critters!  They can’t quite keep up their end of the baby making equation so you must spread extras around every month to keep up.  Fly predators do a pretty darn good job as long as proper numbers are used.

I have to add one more management method:  let the cat chase them. I find this to be the most fun of the options even if it isn’t very effective.  If you find flies are driving you and your horses mad, call us for help finding an entomologist who can help you determine the best plan for your property.  And that’s a wrap for this week.  May your litter box always be clean and your food bowl full!

 

Horse breeding for dummies, part 4 – Pregnancy Diagnosis

Horse breeding for dummies, part 4 – Pregnancy Diagnosis

May 6, 2012 | Breeding

Hey all! How are you all doing this week? I’m feeling especially important and accomplished, as I successfully pranked all of the Springhill staff this week! It was a beautiful Thursday afternoon, and I had been lounging peacefully in the office as the last appointments of the days drew the ramp up on their trailers. I quickly and quietly slipped away, however, before the crew started the close the front door to keep us up for the night. As closing time approached, I could hear Marilyn (our new office manager) yelling my name and shaking the treats. Later on, I heard Dr. King pull in and she also spent about 30 minutes calling my name. I could hear her on the phone with a frightened Dr. Lacher, discussing my absence. She also called to see if I had hitched a ride home in someone’s trailer. I watched as she walked to the road, looking at black tire scraps and continuing to yell. Finally, I decided to give up my jib and came up to the clinic. Dr. King hugged me and yelled at me, then fed me treats, scolding and petting me some more. I was a little confused, but glad to be rid of the spiderwebs that had clung to my fur on my adventure.

Anyway, we are supposed to be discussing breeding. We have been discussing the many aspects of the cycle of the mare, from seasonality to the hormones involved, the appearance of the uterus and ovaries when the mare is in and out of heat. We will discuss more about the actual breeding in the near future (semen will be covered with the stallion), we are going to assume that your horse has been bred and it is time to look for a pregnancy!

14 day embryo

We typically suggest a pregnancy check at day 14, when the embryo is large enough to be detectable by ultrasound, but when it is in the stage of moving around the uterus. A horse embryo rolls around the uterus for an unknown reason – presumed to be associated with the mare’s recognition of her pregnancy – prior to finding a spot to nestle in. If there is any chance your horse has had a double ovulation, it is critical that your horse be checked between day 14 and 16 post-ovulation. This is the optimal time to reduce twins before the embryo fixes and implants at day 17-18. To reduce a twin pregnancy, the embryo is “pinched” or crushed, with the aim of allowing one of the two twins to survive. This is easiest when they are small and mobile.

This sounds awful, but you must remember that while twin pregnancies do occur and survive to delivery, it is extremely rare to have a pair of twin horses survive to a year of age. A growing foal demands that their placental surface cover all available surfaces of the uterus, so sharing simply isn’t tolerated. Twin pregnancies that aren’t reduced result in one or both foals aborting, or they are born mummified, dead, weak, and/or undersized, and many born alive die soon after birth. If having one healthy foal survive a twin pregnancy is lucky, having a pair is a miracle. The 14-16 day embryo is the best time to manage this condition.

Many older mares have cysts in the lining of their uterus. If we have seen your mare before, we have an idea of where her cysts are located along her ‘Y’ shaped uterus. Cysts and embryos can appear similar sometimes, but the primary difference is that cysts remain the same in size and location, and embryos move and grow. One can imagine a cyst as a peg on a pinball machine, where the ball (embryo) can be delayed, stuck for a moment, or stopped completely if there are a number of them in a group. If there is any question if the structure seen is a cyst or an embryo, a check in hours or days will usually reveal the answer.

Once a single pregnancy is confirmed at 14-18 days, we also recommend checking your mare at 25-30 days. At this time, we look for a heartbeat, which will confirm that the embryo is alive and well. If it is not, we recommend giving the horse prostaglandin to lyse the CL, terminating the pregnancy before the endometrial cups form. Once these structures form, if the pregnancy is lost, the horse will be finished for the season. It will take the rest of the breeding season for the cups to resorb and uterus to return to normal.

Well thanks for stopping by to read my Blog! Until next week, keep up with your own pranks, and stop by to give me some pets! May your litter box be clean and your food bowl full! 🙂

 

Vaccine Clinic Cliff notes and Dr. Lacher’s Itchy horse update!

Apr 30, 2012 | Ailments, Pests

 

I had a really great week this week.  Thursday evening we had a seminar on vaccines here at the office.  I LOVE seminars.  It gives me a chance to meet my adoring fans up close and personal.  I also enjoyed a bit of cheese from Villagio’s pizza and we all know Villagio’s is never a bad thing.  For those of you who missed out on the seminar I thought I would summarize what Dr. Mackenzie covered.  Next week I will return to my breeding for dummies series.

Dr. Mackenzie covered several topics regarding vaccinations.  She divided it up in to three main categories:  Evaluating the horse to be vaccinated, geographic specific differences, and biosecurity.

The most important category is the evaluation of the horse.  Dr. Mackenzie talked about evaluating the age of the horse.  Dr. Lacher and Dr. King are always talking about this very thing around the office.  They say that while age is not a disease it is very important when picking vaccines.  Young foals must begin with a series of vaccines to prime the immune system.  The timing of this series is very crucial.  It turns out all those good things foals get from mom’s milk can also interfere with our vaccines!  Knowing a history on the mom whenever possible makes our doctors’ job much easier.  Senior horses may need vaccines more often as well if they are experiencing signs of Cushings disease or are otherwise down on their health just a bit.  Dr. Mackenzie emphasized how important is to have Dr. King and Dr. Lacher give your horse a good check-up to determine they are in good health.

Next Dr. Mackenzie discussed the differences around the country and the world.  For instance, here in Florida we have to vaccinate for the mosquito born encephalitis much more frequently than our more northern friends.  One reason is the presence of mosquitoes all year! But we don’t have diseases like Botulism or Potomac Horse Fever.  Geography also involves your horse’s lifestyle.  A horse that doesn’t leave the property doesn’t necessarily need vaccination for Rhinopneumonitis and Influenza.   Once again Dr. Mackenzie emphasized a partnership with Dr. Lacher, Dr. King, and you to determine your horse’s health and what vaccines are required based on your lifestyle.

The last topic was biosecurity.  Here Dr. Mackenzie emphasized taking temperatures! A lot of taking temperatures!  She talked about taking daily temperatures to establish what is normal for your horse and then again after any trips or exposure to new horses.  We also talked about the importance of quarantines.  New horses should be kept separate for at least three weeks.  She also recommended nasal swabs to determine if they are shedding any viruses and fecals to check for parasites. Dr. Mackenzie sure sounded a lot like Drs. Lacher and King when she talked about making sure you have your own water buckets at group events, making sure the hose doesn’t touch the water in the bucket, and limiting nose to nose contact with strangers.

A few other points Dr. Mackenzie covered concerned the nature of vaccines.  She pointed out that vaccines contain two main components: antigen, or the disease we are vaccinating for, and adjuvant, the part that notifies the immune system.   Most of the vaccines we give our horses are killed vaccines.  This means the organism has been inactivated and then combined with an adjuvant.  These vaccines are very stable and cheap.  However, they don’t stimulate an immune response for very long so we have to give these vaccines at least every six months.   We do use one vaccine that is modified live and that is the Intranasal flu.  Modified live means the organism has been altered so that it grows in the horse a very small amount once given.  These vaccines don’t require an adjuvant and offer long lasting protection.

Overall I really enjoyed Dr. Mackenzie’s talk and learned a lot about how, why, and when we give vaccines.  And I once again, learned how important Dr. Lacher and Dr. King are to our horse’s healthcare!

Completely changing topics briefly.  I spoke with Dr. Lacher this week about her horse, Angie’s, response to immunotherapy (allergy shots).  Dr. Lacher tested Angie with our new intradermal skin testing and found she was allergic to all kinds of weeds and trees.  This explains why Angie was still very itchy despite all Dr. Lacher’s efforts to control her culicoides, or gnat, allergy.  Angie has been on allergy shots for about three weeks and is much more comfortable!  Dr. Lacher said Angie normally has her mane and tail itched out by now even with a full fly sheet, fly mask, and daily fly spray.  Now she looks great and no more daily fly spray.  Though Angie still wears a fly sheet and mask for turnout.  Dr. Lacher was very excited about the results!

Well that’s all I have for this week.  May your litter box be clean and your food bowl full!!

 

Reproduction for Dummies Part 3. The hormonal cycle of the mare

Apr 22, 2012 | Breeding, Uncategorized

 

Hay there! The birds, bees, and butterflies seem especially active this week, so I decided another blog on the birds & the bees was appropriate. Last week we introduced the reproductive tract of a mare, its anatomy and function, particularly during the transition into cyclicity. We discussed how the ovary parents the behavior of the uterus and cervix with the presence of large follicles. We introduced that when a large follicle is present, uterine edema (increased water or turgidity) makes thick, welcoming folds, both ready for an egg to come settle in, and an open pathway for sperm to enter through the cervix, and that all of these factors must be present for a mare to be ready for breeding.

The ovary parents the behavior of the uterus and cervix because the of the nature of the hormones being secreted by the various structures on the ovary, and the pattern of blood flow to these structures. These hormones largely change the pattern of blood flow to the uterus, making the layers and folds relatively more or less turgid. Estrogen, which women can thank for most of their complaints in life, increases blood flow to the reproductive tract and relaxes (opens) the cervix – the entrance to the uterus. Estrogen is produced in significant amounts by these magic 35-38mm (dominant) follicles. Whether or not we use deslorelin to help us time ovulation, the follicle ovulates when it is ready, releasing the egg to descend to the uterine horn.

Once the follicle ovulates, which can occur on one or both ovaries, the remaining tissue collapses on itself and begins to transform into another ovarian organ – the corpus luteum (CL). The CL produces the hormone progesterone, which changes the reproductive tract whether or not a breeding and/or pregnancy occurs. Progesterone prepares the uterus for and maintains pregnancy. It reduces uterine edema and closes the cervix tight, so nothing can get in (or out). This is the toned, ‘out of heat’ uterus.  We measure progesterone to determine if the mare has reached cyclicity during the spring transition because it will only be produced in significant amounts if the ovary has produced a follicle large enough to ovulate, and result in formation of a CL.

The CL is destroyed by Prostaglandin (I know, it sounds annoyingly similar to progesterone). Prostaglandin is produced by the uterus when no pregnancy is recognized after more than 2 weeks, and during times of inflammation (eg, infection in the uterus). Prostaglandin will only kill the CL once it is mature enough to recognize it – 5 days post-ovulation. This is significant when it comes to ‘short cycling’ a mare. If, for whatever reason, breeding cannot occur this cycle, we can give the horse a shot of prostaglandin (‘prostin’ or Lutalyse) in the muscle to ready the horse for breeding much more quickly. Another time prostaglandin is significant is if a mare double ovulates, and twins occur. If we diagnose twins and crush one for the sake of the other, the inflammation from the act of crushing can result in the loss of both pregnancies.

In review – there are two major ovarian structures, and corresponding hormones, that dictate how the uterus and cervix behave. An egg-containing follicle produces estrogen, which readies the tract for breeding. A corpus luteum (CL), which forms from the ovulated follicle, produces progesterone which readies the tract for pregnancy. Prostaglandin will result in lysis (rupture or death) of the CL, which can result in short-cycling of the mare, or termination of pregnancy. If this summary does not make sense, reread the above blog more slowly.

Don’t forget about our Vaccine Seminar THIS THURSDAY, April 26th at 6 P.M. at the clinic (PLEASE R.S.V.P.!)!  We look forward to seeing you there, and don’t forget to come give me some pets! May your litter boxes be clean and your food bowls filled!

 

Breeding for dummies part 2….

Breeding for dummies part 2….

Apr 15, 2012 | Breeding

I hope everyone had a great week and that you came out to say “Hi!” to the Springhill Equine folks at the Alachua Spring Festival.  I know the staff and Doctors always look forward to the festival and its great vendors and activities.  And continuing on our Spring theme, this week I am going to discuss the changes mares go through in Spring and Fall and during a normal cycle.  These changes are very closely monitored by our Doctors by ultrasound to help them determine the best time to breed.

Last week I covered that horses are seasonal breeders during long daylight hours.  Determining when that optimal amount of daylight happens to have our mares cycling is the tough part!  To begin with our Doctors rectally palpate the ovaries and uterus.  Normal ovaries are about half the size of a human fist, getting slightly small when the mare is out of heat and larger when in heat.  During the winter the ovaries shrink down to the size of walnuts.  The uterus on a normal cycling mare varies in tone during an estrous cycle (the period between ovulations).  When your mare is in heat the uterus is very loose and floppy, when she is out of heat it is firm like a well toned muscle.  If a mare is not yet cycling the uterus feels loose and floppy but the ovaries are small.  So palpation is the first clue.

Next an ultrasound machine is used to look at the ovaries and uterus.  Again our Doctors find that mares who are not cycling will have small ovaries with very small (less than 10mm) follicles and a uterus that feels like an in heat uterus but looks like an out of heat uterus (more on the difference later).  If in doubt our Doctors will pull a progesterone level.  A small amount of blood is taken and tested to determine if these levels are low, high or in the middle.  Mares who are not cycling yet will be very, very low.

Now comes the tricky part….Before mares actually ovulate for the first time in a season they build a few big follicles which don’t ovulate, the uterus starts to have tone and everything looks like it is headed in the right direction only to stop just before ovulation occurs.  This can mean several ultrasounds a few weeks apart to determine when your mare is finally ready for breeding!

Dr. Lacher and Dr. King have determined your mare is cycling and we can now work on breeding her.  What the heck does that mean and what are they looking for to determine the perfect time to order semen or send her to the stallion?  Three things have to happen for everything to be perfect: a follicle of 35-38mm in size, a uterus with a hint of edema, and an open cervix.

The ultrasound image below would be what Drs. Lacher and King would be looking for.  They would measure across the black circles to determine when one reaches that magic 35-38mm.

Ovary

Uterus

They will also be looking at the uterus to see if there is any edema present.  Edema is a very normal part of the cycle.  The edema is seen in the image on the right and makes the uterus look like a wagon wheel or orange slice.  Once at least a small amount of edema is present, a follicle of the correct size is seen, and the Doctors palpate an open cervix then an ovulatory timing drug such as deslorelin is given.

Drugs such as deslorelin help us precisely time ovulation.  Once given 90% of mares will ovulate within a 36-48 hour window.  This makes ordering semen from far away, making appointments with stallion owners, and timing of frozen semen insemination much easier.

Next week we will talk even more about the joys of the cycling mare and the fun of breeding!  Until then may your litter box be clean and your food bowl full!