|
|
|
|
|
Worm Control News
October, 2009
|
|
|
Worm of the Month
In this
section, we'll feature an equine parasite each month, with
information on the parasite's life cycle and the health consequences for horses.
This month:
Small Strongyles
Strongyles,
also referred to as bloodworms, come in both small and large sizes. This month,
we're looking at the small ones, since they are currently the most active
threat to horses young and old, particularly horses grazing on pasture, since thousands of larvae can be found on a single blade of grass.
Small
strongyle (Cyathostominae, or cyathostomes) eggs are passed in manure, and go through
several maturation stages in the environment, becoming infective larvae in the
third and final stage. Upon ingestion by the horse, the small strongyle larvae
pass directly into the large intestine, where they encyst into the intestinal
wall. This encapsulation not only protects the larvae from any attacks by the
horse's immune system, it also protects them from many deworming medications.
It's only after they excyst from the cysts that the larvae mature into adults
and virtual egg-laying machines, since an adult female lays eggs almost
constantly. This makes it easy to determine if a horse is infected with
bloodworms, and to what extent, since the worm egg count will be fairly
constant throughout a fecal sample.
Bloodworm
infestation is primarily an issue of a horse's environment. In large pasture
areas, horses will naturally defecate in 'roughs' and graze in 'greens'; this
instinctual response to eating away from
manure piles builds in natural worm
control, however it does tend to result in uneven grass growth. Today, many
pastures are dragged and the grass cut to improve pasture appearance, but it
can result in larger quantities of larvae being ingested by the horses grazing
there.
Small strongyles also love temperate climates, so depending
on your location they can be a bigger issue in winter than in hot summers.
Bloodworms thrive in temperatures between 45-85º F, although eggs can die off
in freezing temps and larvae are killed by daytime heat. Temperatures also
affect the maturation process, with cooler temperatures slowing things down.
Horse
owners can work with the worm's lifecycle to minimize their impact in a
pasture, by keeping horses off the grass during cool mornings, when the larvae
crawl to the tops of the blades of grass, and dragging pastures during hot
afternoons, when larvae have crawled back down to the soil level and exposed
larvae will be quickly killed by heat.
Health
concerns for horses infected by small strongyles can range from diarrhea and
weight loss due to gut inflammation, to more serious issues such as larval
cyathostomosis, which is caused by massive excysting of encysted larvae. Often
occurring in the spring and winter, larval cyathostomosis can result in
impaired gut motility and colic, among other issues. While large strongyles have historically been worse in terms of harm to a horse's health, with some small strongyle populations showing evidence of resistance to some deworming medications, there is cause for concern when it comes to bloodworms.
______________________
If you'd like to learn more, we recommend The Horse as a source of in-depth equine health and welfare articles and news. Access to their archives requires a free account. Here's their website:
TheHorse.com
|
|
Greetings!
Welcome to our very first issue of Worm Control News, from Horsemen's Laboratory. Each month we'll be bringing you news and information about equine parasites, deworming, and horse health. We appreciate your business, and want to help you keep your horses healthy and their worms under control. If there's a topic you'd like us to write about or a question you'd like to have answered, please email us at hlab@horsemenslab.com.
Sincerely,
John W. Byrd, DVM
Horsemen's Laboratory
|
|
Equine Parasite Resistance...A Hot Topic
Equine
parasite resistance is becoming a growing problem, with worms (including
strongyles) becoming less sensitive to anthelmintics, the drugs that expel
parasitic worms (helminths).It's a serious enough issue that several recent
parasitology conferences made it a primary topic. How does it affect you and
your deworming options? It depends on what you use, and how you deworm.
Basically,
when a dewormer is given to a horse, it kills off the active adult worm
population. However, some adults that weren't affected by that dose could
survive, and their genes will be the ones passed on to the next generation. In
the case of small strongyles (see Worm of the Month sidebar), there can even be larvae
encysted in the horse's intestines that will erupt and mature to take the place
of those adults that have died, often causing inflammation, diarrhea, and
sometimes colic. Although this is a very simplistic explanation, it shows that
frequent deworming to keep a horse totally parasite-free is not only
unrealistic, it can be harmful. If that's the case, what do we do now?
John Byrd,
DVM, founder of Horsemen's Laboratory (H-Lab), was recently interviewed for several
publications (see links, below) on his views about equine parasite resistance.
The type of fecal exams offered by H-Lab since the early 1990s are just the
kind of assessments now suggested by equine parasitologists in the revised
deworming protocols.
The new
deworming recommendations include:
-
Running
fecal exams to determine individual horse parasite burdens, and types of worms
that are present.
- Focusing
on 'high shedding' horses that produce higher egg counts, and deworm them more
frequently than low-shedders, to reduce the numbers of eggs in your
environment.
-
Use a
dewormer suited to your parasite population, and don't leap to rotation as a
panacea; rotating dewormers can mask what's actually going on.
Confused? Don't be. If you're already using Horsemen's Laboratory to assess your horse's
worm infestation, you're on the right track. Below are some links to the
articles Dr. Byrd was interviewed for; they'll provide a good overview of the
issues. We'll continue to look at this issue, and the latest developments, in Worm
Control News. And as always, if you have questions, please feel free to contact
us!
Holistic Horse E-News - August, 2009
Holistic Horse E-News - August, 2009 (tips)
Veterinary Practice News - October, 2009
|
|
About Horsemen's Lab
In this
section of Worm Control News we'll introduce you to the people at H-Lab, explain
what we do behind the scenes, and highlight actual customers and their worm
control strategies.
Located in
Mahomet, Ill., Horsemen's Laboratory does equine fecal exams by mail, serving
clients in the U.S. and Canada since 1992. H-Lab founder John Byrd, DVM,
started the organization in response to the daily deworming medications that
came onto the market in 1992, while he was in private equine veterinary
practice.
"Although I
had clients coming to me and asking for it, I thought deworming daily was
excessive. So I started Horsemen's Laboratory, with the idea that it was
healthier for the horse, and more economical for the owner, to actually know
when, and if, a horse needed to be dewormed," says Dr. Byrd. Even he was
surprised by the findings once he started running the fecal samples. "I was
seeing fewer than one in 10 horses with eggs in their stools," he reports.
The Daily Routine
A typical
day at H-Lab involves checking the mail, preparing and running that day's
samples, and following up with clients. Managing the office is Dr. Byrd's wife
of 44 years, Becky Byrd. She was Dr. Byrd's right hand during his years in
private equine practice, and is the person you're most likely to speak with if
you call the office.
As for the
lab, there's a lot of horse poop going under Dr. Byrd's microscope these days.
"Right now we perform over 2,500 fecal egg counts annually," he says. Many of H-Lab's clients are in horse-dense states such as
California, Illinois, Florida, and Texas, but they also serve clients from
coast to coast in the U.S., and even Canada. "We have clients in Nova Scotia,
and in British Columbia," says Dr. Byrd.
For The Health Of The Horse
H-Lab's
mission is to help owners evaluate their horses' worm control programs, and
deworm efficiently and economically. Dr. Byrd says it's better for the horse,
and in ways you might not think of. "It's been proven that worms have an
adverse effect on a horse's health, and I've come across empirical evidence
that it can also affect their performance for up to several weeks afterward,"
he says.
According
to some of his veterinary colleagues, when daily and paste dewormers came into
the market, they started seeing a noticeable decline in performance for
endurance horses in training that were under their care; since these horses had their pulse and
respiration checked and recorded frequently, a drop-off was noticeable, as
opposed to simply feeling the horse was 'off.' "This hasn't been corroborated
by studies that I know of, but it's based in common sense, and certainly I feel
it's better to deworm a horse only as often as is needed," says Dr. Byrd.
In Conclusion...
Equine parasite resistance is becoming a serious
issue worldwide, and equine parasitologists are now recommending fecal exams
along with targeted deworming to maintain 'dewormer sensitive' parasite
populations. For more details on this issue, see Equine Parasite Resistance...A Hot Topic (above), and watch future issues of Worm Control News for updates.
___________________________
Here at Horsemen's Laboratory, we're happy to support horse owners who want to have healthier, happier horses
and manage their barns, pastures, and paddocks appropriately. If you have
questions, please email us at hlab@horsemenslab.com or call our toll-free
lab phone at 800-544-0599.
|
Thanks!
We hope you've enjoyed reading our inaugural issue of Worm Control News. If you have any comments or suggestions, please pass them along. Our email address is hlab@horsemenslab.com.
|
|
|
|
|
|
|
|
Buy 6, Get 1 Free!
|
Save $$$ - When you pre-pay for 6 (or more) fecal sample tests by January 1, 2010, you'll get one test free!*
Whether you have one horse or many, buying in bulk saves money:
1 fecal sample = $15 per sample
2-5 fecal samples = $13 per sample
6+ fecal samples = $11 per sample
And now, you'll get an extra bonus - a free test! - when you buy at least six.
How It Works:
A 'credit' for the number of tests purchased (plus any free tests) goes onto your account in our records. We'll
send you a collection kit either when your horse is due to be tested, after he has a positive result that requires testing after deworming, or any time you request
one, so there's no need to store collection kits and wonder why you can't find one when
you need one. We'll always email you a reminder (or send you a collection kit, if you've paid in advance) when it's time for a test!
Order Worm Testing Kits Here:
For our customers' convenience, we take
Visa, Mastercard, American Express, and PayPal for ONLINE orders; for phone orders, we accept Visa and Mastercard.
Thank you for your business!
|
*Offer Expires January 1, 2010
*Maximum four free tests per account
|
|
|
|
