YH 454 combined pdf

august 2019 Your Horse ISSUE 454
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August 2019
(Issue 454)
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Contents
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See page 94
REGULARS
6 Your Horse challenges you…
to try horse football
8 Horse talk Things you need to
know about in the equine world
10 #Hack1000miles Test your road
riding knowledge — and stay safe
16 Horses around the world
The Caspian Horse
22 Work–horse balance The equine
nutritionist
30 Your say You get in touch
32 Send a selfie You share your pics
130 Take five with CBBC vet
James Greenwood
Your horse’s
TRAINING
36 Breaking the mould Ros Canter’s
genius gymnastic exercises
44 Competition confidence
Declutter your mind and rid yourself
of crippling nerves
48 Loosen up Three easy ways to
improve your horse’s suppleness
50 Sharper reactions Event rider Tom
Rowland shows you how to improve
your horse’s course-jumping skills
56 Powerful
steps
Former
Spanish Riding
School rider
Florian Bacher
sets you on
the right path
to achieve
collection
features
18 Interview Dressage rider Jo Barry
talks openly about her return to riding
following a devastating head injury
24 Plastic pollution What you can
do — and what the equine world is
doing — to save the planet
24
Reuse
and recycle
your plastic
Your horse’s
CARE
70 One-eyed wonders Discover how
well horses cope if they lose an eye
76 Lovely legs Katie Jerram-Hunnable
shows you how to trim your horse’s
legs for a show-winning finish
78 Summertime woes The health
issues pesky flies cause and how
to treat them
80 The less than perfect hoof
All about the vital role hoof balance
plays in keeping your horse sound
86 Wound care Supergroom Alan
Davies shows you how to manage
wounds for effective healing
88 The endocrine system
Understand how hormones help
your horse stay healthy
50
Push your boundaries
at home, with
Tom Rowland’s
quirky course
65
44
On the cover
10
124
ask The
experts
98 Planning & law Field shelters
• Grazing rights • Building new stables
100 Hydrotherapy What to expect
when you go swimming • Better
fitness • Benefits of a water treadmill
102 Using studs The types of studs
you may need • Tools for your stud
kit • How to avoid stud injuries
104 Equine careers Job options in
the horse world • Becoming a trainer
• Careers in nutrition
106 Advice from Spillers Monitoring
your horse’s weight
Your horse’s
GEAR and yours
112 What’s new? The latest products
to hit the shops this month
114 Big test Which fly mask came out
on top in our review?
118 On trend Six of the best tendon
boots on the market
120 Buyer’s guide What to look for
when choosing a competition jacket
124 Protective boots Should boots
that claim to protect your horse’s legs
have to meet a safety standard?
120
to Win in this issue
65 Tack and other kit
from Amerigo
110 Rugs, therapy
products and more
110
WORTH
£1000
65
24
56
36
124
80
114
4 your horse august 2019
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august 2019 your horse 5

horse talk
horse
Here’s what you need to
know about this month
talk
HORSES IN ART
The Lifeboat Horse can be
seen on the north Norfolk coast
This month
we love...
Three things from the equestrian
world that caught our eye
learn from the stars
See Charlotte in action at Your Horse Live
On 8-10 November, at Stoneleigh Park,
Warwickshire, British dressage superstar
Charlotte Dujardin will be demonstrating
her skills at Your Horse Live 2019.
A triple gold medallist at the London
2012 and Rio 2016 Olympic Games,
Charlotte is also a former European
Champion, World Champion and holds all
three world records in dressage.
On Friday 8 November, she’ll be sharing
her secret training tips for Olympic success.
On Saturday and Sunday, Charlotte will
show us why she’s the queen of dressage
with some of her top horses.
On Friday, the main arena will be taken
over by the very best trainers in the UK.
There’s truly something here for everyone,
to be inspired, amazed and informed with
our masterclasses covering dressage,
showjumping, eventing and showing.
Friday’s schedule also includes the SEIB
Search for a Star Mountain & Moorland
championship, while Saturday and Sunday
will showcase incredible displays from
world-class performers. Plus, you can shop
every day at the UK’s biggest equestrian
shopping event, with hundreds of
tradestands and great bargains on offer.
Don’t miss out! Buy your tickets today at
yourhorselive.co.uk.
BEFORE
Ollie was badly
mistreated by his
previous owners and is
very wary of humans
after
Ollie is happily living
out his days with his
friends at Hoofbeats
Rescue Update
Ever wondered what happens to
the rescued horses and ponies
you read about in the news?
Wonder no more…
Thirteen years ago, Ollie arrived at
Hoofbeats Equine Rehabilitation
Sanctuary near Plymouth. Initially
purchased as an unhandled youngster
Charlotte Dujardin
will share her training
tips for dressage
success on Friday
from a horse sale, Ollie became
uncomfortable with a headcollar during
his early training and subsequently had
his head tied to his feet. Consequently,
it’s no surprise he became extremely
fearful of humans and appeared on TV’s
Britain’s Worst Pets for his behaviour
before he came to Hoofbeats in 2006.
Sharon Vieira, Hoofbeats’ founder, says:
“Ollie has the most upsetting past that
we know of of any of our horses, and
he’s also our most troubled.”
Now, as one of the sanctuary’s longest
inhabitants, Ollie is a permanent Hoofbeats
resident. Living naturally within a peaceful
herd, he’s worked with only on his own
terms and often at liberty.
While this sweet boy will greet humans
for the odd treat or two, Hoofbeats
allows Ollie to “just be a horse”, living out
his days among his field friends.
Photo: your horse live
Sculpture given permanent home
A horse sculpture in the sea that’s revealed
by changing tides has become a permanent
attraction on the north Norfolk coast after
local residents raised £15,000 to buy it.
The Lifeboat Horse by artist Rachael Long
has found a harbour home at Wells-nextthe-Sea.
The 3m-high sculpture celebrates
the work of horses that used to tow the
BANNED SUBSTANCES
FEI warns of
synephrine in
your horse’s
environment
The FEI is warning the equestrian
community about synephrine, which is
a banned substance listed on the Equine
Prohibited Substances List.
A high number of samples taken from
horses under the Equine Anti-Doping
and Controlled Medication Programme
have tested positive for the substance.
Investigations into the source responsible
for the positive cases are continuing, but
the FEI is warning that synephrine can
be found in every horse’s environment.
town’s lifeboat out to sea in the 1800s.
Locals took it to their hearts when it was
installed for a temporary art trail in 2018
and wanted to ensure it had a forever home.
“In a very short time, it’s become part of
the seascape and it’s a fitting tribute to our
local history. It’s great to see it back,” said
Wells harbour master Robert Smith.
Synephrine has been
detected in certain
types of hay
Synephrine is a stimulant that can cause
vasoconstriction — an increased heart rate
— and is used as a weight loss aid.
In certain parts of the world, it can be
found in plants such as common rush and
the leaves of citrus trees. Synephrine has
also been detected in Teff grass hay.
It is an ingredient in some herbal and
nutritional supplements, and commonly
found in the peel extract of Seville orange,
which is used as a flavouring agent.
FRACTURE RESEARCH
Scientists pave the
way to aid fracture repair in horses
The Animal Health Trust (AHT) and the University of East Anglia
have succeeded in producing 3D-printed scaffolds that could
be used to turn stem cells into bone in the laboratory.
Bone fractures in horses usually occur as a result of traumatic
injuries or bone overloading. Severe fractures are difficult to treat
because of a horse’s need to bear weight on all of his limbs. Bone
grafting is often carried out in human patients, but
this technique is not commonly used in horses.
The scaffold material is inexpensive and can be
printed to any size or shape. Once formed,
it’s then treated to encourage the
attachment of cells to its surface.
Dr Debbie Guest, head of
stem cell research at AHT, said:
“This work paves the way
towards laboratory production
of bone constructs that could
be used to aid fracture repair.
It could ultimately benefit many
horses in the future.”
Perfectly organised
What better way to make sure you get
those #Hack1000miles rides into your
busy schedule than with the Ponies
Desktop Weekly Planner by Thelwell.
RRP £9.99 amazon.co.uk
IT’s a VEt’s Life
Julian Norton, star of Channel 5 TV
series The Yorkshire Vet, relays some
of the highs and lows he faces daily
in his working (and personal) life.
Horses, Heifers and Hairy Pigs: The
Life of a Yorkshire Vet is a warm and
often very funny memoir.
RRP £5.89 (paperback) amazon.co.uk
Party time
Buying a gift for a horsey friend? The
perfect wrapping paper for a horse
lover, this design features watercolour
illustrations of partying horses. Includes
two sheets of paper and two tags.
RRP £4.45 amazon.co.uk
8 your horse august 2019 www.yourhorse.co.uk
august 2019 your horse 9

vet notes l fighting flies
notes
vet
What you’ll learn:
l The different types of fly
l How they affect your horse
l Management tips
Flying
nuisance
The warmth of summer brings with it pesky flies
and biting insects. Leona Bramell MRCVS
discusses the common problems they can cause
After a cold or wet winter,
most horse riders welcome
the onset of summer, but one
downside to the longer days
and warmer weather is the
arrival of flies. Some horses are more
adversely affected by these insects than
others, so knowing how to reduce and
manage fly irritation will help your horse
stay happy and fly-free this summer.
As well as being
annoying, flies can cause
a range of health issues
Photo: Oscity/Shutterstock
meet the expert
Leona Bramall CertAVP(EM)
MVB MRCVS is an equine vet at
Gillivervet Ltd in Lancashire. She
holds an advanced veterinary
practitioner certificate in equine
medicine and her primary areas of
interest lie in dermatology and gastrointestinal
disease. Visit www.gillivervet.co.uk/vets.aspx
Sweet itch
Sweet itch is caused by an allergic
reaction to the saliva of the Culicoides
biting midge. Affected horses
develop itching of the mane and tail
and, in some cases, the face and poll.
Itching begins in summer, but for
some horses sweet itch can be a
year-round problem. The level of
severity varies; while some horses
itch themselves bald, others may
develop ulceration or secondary
bacterial infections.
Precautionary measures
Prevention is based on reducing
exposure to the offending midges.
If at all possible, avoid fields with
stagnant water or those adjacent to
woodland areas that inherently have
high midge populations. Horses
affected with sweet itch should be
stabled at dawn and dusk when the
midges are most active. Fans may
deter midges from entering stables.
Sweet itch fly masks and rugs also
play an integral role in prevention, as
do fly and insect repellents, although
the effectiveness of these varies.
Veterinary intervention
Contact your veterinary surgeon if
itching continues despite using the
above preventative measures, if skin
is hot and inflamed, or if you’re
concerned about possible infection.
Your vet will examine your horse and
may prescribe injectable, oral and/or
topical (cream) medications.
Insect hypersensitivity
In addition to sweet itch, some horses can
develop skin lumps (urticaria), with or
without associated itching secondary to
other flies and insects. Severity varies, from
a small lump at the site of contact to an
extensive hypersensitive response.
Stick ‘em up
If your horse is stabled during the day,
ensure his stable is kept as clean as possible
to reduce the number of flies in the stable
environment. You can also spray the stable
with fly repellents, but don’t spray directly
near water or feed buckets.
If the lumps are extensive, don’t appear
to be resolving, or make your horse itch,
seek advice from your veterinary surgeon.
Contact your vet
if lumps become
itchy or don’t
resolve on their own
Sweet itch fly
masks and rugs
help reduce
exposure to
midges
Lumps on your horse’s
skin can indicate a
hypersensitive response
Photo: Bauer library
Photos: Leona Bramall
Horse flies are
persistent and
extremely annoying
Photo: Bauer library
The main enemies
1 Horse flies
No doubt we’re all more than familiar with
horse flies (Tabanus spp.). Normally, there is
one generation of adult flies per year, which
emerge in early summer. Peak feeding
activity occurs on warm, humid days in July
and August. Horse flies are generally
persistent in their attempts to feed and are
therefore a source of great annoyance.
2 Bot flies
Bot flies (Gasterophilus spp.) are bee-like in
appearance and generally active for a
number of weeks in late summer. They can
cause immense irritation and distress when
laying their eggs — generally on the skin and
coat of your horse’s limbs and, occasionally,
around the lips and under his chin.
Check his coat
Bot eggs are normally easy to spot and are
visible as white or cream-coloured eggs,
about 1-2mm in length. They are firmly
attached to the hair, but can be removed
using a commercial bot egg knife. If bot eggs
are noted during the preceding year, your
horse should be wormed with an ivermectinbased
wormer after the first winter frost.
Prevention
At times of peak fly activity, especially
when bot flies are out, consider
stabling your horse during the day and
turning him out at night. Fly masks,
rugs and insect repellents may help too.
Sarcoids
These are arguably the most prevalent form
of skin tumour in non-grey horses. They are
believed to be caused by a strain of bovine
papilloma virus and transmitted by flies, so
summer is a key time for spread. Fly control
plays an integral role in preventing and
reducing sarcoids.
It is likely that individual horses have a
genetic predisposition for the disease.
Sarcoids can occur at any location on the
skin, but the most commonly affected areas
are those prone to sweating — which, in turn,
attract flies — such as the armpits, inside of
the hindlimbs and, in geldings, the sheath.
Spotting the signs
There are six different types of sarcoid, so if
you notice any skin masses or lesions on
your horse that you’re concerned about, seek
advice from your veterinary surgeon.
Sarcoids can occur
anywhere on the
horse’s body
Sarcoids are skin tumours, so early
detection and treatment as advised by your
veterinary surgeon is very important. Early
intervention enables the sarcoid to be
treated before it increases further in size and
reduces the chance of spread and further
lesions developing. The treatment
recommended by your vet will depend on
the type of sarcoid and its location.
Photo: Leona Bramall
Fly strike
Although not a pleasant thought,
open wounds can sometimes be
subject to fly strike, whereby green
and bluebottle flies feed and lay their
eggs, with the fly larvae/maggots
hatching three or four days later.
To prevent this, open wounds
should be managed appropriately
by keeping them clean and covered
(see Managing wounds, p74) and fly
control measures should be used.
If you notice a larval-infested
wound, contact your veterinary
surgeon. They will likely advise
hosing the wound and subsequently
cleaning it with a disinfectant. The
vet will generally visit and administer
an injection against the larvae.
78 your horse august 2019 www.yourhorse.co.uk www.yourhorse.co.uk
august 2019 your horse 79

Your horse’s care
Control
centre
Hormones do a lot more than make your mare
moody. Vet Claire Dixon MRCVS explains how the
endocrine system works and what can go wrong
Photos: Bauer Library, unless stated
out
Horses
inside
horses insIde out l endocrine system
meet the
expert
Claire Dixon
MRCVS is a clinician
in equine medicine
at the University of
Glasgow, splitting her
time between working in the
hospital and teaching students.
Prior to this, she worked at
Tufts University (USA),
initially as a resident in
large animal internal
medicine, followed by
a period as an
emergency clinician.
While you probably
associate hormones
with mood swings
and mareish
behaviour, there are
many other functions that fall under the
regulation of the body’s most vital control
centre — the endocrine system.
The horse’s endocrine system is the
collection of glands that produce hormones
which regulate a number of vital functions.
In order for the body to respond and adapt
to changes, both internally and externally,
the various functions and processes must be
controlled in a co-ordinated fashion.
The endocrine system is part of this, and
involves hormones being produced by
specific tissues that then travel through the
blood to exert their influence in a variety of
ways. Some of these hormones, such as
adrenaline, have an instant effect; others
operate more slowly. Often, there are pairs of
hormones with complementary functions.
Calcitonin, for example, decreases blood
calcium levels, whereas parathyroid
increases them. This combination allows
a faster response and a greater degree of
control and fine tuning over the body.
The pituitary gland
in the brain helps
with a number of
foaling functions
Parathyroid
glands
Adrenal
glands
Thyroid
gland
Pituitary
gland
Hormones
in a nutshell
There are a large number of
hormones, each exerting a very
different effect on different tissues
and organs. Hormones control
everything from growth and
development (for example, replacing
old, worn out cells), lactation,
metabolism, fluid balance, blood
pressure, the “fight or flight”
response and digestion of food.
In fact, there is very little that
isn’t related in some way to
the endocrine system.
Pancreas
Ovaries
(female)
Testes
(male)
Hormones’ six homes
The endocrine system encompasses most of
the organs of the body, with hormones
secreted from the stomach and intestines to
regulate digestion, and even from fat (leptin,
which inhibits appetite). While some
hormones work only on a specific tissue,
others exert their effect over the whole body.
Most hormones are secreted from the
following six structures (see diagram, left):
Pituitary gland The pituitary gland sits
at the base of the brain. It works closely
with the hypothalamus, just next to it, to
regulate a number of functions.
It is divided into three parts, the pars
distalis, pars intermedia and pars nervosa.
The pars distalis contains a number of cells,
which each produce a different hormone
Antidiuretic
hormone helps
to maintain
hydration
with a different function:
n Growth hormone, which promotes growth
over the entire body.
n Follicle stimulating hormone (FSH) and
luteinising hormone (LH), which control
the reproductive activities of the ovaries
and testes.
n Prolactin, involved in milk production.
Adrenocorticotropin hormone (ACTH) is
produced from the pars intermedia. ACTH is
probably the best known of the equine
hormones, as it is increased in horses with
pituitary pars intermedia dysfunction (PPID
— Cushing’s) and testing the level of ACTH in
the blood is used for diagnosis. In normal
horses, ACTH controls the adrenal gland.
The pars nervosa produces the antidiuretic
hormone, which controls the amount of
urine production, helping to maintain
hydration when water intake is decreased.
It also produces the hormone oxytocin,
which is involved in lactation and foaling.
88 your horse August 2019 www.yourhorse.co.uk www.yourhorse.co.uk
August 2019 your horse 89

Your horse’s care
horses insIde out l endocrine system
Thyroid hormones are
involved in many
metabolic and
growth processes in
all types of horses
Parathyroid gland In many species of
animals, the parathyroid glands are tiny
glands located next to the thyroid glands
on each side of the neck — if you can find
the thyroid gland, you can find the
parathyroid. In horses, however, there are
four parathyroid glands — two upper glands
located anywhere around the thyroid glands,
and two lower glands, which may be
anywhere along the jugular groove from the
jaw to the shoulder (and, indeed, even just
inside the chest cavity).
This variability makes it very difficult to
locate the normal parathyroid glands in the
horse. However, there are techniques to
locate the glands when they are abnormal.
The parathyroid produces parathyroid
hormone from chief cells, which regulates
calcium levels by increasing the blood
calcium concentration. If calcium levels drop,
then parathyroid hormone levels increase,
and the body removes calcium from bones,
absorbs more from the intestines and
excretes less in urine, resulting in increased
blood calcium levels. This is partly due to the
parathyroid hormone leading to increased
levels of active vitamin D.
This is a really important function, as
calcium is vitally important for muscle
contraction (with the most important muscle
being the heart). When the calcium levels
rise again, the amount of parathyroid
hormone produced decreases.
Sex organs The main hormone produced
by the male testes is testosterone, which
is responsible for the distinguishing
characteristics of the masculine body.
Many of the results of this will be very
familiar to anyone who has worked with
stallions, but some of the effects are less
obvious. For example, testosterone also
leads to an increase in the number of red
blood cells present in the blood.
The female ovarian hormones are
oestrogen and progesterone and are involved
in the normal reproductive cycle of the mare.
Pancreas The pancreas lies next to the
first part of the small intestine and serves
two major functions. First, to secrete
digestive enzymes into the small intestine,
and second, to produce two important
hormones — insulin and glucagon — which
regulate glucose, lipid and protein
metabolism. Insulin is more commonly
measured and talked about in horses, due
to the fact that high levels of insulin lead
to the development of laminitis.
Obese horses with hyperinsulinaemia and
laminitis have a disease termed equine
metabolic syndrome (EMS). Insulin promotes
Adrenaline is released
as part of the ‘fight
or flight’ response
the uptake of glucose into cells, but in horses
with EMS, the cells stop responding to
insulin (insulin dysregulation), resulting in
increased production of insulin.
“The two hormones
produced by the thyroid gland
increase the metabolic rate”
Adrenal gland The adrenal gland sits
just next to the kidneys and consists of
two distinct parts — the adrenal medulla
and the adrenal cortex. The adrenal
medulla is the central part, which is
involved in the “fight or flight” stress
response by producing adrenaline. Around
this is the adrenal cortex, which produces
various corticosteroids.
Corticosteroids are involved in electrolyte
balance (primarily sodium and potassium)
and metabolism of carbohydrates, proteins
and fats. Small amounts of androgenic
hormones are produced that exhibit the
same effects on the body as the male sex
hormone testosterone.
Thyroid gland The thyroid glands are
located on either side of the windpipe,
just behind the horse’s larynx. They
secrete two hormones, thyroxine and
triiodothyronine (commonly referred to as
T4 and T3 respectively) under the control of
the pituitary gland. These hormones
increase metabolic rate and are therefore
involved in a large number of metabolic and
growth processes. They are especially
important in the growth of foals, with levels
being much higher in foals up to three to
four months of age and declining in adults.
The thyroid gland is also involved in
calcium regulation via the hormone
calcitonin, which decreases calcium levels.
The pancreas is important
for your horse’s metabolism
and the regulation of
insulin levels when eating
Playing a part in laminitis
Our understanding of endocrinopathic
laminitis has grown substantially in
recent years. We know the majority of
laminitis cases are caused by either
Pituitary Pars Intermedia Dysfunction
(PPID) or equine metabolic syndrome
(EMS). PPID occurs due to enlargement
of the pars intermedia portion of the
pituitary gland, and results in increased
levels of the hormone ACTH. Clinical
signs include weight loss, a longer coat,
increased drinking and urination,
sweating, lethargy and laminitis.
Diagnosis
Diagnosis involves blood testing for
ACTH levels, either at baseline, or
following the administration of a
hormone to stimulate the pituitary
gland (TRH stimulation test).
Treatment with pergolide results
in decreased ACTH levels and
improvement, or resolution of clinical
signs. Each horse will require a different
dose, so usual practice is to start
treatment at a low dose and gradually
increase if blood tests show ACTH
levels remain high.
EMS involves the presence of obesity
(or regional adiposity), peripheral insulin
resistance or dysregulation, and an
increased risk (or presence) of laminitis.
Diagnosis is based on identifying these
three factors and so requires blood
testing to demonstrate increased insulin
levels, or increased insulin in response to
feed/sugar challenge.
Treatment
Treatment centres on achieving weight
loss and increasing exercise, as this is the
best way to improve insulin sensitivity.
However, in horses and ponies with
active laminitis, the requirement for rest
rules out exercise. This is when we may
reach for medical therapy to assist us,
until exercise can resume.
Medications used include metformin
(which improves peripheral insulin
sensitivity in humans and decreases
intestinal absorption of glucose in horses),
or levothyrozine (which acts as thyroid
hormones do to increase metabolic rate).
In horses with
active laminitis, the
requirement for rest
rules out exercise
90 your horse August 2019 www.yourhorse.co.uk www.yourhorse.co.uk
August 2019 your horse 91

Your horse’s care
-
Endocrine
upsets
When parts of the endocrine system fail
to work properly, it can cause:
Hypothyroidism is rare in adult horses,
despite many conditions such as obesity,
laminitis and insulin resistance being
attributed to low concentrations of thyroid
hormone. However, it may occur in foals
born to mares who are fed inappropriate
amounts of iodine during pregnancy.
Thyroid adenoma You may have noticed
that some older horses have thyroid
glands that are very easy to feel. This is
due to benign enlargement, which is really
common and nothing to worry about.
Pheochromocytoma This is a very rare
type of tumour arising from the adrenal
medulla. Some of these tumours will be
‘functional’, which means they continue to
produce adrenaline. The signs seen in horses
therefore mimic situations where high levels
of adrenaline are produced. Horses may have
a high heart rate, increased breathing rate,
anxiety, profuse sweating, dilated pupils,
colic due to reduced intestinal motility and
high blood sugar. While surgery to remove
the adrenal gland would often be curative,
the complexity of the surgery means that
euthanasia is the more likely outcome.
Primary hyperparathyroidism This occurs
when the chief cells in the parathyroid
secrete excessive amounts of parathyroid
hormone and no longer respond to the
negative feedback of calcium. The
increased secretion is due to growth of a
parathyroid adenoma, or parathyroid
hyperplasia (over-growth of the gland). This
results in increased blood calcium levels
and, as this involves removing calcium from
bones, the bones suffer as a consequence.
Some older horses have
enlarged thyroid glands,
but generally this is
nothing to worry about
The bones of the face may become swollen,
resulting in what’s known as ‘big head’ or
‘rubber jaw’. Calcium removal from the long
bones can lead to lameness, or even the risk
of spontaneous fracture. Other signs include
weight loss, lack of appetite, lethargy and colic.
Diagnosis is via blood tests and the main
treatment, which is curative, is removal of
the enlarged parathyroid. However, as
mentioned, finding the parathyroid, even
when enlarged, is difficult. The best way to
find it is through a nuclear scintigraphy scan
to highlight the area of the neck where the
parathyroid is located. Once this area is
“Ovarian tumours
may lead to stallionlike
behaviour or
persistent oestrus”
Excessive calcium
in the blood can
result in lameness or
spontaneous fractures
narrowed down, the exact location can be
pinpointed using ultrasonography. At this
point, surgical removal may be possible.
Ovarian tumour Granulosa cell tumours
are the most common tumours of the
reproductive tract of the mare. They can
occur in mares of any age and may lead to
behavioural changes, with either stallion-like
behaviour or persistent oestrus/anoestrus.
In other cases, behaviour is normal, but
colic signs may occur. Diagnosis is based on
blood testing for hormone levels, alongside
palpation of the ovary per rectum and
ultrasonography. Once the abnormal ovary is
identified, it can be surgically removed, with
a good prognosis. Surgery is most commonly
performed laparoscopically (keyhole
surgery) under standing sedation.
92 your horse August 2019 www.yourhorse.co.uk