2018
SEMINAR NOTES
THOROUGHBRED BREEDERS SEMINAR
Hunter Valley Equine Research Centre
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TABLE OF CONTENTS SCHEDULE OF LECTURES
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LECTURES Lecture 1: STALLION PHYSIOLOGY
5-14
Lecture 2: BROODMARE PHYSIOLOGY
15-20
Lecture 3: THE DIFFICULT BREEDER
21-22
Lecture 4: INTERNAL PARASITES
23-30
Lecture 5: NUTRITION & PASTURES - feeding in drought
31-67
Lecture 6: NEWBORN FOALS
68-78
Lecture 7: MANAGING PRE-TERM LOSSES IN MARES
79-95
Lecture 8: BIOSECURITY - Psittacosis from horses, what’s the risk?
96-98
Applying OneHealth surveillance to emerging zoonoses. Lecture 9: FOAL FARRIERY - therapeutic
99-120
Lecture 10: SCOPING, X-RAYS & SURGERY
121-132
Lecture 11: NUTRITION - yearling preparation
133-134
© August 2018 Thoroughbred Breeders Seminar The Thoroughbred Breeders NSW, Hunter Thoroughbred Breeders and the Hunter Valley Equine Research Centre does not guarantee that this publication is without flaw and do not accept any liability whatsoever for any errors, defects or omissions in the information provided.
Hunter Valley Equine Research Centre
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Schedule of lectures
DAY 1: Monday 13th August 2018 Time
Session detail
8.30am
Arrival registration, coffee and introduction
9.30 – 10.30am
Lecture 1:
10.30 – 11.00am
Morning Tea Break – in front foyer
11.00 – 12.00pm
Lecture 2:
12.00 – 1.00pm
Lecture 3:
1.00 – 2.30pm
Lunch Break – in front foyer
Thanks to “The Hunted Gourmet”
2.30 – 3.30pm
Lecture 4:
Dr Peter Carrigan BVSc BVMS Mr Chris Lawlor Managing Director – International Animal Health Products
3.30 – 4.00pm
Afternoon Tea Break – in front foyer
4.00 – 5.00pm
Lecture 5:
STALLION PHYSIOLOGY
BROODMARE PHYSIOLOGY
THE DIFFICULT BREEDER
INTERNAL PARASITES (Including Bio Worma)
NUTRITION & PASTURES (Feeding in drought)
5.00pm
Lecture room closed
5.00 – 6.30pm
Light supper and drinks evening – in front foyer An opportunity for all to speak with lecturers and 'Special Guest Speaker'
Hunter Valley Equine Research Centre
Speaker
Dr Jim Rodger BVMs MRCVSc FACVSc
Dr Sean Finan MVB DACT Dr Wendy Perriam BSc.,BVMS(hons).,MANZCVSc (Eq.Med.),CMAVA.
Dr Peter Huntington BVSc MACVSc Mr Ross Watson Agronomist – Ross Watson Agriculture
Dinner thanks to our sponsors “The Hunted Gourmet” Dr Natasha Hamilton Racing Australia Equine Genetics Research Centre
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Gastrointestinal Parasite Management on Stud Farms
Historically, gastrointestinal (GI) parasite management on stud farms has been based on whole-herd dosing at set 6 to 8 week intervals, with seasonal rotation of the drench class. These protocols were very successful in controlling GI parasites, but have led to: 1. the development of SIGNIFICANT drench resistance in GI parasites, 2. a change in the disease-causing parasite population of the horse (move from large strongyles, to now small strongyles in adults and ascarids in juveniles), Further points to consider with regards to GI parasite management: a) Development of new drench classes is MINIMAL to NON-EXISTENT – with no new class having reached the equine market for over 25 years. Despite the wide selection of pastes and formulations on the market, there are only actually a small selection of drench classes available to us: b) CLASS RESISTANCE PATTERNS BZ’s
oxfenbendazole, fenbendazole
widespread small strongyle resistance
avermectins (ivermectin, abamectin) and milbemycins (moxidectin)
widespread ascarid resistance
(benzimidazoles) ML’s (macrocyclic lactones) THP’s
pyrantel and morantel salts
(tetrahydropyrimidines) HC’s
piperazine
(heterocyclic compounds) IP’s (isoquinoline-pyrozines)
praziquantel
effective against tapeworm
c) Our understanding of GI parasite spread in horse populations has evolved - around 20% of horses in a population shed 80% of the worm eggs on a pasture d) Parasite free horses are not possible NOR desirable - the goal should instead be to minimise parasite egg contamination of pasture e) We need to save REFUGIA – the subpopulation of GI parasites that escape exposure or challenge from a drench, and therefore by not exposing all GI parasites in the horse population to a drench, we maintain the drench susceptibility in the parasite population.
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It is important to note that the following recommendations only apply to horses 3 years of age or greater. This brings us to strategic drenching – a concept that attempts to find a balance between minimising the risk of parasitic infections in horses, control parasite egg contamination of the environment, but also prevent the development of drench resistance.
It involves a targeted approach to GI parasites at an individual horse level, by identifying HIGH worm egg shedding horses through Faecal Egg Counting (FEC’s) and treating just those individuals. This reduces our use of drenches by up to 80% - a financial saving, but also maintains REFUGIA, because by not drenching the LOW and MODERATE worm egg shedding horses, we are not exposing the GI parasites in these horses to a drench, thereby maintaining drench susceptibility in a parasite population.
NOTES………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… …………………………………………………………………………………………………………
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Table 1: Parameters of a newborn foal. Normal newborn foal
Abnormal newborn foal Bright red
Mucous membranes
Pink and moist
Purple or yellow tinge Small haemorrhages Laboured respiration
Respiration
Regular. 60-80 breaths/min at birth. Decreases to 20 - 40 breaths/min within 1 hour of birth.
Exaggerated chest and abdominal movement Nostril flaring with breaths
Heart rate
Temperature
Activity
80-100 beats/min after birth. Can increase to 150 beats/min with struggling and attempts to stand.
Irregular Low >120 bpm
37.2- 38.5oC
> 38.5oC
Not reliable indicator of infection
< 37.2oC
Sitting sternal after few minutes
Not sitting sternal after birth
Standing and nursing within 2 hrs
Not standing/nursing within 3 hrs Bleeding
Umbilicus
White, moist in new born
Extremities
Warm
Cold
Urinate within 12hrs of birth
Straining to urinate
Urination
Leaking urine
Discoloured urine
NOTES………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… Common diseases of foals in the first month of life There are unfortunately many diseases that a young foal can succumb to in the early neonatal period. The most common diseases which are encountered are Neonatal Syndrome, sepsis, prematurity, neonatal isoerythrolysis and diarrhoea. These diseases are outlined below.
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Neonatal Syndrome Over the years, many terms have been used to describe foals with Neonatal Syndrome including dummy foal syndrome, perinatal asphyxia syndrome (PAS), and hypoxic ischaemic encephalopathy. Most of these foals are initially normal at birth, but subsequently show abnormal clinical signs within the first 48 hours of life. Neonatal Syndrome is one of the most common reasons for referral of a foal to an intensive care unit. The exact cause of Neonatal Syndrome in foals is not known but multiple risk factors for the development of Neonatal Syndrome have been described and are summarised in Table 2. In some foals with Neonatal Syndrome, an uneventful foaling is observed and no risk factor can be recognised. It is thought that the foals experience a combination of hypoxia (inadequate oxygen supply) and ischaemia (insufficient blood supply) to the brain and other critical organ systems.
Table 2: Risk factors associated with Neonatal Syndrome Predisposing factors:
Examples:
Severe maternal illness
Late term colic, severe pneumonia
Placental abnormalities
Placentitis Premature placental separation (‘red bag delivery’) Placental insufficiency (e.g. twinning)
Prolonged stage 2 labour
Dystocia
Induced delivery Caesarian section Rupture of the uterus Reduced umbilical blood flow
Umbilical cord compression or twisting
Failure to breath after delivery
Resuscitation after birth
Abnormal gestational length
Prematurity
Severe anaemia in neonatal period
Neonatal isoerythrolysis Bleeding into the chest or abdomen Severe bleeding from the umbilicus
Severe pneumonia Birth heart defects
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PREVENTION • Vaccination • EHV • Keep mares in small groups • Biosecurity • Quarantine • Determine Risk • History • Lost 2 of the past 6 pregnancies • Ascending placentitis – slip more often
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Applying Dalric Extensions Dalric extensions are a great aid in the treatment of many ALDs. They can be used medially or laterally depending on whether the deformity is valgus or varus. The main aim of the Dalric extension is to support the load forces of affected leg and to provide support for stressed sesamoids and carpal or tarsal bones as they continue to ossify. They also prevent breaking away of hoof wall which is likely due to weight bearing forces. I prefer to only use Dalric extensions on foals up to 14 days as they support the hoof completely medial/lateral and should only be taped on up to 5-7 days. After 14 days a decision can be made whether to utilise Equithane extensions or continue with Dalrics. In most cases, where a knee or hock is bowing, Dalric use should be extended. In the case of a foal rotating in, the Dalric has less mechanics (see notes) therefore other treatment is necessary. The Dalric extension has an adjustable wall which should be fitted firm but not tight, trying to allow some expansion toward the heel area. The heel area of the Dalric shoe should be modified so as to not affect the coronary band. The shoe can then be either taped on (for short periods on young foals) or glued on with either Dalric Glue (provided) or with Equithane, with the aid of Elastoplast to hold shoe in place until glue sets. When a Dalric is taped on, one wrap around the hoof capsule then continued around the Dalric helps prevent shoe twisting on the hoof.
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It is recommended in young foals (up to 30 days) that the Dalric be removed before 7 days, after that they should be removed before 10-12 days. A close daily monitor of Dalrics several days after application is essential. Watching for signs of over correction (if used medially) also in severe cases a bulging of the coronary band can occur which is an actual expansion of the coronary band not a contraction of the hoof, which many people are lead to believe. If this occurs beware of slight vertical cracks below coronary band, which left unnoticed can become infected and be very painful. If this occurs remove shoe immediately and reassess for reapplication or possible Equithane. I have noted some cases where lateral extensions are used on hind limbs with bowed hocks, where there is a lot of hock action, that the shoe can grip on ground surface which can cause an aggravation of the coronary band, resulting in a horizontal crack. Softer bedding is recommended for these applications. Most Dalrics have best results in softer bedding where available.
Applying Equithane Extensions Equithane extensions are predominately utilised laterally in cases of varus fetlock deformities and rotatedin deformities and are used often in conjunction with periostal elevation surgeries. It is not recommended for use on foals less than 14 days old or until hoof structure is capable of supporting an extension. Equithane should not be used on foals with any hoof wall weaknesses or cracks etc, as the high temperature during setting time can result in a scorching of the laminate, causing infections. Also try to avoid applying Equithane to young foals in very hot conditions as rapid setting of the Equithane causes extreme heat and may cause laminate aggravation. Try to avoid foals being subject to hard surface conditions, as there have been a number of cases of lameness associated with foals galloping on hard conditions possibly causing slight P3 fractures. The amount of extension required depends on the severity of the deviation, being aware of cases where there is a valgus knee involved with varus fetlocks, especially in some narrow chest base wide foals (see notes).
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