Something a little different from the equines he usually deals with…..
Our house surgeon, Luis Rubio-Martinez performing a vasectomy via key-hole surgery (laparoscopy) in free range African elephants during his time as faculty at the University of Pretoria (South Africa).
Laparoscopic vasectomies have been performed on the African elephants within the elephant population management program (www.elephantpmp.org). This was a collaborative project of the University of Pretoria (South Africa), Colorado State University (USA), Walt Disney Parks & Resort, Florida (USA), and San Diego Zoo Safari Park, California (USA).
We are looking for suitable recipient mares for embryo transfer for our clients.
Embryo transfer is a technique where an embryo is flushed from the donor mare and then transferred into the uterus of the recipient mare. The embryo will then develop within the uterus of the recipient mare and she will raise it as if it was her own.
Ideally recipient mares should be between 3-10 years old, have a good temperament, be healthy and over 16hh.
The mares will be well cared for at all times. Please contact the hospital on 01903 883050 for further information.
The Sussex Equine Hospital offers state-of-the-art laparoscopy surgery for horses. Laparoscopy is key-hole surgery into the horse’s belly, involving inserting a camera through small incisions to view, assess and treat internal organs such as the spleen, intestines, ovaries and retainedtesticles.
The most common procedures performed include removal of retained testicles (rigs); removal of ovaries because of tumours; closure of the nephrosplenic space (between the spleen and the left kidney) where the gut can become trapped causing colic.
Other organs can also be treated, including parts of the gut, the diaphragm, the epiploic foramen, and the bladder.
The advantages of laparoscopy are multiple. Key-hole incisions are very small leading to minimal scarring, low pain and shorter recovery times. Organs are clearer on the screen via key-hole than conventional cut-down surgery and many key-hole procedures are performed on a standing horse without the need of a general anaesthetic.
Historically, laparoscopy has been developed in humans and other animal species, including dogs, cats, ruminants and elephants.
The surgical team at the Sussex Equine Hospital, which includes Andy Crawford, Luis Rubio-Martinez, Nigel Woodford and Hannah-Sophie Chapman, have ample expertise and routinely perform laparoscopic surgery on horses.
If you have any questions or queries or any horse that you think may benefit from laparoscopy, do not hesitate to contact the Sussex Equine Hospital on 01903 883050 or email email@example.com.
Limb deformities in foals can either be ‘congenital’, meaning they are present at birth, or ‘acquired’ meaning that they develop after birth. Furthermore, within each of these categories limb deformities can be ‘flexural’ or ‘angular’.
Flexural limb deformities are commonly present at birth (congenital) and can present as the tendons and ligaments being ‘too loose’ (lax) or ‘too tight’ (contracted). The degree of contracture or laxity and, specifically, which part of the limb is involved, will affect the management protocol that will be advised by our stud vets at the new born foal exam. This may involve more or less exercise, softer or firmer bedding, splinting, casting, medical treatment or surgery.
Acquired flexural deformities develop as the foal is growing and are often associated with rapid growth spurts and/or excess nutrition. These deformities can involve individual or multiple joints and can progress rapidly, even over as little as a week. Importantly, most of these flexural problems can be corrected provided they are recognised early and treated correctly. However, if left unmanaged, they can lead to permanent unsoundness for the rest of the foal’s life. The treatment might involve restricted exercise, early weaning, corrective farriery or surgery.
Angular limb deformities are limb deviations from the normal axis of the leg. The two main types are ‘varus’, meaning an inward deviation, or ‘valgus’, meaning an outward deviation. Congenital angular limb deformities are very common and management will vary depending on how severe the deviation is and which area of the leg is involved. The major growing phase of the fetlocks is when the foal is very young (less than two months of age), so angulations involving the fetlocks must be corrected very early. This is in contrast to the knees and hocks, where we have a little more time available, as rapid growth continues until four to six months.
Acquired limb angulations such as flexural deformities commonly develop associated with imbalanced growth due to incorrect nutrition, mineral or vitamin deficiencies. Regardless of whether the angulation is congenital or acquired, management may involve restricted exercise, corrective farriery, shock-wave treatment, modified nutrition or surgery. Which option or combination of options is used depends on the degree of deviation, which joint is involved, age of the foal and other concurrent problems.
In summary, limb deformities (congenital or acquired, flexural or angular) in foals are a complex condition. Early recognition and correct treatment can usually resolve or significantly improve most of these deformities. However, a delay of a few weeks in instigating the correct management can mean a missed opportunity and a life-long conformational abnormality. It is vital that you monitor your foal’s growth closely and frequently observe your foal standing and walking on a firm flat surface so that problems are seen early. This is especially important for the farrier to be able to correctly trim the hoof.
I would advise that you immediately contact the Sussex Equine Hospital to speak to one of our stud vets regarding anything out of the ordinary with the growth and development of your foals’ limbs. We can then assess the condition and advise if there is time for conservative management or whether a more aggressive approach should be instigated immediately.
Looking after your mare during her pregnancy is extremely important to ensure the best chance of her producing and raising a healthy foal.
The mare’s diet needs to be carefully considered with the aim to increase the level of nutrition in the last three months of pregnancy. A brood mare should not be allowed to become too thin or too fat. The diet for the last trimester of pregnancy should be a proprietary brood mare diet or balancer. This will include the correct balance of minerals and nutrients for the foals development. Follow the manufacturer’s guidelines initially, then feed by eye resulting in a gradual increase in weight prior to foaling. If your mare is getting too fat on a brood mare diet then please call for more specific advice for your individual circumstances as a balancer may be more appropriate.
Your mare should be following a normal worming programme, ideally based on faecal worm egg counts as recommended by your vet. In the last month before foaling, your mare should be wormed with an ivermectin-based product, such as Eqvalan or Bimectin. This is because some worms can cross the mares’ uterus and others can cross into the milk and infect the foal when it nurses. Foals also eat the mare’s dung as a normal process during the first few months of life so good mare worming is essential.
There is a number of vaccinations that should be considered for your brood mare. Influenza and tetanus vaccinations should be up to date and ideally the mare should be given a booster vaccination within the last month of pregnancy, to boost the level of influenza and tetanus antibodies in the colostrum for the foal.
Equine Herpes Virus (EHV) mostly causes respiratory signs in horses. However Equine Herpes Virus 1 and 4 can also cause abortion. Mares at risk are those at yards where horses are coming and going and thus may bring in infection or mares that will be in contact with yearlings and young horses (as young horses are the most prone to carrying and spreading the infection). Additionally, most studs will require your mare to be vaccinated against EHV for her to be accepted on to the stud for foaling down. Vaccination to reduce the risk of abortion caused by EHV should be performed at five, seven, and nine months of pregnancy.
Rotavirus is a viral diarrhoea that can affect foals in the first few months of life. Young foals can become life-threateningly ill with this infection if not given intensive treatment and nursing. Foals most at risk of infection are those being born at properties where there has been a history of rotavirus previously or where a lot of foals will be present in the same area such as stud farms. To reduce the risk of rotavirus diarrhoea in your foal, the mare should be vaccinated during month eight, nine, and ten of pregnancy to ensure a high transfer of immunity through the colostrum to the new born foal.
It is usual to remove the mare’s shoes when foaling becomes imminent. This is to lessen the damage caused if the mare accidentally stands on the foal. However, some mares may become foot-sore without shoes. Therefore, if you have any concerns call one of our stud vets for advice. It is important to maintain hoof health with regular trims as a mare with overgrown, cracked, sore feet will not be able to remain fit and healthy for producing a foal.
If you are planning on foaling your mare down at a stud, it may be worth discussing with them what their requirements are now so you can make sure the vaccinations are performed correctly. If in any doubt, call one of our stud vet to discuss your individual situation so more specific recommendations can be made.
Sussex Equine Hospital provides the most advanced state-of-the-art treatment options available for horses with upper airway problems. These include tie backs and laryngeal re-innervation, both of which can be done standing without the need for horses to go through a general anaesthetic.
Performing the surgery standing offers many advantages to both the horse and the veterinary surgeon. It avoids the risks associated with general anaesthetic and recovery, and at the same time, offers improved visibility to the surgeon, which in the majority of cases aids completion.
Roaring occurs as a consequence of an unhealthy nerve not firing the muscle responsible for opening the airway. As a consequence, the amount of air flowing into the lungs is reduced during the horse’s physical activity, causing fatigue.
The tie-back surgery has long been recognised and practised as a treatment for ‘roaring’. During the tie-back, the opening into the airway is ‘tied’ open so that the flow of air into the lungs is increased. Laryngeal re-innervation is another surgical option available for some ‘roarers’. This technique effectively replaces the unhealthy nerve by a separate healthy nerve. During laryngeal re-innervation, the healthy nerve is identified and implanted into the main muscle responsible for opening the airway so that the horse has a good chance of recovering its ability to open its airway itself.
Laryngeal re-innervation was actually developed in the 1980s. However, in recent years, further developments and refinement of the technique now provides an excellent surgical option for many horses and the standing surgery is rapidly
becoming popular. Dr Fabrice Rossignol (Clinique de Grobois, France) is a world-renowned veterinary surgeon who has been a key figure in the recent development of laryngeal re-innervation on horses. The Sussex Equine Hospital is privileged to work closely with Dr Rossignol, who has provided his top-quality expertise and guidance for some of our more complicated cases.
Sussex Equine Hospital has already treated a good number of horses with standing tie-backs and nerve implantations on the standing horse with impressive results.
The team of dedicated stud vets at the Sussex Equine Hospital is made up of Ed Lyall, Paula Broadhurst, Simon Staempfli and Noelle Baxter. Together they provide a wide range of stud medicine services, including Artificial Insemination (AI) and Embryo Transfer (ET). The team are all very experienced and hold postgraduate qualifications in reproductive medicine. Una Boyle, the fifth member of the team, joined the practice in 2016.
Sussex Equine Hospital is the only practice in the south of England that has a team of dedicated stud vets that provide routine and emergency services to stud clients 24 hours a day, 7 days a week for the entire stud season. This means that if your mare requires routine work to be done as part of her AI programme on a Sunday it will be a stud vet who does it, not just the duty vet. It also means that at night when your mare is foaling or your foal is not well, a stud vet with experience will be on hand to attend.
The hospital is fully equipped with a lab, foal care facilities and a surgical suite for performing all necessary mare and foal procedures including caesarean sections and assisted foaling under general anaesthesia.
Following is a brief overview of AI and ET; if you have any queries or want to discuss your requirements please do not hesitate to contact the practice and speak to one of the stud vet team.
AI is the technique used to transfer appropriately processed semen, collected from a stallion, into the uterus of a mare at the correct time in her oestrus cycle in order to obtain a single pregnancy. The semen can either be fresh, chilled or frozen and it means stallions in the UK and abroad can be used, even semen from deceased stallions. Fresh semen is usually collected, extended and stored at room temperature in an airtight, light free container for use within 8 hours. Semen that is to be used longer than 8 hours after, but within 48 hours of collection should be chilled to 4ºC and stored for shipping in a special container. Semen that is required to last longer than 48 hours is frozen in liquid nitrogen at a temperature of -196ºC. The success of an AI programme is very dependent not only on the stallion’s semen but also on the careful veterinary management of the mare pre and post covering. This means that the semen is placed in the uterus at the correct stage in the mare’s cycle and that appropriate post insemination checks and treatments are made.
The other advantages of AI include keeping your mare and foal at home under your own supervision. Additionally, we find the intensive veterinary management required with mares to successfully perform AI can, in many circumstances, improve the chances of obtaining a pregnancy, as the probability of infection either bacterial or venereal is reduced. The addition of extenders and antibiotics to the semen can also improve the fertility of some stallions by improving the lifespan of the sperm. AI allows for the safe mating of mares or stallions with injuries and can prevent injury to valuable stallions by mares of poor temperament at natural mating.
At the Sussex Equine Hospital we use the most up-to-date techniques to manage AI mares, including insemination of frozen semen using a deep intrauterine technique. Over the last few years this technique has been used to inseminate mares with small volumes of chilled as well as frozen semen from the continent and we have seen a significant rise in the in-foal rate. Experience of dealing with thousands of mares over the years has allowed us to develop effective, simple routines and protocols for artificial insemination. Attention to detail is the key to good mare fertility and achieving a pregnancy as quickly as possible. The collection of frozen semen can allow a stallion to compete internationally without having to worry about stud duties and temperament changes whilst covering.
Similarly Embryo Transfer (ET) is a technique that has been developed to enable mares to continue to compete while still producing foals. A mare’s fertility decreases as she gets older and this reduction in fertility appears to be more rapid in mares that have never had a foal. Therefore, once a mare is retired from competition in her teenage years and put to stud, her ability to become pregnant can actually be very poor.
To try and avoid this situation, owners will sometimes breed from fillies at 2 to 3 years of age prior to breaking in, so that they at least have 1 offspring before starting a competition career. Alternatively, ET can be used to produce foals while the mare is actively competing. Embryo Transfer involves the careful synchronisation of a donor mare (the mare you want the foal from) with a recipient mare (the mare we will transfer the pregnancy into). Then on a day individually selected depending on the situation, (usually day 7 or 8 after ovulation), the embryo is carefully flushed out of the donor mare and transferred to the recipient mare. A pregnancy scan is then performed about 1 week later on the recipient mare and subsequent scans as indicated.
The synchronisation of the recipient mare with the donor mare plays a large part in the success rate of this procedure and it can be quite difficult to do as not all mares ‘read the text book’ and respond to the medications the way we would like. Therefore, we ideally need to start off with a number of potential recipient mares so if some don’t respond as hoped we still have others to choose from. Fortunately, studies have shown no decrease in the success rate of the transfers, if the embryos are carefully chilled and transported within 24 hours to a facility with a number of recipient mares available.
Since 2008 the stud vet team at the Sussex Equine Hospital have performed a large number of successful ETs by flushing the donor mare and directly transferring the embryo into a recipient mare or sending the embryo chilled to a recipient mare facility. The donor mares are covered via AI in their own stable yard or at one of our AI centres. The flush can be carried out at the yard, AI centre or at our hospital. The flushing process takes between 30 and 60 minutes to perform, then the donor mare can go home to continue her normal competition routine. Once processed properly the embryo is either directly transferred into the recipient or transported chilled, same day by courier to the recipient mare facility where the embryo is transferred into the mare that was best synchronised with the donor.
Image shows a 7 day embryo
Over the last few years we have paid attention to detail and developed protocols that have given us excellent success rates with transferred embryos.
We aim to allow sport horse mares, that are of importance for breeding, to remain in work and competition. Our protocols mean that mares can remain at home with the rider so there is no check in training or competition.
New for 2018 we will be offering a service in the hospital where we will be able to freeze embryos, these can be stored for future transfer or even sold to other parties.
Packages for Veterinary Stud Work
Prior to embarking on an AI or ET programme with a mare it is important to become aware of all the facts and to balance out the pros and cons. One of the most important factors to consider is the cost. The keep, transport and veterinary costs sending the mare away to stud, must be balanced against the veterinary costs of AI or ET and keeping the mare at home. Many of the veterinary costs will be incurred either way and so it can be a real advantage to keep the mare at home. Some veterinary practices, as we do, will have a fixed price scheme for AI programmes. These can vary considerably, they may require the mare to go to a stud that the vet attends regularly and some may not include visit fees, pre-breeding swabs or pregnancy scans - when making price comparisons look very carefully at what is included in the package!
If you are interested in breeding from your mare in 2018 via natural cover, AI or ET contact the SEH now so that one of our dedicated Stud Vet team can explain the process in greater depth to you, one on one. Your options and which one of our competitive package deals best suits your individual situation can then be discussed. Mares can be worked on at owners’ yards within the practice area or mares from further afield can be boarded at the hospital or at one of several AI centres that we service.
Not only does the stud team take great care to get mares in foal as quickly as possible, they are also dedicated to the health of the newborn foal. We perform post foaling checks on both mares and foals within the first 12 hours after foaling, blood samples can be taken to assess health and also to make sure enough antibodies have passed from the mare to the foal by monitoring the IGG level of the foal's blood. All samples are processed in our own lab at the hospital.
The team will advise on future foal management, particularly of the limbs of the foal and also any other medical issues, as well as routine protocols such as worming and vaccination.
The hospital is equipped with two purpose built intensive care foal boxes, this allows us to deal with very sick foals and provide them with the very best levels of medicine possible. The hospital also has the surgical facilities required to perform all necessary mare and foal surgeries.
Stallion Semen Collection
Also new for the 2018 season we will be offering semen collection from stallions for fresh and chilled use. We will be able to send out semen 5 days a week across the UK. This service will be available to all stallion owners, however, prior to collection all stallions will need to have been tested to meet the strict health guidelines - for more information please do not hesitate to contact one of the stud team.
There are numerous types of gastrointestinal parasites or “worms” as they are more frequently referred as. Worms are a burden on the horse’s gastrointestinal tract (GIT). This burden can range from being completely sub-clinical (the horse shows no ill effects from the infestation) to reducing a horse’s performance in events, causing colic, diarrhoea, weight loss and in severe cases horses can die as a result of parasitic infestation.
The most common and pathogenic worms that infest horses are, cyathostomins (small worms or small redworms), large strongyles (large red worms) and tapeworms. Large red worms were historically a problem but are now far less prevalent and cause less clinical disease. Small red worms are very common affecting all ages but mainly young horses (1-4 years old). Most infections are subclinical.
The small red worm life cycle: the larvae are eaten by the horse off the pasture and move through the GIT. They then burrow into the gut wall and can stay there for weeks, months or even years. They stay there until conditions are just right then they emerge from the gut wall and mature into adults where the adults produce eggs that are shed in the faeces. The eggs in the faeces then develop on the pasture into the larvae that are eaten and so the cycle continues.
The larvae in the gut wall are called “encysted” and these are very difficult to treat. Only two drugs can target these encysted larvae: a 5 day course of Fenbendazole or Moxidectin. If a large number of worms erupt from the gut wall at the same time then horses can develop severe problems. Encysted larvae don't produce eggs and so it is important to remember that a horse can have a low faecal egg count (FEC) but still have a high worm burden.
The tapeworm life cycle is different as they don't burrow into the wall but they shed their eggs intermittently so a negative WEC does not mean no tapeworms. A high tapeworm burden can cause colic. A blood test is available to detect antibodies against tapeworms, but this only gives an indication that they have been exposed at some point in the last 6 months.
|Adults||Encysted Larvae||Annual/6 month dose|
|1 d Fenbendazole||√||χ||χ|
|5 d Fendendazole||√||√||χ|
Anthelmintic “wormers” have different effects and so target different worms at different stages of their life cycle. This table shows which worms are killed by the different active ingredients in wormers.
80% of worms produced in a field come from 20% of the horses. This means that the majority of horses on a pasture have few worms and so produce only a very small number of eggs. These horses are ‘low egg shedders’ and they do not need worming as they won’t be suffering adverse effects of having worms and won’t be significantly contributing to pasture contamination. The small group of horses that make up the 20% will be ‘high egg shedders’. These horses will have a FEC>200 eggs per gram. For an unknown reason these horses will be persistent egg shedders despite the same or similar pasture management as their herd mates. It is these horses we need to target with wormers to reduce pasture contamination and infectivity.
Each time you worm your horse a small number of the worms present will be resistant or “immune” to the effects of the wormers you use and so will survive worming. If you repeatedly give the same type of wormer to all horses on the pasture, over time the number of resistant worms in your horses' GIT will increase until all the worms are resistant and your wormer will no longer work. The oldest wormers (Fenbendazoles) have the highest resistance and the newest wormers have the least resistance (Moxidectin). It is important to understand that there are no new wormers being generated. Donkeys are already resistant to Moxidectin.
If you are worried about resistance developing on your yard then your vet can perform a faecal egg count reduction test (FECRT). This test measures the efficacy of the wormer you have used.
To reduce the development of resistance we can do four things:
1. Allow a population of sensitive worms “refugia” to survive the worming process. These refugee worms will dilute and compete with the resistant worms for resources. This competition will stop the development of an entirely resistant population. To do this we have to use a targeted worming protocol.
2. Reduce the use of wormers by only worming those horses with a FEC above 200 epg.
3. Manage the environment to minimise our reliance of wormers. We can do this by reducing the number of horses per acre, regular poo picking (everyone’s favourite summer pastime), mixed grazing with sheep and cattle and finally harrowing fields on hot dry days so the sun destroys the eggs in the soil.
4. Quarantine new horses so they don't bring resistant worms onto the yard. New horses should also be wormed for tapeworm and encysted larvae before being turned out.
Firstly, no one protocol will work for every yard and if you have any concerns please consult your vet about your specific yard requirements so we can tailor a programme for you.
Regular worming - worming every 4-6 weeks will reduce disease BUT will lead to resistance and a shift in the type of worms you will see, so this is NOT a sustainable management protocol. Worming at specific times of the year can be successful in disrupting the worms' life cycle, however, changes in weather pattern or the introduction of heavily contaminated individuals will reduce your success and won’t help heavily burdened horses.
Targeted worming - treating each horse as an individual is the BEST strategy. You must use a FEC to select those horses who are shedding >200 epg and only worm those horses, the “high egg shedders”. By doing this you will reduce pasture contamination and reduce the development of resistance. It is also a CHEAPER worming protocol. You must have a FEC from every horse because 80% of the worms are produced by 20% of the horses so in a herd of 30 horses only 6 will be significantly shedding eggs but you won’t know which six unless you sample all 30.
We recommend that as part of any worming strategy, tapeworm should be targeted twice a year in autumn and spring, and that encysted worms are targeted in winter.