Does soaking make hay safer for laminitics?

An important part of treatment and prevention of laminitis is to limit the water soluble carbohydrate (WSC) intake. To achieve this, access to pasture is restricted and the horse or pony is fed hay instead.

But even hay may not be safe for horses with laminitis. Most authorities suggest that horses and ponies prone to laminitis or with insulin resistance should ideally receive hay that has a water soluble carbohydrate concentration not exceeding 100g/kg on a dry matter basis (DM)

However, in northern Europe pasture grasses often contain high levels of WSC (>300g WSC/kg DM), which may result in hay with WSC content up to 200g/kgDM.

It is often suggested that soaking the hay may reduce its water soluble carbohydrate content and thus make it safer for laminitis-prone horses and ponies. However, the studies that have supported this approach have often used large quantities of water and, as well, the hay may have been chopped prior to soaking.

Often owners do not go to such lengths. What is the effect of soaking hay when carried out according to common practice?

Dr Annette Longland, Clare Barfoot and Dr Pat Harris conducted an investigation into whether the degree of soaking that is in common use in the UK would have an effect on the WSC content of various hays.

The study looked at the loss of WSC and crude protein from a range of British hays, which were either shaken or left compacted in the "flake" and then soaked in just enough water to cover the hay, for various lengths of time.

The authors found that soaking hay for up to 16 hours produced variable and incomplete loss of WSC.
As would be expected, the dry matter content of the hays fell after soaking - there was a significant reduction in DM content after 20 minutes soaking, and a continued fall with longer periods of soaking.

However, regardless of the duration of soaking or whether the hay was shaken up or left compacted the WSC content of most of the hays remained above the recommended limit for laminitics of 100g/kgDM.

The researchers found no significant difference between the compacted or shaken hays. They conclude that soaking cannot be relied on to make hay suitable for feeding to laminitic horses.

They recommend that hay for animals prone to laminitis be analysed for WSC content, and only hay that is low in WSC is fed to horses prone to laminitis. Soaking can be used as an extra safeguard.

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Magdalena Zabek's latest report on the feral horses of central Australia is now available. Click here to read

Research confirms effectiveness of grazing muzzles

Using a grazing muzzle appears to be more effective than restricting access to pasture, for reducing the amount of grass eaten by ponies, according to a recent study.

Pasture intake by the ponies grazing for three hours without muzzles averaged 0.8% (with some eating close to 1%) of their bodyweight, which is the equivalent of up to two thirds of the recommended daily dry matter intake  for many ponies on restricted diets.

In contrast, the pasture intake of the ponies when wearing muzzles was around 0.14% of bodyweight over three hours, representing an average reduction of 83% compared to when they were not wearing muzzles.

Read more at www.equinescienceupdate.com

Making sense of flexion tests

Flexion tests are often used as part of a prepurchase examination or a lameness work-up to evaluate lameness or assess the likelihood of future lameness problems. But what does a positive flexion test tell us about which structures are involved?

Research published in the Equine Veterinary Journal suggests that the fetlock is probably responsible for a positive response to flexion test of the lower limb. Structures below that joint are less likely to be involved.

Dr Clodagh Kearney and colleagues conducted a study on eight warmblood horses. These were all clinically sound, but had gone lame after being subjected to a flexion test of the lower limb. Flexion tests were performed under standardised conditions.

The response to the flexion test was assessed after performing various nerve blocks, which desensitised different regions of the limb. One clinician performed the nerve blocks; others performed the flexion tests and assessed the degree of lameness. So the clinicians assessing the lameness did not know which nerve block had been carried out (or on which leg).

They found that a nerve block of the palmar digital nerves, just above the cartilage of the distal phalanx, had minimal effect on the lameness induced by the flexion test. A nerve block just below the fetlock at the level of the distal abaxial sesamoid bones produced a similar response. However, there was a marked improvement in flexion test induced lameness following a low four point block just above the fetlock.

The researchers conclude that the fetlock joint and surrounding structures contribute strongly to the outcome of a flexion test of the lower limb in a non lame horse. "From a clinical point of view, it is reasonable to suggest that the flexion test of the distal limb may be sensitive for investigating the metacarpophalangeal joint region, but may be less relevant for structures distal to this joint."

Read more at www.equinescienceupdate.com

Treponemes found in canker lesions

Japanese research has found evidence of treponemes in equine canker by looking for specific portions of RNA characteristic for the organisms.

Canker is a chronic proliferative condition of the horse's foot - affecting the frog and bars and sole. In severe cases it may extend to involve the hoof wall. Similar conditions in cattle and sheep have been shown to be associated with spirochete bacteria - in particular treponemes.

Dr Kyaw Kyaw Moe and colleagues examined samples from lesions in two horses and compared them with samples from an unaffected horse.

They found spirochetes in microscopic sections of the canker lesions. They also found 114 clones in the affected horse samples and none in samples from normal horses.

The clones could be classified into 19 separate groups - corresponding to many different treponemes, including those implicated in bovine papillomatous digital dermatitis.

Despite this the researchers were unable to culture the organisms. This is not surprising as treponemes are slow growing and are often overgrown by more rapidly growing bacteria.

The research confirmed the presence of treponemes in canker lesions in two horses and their absence in a normal horse. However, as the study was based on only a couple of cases, the researchers could not confirm that treponemes are the cause of canker - further work is required involving more cases.

Read more at equinescienceupdate.com

Effect of psyllium on glucose and insulin

Psyllium, a sort of "super-bran", is already used in horses, particularly for treatment and prevention of sand colic. When mixed with water, it swells to up to 10 times its original volume, turning into a jelly-like substance which is thought to ease the passage of sand through the digestive tract.

Researchers at Montana State University conducted a trial to see if adding psyllium to a horse's diet had an effect on glucose and insulin metabolism. It had been noticed previously that psyllium had a beneficial effect on insulin sensitivity, when taken by people with insulin resistance. So they wanted to investigate whether a similar effect occurred in horses.

They used 16 healthy horses (8 mares and 8 geldings), which they divided into 4 groups of 4, each containing 2 mares and 2 geldings. All horses were fed a diet of mixed grass hay and a commercial whole grain feed twice a day. Psyllium pellets were added to the grain ration of three groups at 90g, 180g, or 270g daily. The fourth group received the same diet, but without added psyllium.

On the 60th day the researchers withheld food from the horses overnight. In the morning they collected blood samples before the morning feed and then every 30 minutes for six hours, to monitor the blood glucose and insulin concentrations.

The researchers found that on average, horses that had been receiving psyllium for 60 days had lower average peak glucose levels after feeding and lower average glucose levels. Psyllium-fed horses also had lower peak insulin levels and lower average insulin levels after feeding compared with horses that had not received psyllium.

Dr Shannon John J Moreaux, Assistant professor of Equine Science at Montana State University, and one of the research team commented. "Psyllium could be especially beneficial to obese, insulin-resistant horses, or horses that are predisposed to developing laminitis because of metabolic syndrome". He added that it was commercially marketed and readily available to horse owners, and when fed daily, may help to maintain lower post-feeding blood glucose and insulin levels.

This was a small study carried out using normal horses. Before we can conclude that psyllium will benefit insulin resistant horses, further research is needed using affected horses.

However, if it proves to be effective in insulin resistant horses it could provide a useful addition to the strategies available for managing this condition.

Read more at equinescienceupdate.com

Is your vet a health risk?

Vets that work with horses are more likely than other vets to carry methicillin-resistant Staphylococcus aureus (MRSA), according to an Australian study.

The researchers, led by Dr David Jordan, collected nasal swabs from 771 individuals, who were also asked for details of the type of work they did and with which species.

Analysis of the data showed that veterinarians that worked mainly or exclusively with horses were more likely the carry MRSA in their nostrils.

MRSA was present in 5.8% of those taking part in the study. However, the data revealed differences depending on the type of work the individuals performed.

Positive swabs were obtained from 11.9% of veterinarians who spent a lot of their time on horse work. (This was 13 times that of the vets involved in industry or government work. Less than 1% of them had positive swabs).

The figures were even higher among people who worked only with horses.  The results showed that 21.35% of them had nasal swabs positive for MRSA. (They were 23 times more likely to have their nostrils colonised by MRSA than were vets working for government or industry.)

Considering the extent of carriage of MRSA and the seriousness of the disease it can cause in humans and animals, Dr Jordan recommended that vets should take more precautions to prevent the spread of MRSA

"The higher than normal prevalence of MRSA carriage among veterinary clinicians in Australia is a cause for concern in the profession and warrants further investigation for specific risk factors, particularly for vets who work with horses"

He suggests that guidelines specific for equine work are needed. These should include: "enhanced personal hygiene during handling of animals; better sanitary management of premises, equipment and waste; greater awareness of biosecurity during handling and surgical procedures; and reform of use of antibiotics - especially those of importance in human medicine such as the fluoroquinolones, third generation cephalosporins and gentamicin."

Read more at www.equinescienceupdate.com

Hendra virus vaccine progress

Australian scientists have succeeded in developing an experimental vaccine to protect horses against Hendra virus.

Hendra virus (HeV) was first isolated in September 1994 from an outbreak at a training complex in Hendra (a suburb of Brisbane, Queensland, Australia) after which the virus was named.

During that initial outbreak 14 horses died. Seven other horses were found to have been infected and were humanely destroyed. Two humans were affected, one of whom died.

In five of the 14 known outbreaks, the infection has spread to people. The virus has killed four of the seven people infected.

Fruit bats (Pteropus spp), commonly known as flying foxes, have been identified as the natural host for the Hendra virus.

“Our trials so far have shown that the vaccine prevents the infection of horses with Hendra virus,” said Dr Deborah Middleton from the Australian Animal Health Laboratory (AAHL).

Stopping the disease in horses could also help protect people from the disease.

"All the human infections have come from contact with infected horses," Dr Middleton explains. So if you can control the disease in horses, you break the transmission cycle to people as well as protecting the health of horses.

Studies so far have shown that the vaccine will prevent horses becoming infected. It also protects them from developing the disease and shedding the virus.

Further work, including field trials and product registration, is still required. However, if all goes well, the vaccine may be available as soon as 2012.

Dr Barry Smyth, President of the Australian Veterinary Association, said that both vets and horse owners would welcome the news on the vaccine.

“It’s important that veterinarians and horse owners continue with precautions that reduce the risk of spreading the virus and that they report suspected cases immediately,” Dr Smyth said.

Read more at: www.equinescienceupdate.com

Saddle research uncovers new theory in asymmetry

The Saddle Research Trust (SRT), believe they have discovered a new theory in rider asymmetry, which they feel will have implications for equine performance and welfare.

Following a series of pilot studies carried out in conjunction with educational establishments throughout 2010, the charity claims to have evidence that highlights previously unidentified areas and measurable characteristics of saddle performance.

Anne Bondi BHSI, Director for the trust explains: “The initial objective of our early pilot studies was to measure the effect of the rider asymmetry using a variety of scientific measuring systems open to the trust. It soon became apparent that a more complex pattern of interaction was occurring, one that could not just be explained by a rider sitting crookedly.”

Humans are not perfectly symmetrical, and most riders are aware of being right or left handed. This ‘handing’ often creates a loss of symmetry in the rider in the vertical plane.

“After observing this common occurrence we began to examine further the effect the saddle has on the rider and their posture” she continues.

A similar lack of symmetry also exists in the horse in the horizontal plane. The movement of a horse’s back and limbs creates movement in the saddle, generating an unstable platform for the rider. This forces riders to adopt a compensatory action - accentuating the already asymmetrical posture. The horse also compensates for carrying the asymmetrical rider by counterbalancing.

According to the SRT, this is far more complex than a ‘chicken and egg’ situation. It involves a mixture of symptoms involving asymmetries in the horse, rider and saddle, but more significantly the interaction between them.

"Our studies to date have shown a clear lack of synchronisation in this three-way interaction, and it is our understanding that the degree to which this occurs is greatly affected by saddle design and fit."

“We have raised many new questions about the effect of saddles on asynchrony, as well as identifying measurable characteristics in saddle performance. Although our work is in its infancy we believe it will have far-reaching effects on all levels of equestrianism.”

Read more at www.equinescienceupdate.com

Bedding dope test risk

Flunixin excreted in the urine may be ingested with bedding, risking prolonging the time taken to clear the drug from the body.

Owners and trainers should be aware that horses may recycle anti-inflammatory drugs such as flunixin in the stable environment. This may prolong the time the drug is detected in the urine - thus increasing the risk of positive dope test.

Flunixin is a non-steroidal anti-inflammatory drug commonly used in horses. The rules of many disciplines prohibit its presence in the blood or urine of horses on the day of competition.

Detection times have been established for some medications to help veterinarians advise owners and trainers on how long before a competition treatment should be withdrawn to minimise the risk of the drug being found in the urine. However, research in France shows that the problem can be complicated by horses absorbing flunixin from bedding that has been contaminated by urine containing the excreted drug.

Work at the Laboratoire des Course Hippiques, found that, even if bedding is removed completely and the floor brushed out, there is still a risk of a "rebound" increase in urine flunixin levels.

Dr Marie Agnès Popot and colleagues looked at the excretion profiles of flunixin in urine collected from horses under various systems of stable management. They gave flunixin as either a single intravenous dose (1mg/kg) or as an oral paste (0.5mg/kg twice daily for 3 days).

Horses were housed in stables from which the bedding was either completely removed on a daily basis, or only "skipped out" (removing only soiled bedding on a daily basis, and cleaned completely once a week.)

The largest rebound in urine flunixin concentration was seen in those horses kept in stables that were not cleaned completely on a daily basis. However, removing all the bedding and sweeping the floor could not totally prevent rebound in flunixin levels. The only circumstance in which a rebound in urine flunixin levels did not occur was when the drug was given intravenously and the horse was moved to a clean stable after 24 hours.

"Flunixin is mainly eliminated by renal clearance and a large amount of flunixin is eliminated in urine within the first 24 hours following administration" the researchers explain in a report in the Journal of Veterinary Pharmacology and Therapeutics. "Then, for horses housed in unclean boxes, the conditions  exist for the possibility of prolonged recycling; the only way to break recycling is to move the horse in  another separate box after the first 24 hour of treatment, rendering unavailable the flunixin excreted in the urine for the first 24 hour."

They conclude that attention to stable hygiene can drastically reduce the risk of spurious drug excretion profiles for drugs such as flunixin that are mainly eliminated in the urine.

Read more at www.equinescienceupdate.com

Focusing on the next obstacle

Elite riders' eye movements may be key to show jumping success. Research from Nottingham Trent University found that an experienced show jump rider focused on the jump up to 3.05 seconds earlier before take off than did a less experienced non-competitive rider.

http://www.ntu.ac.uk/news_events/news/releases/eyegaze.html

Mares behaving badly

Plant oils might provide the answer to mares that are unruly when in season.

Some mares become unruly and difficult to manage when in season and perform poorly as a result. Various methods of controlling this behaviour have been suggested. Most are based on suppressing the oestrus cycle.

Sandra Wilsher and Professor Twink Allen at the Paul Mellon Laboratory of Equine Reproduction, Newmarket, England, were investigating the mechanisms of maternal recognition of pregnancy.

They found that intrauterine administration of oestrogen in fractionated coconut oil prevented mares returning to oestrus, However, they also found that the coconut oil alone (without oestrogen) had a similar effect, as did peanut oil.

Fractionated coconut oil was most effective when given 10 days after ovulation - luteolysis was delayed in 11/12 mares (92%). It was not as effective on days 8-12., although the difference was not statistically significant. When administered on the 6th day after ovulation, it inhibited luteolysis in only 25% of mares. 

Oestrogen in mineral oil, or mineral oil on its own did not block luteolysis when given 10 days after ovulation.

So it seems unlikely that embryonic oestrogens are important in the maternal recognition of pregnancy.

Fractionated coconut oil and peanut oil each contain various different fatty acids.  The researchers were unable to identify an individual component that was responsible for inhibiting luteolysis.  Instead, they suggested that it is likely that a range of fatty acids are capable of causing luteal persistence.

Further work is required to determine how the vegetable oils have this effect. However, it does seem that they may provide a practical way of preventing unruly behaviour in oestrus mares.

Read more at www.equinescienceupdate.com/articles/popmb.html

Sublingual detomidine for needle-shy horses

How do you sedate a needle shy horse? Recent research suggests that detomidine, a sedative commonly used in horses, can be effective when administered under the tongue.
 
Detomidine is a popular choice for sedating horses, capable of producing profound sedation when administered intravenously.

Previous studies have shown that detomidine is not effective when administered by stomach tube, and is variably effective when mixed with food. However it seems to be absorbed through the gums and appears to be effective when given sublingually.

Recent research looked at the value of sublingual detomidine for sedating horses known to need sedation to permit routine management or veterinary tasks - such as farriery, routine dentistry, passage of a stomach tube or clipping.

The study by Dr Rachel B Gardner and colleagues was published in the Journal of the American Veterinary Medical Association.

Horses used in the study were all known to require sedation or strong additional restraint - such as a twitch - to allow the procedures to be carried out.

The treatment group comprised 129 horses treated with detomidine sublingually, at a dose of 0.04mg/kg (double the usual dose when given intravenously).

A further 42 horses were treated with a gel which appeared identical, but did not contain detomidine. The study personnel did not know whether they were administering the detomidine gel or the placebo.

The efficacy of the treatment was assessed according to whether it allowed the required procedure to be carried out. Treatment was only considered successful if the procedure could be completed without resort to further sedation or the use of a twitch.

The procedures were completed successfully in 98 of 129 (76%) of detomidine treated horses compared with only 3 of the 42 (7%) of control horses. Little or no ataxia was reported in 70% of detomidine treated horses

Sublingual detomidine was most successful for sedating horses for manual teeth floating and hoof trimming and shoeing. It gave a lower success rate for clipping with electric clippers - only half of the detomidine-treated horses could be clipped successfully.

For more details see:

Efficacy of sublingual administration of detomidine gel for sedation of horses undergoing veterinary and husbandry procedures under field conditions.
RB Gardner, GW White, DS Ramsey, JE Boucher, WR Kilgore, MK Huhtinen
J Am Vet Med Assoc (2010) 237, 1459 - 1464

No benefit in metformin IR study

A study into the pharmacological management of insulin resistance using metformin, failed to demonstrate any benefit.

The research was conducted by the School of Animal and Veterinary Sciences, Charles Sturt University in New South Wales, Australia and the Department of Clinical Studies, New Bolton Centre, University of Pennsylvania, PA, USA, in collaboration with the Waltham Equine Studies Group. Lead researcher was PhD candidate Kellie Tinworth.

In insulin resistance, insulin seems unable to exert its normal effect. This is particularly noticeable in relation to glucose metabolism. As a result, the body releases increasing amounts of insulin, ending up with normal or raised blood glucose levels despite high concentrations of insulin.

Insulin resistance appears to be a significant risk factor for conditions such as laminitis.

Therefore, it is important to prevent IR from developing, or to manage it before it contributes in turn to the development or progression of other potentially life-threatening conditions.

While the correct management of energy intake and exercise levels is thought to be essential, in some cases medication is also considered, especially when increased exercise is not possible.

No licensed drugs are currently available for treating insulin resistance in horses and ponies. Metformin has been suggested as a possible treatment for the condition. It appears to enhance insulin sensitivity of peripheral tissues without stimulating insulin secretion.

The research team hoped to confirm that metformin had a positive effect on insulin and glucose dynamics in insulin-resistant ponies, so that it could be used as a positive control in other studies.

Six ponies that were insulin-resistant, but not obese, took part in the study. Three ponies were allocated to the treatment group, and they received metformin (at 15mg/kg bodyweight orally, twice daily) for 21days. The control group received a placebo.

After a "wash out" period, the trial was repeated with the ponies being swapped between the treatment and placebo groups.

The response to metformin (and the placebo) was assessed using a frequently-sampled intravenous glucose tolerance test (FSIGT).
 
The researchers found no measurable benefits of metformin. No significant change was noted in any of the indices of insulin sensitivity. Neither was there any change in bodyweight, body condition score or cresty neck score.

Read more at: www.equinescienceupdate.com/articles/nbmir.html

Role of bacteria in periodontal disease

Bacteria may be more important in the development of periodontal disease in horses than previously thought, according to research carried out at the University of Edinburgh.

Equine periodontal disease is a common condition in horses affecting around 60 percent of horses over the age of 15 years. The disease is painful and can have a big impact on a horse's quality of life, affecting the animal's ability to eat and its performance.

Bacteria are known to be a cause of periodontal disease in humans, cats and dogs, but it is less clear what role they play in the disease in horses. Mechanical factors, such as food being packed between the horse's teeth due to abnormal growth and spaces have been considered to be the primary cause.

Research, carried out by Alistair Cox, is believed to be the first to describe the microscopic anatomy of equine periodontal disease.

Cox examined the skulls of 22 horses that had been submitted for post mortem examination. Although none of the horses had received treatment for periodontal disease, 16 had some form of periodontal disease.

"This research, funded by The Horse Trust, highlights how common periodontal disease is in horses. Yet many horses don't receive treatment so are likely to be suffering in silence. I would advise all horse owners to get their vet or equine dentist to regularly check their horse to see if it is developing the condition," he said.

Cox identified bacteria, including spirochaetes, that were associated with periodontal disease. Spirochaetes are known to be important in human and canine periodontal disease, but this is the first study to identify them in association with the condition in horses.

"This study shows that bacteria may be more important than was previously thought in the development of equine periodontal disease,” said Cox

"More research is needed to understand whether bacteria or mechanical factors are the main cause of the disease. Once we have a better understanding of why and how the disease develops, we can do more to prevent horses from developing this painful condition."

Read more at: http://www.equinescienceupdate.com/articles/rbpd.html

FIS test success

One year on, the test for Fell Pony Syndrome, has been acclaimed a great success.

As the genetic test identifies carrier animals, it can be used to prevent affected foals being conceived.  The disease only appears when both parents carry the mutation. Breeders can avoid producing affected foals by ensuring that they do not breed two carriers together.

Of the almost 1000 animals tested, 47% of Fell ponies and 10% of Dales ponies were found to carry the mutation for the disease.

The fatal disease is now known as Foal Immunodeficiency syndrome (FIS), as cases are not confined to one breed. Affected foals die or are euthanased, usually before they reach three months of age.  

Since February 2010, when the test became available, nearly 1000 samples have been tested. Three quarters of the samples came from Fell ponies. Of those tested, 47% of Fell ponies and 10% of Dales ponies were found to carry the mutation for FIS.

The test was developed as the result of research led by Dr June Swinburne of the Animal Health Trust, Newmarket. 

"This test, developed using funding from The Horse Trust, has been a massive success among the Fell and Dales pony breeding communities," she said. "We hope the test will prevent unnecessary suffering among Fell and Dales pony foals as breeders can now easily prevent the conception of foals with FIS. As so many breeders tested their breeding stock last year, we hope there will be very few foals affected by this horrendous disease in the future."

Read more at: http://www.equinescienceupdate.com/articles/fists.html

Does restricting grazing really reduce grass intake?

A recent study suggests that limiting access to pasture may not be effective at reducing grass intake by ponies

 

Recent research, about to be presented at a biannual nutrition meeting in the US, suggests that ponies given reduced access to pasture can eat considerable amounts of herbage during the time they are turned out. Indeed they may even increase their intake during this time as they become accustomed to the routine.

Intake of large amounts of fructan, and other rapidly fermentable carbohydrates by grazing ponies has been linked to the development of laminitis.  It has become common practice to restrict ponies’ access to pasture, especially at key times of the day/year in order to reduce the risk.

The study, which was conducted at the Institute of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, in collaboration with the WALTHAM Equine Studies Group, aimed to investigate the effect of grazing restriction on herbage intake and grazing behaviour in ponies.

The grazing behaviour of eight ponies was measured daily over a six week period to assess their voluntary intake of herbage and to monitor the effects of restricting their access to pasture. Two groups of four pony mares were used. Group A had 24 hour access to pasture. The ponies in group B had three hours of pasture access daily and were stabled for the remaining 21 hours, with free access to haylage and water.

Herbage intake was estimated during the three hours when all the ponies were at pasture by monitoring the change in weight of each individual over the period. Grazing behaviour was analysed from video footage of the two groups using interval sampling. The ponies in the restricted grazing group had higher estimated grazed herbage intakes than those with 24 hour access to pasture .during the three hours studied. The difference was significant during the final week, when the restricted grazing group consumed 40% of their total daily dry matter intake as grass in the three hours at pasture. This compared with an intake of grass of around 25% of their daily dry matter ingested during the first week.

 

Clare Barfoot, research and development manager at SPILLERS®, said: “This suggests that ponies with reduced access to pasture are capable of ingesting considerable amounts of grass during the time they are turned out and may indeed progressively increase their intake during this time, indicating that the behaviour could be learned. The implication is that reducing ponies’ time out on normally managed pastures with the view to limiting the intake of rapidly fermentable carbohydrates may not be as effective as first thought.”

Reference:

Changes in proportions of dry matter intakes by ponies with access to pasture and haylage for 3 and 20 hours per day respectively for six weeks. 

 J. Ince,A. Longland,C. J. Newbold,P. Harris.  

Journal of Equine Veterinary Science (2011) (in press)

Vancomycin-resistant bacteria in equine manure

Horses are not likely to play a major role in the spread of one type of antibiotic resistant micro-organism, to humans, according to a study in North West England.

Work reported at the International Conference on Antimicrobial Research in Valladolid in Spain November 2010 looked for vancomycin resistant enterococci (VRE) in equine faeces.

Lead researcher Dr Mohamed O Ahmed presented the results of the study, which looked at faecal samples from 66 hospitalised and 72 non-hospitalised horses.

Enterococci are enteric bacteria found in the digestive tract of many humans and animals. They may be responsible for urinary tract or wound infections (i.e. nosocomial infections). Also in patients with suppressed immune systems, they can cause serious conditions such as infection of the heart valves (endocarditis) and brain (meningitis).

Enterococci are naturally resistant to many antibiotics. One of the few last-choice antibiotics used for treating people with serious enterococcal infections is vancomycin.

Vancomycin-resistant enterococci is an emerging nosocomial organism, reportedly of zoonotic nature. There are several strains of vancomycin-resistant enterococci. The genes conferring resistance have probably been acquired from other types of bacteria that don't cause disease, but are already vancomycin resistant.

If specific vancomycin-resistant strains were present in horse faeces (i.e. VanA and VanB phenotypes) they could act as a zoonotic source of infection.

Overall, the researchers identified 47 suspected VRE isolates from a total of 264 faecal samples. Of those, only 9 were confirmed by polymerase chain reaction (PCR). Seven were confirmed as VanC genotype. Six of these were found in samples from hospitalised horses.

They identified one isolate each of VanA and VanD genotype. Both of these were in non-hospitalised horses, but neither could be typed by PCR.

The VanA genotype has been reported predominantly as the one involved in human infections. However, the VanC genotype, which was found most frequently in this study, is not commonly isolated in cases of human infection.

The researchers conclude that it is unlikely that horses play a major role in the transmission of VRE to humans in that specific geographic area. Also, the fact that most of the VRE isolates were found in hospitalised horses, suggests that hospitalisation could increase the risk of transmission between horses and possibly to humans too. Future research may be needed to look into this.

Read more at www.equinescienceupdate.com

Study finds whipping racehorses pointless

Whipping has no effect on the likelihood of a horse winning or being placed, according to a recent report. The authors conclude that whipping tired horses in the name of sport is very difficult to justify.

Dr David Evans and Professor Paul McGreevy based their findings on the horses’ speed, the number of times they were whipped and their place in the field. The information was gathered from five sprint races (over 1200-1250 meters) at the racetrack at Canterbury, New South Wales. 

“When we compared the sectional times 600-400m, 400-200m, 200m – finish, horses ran fastest in the 600-400m section, during which no horses were whipped”  Dr Evans explained. “Horses achieved their highest speeds during the last 600m of the races without being whipped.”

 “Increased whip use was most frequent in the final two 200 metre sections when horses were fatigued.''

“Analysis of the data showed that the strongest predictor of racing success was where a horse was placed at the 400m and 200m marks. Neither whip counts in the final 400m or 200m, nor velocity in the final 200m, significantly explained the probability of finishing 1st, 2nd or 3rd,” Prof McGreevy added.

“That said, it remains possible that whip use in the final stages of a race really does improve relative performance at a stage when all horses are slowing, but more frequent and sensitive methods of measuring velocity may be required to detect such a cause and effect linkage.” 

The authors conclude, “These data make whipping tired horses in the name of sport very difficult to justify.”

For more details see:

http://www.equinescienceupdate.com/articles/sfwrp.html

Equine Guelph survey research

Equine Guelph offer you the chance to influence their research and education programs so they meet the needs of the equine industry. 

Complete their survey and you can enter a draw for one of two gift certificates for an Equine Guelph online course of your choice (valued at $549.00) 

http://www.surveymonkey.com/s/industrysurvey_enews_1