NEW LAMINITIS STUDY

A new research project aiming to help horse owners reduce the impact of laminitis is being undertaken by the Animal Health Trust (AHT) in partnership with the Royal Veterinary College (RVC).

The study, which will extend over four years, is being funded by World Horse Welfare. It will take a closer look at management factors that may contribute to the development or recurrence of laminitis within the British horse and pony population. Through modifying these contributing factors, it is hoped that horse owners can significantly reduce the impact of this important welfare problem.

The AHT and RVC plan to create a website where owners from all over the country can register their horses and ponies and assist in the regular gathering of information related to potential risk factors for laminitis, over a period of two years.

This will help establish a timeline of events and gain a better understanding of the factors leading to laminitic episodes.

The study, to be conducted by PhD student Danica (Dee) Pollard, will follow-up on previous research conducted by Dr Claire Wylie in which factors such as rapid weight gain, increasing time since last deworming, box rest in the previous week and new access to grass in the past month increased the risk of laminitis.

Dr Wylie’s study also revealed that factors such as feeding of additional supplements and transport in the previous week were associated with a reduced risk of laminitis. 

These are factors that could all be changed by the owner, and this is why they are of particular interest to the new study.

Dee Pollard, based at the AHT, said: “This will be a very exciting opportunity for owners to be at the frontline of equine health research and contribute to a study which aims to provide evidence-based preventative strategies to combat laminitis.”

Horse owners interested in taking part in the research project are asked to register their interest via email to danica.pollard@aht.org.uk

Acceptability of smaller microchips

Although microchips are widely used for identifying horses throughout Europe, there is still some resistance to their use, with questions being raised about stress during implantation, inflammation at the site of implantation, and reliability of detection.

In response to this criticism, microchips that are even smaller have been developed. They may be less stressful to implant, but do they work as well? Recent work has looked at whether such chips are reliable and if their implantation causes signs of stress.

The study, carried out at the Brandenburg State Stud at Neustadt (Dosse), Germany, was  reported by Manuela Wulf and others in a recent edition of the Veterinary Record. Forty adult mares were implanted,  on the left side of the neck, with a reduced-size microchip (10.9×1.6 mm). (Conventional microchips are 11.4×2.2 mm). Three different scanners were used to detect the microchips  immediately, and on three further occasions up to 28 weeks after implantation.

The researchers found that scanners differed in their ability to read the microchips, although all scanners detected all chips on every occasion when scanned from the side of implantation. One scanner read all microchips successfully from both sides of the neck on four occasions up to 28 weeks after implantation.  Two other scanners detected all of the chips from the side of implantation, but were less successful reading from the “wrong” side of the neck.

Did the horses find the implantation procedure stressful? The researchers monitored heart rate, heart rate variability and saliva cortisol levels during the implantation process in twelve of the mares. They also recorded the same information while pressing at the implantation site with a cannula without penetrating the skin. So each mare acted as its own control. They found a slight increase in heart parameters in both chip implantation and controls, but no change in cortisol levels.

The report's authors conclude that reduced-size microchips are highly reliable for identification of horses. “Compared with conventional microchips, the reduction in size did not impair readability. Microchip implantation is no pronounced stressor for horses.”

For more details see:
Reduced-size microchips for identification of horses: response to implantation and readability during a six-month period.
Wulf M, Aurich C, von Lewinski M, Möstl E, Aurich JE.
Vet Rec. 2013 Nov 9;173(18):451.
 doi: 10.1136/vr.101824

Riding Arena Footing and Management Webcast

Ever wondered what's involved in providing a top quality arena surface, or wanted to know more about the materials to use?

Here's your opportunity. There's a free webcast on “Riding Arena Footing and Management” from MyHorseUniversity on November 26, 2013 at 7 PM ET.

Dr. Ann Swinker, Associate Professor in Equine Sciences, Penn State University and Horse Extension Specialist has been involved in the horse business for over 35 years. She will discuss the physical properties of the various footing materials that are available and the advantages and disadvantages. She will also consider the management of arena surfaces, the principles of maintenance and the signs that a surface needs to be changed or replaced.

You can register for the webcast now. Don't worry if you miss it; you can still catch it later, as it will be archived on the website and will continue to be available (free).

For more details go to ....

http://myhorseuniversity.com/resources/webcasts/ridingarenafooting

Benefit of targeted worming

Worming only those horses that need it can be cost effective, even taking into account the cost of performing faecal worm egg counts, according to research published in the Veterinary Record.

It is now widely acknowledged that a targeted approach to worm control is preferable to interval dosing regimes. Current recommendations are that only those horses carrying a moderate or high worm burden are treated; thus ensuring that worms are not exposed to anthelmintics needlessly.

Faecal worm egg counts (FECs) are used to determine which horses need (or don't need) treating. To many owners this may seem an unnecessary expense. However, recent work has shown that using FECs in this way helps reduce the overall cost of worming.

Hannah Lester, with colleagues at the Moredun Research Institute, and the Universities of Bristol, Liverpool and Edinburgh, monitored FECs at 3 monthly intervals over a nine month period. In all, 368 horses from 16 separate yards were involved in the study.

Horses with FECs greater than 200epg were treated, with pyrantel (in March and June) and ivermectin (in September). All horses received moxidectin/praziquantel in December.

The researchers compared the cost with that of a standard interval regime of two treatments with moxidectin and two of moxidectin and praziquantel - which is what had been common practice in the study population.

They  estimated the cost of the two approaches by using average prices for anthelmintic products and faecal egg counts that they obtained off the internet. Even allowing for the cost of faecal egg count reduction tests  (ie repeating the FEC after each treatment to check the anthelmintic had been effective)  they found that, over the year, there was an average saving per yard of £294.44.

They conclude: “these findings support the notion that targeting anthelmintic treatments at those individuals with strongyle FEC of 200epg or greater facilitates a reduction in selection pressure for anthelmintic resistance. Moreover, the results show that such a strategy has a high chance of reducing the financial cost compared with that associated with more traditional interval treatment regimens, and horse owners should, therefore, be discouraged from the view that it is cheaper to treat all horses prophylactically over time.”

Read more: equinescienceupdate.com

Emergency ventilation system developed

Respiratory or cardiovascular arrest in outdoor animals poses a huge challenge to veterinarians. Ventilation equipment is generally hard to operate and requires electricity and compressed air, and is not easily transportable. 

Anaesthesiologists at the University of Veterinary Medicine, Vienna (Vetmeduni Vienna) have developed an inexpensive device that can be used to ventilate large animals. They report that it is easy to transport and can save animal lives in emergencies.

In work recently published in  Equine Veterinary Education, the scientists confirm that their emergency ventilator is effective in horses. 

Yves Moens is Head of the Vetmeduni’s Clinical Unit of Anaesthesiology and Perioperative Intensive Care Medicine. He and his colleagues have long been concerned by the number of horses that die avoidable deaths because of the lack of a suitable ventilation device. The device they designed is similar to the bellows used to inflate air mattresses but has been adapted by the addition of a manually operated expiratory valve.

Although it can only provide 2.5 litres of air, the researchers believed that it would provide sufficient ventilation if the bellows were activated several times in quick succession. They tested this idea on five anaesthetised Haflinger horses during castration surgery and showed that gradual ventilation with the 2.5 litre pump was sufficient to keep the animals alive.

 “It improves the safety of large animals in the field, both during routine anaesthesia and in emergencies. It will also help veterinarians to provide emergency first aid in these circumstances and respect the guidelines for good practice", says Moens. “The respiratory pump is inexpensive and easy to use and will help veterinarians treat their patients in the field.”

Read more : equinescienceupdate.com

How accurate is thermography of horses’ legs?

Infrared thermography is increasingly being applied to investigate the cause of lameness in horses.  The equipment is easy to handle and the method is fast and safe, both for the animal and for the vet.  But is it accurate? 

Recent work by Simone Westermann at the University of Veterinary Medicine, Vienna shows that the technique is surprisingly tolerant of variation in the position of the equipment, i.e. how far from the horse and at what angle to the animal the infrared camera is held. 

In fact, the results were almost completely unaffected by 20° changes in camera angle and increases of up to 50 cm in the distance of the camera from the animal.  At a distance of 1m from the horse a 20° change in camera angle corresponds to about 35 cm.  This represents the effective horizontal tolerance in positioning of the camera.  As Westermann says, “vets should have little difficulty in remaining within this limit, so the method is applicable in practice”. 

Surprisingly, the results showed that horses’ left and right forelimbs show minor differences in temperature and Westermann cautions that “it might be important to take these into account before reaching a final diagnosis.”

The technique is thus reliable and robust, at least in terms of variation in where the camera is located. 

However, it turned out to be extremely sensitive to even very gentle drafts.  A wind speed of less than 1 m/s causes a drop in measured temperature of about 0.6°C, while winds of 1.3-2.6 m/s cause a drop of 1.5°C and winds of 3-4 m/s cause a drop of 2.1°C.  The discrepancies are more than sufficient to lead to a wrong diagnosis, although even the highest wind speed tested is hardly perceptible:  it would barely cause leaves on trees to move.

Westermann is keen to note the relevance of her work for vets who work on horses.  As she says, “It turns out that it is not too important to be sure that the camera is in exactly the correct position before taking measurements.  But it is essential to perform thermography on horses in a room that is completely free of draughts.  If you don’t, your diagnosis will be completely unreliable.”

More information : equinescienceupdate.com

Antibacterial action of honey

Wounds to the lower limbs of horses can prove challenging to manage.  Recently there has been a growing interest in the use of honey in such cases.

Not all honey is the same. Its antibacterial quality depends on the type of honey and the conditions under which it was harvested and processed. Most honey contains hydrogen peroxide, which has antibacterial properties. Some types of honey contain other active components. For example, manuka honey is believed to have antibacterial properties due to high concentrations of methylglyoxal, a compound usually found in only low quantities in other types of honey.

Manuka honey, produced by bees foraging on manuka plants (Leptospermum scoparium), native to Australia and New Zealand, has been the subject of considerable research. Honey from other sources is often used in practice, but there has been little research into how effective it is.

Researchers at the University of Glasgow have been examining various different types of shop-bought honey to determine if they were free from bacterial contamination and suitable for use on equine wounds. They also investigated the effect of various examples of uncontaminated honey on the growth of equine pathogens, and  found that, in laboratory tests, certain varieties of honey are able to inhibit bacterial growth even at very low concentrations.

They found that many commercial sources of honey were contaminated with bacteria. The most commonly identified contaminating organism was Bacillus spp. However, potentially pathogenic organisms  (Proteus and Enterobacteraceae) were identifed in two honey samples.

Uncontaminated honey samples were subjected to further investigation to assess their antibacterial properties. Eight of the eleven samples tested were effective against all 10 bacterial isolates at concentrations from 4 to 16%. Overall, medical grade Manuka honey and a locally produced heather honey performed best.

The researchers conclude that many honeys have antimicrobial properties, and may be effective in the treatment of wound infections. They note that the concentrations at which honey samples inhibited microbial growth were much lower than is likely to occur at the surface of an infected wound treated with honey.

However, they advise that “the use of shop-bought honey on wounds should be avoided, as contamination with potentially pathogenic microbes appears to be common. Honey sourced within the UK is as, and in some cases more, effective than medical grade honey sourced in New Zealand.”




Read more at equinescienceupdate.com/articles/aah.html

New laminitis research findings

Laminitis continues to be a significant welfare problem of horses and ponies, causing widespread suffering. Investigations into the underlying causes and disease processes involved in the condition are ongoing.

The benefits of  feeding a balanced diet alongside appropriate forage, grazing restriction and regular low intensity exercise whenever clinically possible in the management of laminitis prone horses and ponies have been highlighted by new research.

Four separate studies have shed new light on the possible role of grass fructan in the development of laminitis; the influence of water temperature when soaking hay to reduce the water-soluble carbohydrate content; a possible link between recurrent laminitis and reduced anti-inflammatory capacity, and the potential anti-inflammatory benefits of exercise.

Read more at equinescienceupdate.com

Controlling forage intake with hay nets

Horses have evolved to spend much of the day grazing. However, modern systems of horse management often restrict the time available. This may contribute to problems such as gastric ulceration and can result in behavioural problems.

Sometimes it is desirable to reduce the intake of roughage – either to make the horse's ration last longer, or to limit its overall intake.

Recent research from the University of Minnesota shows that using hay nets with smaller holes is effective for limiting the rate of roughage ingestion in horses.

Eight horse were involved in the study. They were were housed in individual box stalls, and fed hay off the floor (control treatment) or from hay nets with one of three different sized holes. The mesh size ranged from 15.2cm (large), to 4.4cm (medium) and 3.2cm (small).

During the trial period, hay was available for two four-hour periods each day.

Horses were allowed to become accustomed to each type of net for 2 days, before intake was recorded over three days. They then had two days of a wash out period during which they were as a group in an outdoor paddock.

The researchers found a significant difference in the rate of consumption between all treatment groups. Horses fed hay off the floor (control) consumed hay at the rate of 1.49kg/hr. Consumption of hay from hay nets was 1.33kg/hr, 1.11kg/hr, 0.88kg/hr for large, medium and small sized holes respectively.

They found no difference between the large mesh net and control for the amount of hay consumed (both 95%% of hay offered); but medium and small hay nets restricted hay intake to 89% and 72% respectively.

They conclude that their results demonstrate that the medium and small sized nets were effective in decreasing both rate and amount of forage consumed by adult horses.





More information at equinescienceupdate.com