Saturday, February 25, 2023

Can you help in a study to monitor arthritic pain?

(c) Silviu-Florin Salomia
Do you have an arthritic horse?  Could you spare a little time to take part in a study to validate
the use of a questionnaire for monitoring signs of chronic pain in horses with osteo-arthritis. 

Osteoarthritis (OA) is a major cause of chronic pain in horses yet it remains an under-recognized and under-treated condition. Despite its common association with advanced age, it can also affect young horses. In addition to being painful, OA can severely limit a horse's athletic career, and impact the bond between horse and owner if the condition limits a horse's ability to be ridden.


Diane Howard, PhD, MSc., a graduate of the Equine Science Master's program at the University of Edinburgh, has developed a 15-question survey based on interviews with horse owners whose animals suffer from chronic osteoarthritic pain.


The study will evaluate the questionnaire's efficacy in assisting owners to identify and monitor behavioural indications of pain in their horses.


Initial results,presented at the Horses Inside Out conference, are promising, but additional participants are required. To date, people completing the questionnaire have found it to be both helpful and straightforward to complete, with all participants able to finish it in less than five minutes.


The research, in collaboration with Dr. Janny de Grauw, from Utrecht University in the Netherlands, is funded by the Morris Animal Foundation.


“Many horses may deal with pain that is not recognized, particularly in its early stages,” said Dr. Janet Patterson-Kane, Morris Animal Foundation Chief Scientific Officer. “Giving their caregivers effective tools for detection, monitoring and decision-making has the potential for significant animal welfare impact.”


For more details, and to take part, please contact Diane Howard, at:


Why do horseflies avoid stripes?


(c) Martin How
Researchers at the University of Bristol have discovered the reason why horseflies tend to avoid attacking individuals with stripes, as opposed to those with big, solid dark patches. 

Their findings show that stark black-and-white contrasts and small dark patches are particularly
effective in preventing horsefly attack. Specifically, these features eliminate the outline of large, single-colour dark patches, which horseflies find attractive at close range. 


The team suggest that the thin back stripes serve to minimise the size of local features on a zebra that are appealing to the biting flies.


The research was led by Professor Tim Caro and Dr Martin How both from the University of Bristol’s School of Biological Sciences. An open access report of the work is published in the Journal of Experimental Biology.


 Prof Caro explained: “We knew that horseflies are averse to landing on striped objects - a number of studies have now shown this, but it is not clear which aspects of stripes they find aversive.


“Is it the thinness of the stripes? The contrast of black and white? The polarized signal that can be given off objects? So, we set out to explore these issues using different patterned cloths draped over horses and filmed incoming horseflies.”


The team found that tabanid horseflies are attracted to large dark objects in their environment but less so to dark broken patterns. All-grey coats were associated with by far the most landings, followed by coats with large black triangles placed in different positions, then small checkerboard patterns in no particular order. In another experiment, they found contrasting stripes attracted few flies whereas more homogeneous stripes were more attractive.


Professor Caro added: “This suggests that any hoofed animal that reduces its overall dark outline against the sky will benefit in terms of reduced ectoparasite attack.”


The team found little evidence for other issues that they tested, namely polarization or optical illusions confusing accurate landings such as the so-called ‘wagon-wheel effect’ or ‘the barber-pole effect’.


They conclude: “Our working hypothesis now is that horseflies are attracted to equid hosts owing to a combination of odour at a distance, then size of the animal contrasted against the sky or vegetation at a middle distance. But at close range, where they can no longer see the body's outline, flies make a visual switch to local features. If these are small dark objects contrasted against a light or white background, the horsefly no longer recognizes this as a host target and veers away. The contrast of stripes and their relatively small size are therefore the key elements of how stripes operate to thwart fly landings.”


Now the team want to determine why natural selection has led to striping in equids - the horse family - but not other hoofed animals.

Professor Caro added: “We know that zebra pelage – fur - is short, enabling horsefly mouthparts to reach the skin and blood capillaries below, which may make them particularly susceptible to fly annoyance, but more important, perhaps, is that the diseases that they carry are fatal to the horse family but less so to ungulates. This needs investigation.”


For more details, see:


Why don't horseflies land on zebras?

Tim Caro, Eva Fogg, Tamasin Stephens-Collins, Matteo Santon, Martin J. How

J Exp Biol (2023) 226 (4): jeb244778.

Survey: medicines and horse health in Wales

(c) Miles Haegebaert
Horse owners across Wales are invited to take part in a survey: “Understanding Welsh horse
owner perceptions of medicines use and horse health care.”

The survey is run by scientists at Aberystwyth University as part of the Arwain DGC (Responsible Antimicrobial Use) project. Arwain DGC aims to prevent the spread of antimicrobial resistance (AMR) in animals and the environment in Wales. 


By improving productivity, animal health and welfare through new and innovative technology and ‘good practice’, the goal is to reduce the need to use antimicrobials such as antibiotics.


It is hoped that the survey will bring about a greater understanding of the how Welsh horse owners view medicine usage and aspects of horse health care. Lead researchers are Rebekah Stuart or Alison Bard.


“We hope this study will generate information that will help target future research, support and funding within the Welsh equine sector, as currently very little is known about Welsh horse owners’ views on these topics.”


“Our questions will explore how you view your relationship with your horse or horses, how they receive husbandry and health care and how you interact with your vet and other individuals regarding medicines use.”



For more details, and to complete the survey, go to:

Friday, February 17, 2023

Evidence that Vikings brought horses across the North Sea

Credit : Jeff Veitch Durham University
 Recent research claims to have found the first solid evidence that Scandinavians brought horses, dogs and other animals across the North Sea with them as early as the ninth century AD.

Vikings, who lived in modern-day Norway, Sweden, and Denmark, have a reputation as skilled raiders and warriors. As seafaring people, they travelled extensively from the late 8th to the early 11th centuries, establishing settlements in various parts of Europe and the North Atlantic.


It is likely that they acquired horses through conquest and raids. However, a study of cremated bones found at an archaeological site in the English midlands suggests that at least some of their horses had been brought with them from Scandinavia.


The findings are published in the scientific journal PLOS ONE.


Lead author Tessi Löffelmann, a doctoral researcher jointly working in the Department of Archaeology, Durham University, and the Department of Chemistry, Vrije Universiteit Brussels, said: “This is the first solid scientific evidence that Scandinavians almost certainly crossed the North Sea with horses, dogs and possibly other animals as early as the ninth century AD and could deepen our knowledge of the Viking Great Army.”


“Our most important primary source, the Anglo-Saxon Chronicle, states that the Vikings were taking horses from the locals in East Anglia when they first arrived, but this was clearly not the whole story, and they most likely transported animals alongside people on ships.”


The work was a collaboration between academics at the Universities of Durham and York in the UK, and the Vrije Universiteit Brussel, in Belgium. 


They explain: “The barrow cemetery at Heath Wood, Derbyshire, is the only known Viking cremation cemetery in the British Isles. It dates to the late ninth century and is associated with the over-wintering of the Viking Great Army at nearby Repton [ in present day Derbyshire] in AD 873–4.”


Fragments of cremated bone from the site were available for analysis: two adult humans, a child and a horse, dog and pig.


But how to tell where these cremated bony fragments originated?


Strontium analysis helps provide the answer. Strontium (Sr) is an element, related to calcium, that is taken up by plants, which are then eaten by animals. The ratio of strontium isotopes in the soil varies from one geographical location to another. 


Because strontium is so like calcium, it is taken up by the bone. The ratio of strontium isotopes in the bone reflects that of the soil of the area in which the animal lived.


The researchers explain: “The Sr isotope ratios (87Sr/86Sr) from the bones and teeth of an individual, who grows up while ingesting plants from the immediate surrounding area, should reflect the local biologically available Sr  (BASr). By measuring these ratios in plants from the ‘local area’, it is possible to define the local BASr and its variations around the site.”


Strontium ratios in one of the adults and the child showed that they could have been from the area local to the Heath Wood cremation site.


But the remains of the other adult and all three animals – a horse, a dog and what the archaeologists say was possibly a pig – had strontium ratios normally found in the Baltic Shield area [the geological region comprising Norway, Sweden, Finland, and parts of Russia].

As the human and animal remains were found in the same cremation pyre, the researchers believe the adult from the Baltic Shield region may have been someone important who was able to bring a horse and dog to Britain.


Professor Julian Richards, of the Department of Archaeology, University of York, who co-directed the excavations at the Heath Wood Viking cemetery, said: “The Bayeux Tapestry depicts Norman cavalry disembarking horses from their fleet before the Battle of Hastings, but this is the first scientific demonstration that Viking warriors were transporting horses to England two hundred years earlier.


“It shows how much Viking leaders valued their personal horses and hounds that they brought them from Scandinavia, and that the animals were sacrificed to be buried with their owners.



For more details, see:


Sr analyses from only known Scandinavian cremation cemetery in Britain illuminate early Viking journey with horse and dog across the North Sea

Tessi Löffelmann , Christophe Snoeck,  Julian D Richards , Lucie J Johnson,  Philippe Claeys , Janet Montgomery 

PLoS One (2023) Feb 1;18(2):e0280589.

Wednesday, February 15, 2023

Possible new approach to DDSP treatment

 Intermittent dorsal displacement of the soft palate (iDDSP) is a cause of exercise intolerance
and poor performance
, particularly in horses involved in strenuous activities such as racing. 

In DDSP, the soft palate, which should fit snuggly around the larynx, flips out of position and obstructs the airway, limiting the horse’s ability to breathe.


Various techniques have been used to treat the condition; ranging from the conservative (such as tongue straps, crossed nose bands, glycerine on back of the tongue, treatment of other respiratory problems), to surgery.


Laryngeal tie forward (LTF) is a commonly used surgical treatment for the condition with reported success rates up to 80%.  Prosthetic sutures are placed between the thyroid cartilage and the basihyoid bone, to tie the larynx forward and fix it in place to prevent the soft palate dislocating and blocking the airway during exercise.


The operation is typically carried out under general anaesthetic, which involves some risk and expense. It has been suggested also that recovery from general anaesthetic may contribute to failure of the prosthesis (sutures). 


Clinicians at the University of Queensland School of Veterinary Science have described a series of cases in which they carried out the operation in sedated standing horses.


Natasha E. Lean and colleagues reported the work in a recent issue of Veterinary Surgery.


They performed Standing LTF in five experimental (normal) horses and five clinical cases with iDDSP. The procedure was carried out under endoscopic guidance, with the horses sedated and the surgical site desensitised with local anaesthetic. No major complications were encountered.


The response to surgery was assessed using radiography, and endoscopy. 

The authors conclude that standing LTF is “feasible, mitigates the risk of general anesthesia related complications and reduces cost.”



For more details, see:


Laryngeal tie-forward in standing sedated horses

Natasha E Lean, Albert Sole-Guitart, Benjamin J Ahern 

Vet Surg (2023) Feb;52(2):229-237.

 doi: 10.1111/vsu.13920 

Wednesday, February 08, 2023

Advances in imaging distal limbs

PET, CT and MRI images of navicular / middle phalanx. (c) EVJ
Radiography has been used for imaging horses’ legs for over a hundred years. Recent technological advances have
delivered new imaging modalities.

The publications Veterinary Radiology & Ultrasound (VRU), Equine Veterinary Education (EVE) and the Equine Veterinary Journal (EVJ) have combined forces to celebrate the evolution in equine imaging with a free special collection to reflect some of the most significant advances in distal limb imaging from the past five years.


Advances in Imaging of the Equine Distal Limb 2017–2022 comprises a total of 20 papers which have been selected by Mathieu Spriet, Ann Carstens and Tim Mair. It is accompanied by a comprehensive editorial from the EVJ summarising the major historical technological developments in imaging of the foot and fetlock, embracing all the modalities.


The evolution of computed tomography (CT) allows the imaging of the distal limb without anaesthesia. CT scanners are also now used in surgery rooms bringing significant progress in orthopaedic surgery.  Six papers look at advances in CT including addressing some of the challenges of the ring design of this modality.


Positron emission tomography (PET), the latest modality to be introduced to equine imaging, has opened a whole new field of possibilities for bone and soft tissue imaging in racehorses and sport horses. Five papers look at how PET brings functional information to the table, allowing early detection of abnormalities before the occurrence of structural changes and distinguishing between active and inactive lesions when structural changes are present.


MRI has been a mainstay in orthopaedic imaging for many years; six important studies are included in the collection and show how the optimisation of scanning techniques is constantly improving this modality. 


Ultrasound is steadily improving; one of the papers looks at the important technical evolution involving the imaging of limbs in non-weight bearing position as well as under the classic weight bearing position.


Radiographs remain the most commonly used imaging technique, despite the modality being more than 100 years old. One of the papers confirms why radiographs remain a valuable imaging tool.


The role of scintigraphy has decreased in the past 20 years with the emergence of advanced cross-sectional imaging, but it remains an essential tool especially for comparative imaging studies. One of the papers examines agreement between scintigraphy and MRI to identify the source of foot pain.


“The content of this virtual issue represents an amazing amount of new knowledge that with no doubt will contribute to improve equine welfare and safety,” said Mathieu Spriet. “With the increase availability and versatility of all the imaging modalities, the knowledge base appears to increase exponentially. We are very excited to see what the next five years will bring. We hope the readers will enjoy consulting this collection as much as we enjoyed putting it together.”


“During the past five years close to 100 equine imaging papers have been published between EVJ, VRU and EVE, covering a wide variety of topics,” said Professor Celia Marr, Editor of the EVJ. “The EVJ is proud to have been able to work collaboratively to bring this definitive distal limb imaging collection to life, giving clinicians easy access to some of the most pertinent work in this area.”


The virtual issue is free for 12 weeks and can be found at