Ticks wanted dead or alive!

The Western College of Veterinary Medicine (WCVM) in Saskatchewan, Canada, have launched a study into tick borne disease in the area.

A research team headed by Dr. Katharina Lohmann has initiated a pilot study into the prevalence of equine granulocytic anaplasmosis (A. phagocytophilum infection) and Lyme disease (Borrelia burgdorferi infection) in Saskatchewan horses. Both bacteria are transmitted in Canada primarily by the black legged tick, Ixodes scapularis. 

Curently, these infections are not common in Canada. There have been only three cases of anaplasmosis reported in horses in the country, one of which was found in Saskatchewan in 2010. 

Dr Lohmann explains that Ixodes scapularis is not thought to be established in Saskatchewan, but individual ticks may be carried in from different areas of the country and from the U.S. by migrating birds.

The first phase of the study will examine blood samples collected from horses in Saskatchewan, Manitoba and Ontario. The research team expect to find antibodies to A. phagocytophilum or B. burgdorferi in about two per cent of horses.

In order to better understand which species of ticks are relevant to horses, the researchers are asking veterinarians and horse owners to submit any ticks found on horses within Saskatchewan.

So far, the species of tick submitted to the survey includes Dermacentor albipictus (winter or moose tick), Dermacentor andersoni (Rocky Mountain wood tick) and Dermacentor variabilis (American dog tick).

The WCVM research team would be pleased to receive ticks of any life stage (including larva, nymph and adult stages) and are actively seeking tick submissions over the next two years (2011-2013).

More details of the tick survey, including how to submit ticks found on horses, are available at:

http://www.usask.ca/wcvm/veterinarians/equine_ticks.php

 

Unexpected outcome of Hendra virus cases

A survey of equine veterinary practices in Queensland Australia has shown that veterinarians are stopping doing equine work because of the risks posed by Hendra virus.

Hendra virus (HeV) infection primarily affects fruit bats, but was first reported in horses in 1994. During the initial outbreak 14 horses died. Seven other horses were shown to have been infected and were humanely destroyed.

Human infections, although uncommon, most  often affect people in contact with horses. Of seven cases of human HeV infection, five have involved equine veterinary personnel conducting post mortem  or endoscopic examinations. In three cases the infection was fatal.

A study, published in Emerging Infectious Diseases, explored the issues faced by  staff of equine veterinary practices relating to HeV infection-control and workplace health and safety.

 

The research team from James Cook University, in Townsville, Queensland, was led by Diana Mendez. They interviewed 21 veterinarians and other staff from 14 equine or mixed practices.

 

They found that twelve of twenty veterinary professionals  (60%) had dealt with one or more cases of HeV infection; seven of them (35%) had dealt with a confirmed case.

One finding that they had not expected was that some veterinarians had given up equine practice because of HeV. Four of 18 vets interviewed said they had stopped doing equine work, and 44% knew of one or more colleague who had stopped doing equine work in the previous year. Concerns over personal safety and legal liability related to HeV were given as the main reason for the decision to leave equine practice.

A vaccine against HeV is being developed. The availability of such a vaccine would go some way to calm the fears of those working in the Australian equine sector.

 

Read more at: www.equinescienceupdate.com

 

Equitation science - the road ahead

 The International Society for Equitation Science celebrates its 10th anniversary this year with a conference in Edinburgh, Scotland. Two days of talks and discussions on the science of horse riding and horse training are planned, followed by a practical day at the Scottish National Equestrian Centre

Details of the scientific program are now available on the ISES website...  

http://www.ises-uk2012.com/programme.htm

How horses recognise humans

Research just published from the University of Sussex demonstrates that domestic horses use a sophisticated cognitive system to identify individuals of species other than their own.

Drs Leanne Proops and Karen McComb, of the School of Psychology's Mammal Vocal Communication and Cognition Research Group, had already shown that horses can combine auditory and visual information to recognise each other.

In their latest research they demonstrated that horses also use this system to distinguish between the different humans they know.

Dr McComb explained: “When we hear a familiar voice we form a mental picture of who spoke. We match visual and auditory cues to recognise specific individuals. Previously we showed that horses also identify other horses cross-modally.

“We now demonstrate how flexible this ability is by showing that horses can also recognise humans in this way, despite people looking and sounding very different to themselves.”

The study was carried out using domestic horses that were accustomed to several different handlers.

Firstly the researchers tested where the horse would look when two voices - one familiar, one unfamiliar - were played from a hidden loudspeaker, either side of which stood the familiar and unfamiliar person.

They found that the horses responded more quickly and looked for longer and more often at the familiar human compared with the stranger when played their voice. They were significantly better at making this match when the familiar person was on the right of their visual field (indicating that the left hemisphere of the brain is involved in this processing).

The researchers then tested how the horses would perform the more complex task of distinguishing between two familiar voices.

This time, the horses were able to match a specific familiar voice to its human handler. This indicates, say the researchers, that the sight of the handler activated a multi-modal memory of that specific individual, allowing each horse to match the sight of a particular person with the sound of their voice.

Horses likely use this recognition strategy naturally to identify numerous individual people in their day-to-day lives.

Read more at: www.equinescienceupdate.com

Clydesdale bog spavin survey

Clydesdale horses would benefit from their owners knowing more about the likely causes of bog spavin, the chronic fluid distension of the tarsocrural (hock) joint.

A survey of Clydesdale owners in the USA and the UK found that most knew of the condition, but were often unaware of its possible significance.

Of the 93 5  horses included in the survey, 10% were reported to show signs of bog spavin. Over half of the affected animals first showed signs of bog spavin before they reached one year of age. This is significant as it coincides with the time when osteochondrosis tends to occur.

Osteochon drosis, a disorder of bone development which results in damage to the articular cartilage, is the most common cause of long term joint swelling in young horses showing little or no lameness. If untreated, the condition may eventually result in osteoarthritis and persistent lameness.

The owners' approach to the condition differed on opposite sides of the Atlantic. In the UK, nearly half of the affected horses were not investigated at all, whereas in the USA over 75% received some investigation – ranging from physical examination by the owner, yard manager or veterinarian, to more specialised techniques.

Radiographic examination was performed on 37.7% of affected horses in the USA , but on just 12.2% in the UK.

Some of the cases of bog spavin identified in the survey could be due to undetected osteochondrosis. The report's authors suggest that a radiographic survey of Clydesdale horses is warranted to establish the true extent of osteochondrosis of the hock joint.

They argue that if more owners knew about the possible causes of bog spavin they might be more likely to investigate and thus identify those horses with osteochondrosis. Arthroscopic surgery could then be offered to appropriate cases to reduce the risk of osteoarthritis.

Read more at www.equinescienceupdate.com