A survey of horse owners in Britain has highlighted issues around animal traceability in the country should there be an infectious disease outbreak.
The researchers said their findings, published in the journal, BMC Veterinary Research, illustrated the difficulties which exist with national horse traceability in Britain, despite the operation of the National Equine Database, which ran from 2006 to 2012, and the horse passport system.
Glasgow University researchers Lisa Boden, Tim Parkin, Julia Yates, Dominic Mellor, and Rowland Kao said contingency planning for potential equine infectious disease outbreaks relied on accurate information on horse location and movements to estimate the risk of spread of disease.
An online questionnaire was used to obtain unique information linking owner and horse location to characteristics of horse movements within and beyond Great Britain.
Boden and her colleagues said the online survey yielded a strong response, providing more than four times the target number of 1000 respondents living in all parts of Britain.
The 4298 respondents on which the analysis was based owned or were responsible for 17,858 horses.
Analysis indicated that horses who were kept at livery yards and riding schools were likely to be found in urban environments, some distance away from the owner’s home and vaccinated against influenza and herpes virus.
Survey respondents were likely to travel greater than 10 miles to attend activities such as eventing or endurance, but 58.6 per cent were also likely to travel and return home within a single day.
“This may affect the geographical extent and speed of disease spread, if large numbers of people from disparate parts of the country are attending the same event and the disease agent is highly infectious or virulent,” the researchers said.
“The greatest risk for disease introduction and spread may be represented by a small proportion of people who import or travel internationally with their horses.
“These respondents were likely to have foreign horse passports … making the location of these horses untraceable.”
Within Britain, these horses integrate with the local equine population during competition and breeding activities. If a local population became infected this would be an efficient mechanism for spread of disease due to the interconnectedness of the industry, the researchers said.
“However, these movements for competition and breeding purposes are reasonably infrequent and over greater distances and, fortunately, are well-recorded by the relevant competition organisations. As such, these horses are likely to be well-managed and under vigilant disease surveillance.”
The researchers said the introduction of mandatory horse passports in 2005 was viewed as an opportunity to improve horse traceability.
However, collecting accurate data on horse location and movements remained a problematic and important issue, particularly with respect to disease control.
Since 2006, the National Equine Database had received data on all equidae issued with a passport from any of the 80 passport-issuing organisations in Britain.
However, in September 2012, funding for the database ended. Plans to continue a centralised equine database have not been confirmed.
“There are several independently collected sources of data on horse location in Great Britain, but none is considered a ‘gold standard’ being representative of the whole equine population,” the authors said.
The researchers said location information was well-documented on horses registered with highly regulated organisations within the equestrian industry, but there was a lack of information on unregistered horses used for leisure activities or as pets, even though these horses may account for up to 60 per cent of Britain’s horse population.
“These least-well regulated animals may be most important in an outbreak, precisely because they are difficult to find and their impact on disease transmission unknown.”
Analysis showed that respondents usually transported horses in their own vehicles (64.5 percent); 14.8 percent shared their vehicles or others’ vehicles (31.9 percent) to transport horses from the same or different premises.
In the year preceding the questionnaire, most respondents would drive two hours or less to attend local events (90.6 percent) or to obtain horse care (84.1 percent). Most respondents – 70.5 pecent – would drive three hours or less to attend national events.
A small proportion of respondents, 6.3 percent, travelled with their horses internationally and/or imported horses from Belgium, Ireland, Germany, Spain and Poland.
“Compared to those who did not travel internationally, horse owners who did so were three times more likely to have at least one horse with a foreign passport than a British-issued horse passport.
“They were also more likely (than not) to be a riding instructor/professional equestrian, a breeder or involved in the thoroughbred industry and participate in activities such as breeding, show jumping or endurance.
“Consistent with previous findings, this study showed that horse-keeping on livery yards or riding schools was more likely to be near urban, semi-urban or industrial areas.
“In theory, these types of premises may pose the greatest risk for disease transmission due to large numbers of horses at the same site owned and cared for by different people.
“Although this study indicates that vaccination coverage for prevalent infectious equine diseases such as influenza virus, herpes virus and tetanus was not 100 percent, it was better than previously reported and horse owners associated with livery yards and riding schools were more likely than not to vaccinate for these diseases.
“Vaccination coverage may be a proxy measure for biosecurity awareness but horse owners need to appreciate the risks associated with keeping horses at these types of premises, particularly with regard to spread of emergent and exotic viruses for which there are no vaccines available.”
Respondents were likely to travel far to attend infrequent activities such as eventing or endurance. Most respondents would travel to and from an event in a single day.
“This may affect the geographical extent and speed of disease spread, if large numbers of people from disparate parts of the country are attending the same event and the disease agent is highly infectious or virulent.
“However, should a disease outbreak occur, the survey data suggest that only a small proportion of horses would be out of position (i.e. not at their premises of origin), should lengthy movement restrictions be implemented.
“Nevertheless, even if this proportion represented only 0.005 percent of the total Great Britain horse population, this would result in as many as 5000 horses being ‘out of position’.
“This is a significant consideration for policy makers when planning for disease control for horses compared to livestock.”
The authors said results of the study illustrated the difficulties that still existed with national horse traceability in Britain.
“This study also demonstrates that an online approach could be adopted to obtain important demographic data on Great Britain horse owners on a more routine and frequent basis to inform decisions or policy pertaining to equine disease control.
“This represents a reasonable alternative to collection of Great Britain horse location and movement data given that the NED no longer exists and there is no immediate plan to replace it.”
Lisa A Boden, Tim DH Parkin, Julia Yates, Dominic Mellor and Rowland R Kao
An online survey of horse-owners in Great Britain
BMC Veterinary Research 2013, 9:188 doi:10.1186/1746-6148-9-188