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Vets identify genetic cause of fatal condition in Thoroughbreds
EFIH is an invariably fatal condition that causes involuntary contraction of muscles and seizures in Thoroughbred foals.
Study of affected foals reveals a mutation in the RAPGEF5 gene.

A genetic cause of equine familial isolated hypoparathyroidism (EFIH) in Thoroughbreds has been identified by researchers at the UC Davis School of Veterinary Medicine.

Researchers say their finding, reported in PloS Genetics, marks the first genetic variant for hypoparathyroidism identified in any domestic animal species. It is also the first widely available genetic test for Thoroughbreds.

“For Thoroughbred owners and breeders, the loss of a foal has tremendous economic and emotional impacts,” says first author Victor Rivas. “It is important to promote safe and strategic breeding habits by actively breeding horses genetically screened not only for EFIH but for other diseases that may impact quality of life.”

EFIH is is an invariably fatal condition that causes involuntary contraction of muscles and seizures in Thoroughbred foals. Foals with the disease typically have low levels of parathyroid - a hormone that controls calcium levels - and often die or are euthanised owing to poor prognosis.

In the study, researchers identified an autosomal recessive mode of inheritance and performed whole-genome sequencing of two affected foals. They found that a mutation in the rap guanine nucleotide exchange factor 5 (RAPGEF5) gene was present in two copies in both foals.

The team further analysed the variant and demonstrated loss-of-function of the RAPGEF5 protein leading to aberrant development. Their study concludes that RAPGEF5 could play a key role in the derivation of the parathyroid gland during development.

“The next steps are to assess the allele frequency in a large population of randomly selected Thoroughbreds,” explained study lead Dr Carrie Finno. “Additionally, we have discussed collaborating with Dr Nathan Slovis at Hagyard Equine Medical Institute in Kentucky to test for the variant in cases of ‘sudden death’ in Thoroughbred foals.”

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RCVS launches photo contest for Mental Health Awareness Week

News Story 1
 The RCVS Mind Matters Initiative (MMI) is holding a photo competition for Mental Health Awareness Week to highlight the link between the natural world and wellbeing.

Mental Health Awareness Week (10-16 May) aims to encourage people to talk about their mental health and reduce the stigma that can prevent people from seeking help. This year's theme is nature - notably the connection between the natural world and better mental health.

The RCVS is calling on aspiring photographers to submit a photo on this theme to Lisa Quigley, Mind Matters manager, at with a short explanation about their submission and why nature improves their mental health and wellbeing.  

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WSAVA to host free webinar on illegal online puppy trade

The World Small Animal Veterinary Association (WSAVA) has announced a free webinar to update veterinary professionals across Europe about the illegal online puppy trade. Taking place on Tuesday, 25 May, the webinar will also discuss the importance of the new EU Animal Health Law to help prevent illegal pet sales and make sellers accountable for their actions.

WSAVA chair Dr Natasha Lee said: "Veterinary professionals regularly have to deal with the repercussions of illicit breeding and trading when presented with clinically ill and sometimes dying puppies and distraught owners. Our webinar will equip veterinarians in Europe with the knowledge to play their part in upholding the new legislation and to contribute to new solutions for regulating the online puppy trade."

For more details visit