Your data on MRCVSonline
The nature of the services provided by Vision Media means that we might obtain certain information about you.
Please read our Data Protection and Privacy Policy for details.

In addition, (with your consent) some parts of our website may store a 'cookie' in your browser for the purposes of
functionality or performance monitoring.
Click here to manage your settings.
If you would like to forward this story on to a friend, simply fill in the form below and click send.

Your friend's email:
Your email:
Your name:
Send Cancel

Inbreeding leads to thoroughbred pregnancy loss, study finds
Inbreeding is commonly used in the breeding of livestock.

It contributed to mid and late-term pregnancy loss, but not early loss.

A new study has revealed that genomic inbreeding contributes to mid and late-term pregnancy loss (MLPL) in thoroughbred horses.

However the research, conducted by Royal Veterinary College (RVC), found that it had no contribution to early pregnancy loss (EPL).

The study saw researchers from RVC, in collaboration with Cornell University, analyse DNA samples from 189 horses, including a control group. The scientists studied the metrics of thoroughbred pregnancies that were lost in early, mid and late gestation.

Findings revealed thoroughbred pregnancies that were lost in mid and late gestation had significantly higher inbreeding metrics than in UK thoroughbred adults. In contrast, pregnancies which were lost early in gestation had no significant difference in inbreeding metrics to thoroughbred adults.

Inbreeding is commonly used in the breeding of livestock, to ensure that newborns carry desirable traits.

However, excessive inbreeding can increase the likelihood of uncovering homozygous recessive genotypes, which can be associated with a higher risk of retained placenta and lower semen quality in horses.

Five to 10 per cent of equine pregnancies result in pregnancy loss in the early stage of gestation. A further seven per cent are lost between Day 70 of gestation and 24 hours post parturition.

The findings of this study, which is the first to explore the effects of genomic inbreeding levels on late term pregnancy loss in horses. The researchers say that this highlights the importance of informed equine mating decisions to minimise the risk of miscarriages in thoroughbreds.

Dr Jessica Lawson, Alborada Trust Research Fellow at the RVC, said: “The take home from our work should be to carefully consider breeding choices that involve mating of highly related individuals as, ultimately, this may increase the chance of the foal inheriting mutations which may not be compatible with life.

“We are already working on the next step, looking to identify these changes so more specific advice can be provided in the future.”

The full study can be found in the Equine Veterinary Journal.

Image © Shutterstock

Become a member or log in to add this story to your CPD history

Charities' XL bully neutering scheme closes

News Story 1
 A scheme that helped owners of XL bully dogs with the cost of neutering has closed to new applications due to high demand.

The scheme, run by the RSPCA, Blue Cross, and Battersea, has helped 1,800 dogs and their owners after XL bullies were banned under the Dangerous Dogs Act.

In England and Wales, owners of XL bully dogs which were over one year old on 31 January 2021 have until 30 June 2024 to get their dog neutered. If a dog was between seven months and 12 months old, it must be neutered by 31 December 2024. If it was under seven months old, owners have until 30 June 2025.

More information can be found on the Defra website. 

Click here for more...
News Shorts
Avian flu cattle outbreak spreads to tenth US state

Cattle in two dairy herds in Iowa have tested positive for highly pathogenic avian influenza (HPAI), making it the tenth state in the USA to be affected by the ongoing outbreak of the disease in cattle.

Since March 2024, more than 80 herds across the USA have been affected by the virus and three dairy workers have tested positive. Authorities have introduced measures to limit the spread of the virus and farmers have been urged to strengthen their biosecurity protocols.

Mike Naig, Iowa secretary of agriculture, said: "Given the spread of highly pathogenic avian influenza within dairy cattle in many other states, it is not a surprise that we would have a case given the size of our dairy industry in Iowa.

"While lactating dairy cattle appear to recover with supportive care, we know this destructive virus continues to be deadly for poultry."