Tag Archives: #canine

Re­search­ers Identify A Gene That Causes Can­ine Hered­it­ary Deaf­ness in Pup­pies (Medicine / Veterinary)

Finnish researchers have been the first to determine the cause for the nonsyndromic early-onset hereditary canine hearing loss in Rottweilers. The gene defect was identified in a gene relevant to the sense of hearing. The study can also promote the understanding of mechanisms of hearing loss in human.

Hearing loss is the most common sensory impairment and a complex problem in humans, with varying causes, severity and age of onset. Deafness and hearing loss are fairly common also in dogs, but gene variants underlying the hereditary form of the disorder are so far poorly known.

Researchers from the University of Helsinki and the Folkhälsan Research Center focused on a rare type of hearing loss observed in Rottweilers. It begins early in puppyhood and progresses to deafness at the age of few months. A similar type of hearing loss was also seen in a small number of mixed-breed dogs, of which the majority had Rottweiler ancestry.

“We identified the variant in the LOXHD1 gene, which plays a key role in the function of the cilia of the cochlear sensory cells. While the exact mechanism of deafness is not known, variants of the same gene cause hereditary hearing loss in humans and mice as well,” says Docent Marjo Hytönen from the University of Helsinki and the Folkhälsan Research Center.

Hearing impairment caused by the LOXHD1 gene defect is a recessively inherited trait, which means that to develop the disorder, the dog must have two copies of the defective gene, one from the father and one from the dam.

“Through our collaboration partner, we had the chance to investigate the prevalence and breed specificity of the gene variant in a unique global dataset of some 800,000 dogs. No surveys of similar scope have previously been published,” says Professor Hannes Lohi from the University of Helsinki and the Folkhälsan Research Center.

New individual dogs that had inherited the gene defect and were also found to be deaf were identified in the screening.

“This enhances the significance of our finding. Thanks to our gene discovery, dogs used for breeding can now be tested for the defect. This makes it possible to avoid combinations that could result in puppies who will lose their hearing.”

The recent study is part of a research programme (https://www.koirangeenit.fi/english/) led by Professor Lohi and investigating the genetic background of hereditary diseases. Currently ongoing are several projects whose goals include the determination of genetic causes for hearing loss.

According to Marjo Hytönen, the preliminary results are promising.

“We have observed that both previously unknown hereditary congenital hearing loss and adult-onset hearing loss occur in several dog breeds. In addition to dogs, the preliminary findings open new avenues for investigating human hereditary hearing defects.”

Featured image credit: Mostphotos

Ori­ginal art­icle: 

Marjo K Hytönen, Julia E Niskanen, Meharji Arumilli, Casey A Knox, Jonas Donner, Hannes Lohi. Missense Variant in LOXHD1 is Associated With Canine Nonsyndromic Hearing Loss. Human Genetics. DOI https://doi.org/10.1007/s00439-021-02286-z

Provided by University of Helsinki

Mystery Canine Illness Identified (Medicine)

An outbreak of vomiting among dogs has been traced back to a type of animal coronavirus by researchers.

Vets across the country began reporting cases of acute onset prolific vomiting in 2019/20.

The Small Animal Veterinary Surveillance Network (SAVSNet) at the University of Liverpool asked vets for help in collecting data, with 1,258 case questionnaires from vets and owners plus 95 clinical samples from 71 animals.

Based on this data, a team from the universities of Liverpool, Lancaster, Manchester and Bristol identified the outbreak as most likely to be a variant of canine enteric coronavirus (CeCoV).

Canine coronavirus only affects dogs and is not the same as Sars Cov2 which causes Covid in humans. Researchers found no evidence of any similar illness in people.

The work is published in Emerging Infectious Diseases.

The team are working on a project funded by the Dogs Trust called SAVSNet-Agile which aims to develop a national surveillance system for canine health.

Dr Barry Rowlingson from Lancaster University said: “We’ve developed complex statistical models to look for disease outbreaks. Being able to rapidly detect increased incidence, without triggering a false alarm from a natural random variation, is the key problem here. Early detection is crucial to early treatment and enhanced monitoring.

“The SAVSNet Agile project aims to feed information back to local veterinary practices so they can be alert to any new outbreaks.”

Vets began to suspect an infectious cause because vomiting was more frequent than is typical for canine gastroenteritis.

SAVSNet researchers found a specific and significant increase in the number of dogs recorded as exhibiting gastroenteric signs between late December 2019 and March 2020.

As well as reusing health records, SAVSNet also collected questionnaire data from vets and owners caring for affected animals, as well as healthy controls. This showed male dogs were more at risk than females.

Charlotte Appleton, SAVSNet Agile PhD Student, said: “Obtaining such important results at an early stage of my PhD is a wonderful achievement and will hopefully provide a pathway of higher visibility into the health of domestic animals.”

Featured image: Vets were asked for help in collecting data. © Lancaster University

Reference: Radford AD, Singleton DA, Jewell C, Appleton C, Rowlingson B, Hale AC, et al. Outbreak of Severe Vomiting in Dogs Associated with a Canine Enteric Coronavirus, United Kingdom. Emerg Infect Dis. 2021;27(2):517-528. https://dx.doi.org/10.3201/eid2702.202452

Provided by Lancaster University

Sabretooths Evolved Different Hunting Styles Over 250 Million Years (Paleontology)

Sabre-toothed predators evolved an unknown diversity in hunting and killing styles over the last 250 million years, a new study reveals.

Skulls and life reconstructions of the six different sabre-tooth species used in the study (Stephan Lautenschlager, University of Birmingham).

Sabretooth cats are among the most iconic fossils, but sabre-toothed animals came in all shapes and sizes and nearly a hundred different species are known to science so far. Not all them belonged to the same family as modern cats and some of them even predate dinosaurs.

Elongated canine teeth, reaching a length of up to 30 cm in some species, evolved independently in seven different evolutionary lines of carnivorous animals. Due to similar skull and tooth shape, it had long been assumed that all of these animals hunted and killed prey in the same manner. This assumption has now been refuted by a new study, published today in Proceedings of the Royal Society B.

An international team of scientists from the UK, Spain and Germany examined over 60 different sabretooth species. Using computer simulations, the team investigated the functional capabilities of the teeth and skulls, such as calculating bite forces and bending strength.

Computer simulation results for three fossil sabretooth species compared to a modern lion showing maximum jaw gape and stress distribution in the lower jaw. Picture Credit: Stephan Lautenschlager, University of Birmingham

Dr Stephan Lautenschlager, lead author and Lecturer for Palaeobiology at the University of Birmingham, commented: “It is fascinating to see that so many different species have evolved elongated canine teeth to subdue prey, but our results show that they used these sabre-like teeth differently to do so.

The study revealed that sabre-toothed animals may have looked very similar, but they used their teeth in different ways. Some species had specialised on hunting small prey using the canine teeth to inflict deep wounds. Other species were likely pack hunters specialising on large prey with reinforced bone structures to stabilise the jaws.

Dr Lautenschlager added: “We know that different sabre-tooth species shared the same ecosystem. Using computational methods, we can show that their specialisation on different prey allowed them co-exist and to avoid competition.”

References: Stephan Lautenschlager , Borja Figueirido , Daniel D. Cashmore , Eva-Maria Bendel and Thomas L. Stubbs, “Morphological convergence obscures functional diversity in sabre-toothed carnivores”, Proceedings Of The Royal Society B, 2020 doi: https://doi.org/10.1098/rspb.2020.1818 link: https://royalsocietypublishing.org/doi/abs/10.1098/rspb.2020.1818

Provided by University Of Birmingham