New "Cloning" Research with an Interesting Twist Released
So with cloning (the type of which that is used for the equine is technically called "Somatic Cell Nuclear Transfer") an oocyte - any suitable oocyte - is taken and "enucleated", or has the nuclear DNA removed. Without getting too technical, the mtDNA from the oocyte remains, but doesn't (as far as we know) provide any characteristics related to the next generation, but is primarily associated with energy for the whole cell division (or fertilisation) process. The donor DNA is then placed within that enucleated oocyte and undergoes a process to convince the cell that it's just been fertilised. Cell division starts and in due course we hope, along comes a (DNA) replica of the DNA donor - except, in most cases, for the mtDNA. Because the mtDNA came from a completely different source (the oocyte that was used) than did the original donor's mtDNA (which would have come from his Dam's oocyte), if the clone's mtDNA is looked at, then it will be different from the DNA donor's mtDNA, so the differentiation can be made.
Where it gets tricky is if the "new" clone is male. If that stallion goes on to breed, there is no way to differentiate between an offspring of the original DNA donor, and an offspring of the clone, because the mtDNA would - in that offspring - have come from its Dam, not the (clone) Sire. This is the reason why we strongly encourage breed registries to record clones in some way so that there is not a "ringer" throw into the mix at some point - but that's another discussion for a different day...
So on to the twist...
A paper that is due to be published in the Theriogenology Journal (Choi Y., Ritthaler J., Hinrichs K. Production of a mitochondrial-DNA identical cloned foal using oocytes recovered from immature follicles of selected mares, Theriogenology, Article in press May 2014) reports on work that has been done where the oocytes that were used for the cloning process were taken from close female maternal line relatives - in one instance a cousin (a female offspring of a female sibling of the DNA donor's dam) and in another instance, a second cousin (a female offspring of a female offspring of a female sibling of the DNA donor's dam). As a consequence, the resulting foal (ultimately there was only one) had identical DNA - both nuclear and mtDNA - to the original DNA donor.
This has several interesting implications. Obviously the first is that it is now possible to replicate an animal that - at this time - we cannot differentiate genetically from the original; the second is that it opens the door to further research as to what effect - if any - the mtDNA truly does have on phenotype and performance in the equine.
Repetitive CEMO Shedding Situation in Ireland Declared "Resolved"The OIE have issued a follow-up report indicating that the stallion who last year tested positive and then negative (after treatment) for presence of Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), has undergone antibiotic therapy and lavage and has now repeatedly tested negative for presence of the pathogen. In June and July, five samples submitted to the Veterinary Research Laboratory (National laboratory) tested negative for the CEMO via polymerase chain reaction (PCR) testing and a sample in June tested at the Central Veterinary Research Laboratory (National laboratory) via pathogen isolation on cell culture also tested negative. As a consequence, the OIE have declared: "The non-thoroughbred stallion has been culture negative since June and has had several negative PCR tests. This outbreak is deemed to be resolved".
Irish CEM Situation Still OngoingThe OIE have published the following report concerning the Irish stallion that tested positive for the CEM organism last year, then cultured clean, and yet tested positive again this breeding season. It appears that some form of persistent or latent condition is present, or there is an issue with clearance methods in some way.
"The non-thoroughbred stallion still remains positive and officially restricted. Veterinary treatment consisted of antibiotic therapy and lavage and the stallion is currently culture negative but PCR positive. All other at risk animals were tested with all animals having negative results."
Noted Equine Reproduction Researcher Dr. Michelle LeBlanc DiesIt is with the deepest regret that we announce the death of noted researcher and veterinarian, Dr. Michelle LeBlanc. Dr. LeBlanc was noted for her interest and research into mare infertility, late pregnancy problems - with a particular interest in placentitis - and embryo transfer. With much of her research being used on a daily basis today by equine reproductive veterinarians world-wide, Dr. LeBlanc performed and published valuable research into the use and effect of oxytocin to assist pregnancy establishment and maintenance in mares with uterine clearance issues.
Dr. LeBlanc was for many years associated with the University of Florida, having been their Director of the Equine Research Program. More recently, Dr. LeBlanc had been working at Rood & Riddle Veterinary Hospital in Lexington, Kentucky, who last month renamed their equine reproduction center the "LeBlanc Reproduction Center". Among many honours received by Dr. LeBlanc, she was named 2000 Theriogenologist of the Year and received a Lifetime Achievement Award from the World Equine Veterinary Association in 2011.
Dr. LeBlanc, who died on Saturday of ovarian cancer, which she had been battling for several years, was 58. A fund has been established by the Theriogenology Foundation to honour LeBlanc's legacy. It is the organizers hope that the fund will become large enough to establish an endowment fund in order to honour her in perpetuity. Donations in LeBlanc's memory or honour can be sent to The Theriogenology Foundation, P.O. Box 3007, Montgomery, AL 36109, USA.
Are Clones Fertile? Well Yes They Are!Cloning history has been made with the birth of a foal in Texas. The as yet un-named filly shown at left was born April 10th and is by a clone of a World Champion Quarter Horse gelding "Go Wild" out of a clone of a 3 time World Champion Quarter Horse mare, "Spring Fling", who had been unable to produce a foal of her own. This is the first recorded instance of a foal being produced by a clone and out of a clone.
Equine-Reproduction.com To Present at CFERWe are pleased to announce that Equine-Reproduction.com's Jos Mottershead has been again invited to present at the Colloquium For Equine Reproduction being hosted by the British Society for Animal Science and being held at Nottingham University on 17th April.
The Colloquium is in its fourth season and combines an ability to present new scientific information to veterinarians, students and the public with an opportunity for veterinarians, researchers and breeders to meet and discuss ongoing issues and needs related to the subject. More details are available by following the linked image to the left.
Plaintiff in Failed Australian AI Case to Seek Leave to AppealLawyers for Australian Thoroughbred AI litigant, Bruce McHugh, have made application to lodge an appeal against the judgment. McHugh's lawsuit, an attempt to require the Australian Jockey Club to permit the use of artificial insemination (AI) in the breed failed just before Christmas. The request will be made before three Federal Court Judges and the decision should be handed down in short order.
Horse breeders worldwide will be interested to see if the Court will allow a review of the case, thereby possibly reopening the doors to end what many - both within and outside the Thoroughbred industry - perceive as an archaic restriction. Others will however consider this as a prospective new threat to the traditions of the industry.
CEM Reappears in County Galway, IrelandA stallion that had previously tested positive for the bacteria Taylorella equigenitalis, but had supposedly been successfully treated and cleared, has once again tested positive for the pathogen which is the causative agent of the notifiable sexually transmitted disease Contagious Equine Metritis. The report made to the OIE by Dr. Martin Blake, Chief Veterinary Officer for the Irish Department of Agriculture observes:
"The stallion in question is a non-thoroughbred. He was imported in 2009. He had negative CEM results in 2009, 2010 and 2011. He was positive for CEM in April 2012 but cultured negative on three occasions post treatment. He was tested in February 2013 pre the mating season and was positive on PCR. All horses on the premises are non-thoroughbreds and there is no indication that the disease has spread to other equines. Antibiotic extended semen has been used to inseminate all mares. We have a vast wealth of evidence from last year to show the effectiveness of the extender - circa. 80 mares were covered and no spread occurred. No mares have been inseminated in 2013".
RCVS Changes Format of Committees to Include Lay PersonsFollowing approval of a Legislative Reform Order (LRO) to the Veterinary Surgeon's Act, the UK's Royal College of Veterinary Surgeons (RCVS) will adjust its Preliminary Investigation and Disciplinary Committees to allow a limited number of lay people (non-Veterinarians) to become committee members.
Under the new legislation, the two statutory committees will move through a transition period until they completely comprise independently-appointed non-Council members, by July 2015.
The announcement, made at the end of January, indicates the following phases:
This move will provide regulation in line with modern practice, by ensuring that the same group of people is not responsible for setting the rules, investigating complaints and adjudication, and by bringing lay people formally into the Preliminary Investigation Committee.
The recruitment process is being handled by Thewlis Graham Associates and details can be found on their website.
The selection committee will comprise Sir Michael Buckley, Christopher Laurence MBE QVRM TD BVSc MRCVS and Dr Joan Martin MA FCOT. The closing deadline for applications is 5pm on Monday, 4 March 2013.
16/2/2013 - with thanks to the RCVS for information supplied.
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