The Pet Tree House - Where Pets Are Family Too : Smithsonian Institution Conservation Biology Institute The Pet Tree House - Where Pets Are Family Too : Smithsonian Institution Conservation Biology Institute
Showing posts with label Smithsonian Institution Conservation Biology Institute. Show all posts
Showing posts with label Smithsonian Institution Conservation Biology Institute. Show all posts

Friday, December 11, 2015

A Litter of Puppies Have Been Born Using In Vitro Fertilization


They're not only adorable - they're a scientific breakthrough. For the first time, a litter of puppies have been born using in vitro fertilization, say Cornell University researchers.

A female dog fertilized with 19 embryos gave birth to seven healthy puppies, according to a statement from Cornell's College of Veterinary Medicine. Two puppies are from a beagle mother and a cocker spaniel father, and the other five are the offspring of two pairs of beagle fathers and mothers.

"IVF was first done in people back in the mid 1970s," Alex Travis, associate professor of reproductive biology at the Baker Institute for Animal Health, told CBS News. Yet until now, scientists hadn't been able to perform it successfully in dogs, despite many years of trying, he said.

For in vitro fertilization, a mature egg is fertilized in the lab with a sperm, and an embryo is produced. The embryo is then transferred into a host female at the right time in her reproductive cycle.

The first challenge for the researchers was to collect mature eggs from the female oviduct (called Fallopian tubes in humans). The researchers first tried to use eggs that were in the same stage of cell maturation as other animals, but since dogs' reproductive cycles differ from other mammals, those eggs failed to fertilize.

It's not as easy to perform in vitro fertilization in dogs as it in in people, or cats, Penn Vet's Dr. Margaret Casal told CBS News. "The cycle in the dog is so very different than in other species."


"Dogs only cycle twice a year so if your'e doing experiments, there's not a lot of material," said Travis.

Through experimentation, the Cornell researchers discovered that if they left the egg in the oviduct one more day, the eggs reached a stage where fertilization was greatly improved.

Also, by adding magnesium to cell culture cultures, Travis said they were able to better prepare the sperm for fertilization.

"We made those two changes, and now we achieve success in fertilization rates at 80 to 90 percent," Travis explained in a statement.

The final challenge for the researchers was freezing the embryos. Freezing them allowed the researchers to wait until the right time in the female dog's reproductive cycle and then insert them into the oviducts. Travis said that part of the process was performed in May 2015.

In dogs, pregnancy is 63 days from ovulation -- a little over 2 months, Travis said.

The Cornell team previously delivered Klondike, the first puppy born from a frozen embryo in the Western Hemisphere, in 2013.

This first litter of IVF puppies, born July 10th, has broad implications for wildlife conservation, Travis told CBS News.

"We can freeze and bank sperm, and use it for artificial insemination." He said the technique could be used to conserve the genetics of endangered species.

"The reason for doing things like this is that it will lead to the preservation of species that are almost lost. Canid types - wolves, foxes - certain sub-species. There are many different types. They may not be facing extinction just yet but some are running into a crisis," said Penn Vet's Casal, an associate professor of medical genetics, reproduction and pediatrics for dogs and cats.

She said some types of wolves, for example, are very genetically similar animal to animal - they have very similar immune systems.

"If some virus comes along that has mutated, it can essentially wipe out the population. This gives the ability to freeze embryos and perform IVF later to revive a species that may have been brought to extinction," Casal said.

With new gene editing techniques, researchers may one day be able to remove genetic diseases and traits in an embryo, too, ridding dogs of heritable diseases.

"With a combination of gene editing techniques and IVF, we can potentially prevent genetic disease before it starts," Travis said.

Canines share more than 350 similar heritable disorders and traits with humans, almost twice the number as any other species. So, dogs now may offer a "powerful tool for understanding the genetic basis of diseases," Travis said.

"Yes this is a very big deal. It's pretty spectacular to get that to work," said Casal.

Jennifer Nagashima, a graduate student in Travis' lab and the first to enroll in the Joint Graduate Training Program between the Smithsonian Conservation Biology Institute and Cornell's Atkinson Center for a Sustainable Future, is the paper's first author. The research was described in a study published today in the scientific journal PLOS ONE.

Travis said the puppies have all gone to happy homes, including his own. "I have two of them. We named them after colors and I have Red and Green." The puppies turn five months old this week.

IVF puppy
These adorable pups are the first litter of puppies born by in vitro fertilization. Cornell University researchers introduced them to the world on Dec. 9, 2015. The seven puppies were conceived using an IVF technique that took years to develop successfully for dogs, whose reproductive cycles are much different than humans'.




Cuddle time
To create the IVF puppies, a female dog was fertilized with 19 embryos. She gave birth to seven healthy puppies, according to Cornell's College of Veterinary Medicine. Two of the puppies are from a beagle mother and a cocker spaniel father, and the other five are the offspring of two pairs of beagle fathers and mothers.




Look-alikes
Two of the seven puppies born by in vitro fertilization. Cornell researchers say the technique used to create this litter of pups could also help conserve endangered species and eradicate heritable diseases in dogs.




Frolicking in the sun
These frisky puppies were born using in vitro fertilization, the first successful IVF litter of dogs.




Chew toy time
Two of the IVF puppies play with their chew toys.




A little TLC
One of the IVF puppies gets some love from the team at Cornell.




Out for a stroll
One of the seven healthy puppies born in the first litter using in vitro fertilization.




Faces to love
The first litter of puppies born by in vitro fertilization. Cornell University researchers say the successful use of IVF in animals could eventually also help with conserving endangered species and eradicating heritable diseases in dogs.




Sniffing around
Two of the first IVF puppies, born with the help of Cornell University researchers after decades of failed efforts.






Puppy love
The first litter of puppies born by in vitro fertilization. Researchers at Cornell's College of Veterinary Medicine transferred 19 embryos to the mother dog, who went on to give birth to seven healthy puppies. Two puppies are from a beagle mother and a cocker spaniel father, and the other five are the offspring of two pairs of beagle fathers and mothers.





IVF puppies
It's not as easy to perform in vitro fertilization in dogs as it in in people, or cats, Penn Vet's Dr. Margaret Casal told CBS News. "The cycle in the dog is so very different than in other species."






VF puppies
Cornell University researchers introduced the first litter of puppies born by in vitro fertilization on Dec. 9, 2015. Researchers had been trying since the 1970s to develop an IVF process that worked in canines, whose reproductive cycles are much different than humans'.


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In Vitro Fertilization is No Longer a Treatment Reserved for Making Small Humans Can Now be Used to Produce Puppies


It's official: In vitro fertilization is no longer a treatment reserved for making small humans. The assisted reproduction technique that has led to the birth of more than 5 million human babies around the world can now be used to produce puppies.

In work expected to further efforts to preserve endangered wildlife and enhance human health, scientists at Cornell University have succeeded in joining canine egg and sperm, creating embryos, implanting them in the uterus of a female carrier and seeing the gestation of those puppies-to-be to birth.

The successful birth of seven healthy puppies ended about two decades of failed efforts to make the commonly used infertility treatment work on canines, whose reproductive biology differs from that of humans in a wide range of particulars. In humans, physicians have made a science -- and a booming business -- of stimulating egg growth, retrieving oocytes, introducing egg and sperm, cultivating the resulting proto-embryos in laboratory medium and transferring blastocysts to a woman's uterus.

But that multi-step process needed to be tweaked at many points for success to be achieved in dogs. Success was achieved after 19 embryos were transferred into a healthy host female beagle and, after a period of about 63 days, seven healthy pups were delivered by Caesarian section.

Report of the new research was published Wednesday in the journal PLoS One.

Pierre Comizzoli, a research veterinarian at the Smithsonian Institution's Conservation Biology Institute, said the work will offer vital insights into the varied reproductive biologies of many animals. There are 5,500 mammalian species, but scientists have only characterized in detail the biologies of about 100 of them.

For conservation biologists intent on bringing a wide range of endangered mammalian species back from the brink, the project should offer new perspectives on techniques that work, said Comizzoli, who is not among the authors but has been the Smithsonian's point person for joint work with Cornell on the topic.

For human health too, the new work may bring discoveries. Domestic dogs share with humans many diseases, including cancers, diabetes and genetic disorders. So their response to experimental treatments can offer useful insights into the likely outcomes of those treatments in humans.

At the cusp of a new era in which disease-related genes might be edited out of a human's genome, dogs already have provided an important model for experimentation. Because gene editing is done in the laboratory, only with the success of IVF in canines can the animals become a useful test bed for editing changes that might -- pending much ethical and scientific debate -- be used in humans.



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