During this time, the cow’s udder begins to swell as it prepares for milk production. The pre-calving stage occurs in the last few weeks of pregnancy. The mother’s body adjusts to support the growing fetus by providing the necessary nutrients and hormones. The fetal development stage lasts for approximately seven months.ĭuring this period, the fetus undergoes significant growth and development, including the formation of organs, bones, and muscles. Once the embryo is implanted, it starts to develop into a fetus. During this stage, the embryo develops rapidly, and the placenta begins to form. This process, known as implantation, occurs within the first week after fertilization. Early Embryonic DevelopmentĪfter successful mating or artificial insemination, the fertilized egg travels to the cow’s uterus and implants itself into the uterine wall. The Safari Park says the work may be applicable for other rhino species, including the critically endangered Sumatran and Javan rhinos.Similar to humans and other mammals, cow pregnancy can be divided into three main stages: early embryonic development, fetal development, and pre-calving. The study, which has yet to be published, can be found at j.mp/rhinostem. So the cells created have a healthier genetic profile. Unlike earlier methods, it doesn’t use viruses to deliver genes that help convert the cells. Loring and Ryder are co-authors of a recent study describing how stem cells were produced from four northern white rhinos with a method they say is superior. This is what will be implanted into the southern white rhino surrogate mothers.
These will be united by in vitro fertilization to create an embryo. Thawed cryopreserved tissue will be converted into the artificial embryonic stem cells, then matured into egg and sperm cells. The rhino project is even more complicated. They will be matured into brain cells of the type destroyed in Parkinson’s, then implanted into the patient’s brains. These induced pluripotent stem cells, as they are called, are to be created from the patients themselves. Loring is leading a separate project to use the cells to treat Parkinson’s disease. He shared a Nobel Prize in 2012 for his discovery. Japanese scientist Shinya Yamanaka demonstrated that adult mammalian cells can be turned into artificial embryonic stem cells. The technology to put these cells to use finally arrived in 2007. He established a cryobanked collection of tissue from these animals, known as the “Frozen Zoo.” Ryder suggested deep-freezing tissue from endangered animals, in the hope that future technology could recreate whole animals from these cells. The project’s roots go back decades to a dream inspired by Oliver Ryder, a geneticist at San Diego Zoo Global, the zoo’s conservation arm. So the zoo and allied researchers like Loring have had to invent the technology as they go along. Much of the rhino reproductive system hasn’t been studied before, she said. “That’s awesome,” Loring said from Germany.
Jeanne Loring, a stem cell scientist at The Scripps Research Institute, has worked on this project with the zoo for years. Victoria and five other female southern white rhinos at the Safari Park’s Nikita Khan Rhino Rescue Center have been conditioned for years to willingly accept the most intimate handling, such as ultrasound examination of their reproductive tracts.
Another white rhino, Nola, died in November 2015 at the Safari Park. The last male, Sudan, died in March in a Kenya preserve. Only two northern white rhinos are alive today, both females. More dead whales found in San Francisco Bay Area.Rare California frogs breeding in the Santa Monica Mountains.Ventura nonprofit Paso Pacifico takes on poachers with decoy sea turtle egg.A failure would mean more work needs to be done, or that the female is infertile. The lengthy rhino gestation period means the baby isn’t due until the summer of 2019. The pregnancy is a dress rehearsal for the ultimate goal of creating more northern white rhinos, grown from embryos made from stem cells. The developing baby is also a southern white rhino, conceived on March 22 through artificial insemination. It’s an event of vital importance for a program to bring back her nearly extinct kin, the northern white rhino. SAN DIEGO - Victoria, a southern white rhino at the San Diego Zoo Safari Park, is pregnant. Watch Video: Hopes for white rhino grow with zoo pregnancy
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