Abstract :
To evaluate the feasibility of long distance transport of ovine oocytes and in vitro produced
embryos. Santa Ines pluriparous sheep (n = 5) were synchronized with intravaginal
devices containing 0.3 mg progesterone (CIDR®, Pfizer, Netherlands) for 10 days. Thirty-six
hours prior to progesterone device removal and follicular aspiration, 0.04 mg d-cloprostenol
sodium (Ciosin®, Coopers, Brasil), 200 IU FSH (Folltropin®, Bioniche, Canada) and 300 IU
eCG (Novormon®, Syntex, Argentina) were administered intramuscularly. Oocyte retrieval
was performed via mid-ventral laparotomy, under general anesthesia. The oocytes were
evaluated and classified under a stereomicroscope and placed in cryovials with TCM 199,
aerated with 5% CO2, covered with mineral oil, sealed, wrapped with parafilm and stored
in a transport incubator at 38.5 ◦C. Oocytes were then transported via the road for 14 h to
the laboratory, where the oocytes then completed more than 10 h of IVM. In vitro fertilization
(IVF) was performed with frozen sperm from a single ram. On Day 3 the embryos
were placed in cryovials containing SOFovine (In Vitro Brasil, Sao Paulo, Brazil), aerated
with 5% CO2, covered with mineral oil, sealed, wrapped with parafilm and placed into the
same portable incubator. The embryos were returned to the farm under the same transport
conditions (km and h). Upon arrival at the farm, all embryos were evaluated and transferred
into recipient ewes 4 days after the initial oocyte retrieval. Embryos were transferred in sets
of 3 to 4, into the apex of the uterine horn, ipsilateral to the corpus luteum, by means of midventral
laparotomy, under general anesthesia. Pregnancy was diagnosed using transrectal
ultrasonography 30 days after embryo transfer. On average 9.8
±
5.7 oocytes (49 oocytes/5
donors) were obtained per donor, and 25 grade I morulae were transferred into 7 recipients.
One pregnancy (14.3%) was confirmed resulting in a healthy lamb. These results indicate
the feasibility of in vitro embryo production in sheep after maturation and embryonic
development following transport over long distances.
