Quality and Developmental Ability of Dromedary (Camelus dromedarius) Embryos Obtained by IVM/IVF, In Vivo Matured/IVF or In Vivo Matured/Fertilized Oocytes

Abstract

The effect of source of cumulus-oocytes-complexes (COCs), maturation and fertilization conditions on developmental competence of dromedary embryos was examined. Thirty-six adult females were superovulated with equine Chorionic Gonadotropin (eCG) injection (3500 IU, IM) and divided in three groups of 12 females each. Group 1 provided 138 COC's collected from follicles >or= 5 mm 10 days after stimulation prior hCG treatment and matured in vitro for 30 h. Group 2 provided 120 in vivo matured oocytes which were aspirated from their follicles 20 h after hCG (3000 IU, IV) given on day 10 follow eCG injection. Group 3 provided 65 in vivo matured/fertilized oocytes. Females in Group 3 received hCG on day 10 following eCG treatment and then were mated 24 h later. Fertilized oocytes were collected from the oviducts of females 48-h post-mating. Quality of the oocytes was assessed after in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) of COCs. All cultures were performed in three replicates (n = 3) at 38.5 degrees C, under 5% CO(2) and high humidity (>95%). Only COCs with cumulus and homogenous (dark) cytoplasm were used. Nuclear maturation rate for Groups 1 and 2 was determined by epifluorescence microscopy in a sample of COCs (n = 30) denuded, fixed and stained with Hoechst 33342. To study the viability of obtained embryos, hatched blastocysts from each group were transferred to recipients followed by pregnancy diagnosis using ultrasonography at 15, 60 and 90 days. The percentage of COCs reaching metaphase II (MII) after 30 h of maturation was slightly but not significantly higher for in vivo matured oocytes (28/30; 93%) than those in vitro matured (25/30; 84%). The total rate of cleavage (2 cells to blastocyst stage) was not different for the three groups. However, significantly (p < 0.05) more blastocyst and hatched blastocysts were obtained from in vivo matured and in vivo fertilized oocytes (Group 3; 52% and 73%) than from in vitro fertilized oocytes whether they were matured in vitro (Group 1; 35% and 32%) or in vivo (Group 2; 32% and 45%). Pregnancy rates were not significantly different amongst all groups for the three first months following embryo transfer. All pregnancies were lost after day 90 follow transfer except for in vivo matured and in vivo matured/fertilized groups. Only in vivo matured/in vitro fertilized and in vivo matured/fertilized produced embryos continued normal development until term and resulted in the birth of normal and healthy live calves. Six claves (29%; 6/21) were born from Group 3 and one (8%; 1/13) calf was born from Group 2. This study shows that the IVC system used is able to support camel embryo development. However, developmental competence and viability of dromedary embryos may be directly related to the intrinsic quality (cytoplasmic maturation) of oocytes.

Developmental competence of Dromedary camel (Camelus dromedarius) oocytes selected using brilliant cresyl blue staining

“…Eighteen hours post insemination, presumptive zygotes were washed and cultured in modified KSOMaa (Khatir et al ., 2007), 5 zygotes/50 µl drop under mineral oil at 39°C in 5% CO 2 humidified air atmosphere until day 7 (day 0 = day of insemination). The number of cleaved embryos (2–8 cells) was determined at 48 hpi.…”

A systemic review on ultrasonographic applications in camels

“…Moreover, several foetal parameters including orbital diameter, biparietal diameter, abdominal diameter, chest depth and ruminal diameter are measured by ultrasound. Also, ultrasonography is used during the embryo transfer programmes (Skidmore and Billah, 2005;Anouassi, 2006 andBillah, 2011), interspecies embryo transfer (Niasari-Naslaji et al, 2009), assessment of somatic cell nuclear transfer Anouassi, 2008 andKhatir et al, 2009) and assessment of the quality and developmental ability of dromedary embryos obtained by IVM/IVF, in vivo matured/IVF or in vivo matured/fertilised oocytes (Khatir et al, 2007). Moreover, ultrasonography is a beneficial tool for comparison of pregnancy rates in dromedary camels after deep intra-uterine versus cervical insemination (Skidmore and Billah, 2006).…”

Production of blastocysts following in vitro maturation and fertilization of dromedary camel oocytes vitrified at the germinal vesicle stage

“…Eighteen hours post-insemination (pi), presumptive zygotes were washed three times in H-TCM 199 supplemented with 5% FCS and then twice in embryo culture medium (modified KSOMaa [ 35 , 39 ]) and cultured in groups of five zygotes per 50 μL drops of embryo culture medium under mineral oil at 39 °C in a humidified atmosphere of 5% CO 2 , 5% O 2 , and 90% N 2 until Day 7 (Day 0 = day of insemination). Cleavage, morula and blastocyst development were recorded on Days 2, 4 and 7 pi, respectively.…”