RESUMEN
Advanced reproductive technologies are being applied for the propagation of squirrel monkeys, to ensure their preservation as a genetic resource and the effective use of their gametes in the future. In the present study, oocytes and spermatozoa were collected from live squirrel monkeys, following which piezo intracytoplasmic sperm injection (ICSI) was performed using these gametes. Follicular development was induced by administering equine chorionic gonadotropin (eCG) containing inhibin antiserum to an immature squirrel monkey female. The unilateral ovary was excised after the administration of human chorionic gonadotropin (hCG), to induce ovulation, following which the larger developed follicular oocytes were collected. Follicular oocytes were prepared for ICSI using sperm from the epididymal tail of a unilateral testis extracted from a mature male. The embryos were continuously incubated in CMRL 1066 medium supplemented with 10% (v/v) fetal bovine serum. Embryo culture was performed with cumulus cells. Two experiments of ICSI carried out with three females resulted in 14 mature oocytes from the 49 cumulus-oocyte complexes collected and five embryos, three of which developed into blastocysts. These blastocysts were vitrified, thawed, and transferred to recipient monkeys, but no pregnancies resulted. In conclusion, the present study is the first to successfully produce ICSI-derived blastocysts from MII oocytes obtained by means of hormone administration (a combination of eCG+inhibin antiserum and hCG) and in vitro maturation in immature squirrel monkeys.
Asunto(s)
Blastocisto/fisiología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Recuperación del Oocito/veterinaria , Saimiri/embriología , Inyecciones de Esperma Intracitoplasmáticas/veterinaria , Animales , Criopreservación/veterinaria , Técnicas de Cultivo de Embriones/métodos , Técnicas de Cultivo de Embriones/veterinaria , Transferencia de Embrión/veterinaria , Especies en Peligro de Extinción , Femenino , Masculino , Recuperación del Oocito/métodos , Embarazo , Resultado del Embarazo , Inyecciones de Esperma Intracitoplasmáticas/métodosRESUMEN
This study evaluated manual caliper measurement of fetal BPD in Saimiri through the abdomen of the dam (TBPD) for correlation with paired ultrasound measurements, prediction of delivery date, subspecies variation, prediction of pregnancy outcome, and correlation between postpartum BPD and TBPD. Regression analysis revealed a close relationship between TBPD measurements and those obtained by ultrasound (P < 0.001). TBPD for Saimiri boliviensis boliviensis increased from a mean of 14.8 +/- 0.3 mm for 11 weeks prepartum to a delivery week measurement of 33.2 +/- 0.2mm. Delivery-week TBPD of Saimiri boliviensis peruviensis were significantly smaller than Saimiri sciureus sciureus (P < .05). Delivery week TBPD had a correlation coefficient of 0.64 with paired post-patrum measurements. No complications were associated with the technique. Delivery date could be predicted within two weeks. TBPD is an inexpensive, safe, rapid method of approximating fetal growth during the last half of pregnancy in Saimiri.
Asunto(s)
Desarrollo Embrionario y Fetal , Edad Gestacional , Saimiri/embriología , Animales , Antropometría , Femenino , Hueso Parietal/crecimiento & desarrollo , Embarazo , Análisis de RegresiónRESUMEN
The monkey's foveola normally contains significant numbers of retinal ganglion cells. The somata of foveola cells are larger than those of other cells in the central retina. Their dendritic fields are up to 50 times larger in area than those of nearby cells in the foveal slope. Experimentally induced reductions in the number of ganglion cells in central retina results in alterations in the size and distribution of cells within the foveola. In these animals the foveola is abnormally small and contains an abnormally large number of cells having smaller than normal cell bodies and dendritic fields. These studies indicate that the formation of the foveola as well as the development of the morphology of cells within the foveola and foveal slope depend during development on high densities of retinal ganglion cells within the central retina.
Asunto(s)
Fóvea Central/embriología , Células Ganglionares de la Retina/fisiología , Animales , Recuento de Células , Fóvea Central/citología , Fóvea Central/crecimiento & desarrollo , Macaca fascicularis/embriología , Morfogénesis , Saimiri/embriologíaRESUMEN
In order to obtain timed pregnancies in squirrel monkeys and to monitor development of the size of the fetus and its brain, tests were made of various combinations of vaginal examination, bioassay of chorionic gonadotropin (CG), measurement of maternal body weight and uterine fundus height during pregnancy, and determination of fetal biparietal diameter by ultrasonography and magnetic resonance imaging. The usefulness of these methods in developmental and teratological studies is discussed.
Asunto(s)
Encéfalo/embriología , Desarrollo Embrionario y Fetal , Preñez/fisiología , Saimiri , Animales , Peso Corporal , Gonadotropina Coriónica/orina , Femenino , Imagen por Resonancia Magnética , Embarazo , Saimiri/embriología , Ultrasonografía Prenatal/veterinaria , Útero/anatomía & histología , Útero/fisiologíaRESUMEN
The physical growth and brain development of the captive bred male and female squirrel monkeys have shown that the male grows at a significantly faster rate with respect to these parameters in the postnatal life, starting from preweaning stage as compared to the female infant. During the prenatal life the male and the female fetuses grow at similar rates and show comparable brain development as indicated by its weight.
Asunto(s)
Encéfalo/crecimiento & desarrollo , Haplorrinos/crecimiento & desarrollo , Saimiri/crecimiento & desarrollo , Animales , Animales de Laboratorio/crecimiento & desarrollo , Encéfalo/anatomía & histología , Encéfalo/embriología , Tamaño de los Órganos , Saimiri/embriologíaRESUMEN
An in vitro fertilization system was developed for the squirrel monkey. Oocytes recovered from follicles of gonadotropin-treated females and cultured in vitro with spermatozoa resulted in fertilized ova capable of developing to the four-cell stage in culture. In total, 264 follicular oocytes were recovered from 922 follicles in 38 Saimiri sciureus. Seventy-nine developed to the first polar body stage, and 32 of the 79 were fertilized in vitro.