Showing papers in "Theriogenology in 1985"

TL;DR: Hparin can prepare sperm for AR and fertilization in vitro and suggest that heparin-like material present in the female bovine reproductive tract may play a role in vivo in sperm capacitation and fertilizations.

TL;DR: A rapid staining procedure for examining nuclei of mammalian embryos is described and has proved to be an effective tool for studying the development of cow, hamster, mouse, pig, rabbit, and sheep embryos.

TL;DR: It may be beneficial to supply hormones to recipients and to transfer embryos at a particular stage of development at a precise interval after initiation of this treatment.

TL;DR: It is concluded that relationships between milk progesterone concentrations and ovarian responses to a superovulatory treatment exist and could be of interest in embryo transfer programs in when predicting the number of embryos to be recovered.

TL;DR: Embryo quality and stage of development were evaluated prior to freezing, immediately post-thaw and after 24 h culture in Ham's F10 with 5% FCS, and more embryos developed if frozen in straws compared to ampules, and plunging at -33 C resulted in higher quality embryos than plunged at -38 C.

TL;DR: The preovulatory follicle became the largest follicle in the ovary from which ovulation later occurred six or more days before ovulation in 65 of 79Preovulatory periods; the mean was day -7 (range, day -14 to day -4).

TL;DR: Embryonic vesicles that were lost during Days 11 to 15 usually disappeared without previous indications, except in three mares in which the vesicle was floating in a small collection of fluid, and the solid remnants and at least some of the fluids resulting from late embryonic and early fetal death were retained sometimes for weeks or months until the debris was apparently expelled through an open cervix.

TL;DR: Based on blood samples drawn at the time of PGF(2alpha) injection, progesterone concentration was significantly correlated with response rate but not with conception rate, and E had a significantly lower response rate and conception rate when compared with M and L.

TL;DR: It has been concluded that groups of macroscopically qualified follicles can be distinguished from each other by the steroid hormone concentration in the follicular fluid, and it is possible to predict the hormonal environment of the oocyte in any individual follicle of a defined size and quality.

TL;DR: Two distinct luteal morphologies were observed in the ovaries of mares studied by daily ultrasound examinations, and the hypothesis that the formation of a corpus hemorrhagicum is a necessary step in luteogenesis was not supported.

TL;DR: Ewes inseminated using laparoscopy did not conceive when their LH surge occurred >58 hr after progestagen withdrawal and the combined pregnancy rates and litter sizes were 67% and 2.21, respectively.

TL;DR: Splitting embryos was a worthwhile addition to the commercial ET programs and further trials are in progress to improve survival in vitro and pregnancy rates.

TL;DR: Results of this study indicate that one-cell ovine embryos can be successfully cultured through several cleavage divisions and glucose supplementation was beneficial for one- cell ovine embryo development.

TL;DR: Results indicated that the ultrasonic characteristics of the uterus may provide an instant indicator of estrogen exposure and may have practical value in judging the optimal time to breed.

TL;DR: Associations of percent live sperm, sperm number, sperm concentrations, sperm concentration, sperm motility, and potential breeding efficiency score with scrotal circumference were studied using data from the records of 465 Polled Hereford and 264 Simmental bulls.

TL;DR: Early embryonic death was studied in 354 pregnant mares during two breeding seasons and there was no difference (P>0.10) in the incidence of EED between mares inseminated with frozen-thawed and fresh semen.

TL;DR: Three factors were associated with lamb neonatal mortality: birthweight, number of lambs born per ewe and lamb sex; and lamb birthweight had the greatest predictive power for survival during the neonatal period.

TL;DR: Compared with reproductive efficiency obtained by natural mating and by artificial insemination (AI), not only following a natural estrus but also after an induced estrus with PGF2Alpha in Zebu cattle in the tropics, 244 adult cows were divided into 4 groups.

TL;DR: Optimal progesterone levels were identical to those for freshly collected embryos reported previously by Remsen et al. (1), and bovine corpus luteum quality graded by rectal palpation was related to some extent to progestersone levels but not to pregnancy rates.

TL;DR: Embryo recovery 6 days post-ovulation and pregnancy rate 50 days postestrus was similar for mares inseminated with spermatozoa extended in SM or NFDMS-glucose, and two fertility trials compared the use of SM and NFD MS- glucose extenders.

TL;DR: It is suggested that suckling inhibits the release of LH acyclic cows and that this is achieved primarily via a reduction in the number of pulsatile releases of LH.

TL;DR: The present study demonstrated that the hatched blastocyst is suitable for bisection in the goat.

TL;DR: Mean lamb birth weight, crown-rump length, number of functional uterine caruncles and caruncle weight and size did not vary significantly among breed groups or temperature chamber, and there was no indication that the high temperature imposed caused fetal dwarfing in lambs removed from the uterus at a standard age of seven days before expected parturition.

TL;DR: Embryo transfer and steroid hormone replacement therapy have been used to advantage in studies on prenatal mortality, particularly in sheep, but little is known of the manner in which the steroid hormones exert their effects on the environment of pre-implantation embryos; a stage when most mortality occurs.

TL;DR: Non-ovulatory ovarian follicles present during mid to late diestrus are necessary for luteal regression in non-pregnant cattle.

TL;DR: The embryonic loss seemed attributable to uterine-induced luteolysis in association with uterine inflammation, but the possibility of involvement of a primary luteal inadequacy or other factors in at least some of the mares was not eliminated.

TL;DR: Results indicated that equine follicular fluid contained a proteinaceous substance that suppressed circulating concentration of FSH and inhibited follicular growth and the delay in ovulation were attributed to the reduced concentrations of circulating FSH.