Uterine and Corpus Luteum Blood Flow Evaluation Prior to Uterine Flushing in Llama Embryo Donors.

The aim of this study was to assess the uterine blood flow (UBF) and corpus luteum blood flow (CLBF) in llamas 8 days post-mating, using color-Doppler ultrasonography (CDU), to determine the possible relationship between vascularization and the presence of an embryo. Adult females ( = 25) were used to monitor ovarian dynamics by palpation and transrectal ultrasonography until detection of a ≥6 mm growing follicle. Females were randomly assigned to one of two groups: Group I ( = 19), were mated and ovulation was induced by a single dose of buserelin (GnRH analog) that same day (Day 0); and Group II ( = 6), only ovulation was induced (control).

Development of a GnRH-PGF Based Synchronization and Superstimulation Protocol for Fixed-Time Mating in Llama Embryo Donors.

The aim of the present study was to evaluate the application of a GnRH-PGF based synchronization and superstimulation protocol for fixed-time natural mating in llama embryo donors. All females ( = 8) received 8 μg IM of GnRH analog (GnRHa; buserelin) on day 0, regardless of follicular status. After eight days, another GnRHa dose was administered followed by 250 μg IM PGF (cloprostenol).

Administration of progesterone BioRelease LA inhibits follicular growth in llamas (Lama glama) regardless of follicle diameter at the start of treatment.

The aims of the study were twofold: first, the comparison of the pharmacokinetics parameters of two doses of Progesterone BioRelease LA, (BioRelease Technologies, Lexington, KY, USA) one of 300 mg and other of 150 mg and their effects on ovarian dynamics in llamas. Based on the results from the first study, the aim of the second study was to evaluate the effect of the doses of 150 mg of progesterone on follicular activity considering the stage of the largest follicle at the beginning of treatment. The results in Study 1 showed that both doses of the formulation induced plasma progesterone concentrations higher than 1 ng/ml during the first 6 days of treatment in all females, progesterone concentrations steadily decline until Day 5 following by a slowly decrease.

Production, Preservation, and Transfer of South American Camelid Embryos.

The current review summarizes progress in the field of and production of South American Camelid embryos. Both methods require ovarian superstimulation (with FSH and eCG) to obtain multiple ovulations ( embryo production) or to induce follicle growth for oocyte collection ( embryo production). Moreover, superstimulation entails prior administration of hormones that inhibit follicular growth (progesterone, progestagens, and estrogens).

In vitro production of llama (Lama glama) embryos by IVF and ICSI with fresh semen.

The interest for South American camelids has increased in the last years. The aim of the present research was to compare the in vitro production of Lama glama embryos using two techniques: in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). For IVF technique, we compared the effect of adding or not, heparin, penicillamine and hypotaurine as sperm capacitating agents.