La crianza de camélidos domésticos, alpacas y llamas, es una de las actividades de mayor importancia e impacto en el desarrollo socioeconómico de la población altoandina del Perú, debido a su capacidad de adaptación a condiciones ambientales difíciles, por encima de los 4,000 msnm, y a su utilización como fuente de proteína de origen animal y de transporte y en el caso de la alpaca, para la producción de fibra de buena calidad. El Perú cuenta con más de 3 millones de alpacas (87% de la población mundial) y la segunda población mundial de llamas (+1 millón); sin embargo, las deficiencias en los esquemas tradicionales de crianza, como la crianza conjunta de alpacas y llamas, con los consecuentes cruces no programados, han contribuido a reducir la calidad genética de los animales, ocasionando una pérdida en la cantidad y calidad de fibra, reportándose que el 45% de la prod...

The present study was conducted to evaluate the effect of different fractions of llama seminal plasma, based on the molecular weight (MW), on the ovulation. Fifty four female adult llamas without calf at foot and in good reproductive conditions were used. The animals were bearing a >7 mm dominant follicle determined by ultrasound diagnosis during a three consecutive days. Females were randomly distributed in six groups: A, fraction of seminal plasma with MW >30 kDa; B, fraction of seminal plasma with MW >10 and <30 kDa; C, fraction of seminal plasma with MW >5 and <10 kDa ; D, fraction of seminal plasma with MW <5 kDa; E, complete plasma seminal; and F, PBS. Animals were treated with a 1.5 ml solution of the corresponding fraction or placebo via i.m. Ovarian ultrasound was performed at day 2 and 9 post-treatment to determine the ovulation rate and the size of the cor...

The present study was carried out to evaluate the effect of deposition site of seminal plasma on the ovulation rate and size of corpus luteum in alpacas. Non-lactating females bearing a ≥7 mm follicle detected by ultrasound were selected (n = 91). Follicular wave was synchronized by injecting 5 mg of LH and then, the presence of a dominant follicle ≥7 mm was determined 12 days later through ultrasound evaluation. Alpacas were assigned to one of six experimental groups: G1 (n=16) seminal plasma (SP) by intramuscular injection – i.m.; G2 (n=15) phosphate-buffered saline (PBS) i.m.; G3 (n=16) SP by intrauterine administration – i.u.; G4 (n=15) PBS i.u.; G5 (n=15) SP i.u. with curettage; G6 (14) PBS by i.u. with curettage. Ovulation rate and corpus luteum were determined by ultrasound evaluation on D2 and D8 (D0 = day of treatment). Serum samples were taken from the jugular vein on D...

The present study was carried out to evaluate the effect of deposition site of seminal plasma on the ovulation rate and size of corpus luteum in alpacas. Non-lactating females bearing a ≥7 mm follicle detected by ultrasound were selected (n = 91). Follicular wave was synchronized by injecting 5 mg of LH and then, the presence of a dominant follicle ≥7 mm was determined 12 days later through ultrasound evaluation. Alpacas were assigned to one of six experimental groups: G1 (n=16) seminal plasma (SP) by intramuscular injection – i.m.; G2 (n=15) phosphate-buffered saline (PBS) i.m.; G3 (n=16) SP by intrauterine administration – i.u.; G4 (n=15) PBS i.u.; G5 (n=15) SP i.u. with curettage; G6 (14) PBS by i.u. with curettage. Ovulation rate and corpus luteum were determined by ultrasound evaluation on D2 and D8 (D0 = day of treatment). Serum samples were taken from the jugular vein on D...

El presente estudio fue realizado con el propósito de evaluar el efecto de varias fracciones de plasma seminal de llamas, según su peso molecular (PM), sobre la inducción de la ovulación. Se utilizó 54 llamas hembras sin cría y en óptimo estado reproductivo, con folículo dominante >7 mm de diámetro determinado por ecografía transrectal por tres días consecutivos. Los animales se distribuyeron al azar a uno de los seis tratamientos: A) fracción de plasma seminal con PM >30 kDa, B) fracción de plasma seminal con PM entre 10 y 30 kDa, C) fracción de plasma seminal con PM entre 5 y 10 kDa, D) fracción de plasma seminal con PM <5 kDa, E) plasma seminal completo, y F) PBS. Los animales fueron tratados con una solución de 1.5 ml de la fracción de plasma seminal o placebo correspondiente por vía intramuscular. Las llamas fueron evaluadas por ecografía en el día 2 y 9...

El presente estudio fue realizado con el propósito de evaluar el efecto de varias fracciones de plasma seminal de llamas, según su peso molecular (PM), sobre la inducción de la ovulación. Se utilizó 54 llamas hembras sin cría y en óptimo estado reproductivo, con folículo dominante >7 mm de diámetro determinado por ecografía transrectal por tres días consecutivos. Los animales se distribuyeron al azar a uno de los seis tratamientos: A) fracción de plasma seminal con PM >30 kDa, B) fracción de plasma seminal con PM entre 10 y 30 kDa, C) fracción de plasma seminal con PM entre 5 y 10 kDa, D) fracción de plasma seminal con PM <5 kDa, E) plasma seminal completo, y F) PBS. Los animales fueron tratados con una solución de 1.5 ml de la fracción de plasma seminal o placebo correspondiente por vía intramuscular. Las llamas fueron evaluadas por ecografía en el día 2 y 9 post-tra...

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The objective of the study was to compare the ovulatory response and embryo production in llamas (Lama glama) treated with a single dose of equine chorionic gonadotropin (eCG) alone or combined with intravaginal medroxyprogesterone acetate (MPA) at the time of follicular wave emergence. Llamas with a growing follicle ≥7 mm in diameter were assigned to one of the following groups: (1) Control (n = 28): Nonstimulated llamas were mated and embryos were collected 7 d after mating. (2) eCG (n = 32): Llamas were given 5 mg luteinizing hormone (LH) (Day 0) to induce ovulation, 1000 IU eCG on Day 2, a luteolytic dose of prostaglandin F2α on Day 6, mating on Day 7, and embryo collection on Day 14. (3) eCG+MPA (n = 34): Llamas were treated as those in the eCG group, but a sponge containing 60 mg MPA was placed intravaginally from Days 2 to 6. Llamas that did not respond to synchronization or su...

Recent studies document the LH-releasing pathway of nerve growth factor (NGF) in male camelids and that the LH response to seminal NGF is associated with elevated plasma testosterone concentration. Results provide rationale for the hypothesis that NGF in semen is associated with male fertility. In Experiment 1, the association between the amount of NGF in the ejaculate and characteristics of the male reproductive system was examined in alpacas. The concentration of NGF was measured by radioimmunoassay in semen samples collected from male alpacas (n = 47) and correlated with sperm morphology and motility, and measurements of the male reproductive anatomy. Most ejaculates had NGF concentrations that, based on previous studies, triggered ovulation in female camelids, however, we only found a positive correlation between NGF concentration with sperm concentration, thread formation and to...