Ovulation-Inducing Factor in the Seminal Plasma of Alpacas and Llamas1

Abstract

Studies were conducted to document the existence of an ovulation-inducing factor in the seminal plasma of alpacas (experiment 1) and llamas (experiment 2) and to determine if the effect is mediated via the pituitary (experiment 3). In experiment 1, female alpacas (n = 14 per group) were given alpaca seminal plasma or saline intramuscularly or by intrauterine infusion. Only alpacas that were given seminal plasma i.m. ovulated (13/ 14, 93%; P < 0.01). In experiment 2, ovulation was detected in 9/10 (90%) llamas at a mean of 29.3 +/- 0.7 h after seminal plasma treatment. Plasma progesterone concentrations were maximal by Day 9 and were at nadir by Day 12 posttreatment. In experiment 3, female llamas were given llama seminal plasma, GnRH, or saline i.m., and ovulation was detected in 6/6, 5/ 6, and 0/6 llamas, respectively (P < 0.001). Treatment was followed by a surge (P < 0.01) in plasma LH concentration beginning 15 min and 75 min after treatment with GnRH and seminal plasma, respectively. Plasma LH remained elevated longer in the seminal plasma group (P < 0.05) and had not yet declined to pretreatment levels after 8 h. Compared with the GnRH group, corpus luteum tended to grow longer and to a greater diameter (P = 0.1) and plasma progesterone concentration was twice as high in the seminal plasma group (P < 0.01). Results document the existence of a potent factor in the seminal plasma of alpacas and llamas that elicited a surge in circulating concentrations of LH and induced an ovulatory and luteotropic response.

Polyandry Promotes Enhanced Offspring Survival in Decorated Crickets

“…Third, sperm of certain males sometimes might be genetically incompatible with a female's ova (Kraaijeveld-Smit et al 2002;Zeh and Zeh 2003;Mays and Hill 2004;Pryke et al 2010). Fourth, semen might contain certain chemicals that help to induce ovulation at the optimal time for conception (Chen et al 1985;Adams et al 2005). If polyandry increases female ARS, then the frequency of polyandry should positively correlate with the number of fitness components (n ¼ 4 that I measured for prairie dogs) that are favorably affected.…”

Dynamic digestive physiology of a female reproductive organ in a polyandrous butterfly

“…Nevertheless, researchers have begun identifying a number of female physiological traits that may serve as counteradaptations to male ejaculatory substances. These include secreted proteases that may function to dislodge male copulatory plugs and/ or de-activate manipulative ejaculate compounds (Kelleher et al, 2007, female receptors and associated hormonal processes that respond to male ejaculate constituents (Adams et al, 2005;Yapici et al, 2008) and morphological features of the female reproductive tract that could play a role in cryptic female choice via their effect on male fertilization success and sperm competition (Pitnick et al, 2003).…”

Tasa De Ovulación Utilizando Liberador De Gonadotropinas Y Plasma Seminal en Alpacas Y Llamas

“…Por otro lado, la existencia del factor inductor de ovulación (FIO) fue demostrado al aplicar plasma seminal en forma intramuscular en alpacas y llamas, logrando 93 y 90% de ovulaciones en alpacas y llamas, respectivamente (Adams et al, 2005), mientras que Ratto et al (2006b) obtuvo el 100% de ovulaciones en llamas y alpacas.…”