Recent advancements in the hormonal stimulation of ovulation in swine

Abstract

Induction of ovulation for controlled breeding is available for use around the world, and conditions for practical application appear promising. Many of the hormones available, such as human chorionic gonadotropin (hCG), gonadotropin-releasing hormone (GnRH) and its analogs, as well as porcine luteinizing hormone (pLH), have been shown to be effective for advancing or synchronizing ovulation in gilts and weaned sows. Each of the hormones has unique attributes with respect to the physiology of its actions, how it is administered, its efficacy, and approval for use. The timing for induction of ovulation during the follicle phase is critical as follicle maturity changes over time, and the success of the response is determined by the stage of follicle development. Female fertility is also a primary factor affecting the success of ovulation induction and fixed time insemination protocols. Approximately 80%–90% of female pigs will develop mature follicles following weaning in sows and synchronization of estrus in gilts. However, those gilts and sows with follicles that are less developed and mature, or those that develop with abnormalities, will not respond to an ovulatory surge of LH. To address this problem, some protocols induce follicle development in all females, which can improve the overall reliability of the ovulation response. Control of ovulation is practical for use with fixed time artificial insemination and should prove highly advantageous for low-dose and single-service artificial insemination and for use with frozen-thawed and sex-sorted sperm.

Development of Elisa for the Quantitative Determination of the Porcine Follicle-Stimulating Hormone in Biological Liquids

“…По данным специализированной литературы физиологические значения концентрации ФСГ у половозрелых свиней изменяются в диапазоне от 0,7 до 7 нг/мл [8], что входит в диапазон физиологической нормы и у человека. Таким образом, при подборе условий проведения ИФА учитывали необходимость получения чувствительности системы не более 0,5 нг/мл.…”

The Alterations of Endometrial and Myometrial Receptivity in Early Pregnant Gilts in Response to Estrus Induction With PMSG/hCG

“…Induced ovulation is of great interest in the commercial swine industry being a useful tool for improving production e ciency and facilitating animal management. It ensures xed-time arti cial insemination and may serve as a gateway technology for the use of cryopreserved boar semen and sex-sorted semen [1,2]. Additionally, control of estrus is a fundamental technique in the preparation of embryo donors and recipients in the application of transgenesis, nuclear transfer, and other reproductive biotechniques.…”

Application of modern estrus detection protocols in small scale Hybrid Black pig production systems

“…A missed insemination opportunity translates to additional 21 days of feeding an unproductive sow, increased number of non-productive days and reduced number of piglets harvested per sows per year (King et al, 1998;Andersson et al, 2016). Consequently, drugs to induce ovulation (Knox, 2015;Andersson et al, 2016) and other high-tech estrus detection protocols such as sensors, pedometers, pudendal images and ultrasound have since been introduced with an aim of replacing the traditional labour intensive and unreliable estrus detection techniques.…”

“…However, we must realize that the applicability of such estrus detection protocols in some parts of the world may be limited, particularity in the developing world where production is mainly dominated by small scale producers, due to lack of financial resources and inavailability of skilled labour (Simões et al, 2014;Knox, 2015). Furthermore, the utilization of hormones might be dependent on the regulatory approval in that particular country.…”