- Published:
Follicular Development and Ovulation in Sows: Effect of hCG and GnRH Treatment
Acta Veterinaria Scandinavica volume 36, pages 123–133 (1995)
Abstract
Follicular growth, chronology of ovulation and embryo morphology were compared in sows ovulating spontaneously and sows, in which the ovulation was attempted induced by hCG or GnRH.
Indwelling catheters were placed on day 1 (weaning = day 0) in the ear veins of 18 sows, which were then randomly divided into 3 groups: a control group (N = 6), a group (N = 6) given 750 iu hCG (Physex®) im 76h after weaning (hCG group) and a group (N = 6) given 500 µg GnRH (Fertagyl®) im 76h (N = 3) or 100h after weaning (N = 3) (GnRH group). Follicular diameter and time of ovulation were monitored by ultrasonography every 4h from day 3 until ovulation or development of cysts by means of a sector scanner fitted with a 5.0/7.5 MHz multiangle probe. Heat detection was performed every 8h from day 3 until ovulation. On day 13, the sows were slaughtered, the number of corpora luteae (CL) was counted, and embryos were flushed from the uteri. The control group showed clear heat symptoms, and on day 3, the follicles were typically 3–7 mm and grew up to 7–10 mm over 2 days, where they remained for approximately 24h until ovulation took place 41h ± 9h after first sign of standing heat. The hCG group exhibited no signs of heat, and the follicles only reached 5–8 mm in diameter at time of ovulation, which occurred 40h ± lh after hCG-injection. The GnRH group exhibited inconsistent signs of heat, and the follicles reached a maximum size of 7–12 mm in diameter where they remained for more than 24h. Only 2 sows in this group ovulated within 84–92h after the GnRH injection, and development of bursa cysts and cystic follicles was a common finding. The average number of CL was 18.2 ±5.7 per sow (N = 16, range: 3–27) with no significant difference between the groups. Total embryo recovery was 79 ± 13 % with no significant difference between groups. The embryo diversity calculated as standard deviation of the maximum diameter was higher in the hCG group as compared with the control group.
It is concluded that (1) transrectal ultrasonography can be used in sows for accurate assessment of follicular growth and ovulation; (2) the use of hCG results in lack of heat symptoms and reduced follicle size at the time of ovulation when injected 76h after weaning; (3) administration of a single injection of GnRH, if given before the first signs of heat, results in inconsistent heat symptoms and no or late ovulations.
References
Bazer FW, Thather WW, Martinalt-Botte F, Terqui M: Conceptus development in large white and prolific Chinese Meishan pigs. J. Reprod. Fert. 1988, 84, 37–42.
Brussow K-P, Ratky J, Kanitz W, Becker F: Determination of the duration of ovulation in gilts by means of laparoscopy. Reprod. dom. Anim. 1990, 25, 184–190.
Brussow K-P, Ratky J: The duration of ovulation in GnRH-treated gilts following seminal plasma infusion. Reprod. dom. Anim. 1992, 23, 119–122.
Brussow K-P, Schneider F, Ratky J: The influence of longtime active GnRH-agonist on hormonal level and follicular development in cyclic gilts. Reprod. dom. Anim. 1994, 29, 358–361.
Cardenas H, Pope WF: Effect of time of mating relative to ovulation on oorphological diversity of swine blastocysts. Biol. Reprod. 1993, 49, 1015–1018.
Cran DG: Qualitative and quantitative structural changes during pig oocyte maturation. J. Reprod. Fert. 1985, 74, 237–245.
Ford SP, Schwartz NK, Rothschild MF, Conley AJ, Warner CM: Indfluence of SLA haplotype on preimplantation embryonic cell number in miniature pigs. J. Reprod. Fert. 1988, 84, 99–104.
Galvin JM, Wilmut I, Day BN, Ritchie M, Thomson M, Haley CS: Reproductive performance in relation to uterine and embryonic traits during early gestation in Meishan, Large White and crossbred sows. J.Reprod. Fert. 1993, 98, 377–384.
George G: Grundlagen untersuchungen zur biotech- nischen Steuerung der Ovarfunktion bei Jung- sauen mit GnRH vet “Berlin-Chemie”. (Basic studies into biotechnological control of ovarian function in gilts using GnRH vet “Berlin- Chemie”). Vet Med. 1985, 40, 852–853.
Grant SA, Hunter MG, Foxcroft GR: Morphological and biochemical characteristics during ovarian follicular development in the pig. J. Reprod. Fert. 1989, 86, 171–183.
Hunter RHF, Polge C: Maturation of follicular oocytes in the pig after injection of hCG. J. Reprod. Fert. 1966, 12, 525–531.
Hunter RHF: Chronological and cytological details of fertilization and early embryonic development i the domestic pig, sus scrofa, Anat. Rec. 1974, 178, 169–186.
Hunter RHF, Cook B, Baker TG: Dissociation of response to injected gonadotropin between the Graafian follicle and oocyte in pigs. Nature 1976, 260, 156–158.
Hunter MG, Wiesak T: Evidence for and implications of follicular heterogeneity in pigs. J. Reprod. Fert. 1990, Suppl. 40, 163–177.
Hunter MG, Briggs C, Foxcroft GR, McNeilly AS, Tilton JE: Comparisons of endocrinology and behavioural events during the periovulatory period in Meishan and Large-White hybrid gilts. J.Reprod.Fert. 1993, 97, 475–480.
Lutz JB, Rampacek GB, Kraeling RR: Induction of ovulation in prepuberal gilt by pulsatile administration of gonadotropin releasing hormone. Dom. Anim. Endocrinology 1985, 2, 61–65.
Oxenreider SL, Day BN: Transport and cleavage of ova in swine. J.Anim.Sci 1965, 24, 413–417.
Pope WF, First NL: Factors affecting the survival of pig embryos. Theriogenology 1985, 23, 91–105.
Pope WF, Wilde HW, Xie S: Effect of electrocautery of nonovulated day 1 follicles on subsequent morphological variation among day 11 embryos. Biol. Reprod. 1988a, 39, 882–887.
Pope WF: Uterine Asynchrony: A cause of embryonic loss. Biol Reprod. 1988b, 39, 999–1003.
Pope WF, Xie S, Broermann DM, Nephew KP: Causes and consequences of early embryonic diversity in pigs. J. Reprod. Fert. 1990, Suppl. 40, 251–260.
SAS Institute Inc.: SAS/STAT®, Version 6, (4th ed.), Cary, NC 1990.
Soede NM, Van der Lende T, Kemp B, De Koning M: Assessment of the duration of ovulation in sows using ultrasonography, Assisted Reproductive Technology and Andrology, 1991, 2, 128–129.
Soede NM, Noordhuizen JPTM, Kemp B: The duration of ovulation in pigs, studied by transrectal ultrasonography, is not related to early embryonic diversity. Theriogenology 1992, 38, 653–666.
Soede NM, Hazeleger W, van der Lende T, Kemp B: The influence of insemination conditions on embryonic diversity in gilts depends on their social condition. Reprod. dom. Anim. 1993, 28, 217–224.
Spalding JF, Berry RO, Moffit JI: The maturation process of the ovum of swine during normal and induced ovulation, J.Animal Sci. 1955,14, 609–620.
Thorup F: Referencevaerdier for soens reproduk- tion. (Reference values for reproduction in the sow). Dansk Vet.tidsskr. 1990, 73, 958–963.
Wagner-Rietschel H: Studies on the oestrus and ovulation of sows using transcutaneous sonography. Dissertation, 1991, Veterinary Faculty Hannover, Germany.
Van der Meulen J., Helmond FA, Oudenaarden CPJ: Corpus luteum function in the pig: Progesterone profiles of cyclic and pregnant gilts. Nl. J. Agr. Sci. 1990, 33, 45–42.
Weitze KF, Habech O, Willmen T, Rath D: Detection of ovulation in the sow using transcutaneous sonography. Zuchthyg. 1989, 24, 40–42.
Wiesak T, Hunter MG, Foxcroft GR: Differences in follicular morphology, steroidogenesis and oocyte maturation i naturally cyclic and PMSG/ hCG-treated prepubertal gilts. J.Reprod. Fert. 1990, 89, 663–641.
Wilde HW, Xie S, Day ML, Pope WF: Survival of Small and Large Littermate Blastocysts in Swine after Synchronous and Asynchronous Transfer Procedures. Theriogenology 1988, 30, 1069–1074.
Wilmut I, Haley CS, Ashworth CJ, Aitken RP, Ritchie W: Embryo development and embryo transfer in Meishan and Large White Pigs. In: Hill WG, Thomson R, Williams JA (eds.). Proc. 4th World Congress on Genetics Applied to Livestock Production. Edinburgh 1990, 347–350
Wilmut I, Ritchie W, Haley CS, Ashworth CJ, Aitken RP: A comparison of rate and uniformity of embryo development in Meishan and Large White pigs. J. Reprod. Fert. 1990, 95, 45–56.
Xie S, Broermann DM, Nephew KP, Bishop MD, Pope WF: Relationship between oocyte maturation and fertilization on zygotic diversity in swine. J.Anim. Sci. 1990a, 68, 2027–2033.
Xie S, Pope WF, Broermann DM, Nephew KP, Geisert RD: Ovulation and early embryogenesis in Swine. Biol. Reprod. 1990b, 43, 236–240.
Acknowledgments
Thanks to Erika Busch, Inger Heinze and Hanne Tinggård for technical assistance. Nicoline Soede is thanked for comments and encouragement.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Nissen, A., Lehn-Jensen, H., Hyttel, R. et al. Follicular Development and Ovulation in Sows: Effect of hCG and GnRH Treatment. Acta Vet Scand 36, 123–133 (1995). https://doi.org/10.1186/BF03547709
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1186/BF03547709