Effect of treatment with progesterone and oestradiol when starting treatment with an intravaginal progesterone releasing insert on ovarian follicular development and hormonal concentrations in Holstein cows
Introduction
Fertility and synchrony of oestrus can be affected in cattle by the stage of development of preovulatory ovarian follicles when pro-oestrus is induced. Cows with preovulatory follicles that are still in a growing phase of development at the onset of pro-oestrus take longer to enter oestrus than cows that have follicles that have plateaued in their growth (Austin et al., 1999). Fertility is reduced at a synchronised oestrus when dominant follicles persist on the ovary for extended periods of time (Savio et al., 1993, Stock and Fortune, 1993, Mihm et al., 1994; Cooperative Regional Research Project, NE-161, 1996; Austin et al., 1999). This is thought to be related to detrimental effects on the oocyte with a subsequent increase in embryonic loss rates (Ahmad et al., 1995).
Methods to induce precise synchrony of oestrus with normal fertility have concentrated on producing a homogenous population of follicles with a short duration of dominance (<10 days) at the onset of pro-oestrus (Roche et al., 1999). Both treatment with oestradiol (E2) and progesterone (P4) have been used for this purpose. Treatment with E2 has resulted in the consistent emergence of a new follicular wave 3–5 days (mean of 4.3 days) after treatment (Bo et al., 1995) regardless of the stage of development of the dominant follicle at the time of treatment. Treatment with P4 has resulted in emergence of a new follicular wave 2–5 days after treatment (Cavalieri et al., 1997, Cavalieri et al., 1998, McDowell et al., 1998, Cavalieri et al., 2001). In one study treatment with P4 was less successful in inducing new wave emergence in cows in which follicles were in a growing phase of development compared to cows in which follicles had reached a plateau phase of growth (Cavalieri et al., 1998). Studies that have examined the effects of P4 and E2 on follicular development in cattle have been undertaken in different types of cattle with ovarian follicles at different stages of follicular development. There are no studies that have examined the effects of both P4 and E2 on ovarian follicular development when administered to Holstein cows at random stages of the oestrous cycle.
Although administration of E2 and P4 has improved the synchrony of emergence of a new follicular wave compared to untreated control cows, intervals to new wave emergence and oestrus are still variable (Roche et al., 1999). One method that has been used to reduce the variation in intervals to oestrus following treatment is to synchronise a preovulatory rise in concentration of E2 during pro-oestrus (Roche et al., 1999, Lane et al., 2001). The principle of controlling follicle emergence and synchronising pro-oestrus has been developed into an oestrous synchronisation treatment that involves treatment with an intravaginal progesterone releasing insert (IVP4) for 7 days, PGF2α at device removal and administration of oestradiol benzoate (ODB) at the time of device insertion and 24–48 h after device removal. An oestrous detection rate of 95.7% and a pregnancy rate of 57.8% were recorded using such a system in dairy cows in New Zealand (Day et al., 2000). That study found that pregnancy rates of cows that were in oestrus 24–48 h after removal of inserts tended to be lower than cows that were detected in oestrus later in the synchrony period. This reduction in pregnancy rate was speculated to be due to an inability of the ODB administered at the start of the treatment with an IVP4 to cause atresia of dominant ovarian follicles and emergence of a new follicular wave during the treatment period. Doubt was therefore raised in this study as to whether or not exogenous treatment with ODB was providing optimal control of follicular wave emergence during the synchrony treatment.
The objectives of this study were to determine if the pattern of ovarian follicular development and changes in concentrations of P4, E2, LH and FSH in plasma differed following the administration of P4 and/or E2 at the time of commencing a treatment to synchronise oestrus in dairy cows that also involved induction of oestrus with an injection of ODB.
Section snippets
Oestrous synchronisation protocol
Qestrus was synchronised in 34 non-lactating, non-pregnant Holstein cows using four different treatment protocols in a 2 by 2 factorial arrangement. Each cow was treated with an intravaginal hormone release device (CIDR cattle device, Genetics Australia, Bacchus Marsh, Vic.) for 7 days, 0.5 mg of cloprostenol IM (CIDR-PG, Genetics Australia, Bacchus Marsh, Vic.) at the time of removal of inserts and 1.0 mg of ODB IM (Cidirol, Genetics Australia, Bacchus Marsh, Vic.) 24 h after removal of inserts.
Ultrasonography
Every cow with the exception of one cow treated with both P4 and ODB was detected in oestrus within 96 h of removing inserts (97.1%; (33/34)). Ovulation was detected in this cow 2.5 days after removing inserts. The proportion of cows within each group that ovulated within 96 h of removing inserts was 50% (4/8), 77.8% (7/9), 50% (4/8) and 77.8% (7/9) for the control, P4, ODB, and P4+ODB groups, respectively (P=0.41).
A corpus luteum was observed in 94.1% (32/34) of the cows using ultrasonography
Discussion
The results of this study provide evidence that the pattern of ovarian follicular development and concentrations of gonadotrophins differ following treatment with P4 or ODB at the time of starting treatment with an IVP4 device. While treatment with P4 or ODB improved the synchrony of follicular wave emergence, the synchrony of wave emergence was greater following administration of ODB compared to P4. An unexpected finding in this study was the occurrence of anovulatory oestrus in 35% of the
Conclusion
Injecting ODB at the time of starting treatment with an IVP4 device resulted in greater suppression of mean concentrations of LH, a more synchronous emergence of a new follicular wave, a shorter interval from emergence to ovulation and reduced diameter of the ovulatory follicle compared with cows treated with P4 at the start of treatment. There was no evidence that combining treatment of ODB with P4 had any significant effect on follicular dynamics compared to treatment with ODB alone when
Acknowledgements
We thank T. Squires and T. Moyes for technical assistance, J. Borman and F. Davidson for performing assays and A. Rabiee for providing the progesterone injection. We thank D. Robertson for supervision of and description of the FSH assay. Financial support was provided under the Strategic Partnerships with Industry Research and Training Scheme, of the Australian Research Council and the Department of Education, Training and Youth Affairs. We thank the industry partners Genetics Australia and
References (30)
- et al.
Follicular wave dynamics after estradiol-17β treatment of hiefers with or without a progstogen implant
Theriogenology
(1994) - et al.
Exogenous control of follicular wave emergence in cattle
Theriogenology
(1995) - et al.
Oestradiol potentiates a prolonged progesterone-induced suppression of LH release in ovariectomised cows
Anim. Reprod. Sci.
(1996) - et al.
Ovarian responses to progesterone and oestradiol benzoate administered intravaginally during dioestrus in cattle
Anim. Reprod. Sci.
(1999) - et al.
Effects of maturity of the potential ovulatory follicle on induction of oestrus and ovulation in cattle with oestradiol benzoate
Anim. Reprod. Sci.
(2001) - et al.
Ovarian follicular development following administration of progesterone or aspiration of ovarian follicles in Holstein cows
Theriogenology
(2001) - et al.
The effect of estradiol benzoate on synchrony of estrus and fertility in cattle after removal of a progesterone releasing intravaginal device
Theriogenology
(2001) - et al.
The effect of dose and route of oestradiol benzoate administration on plasma concentrations of oestradiol and FSH in long-term ovariectomised heifers
Anim. Reprod. Sci.
(2000) - et al.
Effect of treatment with progesterone and oestradiol benzoate on ovarian follicular turnover in postpartum anoestrous cows and cows which have resumed oestrous cycles
Anim. Reprod. Sci.
(2002) - et al.
Role of inhibin in the regulation of FSH secretion and folliculogenesis in cows
Anim. Reprod. Sci.
(1996)
Effect of progesterone on ovarian follicles, emergence of follicular waves and circulating follicle-stimulating hormone in heifers
J. Reprod. Fertil.
Effect of persistent follicles on early embryonic losses in beef cows
Biol. Reprod.
Effect of duration of dominance of the ovulatory follicle on onset of estrus and fertility in heifers
J. Anim. Sci.
Use of a low dose of estradiol benzoate during diestrus to synchronise development of the ovulatory follicle in cattle
J. Anim. Sci.
Effect of 48 h treatment with 17β-oestradiol or progesterone on follicular wave emergence and synchrony of ovulation in Bos indicus cows when administered at the end of a period of progesterone treatment
Anim. Reprod. Sci.
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2020, Animal Reproduction ScienceCitation Excerpt :With these types of treatment regimens, there is use of estradiol to synchronize the stage of follicular wave dynamic changes combined with the use of intravaginal P4 devices (IVPD) for 7 or 8 d (Bo et al., 1994; Burke et al., 1996), PGF2α administration at the time of IVPD removal and administration of estradiol or GnRH to induce ovulation. Several factors, such as parity and milk production (Stevenson et al., 2016), stage of the estrous cycle (Bisinotto et al., 2010; Denicol et al., 2012), response to the first GnRH (Vasconcelos et al., 1999; Moreira et al., 2001) or estradiol benzoate (EB) administration (Cavalieri et al., 2003), P4 concentrations during the period of follicular growth (Rivera et al., 2011; Santos et al., 2016), regression of the CL after PGF2α treatment (Martins et al., 2011; Wiltbank et al., 2015), concentrations of estradiol and follicle size at ovulation (Bello et al., 2006), ovulatory response after the second GnRH (Pursley et al., 1997) and estradiol (Souza et al., 2009) administrations affect fertility when imposing different treatment regimens for TAI. In countries where estrogens continue to be approved for synchronization of ovulation and TAI in lactating dairy cows, treatment regimens in which there is combining of either GnRH or EB with IVPD are used to synchronize the stage of follicular wave dynamics among cows.
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