Pre-synchronization of ovulation timing and delayed fixed-time artificial insemination increases pregnancy rates when sex-sorted semen is used for insemination of heifers

Oosthuizen, Nicola; Fontes, P. L. P.; Filho, R.V. Oliveira; Dahlen, Carl R; Grieger, David M.; Hall, J.B.; Lake, Scott; Looney, C.R.; Mercadante, Vitor R G; Neville, B. W.; Perry, George A.; Powell, J. G.; Prezotto, Ligia D.; Seidel, G.E.; Walker, R.S.; Cardoso, Rodolfo C.; Pohler, K. G.; Lamb, G. C.

doi:10.1016/j.anireprosci.2021.106699

Cited by 10 publications

(17 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Pregnancy rates to TAI are greater in cows and heifers that express estrus before TAI, where PR/AI between 11% and 43% greater have been reported ( Perry et al, 2007 ; Richardson et al, 2016 ; Oosthuizen et al, 2020 , 2021 ). Therefore, it was expected that PR/AI in the present experiment would be greater in heifers that expressed estrus when compared with those that did not express estrus.…”

Section: Discussionmentioning

confidence: 92%

Effects of prolonging the interval from progestin removal to prostaglandin F2α injection from 16 to 17 d in a long-term estrus synchronization protocol in beef heifers

Oosthuizen

Melo

Seidel

et al. 2021

Translational Animal Science

Self Cite

View full text Add to dashboard Cite

To determine effects of delaying the injection of prostaglandin F2α (PGF) and fixed-time artificial insemination (TAI) in the 14-d CIDR-PG protocol, 1,049 Angus heifers at six locations were enrolled in a completely randomized design. Within location heifers were randomly assigned to one of two treatment groups: 1) PG16 (n = 518), heifers received a controlled internal drug release (CIDR) insert on d 0 for 14 d, a 25-mg injection of PGF 16 d after CIDR removal (Day 30), and a 100-µg injection of gonadotropin-releasing hormone concurrent with TAI 66 ± 2 h later; or 2) PG17 (n = 531), heifers were treated the same as PG16, however, PGF was administered 17 d after CIDR removal (Day 31), and heifers were TAI 66 ± 2 h later. Estrus detection patches were applied to a subset (n = 482) of heifers at the time of PGF administration and were examined for activation at TAI. Dominant follicle diameter was determined via transrectal ultrasonography at PGF administration and TAI in a subset of heifers (n = 116). Transrectal ultrasonography was performed to determine pregnancy rates to TAI (PR/AI) between 30 and 45 d after TAI. Estrus expression prior to TAI differed by treatment where PG17 heifers had greater (P < 0.01) expression of estrus than PG16 heifers (57.8 ± 6.1 vs. 43.4 ± 6.1%, respectively). Nevertheless, dominant follicle diameters at PGF and at TAI were similar (P ≥ 0.59) between PG16 and PG17 heifers. In addition, PR/AI did not differ (P = 0.29) between PG16 and PG17 treatments (50.5 ± 3.2 vs. 45.7 ± 3.1%, respectively). Results of this experiment indicate that delaying the injection of PGF and TAI in the 14-day CIDR-PG protocol increased estrus expression prior to TAI yet did not improve fertility in beef heifers.

show abstract

Section: Discussionmentioning

confidence: 92%

Effects of prolonging the interval from progestin removal to prostaglandin F2α injection from 16 to 17 d in a long-term estrus synchronization protocol in beef heifers

Oosthuizen

Melo

Seidel

et al. 2021

Translational Animal Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…In heifers without presynchronization, lower P/AI could be owing to asynchronized follicle development at the beginning of Cosynch protocol leading to ovulation of aged follicle in CIDR-4 group than that in CIDR-5 group in which asynchronized dominant follicle development could be slowed down with immediate CIDR insertion. Likewise, Oosthuizen et al [ 28 ] reported increase in P/AI following presynchronization with PGF2α seven days prior to 7 days Cosynch CIDR protocol involving TAI with sex-sorted semen 72 h after from CIDR removal in beef heifers. In contrast, similar P/AI between pre-synchronized and not pre-synchronized heifers could indicate no beneficial effect of presynchronization in CIDR-5 group.…”

Section: Discussionmentioning

confidence: 99%

Effect of One-Day Delaying CIDR Administration in 5-Day Cosynch Protocol in Dairy Heifers

Pancarcı

Güngör

Harput³

et al. 2021

Animals

View full text Add to dashboard Cite

Effect of one-day delaying progesterone administration at the beginning of 5-day Cosynch protocol was investigated in Holstein heifers for the first artificial insemination (AI). Heifers received a synchronized ovulation and timed AI (TAI) with CIDR inserted on day (d) 0 (CIDR-5; n = 206) or d 1 (CIDR-4; n = 192). In both group, GnRH was administered on d 0 followed by a single PGF2α injection and CIDR removal five days later from GnRH. On d 8, TAI and GnRH administration were concurrently conducted. Heifers detected in estrus up to 24 h prior to TAI were inseminated without GnRH administration. Rates of ovulation, accessory CL formation and new dominant follicle development following initial GnRH injection did not differ between groups. P/AI did not differ between CIDR-4 (44.3%, [85/192]) and CIDR-5 (51.9%, [107/206]) groups, respectively. Pregnancy per AI (P/AI) was significantly (p < 0.01) declined as heifers’ age (12–13, 14, 15, 16 and17–21 months) proceeded in CIDR-4 group (55.6%, 52.1%, 37.9%, 35.7%, 32.4%) compared to those in CIDR-5 group (60.0%, 50.0%, 53.9%, 51.5%, 46.2%) respectively. In conclusion, there is no benefit for delaying CIDR administration in 5-day Cosynch protocol in dairy heifers. However, higher P/AI in CIDR-5 group in older heifers can be considered for reproductive management.

show abstract

“…Recent experiments among heifers have suggested delaying FTAI with sexed semen could potentially result in improvements to P/AI, but that these improvements have been protocol-dependent. When administering PG 7 days prior to the 7-Day CO-Synch + CIDR protocol and delaying insemination with sexed semen from 54 h to 72 h, an improvement in P/AI with sexed semen was observed among heifers (Oosthuizen et al, 2021). A greater proportion of heifers that did not receive presynchronization had expressed estrus prior to FTAI when FTAI was performed at 72 h compared to 54 h.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of the 7 and 7 synch protocol for control of the estrous cycle among beef cows prior to fixed-time artificial insemination with sex-sorted or conventional semen

Andersen¹

View full text Add to dashboard Cite

Experiment 1 was conducted to compare 7 and 7 Synch and the 7-day CO-Synch + controlled internal drug release (CIDR[copyright]) protocols prior to fixed-time artificial insemination (FTAI) of beef cows with conventional or sex-sorted semen. Cows (n = 1,538) were blocked based on age and days postpartum (DPP) and randomly assigned to protocol and semen type. Cows assigned to 7-day CO-Synch + CIDR (n = 769) received administration of gonadotropin-releasing hormone (GnRH) and insertion of an intravaginal progesterone-releasing insert (CIDR) on Day -10, and administration of prostaglandin F2[alpha] (PG) coincident with CIDR removal on Day -3. Cows assigned to 7 and 7 Synch (n = 769) received PG and insertion of CIDR on Day -17, GnRH on Day -10, and PG coincident with CIDR removal on Day -3. Estrus detection aids were applied to all cows. Cows received FTAI 66 h after CIDR removal with conventional (20 x 106 cells per unit) or sex-sorted (4 x 106 cells per unit) semen. Estrus expression was affected by protocol (P = 0.01) by protocol x DPP (P = 0.0004), with 7 and 7 Synch (82 percent; 629/769) resulting in a greater proportion of cows expressing estrus (82 percent [629/769] versus 64 percent [492/769]), especially among cows with greater DPP. Pregnancy rates to FTAI were reduced (P < 0.0001) when using sex-sorted semen but greater among cows treated with 7 and 7 Synch (conventional semen: 72 percent [280/389]; sex-sorted semen: 52 percent [199/380]) compared with 7-day CO-Synch + CIDR (conventional semen: 61 percent [233/383]; sex-sorted semen: 44 percent [171/386]). Experiment 2 was designed to evaluate later timing of fixed-time artificial insemination (FTAI) with sex-sorted semen among postpartum beef cows following the 7 and 7 Synch protocol, with the hypothesis that later timing would result in increased pregnancy rates (P/AI) among cows that expressed estrus prior to FTAI. Beef cows (n=414) were blocked based on age and days postpartum (DPP) and randomly assigned to receive FTAI at 66 or 72 h after administration of prostaglandin F2[alpha] (PG). Estrus was synchrized using the 7 and 7 Synch protocol, which consists of administration of PG (500 [mu]g cloprostenol) and insertion of an intravaginal progesterone-releasing insert (CIDR; 1.38 g progesterone) on Day 0, gonadotropin-releasing hormone (GnRH; 100 [mu]g gonadorelin) on Day 7, and PG coincident with CIDR removal on Day 14. Estrus detection aids (EstrotectTM) were applied to all cows on Day 14, and activation status was recorded at fixed-time artificial insemination (FTAI) on Day 17. All cows that expressed estrus prior to FTAI received sex-sorted semen (4 x 106 cells per unit; SexedULTRA 4MTM). The proportion of cows expressing estrus prior to FTAI did not differ between treatments at this power of test (66 h: 71 percent [146/205]; 72 h: 76 percent [158/209]). Additionally, P/AI of estrous cows inseminated with sex-sorted semen did not differ between treatments (66 h: 45 percent [68/146]; 72 h: 40 percent [63/158]). In conclusion, later timing of FTAI following the 7 and 7 Synch protocol failed to improve P/AI of estrous cows inseminated h sex-sorted semen.

show abstract

Pre-synchronization of ovulation timing and delayed fixed-time artificial insemination increases pregnancy rates when sex-sorted semen is used for insemination of heifers

Cited by 10 publications

References 34 publications

Effects of prolonging the interval from progestin removal to prostaglandin F2α injection from 16 to 17 d in a long-term estrus synchronization protocol in beef heifers

Effects of prolonging the interval from progestin removal to prostaglandin F2α injection from 16 to 17 d in a long-term estrus synchronization protocol in beef heifers

Effect of One-Day Delaying CIDR Administration in 5-Day Cosynch Protocol in Dairy Heifers

Evaluation of the 7 and 7 synch protocol for control of the estrous cycle among beef cows prior to fixed-time artificial insemination with sex-sorted or conventional semen

Contact Info

Product

Resources

About