providing fence-line exposure to sows for approximately 20 min daily. Nose-to-nose contact was permitted but not full body contact. For each sow, BPT was performed in the presence of a boar by an experienced technician and behavioral estrus response was evaluated using a scale of 0 to 2: 0, representing no response/interest or immobilization, 1, representing some response/interest or partial immobilization, and 2, showing signs of lordosis as indication of estrus. For TRT1 and TRT2 groups, sows were observed for signs of estrus daily beginning 3 d post-weaning using the same scale previously described in response to the BPT in the absence of a boar. Sows that exhibited lordosis were considered in estrus. Wean-to-estrus interval was determined as the interval from weaning (h 0) until the time that estrus was first detected (i.e., score of 2). OvuGel® preparation and administration. Sows were treated with 2 mL of OvuGel (200 µg triptorelin acetate) given intravaginally 96 h post-wean. OvuGel was stored at approximately 6° C and warmed to room temperature at least 10 min prior to administration to allow adequate viscosity of the gel. The OvuGel bottle was then placed onto the commercially available applicator (JBS United Animal Health, LLC) allowing the bottle mount to puncture and enable withdrawal of the gel. A delivery catheter (infusion tube) was attached to the applicator and covered with a disposable protective sheath. Prior to use, 2 mL of OvuGel was pre-loaded into the catheter by slowly compressing and releasing the applicator handle. This allowed displacement of any air from the infusion tube. The anterior end of the catheter and sheath were then inserted into the vagina at an upward angle of approximately 45°. Once resistance was felt indicating that the cervix had been reached, the catheter was retracted approximately 17 or 18 mm and 2 mL of OvuGel was deposited by squeezing the applicator. If urine excretion occurred, the catheter and sheath were removed and discarded to avoid potential contamination. After
Ziecik, A. J., A. Waclawik, M. M. Kaczmarek, A. Blitek, B. M. Jalali, and A. Andronowska. 2011. Mechanisms for the establishment of pregnancy in the pig. Reprod. Dom. Anim. 46: 31- 41. Appendix Tables Table A1. Effects of OvuGel® and P.G. 600® alone or in combination on reproduction in sows by treatment. P-values Item: TRT11 TRT21,2 TRT32 TRT4 SEM OvuGel vs. No OvuGel P.G. 600 vs. No P.G.600 P.G. 600 x OvuGel Number of sows 24 24 24 24 --- --- --- Estrus by day 7 post-weaning, % 92.1 96.8 79.5 84.9 0.1 0.03 0.95 0.35 Estrus by day 10 % 95.2a,b 99.4a 82.7b 95.2a,b 0.1 0.09 0.39 0.09 Wean-to-estrus, days 5.2 4.7 5.0 5.5 0.4 0.09 0.03 0.92
Live pigs/dose of semen 5.61 5.22 3.31 3.09 1.0 0.03 0.93 0.76 1Sows treated with OvuGel 96 h post-weaning 2Sows treated with P.G. 600 at weaning (h 0) Appendix Figures Figure A1. Wean to estrus interval among treatments. Sows in TRT2 and TRT3 received 5 mL of P.G. 600 (Merck Animal Health; De Sota, KS) at weaning (h 0) and sows in TRT1 and TRT2 received 2 mL of OvuGel (JBS United Animal Health; Sheridan, IN) 96 h post-wean. Data are represented as least-square means ± SE. There was a main treatment effect of P.G. 600 on WEI (P < 0.05) but no effect of OvuGel or P.G. 600 x OvuGel.