Shortening of Estrous Cycle in Pigs by the Repeated Administration of Prostaglandin F2^|^alpha; and their Reproductive Performance

Abstract

῍ ῌ ̮QQQΐ̰ * ΐ̯Ῐ̯῍ 2ῐ+* ΐ ῑQQ +ῒ ̯ ++ῐ+-ΐ ῑQQ ,ῒ ̯-ΐ ῍ ῲ̱Ύ῭̰̱̱Ὺ̱ F,a ̰̮῝QΰῘ῍ ̮QQ̳̯QQQ̲̯̮QQ̰QῌῘ῝ῌ QQ + ; QQ̯̮QQ̳̰Ὼῥ̱̱̱῎ΎQ̮ῧῢQQQ̯QQῐ̰̮ῠῠQQῐ ̰ῥ̮῍ PGF,a QΰQ +* ῍῍ QQQ +* ῍̰̳QῘ῝ῌ PGF,a QΰQ̯ῐ̯ῠ῍ Q̯̮Q QQΐ̰ * ΐ ῑDay*ῒ ̯Ῐ̯ 2ῐ+* ΐ̯-ΐ ῍ QQ 3 Q̯QQ / Q̯Q 0 ῍ PGF,a ῑῪ ῲ̱Ύ` +/ mgῌ-mlῌ QQ 3* mgῌ+2 mlῒ ̰QQQῒῑ̯QΰῘ῝ῌ QQQ̯ῠ῍ ῏ῤ̯̯̯̯QῩQ̲´̰QΰῘ῝ῌ PGF,a QΰQ̯̯Q̮Q Qΐῠ῍ Day+..,ΐ*.. ̯ QQQ ῑ+3./ΐ*.1ῒ ̯ῗ Ῐῡ ῑp*.*+ῒ ̯QQῗ̰῝ῌ PGF,a QΰQ̯QQῲ̱Ὺ̰ Ύ΅̱̱ ῑPῒ ̮QῠQΰQ +ῐ, ΐ̮ῨQQῘ῍ Day+, ̱Qῠ̯Q + ngῌml ̯QQ̯Qῶ Ῐ῝ῌ PGF,a Qΰ̯ῧῩῢ̮ῗ̰῝̮QQ̯Q̮̰QQῘ῝̯ῖ̰QQ̰ 3*῍ ̯῍ + ῍̯ ῤῙQQ̯῞῝ῌ , ῍ῠ Day/ ̯ ῞QQ̰Q̮ῨQ̯ Q̰Q̮̯̯ῦ̯̰QQ̰ Q῞῝Q̲῍ ̲QQῠΊ̰̰ +-Q῍ ++ Q̯῍ QQῘ῝̰̯QῠΊ̰̰ +, Q῍ 2 Q̯ ̰̯̮ῸΎ΅῎ῪῦQQ̯ῖῴ̯῞῝ῌ ̯̯̯ῐ 1 ῍̯Q̳ ῍ QQQ῍ QQQQῠ῍ Ί̰̰̯Q̯ ++/.+ΐ+., ΐ῍ +*.0ΐ+.3 ῍῍ +..ΐ*.-kg ̯ῘQQ̯QQ̯῞῝ῌ QQ , ; PGF,a QΰQ̳̰ Day++ῐ+-̯-ΐ ̯Ῐ῝̱ ῠ῍ QQ + ̯῏ῤ̯̯̯̯ Q῞῝ῌ ̳QῐῠQQ̯̮QQ̳̰ῺῥQQQ +* ῍̰ῥ̮῍ PGF,a QΰQ῍ QQQΊ̰ ̰ / ῍̯Ῐ῝ῌ Q̯̮QQQΐ̰ * ΐ̯Ῐ̯῍ PGF,a QΰQ̯̮Q Qΐῠ Day+0.. ΐ*.0 ̯῍ QQQ̯ Day+3.0ΐ*.0 ̯ῗ Ῐῡ ῑp*.*+ῒ ̯QQῗ̰῝ῌ PGF,a QΰQ̯ P ̮Qῠ῍ Qΰ Qῧΐ ῑDay+,ῒ ̮ῨQQῘ῍ Day+-̱Qῠ̯Q + ngῌml ̯QQ̯Qῶ Ῐ῝ῌ ΰ῝῍ PGF,a Qΰ̯ῧῩῢ̮ῗ̰῝̮QQ̯Q̮̰Q̮῍ Q῍QQῘ῝ῌ Ί̯̮QQ Qῠ῍ Q̳ ῍ QQQ῍ QQQQΊ̰̰̯Q̯ ++..0ΐ*.3 ΐ῍ 3.0ΐ,./ ῍῍ +.,ΐ*., kg ̯̮Ὶ̰ῦῘQQ̯QQ̯῞῝ῌ ῖ̰Ῠ̯ῖ̯̮Ῠ῍ ̲Q ̲̳̯̰ 2ῐ+-ΐ̯ ̯-ΐ ̯ + ΐ῝Ῡ 2 Q ̯ ̯ PGF,a ̰̮῝QΰῙ̰ῖ̯̯῍ ̲QῠQ̳̯QQῘ῍ PGF,a Qΰ̯ῧῩῢ̮ῗ̰῝̮Q ̯̮̮̯ῦQQ̯̮QQ̯̰ῖ̯̮Qῗ̰῝ῌ

Corpus luteum Regression Induced by Prostaglandin F2α in Microminipigs During the Normal Estrous Cycle

“…This finding is the same as those in previous reports using domestic pigs with multiple PGF 2α injection (35,36). Even though progesterone concentrations in domestic pigs gradually decreased following multiple PGF 2α treatment, progesterone levels increased again after treatment when the CL maintained their function within 24 h after the final PGF 2α treatment (36).…”

“…From previous reports in domestic pigs, at least 75 mg dinoprost (approximately 0.6 mg/kg/experimental period) during the experimental period may be needed to induce luteolysis during the early luteal phase of the estrous cycle with high efficiency. Plasma progesterone concentrations, a general index of CL condition (37), in microminipigs treated with 1.5 mg intra-vulva dinoprost injection on D0 to D2 reached baseline 3.7 days from the first treatment day, which is similar to previous reports (25,35,36). In our research, total treatment dose (4.5 mg dinoprost) per experimental period (approximately 0.3 mg/kg/experimental period) in microminipigs treated with intra-vulval administration of PGF 2α induced the decline of progesterone levels in the 1.5 PG group but not in the 0.75 PG group.…”

“…When female pigs were given 12.5 mg PGF 2α 12 times (25) or 15 mg PGF 2α six times intramuscularly (35,36) during the luteal phase of the estrous cycle, inter-estrous intervals in the treatment groups (13.3-15.7 days) were significantly shortened compared to the control groups (19.8-21.2 days). Our results are in accordance with these inter-estrous intervals (25,35,36), thereby demonstrating that the estrous length in cyclic microminipigs can indeed be controlled with the fewer injections than that needed in domestic pigs.…”