| Autor: |
Leal DF; Department of Animal Reproduction, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil., Viana CHC; School of Veterinary Medicine, Pontifical Catholic University Minas, Poços de Caldas 37714-620, Brazil., Almond GW; Department of Population Health & Pathobiology, College of Veterinary Medicine, North Carolina State University (NCSU), Raleigh, NC 27607, USA., Monteiro MS; Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), São Paulo 05508-270, Brazil., Garbossa CAP; Department of Nutrition and Animal Production, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil., Carnevale RF; Department of Nutrition and Animal Production, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil., Muro BBD; Department of Nutrition and Animal Production, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil., Poor AP; Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), São Paulo 05508-270, Brazil., Pugliesi G; Department of Animal Reproduction, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil., Nichi M; Department of Animal Reproduction, School of Veterinary Medicine and Animal Sciences, University of São Paulo (USP), Pirassununga 13635-900, Brazil., Watanabe TTN; Department of Population Health & Pathobiology, College of Veterinary Medicine, North Carolina State University (NCSU), Raleigh, NC 27607, USA., Marques MG; Embrapa Suínos e Aves, Concórdia 89715-899, Brazil.; Postgraduate Program in Animal Production and Health, Instituto Federal Catarinense, Concórdia 89703-720, Brazil. |
| Abstrakt: |
In this study, we evaluated the effectiveness of using estrogen-induced prolonged luteal function followed by prostaglandin F2 alpha (PGF2α) treatment to synchronize estrus in gilts. On day12 of the estrus cycle (D0 = first day of standing estrus), 52 gilts were assigned at random to two experimental groups: non-treated gilts (CON, n = 22), serving as controls, and prolonged luteal function group (CYP, n = 30), receiving a single treatment with 10 mg of estradiol cypionate intramuscularly Starting on day 12, blood samples were collected for estradiol and progesterone assays. Estrus detection started on day 17. Gilts from the CON group were inseminated at the onset of natural estrus. On day 28 CYP gilts were treated with PGF2α to induce luteolysis and inseminated at the onset of estrus. Gilts were slaughtered 5 d after the last insemination. A single treatment with estradiol cypionate prolonged luteal function in 90% of treated gilts. The duration of the estrous cycle was longer (p < 0.0001) for CYP gilts compared to CON gilts. CYP gilts showed synchronized estrus 3.96 ± 0.19 d after induction of luteolysis. The conception rate was similar (p = 0.10) for CON and CYP gilts. No difference was observed in the embryo recovery rate (p = 0.18) and total number of embryos per female (p = 0.06). The percentage of unfertilized oocytes, fragmented embryos and viable embryos was similar among females from CON and CYP groups (p > 0.05). The treatment of gilts with a single application of 10 mg of estradiol cypionate on day 12 of the estrous cycle was effective in prolonging luteal function and treatment with PGF2α resulted in synchronized estrus. Additionally, the synchronization protocol had no deleterious effect on fertility and embryonic development. |
