title: Comparison of pregnancy rates with two estrus synchronization protocols in Italian Mediterranean Buffalo cows.
abstract: The aim in this study was to compare two estrus synchronization protocols in buffaloes. Animals were divided into two groups: Group A (n=111) received 100 microg GnRH on Day 0, 375 microg PGF(2alpha) on Day 7 and 100 microg GnRH on Day 9 (Ovsynch); Group B (n=117) received an intravaginal drug release device (PRID) containing 1.55 g progesterone and a capsule with 10mg estradiol benzoate for 10 days and were treated with a luteolytic dose of PGF(2alpha) and 1000 IU PMSG at the time of PRID withdrawal. Animals were inseminated twice 18 and 42 h after the second injection of GnRH (Group A) and 60 and 84 h after PGF(2alpha) and PMSG injections (Group B). Progesterone (P(4)) concentrations in milk samples collected 12 and 2 days before treatments were used to determine cyclic and non-cyclic buffaloes, and milk P(4) concentrations 10 days after Artificial insemination (AI) were used as an index of a functional corpus luteum. Cows were palpated per rectum at 40 and 90 days after AI to determine pregnancies. All previously non-cyclic animals in Group B had elevated P(4) (>120 pg/ml milk whey) on Day 10 after AI. Accordingly, a greater (P<0.01) relative percentage of animals with elevated P(4) 10 days after AI were observed in Group B (93.2%) than in Group A (81.1%). However, there was no difference in overall pregnancy rates between the two estrus synchronization protocols (Group A, 36.0%; Group B 28.2%). When only animals with elevated P(4) on Day 10 after AI were considered, pregnancy rate was higher (P<0.05) for animals in Group A (44.4%) than Group B (30.3%). The findings indicated that treatment with PRID can induce ovulation in non-cyclic buffalo cows. However, synchronization of estrus with Ovsynch resulted in a higher pregnancy rate compared with synchronization with PRID, particularly in cyclic buffalo.
authors.affiliation: Dipartimento di Scienze Zootecnichee Ispezione degli Alimenti (DISCIZIA), Faculty of Veterinary Medicine-Federico II University, Naples 80137, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Neglia
authors.forename: Bianca
authors.initials: B
authors.lastname: Gasparrini
authors.forename: Rossella
authors.initials: R
authors.lastname: Di Palo
authors.forename: Clemente
authors.initials: C
authors.lastname: De Rosa
authors.forename: Luigi
authors.initials: L
authors.lastname: Zicarelli
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Campanile
mesh_terms: D000818:Animals; D002020:Buffaloes / Q000502:physiology*; D015237:Dinoprost / Q000008:administration & dosage*; D004958:Estradiol / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D004973:Estrus Synchronization / Q000379:methods*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage*; D007315:Insemination, Artificial / Q000662:veterinary; D008297:Male; D008892:Milk / Q000737:chemistry; D011247:Pregnancy; D018873:Pregnancy Rate; D011374:Progesterone / Q000008:administration & dosage / Q000032:analysis
chemical_list: C074283:estradiol 3-benzoate; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D004958:Estradiol; D015237:Dinoprost