03637naa a2200313 a 450000100080000000500110000800800410001902400460006010000190010624501370012526000090026250001640027152025920043565000150302765000290304265000110307165000200308265300080310265300140311065300180312465300180314265300340316070000150319470000170320970000120322670000170323870000240325577300440327910584722019-11-04       2018    bl uuuu     u00u1 u    #d7 a10.1016/j.theriogenology.2018.03.0212DOI1 aERRANDONEA, N.  aShort term protein supplementation during a long interval prostaglandin-based protocol for timed AI in sheep.h[electronic resource]  c2018  aArticle history: Article history:Received 14 November 2017//Received in revised form 23 February 2018//Accepted 14 March 2018// Available online 21 March 2018.  aAbstract: The aim of this study was to evaluate the reproductive impact of a short-term protein supplementation on a long interval prostaglandin-based protocol (two PG injections 15 d apart; PG15) for timed artificial insemination in sheep. During the breeding season, 437 multiparous Merino ewes grazing native pastures (forage allowance of 6 kg of dry matter/100 kg of live weight; crude protein: 10.8%, metabolic energy: 2.1 Mcal/kg of dry matter) were selected. Ewes were allocated, according to body condition score (3.2 ± 0.2) and body weight (40.6 ± 4.9 kg, mean ± SD), to a 2 × 2 factorial design: type of estrus ?spontaneous estrus (SE) or induced with PG15 (PG15)?, and supplementation (yes or no) before insemination (+FF; soybean meal at Days ?10 to ?3; crude protein: 51.9%, metabolic energy: 2.8 Mcal/kg of dry matter; average consumption 0.9% live weight/ewe/day of dry matter). All ewes were cervically artificial inseminated (Day ?2 to ?3 in SE ewes at estrus detection; Day 0 = timed artificial insemination in PG15 ewes). Ovulation rate on Day 7, non-return to service on Day 23, conception, fertility, prolificacy and fecundity on Day 60 were evaluated. Ovulation rate (1.17 ± 0.40 vs. 1.06 ± 0.25), non-return to service at Day 23 (81.7 vs. 64.2%), conception (78.8 vs. 61.5%), fertility (75.2 vs. 61.5%) and fecundity (0.77 vs. 0.62) were higher in ewes from SE than PG15 group (P < 0.05). However, no differences were observed in prolificacy (1.02 ± 0.16 vs. 1.01 ± 0,12) between groups (P > 0.05). Protein supplementation increased ovulation rate (1.30 ± 0.45 vs. 1.17 ± 0.40), prolificacy (1.18 ± 0.39 vs. 1.02 ± 0.16) and fecundity (0.94 vs. 0.77%; P < 0.05), but not non-return to service on Day 23 (83.8 vs. 81.7%), conception (82.9 vs. 78.8%) or fertility (79.1 vs. 75.2%; P > 0.05) in SE group. The supplement feed to PG15 ewes increased ovulation rate (1.35 ± 0.45 vs. 1.06 ± 0.25), prolificacy (1.25 ± 0.43 vs. 1.01 ± 0.12) and fecundity (0.79 vs. 0.62%; P < 0.05) to levels comparable to SE + FF ewes (P > 0.05). The magnitude of the increase in ovulation rate in PG15 was greater than in the SE group (27 vs. 11%; P < 0.05). However, non-return to service on Day 23 (65.1 vs. 64.2%), conception (63.3 vs 61.5%), and fertility rate (63.3 vs. 61.5%; P < 0.05) remained similar in PG15 supplemented or not supplemented ewes. In conclusion, a short-term protein supplementation before cervical time artificial insemination improved the reproductive performance of ewes synchronized with the PG15 protocol to levels comparable to the SE group  aFERTILIDAD  aINSEMINACIÓN ARTIFICIAL  aOVEJAS  aPROSTAGLANDINAS  aEWE  aFERTILITY  aFOCUS FEEDING  aPROSTAGLANDIN  aTIMED ARTIFICIAL INSEMINATION1 aFIERRO, S.1 aVIÑOLES, C.1 aGIL, J.1 aBANCHERO, G.1 aOLIVERA-MUZANTE, J.  tTheriogenologygv. 117, p. 34?39, 2018.