Comparison between Day 0 and traditional protocols for estrus synchronization and multiple ovulation in crossbred hair sheep

Figures & data

Figure 1. Traditional protocol schematic, 14 days with CIDR^®, applications of PGF2α, superovulatory treatment with 240 mg of pFSH, divided into eight decreasing doses with 12 h intervals, 12 h after CIDR withdrawal, it was administered 8.4 mg of a GnRH.

Figure 2. Day 0 protocol schematic, 6 days with CIDR^®, applications of PGF2α, superovulatory treatment with 240 mg of pFSH, divided into eight decreasing doses with 12 h intervals, started 84 h after CIDR withdrawal, two times of 8.4 mg of GnRH. *transrectal ultrasound exam.

Table 1. Number of recovered structures, total number of embryos, transferable and freezable embryos (mean ± SEM), fertilization, transferable embryos and freezability rates of crossbred (Dorper vs. Santa Ines) ewes according to the hormonal protocol used (Traditional vs. Day 0).

	Traditional	Day 0
Number of superovulation	9 (81.81%)	11 (100%)
Number of recovered structures	2.90 ± 2.01	2.99 ± 1.97
Number of recovered embryos	1.72 ± 1.29	1.63 ± 1.20
Number of transferable embryo	1.63 ± 1.20	1.54 ± 1.11
Number of freezable embryos	1.63 ± 1.20	1.54 ± 1.11
Fertilization rate*	59.37 (19/32)	54.54 (18/33)
Rate of transferable embryos**	94.73 (18/19)	94.44 (17/18)
Freezability rate***	94.73 (18/19)	94.44 (17/18)

*Number of embryos/number of structures collected; **Number of embryos of grade I, II and III/number of embryos collected; ***Number of embryos of grade I and II/number of embryos collected. No difference between the treatments (P > 0.05).

Figure 3. Degree of quality of embryos produced in vivo from crossbred (Dorper × Santa Ines) ewes according to the hormonal protocol used (Traditional vs. Day 0). ^A,BDifferent letters between treatments and grades indicate significant difference (P < 0.05).