Fertilization rate and embryo production of superovulated dairy cows after insemination with non-sorted and sex-sorted semen

Abstract

The aim of this study was to evaluate the fertilization rate of cows that were superovulated and artificially inseminated with sex-sorted semen. Cows were treated with an intravaginal progesterone device plus estradiol benzoate (day 0). Superstimulation treatments began four days after with eight applications of FSH at 12 h intervals. D-Cloprostenol was administered on day 6. Progesterone device was removed on day 7, and LH was administered on day 8. The treatments were divided as follows: NonSx, two AI with non-sorted semen were conducted 12 and 24 h after LH; Sx12&24, two AI with sex-sorted semen were conducted 12 and 24 h after LH; and Sx24&36, two AI with sex-sorted semen were conducted 24 and 36 h after LH. Embryos were recovered on day 16 and were evaluated and classified. Percentage of fertilized embryos tended to be greater for the non-sorted semen than the sex-sorted semen. The number of unfertilized oocytes was smaller when the non-sorted semen was used relative to the sex-sorted semen. There was no difference between the treatments that used sexed semen. In conclusion, the use of sex-sorted semen in superovulated dairy cows results in greater numbers of unfertilized oocytes than non-sorted. However, when only sorted semen is used AI should be performed 24 and 36 h after LH.

Superovulation protocols for dairy cows bred with SexedULTRA™ sex‐sorted semen

“…In superovulated cows, SexedULTRA™ sex‐sorted semen yielded acceptable results (average of 4.5 embryos per flush), which seemed better than most studies involving traditional XY sex‐sorted semen in superovulated lactating dairy cows (3.1 embryos Schenk, Suh, & Seidel, ; 2.4 embryos Hayawaka et al ; 2.1 embryos Peippo et al, ; and 2.4 embryos Monteiro et al, ).…”

“…Reduced fertilization with sexed semen may be due to low doses of sperm, an abnormal uterine environment or atypical sperm transport in superovulated cows, damage to sperm during sex sorting, or some combination. Superovulated cows inseminated with sex‐sorted semen produced a significantly smaller proportion of transferable embryos and significantly larger proportions of unfertilized oocytes and/or degenerate embryos than heifers or cows inseminated with unsorted semen (Mikkola & Taponen ; Monteiro et al, ; Peippo et al, ). With 4M SexedULTRA™ sex‐sorted semen, fertility rates between conventional semen and sex‐sorted semen in single‐ovulating heifers approached equivalence (Vishwanath & Moreno, ); however, no data have been published regarding superovulated cattle.…”

Evaluación de un protocolo simplificado de superovulación en vacas Holstein en producción con semen sexado y convencional

“…La reducción de FSHp en el tratamiento es 77 Argudo et al otro importante beneficio ya que la eCG es menos costosa. En el tratamiento FSHp + eCG, no se obtuvieron ovocitos sin fertilizar, este es un resultado prometedor ya que el principal problema cuando se usa semen sexado es que existe una mayor proporción de ovocitos no fertilizados (Monteiro et al, 2016).…”