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

Abstract

Contents The objective was to compare embryo yield and quality in lactating dairy cows superovulated (SO) with varying amounts of gonadotropins and FSH:LH ratios and inseminated with SexedULTRA™ sex‐sorted semen. The SO treatments (n = 77) involved 3 protocols: groups F700 and F1000 were given total doses of 700 and 1,000 IU of Folltropin (FSH:LH ratio 49:1), respectively, whereas group F700P300 was given 700 IU of Folltropin + 300 IU of Pluset (FSH:LH ratio 1:1). Cows were artificially inseminated 3 times over a 10‐hr interval with frozen‐thawed SexedULTRA™ sex‐sorted semen (total of 10 × 106 sex‐sorted sperm), starting 18 hr after onset of oestrus, with embryos/ova recovered 7 d after oestrus. Total number of recovered structures and transferable embryos were lower (p < 0.05) in F700 (4.7 ± 3.0 and 1.9 ± 1.7, respectively; mean ± SD) compared to F1000 (8.1 ± 3.8 and 4.4 ± 2.6) and F700P300 (8.5 ± 6.4 and 4.5 ± 3.3). Percentage of cows ovulating >50% of follicles ≥0.8 cm in diameter was lower (p < 0.05) in F700 (35.5%) than in F1000 (82.4%) and F700P300 (73.1%). Percentage of unfertilized oocytes was higher (p < 0.05) in F700 (45.0% vs. 27.7% for F1000 and 29.0% for F700P300) whereas percentage of morulae was higher (p < 0.05) in F1000 (19.3% vs. 8.7% for F700 and 12.2% for F700P300). Embryo quality was similar among groups (p > 0.05). In conclusion, embryo production in lactating dairy cows was improved by increasing total dose of gonadotropins from 700 to 1,000 IU, with SexedULTRA™ sex‐sorted semen yielding satisfactory fertilization rates and embryo quality.

167 Ovarian response and embryo production of cows superstimulated with different FSH regimens and inseminated with conventional or sex-sorted spermatozoa

“…This new technology has already been used for in vitro embryo production (Gonzalez-Marin et al, 2017), for AI following estrus (Maicas et al, 2020) or FTAI in cattle (Lenz et al, 2017;Thomas et al, 2017Thomas et al, , 2019, as well as in small ruminants (González-Marín et al, 2021). In SOV, as far as we know, the only published study (Dell'Eva et al, 2019) inseminated lactating Holstein cows three times with straws of two million spermatozoa each, from three bulls, and produced 3.6 transferable embryos (49.6%), on average. Furthermore, the mean percentage of UFO was 33.9%, independent of treatments.…”

“…These modifications are implicated in better sperm parameters (Gonzalez- Marin et al, 2017) and fertility (Lenz et al, 2017; compared to the older sorting technology. Even though there are some studies showing the results achieved following fixed-time artificial insemination (FTAI; Thomas et al, 2019) or AI after estrus detection (Maicas et al, 2020), apparently only one recent study has described the use of SexedULTRA for embryo production of superstimulated cows (Dell'Eva et al, 2019).…”

​Spermatozoa Sorting Techniques for the Sex Pre-selection: A Review

“…This resulted in a comparable conception rate with the conventional semen. In 2017, ST genetics launched 4M Sexed ULTRA TM and is expected to become the new industry standard for sexed semen (Thomas et al, 2017;González-Marín et al, 2018;Vishwanath and Moreno, 2018;Dell'Eva et al, 2019). IVF using sorted semen showed high purity, repeatability and comparable rates of cleavage and blastocyst formation were observed between conventional and sorted semen (Puglisi et al, 2006;Xu et al, 2009;Carvalho et al, 2010;López et al, 2013).…”

Effect of a neurokinin 3 receptor-selective agonist administration on the embryos recovered from superovulated cows

“…In general, SOV treatment of cows is performed by gradual dosing with porcine follicle stimulating hormone (FSH) for 3-4 days [1][2][3][4]. Several studies have addressed issues such as non-ovulatory follicles and inconsistent quality of recovered embryos in SOV-treated cows [5][6][7], but effective methods have not yet been established. During SOV treatment, pulsatile luteinizing hormone (LH) secretion is suppressed in cows [8,9].…”