Fertility Results after Vaginal Deposition of Frozen‐Thawed Buck Semen Diluted with Two Different Extenders Using One‐ or Two‐Step Procedures

Abstract

In two field trials (T1 and T2), the effect of two different extenders for buck semen was tested. Semen from six (T1) and seven (T2) bucks of the Norwegian Dairy Goat breed was diluted either in a milk-based extender containing egg yolk (M) or in a commercially available extender without egg yolk [Andromed(®) (A)]. Dilution in M was performed in a two-step procedure including centrifugation of the ejaculates and removal of the supernatant, while dilution in A was performed in one step. During the two trials (T1 and T2) 514 and 714, does, respectively, were artificially inseminated during natural oestrus, and the farmers performed the inseminations themselves after attending an artificial insemination (AI) training course. Vaginal insemination with 200 × 10(6) spermatozoa diluted in M resulted in a 25-day non-return rate (NRR) and kidding rate of 37.3% and 24.5%, respectively, while semen diluted in A resulted in 31.7% NRR and a kidding rate of 19.8% (T1). In T2, NRR and kidding rate for AI performed with semen diluted with M were 42.7% and 28.5%, respectively, while dilution in A gave 37.2% NRR and a kidding rate of 26.8%. There was no significant effect of extender in the two trials [T1:p=0.068 (NRR), p=0.148 (kidding rate), T2:p=0.096 (NRR), p=0.38 (kidding rate)], but farmer had a significant effect on the fertility parameters in both trials. In conclusion, the present studies may indicate that Andromed(®) is suitable for buck semen. However, more research is necessary to confirm the results and to improve the fertility of does after vaginal AI with frozen-thawed semen.

Introducing Soybean Oil in Semen Extenders of Awassi Rams

“…Moreover, [28] reported increase in spermatozoa mot ility in a co mmercial extender based on soybean in comparison with egg yolk -Tris based extender. Also, [29] revealed that there are no significant differences in fertilizat ion and conception rates between soybean extender (Andro med®) and egg yolk-milk based extender. There is no doubt that plant lecithin will substitute egg yolk and milk based extenders in near future due to the high performance of chilled and cryopreserv ed spermatozoa [30; 31; 32].…”

Effect of fumigation height and time on cryopreservation of ram semen

“…However, it was found in this study that the quality of post-thawed spermatozoa quality after fumigation at 2 cm was higher, which contrasts with the findings of previous research. This difference may be attributed to variances in spermatozoa resistance to freezing, which could be influenced by species or breeds, as well as variances in the composition of the diluent used and the pre-equilibration time 32 , 33 . Another study on human spermatozoa have shown that differences in the volume of straws can also affect semen freezing 34 .…”

Topical application of cervix with hyaluronan improves fertility in goats inseminated with frozen-thawed semen

“…In goat, commercially acceptable pregnancy rates (67.5%) have been reported in case of cervical AI with cooled diluted fresh semen [1,13,31,32], whereas with F-T semen these figures are much lower [33][34][35]. In Thailand, in small holdings, prenancy rate of 29-30% have been reported when goats were artifically inseminated using F-T semen [36].…”