However, based on the farrowing rate and the number of piglets born alive after the application of conventional artificial insemination within 2 days from semen collection/dilution, it was found that the medium-term diluents were more effective. With regard to morphology and chromatin integrity, the percentage of abnormal and fragmented spermatozoa increased on day 2 compared to day 1 for all of the extenders. The results showed reduced viability, higher values for most of the kinetics, and higher immotile spermatozoa from day 1 to day 2 in all extenders however, the long-term extender was superior compared to the other two on both days. Viability, motility, kinetic indicators, morphology and DNA fragmentation were estimated. The long-term extender was used for a short time, within 2 days from semen collection, with the aim to investigate a possible advantage over the others regarding laboratory or farm fertility indicators at the beginning of the preservation time. Stored and used semen was also laboratory assessed at insemination time, on days 1 and 2 after the collection (day 0). A part of extended semen was used for artificial insemination on the farm (30 sows/extender), while the remaining part was stored for three days (16–18 ☌). The present study compared the quality characteristics of boar semen diluted with three extenders of different proposed preservation times (short-term, medium-term and long-term). In conclusion, a two-step dilution in TRIS-egg yolk-glycerol extender containing Equex STM yields significantly improved post-thaw quality and longevity of AWD spermatozoa, making it suitable for sperm banking and artificial insemination initiatives. Poor quality samples yielded similar results, except for acrosome integrity, which declined for Protocol 2. Protocols did not differ in normal sperm morphology or DNA integrity. Acrosome integrity was higher for Protocol 2 throughout post-thaw incubation, with a decrease after 2 h for both protocols. Viability was higher for Protocol 2 throughout the 8 h of incubation, with a decrease after 6 h, compared to 4 h for Protocol 1. Motility dropped to nearly 0% after 2 h incubation for Protocol 1. For good quality samples, motility and sperm motility index persisted for up to 8 h for Protocol 2, and was higher between 2 and 6 h after thawing with a decrease from 4 h of incubation. Semen was collected by electroejaculation from n = 24 AWDs, of which eight ejaculates of sufficient quality (four good quality with initial sperm motility of 75.0 ± 4.4% and four poor quality showing rapid decrease in sperm motility to 3.3 ± 3.3% prior to freezing) were frozen. In this study, two canine freezing protocols were tested: Protocol 1: a one-step dilution in TRIS-20% egg yolk containing 8% glycerol and Protocol 2: a two-step dilution in TRIS-20% egg yolk containing a final extender concentration of 5% glycerol and 0.5% Equex STM, coupled with a TRIS-citrate-fructose thawing solution. Previous freezing attempts yielded nearly 0% motile sperm within 2 h of thawing. In conclusion, the most suitable concentration of Minitube Equex paste in the current protocol was 1.9% supplemented with 9.0% glycerol in TEY-based freezing extender III, based on the conformity between data from manual guides and the observed sperm motility characteristics results.Ĭonservation management of endangered African wild dogs (AWD Lycaon pictus) can benefit greatly from development of sperm freezing and artificial insemination. Moreover, after thawing at 1 h, LIN (linearity) in Group IV was higher than in Group II (P < 0.05), but did not differ from the other groups. In Group IV after thawing at 0 h, rapid velocity and the velocity curved line were significantly higher than in Groups II and III (P < 0.05) but did not differ from Group I. After freezing and thawing, sperm motility characteristics were evaluated by Sperm Class Analyzer® incubated at 37 ☌ for 0 (10 min), 1 and 2 h post-thawing. Groups II, III and IV were the experiment groups, and contained different concentrations of Minitube Equex paste (Group II: 1.5% Group III: 1.7% and Group IV: 1.9%) added to the freezing extender III. Group I was the control and included only 1.5% Nova Equex STM paste. Each ejaculate was aliquoted and cryopreserved in base freezing extender III as Tris-citrate egg yolk (TEY) extender plus 9.0% glycerol classified into four groups. Fifteen ejaculates from 12 mature boars were collected by the glove-hand method. The aim of the present study was to determine the optimal concentration of Minitube Equex paste (Minitube, Tiefenbach, Germany) for boar semen cryopreservation in comparison with Nova Equex STM paste (control). However, Equex paste produced by Nova Chemical Sales Inc. Equex paste is a non-permeating cryoprotective agent (CPA) that improved post-thaw survival of spermatozoa during boar semen cryopreservation.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |