Seminal plasma is intimately connected to sperm physiology and particularly in South American Camelids, has demonstrated to be involved in multiple physiological reproductive events. Different percentages of seminal plasma (0%, 10% and 50%) were added to thawed llama semen samples with the objective of evaluating the interaction with cryopreserved sperm over time (0, 1.5 and 3 hr at 37°C). A total of 20 ejaculates from five adult llama males (n = 5; r = 4) were evaluated. A significant decrease in sperm motility, membrane function and live sperm was observed in all thawed samples (0%, 10% and 50%) at 0 hr when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > .05), but a significant increase in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples versus raw semen. When evaluating thawed samples over time, a significant decrease of motility and membrane function was observed, while the percentages of total live sperm were preserved over the 3 hr of incubation in all final concentrations evaluated. To conclude, the addition of 10% or 50% of seminal plasma was incapable of preserving motility or membrane function of frozen‐thawed llama sperm during 3 hr of incubation.
Semen cryopreservation is not available for massive use in South American Camelids (SACs) due to the lack of an efficient protocol and the low pregnancy rates obtained with artificial insemination (AI). The use of a single cryoprotectant (CP) is commonly used in SACs frozen semen. The objective of the study was to evaluate the combined cryoprotective capacity of two permeable CPs at different stages of the cryopreservation protocol in llama semen. Sixteen ejaculates from 4 llama males were analysed, and sperm quality was assayed in raw semen, at 5°C, after equilibration of samples with the CPs and when samples were thawed. The following CPs and combination were used: 6% glycerol (GL), 6% dimethylformamide (DMF) and the combination of both CPs: 3% GL and 3% DMF. A Kruskal-Wallis test and an experimental factorial design, considering one factor with four levels (raw semen, 6% GL, 6% DMF and GL/DMF), were used. Total sperm motility and live sperm with intact acrosomes remained unchanged after equilibration of samples (p > .05). A significant decrease in the percentage of functional membrane, motile and live sperm with intact acrosomes was observed when samples were thawed (GL, DMF and GL/DMF). Nevertheless, the cryopreservation protocols used preserved sperm DNA quality; thus, sperm chromatin condensation and DNA fragmentation were unaffected (p > .05) when GL, DMF and GL/DMF were used. To conclude, no superiority was found between the use of a single or a combination of permeable cryoprotectants to freeze llama semen.
The use of non-commercial and commercial extenders for cooling alpaca sperm has already been reported, the latter showing certain advantages over the first. The Andromed® (AM) extender was created for use in ruminants and has also been tested in ejaculated and epididymal alpaca sperm. According to the manufacturer, this extender does not need the addition of egg yolk (EY); however, it is known that the addition of EY to some extenders improves the preservation of cooled sperm. The objective of this study therefore was to compare a non-commercial extender (Tris) with the addition of EY vs. the commercial extender AM with and without the addition of EY, for cooling alpaca sperm obtained from diverted deferent ducts. Fifteen pools of deferent duct sperm were formed using samples from two or three different males for each. Each sperm pool was evaluated and then divided into three aliquots that were diluted to a final concentration of 30 × 106 sperm ml-1 (0 h) with either: (1) Tris with 20% EY (T-EY), (2) AM, or (3) AM with 20% EY (AM-EY). Samples were cooled to 5°C and the following sperm parameters were evaluated after 24 and 48 h of storage: motility, viability, membrane function, acrosome integrity, morphology, and chromatin condensation. Motility was also evaluated after 72 h of storage. The samples that best preserved progressive and total sperm motility at the 24 and 48 h evaluation periods were the ones diluted with AM-EY, observing that with this extender these motility patterns decreased significantly after 72 h of storage compared to time 0 h (p < 0.05). A significant decrease (p < 0.05) in total and progressive motility was observed at 48 h for the T-EY and AM extender compared to 0 h. AM was the only extender in which the percentages of viable sperm decreased significantly (p < 0.05) after 48 h of conservation. For the rest of sperm parameters evaluated, no significant differences were observed between any of the extenders at any evaluation time. The Andromed® extender with the addition of 20% EY could be an alternative option for cooling alpaca sperm obtained from deferent ducts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.