Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa
Thesis (MScAgric)--Stellenbosch University, 2023.
Saved in:
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | English |
| Published: |
Stellenbosch : Stellenbosch University
2023
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867614032191553536 |
|---|---|
| access_status_str | Open Access |
| author | Van Niekerk, Liane |
| author2 | Lambrechts, Helet |
| author_browse | Lambrechts, Helet Van Niekerk, Liane |
| author_facet | Lambrechts, Helet Van Niekerk, Liane |
| author_sort | Van Niekerk, Liane |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MScAgric)--Stellenbosch University, 2023. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/128358 |
| institution | Stellenbosch University (South Africa) |
| language | English |
| last_indexed | 2026-06-10T12:45:35.384Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2023 |
| publishDateRange | 2023 |
| publishDateSort | 2023 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/128358 The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa Van Niekerk, Liane Lambrechts, Helet Olivier, Willem Johannes Stellenbosch University. Faculty of AgriSciences. Dept. of Animal Sciences. Sheep -- Breeding -- South Africa Spermatozoa -- Physiology -- Analysis Rams -- Reproduction -- Nutritional aspects Rams -- Physiology -- Climatic factors Trehalose Namaqua-Afrikaner -- Feeding and feeds UCTD Thesis (MScAgric)--Stellenbosch University, 2023. ENGLISH ABSTRACT: The Namaqua-Afrikaner (NA) is an indigenous South African sheep breed that is uniquely adapted to the harsh climates in the more arid regions of South Africa. The NA possesses desirable traits such as a good mothering ability and an ability to wean heavy lambs even in severe drought conditions, which makes it a desirable breed for crossbreeding programs. In an effort to preserve genetic material of the NA breed, which is considered to be endangered by the FAO, the Grootfontein Agricultural Development Institute Biobank was established in 2008. To date, efforts to build up a genetic resource for the NA breed were only successful in terms of embryos. No success has however been achieved to cryopreserve NA spermatozoa for the GADI Biobank. Little information is available regarding the pre-cryopreservation handling and processing of NA sperm samples. The study therefore investigated the effect of duration of equilibration, and final sperm concentration (300 million or 600 million spermatozoa per mL, respectively) on the survivability and morphology of NA spermatozoa during liquid storage at 4°C. In addition, the diluent was also supplemented with trehalose at either 0mM, 50mM or 75mM, to determine the potential of trehalose to minimise the changes induced by processing and storage. Sperm samples were collected from habituated and non-habituated rams by using the artificial vagina (AV) and electro-ejaculation (EE methods, respectively. The rams also differed in terms of age. All sperm samples were subjected to macro- and microscopic evaluation prior to and during liquid storage for up to 48h, at time intervals 0h, 6h, 12h, 24h and 48h, respectively. Diluted samples were equilibrated for up yo 5h, and sperm viability and morphology were recorded at 0h, 1h, 2h, 3h, 4h, and 5h, respectively. Degree of habituation did not influence either sperm morphology or -viability during liquid storage. Ram age tended to influence sperm tail morphology during liquid storage. The method of semen collection and final sperm concentration had no effect on sperm viability or -morphology. However, when the interaction between duration of equilibration and collection method was considered, sperm samples collected using the AV method were more resilient to the effects of slow cooling during equilibration. In cases where sperm samples need to be diluted for biobanking purposes, an end concentration of either 300 x 106 sperm/mL or 600 x 106 sperm/mL can be used. An equilibration period of 1 hour yielded the best sperm viability and -morphology values during this study. Trehalose supplementation minimised the changes induced by liquid storage by maintaining sperm viability and -morphology after storage at 4°C for up to 48h. Despite the fact that AV-collected samples were characterized by a higher overall survivability after 48h of liquid storage, AV-collected spermatozoa were more susceptible to morphological changes induced by cold storage, when compared to the EE-collected spermatozoa. Trehalose at an inclusion level of 50mM and 75mM, had a positive effect on sperm morphology, most predominantly in protecting the sperm tail region from morphological damages during liquid storage for up to 48h. In conclusion, for future crossbreeding and conservation programs, NA rams do not require habituation to facilitate the collection of sperm samples for biobanking purposes. Sperm samples can be collected using either the AV or EE method, with the former method that will produce samples that are biologically more representative than EE-collected samples. It is recommended that trehalose is included in storage media to minimise the changes induced by short-term (in liquid form) or long-term (cryopreserved) storage, to ensure that NA sperm samples remain viable for use in artificial insemination or for in vitro embryo production programs. AFRIKAANSE OPSOMMING: Die Namakwa-Afrikaner (NA) is 'n inheemse Suid-Afrikaanse skaapras wat uniek aangepas is vir die strawwe klimaat in die meer droë streke van Suid-Afrika. Die NA beskik oor wenslike eienskappe soos 'n goeie moedervermoë en 'n vermoë om swaar lammers te speen selfs in erge droogtetoestande, wat dit 'n wenslike ras vir kruisteelprogramme maak. In 'n poging om genetiese materiaal van die NA ras, wat deur die FAO as bedreig beskou word, te bewaar, is die Grootfontein Landbou-ontwikkelingsinstituut Biobank in 2008 gestig. Pogings om 'n genetiese hulpbron vir die NA ras op te bou was tot op hede, net suksesvol in terme van NA embrio's. Geen sukses is egter behaal om NA sperme vir die GADI Biobank te bevries vir langtermyn berging nie. Min inligting is beskikbaar rakende die voor-bevriesing hantering en verwerking van NA sperm monsters. Die studie het dus die effek van lengte van ekwilibrasieperiode en finale spermkonsentrasie (onderskeidelik 300 miljoen of 600 miljoen sperme per mL) op die oorlewing en morfologie van NA sperme tydens berging by 4°C ondersoek. Daarbenewens is die verdunningsmiddel ook aangevul met trehalose by óf 0mM, 50mM of 75mM, om die potensiaal van trehalose te bepaal om die veranderinge wat deur verwerking en berging veroorsaak word, te minimaliseer. Sperm monsters is van ramme wat nie gereeld aan menslike teenwoordigheid blootgestel is nie, en ramme wat daagliks aan menslike teenwoordigheid blootgestel is, versamel deur middel van die kunsmatige vagina (AV) en elektro-ejakulasie (EE metodes, onderskeidelik. Die ramme het ook verskil in terme van ouderdom. Alle spermmonsters is voor berging makroskopies evalueer, met mikroskopiese sperm lewensvatbaarheid en -morfologie wat gevolglik op die tydintervalle 0h, 6h, 12h, 24h en 48h, onderskeidelik, aangeteken is. Verdunde monsters is vir tot 5 uur ekwilibreer, met sperm lewensvatbaarheid en -morfologie wat op onderskeidelik 0h, 1h, 2h, 3h, 4h, en 5h van ekwilibrasie, aangeteken is. Die mate waartoe ramme aan menslike teenwoordigheid gewoond was, het nie óf spermmorfologie óf -lewensvatbaarheid tydens berging van sperm monsters by 4°C beïnvloed nie. Ram-ouderdom was geneig om spermstert morfologie tydens berging by 4°C te beïnvloed. Die metode van versameling van sperm monsters en finale spermkonsentrasie het geen effek op sperm lewensvatbaarheid of -morfologie gehad nie. Wanneer die interaksie tussen lengte van ekwilibrasie en versamelingsmetode egter oorweeg is, was sperme wat met die AV-metode versamel is, meer bestand teen die effekte van stadige afkoeling tydens ekwilibrasie. In gevalle waar sperm monsters vir biobank doeleindes verdun moet word, kan 'n eindkonsentrasie van óf 300 x 106 sperm/mL óf 600 x 106 sperm/mL gebruik word. 'n Ekwilibrasie periode van een uur het die beste sperm lewensvatbaarheid en -morfologie waardes tydens hierdie studie opgelewer. Trehalose-aanvulling het die veranderinge wat deur berging by 4°C veroorsaak word, tot die minimum beperk deur sperm lewensvatbaarheid en -morfologie te handhaaf vir tot 48 uur. Ten spyte van die feit dat AV-versamelde monsters gekenmerk is deur 'n hoër algehele oorlewingsvermoë na 48 uur van berging by 4°C, was AV-versamelde sperme meer vatbaar vir morfologiese veranderinge, in vergelyking met die EE-versamelde sperme. Trehalose by 'n insluitingsvlak van 50mM en 75mM het 'n positiewe effek op spermmorfologie gehad, hoofsaaklik in die beskerming van die spermstertstreek teen morfologiese skade tydens berging by 4°C vir tot 48h. Ten slotte, vir toekomstige kruisteling- en bewaringsprogramme, is dit nie nodig om NA ramme aan menslike teenwoordigheid gewoond te maak om hulle opleiding vir die versameling van sperm monsters vir biobankdoeleindes te vergemaklik nie. Spermmonsters kan met óf die AV- óf EE-metode versamel word, met eersgenoemde metode wat monsters sal produseer wat biologies meer verteenwoordigend is as EE-versamelde monsters. Dit word aanbeveel dat trehalose by bergingsmedia ingesluit word om die veranderinge wat deur kort-termyn (in vloeistofvorm) of langtermyn (diep bevriesing) berging veroorsaak word te minimaliseer, om te verseker dat NA spermmonsters lewensvatbaar bly vir gebruik in kunsmatige inseminasie of vir in vitro embrio produksieprogramme. Masters 2023-03-07T12:56:34Z 2023-08-30T13:14:17Z 2023-03-28 2023-03-07T12:56:34Z 2023-08-31T09:18:28Z 2023-03-07T12:56:34Z 2023-08-31T09:18:28Z 2023-03 Thesis https://scholar.sun.ac.za/handle/10019.1/128358 en Stellenbosch University application/pdf x, 103 pages : illustrations application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Sheep -- Breeding -- South Africa Spermatozoa -- Physiology -- Analysis Rams -- Reproduction -- Nutritional aspects Rams -- Physiology -- Climatic factors Trehalose Namaqua-Afrikaner -- Feeding and feeds UCTD Van Niekerk, Liane The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa |
| title | The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa |
| title_full | The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa |
| title_fullStr | The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa |
| title_full_unstemmed | The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa |
| title_short | The influence of duration of equilibration, final sperm concentration, and trehalose supplementation on sperm characteristics of Namaqua-Afrikaner spermatozoa |
| title_sort | influence of duration of equilibration final sperm concentration and trehalose supplementation on sperm characteristics of namaqua afrikaner spermatozoa |
| topic | Sheep -- Breeding -- South Africa Spermatozoa -- Physiology -- Analysis Rams -- Reproduction -- Nutritional aspects Rams -- Physiology -- Climatic factors Trehalose Namaqua-Afrikaner -- Feeding and feeds UCTD |
| url | https://scholar.sun.ac.za/handle/10019.1/128358 |
| work_keys_str_mv | AT vanniekerkliane theinfluenceofdurationofequilibrationfinalspermconcentrationandtrehalosesupplementationonspermcharacteristicsofnamaquaafrikanerspermatozoa AT vanniekerkliane influenceofdurationofequilibrationfinalspermconcentrationandtrehalosesupplementationonspermcharacteristicsofnamaquaafrikanerspermatozoa |