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The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals
Thesis (MScAgric)--Stellenbosch University, 2021.
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| Language: | English |
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Stellenbosch : Stellenbosch University
2021
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| _version_ | 1867613763073474560 |
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| access_status_str | Open Access |
| author | Skippers, Zarinah |
| author2 | Van Zyl, Johan Hendrik Combrink
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| author_browse | Skippers, Zarinah Van Zyl, Johan Hendrik Combrink |
| author_facet | Van Zyl, Johan Hendrik Combrink
Skippers, Zarinah |
| author_sort | Skippers, Zarinah |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MScAgric)--Stellenbosch University, 2021. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/109962 |
| institution | Stellenbosch University (South Africa) |
| language | English |
| last_indexed | 2026-06-10T12:41:18.607Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2021 |
| publishDateRange | 2021 |
| publishDateSort | 2021 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/109962 The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals Skippers, Zarinah Van Zyl, Johan Hendrik Combrink Cruywagen, C. W. Stellenbosch University. Faculty of AgriSciences. Dept. of Animal Sciences. Exogenous fibrolytic enzymes -- Feed utilization efficiency Enzymes in animal nutrition Ruminants -- Feeding and feeds Rumination (Digestion) Feed additives -- Physiological effect Neutral detergent fibre -- Techniques UCTD Thesis (MScAgric)--Stellenbosch University, 2021. ENGLISH ABSTRACT: Ruminants possess the ability to effectively utilise nutrients from fibrous plant matter and convert it into consumables for human use. However, digestion of plant cell walls is not complete as less than 65% of plant cell wall content is digested under optimal rumen conditions. As a result, ongoing research has been conducted on techniques for the improvement of fibre digestibility. Exogenous fibrolytic enzymes (EFE) has been proposed as a feed additive in order to improve fibre digestibility in ruminant production systems, with positive results. The feasibility of ABO374 as an EFE, with the potential to improve fibre digestibility in ruminant animals, was evaluated by means of a comparative study with commercial product, Rumenase®. Feed substrates, lucerne hay (LH) and wheat straw (WH), were treated with a control (dH2O) and the two EFE products. The treated feeds were left overnight before being evaluated for in vitro fibre degradation, and incubated for 0, 4, 8, 24, 48, 72, 96 and 120h. The rate and extent of dry matter (DM) and neutral detergent fibre (NDF) degradation of the treated feeds were then calculated. The results indicated improved NDF degradation of LH (P < 0.05) when compared to the control. An improvement greater than 29.9% was reported for WS fibre degradation. Despite a lack of significant difference between EFE treatments, the addition thereof improved fibre degradation, with LH most affected by ABO374 and WS most affected by Rumenase®. The supernatant ABO374 was deemed as effective as commercial product. In a second experiment, the effect of EFE pre-treatment incubation time (PIT) on fibre degradation was evaluated using three times (0.5, 3 and 12h) on three feeds (LH, WS, and total mixed ration or TMR). The enzyme-treated feed samples were evaluated by in vitro assessment inoculated with rumen fluid, as in the first experiment. Significant effects of DM degradation were reported for 0.5 and 3h PIT when compared to 12h (P = 0.03). Although the effects PIT on NDF degradation was not significant (P > 0.05), a tendency that favoured 0.5 and 3h treatment times over that of 12h was observed (P = 0.08), supporting the results of DM degradation. No significant differences were observed between 0.5 and 3h pre-treatment incubation times, and a 3h PIT was chosen as the preferred incubation time for practical application in ruminant production systems. On the basis of these results, an experiment was conducted to determine the probability of replicating ABO374 using pure enzymes, and the efficacy of the replicated enzyme cocktail in ruminant fibre degradation. Enzyme activity assays were performed to determine the ratio in which amylase, endoglucanase, mannanase and xylanase occurred in ABO374. This data was used to create the replicated synthetic cocktail. The two EFE products were compared to a control treatment to determine their effects on fibre degradation. An enzyme PIT of 3h was used on LH, WS and TMR feed substrates before assessing the ruminal in vitro degradation thereof at incubation 6, 12 and 24h). Enzyme treated WS exhibited the greatest improvement in DM degradation at in vitro 6 and 12h incubation times (P = 0.02 and P = 0.04, respectively). The NDF degradation of WS showed no differences between EFE treatments and the control, although tendencies in favour of enzyme treatment (P < 0.10) were reported. The addition of ABO374 resulted in improved NDF degradability in ruminant in vitro studies, although some inconsistencies did occur. These inconsistencies could be a result of insufficient enzyme activity, enzyme stability, poor enzyme-feed interactions or exogenous enzyme competition with rumen microbes. Despite the varied results, DM and NDF degradation was improved with the addition of EFE, pre-treatment incubation times was influential in fibre degradation, and a cocktail of enzymes increased the degradability of fibre in ruminant animals. Overall, the use of EFE has the potential to be an effective tool in the aim to improve the utilisation of forage and feeds in ruminant production systems. AFRIKAANSE OPSOMMING: Ruvoere vorm die hoofbron van vesel in herkouerdiëte en die opname daarvan kan gesondheid en produksie van die diere beïnvloed. Herkouers besit die vermoë om voedingstowwe uit veselagtige plantmateriaal effektief te benut en om te skakel in bruikbare produkte vir menslike gebruik. Die vertering van ruvoer is egter nie altyd volledig nie. Selfs onder normale optimale rumentoestande word minder as 65% van plantselwande verteer. As gevolg hiervan word tegnieke wat veselverteerbaarheid kan verbeter toenemend deur navorsing ondersoek. Positiewe navorsingsresultate met die gebruik van eksogene fibrolitiese ensieme (EFE) as ‘n behandelingsmetodestrategie om veselverteerbaarheid in herkouerproduksiestels te verbeter. Die uitvoerbaarheid van ABO374 as ‘n EFE produk met die potensiaal om veselverteerbaarheid by herkouerdiere te verbeter was geëvalueer aan die hand van ‘n vergelykende studie met ‘n kommersiële ensiemproduk, Rumenase®. Lusernhooi (LH) en koringstrooi (KS), is behandel met 'n kontrole in die vorm van gedistilleerde water (dH2O) en die twee EFE-produkte. Die behandelde voere was oornag gelaat voordat dit geëvalueer is vir in vitro NDF degradering, met inkubasietye van 0, 4, 8, 24, 48, 72 en 96h. Die tempo en omvang van droëmateriaal (DM) en neutraal bestande vesel (NBV) degradering op die behandelde voere is bepaal. ‘n Verhoging (P < 0.05) van NBV degradering met LH teenoor die kontrole is waargeneem. ‘n Verbetering (P < 0.05) van meer as 29,9% is vir die NBV degradering van EFE behandelde KS teenoor die kontrole bewerkstellig. Ten spyte van 'n gebrek aan ‘n betekenisvolle verskil, het die toevoeging van fibrolitiese ensieme die tempo van NBV degradering numeries verhoog. Met numeriese verbetering is lusernhooi die meeste deur ABO374 behandeling beïnvloed, terwyl WS die meeste deur Rumenase® behandeling beïnvloed is. Die ABO374 resultate was egter vergelykbaar met die van die kommersiële produk. In 'n tweede eksperiment was die effek van voorbehandelinginkubasietyd (VIT) op veselafbraak op drie tye (0.5, 3 en 12 uur) op drie substrate (LH, KS en TGR) geëvalueer. Die ensiembehandelde voersubstrate was geëvalueer deur in vitro-toetsing met vars rumenvloeistof. Betekenisvolle verbeteringe in DM degraderingsverhogings (P = 0.03) vir VIT 0.5 en 3 uur in vergelyking met 12 uur is waargeneem. Alhoewel die effek van VIT op NBV degradering nie betekenisvol was nie, is 'n neiging (P = 0.08) tot die verhoging van behandelingstye 0.5 en 3 uur bo dié van 12 uur waargeneem. Geen beduidende verskille is tussen 0.5 en 3 uur voorbehandelinginkubasietye waargeneem nie. Drie uur voorafbehandelingstyd is as die voorkeur VIT vir praktiese toepassing in herkouproduksiestelsels is derhalwe geslekteer. Op grond van hierdie resultate is 'n eksperiment om die waarskynlikheid te bepaal of ABO374 met suiwer ensieme gerepliseer kon word uitgevoer. Tweedens is die vermoë van hierdie gerepliseerde ensiem-mengsel teenoor ‘n kontrole en ABO374 om versnelde veselafbraak te bewerkstellig ondersoek. Ensiemaktiwiteit is bepaal en gebruik om die verhouding waarin amilase, endoglukonase, mannanase en xilanase in ABO374 voorkom te bepaal. Die data is gebruik om ‘n vergelykbare sintetiese mengsel te skep. Die twee EFE-produkte is vervolgens met 'n kontrole (dH2O) vergelyk. 'n Ensiem voorbehandelingsinkubasietyd (VIT) van 3 uur is op LH-, KS- en TGR-voersubstrate gebruik voordat ‘n ruminale in vitro degradering daarvan met inkubasietye van 6-, 12- en 24 uur uitgevoer is. Koringstrooi het die grootste verbetering in DM-degradering getoon wanneer dit met EFE behandel was tydens in vitro inkubasietye van 6 en 12 uur (P = 0.02 en P = 0.04, onderskeidelik). Neutraal bestande vesel degradering van behandelde KS het geen beduidende verskille tussen EFE bronne of die kontrole getoon nie. ‘n Neiging (P < 0.10) ten gunste van EFE-behandeling teenoor die kontrole is egter wel waargeneem. Alhoewel die behandeling van voersubstrate met ABO374 teenstrydighede gelewer het, het dit wel onder sekere omstandighede tot ‘n verbetering (P = 0.05) in in vitro veselverteerbaarheid gelei. Hierdie teenstrydighede kan toegeskryf word aan onvoldoende ensiemaktiwiteit, ensiemstabiliteit, swak ensiem-voer-interaksies of kompetisie tussen eksogene ensiem en rumenmikrobes. Ten spyte van die uiteenlopende resultate, het beide DM- en NBV-degradering verbeter met die toevoeging van EFE. Die studie het ook bevestig dat VIT wel NDF degradering beinvloed terwyl 'n mengsel van ensieme die verteerbaarheid van vesel by herkouers verhoog. Oor die algemeen kan die gebruik van EFE 'n effektiewe strategie wees ten einde meer effektiewe veselbenutting vir herkouers te weeg te bring. Masters 2021-03-04T06:47:42Z 2021-04-21T14:34:03Z 2021-03-04T06:47:42Z 2021-04-21T14:34:03Z 2021-03 Thesis http://hdl.handle.net/10019.1/109962 en Stellenbosch University xiii, 77 pages application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Exogenous fibrolytic enzymes -- Feed utilization efficiency Enzymes in animal nutrition Ruminants -- Feeding and feeds Rumination (Digestion) Feed additives -- Physiological effect Neutral detergent fibre -- Techniques UCTD Skippers, Zarinah The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals |
| title | The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals |
| title_full | The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals |
| title_fullStr | The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals |
| title_full_unstemmed | The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals |
| title_short | The effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals |
| title_sort | effect of exogenous fibrolytic enzymes on fibre digestion in ruminant animals |
| topic | Exogenous fibrolytic enzymes -- Feed utilization efficiency Enzymes in animal nutrition Ruminants -- Feeding and feeds Rumination (Digestion) Feed additives -- Physiological effect Neutral detergent fibre -- Techniques UCTD |
| url | http://hdl.handle.net/10019.1/109962 |
| work_keys_str_mv | AT skipperszarinah theeffectofexogenousfibrolyticenzymesonfibredigestioninruminantanimals AT skipperszarinah effectofexogenousfibrolyticenzymesonfibredigestioninruminantanimals |