Techniques used to increase the rumen undegradable protein fraction in locally produced plant protein sources

Date
2022-12
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: With pressure directed towards South African farmers to fulfill the increasing mutton and lamb demand along with increasing commodity prices, the necessity presents itself to make use of more affordable, readily-available, locally produced plant protein sources to satisfy the animals’ nutritional demands. Due to protein being an important nutritional aspect of a ruminant’s ration it is of utmost importance to ensure optimal utilization of the protein source. Processing methods such as extrusion and formaldehyde treatment increase the amount of rumen undegradable protein (RUP), enabling the animal to achieve its optimal genetic potential. This is due to the possible increased protein available for absorption in the small intestines. With the Southern Cape and Swartland regions being large producers of lupin and canola, these high-quality plant proteins could potentially be used as replacement protein sources that are more affordable, relative to fishmeal and imported soybean meal. The need for lamb intensification systems and feedlot finishing also presents itself, in order for South Africa’s lamb and mutton operations to supply the growing population’s demand. Thus, both strategies of sheep production intensification and the utilization of protected, more affordable plant protein sources could potentially act as a possibility to increase the small ruminant sector’s annual revenue and optimize the farmers’ operational sustainability and profitability. The aim of the study was to determine the effect of extrusion (Trial 1) and formaldehyde treatment (Trial 2) on the rumen undegradable protein fraction of locally produced plant protein sources, canola oilcake meal (CM) and sweet lupins (SL). The effect of extrusion (Trial 1) was determined using 56 Meatmaster lambs (live weight ca 22.9 kg). Lambs were housed at the metabolism facilities at Elsenburg, where they were placed in individual paddocks each supplied with ad libitum feed and water. Each lamb was supplied with a specific concentrated feed, based on the treatment group allocated to them. The four treatment groups were canola oilcake meal control (CC), canola oilcake meal extruded (CE), sweet lupin control (LC) and sweet lupin extruded (LE). Lambs were randomly allocated to the respective groups, with each group consisting of 16 lambs (7 ewes and 9 rams per group). No significant interaction was present for protein source and extrusion processing. A feed conversion ratio of 4.62 versus 4.85 kg feed/kg weight gain was present in the study for the extruded diet versus the control diet. An average daily gain of 0.310 kg/day and 0.320 kg/day were obtained for the control diet relative to the extruded diet. Similarly, no effect of extrusion on daily feed intake was observed between CM and SL. The production performance of lambs that received either CM (17.4% inclusion level) or SL (26.6% inclusion level) did not differ significantly. An average fat score of 4 was achieved, with no effect of processing or protein source on the carcass fat thickness. However, SL were identified as an inexpensive locally produced plant protein source, in comparison to canola oilcake meal, which obtains similar performance parameters in lambs under feedlot conditions in this study. The effect of formaldehyde treatment (Trial 2) was determined by using six Dohne Merino wethers (live weight of ca 95 kg), already fitted with rumen cannulas, housed at Kromme Rhee Experimental Farm, in order to determine the in situ crude protein (CP) and dry matter (DM) degradability. Each animal was placed in its individual paddock. They were fed an ad libitum basal diet consisting of 50:50 wheat straw and lucerne hay. Canola oilcake meal (CM) and sweet lupin seed (SL) were treated with formaldehyde (40% w/v) at concentrations of 10g (F10) and 15g/kg CP (F15). The treatments entailed CM control (CMF0), CM treated with 10 g/kg CP formaldehyde (CMF10), CM treated with 15 g/kg CP formaldehyde (CMF15), SL control (SLF0), SL treated with 10 g/kg CP formaldehyde (SLF10) and SL treated with 15 g/kg CP formaldehyde (SLF15). Treatments were incubated in the rumen at time intervals of 0, 2, 4, 12, 36, 48, 72, and 96 hours. Formaldehyde significantly decreased the soluble fraction and lowered the rate of degradation of the potential degradable fraction at both concentrations. The DM effective degradation was significantly decreased at all outflow rates with the largest effect seen at 0.08/h. Both treatment concentrations decreased DM effective degradation by 16.1% and 20%, respectively. Formaldehyde treatment also significantly decreased the CP effective degradation (27.9% at F10 and 31.1% at F15) at all outflow rates, with the largest effect seen at 0.08/h. Overall, formaldehyde treatment effectively decreased DM and CP rumen degradation at all outflow rates of both CM and SL. Therefore, formaldehyde treatment could be used to increase the rumen undegradable protein fraction. Potential improvement in animal performance in terms of live weight gain, average daily gain, and feed conversion efficiency has to be done in production studies.
AFRIKAANSE OPSOMMING: Met druk wat op Suid-Afrikaanse boere gerig word om aan die toenemende skaap- en lamsvleis aanvraag te voldoen, tesame met die stygende kommoditeitspryse, ontstaan die noodsaaklikheid om van meer bekostigbare, relatief beskikbare, plaaslik geproduseerde plant proteϊene gebruik te maak. Omrede proteϊene ‘n belangrike voedingsaspek van ‘n herkouer se rantsoen is, is dit van uiterste belang om optimale benutting van die proteϊenbron te verseker. Prossesseringsmetodes soos ekstrusie en formaldehiedbehandeling, verhoog die hoeveelheid rumen onafbreekbare proteϊene (RUP) wat die dier in staat stel om sy optimale genetiese potensiaal te bereik, as gevolg van verhoogde proteϊen beskikbaarheid in die dunderm. Met die Suid Kaap en Swartland-streke as groot produsente van lupiene en kanola, kan hierdie hoë kwaliteit plant proteϊene moontlik gebruik word as alternatiewe proteϊen bronne wat meer bekostigbaar is relatief tot vismeel en ingevoerde sojaboon meel. Die behoefte aan intensiewe lamstelsels en voerkraal afronding doen hom voor, sodat Suid Afrika se lam en skaapvleis industrie in die groeiende bevolking se aanvraag voldoen. Dus kan beide strategieë van skaap produksie intensifisering en die gebruik van meer bekostigbare plant proteϊen bronne moontlik dien as strategie om die herkouers sektor se jaarlikse inkomste te verhoog en die produsent se bedryfsvolhoubaarheid en winsgewendheid te optimaliseer. Die objektief/mikpunt van die studie was om die effek van beide ekstrusie en formaldehiedbehandeling te bepaal, om die RUP te verhoog van plaaslik, geproduseerde plant proteien bronne, kanola oliekoek meel (CM) en soet lupiene (SL). Die effek van ekstrusie (Proef 1) is met behulp van Meatmaster lammers (lewenede massa ± 22.9kg) bepaal. Lammers is gehuisves by Elsenburg se metabolisme fasiliteite waar hulle in individuele hokke geplaas is, waar elkeen ad libitum voer en water voorsien is. Die vier behandelingsgroepe was kanola oliekoek kontrole (CC), kanola oliekoek geekstrueer (CE), soet lupien kontrole (LC) en soet lupien geekstrueer (LE). Lammers is ewekansig verdeel in behandelingsgroepe, met elke groep bestaande uit 16 lammers (7 ooie en 9 ramme). Geen betekenisvole interaksie was teenwoordig vir proteϊenbron of ekstrusie prosessering nie. ‘n Voeromsetverhouding van 4.62 in vergelyking met 4.85kg voer/kg gewigstoename was teenwoording in die studie vir die geekstrueerde voer teenoor die kontrole voer. Netso, is geen effek van ekstrusie op die daaglikse voerinname tussen CM en SL waargeneem nie. Produksie van lammers wat CM (17.4% insluitingsvlak) of SL (26.6% insluitingsvlak) ontvang het, het nie betekenisvol verskil nie. ‘n Gemiddelde karkas vetgradering van 4 is behaal, met geen effek van ekstrusie prosessering of proteϊenbron op die karkas vetdikte nie. Soet lupiene is egter geidentifiseer as ‘n goedkoper, plaaslik geproduseerde plant proteϊen bron, in vergelyking met kanola oliekoek meel, waar Meatmaster lammers soortgelyke produksie data onder voerkraal toestande verwerf het. Die effek van formaldehied behandeling (Proef 2) is in situ bepaal deur gebruik te maak van 6 Dohne Merino skape (lewende massa ± 95kg), reeds toegerus met rumen fistulas, gehuisves by Kromme Rhee Proef plaas om die degradering van ru-proteϊene en droëmaterial in die rumen te bepaal. Individuele hokke per skaap is gebruik gedurende die proef. ‘n Ad libitum dieët bestaande uit 50:50 koringstrooi en lusernhooi is gevoer. Kanola oliekoek meel (CM) en soet lupien saad (SL) is behandel met formaldehied (40% w/v) by konsentrasies van 10g/kg (F10) en 15g/kg CP (F15). Die behandelings bestaan uit kanola oliekoek meel kontrole (CMF0), kanola oliekoek meel behandel met 10g/kg CP formaldehied (CMF10), kanola oliekoek meel behandel met 15g/kg CP formaldehied (CMF15), soet lupien kontrole (SLF0), soet lupien behandel met 10g/kg CP formaldehied (SLF10) en soet lupien behandel met 15g/kg CP formaldehied (SLF15). Die behandelings was by 0 (kontrole), 2, 4, 12, 36, 48, 72 en 96 uur in die rumen geϊnkubeer. Formaldehied behandeling het die oplosbare fraksie en die tempo van degradasie van die potensiële afbreekbare fraksie, by beide behandelings konsentrasies verlaag. Die droëmateriaal (DM) is aansienlik verminder by alle uitvloei tempos met die grootste effek by 0.08/h. Beide behandelings konsentrasies het die DM effektiewe degradasie drasties verminder by alle uitvloei tempos, met die grootste effek teen 0.08/h (F10 verminder met 16.1% en F15 vermider met 20%). Formaldehied behandeling het ook die CP effektiewe degradasie by alle uitvloei tempos drasties verminder, met die grootste effek by 0.08/h (F10 verminder met 27.9% en F15 verminder met 31.1%). Dus kan formaldehied behandeling gebruik word om die rumen onafbreekbare proteϊen fraksie (RUP) te verhoog, wat lei tot die potensiële verbetering in diere prestasie in terme van lewende gewigstoename, gemiddelde daaglikse toename en voeromset doeltreffendheid.
Description
Thesis (MScAgric)--Stellenbosch University, 2022.
Keywords
Meatmaster lamb -- Feeding and feeds, Oil cake as feed, Sweet lupins as feed, Non-degradable protein, Plant proteins, Proteins in animal nutrition, Plant proteins as feed, UCTD
Citation