Response of SA Mutton Merino ewes and their lambs to supplementation with enriched oat, barley or triticale grain on wheat stubble grazing

Abstract

Oat, barley or triticale grain, enriched by addition of nitrogen, minerals, and an ionophore, was fed for 90 days as supplement at a level of 500 g per head per day to SA Mutton Merino ewes during late pregnancy and lactation. Data from 125 pregnant ewes were used to investigate live mass change during late pregnancy and lactation, while wool production (derived from 10 x 10 cm midrib squares tattooed on the right side of the ewes)
was studied with 57 of these ewes. Data from 130 lambs, alive on the ewes at weaning, were used to determine the influence of supplementation on birth mass, weaning mass and preweaning growth rate. The ewes receiving supplement succeeded in maintaining a higher (P ≤ 0,05) average live mass during lactation than the unsupplemented control group. Ewes receiving enriched barley tended to have smaller losses of live mass than those supplemented with enriched triticale. Supplementation tended to increase greasy and clean wool production per unit skin area, but no significant deviations from the control group were found. The birth mass of lambs born from ewes fed the supplement, tended to be higher than in the control group. Lambs reared by ewes supplemented with enriched oats and triticale were heavier (P ≤ 0,05) at weaning, with faster (P ≤ 0,05) growth rates than control group lambs. A similar tendency was observed in lambs reared by ewes receiving enriched barley as supplement.

Hawer-, gars- of triticalegraan is met die byvoeging van stikstof, minerale en 'n ionofoor verryk, en vir 90 dae teen 500 g per ooi per dag aan SA Vleismerino-ooie tydens laatdragtigheid en laktasie as aanvulling gevoer. Data van 125 dragtige ooie is gebruik om liggaamsmassaverandering gedurende laatdragtigheid en laktasie te ondersoek, terwyl wolproduksie (verkry van 10 x 10cm-midribvierkante op die regtersy van ooie getatoeëer) met 57 ooie bestudeer is. Data van 130 lammers, lewend by die ooie by speen, is gebruik om die invloed van aanvulling op geboortemassa, speenmassa en voorspeense groeitoename te ondersoek. Ooie waaraan aanvulling voorsien is, het 'n hoër (P ≤ 0,05) liggaamsmassa tydens laktasie gehandhaaf as die onaangevulde
kontrolegroep, terwyl die groep wat verrykte gars ontvang het, geneig het om kleiner liggaamsmassaverliese te toon as die groep waaraan verrykte triticale voorsien is. Aanvulling het geneig om rou- en skoonwolproduksie per eenheid veloppervlakte te verbeter, maar geen betekenisvolle afwykings van die kontrolegroep is verkry nie. Die geboortemassa van lammers van ooie wat aangevul is, het geneig om hoër te wees as by lammers van die kontrolegroep. Lammers wat deur ooie wat verrykte hawer- en triticale-aanvullings gekry het grootgemaak is, was swaarder (P ≤ 0,05) by speen as kontrolegroeplammers, en het vinniger (P ≤ 0,05) voorspeense groeitoenames gehandhaaf. 'n Ooreenstemmende neiging is by lammers van die groep waaraan verrykte gars voorsien is, ondervind.

Keywords: Enriched small grains, lamb growth, stubble grazing,
supplementation.