The influence of marternal handicap on growth and reproduction in sheep

Abstract

Ooie met enkel lammers het of voldoende vore ontvang om liggaamskondisie gedurende laktasie te handhaff (hoe peil) of die hoeveel-heid voer is verminder sodat n gemiddelde verlies van naastenby 20% in liggausmaan teweeggebring (lae peil). Die lammers het vrye toe-gang tot ru-en konsentraatvoere gehad. Na speen is die lammers gevoer om vinnige groei te bevorder. Die sogende lammers van ooie op die lae voedingspeil het nie merkbaar groter hoevoelhede ruvoer en konsentraat ingeneem as soortgelyke lammers van ooie op die hoe peil nie. Ondervoeding van die lakterende ooie het die ooi lammers by speen beduidend verlaag (P=0,001). Gedurende die naspeen tydperk is  hierdie agterstand in groei van die lammers geleidelik verminder, maar was nog merkbaar by geboorte van hul eerste lam.

SUMMARY

Ewes with single lambs received either sufficient feed to maintain body condition during (high plane) or the qunatity of feed was reduced so as to result in an average loss of approximately 20% in bodymass (low plane). The suckling lambs had free access to roughage and concentrate feeds. After weaning the lambs were fed so as to promote rapid growth. The lambs suckled ny ewes on the low plane did not consume appreciably greater quantities of roughage and concentrate than similar lambs reared by ewes which were adequately fed. Under-feeding of the lactating ewes significantly reduced the bodymass of their ewe-lambs at weaning (P=0,001). The deficit in growth of the lambs was gradually reduced during the post-weaning period, but was still evident in their first parturition.