Die effek van vroegspeen op groei en puberteit van Karakoellammers

Abstract

Ten einde die invloed van speenouderdom van Karakoellammers op groeitempo en die aanbreek van puberteit te bepaal is 80 lammers met geboorte ingedeel in 4 groepe en op 4; 6; 8 en 12 weke gespeen. Die eerste drie groepe is met hulle moeders in krale gehou waar hulle toegang tot kruipvoer in korrelvorm gekry het en na speen ad lib. toegang tot dieselfde voer plus 'n goeie lusernhooi gehad het. Diekontrole groep het saam met hulle moeders in klein kampies geloop waar die ooie en lammers voerkorrels op die veld ontvang het. Groeitempo, voerinname sowel as die tyd van eerste oestrus wat as puberteit geneem is, is genoteer. Die vroee speen van Karakoellammers het geen nadelige invloed op enige van die veranderlikes gehad nie. Lentelammers het egter 'n groter voerinname met 'n laer voeromset getoon terwyl puberteit ook in hulle geval vertraag was (P < 0,01). Daar is tot die gevolgtrekking gekom dat lammers op 6 weke ouderdom 6f selfs vroeer gespeen kan word mits aan die vereistes van kruipvoeding aanvanklik en 'n proteiimryke naspeen-voer voldoen kan word.

English Title: The effect of weaning age on growth and puberty of Karakul lambs

English Abstract

The effect of weaning age of Karakul lambs on growth rate and the onset of puberty was analysed for 80 lambs randomly allotted to 4 treatment groups. Lambs were weaned at 4; 6; 8 and 12 weeks of age with the rust three groups being creepfed prior to weaning in pens with their dams and after weaning the lambs received a high protein pelletted ration plus good quality lucerne hay ad lib. The fourth group (control) was kept with their dams on good grazing and the ewe plus lamb received supplementary feeding on the veld. Growth rate as well as feed intake was measured and ewe lambs were teased from 5 months of age and rust oestrus taken as the onset of puberty. Early weaning had no detrimental effect on either growth rate up to 6 months of age or the onset of puberty. However, spring-born lambs had a greater feed intake at a lower conversion ratio than autumn lambs and onset of puberty was highly significantly delayed (P < 0,01). It is concluded that Karakul lambs could be successfully weaned at 6 weeks of age or even sooner without any detrimental effects on production traits provided that the correct feeding regime is followed.