8 research outputs found
Distracting laying hens with a 'toy': Does it work?
Intensively housed animals may become mutually destructive, with resulting detrimental effects on production. The use of a commercially available plastic device, intended to distract laying hens, was investigated and found not to have the claimed effect. The means to plan a future experiment are supplied. Intensief-behuisde diere kan onderling vernietigend wees, met nadelige gevolge vir produksie. Die gebruik van 'n kommersieel-beskikbare plastiese voorwerp wat lehenne se aandag aftrek is ondersoek. Daar is bevind dat die voorwerp nie die beweerde uitwerking het nie. Die middele om 'n toekomstige eksperirnent te heplan word verskaf
Between-flock genetic differences in 40 Merino studs
Breeding values of production traits, relative to a genetic control flock, were estimated for 40 registered Merino studs. Breeding values, expressed as a percentage deviation from the control flock, varied from -16.7 to 31.2 for body mass, --6.4 to 28.1 for clean fleece mass and -3.7 to 13.2 for fibre diameter. The results indicate that some studs differed genetically. The correlations between stud phenotypicmeans and estimated breeding values for production traits were very low and statistically significant only for crimps per 25 mm (0.512) and total fold score (0.424). Overall means, standarddeviations and correlationsfor the unselectedtwo-toothewe and ram progeny of the 40 studs, are presented.Teelwaardes vir produksiekenmerke,relatief tot 'n genetiese kontroletrop, is vir 40 geregistreerde Merinostoeterye bereken. Teelwaardes, uitgedruk as 'n persentasie afwykingvanaf die kontroletrop,het gevarieer vanaf -16.7 tot 31.2 vir liggaamsmassa,-6.4 tot 28.1 vir skoonwolmassaen -3.7 tot 13.2 vir veseldikte. Die resultate dui op genetiese verskille tussen sommige stoeterye. Die korrelasies tussen stoet fenotipiese gemiddelde en beraamde teelwaarde vir produksiekenmerkewas baie laag en statisties betekenisvol vir slegs kartels per 25 mm (0.512) en totale plooitelling (0.424). Algehele gemiddeldes, standaardafwykingsen korrelasies vir ongeselekteerde tweetand-ooie en -ramme van die 40 stoeterye,word gegee