The fleece of the Scottish Blackface sheep. IV. The effects of pregnancy, lactation and nutrition on seasonal wool production

Abstract

Pre-mating, pregnancy and lactation periods correspond approximately with summer, winter and spring and any effects either of physiological status or nutritional conditions are confounded with the natural rhythm of wool growth. Within this framework, barren ewes produced slightly more wool than in-lamb ewes in winter and considerably more during the period of lactation. Improved nutrition during winter produced no increase in wool production, although it had a marked effect on live-weight maintenance. During lactation, improved nutrition resulted in an increase in wool production. The implications of the nutritional and seasonal rhythm of wool productions are discussed in relation to the adaptation of the breed to its environment.