02131naa a2200229 a 450000100080000000500110000800800410001910000180006024501280007826000090020652014820021565000130169765000200171065000130173065000100174365000100175365000100176365000150177370000190178870000170180777300770182415211442023-04-27       1960    bl uuuu     u00u1 u    #d1 aCOOMBE, J. B.  aA study of milk production of the grazing ewe, with emphasis on the experimental technique employed.h[electronic resource]  c1960  aAbstract: Milk production was estimated in 11 Romney Marsh X Merino and 9 Border Leicester X Merino ewes which had each produced a single lamb and were grazing similar pastures. In one method yield was estimated weekly from one week after parturition; during a recording period of 30 h the lamb was allowed to suck every 5 h and was weighed before and after sucking. In the other oxytocin was used weekly on each ewe, 2 days after the sucking method. The ewe was milked by hand immediately after an injection of 5 I.U. oxytocin. After milking was completed a further 2.5 I.U. oxytocin was given and the ewe was milked out again. This complete procedure was repeated 2 h later while the lamb was kept away from the ewe. The yield obtained was taken as the milk secreted during 2 h, and from this production in 24 h was calculated. Lactation curves obtained by both methods were similar in shape; oxytocin gave a significantly greater estimated yield throughout. Yields of both crossbreeds were the same when estimated with oxytocin, and with lamb sucking the difference was not significant. There was a significant positive correlation between growth rate of lambs and milk yield estimated by either method in the first 4 and the next 3 weeks of lactation; from the 7th to the 10th week the correlation was not significant. Milk yield was not related to weight of the ewe at parturition or to birthweight of the lamb. The limitations of both methods are discussed.-J. G. Gordon.  aEwe milk  aMilk production  aOxytocin  aSheep  aLeite  aOvino  aProdução1 aWARDROP, T. D.1 aTRIBE, D. E.  tThe Journal of Agricultural Sciencegv. 54, n. 3, p. 353-359, Jun. 1960.