The mating behaviour and semen characteristics of Finnish Landrace and Scottish Blackface rams

Abstract

SUMMARYFour Finnish Landrace and four Scottish Blackface rams were exposed at 21-day intervals over a period of 19 months to two ovariectomized ewes, which had been induced to show oestrus. The behaviour of each ram was observed for 10 minutes with each ewe. Over the period of the experiment the Finnish Landrace rams consistently mounted the ewes more often than did the Blackfaces and in this respect in particular the reproductive behaviour of the males of these breeds was found to be positively correlated with that of the females of their breed.Initially, however, the Finnish Landrace rams mated more ewes than did the Blackfaces, but from the time that all rams became sexually active it was impossible to differentiate between the ability of the two groups of rams to mate the ewes presented to them. Semen collections from each ram were attempted by the use of an artificial vagina, again at three-weekly intervals. The motility, density and proportion of live sperm did not differ between the two groups of rams.The average number of mounts accredited to each ram during the test increased from around 5 in the summer to around 35 in the autumn.