Published online by Cambridge University Press: 27 March 2009
This paper describes the comparative semen characteristics (volume, motility, sperm density, number of sperms, percentage live and abnormal sperms) of Corriedale (exotic) and Marwari and Jaisalmeri (indigenous) rams during the summer and rainy seasons under the arid conditions of Jodhpur, in northwestern India. Except for sperm density, the semen of indigenous animals was superior to that of the Corriedale, although the differences recorded were not of a magnitude to cause the Corriedale sheep to be considered reproductively ineffective under hot arid conditions, if managed properly. The present findings do not conform to the earlier views of the prevalence of ‘summer sterility’ in Corriedale rams observed under hot humid conditions but there appears to be a negative relationship between semen quality and atmospheric humidity. The Corriedale sheep are recommended for improving the sheep sector in the desert areas of Rajasthan.