K. Musaddin, M. Y. Mohd Khusahry and I. Jasni

Abstract

A total of 49 15-month-old rams comprising Border Leicester x Malin (BM, n=6), Corriedale x Malin (CM, n=7), Dorset Horn x Malin (DM, n=10), Suffolk x Malin (SM, n=17) and Malin (n=9) were used in this study to evaluate their semen quality, scrotal circumference and libido status. The mean ejaculate volume of SM (0.67 mL) was highest (p <0.01) among the five breedtypes and this could be related to their large scrotal circumference of 29.14 cm as compared with the other breedtypes. The smaller-sized indigenous Malin rams which had smaller scrotal circumference and shorter testes, produced significantly lesser (p <0.01) semen volume. Sperm concentrations were similar among BM, CM,DM and SM rams, and the values were significantly higher (p <0.01) than that for Malin rams. No significant differences in the sperm mass motility, which ranged between 4.11 and 4.36, were observed in the semen of wool Malin crossbreds. Malin rams recorded the lowest (p <0.01) sperm mass motility. All rams had live spermatozoa greater than 95%. Total sperm abnormalities were lowest (p <0.05) in CM rams but highest in SM rams. The common types of abnormalities of spermatozoa observed were bent and off-centered mid-pieces. However, the abnormalities for all breedtypes in this study were lower than the minimum value of 25% required for satisfactory ram fertility. Based on these findings, the semen characteristics of the four wool Malin crossbred rams evaluated are of good quality and should be able to settle down (impregnate) ewes. No significant differences were observed in the time taken by the Malin and wool crossbred rams to achieve ejaculation, which varied between 23.45 s and 38.52 s. The five ram breedtypes had similar libido status. Based on this study, it can be concluded that the utilization of any of these breedtypes in natural mating programmes may yield acceptable success rates.

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