Comparison of semen characteristics in Romanov and Lori Bakhtiari rams

One of the important aims in animal breeding is using the advantages of bio diversity. Romanov sheep is Russian native breed and has prominent features, such as high percent of twinning. Lori-Bakhtiari breed is dual-purpose (meat and wool) in Iran. Regarding the governmental policies, confluence between these two breeds is on the agenda. The aim of this research is to study comparatively some of the sperm features of rams in both breeds in terms of concentration, motility, morphometry. Semen samples of Lori and Romanov rams were collected in husbandry research station known as Shuli in Chaharmahal Bakhtiari Province in Iran. In this experiment, sperm parameters in Romanov ram including large diameter, small diameter, perimeter and area of head, tail length, mid piece and end piece length were estimated as 9.16±0.37 m, 4.77±0.41 m, 24.47±0.97 m, 24.89±1.94 m2, 57.59±1.50 m, 15.40±1.20 m and 42.19±2.10 m, respectively. A significant difference was observed between the large diameter and head area of sperm, while the small diameter and perimeter of sperm were similar. Motility of type A in Romanov rams was significantly higher. The tail and mid piece of Romanov sperms was significantly taller than these parts in Lori’s rams. It seems that taller length of the mid piece and more mitochondria concentration are the causes of higher motility in Romanov spermatozoa.