مقایسه خصوصیات مورفولوژی امواج فولیکولی در چرخه فحلی طبیعی با یک برنامه همزمانی در گاوهای شیری هلشتاین

The objective of the present study is to investigate the morphological characteristics of follicular wave in synchronized cycle in compare to the normal estrous cycle in dairy cattle. ten holstein dairy cows were randomly selected from the university of tehran dairy herd and assigned in 2 groups (n=5). the animals in treatment group were synchronized with 2 intramuscular injections of prostaglandin f2? 14 days apart. ovarian ultrasonography (b mode; pie medical, falco 100, 8 mhz) was done daily in control group between 2 consequently estrus and in treatment group after first pg injection until estrus following second pg injection. the data analyzed using sas. t-test was used to investigate the statistical difference between morphological characteristics of follicular wave. the result showed that there were no significant differences between the size of dominant follicle (f1), the largest subordinate follicle (f2), mean large size of subordinate follicles, mean size of f1(mm) at deviation, mean number of days from emergence of the follicular wave to deviation, mean number of follicles in the waves, mean age of follicles, day of emergence of the follicular wave, age of dominant follicle in synchronized cycle and normal estrous cycle (p > 0.05). in conclusion, the results showed that there were not significant differences between morphological characteristics of follicular wave in normal estrous cycle versus synchronized cycle.