Effect of lameness on follicular dynamics in postpartum anestrous crossbred cows.

Lameness affects the reproductive performance of cows.It is not clear whether follicular dynamics is involved.Ovarian ultrasonography was performed once daily in eight non -lame (N) and 11 lame (L) cows for a period of 30 days each.Recurrent follicular waves could be detected every 8.3 ± 0.4 and 7.6 ± 0.5 days, respectively, in the N and L cows.There were no appreciable differences in the day of selection (Day 2.3 ± 0.2 versus Day 2.8 ± 0.2), maximum diameters (8.9 ± 0.6 mm versus 9.2 ± 0.5 mm) and certain characteristics pertaining to growth, static and regression of the dominant follicles (DFs) in the N versus the L cows.The L cows, however, had a tendency to have a higher number (P<0.10) as well as treatment -by -day interaction (P<0.05) for the identifi ed (detectable for more than one consecutive day) and unidentifi ed (detectable for one day only) small follicles (>3≤5 mm).In conclusion, lameness did not affect the DFs that developed but failed to ovulate, but more the number of small follicles, both identifi ed and unidentifi ed, hints at some perturbance in the follicular characteristics of lame cows that needs to be addressed in the light of the mechanisms governing follicular dynamics.