Follicular dynamics in superstimulated adult buffaloes.

The aim of this trial was to study the follicular dynamic in superovulated buffaloes. The trial was performed on 26 adult buffaloes synchronized by a double PGF2α injection 12 days apart. The day of estrus (Day 0) a progesterone releasing intravaginal device (PRID) was inserted and on day 7 the animals were divided in three homogeneous groups and assigned to one of the following treatments: 1) Group A (n=7) received a 4-days decreasing dose of an equal mixture of 1000 IU of FSH+LH; 2) Group B (n=9) was treated a single i.m. injection of 2000 IU of PMSG in a five days schedule; 3) Group C (n=10) received the same injection of PMSG and a 2-days decreasing dosage of 300 IU of FSH+LH, starting four days after PMSG. The PRID was removed the day before the end of the treatments in all groups and ultrasound examinations were performed daily starting on day 7 till the end of the treatments by a 7.5 MhZ linear rectal probe. Statistical analysis was carried out by GLM Procedures (SAS). Buffaloes in Group B showed a lower number (P<0.01) of large (6-10 mm) follicles compared to Group A and C (3.4 vs 10.2 and 9.1 respectively). Moreover a lower (P<0.05) number of very large follicles (>10 mm) was recorded in Group B vs A and C (1.4 vs 3.1 and 4.4 respectively). It is worth pointing out that a significant (P<0.05) decrease of small follicles was observed in Group C after FSH+LH administration (8.00 vs 4.3). In conclusion in Group C there is a further recruitment of small follicles during the treatment, increasing the number of large and very large follicles.