The low response in terms of transferable embryos to the multiple ovulation and embryo transfer (MOET) treatments in buffalo species has increased the interest of scientists versus the in vitro embryo production technique. Furthermore, the possibility of using oocytes from young animals reduces the generation interval and enhances genetic improvement by maternal lineage. The aim of this study is the evaluation of the ovarian response of peripuberal buffalo heifers to three different hormonal schedules. The trial was carried out on 20 buffalo heifers 640±116 days old and 364±33 kg of body weight. On day 0 heifers undergone clinical examination of genital tract by ultrasound and a progesterone releasing intravaginal device was inserted in all animals. On day 3 buffaloes were divided in three groups according to their age, body weight and follicular population on day 0 and 3. Heifers in Group A (n=7) received a 4-day decreasing dosage of an equal mixture of 500 I.U. of FSH and LH; Group B (n=7) was treated with a single i.m. administration of 2000 I.U. of PMSG; Group C (n=6) received the single i.m. injection of PMSG as Group B and a 2-day decreasing dosage of an equal mixture of 175 I.U. of FSH and LH starting on day 5. On day 0, 3, 5, 6 and 7 buffaloes undergone an ultrasound examination of ovaries by using a portable ultrasound unit with a 7.5 MhZ rectal probe. Follicles were classified in three categories according to their size: small (diameter < 3 mm); medium (3<diameter<6) and large (diameter> 6 mm). The number of all follicles and the number and the diameter of medium and large follicles were recorded each day. Data were analysed by a standard statistical analysis (SAS, GLM Procedures). All three hormonal treatments resulted a great number of follicles on day 7. Animals in Group C showed a higher number of medium and large follicles on day 7 compared to heifers of the other groups. Furthermore a higher number of total follicles were recorded in Group C compared to the others (P<0.05 vs Group A and P<0.01 vs Group B). Within each treatment a significant reduction of small follicles accompanied by an increase of large follicles was recorded when day 5 is compared with day 7. This phenomenon was present in all treatments but is more accentuated in Group C (P<0.08). It is possible to hypothise that the administration of FSH+LH on day 5 and 6 stimulated the recruitment and the growth of a higher number of small follicles resulting in higher number of medium and large follicles compared to the other two treatments. Further studies are needed in order to verify the quality and the developmental capability of the oocytes.
Follicular population in buffalo heifers after three different hormonal treatments / Neglia, Gianluca; Maschio, M.; Mazzi, M.; Allegrini, S.; Borghese, A.; Terzano, G. M.. - STAMPA. - (2005), pp. 224-225. (Intervento presentato al convegno III Congresso Nazionale sull’Allevamento del Bufalo e 1° International Symposium of Europe and Americas tenutosi a Capaccio – Paestum, Salerno, Italy nel October 12 – 15, 2005).
Follicular population in buffalo heifers after three different hormonal treatments.
NEGLIA, GIANLUCA;
2005
Abstract
The low response in terms of transferable embryos to the multiple ovulation and embryo transfer (MOET) treatments in buffalo species has increased the interest of scientists versus the in vitro embryo production technique. Furthermore, the possibility of using oocytes from young animals reduces the generation interval and enhances genetic improvement by maternal lineage. The aim of this study is the evaluation of the ovarian response of peripuberal buffalo heifers to three different hormonal schedules. The trial was carried out on 20 buffalo heifers 640±116 days old and 364±33 kg of body weight. On day 0 heifers undergone clinical examination of genital tract by ultrasound and a progesterone releasing intravaginal device was inserted in all animals. On day 3 buffaloes were divided in three groups according to their age, body weight and follicular population on day 0 and 3. Heifers in Group A (n=7) received a 4-day decreasing dosage of an equal mixture of 500 I.U. of FSH and LH; Group B (n=7) was treated with a single i.m. administration of 2000 I.U. of PMSG; Group C (n=6) received the single i.m. injection of PMSG as Group B and a 2-day decreasing dosage of an equal mixture of 175 I.U. of FSH and LH starting on day 5. On day 0, 3, 5, 6 and 7 buffaloes undergone an ultrasound examination of ovaries by using a portable ultrasound unit with a 7.5 MhZ rectal probe. Follicles were classified in three categories according to their size: small (diameter < 3 mm); medium (3I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
