REPRODUCTION - Facultad de Ciencias Veterinarias

MATERIALS AND METHODS
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REPRODUCTION
Forty milking buffalo (> 40 days after parturition) were assigned into two Groups (GnoeCG, n=20 and GeCG, n=20)
according parity, days of parturition, body condition score, presence of dominant follicle and CL on Day -12 (D -12), D0
and D9 (device removal). All buffaloes received an intravaginal progesterone device (1.0 g P4; DIB ® ) plus 2.0mg of
estradiol benzoate intra-muscular (IM, RicBE ® ) at random stages of estrus cycle (D0). On D9, the DIB ® was removed and a
luteolytic dose of PGF 2 a was administered (0.150 mg d-cloprostenol, Preloban ® ). On this day, buffalo in GeCG received
400IU of eCG (Folligon ® ). After two days (D11), each buffalo received 10µg of GnRH (Conceptal ® ). Buffaloes were examined
by ultrasonography (Mindray DP2200Vet, 7,5MHz) on D -12, D0 and D9 to verify the ovary status, from D11 to D14
(12hs apart for 60 hours) to establish the moment of ovulation and on D16, D20 and D24 to measure the CL. All animals
were bled in order to measure P4 level (RIA) on D16, D20 and D24. Data were analyzed by ANOVA. Results are presented as
untransformed arithmetic means ± SEM.
RESULTS AND DISCUSSION
Results are shown in the table below.
We evaluate the cyclic activities by the CL presence. It was verified by ultrasonographyc examination effected on D-12,
D0 and D9 that approximately 50% of buffalo did’t has any CL. These females were considered in anestrous. According to
Baruselli et al. 2 , the eCG effect is more pronounced as much as the incidence of anestrous, which was verified by the
authors in Bos indicus.
An the present study, no differences were found between groups regarding to the maximum diameter of dominate follicle,
time and synchrony of ovulation, as that observed by Marques et al. 11 with cows, Baruselli et al. 3 with heifers and Porto
Filho et al. 14 with buffalo. These results were different to the study of Cavalieri et al. 7 , that observed synchrony of
ovulation in cows treated with P4+E2 and eCG.
There were no differences between GnoeCG and GeCG on ovulation rate. However, the ovulation rate was numerically
increased by eCG administration. In a previous investigation 3 , the employment of eCG increased the ovulation rate in
heifers treated with P4 device. The low ovulation rate observed on GnoeCG is in agreement with the results obtained from
buffalo in anestrous 1, 12, 16 . These authors didn’t use eCG associated to the ovulation synchronization protocol. Thus,
although it constitutes in numeric increase, the utilization of eCG could promote better ovulation rates. The ovulation
rates obtained by Singh et al. 15 with the utilization (58.3%) or not (33.3%) of eCG associated to P4 devices in buffalo
corroborates this hypothesis. Moreover, Singh et al. 17, 18 reported ovulation rates of 65% and 100% in buffalo that
received eCG. On these both experiments, the authors verified that, neither buffalo presented ovulation on the groups
without eCG.
Proceedings 9 th World Buffalo Congress