THE PHILIPPINE WATER BUFFALO

surgical transfer of an expanded blastocysts confirmed
this claim.
Keywords: embryo transfer, water buffalo
*Jpn. J. Vet. Res. 1989. 37:167-180. Also in Annotated
Bibliography on Philippine Biodiversity: Livestock and
Poultry (Agrobiodiversity) 1949-1997, Carabaos. 2002. p.
261.
R-45
SURVIVABILITY AND FERTILIZABILITY OF SWAMP
BUFFALO OOCYTES AFTER CRYOPRESER-
VATION*
M. B. Ocampo, Supervising Science Research Specialist, PCC-CLSU, DA
R. P. Soriano,
F. V. Mamuad, Center Director, PCC-CLSU, DA
Y. C. Lapid,
C. S. Lorenzo,
L. C. Ocampo, Senior Science Research Specialist, PCC-CLSU, DA
In this study, the ability of oocytes at germinal vesicle
(GV)-stage and M 2 stage to survive, mature and fertilize
after a freeze-warm using ethylene glycol (EG) was
investigated. Problems associated with the
cryopreservation of oocytes were also determined. Ovaries
were collected from local abattoir within two hour after
slaughter of the animals. Ocytes were aspirated from
antral follicles. Only oocytes surrounded by multilayered
compact cumulus cells (COCs) were selected before
allocating for treatments. In Expt. 1, immature oocytes
were exposed to VS A at either 1,3,5 and 10 min before
transferring to VS B for 45 sec, then plunged directly into
LN 2 . In Expt. 2, immature oocytes were cultured in vitro
to mature before exposing to VS A , VS B and LN 2 as in
experiment 1. No significant differences were observed
on the survivability of vitrified warmed GV stage oocytes
and on the capactiy of cumulus cells for expansion. Among
treatment groups, the meiotic resumption and the subsequent
completion of the 1 st meiosis was highest in oocytes
exposed to VSA for 5 min. Subsequent fertilization and
MPN formation rate was lower vs the control. Among
treatment groups, the fertilization rate was for oocytes
exposed for 5 min and 10 min but likewise showed higher
polyspermic fertilization. Oocytes exposed for 10 min had
the highest MPN formation rate in all experimental series.
The high percentage of morphologically normal oocytes
post-warming could be associated to the presence of the
cumulus cells. The hyaluronic acid matrix of the cumulus
cells may have provided a cryoprotective effect as it
appeared unperturbed by freezing (Schroeder et al, 1940).
This was further supported by the expansion capabilities of
the cumulus cells post-warming as observed in this study.
80
ABSTRACT OF RESEARCHES ON
THE PHILIPPINE WATER BUFFALO
Overall, the fertilization and MPN formation rate of vitrifiedwarmed
immature oocytes was lowered compared to
mature oocytes. Abnormal spindle formation and dispersion
of the chromosomes were the common abnormalities
observed associated with the cryopreservation of swamp
buffalo (SB) oocytes.
Keywords: swamp buffalo, oocytes, germinal vesicle
stage, cryopreservation
*Proceedings of the PSAS 40 th Scientific Seminar and
Annual Convention. October 23-24, 2003. Manila,
Philippines. p. 4.
R-46
NON-SURGICAL EMBRYO RECOVERY IN THE
WATER BUFFALO*
M. B. Ocampo, PhD Student, Hokkaido University
R. S. Uenishi, M. S. Student, Hokkaido, University
C. A. Valdez, PhD Student, Hokkaido, University
J. F. Pastor, Student, CVSM, CLSU
L. C. Cruz, Prof., DAS-CA, CLSU and Project Leader, PCRDC-
PCARRD, CLSU
H. Kanagawa, Professor, Hokkaido University
This study was undertaken to evaluate the applicability of
the cattle non-surgical embryo recovery technique, i.e.,
the ebb and flow system of the uterus in the water buffalo.
Other factors relevant to embryo recovery were also
studied. Three river buffaloes and one swamp buffalo at
the PCRDC were used in this study. Selected animals
were based on their reproductive cycle. Each buffalo was
first injected with 25 mg prostaglandin F 2 alpha (PGF 2
alpha) followed by 2000 IU of pregnant mare serum
gonadotropin (PMSG) ten days later. A second injection of
25 mg PGF 2 alpha was given 48 hour after PMSG injection.
Seventy-two hours later, the animals came in heat and
gonadotropic hormone (GnRH) was injected at 250 ug/
animal. Confirmation of estrus was done through physical
examination. Insemination was carried out using three
straws of thwed frozen semen Murrah buffalo (MB) semen
per animal. One straw was deposited in each of the two
uterine horns upon detection of estrus and another straw
deposited in the body of uterus 12 hours later. Non-surgical
embryo recovery was undertaken using the protocol used
for cattle. The number of ovulation was estimated by
counting the corpus luteum (CL) via rectal palpation. The
CL of the water buffalo was found to be smaller, more
deeply imbedded and generally has a less-pronounced
ovulation papilla than that of domestic cattle. Details of
embryo recovery performed in this study are presented
and discussed. Explanations for the results obtained are
presented. The authors recommended more detailed studies