J. Sci. Dev. 2010, 8 (Eng.Iss.1): 100 - 110 HA NOI UNIVERSITY OF AGRICULTURE
100

CHARACTERISTICS OF REPRODUCTION OF THE WATER BUFFALO AND
TECHNIQUES USED TO IMPROVE THEIR REPRODUCTIVE PERFORMANCE
Đặc điểm sinh sản và một số kỹ thuật ứng dụng
nhằm cải thiện năng suất sinh sản của trâu
Nguyen Hoai Nam
Faculty of Veterinary Medicine, Hanoi University of Agriculture, Vietnam
Corresponding author : (066)874389148
TÓM TẮT
Thành thục muộn, động dục thầm lặng, khoảng cách lứa đẻ dài và sinh sản theo mùa là những
đặc điểm ảnh hưởng tới năng suất sinh sản của trâu. Nhiều biện pháp kỹ thuật đã được áp dụng
nhằm cải thiện hiệu quả sinh sản của loài gia súc này. Sử dụng hoóc-môn gây động dục sau đó thụ
tinh tại một thời điểm nhất định là kỹ thu
ật được ứng dụng nhiều và cho một số kết quả khả quan.
Gây rụng trứng nhiều hay hút trứng có thể thu được một số lượng lớn phôi, trứng trong một thời
gian ngắn nhưng tỷ lệ trứng phát triển đến giai đoạn thụ tinh và tỷ lệ thụ tinh trong phòng thí nghiệm
còn thấp. Cấy truyền phôi dù đạt được một số thành tựu nhưng hiệu quả của ph
ương pháp này chưa
ổn định. Nghiên cứu nhằm tăng năng suất sinh sản ở trâu nước là một vấn đề thiết yếu.
Từ khóa: Sự thụ tinh, sự rụng trứng, sinh sản, trâu nước.
SUMMARY
Late puberty, silent heat, long calving interval and seasonal breeding are characteristics those
hamper the reproductive performance of the water buffalo. Several techniques have been used to
improve their reproductive efficiency. Ovulation program - fixed time artificial insemination (Ovsynch-
TAI) has been applied as the most popular solution with prospective results. Superovulation
demonstrates a fairly low number of embryos per buffalo in each session. Ovum pick-up (OPU) is
superior to superovulation since it could yield quite a large amount of oocytes in a short time.
Unfortunately, in vitro maturation (IVM) and in vitro fertilization (IVF) rates are still low. Embryo
transfer has obtained some achievements. However, the efficacy of this technique is not really stable.

water buffalo, several techniques such as artificial
insemination, superovulation, ovum pick-up, in
vitro maturation, in vitro fertilization and embryo
transfer have been applied with various
achievements.
The purpose of this article is to summarize the
characteristics of reproduction in water buffaloes
and solutions used to improve their reproductive
performance.
2. CHARACTERISTICS OF REPRODUCTION
IN THE WATER BUFFALO
2.1. Late puberty
The age at puberty in buffaloes is much higher
than that in cattle. In the male buffalo, the
establishment of spermatogenesis is complete at the
age of 24 months (McCool and Entwistle, 1989)
compared with 4 months in cattle (Curtis and
Amann, 1981). Though sperm production of swamp
buffaloes is established at 12-15 months of age,
they do not show in the ejaculation until buffaloes
reach 2 years old (McCool and Entwistle, 1989).
In the female swamp buffalo, puberty appears
individually, seasonally, nutritionally and
managerially different. According to a research in
the Thai swamp buffalo, heifers reached puberty at
the age of 3-4 years old when they were at 55-60%
of their adult body weight (Bodhipaksha et al.
1987). In another research, the Thai swamp buffalo
obtained puberty at around 24-25 months old
(Kamonpatana et al. 1987). The swamp buffalo in

growing follicles. Similarly, number of Graafian
follicles > 1 mm in diameter is less while the
follicular atresia is greater than that of cattle
(Noakes et al, 2001). This may be a cause of poor
reproductive performance in this type of animal.
2.3. Silent heat
Due to the low level of blood oestradiol-17
beta, the expression of estrus in buffaloes is very
poor. Silent heat is one of the deleterious features to
the reproductive performance in the buffalo. Estrus
often passes unoticedly, especially in the hot and dry
seasons when grass, wallowing pools and shades are
in deficiency which made the expression more
dubious. A research in the Pakistani river buffalo
showed that 51.5% of estrus was the silent heat
(Qureshi and Ahmad, 2008). According to a study in
the Egyptian river buffalo, there were two patterns of
follicular waves in which the three follicular waves
dominated the two follicular waves (Barkawi et al.
2009). In contrast, the one wave estrus cycles in the
Thai swamp buffalo were depicted to be 22.7%
while the two wave- patterns were 77.3%
(Promdireg et al., 2004). Study of the follicular
waves in the estrus cycles of the river buffalo
showed that the one follicular wave patterns were
quite usual (Awasthi et al. 2006). In one wave
model, the ovulatory follicles persisted much longer
than those in the 2 wave-pattern, and at the middle of
the cycle there was a regression before a
resurrection. The growth rate of ovulatory follicles

The short estrus was hypothetically induced by the
one-wave cycle (Baruselli et al. 1996). This type of
follicular wave cycle also generates variable
durations of estrus which cause difficulties to the
estimation of ovulation and appropriate time of
artificial insemination.
The time of ovulation was reported to depend
on the protocols used to induce estrus (Warriach et
al. 2008). In the PGF2 alpha and GnRH-induced
estrus river buffaloes, the durations of standing
estrus were 14.2±0.8 and 8.9±0.6 h, respectively.
The intervals of ovulation after standing estrus
were 30,6±1,5h and 15,0±0,8h in the PGF
2
alpha
and GnRH–induced estrus buffaloes, respectively
(Warriach et al. 2008). The ovulatory response of
the river buffalo was found to be from 57.6%-
84.4% when eCG and CIRD were applied in
ovulation synchronization (Murugavel et al. 2009).
2.5. Seasonal breeding
The water buffalo is the multiestrus animal
and the sexual activities can occur all round year.
Nonetheless, the ovarian activities have shown to
be characterized by the seasonal low breeding
period during the hot season (Sule et al. 2001). The
water buffalo is heat intolerant by nature (Chiu,
2003) they need shade and water or mud to get rid
of the heat from the environment. In the summer,
while the temperature is high, pools of water

proportion of normal morphological spermatozoa
was much higher in the breeding season than those
in the low breeding season though the total amount
of spermatozoa was the same. This result
contradicted the conclusion that season did not
have deleterious effects on the sperm quality in the
swamp buffalo used as artificial insemination sires
in Thailand (Koonjaenak et al. 2007). However, in
that study, the experimented buffaloes were used in
semen collecting station for artificial insemination
where they were chosen, managed and taken care
of very strictly and carefully and might not
represent the buffaloes in the field.
The seasonal reproductive characteristic in
water buffalo also depends on melatonin excreted
from pineal gland during the night and represents
the endocrinal signal of the light-dark rhythm in the
environment (Zicarelli et al. 1997, Di Palo et al.
1997).
2.6. Long postpartum anestrus
The resumption of estrus postpartum is a
critical factor to achieve a satisfactory production
in buffaloes. In dairy cattle this period should be in
about 60-80 days and conception must be obtained
by 85-100 days post-calving to get desirable
Characteristics of reproduction of the water buffalo and techniques used to improve
103
benefits. Unfortunately, postpartum estrus in
buffaloes always comes much later than this figure.
The long postpartum anestrus in the buffalo

the most prevalent disease (Azawi et al 2008). It
was reported to be about 12.3% in a research on
genital tracts of Iraqi buffaloes. Other types of
metritis were also depicted however the occurrence
was much lower with the prevalence of hydrometra,
mucometra, pyometra were 0.2%, 0.7%, 0.49%,
respectively (Azawi et al. 2008). Endometritis was
also documented to be very high in Egyptian and
Iranian buffaloes: 22.4%-47.9% (Al-Fahad et al.,
2000; Alwan etal., 2001, Ghanem et al., 2002;
Moghaddam et al. 2004; Moghami et al. 1996).
Jainudeen et al. (1983) reported that uterine
involution was at 28±6 days and 32% of the
suckled Malaysian swamp buffaloes showed the
first ovulation after calving 90 days, 68% of them
were anestrus within 150 days postpartum.
Subclinical uterine infection was supposed to
slower the appearance of the first estrus post
calving (El-Sheikh and Mahamed, 1976).
Elongation of postpartum anestrus interval
was found in the river buffaloes those produced
more than 8kg of milk per day than those produced
less than 8 kg of milk per day (El-Fadaly et al.
1980, El-Azab et al. 1984). Suckling obviously
prolongs time of postpartum anestrus. Jainudeen et
al. (1984) reported the weaned buffaloes at 30 days
postpartum showed the first estrus earlier than
those were suckled of 42 ± 8 and 55 ± 10 days,
respectively. Similarly, milked buffaloes had longer
acyclic interval of 72 ± 11 days compared with 44

gestation and low response after parturition
regardless of the stable LH and FSH contents in the
pituitary may suggest that this is one of the reasons
of long postpartum anestrus in the buffalo.
Reproduction of water buffaloes is greatly
hampered by late attainment of puberty, seasonality
of breeding, long postpartum anestrus. Moreover,
silent heat and variable time of ovulation make the
estrus detection very difficult. All of those
mentioned characteristics bring about the poor
performance of both reproduction and production
of the water buffalo.
Nguyen Hoai Nam
104
3. IMPROVEMENT OF REPREDUCTIVE
PERFORMANCE IN THE SWAMP
BUFFALO
3.1. Artificial insemination
Artificial insemination (AI) has been used
widely on dairy and beef cattle with satisfactorily
stable conception rate whereas that in water
buffaloes was reported to be various and humble. AI
was mostly applied in buffaloes at fixed time
following the ovulation synchronization programs
(Ovsynch) which used several sexual hormones such
as GnRH, progesterone, PGF
2
-alpha, PMSG, LH and
estradiol-17 beta. The conception rates of water
buffaloes were reported to range from 22.2% to

between day 25 and day 40 post insemination was
reported to be very high of 21%-50% (Campanile et
al. 2005, Campanile et al. 2008, Vecchio et al.
2008).
3.2. Superovulation
For the low amount of primordial follicles in
the ovaries, the ovulation response in buffaloes is
much less effective than that in cattle. Progesterone
mare’s serum gonadotropin (PMSG) and follicle
stimulating hormone (FSH) have been the most
popular hormones used in superovulation programs.
Due to a long half life (Schams and Himmler,
1978), PMSG induces a second follicular wave
with anovulatory follicles after the first ovulation.
These follicles secrete a large amount of oestradiol-
17beta that far exceeds the preovulatory
concentration which results in an imbalance of
progesterone:oestradiol-17beta ratio in the
follicular fluid and unfavorable condition for the
maturation and implantation of the oocytes and
embryos in the oviduct and uterus (Schallenberger
et al. 1990). The use of monoclonal antibodies
against PMSG could reduce the peripheral inhibin
of superovulated buffaloes and resulted in better
results (Palta et al. 1996). Several efforts have been
also made to increase the response of ovaries and
production of embryos as well. The
supplementation of GnRH at the standing heat and
8-12h after standing heat was conducted
(Techakumphu et al., 2001). The numbers of

105
also collected 1.6±0.1 and 1.0±0.3 oocytes/buffalo
in the high and low breeding season, respectively
(Manjunatha et al. 2009). Researches on Thai
swamp buffaloes showed a higher amount of 5.33 -
7.75 oocytes recovered from one buffalo
(Techakumphu et al. 2004a; Techakumphu et al.
2004b). Those authors suggested that five repeat
cycles of FSH and OPU did not influence the
follicular response to the super-stimulation or the
number of oocytes from the pre-pubertal and
buffalo calves. Ovum pick-up was studied in
buffaloes in different reproductive status with the
similar results (Promdireg et al. 2005). The
efficiency of PMSG used in OPU was found to be
higher than that of FSH when the yields of oocytes
collected were 8.3 ± 5 and 4.6±3.2, respectively
(Techakumphu et al. 2000a). However, another
study by the same authors gave a contradicted
result when the application of FSH and GnRH
tended to reproduce more oocytes collected/buffalo
than those used PMSG and GnRH, i.e. 9.0±6.4 and
8.4±1.1, respectively (Techakumphu et al. 2000b).
In vitro maturation and in vitro fertilization
rates of buffalo oocytes are substantially various. A
very low maturation rate of only 3% was
announced by (Songsasen and Apimeteetumrong,
2002). This rate was improved by 23.5-42.5% in
the study by Wani et al. (2004). Several reports
showed that the maturation rate was ranged

conception rates of buffaloes received fresh sexed
(26.5%) and unsexed (26.9%) embryos were higher
than those received frozen-thawed sexed (11.6%)
and unsexed (15.4%) embryos (Liang et al. 2008).
In another Chinese study, twenty-nine swamp
buffaloes were transferred fresh in vitro river and
F1 buffalo cross (river x swamp) embryos, 41.4%
recipients were pregnant and 10 calves were born
accounting for 34.5% (Liang et al. 2007). The
frozen effect on the conception rate was
demonstrated by Techakumphu et al. (2001).
Pregnancy rate in the fresh embryo transferred
buffaloes was 35.7%, much higher than that in
those transferred frozen-thawed embryos, i.e. 5.9%.
Low conception and calving rates were also
documented of 16.36% and 10.91%, respectively
(Hufana-Duran et al. 2004).
Certain of methods have been used to cope
with reproductive aspect of water buffaloes.
Artificial insemination, with some degree of
success, is a preferable choice. However, other
techniques such as superovulation, ovum pick-up,
in vitro maturation and in vitro fertilization have
limited application due to their low efficiency.
4. CONCLUSIONS
The water buffalo is characterized by
ineffectively reproductive performance. Late
puberty reduces the duration of fertile life of this
animal while silent heat and variable time of
ovulation cause the difficulty to the estrus detection

Al-Fahad TA, 2000. Morphological study of
abnormal cases of female reproductive system of
buffaloes in Basra Province. MSc Thesis,
College Veterinary Medicine, Baghdad
University, Baghdad, pp. 31–40.
Alwan AF, Abdul-Hammed AN, Khammas DJ.
(2001). A macroscopical study of abnormal
genitalia of Iraqi female bualoes. Iraqi J Vet
Sci, 14, 129–132.
Arya, J.S. and Madan, M.L. (2001). Post partum
reproductive cyclicity based on ovarian steroids
in suckled and weaned buffaloes. Buffalo J., 17
(3): 361-369.
Awasthi, M. K., Khare, A., Kavani, F. S.,
Siddiquee, G. M., Panchal, M. T., and Shah, R.
R. (2006). Is one-wave follicular growth during
the estrous cycle a usual phenomenon in water
buffaloes (Bubalus bubalis)? Anim Reprod Sci
92, 241-53.
Awasthi, M. K., Kavani, F. S., Siddiquee, G. M.,
Sarvaiya, N. P., and Derashri, H. J. (2007). Is
slow follicular growth the cause of silent estrus
in water buffaloes? Anim Reprod Sci 99, 258-68.
Azawi.O.I, Ali.A.J, Lazim.E.H. (2008).
Pathological and anatomical abnormalities
affecting buffalo cows reproductive tracts in
Mosul. Iraqi Journal of Veterinary Sciences.
Vol.22.No.2,2008 (59-67).
Bahga, C. S., and Gangwar, P. C. (1988). Seasonal
variations in plasma hormones and reproductive

Reproduction, Fac Vet Sci;Chulalongkorn
University ed. 118p.
Bongso, T. A., Hilmi, M., and Basrur, P. K. (1983).
Testicular cells in hybrid water buffaloes
(Bubalus bubalis). Res Vet Sci 35, 253-8.
Brown, J. L., Wildt, D. E., Raath, J. R., de Vos, V.,
Howard, J. G., Janssen, D. L., Citino, S. B., and
Bush, M. (1991). Impact of season on seminal
characteristics and endocrine status of adult free-
ranging African buffalo (Syncerus caffer). J
Reprod Fertil 92, 47-57.
Campanile, G., Neglia, G., Gasparrini, B., Galiero,
G., Prandi, A., Di Palo, R., D'Occhio, M. J., and
Zicarelli, L. (2005). Embryonic mortality in
buffaloes synchronized and mated by AI during
the seasonal decline in reproductive function.
Theriogenology 63, 2334-40.
Campanile, G., Vecchio, D., Di Palo, R., Neglia,
G., Gasparrini, B., Prandi, A., Zicarelli, L., and
D'Occhio, M. J. (2008). Delayed treatment with
GnRH agonist, hCG and progesterone and
reduced embryonic mortality in buffaloes.
Theriogenology 70, 1544-9.
Chaikhun.T, Tharasanit.T, Techakumphu.M,
(2009). Efficiency of ovulation synchronization
and fixed –time artificial insemination program
Characteristics of reproduction of the water buffalo and techniques used to improve
107
in swamp bufflo in small holder farms. In:
Proceeding of the Second FASAVA Congress,

Theriogenology 29 (1988), pp. 1401–1406.
Di Palo, R., Parmeggiani, A., Spadetta, M.,
Campanile, G., Esposito, L., Seren, E. and
Zicarelli,L. (1997). Influence of changing farm
on repeatability of melatonin plasma level in
Italian Mediterranean buffalo. In: Proc. Fifth
World Buffalo Congress, Caserta, Italy, 13-16
October:758-761.
Gasparrini, B., Boccia, L., Rosa, A. D., Palo, R. D.,
Campanile, G., and Zicarelli, L. (2004).
Chemical activation of buffalo (Bubalus bubalis)
oocytes by different methods: effects of aging on
post-pathogenetic development. Theriogenology
62, 1627-37.
Gasparrini, B., Boccia, L., Marchandise, J., Di
Palo, R., George, F., Donnay, I., and Zicarelli, L.
(2006). Enrichment of in vitro maturation
medium for buffalo (Bubalus bubalis) oocytes
with thiol compounds: effects of cystine on
glutathione synthesis and embryo development.
Theriogenology 65, 275-87.
Ghanem M, Shalaby AH, Sharawy S, Saleh N,
(2002). Factors leading to endometritis in Egypt
with special reference to reproductive
performance. J Reprod Sci 48, 371–375.
El-Azab, E.A., Mansour, H., Heshmat, H., Shawki,
G. (1984). The postpartum period and the future
fertility of the Egyptian buffalo. In: Proceedings
of the 10th International Congress on Animal
Reproduction and AI, vol. III, No. 424, Urbana,

Hegazy, M.A., El-Wishy, A.B., Youssef, A.H.,
Awadalla, S.A., Teleb, H.M. (1994a).
Interrelationship between pre-and/or post-partum
feeding levels, blood constituents and reproductive
performance of buffaloes. In: Proceedings of the
Fourth World Buffalo Congress, vol. III, San
Paulo, Brazil, pp. 632–633.
Hegazy, M.A., El-Essawy, S.A., El-Wishy, A.B.,
Youssef, A.H. (1994b). Effect of body condition
score on reproductive performance of buffaloes.
In: Proceedings of the Fourth World Buffalo
Congress, vol. III, Sao Paulo, Brazil, pp. 630-
631.
Honnappagol, S.S. and Patil, R.V. (1991). Oestrus
synchronization and fertility in buffalo heifers
Nguyen Hoai Nam
108
using Carboprost Tromethanine. Indian J. Anim.
Reprod., 12 (2): 177-179.
Hufana-Duran, D., Pedro, P. B., Venturina, H. V.,
Hufana, R. D., Salazar, A. L., Duran, P. G., and
Cruz, L. C. (2004). Post-warming hatching and
birth of live calves following transfer of in vitro-
derived vitrified water buffalo (Bubalus bubalis)
embryos. Theriogenology 61, 1429-39.
Ishaq, S.M. (1972). Ninth Annual Report.
Directorate of Livestock Farms, Punjab, Lahore.
Jainudeen, M.R., Bongso, T.A., Tan, H.S.,
(1982/1983). Postpartum ovarian activity and
uterine involution in the suckled swamp buffalo

and swamp buffalo. Anim Genet 38, 227-32.
Kumaresan, A. and Ansari, M.R. (2001).
Evaluation of conception rate in buffaloes
(Bubalusbubalis) with reference to semen
quality, stage of oestrus and inseminator. Indian
J. Anim.Sci.,71 (2): 144-145.
Le Xuan Cong, (1983). Performances in
Vietnamese Swamp buffalo. Buffalo Bulletin, 2
(2):12-13.
Liang, X., Zhang, X., Yang, B., Cheng, M., Huang,
F., Pang, C., Qing, G., Liao, C., Wei, S.,
Senatore, E. M., Bella, A., and Presicce, G. A.
(2007). Pregnancy and calving rates following
transfer of in-vitro-produced river and F1 (river
x swamp) buffalo (Bubalus bubalis) embryos in
recipients on natural oestrus or synchronised for
ovulation. Reprod Fertil Dev 19, 670-6.
Liang, X. W., Lu, Y. Q., Chen, M. T., Zhang, X. F.,
Lu, S. S., Zhang, M., Pang, C. Y., Huang, F. X.,
and Lu, K. H. (2008). In vitro embryo
production in buffalo (Bubalus bubalis) using
sexed sperm and oocytes from ovum pick up.
Theriogenology 69, 822-6.
Mahdy, A.E., El-Shafie, O.M., Rigalaty, H.A.,
(2001). Relative importance of some factors
affecting performance traits in a herd of
Egyptian buffaloes. Alex. J. Agric. Res. 46, 1-18.
Manjunatha, B. M., Gupta, P. S., Devaraj, M.,
Ravindra, J. P., and Nandi, S. (2007). Selection
of developmentally competent buffalo oocytes

preimplantation embryo in the superovulated
Characteristics of reproduction of the water buffalo and techniques used to improve
109
buffalo (Bubalus bubalis). Theriogenology 50,
637-49.
Misra, A. K., Rao, M. M., Kasiraj, R., Reddy, N.
S., and Pant, H. C. (1999). Factors affecting
pregnancy rate following nonsurgical embryo
transfer in buffalo (Bubalus bubalis): a
retrospective study. Theriogenology 52, 1-10.
Moghaddam AAI, Mamoei M, (2004). A survey on
some of the reproductive and productive traits of
the buffalo in Iran. 23rd World Buiatrics
Congress, Quebec, Canada, Abstract 2910.
Moghami SM, Saiyari M, Mayatri M, Sharma RN.
(1996). Pathology of uterus in buffalo
slaughtered in Ahwaz (Iran) abattoir. Buffalo J
12, 213–218.
Mohamed, A.A., El-Ashry, M.A. and El-Serafy,
A.M. (1980). Reproductive performance of
buffalo heifers bred at a young age. Indian J.
Anim. Sci., 50: 8.
Murugavel, K., Antoine, D., Raju, M. S., and
Lopez-Gatius, F. (2009). The effect of addition
of equine chorionic gonadotropin to a
progesterone-based estrous synchronization
protocol in buffaloes (Bubalus bubalis) under
tropical conditions. Theriogenology 71, 1120-6.
Neglia, G., Gasparrini, B., Di Palo, R., De Rosa, C.,
Zicarelli, L., and Campanile, G. (2003).

993-8.
Patel, K.K., Ninan, J., Suthar, B.N., Kavani, F.S.
(1992). Factors affecting fertile postpartum
estrus in Mensoni buffaloes. Cheiron 21, 39–43.
Perera, B.M.A.O., de Silva, L.N.A., Kuruwita,
V.Y., Karunaratne, A.M. (1987). Postpartum
ovarian activity, uterine involution and fertility
in indigenous buffaloes at a selected village
location in Sri Lanka. Anim. Reprod. Sci. 14,
115–127.
Paul, V., and Prakash, B. S. (2005). Efficacy of the
Ovsynch protocol for synchronization of
ovulation and fixed-time artificial insemination
in Murrah buffaloes (Bubalus bubalis).
Theriogenology 64, 1049-60.
Promdireg A , Na-Chiangmai A., Techakumphu
M, (2004). Follicular dynamics in swamp
buffalo cows (Bubalus bubalis). The 30th
Veterinary Medicine and Livestock De-
velopment Annual Conference, The Thai
Veterinary Medical Association Under the Royal
Patronage,Bangkok, p74
Promdireg, A., Adulyanubap, W., Singlor, J., Na-
Chiengmai, A., and Techakumphu, M. (2005).
Ovum pick-up in cycling and lactating
postpartum swamp buffaloes (Bubalis bubalis).
Reprod Domest Anim 40, 145-9.
Qureshi, M.S., Samad, H.A., Nazir Ahmad, N.,
Habib, G., Anjun, A.D., Siddiqui, M.M., (1998).
Reproductive performance of dairy buffaloes

A.H. (1994). Pubertal performance of Egyptian
buffalo heifers. Buffalo J., 10 (1): 61-66
Schallenberger, E., Wagner, H. G., Papa, R., Hartl,
P., and Tenhumberg, H.(1990). Endocrinological
evaluation of the induction of superovulation
with PMSG in water buffalo (Bubalus bubalis).
Theriogenology 34, 379-92.
Schams, D., and Himmler, V. (1978). The effect of
reduced water in take on peripheral plasma
levels of prolactin in heifers. Horm Metab Res
10, 360.
Songsasen, N., Yiengvisavakul, V., Buntaracha, B.,
Pharee, S., Apimeteetumrong, M., and
Sukwongs, Y. (1999). Effect of treatment with
recombinant bovine somatotropin on responses
to superovulatory treatment in swamp buffalo
(Bubalus bubalis). Theriogenology 52, 377-84.
Songsasen, N., and Apimeteetumrong, M. (2002).
Effects of beta-mercaptoethanol on formation of
pronuclei and developmental competence of
swamp buffalo oocytes. Anim Reprod Sci 71,
193-202.
Sule, S.R., Taparia, A.L., Jain, L.S. and Tailor, S.P.
(2001). Reproductive status of Surti buffaloes
maintained under sub-humid conditions of
Rajasthan. Indian Vet. J., 78 (11): 10491051
Techakumphu, M., Lohachit, C., Tantasuparak, W.,
Intaramongkol, C., and Intaramongkol, S.
(2000a). Ovarian responses and oocyte recovery
in prepubertal swamp buffalo (Bubalus bubalis)

estradiol supplementation on superovulation in
Swamp buffalo. Theriogenology 38, 471-8.
Uoc, N. T., de Rennis, F., Duc, N. H., Bui, L. C.,
Hanh, N. V., Linh, N. V., Thanh, N. T., Huu, Q.
X., Long, D. D., and Nguyen, B. X. (2007).
Effect of season on quality of oocytes, results of
in vitro maturation, and somatic cell nuclear
transfer in swamp buffalo. Reproduction,
Fertility and Development 19, 163-164.
Vecchio, D., Neglia, G., Di Palo, R., Prandi, A.,
Gasparrini, B., Balestrieri, A., D'Occhio, M. J.,
Zicarelli, L., and Campanile, G. (2008). Is a
Delayed Treatment with GnRH, hCG or
Progesterone Beneficial for Reducing
Embryonic Mortality in Buffaloes? Reprod
Domest Anim.
Vlakhov, K., Karaivanov, K., Petrov, M., and
Kacheva, D. (1986). [Superovulation and the
production of embryos in the water buffalo
(Bubalus bubalis) in Bulgaria]. Vet Med Nauki

23, 84-8.
Warriach, H. M., Channa, A. A., and Ahmad, N.
(2008). Effect of oestrus synchronization
methods on oestrus behaviour, timing of
ovulation and pregnancy rate during the
breeding and low breeding seasons in Nili-Ravi
buffaloes. Anim Reprod Sci 107, 62-7.
Zicarelli, L. (1997). Reproductive seasonality in
buffalo. Bubalus bubalis, 4, Suppl.: 29 - 52.