چکیده (انگلیسی):

Repeat breeding in buffaloes was evaluated in terms of incidence, risk factors and
diagnosis. The incidence of repeat breeding is low in buffaloes however in different
studies the incidence varied from 0.70% to 30%. Because of seasonal suppression of
fertility repeat breeding in buffaloes should be limited to the breeding season. Spring and
winter calving, first parity, peri-parturient disease and lactation are significant risk factors
for repeat breeding in buffaloes. The etiologies of repeat breeding in buffaloes can be
failure of fertilization and early embryonic deaths. Only a few of causes of failure of
fertilization have been identified in buffaloes. Ovulatory disturbances and ovarian cysts
are uncommon in buffaloes and cysts have poor clinical manifestation. Endometritis is the
common female cause of fertilization failures in buffaloes whereas poor semen quality
and improper insemination are the bull side factors for fertilization failures. Early embryonic
deaths are common in buffaloes mated/inseminated during the end of the
breeding season due to a low luteal progesterone however embryonic deaths occur late
(<25 days) in buffaloes. Diagnostic approaches for repeat breeding include vaginoscopic
and transrectal examination and uterine cytology for genital health. More precise evaluations
of the ovarian and uterine function can be obtained by ultrasonographic and
hysteroscopic examinations performed sequentially however, precise diagnosis of the
cause of repeat breeding seems difficult.