Abstract

The present study aimed to determine plasma β-endorphin and cortisol concentrations in cattle with reproductive disorders (dystocia and retained placenta) and weakness body condition score during periparturient period. Stress may cause an overproduction of beta-endorphins and free radicals. Twenty multiparous Friesian cows weighing 400–650 kg aged 6-10 years and between (3-8) parities at late pregnancy period was used for two months before parturition. From ten days before the expected birth date the birth canal of each animal was monitored by rectal and vaginal palpations, and the body temperature was checked daily to predict the probable time of parturition. Animals were divided into four groups according to parturition disorders’ five animals in each one. First group delivered spontaneously at term with no obstetrical assistance(A), second group delivery was at term but was accompanied by dystocia(B), third group delivery was at term but was accompanied by retained placenta(C), and fourth group delivery was at term but animals showed weakness body condition score (D). Results illustrated that Plasma β-endorphin level in Friesian cattle during pregnancy state increased gradually through gestation period. It reaches its highest level during the third trimester due to stressful state. Also, it reaches its peak at zero time of parturition by appearing its analgesic action. Meanwhile, it decreases gradually towards re-establishment of ovarian cycle. Generally, cows suffering reproductive disorders had a clear impact on blood plasma β-endorphin concentration around parturition process.

Keywords

cattle, ?-endorphin, cortisol, reproductive disorders