SYNCHRONIZATION OF FERTILIZATION OF EWES USING “RAM EFFECT”
Keywords:
FERTILIZATION, RAM EFFECTAbstract
It is made an overview of the author’s own experiments and published literature for the essence
of factors which influence the ability to change the time for fertilization and synchronization of
fertility of ewes by using the so called “ram effect”. Through the proper use of the “ram effect” it
could be achieved synchronization of fertility of ewes with the result that within 10 to 13 days, at
the beginning of the lambing period, it is possible to be lambed 40 to 50% of all ewes. Furthermore,
this method allows adjusting the time of fertilization of ewes in order lambs for slaughter to be suitable
for sale when their prices are most favorable or to achieve other economic benefits. Depending on the
breed it is possible displacement of fertilization with 2 to 4 weeks. The response rate of ewes to the
“ram effect” is not the same and it depends on the breed, feeding and respectively the body condition
score, season, weather conditions, libido of teaser rams and other factors. Maiden ewes react weaker
than adult ewes. The “ram effect” is greater when approaching a natural breeding season but it still occurs in the middle of breeding season. The “ram effect” is easy to use, inexpensive and environmentally
safe method justifying its use in sheep breeding. The only disadvantage of the method is the need of
more rams for natural insemination of many ewes for a short period. However, this is an advantage for
artificial insemination
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