Vie CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., PARIS, 1968, VOL. II

AN ATTEMPT TO SYNCHRONIZE ESTRUS IN SOWS BY APPLYING
PROGESTERONE AND GONADOTROPIC PREPARATIONS

VARADIN M,,MARJANOV M,
Veterinary Faculty,Sarajevo,Yugoslavia

In zootechnology different methods are increasing-
ly applied with the view of synchronizing estrus in
domestic animals.The synchronization of estrus in
sows is particularly important from the aspect of
breeding- and fattening technology.Ulberg,Grunner
and Casida(cit.4)prevented the occurrence of estrus
by applying 50 and 100 mg of progesterone daily to
sows over a period of 14 days.The sows came on heat
6-7 days after the treatment but the number of fer-
tilized ova was considerably lower than in the con-
trol animals.Neller(3)recommends to combine proge-
sterone and gonadotropic hormones in order to syn-
chronize estrus in sows.Dziuk and Polge(l)admini-
stered progesterone orally to sows and subsequently
injected i/m gonadotropic preparation into them,Ovu~
lation was provoked in 94% of cases but in most of
them there were no symptoms of estrus.However,by
combining with estrogene preparations these authors
managed to provoke estrus in 43% of cases.By apply-
ing estrogene preparations Harjanov(2)provoked est-
rus in 91,3% of sows but the rate of conception was
very low.Zavadovskij(6)and Varadin(5)applied PMS
and achieved the synchronization of estrus,a satis-
factory rate of conception and an increased ferti-
lity of sows.

As the daily injecting of progesterone into sows
can hardly be carried out under the circumstances
of production we combined depo-progesterone with
PMS with a view to synchronizing estrus.

MATERIAL AND METHODS,.Our investigations were car-
ried out on the sows of the Large White breed.We
used the depo-progesterone preparation 16476 b,
"Hoechst",with prolonged effect,which contains 125
mg of progesterone in 1 ml and PMS(Serogonin) with
180 M.Us,in 1 ml.Different doses of the depo-proge-
sterone preparation were administered to sows and
its effect upon the manifestations of estrus obser-
ved for 10 days.On the 11th day PMS was applied in
the dose of 4 M.U,per kg of body weight and the
occurrence of estrus observed for the following 10
days.One group of sows was given only PMS.After the

1535