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

Heat Synchronization by Androgen-Estrogen Combinations
in Sows and Gilts (Preliminary Report)

by

2

B BmtALe . W SOBkLe & And: 0. Ihanes?

1) Director, Inst. of Veterinary Science, Syntex
Research, Palo Alto, California, U.S.A.

2) Institut fiir Tierzucht und Haustiergenetik,
Universitdt Gottingen, Germany

Cycle synchronization in pigs on a praetical scale
has been achieved up to now mainly by the use of the
ICI compound 33828 (AIMAX) or by simultaneous weaning
of litters after lactation respectively. By these me-
thods na precise heat synchronization can be obtained:
heat presentation is spread from day 2 to day 9 (or
more) after end of treatment or weaning respectively.
For concentrations of farrowing dates this range might
be acceptable, but not for more sophisticated procedures
like A.I. and egg transfer experiments. PMS and HCG in-
jections after treatment or weaning improve heat syn-
chronization but are impracticable because several in-
Jections are necessary.

Since some years our group has been engaged in ex-
ploring the heat inducing capacity of androgen-estrogen
combinations in cattle (Jochle, 1964), sheep (Witt, 1967)
and pigs (J6chle et al., 1967; Smidt, 1968). This re-
port is related tothe heat inducing capacity of two pre-
parations in gilts and sows.

a) Suitest(R) 1 : 2.5 mg testosterone enanthate and
1.0 mg estradiol valerate per ml

b) Substance 2 : 2.5 mg testosterone undecenoate a.
1.0 mg estradiol valerate per ml
=l

iF

 

1: WDT, Hannover/Germany and Veterinaria A.G.
Zirich / Switzerland

2: Syntex

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