In the vagina small quantities of clear er greyish mucus of vary-
ing viscosity was observed.

The typical appearance of the vagina in normal luteal phase, with
a pale and relatively dry m.m. and closed, cerrugated pertio, was
noted only occasionally.

Clearly arberizing crystal formations were generally evident in
several areas of the smears of cervical mucus at the beginning
and the end of the treatment periocd. Between these times little
or no crystal formation was ebserved.

Hormone administration beginning in full luteal stage. Table 1
shows hew the incidence of palpable follicles increased around
the time of normal oestrus and remained high for the rest of the
treatment. Corpora lutea regressed almost completely when hormene

treatment continued for 17 days.

At the point where heat should normally have occurred but for
hormone treatment, the vaginal m.m. became pink and that of the
portio pink to red. The portio was smeoth and partially or fully
oepen with clear mucus at the external os. A fair amount of mucus
generally accumulated in the forward part of the vagina. Colour
was clear or greyish and visceosity relatively low.

Arborization of cervical mucus increased at the time of normal
oestreus from little or none te obvious arborization on several
parts of the smears.

Hormone administration beginning in the follicular stage. The in-
cidence of follicles rese at the expected time for normal heat.
Ovulation was prevented in 9 out of 11 heifers. Two heifers ovu-
lated without showing external signs of heat at the beginning of

treatment and c.l. developed from these ovulations (table 1).

During treatment the vaginal m.m. remained pink and the portie
m.m. pink to red. The portio was smooth and partially or fully
open with clear mucus in the external os.

An accumulation of mucus was usually present in the forward part
of the vagina. It was generally clear and either a little viscous
or thin.

Clear arborization was censtantly present during treatment. In-
creased arbeorization was noticed at the beginning of treatment
when the animals should normally have come on heat.

VULVA Marked enlargement of the vulva was observed in all
groups by the 4th day of treatment. This remained se far 2-6

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