I. Kita et al., HISTOLOGICAL DIFFERENCE BETWEEN RETROGRADE CORPORA-LUTEA OF PREGNANCYAND THOSE OF ESTRUS IN SIKA-DEER, CERVUS-NIPPON, Journal of veterinary medical science, 56(2), 1994, pp. 309-314
Histological characteristics of retrograde corpora lutea (RCL) were ex
amined for 105 pairs of ovaries of adult female sika deer, Cervus nipp
on. Animals were captured in various seasons at Mt. Goyo, Iwate Prefec
ture, the northern part of Japan. No histological differences were rec
ognizable between RCL of pregnancy and retrograde accessory corpora lu
tea (RACL), so far as examined by means of hematoxylin-eosin and Weige
rt's resorcinfuchsin staining. They were both irregularly shaped and h
ad well developed arteries in their thick capsules and a number of sma
ll arteries in the parenchyma. These arteries showed the proliferation
of elastic fibers showing elastosis in older RCL. The total number of
these retrograded bodies per female increased with age, suggesting th
at both the retrograded bodies would retain in the ovaries over 7 year
s. RCL of estrus were small hyaline bodies scattered with some degener
ated luteal cells in the hyaline matrix. They were distinguishable fro
m those of pregnancy since the capsule and parenchyma in those of estr
us were poorer in blood vessels. RCL of estrus appeared in October and
November but were rarely seen in February and March, suggesting that
they will disappear within three months after ovulation.