English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

I MPROVED methods for producing the various steroid hormones have increased their availability for experiments with large domestic animals and have made it possible to study their effects on the pituitary, on the reproductive organs and on the modification of the estrous cycle. Asdell, de Alba and Roberts (1945) found that estrus could be induced in ovariectomized heifers by injections of 600 R.U. of estradiol over a 3-day period. Dutt and Casida (1948) reported that the estrous cycle of the ewe could be controlled and synchronized by injections of progesterone. Hansel and Trimberger (1952) found that 5 to 10 mg of progesterone injected at the beginning of estrus hastened ovulation and shortened the duration of receptivity in cows. Cole, Har t and Miller (1945) found that injections of testosterone propionate increased the incidence of behavioral estrus in ewes receiving injections of PMS. Characteristic changes in the composition of semen and in spermatozoa can be produced with exogenous steroid hormones (Cupps, Laben and Rahlmann, 1960a; Cupps et al., 1960b; Cupps and Briggs, 1965; Matsuyama, Richkind and Cupps, 1967; Richkind, Matsugama and Cupps, 1967). The objectives of this paper are to review some of the effects of exogenous steroid hormones in the bovine, particularly in the female, and to report some of the changes produced by them.

Steroid effects on the reproductive system in the bovine.