Different "EFFECT"s in Reproduction (Bruce, Whitten, Lee boot, Vandenbergh, Coolidge, McClintock, Dormitory, Audience effect)

Bruce effect 

         1. It is also known as pregnancy block effect.

       2. It refers to the spontaneous abortion or reabsorption of the embryo in the female by exposure to an unfamiliar male. Exposure to the odour of a strange male activates a neuroendocrine reflex leading to implantation failure.

Whitten effect

          1. In the presence of adult male, his pheromones induce estrus in female.

         2. Female animals undergo estrus synchronization, if a group of female animals housed together with a male or when a male animal introduced into the group of females. Likewise, pheromones produced by male sheep and goats can induce out-of-season ovulation in females (“male effect”).

3. Nearly 50% of the does will be in estrus on the third day after introduction of a buck.

Lee-Boot effect

          Groups of females housed together and isolated from males, will undergo anestrous (or suppressed oestrous cycles or prolonged oestrous cycles).

Male effect (Ram effect or Buck effect or Boar effect)

         1. Exposure of ram to a group of ewes that have been kept apart from the rams for a period of time can stimulate estrus and ovulation in females.

2. This method of biostimulation is used in the sheep, goat and pig management to facilitate synchronization of both estrus and ovulation.

Vandenbergh effect

The induction of early puberty (first estrus cycle) in prepubertal female mice occurs due to the result of exposure to urine of a sexually mature dominant male mice. Exposure to male urine induces the release of GnRH, which is responsible for the first estrus.

Menstrual synchrony or McClintock effect or Dormitory effect

The onset of menstruation or menses becomes more synchronized together in time in women who begin to live together in a close proximity. Women's pheromones interact when they are in close proximity, causing them to have their period at the same time.

Coolidge effect

          Males exhibit renewed sexual interest when the novel female in available to have sex, even after sexual satiety. Sexual interest is increased in male animals when they are exposed to different females rather than exposure to same female.

Audience effect

          The presence (audience) of a larger, dominant male can inhibit the sexual behaviour of subordinates. Submissive rams, mounted and ejaculated less when viewed by two dominant rams than when tested alone.