Stimuli from the environment are registered by the senses and transmitted to the brain. Sensory perceptions can be of a different nature. The eyes (light or the sight of other animals of the same species), the nose (sex odours), and the tactile senses register information from the environment, and the optic nerve, olfactory nerve and [...]
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In temperate climates, many species are seasonal breeders. Sheep, goats and horses are examples of them. This means that periods of sexual activity (the oestrus season) are alternated with periods of sexual inactivity (the anoestrus season).
In sheep for instance, sexual activity starts when the day length increases (long-day breeders). The difference in breeding season between [...]
Classically, labor is divided into 3 stages:
1st stage: Cervical relaxation and dilatation;
2nd stage: Production of young
3rd stage: Expulsion of the placenta.
In animals such as dogs, that produce more than one foetus, the stages alter as each individual foetus is produced.
During the first stage, which lasts from 4 hours (average) to 36 hours in [...]
Fertilisation in the queen takes place in the oviducts and 6-8 days post-mating the blastocysts migrate into the uterus. Implantation is thought to occur 11-14 days post-mating.
Pregnancy is most commonly confirmed by abdominal palpation: a series of discrete, firm spherical uterine enlargements can be readily felt by days 17-25 of gestation. Developing kittens can be [...]