In the animal kingdom, the general term gland falls into two major categories with further subtypes falling under each of these.
An Exocrine gland is distinguished by the fact that it excretes its essential product by way of a duct to some environment external to itself, be it either inside the body or on a surface of the body.
Secondary sex characteristics are features that appear during puberty, especially those that distinguish the two sexes of a species, but that are not directly part of the reproductive system. They are believed to be the product of sexual selection for traits which give an individual an advantage over its rivals in courtship and aggressive interactions.]citation needed[ They are distinguished from the primary sex characteristics — the sex organs — which are directly necessary for reproduction to occur.
Well-known secondary sex characteristics include manes of male lions and long feathers of male peacocks. Other dramatic examples include the tusks of male narwhals, enlarged proboscises in male elephant seals and proboscis monkeys, the bright facial and rump coloration of male mandrills, and horns in many goats and antelopes. Male birds and fish of many species have brighter coloration or other external ornaments. Differences in size between sexes are also considered secondary sexual characteristics.
Dairy farming is a class of agricultural, or an animal husbandry, enterprise, for long-term production of milk, usually from dairy cows but also from goats, sheep and camels, which may be either processed on-site or transported to a dairy factory for processing and eventual retail sale.
Most dairy farms sell the male calves born by their cows, usually for veal production, or breeding depending on quality of the bull calf, rather than raising non-milk-producing stock.]citation needed[ Many dairy farms also grow their own feed, typically including corn, and hay. This is fed directly to the cows, or is stored as silage for use during the winter season.
The reproductive system or genital system is a system of sex organs within an organism which work together for the purpose of reproduction. Many non-living substances such as fluids, hormones, and pheromones are also important accessories to the reproductive system.[dead link] Unlike most organ systems, the sexes of differentiated species often have significant differences. These differences allow for a combination of genetic material between two individuals, which allows for the possibility of greater genetic fitness of the offspring.
A mammary gland is an organ in female mammals that produces milk to feed young offspring. Mammals get their name from the word "mammary." In humans, the mammary glands are situated in the breasts. In ruminants such as cows, goats, and deer, the mammary glands are contained in the udders. The mammary glands of mammals other than primates, such as dogs and cats, are sometimes called dugs.
A ruminant is a mammal that digests plant-based food by initially softening it within the animal's first compartment of the stomach, principally through bacterial actions, then regurgitating the semi-digested mass, now known as cud, and chewing it again. The process of rechewing the cud to further break down plant matter and stimulate digestion is called "ruminating".
There are about 150 species of ruminants, which include both domestic and wild species. Ruminating mammals include cattle, goats, sheep, giraffes, yaks, deer, camels, llamas, antelope, and some macropods. Taxonomically, the suborder Ruminantia includes many of those species except the tylopods, monkeys, and marsupials. Therefore, the term 'ruminant' is not synonymous with Ruminantia. The word "ruminant" comes from the Latin ruminare, which means "to chew over again".