Herd(redirected from herd level test)
Also found in: Dictionary, Thesaurus, Medical.
a group of beef cattle.
Animals in a herd are selected according to sex, age, liveweight, and fattiness. Herds are formed during the zootechnical and veterinary examination of the cattle before the beginning of pasturing. The size of the herds in meat sovkhozes is 150–200 head of younger animals, 150–200 head of fattened adult animals in steppe regions, and 100–150 in forest and forest-steppe regions. Each herd is managed by a team of two to four herdsmen.
(1) A group of mammals of the same species with interdependent behavior; that is, they remain close to one another for a significant period of time, behave similarly, often have the same rhythm of activity (for example, the simultaneous diving of whales), and travel in the same direction. Herd formation is characteristic of cetaceans, artiodactyls, perissodactyls, and monkeys. The composition (in terms of age and sex) and size of a herd fluctuate, thereby distinguishing herds from other groups of animals with interdependent behavior, for example, families and harems.
The maximum size of a herd is determined by the possibilities for mutual coordination of behavior. A herd may consist of dozens of individuals among whales and monkeys and 1,500 to 2,000 individuals among ungulates (for example, reindeer, saiga, and gnu). The largest herds are formed during seasonal migrations, after which they break up into smaller groups (families, harems). The animals in a herd orient themselves by the behavior of their neighbors (signals of the presence of food, appearance of a predator). Following the example of its leader, a herd may select a safer route during flight from a predator or during travel toward a watering place or shelter, especially during the migration period. Imitation of nearby individuals predominates in the behavior of many herd members over free decision-making, which is characteristic of solitary animals.
When animals are in a herd they permit man to approach fairly closely and possibly to control them. The patterns of herd behavior are widely used in pasture livestock raising, since domesticated hoofed animals are usually gregarious.
L. M. BASKIN
(2) A group of animals kept together on a farm for maintenance, fattening, or pasturing, for example, a herd of beef cattle or a herd of horses.
(3) The total number of animals of one species on a farm. The composition (sex, age, and production groups of animals), purpose, and periods of use of a herd vary with the organizational and economic conditions of herd reproduction. The necessary composition is maintained by planned rotation of the herd.