age (redirected from ager)

age (aj)

1. the duration, or the measure of time, of the existence of a person or object.

2. the measure of an attribute relative to the chronological age of an average normal individual.

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achievement age  the age of a person expressed as the chronologic age of a normal person showing the same proficiency in study.

bone age  osseous development shown radiographically, stated in terms of the chronological age at which the development is ordinarily attained.

chronological age  the measure of time elapsed since a person's birth.

fertilization age  the age of a conceptus defined by the time elapsed since fertilization.

gestational age  the age of a conceptus or pregnancy; in human clinical practice, timed from onset of the last normal menstrual period. Elsewhere the onset may be timed from estrus, coitus, artificial insemination, vaginal plug formation, fertilization, or implantation.

mental age  the age level of mental ability of a person as gauged by standard intelligence tests.

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age (j)

n.

The length of time that one has existed; duration of life.

v.

1. To become old.

2. To manifest traits associated with old age.

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age,

n the period of time a person has existed or an object has existed.

age, biological,

n the age determined by physiology rather than chronology. Factors include changes in the physical structure of the body as well as changes in the performance of motor skills and sensory awareness.

age, chronologic,

n age determined by the passage of time since birth.

age determination,

n (by teeth), an estimate of age from the stage of tooth development and/or pattern of wear.

age distribution,

n a grouping of the persons within a population on the basis of birth date.

age factors,

n.pl variables affected by time since birth.

age hardening,

n See hardening, age.

age of onset,

n the chronologic age of the patient at which the disease, affliction, or disability appeared.

age, psychological,

n a subjectively experienced age based on a person's behavior, or “how old they feel.”

age, skeletal,

n the age based on skeletal measurements relative to chronological skeletal development.

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age

1. the duration, or the measure of time of the existence of an animal or object.

2. to undergo change as a result of passage of time.

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age adjustment

see data adjustment.

age associated disease

diseases which occur at particular ages, either because of changes in the animal's biochemistry or immunity or because of variations in exposure of the animals because of a change in management.

age descriptor

terms other than years used to indicate the age of animals, e.g. two-tooth, first-lactation.

age determination

in the absence of explicit records about birth dates the estimation of age is a frequent task for veterinarians. The eruption, then the growth of teeth to apposition and then the wear of the teeth are the best guide to age in horses, cattle, sheep and goat, but not in the pig. In the pig and the dog some assistance can be obtained from examination of the teeth, but the general appearance of the animal and the history are the best means. See also rule of six.

age distribution

the proportion of the total population which is in each of the specified age groups.

first joining age

a critical point in the economy of a herd or flock. In seasonal animal production systems unnecessary delay may cause loss of a year's productivity for each female. Starting too early may cause losses due to difficult parturition in small dams and a poor conception rate.

age groups

cattle and sheep being grazed extensively are commonly segregated into age groups because they are dealt with as groups for purposes of mating, vaccination, prophylactic treatment and eventually culling for old age.

age-matched control

in a comparison of performance between groups it is desirable to create the groups by pairing a series of treatment animals and control animals for all significant variables, of which age would be one of the most important.

age pigment

lipofuscin.

slaughter age

the age at which the animals in a group are to be slaughtered. Varies with the meat objective, the price in the market, opportunities for replacement and the capacity to carry additional animals on the feed available.

age-specific death rate

the death rate for a specified age group as a proportion of a total number of specified animal × time period, such as cow × years.

weaning age

see weaning age.