age classes


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age classes

the classification of animals according to age is an important part of animal farming but is difficult to carry out and has limited value because of varying interpretations of the terms used. Some of the classifications, based on average farming practices, are:
Calf, birth to 1 year, yearling 1 to 2 years, heifer to first calf born. Calf and yearling may be classified as bull or heifer. Cow is female after first calf: bull is entire male over 2 years old. Castrated males: steer calf to 1 year, steer or bullock—over 1 year, stag—adult, castrated when mature.
Lamb, birth to weaning (average 4 months), weaner—4 months to 2-tooth. 2-tooth to 15 months. 4-tooth to 2 years. 6-tooth to 3 years. Full mouth to 4 years. All groups may be subdivided into ram and ewe groups. Females are ewe lambs, 2-tooth ewes, etc. Ewes at first lambing. Gimmer is ewe that has not borne a lamb. Adult entire males are rams or tups. Castrated males are wethers or hoggets or hoggs; these may also be subdivided into age groups, e.g. 2-tooth hoggets.
Piglet—birth to undetermined period, probably synonymous with suckler. Suckler—birth to weaning. Weaner—after weaning to attainment of approximately 30 kg, or 65 pounds, bodyweight. Boar—entire male over 6 months old, usually for breeding but not necessarily so. Maiden gilt—female in the breeding herd, over 6 months old but not yet mated. Gilt—female in breeding herd but not yet farrowed for first time. Sow—female that has farrowed. First litter sow—from first fertile mating to second. Barrow—castrated male in fattening herd.
Foal—birth to one year, filly or colt foal. Yearling—1 to 2 years, filly or colt. Then, 2 year old, 3 year old and so on. Filly—under 4 years. Mare—4 years and over. Then, classified on a use basis—e.g. brood mare. Colt—2 to 4 years. Stallion—entire male 4 years and over. Gelding—castrated male any age.
Show classes for pups have different age limits in different places. Males and females graduate from puppydom at sexual maturity when about 6 months old.
Kittens until sexual maturity at 5 to 6 months for females, slightly older for males.
Chicken, hatching to 4 weeks. Pullet—4 weeks to 5 months. Cockerel—4 weeks to 5 months. Rooster and hen—over 5 months. Turkeys—as for fowls except that young birds are poults and adult males are toms. Ducks similarly, with young birds called ducklings, the adult females are ducks and the males are drakes. In all species the dividing line between adult and young birds is not age but sexual maturity as evidenced by commencing egg laying or, in the case of males, mating females.
References in periodicals archive ?
But, the difference between consecutive age classes was little, especially between age class III and IV, and IV and V.
Due to this limitation, past snail abundance records by age classes were analyzed to establish the seasonality of reproductive and recruitment of P.
A combination of length and width distinguished age classes in Manipur brow-antlered deer Cervus eldi eldi (Khan and Goyal 1993) and Svalbard reindeer Rangifer tarandus platyrhynchus (Morden et al.
Between 1980-1987 and 2005-2009, a 4-10% increase in mean body weight occurred in the youngest 4 age classes (1.
She said because of the make-up of the school, it is expected the school will not have mixed age classes but instead have three classes of 25.
Of these 440 individuals, we captured 127, 164, 106, 79, and 25 in age classes 1, 2, 3, 4, and 5, respectively.
The analysis of the back-calculated results indicated variation at different age classes among the studied populations (Fig.
Five age classes (AC) from juvenile (<1 y) to 4+ y were determined primarily from wear of the last upper molar (Fig.
The following is what to look for in various age classes of bucks to determine if it meets the minimums of wherever you may be hunting.