ABSTRACTS
Selecting dairy cattle. W. B. NEVENS AND A. F. KUHLMAN (1938) Illinois,
Agr. Exp. Sta. Cir. 486.
C ONSTANT improvement in the quality of a herd is every breeder's goal. Ability
to judge good type and interpret production records and pedigrees is therefore
essential. Lack of this ability causes disappointment to the man purchasing animals
as well as to the man selecting animals from his own herd for breeding purposes. Such
ability comes only after years of experience. The sooner such experience is acquired
the better.
Pure-bred breeders selling breeding stock must know what others think are the
accepted types. Pedigrees, blood lines and families should be familiar to him. Such
knowledge, plus the ability to recognize how closely his own cattle approach this ideal
(accepted type), is the only means by which he can supply the animals desired by the
purchaser.
Dairy animals are generally selected alone on their type or the fact that they are
from excellent dams. Selection should always be made on the basis of both these
considerations. The animal's own production record, if any, and those of its nearest
relatives should be included. Breeders should be satisfied with no less—including a
wide experience in such selecting. A breeding dairy animal serves two purposes : milk
production, and reproduction. Certain physical characteristics contribute to greater
efficiency in each and can be detected by a good breeder with the help of production
records. Such records, however, are the most reliable basis for selection.
Production records and -pedigrees.—Production records are of several kinds : private,
dairy herd improvement association or official. Pedigree records may be private or
those of a herd book or breed association. Private records are only as reliable as the
person keeping them, whereas other records, being kept cooperatively, in a sense are
very reliable. To supplement such information on production other things must be
known ; age of the cow, numbers of daily milkings, quality and quantity of feed, care
and management, interval between calves and dry period. Feed, care and calving
interval are most responsible for variations in the production of animals of equal ability.
Animals calving at two, three, four, and five years of age generally produce in the first
lactation about 77, 87, 94, and 98 per cent as much milk in the first lactation respectively,
as they will at seven years of age, after which production starts to decline. The butter
fat test of the milk makes the production picture more complete and aids in further
selection.
Such records give information on three points, viz. productive capacity, transmit-
ting ability and longevity. The individual's record gives information direct on the first
and the last. Records of daughters, son's daughters, sisters, etc., give the second
in a complete form.
Many animals milk well, but do not produce progeny
having this quality. Longevity is important in the total life time production and number
of progeny. To be ' proved ' an animal must produce progeny which are as good or
better producers than the parent. This takes time, but is valuable indeed. Especially
is this true of a sire—a ' proved' sire has at least five daughters whose production re-
cords are known—since his progeny number many more than in the case of one female.
The most reliable method of choosing a herd sire that will be likely to get daughters
having capacity for high production of milk and butter fat is to select one that is already
the sire of such daughters
the next best procedure is to obtain one that has a dam and
sisters with records of high production '.
Dairy Type.—On the basis of type, mature cows, heifers and bulls should be consi-
dered separately. Milk production involves the conversion of energy from one form into
another—from feed into milk. This conversion involves work. Characteristics, therefore,
which suggest high feed capacity, good circulation, large lung capacity and well developed
milk producing organs give evidence of a high capacity for work and therefore milk pro-
duction. Type, as used with reference to dairy cows, involves the greatest possible
development in respect to these characters. A few weeks after a cow freshens is, there-
fore, the best time to judge her for type, since she is then at her highest level of
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