208 ILLUSTRATED STOCK DOCTOR- 
a!4 the qualities of tlic excellent milking breeds possessed by countries m 
which the soil is fertile, the air moist, and the sky often cloudy ; but as 
the influence of climate, though very marked, takes effect only in the 
long run, the properties of the animals imported are maintained — though 
subject, doubtless, to gradual deterioration — during a period which varies 
with the precaution taken to preserve them ; and for several generations 
the descendants of a good imported breed give more milk than individuals 
belonging to a breed found on the spot, where hygienic circumstances 
are not favorable to milking properties. 
It is not to bo forgotten, moreover, that under the influence of 
particular circumstances, which it is sometimes impossible to call into 
existence, animals manifest properties which we cannot produce directly. 
This explains why it is often more advantageous to import qualities 
possessed by foreign stock than to try to develop them in native stock. 
As milking qualities are in a great measure dependent on structure and, 
temperament, which are more or less hereditary, descent exercises a, 
great influence. 
Heredity.- 
Tn each breed, therefore, we should choose' individuals belonging tc 
the best stocks, and the offspring of parents remarkable for their milk- 
ing qualities ; for it is certain that good milch cows produce others which 
resemble them. 
But it is especially necessary when selecting stock for the purpose of 
breeding milch cows, that particular care should be taken to select indi- 
viduals belonging to good families. A cow of a bad milking family, or 
even breed, may occasionally be an excellent milker, and more than this 
is not wanted when it is not meant to breed from her. The same cannot 
be said when breeding is intended, because there would he little chance 
of her transmitting the accidental or exceptional qualities possessed by 
her ; whereas the qualities forming the fixed and constant characters of 
the stock would almost to a certainty be transmitted to descendants. 
These remarks, -with regard to breed and parentage, apply to the selec-* 
tion of the bull, which, as experience demonstrates, acts like the cow ia 
transmitting the milking qualities which distinguish the breed and stock. 
Digestion. 
The digestive organs have a great influence on the exercise of all the 
functions, and particularly on the secretion of the milk-glands. A\ here 
the digestive organs are defective, good milch cows are rarely met with 
Good digestive organs are known by a belly of moueiule size, witQ 
