282 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VI, III
British farmer has no control. Unless we have fundamental knowledge concern-
ing the inheritance of the characteristics of the lactation, we need not hope to be
able to keep pace with market fluctuations.
Pending adequate analysis of the problem, a continuance of existing selec-
tion methods (with the re-enforcement of the recent remarkable rediscovery
of the progeny test) is much to be desired and will, on the whole, give good results.
When, as is bound to happen, there is a popular reaction to the progeny test
—not because it has failed to give results, but becuase those results have not
been as great as the advocates of the test are now promising—than the science
of genetics will be able to make a further and definite contribution to the subject,
provided that the foundations for such work have been well and truly laid.
Furthermore, the productivity of our live stock depends upon the close
interrelation of the control of disease with nutrition and genetics. The Scottish
shorthorn was not the product of Amos Cruickshank of Sittyton. It was the
product of Cruickshank and turnips and straw—all three of them from Aber-
deenshire. Likewise, the Aberdeen-Angus was not the product of McCombie,
but of McCombie, turnips, straw, and oil-cake. As the biologists and farmers
of Aberdeenshire fully appreciate, the science of the nutrition of our live stock is
making great headway. But it cannot outstrip the genetic application. Im-
proved methods of feeding put new stresses on the machine that can only be met
by the adjustment of the hereditary constitutions of the animals. At present
we lack the basal knowledge necessary to effect such alterations which the future
will certainly demand.
Let me illustrate this. Hitherto the ' basal ration' has been a most
useful conception in the theory of feeding live stock. In Edinburgh, we have
two strains of pigs. For the one, the average consumption of meal, per lb. of
liveweight gain, is over 4 lb ; for the other, the economical pigs, it is only about
2½ lb. The same holds good for cattle, both for milk and beef. Thus, by geneti-
cal methods, the interior economy of an animal can be modified to suit nutritional
requirements.
Finally, to those critics of the genetical method for the improvement of our
dairy cattle, I would say : It is worthy of remark that the hereditary improve-
ment in the yield of our dairy cows has taken place in the post Mendelian era.
The fact that the breeding of live stock has, in part, been reduced to a science, has
clarified thought and put the practice of live stock improvement upon a logical
basis. Moreover, each new generation of breeders has no longer to disentangle
fact from fancy. The existence of the science enables the young breeder
to start at the place where his father left off. This is no mean achievement to
the credit of the science of genetics, for it must be remembered that, whereas,
the improvement of the hereditary qualities of crops rests safely in the hands
of a few skilled research workers, the improvement of our live stock rests with
the innumerable breeders of that live stock distributed throughout the world.