The bird as an experimental animal.

For those who are not familiar with birds as experimental animals perhaps it should be pointed out that they offer many advantages over mammals, although they are obviously not the ideal animal for certain experiments. Few laboratories work with birds other than poultry, but canaries and other cage birds are occasionally used when their special qualities are applicable, as in work with low concentrations of carbon monoxide, or on bird malaria. At the present time an interest is developing in the laboratory use of the quail (Wilson, Abbott & Abplanalp, 1961). Fertile chicken eggs, day-old chicks, growing and adult fowls form the main source of birds for laboratory work, although again there are times when other species, such as the duck or turkey, are specially valuable. For example, the duckling is the species most susceptible to the toxin of ‘X’ disease, a new malady which last year killed off nearly 200 ooo commercial turkeys and which has been shown to be associated with the use of particular batches of Brazilian and other groundnut meals in feeds. Bronze turkey poults exhibit deficiencies of lysine more obviously than other species, and they have a much higher requirement for many vitamins than the fowl and, therefore, are specially suited for such nutritional work. Poultry have many economic advantages : ( I ) They are freely available, by the dozen or the thousand on a year-round