722 IOWA DEPARTMENT OP AGRICULTURE 



The greater the number of birds which are kept upon any farm 

 or plot of ground, and the more they are crowded together, the greater 

 is the danger from contagion and parasites, and the more important 

 are the measures for excluding, eradicating and preventing the develop- 

 ment of these causes of disease. 



HOW TO PREVENT DISEASE. 



It is very important to start right and begin the flock with birds 

 which are free from contagion and parasites, and to put such birds 

 upon ground which is likewise free from these causes of disease. 



The best way to accomplish this is to get eggs from a flock which has 

 shown no indications of contagious disease for at least a year; avoid 

 putting these eggs in packing such as chaff, oats or cut straw, which 

 may be musty or moldy; wipe the eggs with a cloth wet in 70 to 80 

 per cent alcohol, and hatch them in a new or thoroughly cleaned incu- 

 bator. The young chicks should be free from parasites and injurious 

 germs of all kinds, and, to keep them in this condition, they should be 

 put in new or clean brooders and permitted to run only upon ground 

 where poultry has not previously been kept or which has not been 

 used for poultry for several years. 



Sometimes these directions cannot be followed in all respects. If 

 all the available ground has been recently used for poultry, the fowls 

 should be removed from that part which is to be used for the new 

 flock, a good coating of freshly slaked lime should be applied to the en- 

 tire surface of the ground, and a few days later it should be plowed. It 

 may now be cultivated three or four times with intervals of a week and 

 finally sowed with oats, rye, or other grain. In a few months the 

 greater part of the germs will be destroyed, but it is best to leave the 

 ground unoccupied by fowls until a winter has passed, as the freezing 

 and thawing of fall and spring is more effective than either continued 

 cold or warm weather. 



If the eggs must be hatched under hens instead of in the incubator, 

 the problem of starting a clean flock is much more difficult. Hens are 

 liable to harbor parasitic worms in their intestines and to scatter the 

 eggs of these worms with their manure wherever they go. They gener- 

 ally have lice and mites hidden in their feathers, which pass to the 

 young chicks immediately after the latter are hatched; and they may 

 be the carriers of disease germs even when they appear perfectly healthy. 

 For these reasons the hens which are used for hatching should be se- 

 lected from a flock that is known to have been free from other diseases 

 than those caused by accidents for at least a year, and the individual 

 birds of which are lively, vigorous, free from lice and mites, and pro- 

 ducing a large number of eggs. 



The hens selected for hatching should bo well dusted with a good 

 lice powder before they are given a setting of eggs; their nests should 

 be perfectly clean and should be made with fresh, soft hay or straw; and 

 there should be a box of road dust, or sifted hard-coal ashes of similar 

 substance, under cover, where they can dust themselves whenever they 

 come from the nest. When the young chicks are taken from the mest 



