White ' Diarrhea 285 



with weak constitutions, easily overcome by disease germs. 

 Without doubt the points at which most progress can be 

 made in combating such diseases are in the methods of in- 

 cubation and in the care of the chicks for the first three weeks 

 of their lives. Nevertheless it should not be forgotten that 

 the death of the chick is caused by the ravages of some mi- 

 nute parasitic organism. 



Within recent years several investigators have discovered 

 organisms which they believe to be the specific cause of 

 white diarrhea. Three of these may be mentioned at this 

 place : (1) Coccidium tenellum or cuniculi producing the 

 disease called "coccidiosis." (2) Bacterium pullorum pro- 

 ducing "bacillary white diarrhea" and (3) Aspergillus 

 fumigatv^ and allied species, producing aspergillosis or 

 brooder pneumonia of chicks. Of these the first two dis- 

 eases will be considered in some detail in the following 

 paragraphs. Aspergillosis is treated in a separate section 

 of this chapter (cf. p. 173). 



Intestinal Coccidiosis 



In 1908 Morse ' published a preliminary account of some 

 investigations on the cause of white ■ diarrhea. He claimed 

 that microscopic examination of the intestines of chicks 

 dying with this disease revealed the presence of large num- 

 bers of protozoan organisms which he identified as Coccidium 

 tenellum. Cole and Hadley^ of the Rhode Island Experi- 

 ment Station reported finding a similar organism in white 

 diarrhea chicks. They identified it as Coccidium cuniculi. 

 These two species of coccidium are so nearly alike that it is 



1 Morse, G. B., "White Diarrhea of Chicks." U. S. Dept. of 

 Agr. Bur. Anim. Indus. Circ. 128, pp. 1-8, 1908. 



2 Cole, L. J., and Hadley, P. B., "Blackhead in Turkeys." 

 Rhode Island Agr. Expt. Stat. Bui. No. 141, pp. 138-272, 1910. 



