122 MAINE AGRICULTURAL EXPERIMENT STATION. I914. 

 3. VARIATION RELATED TO THE STATE OF HEALTH. 



One of the birds (No. 441) used in this investigation offers 

 an opportunity to study the effect of the state of health upon the 

 weight of the egg. This bird laid 179 eggs during her pullet 

 year. These eggs increased in size exactly in accordance with 

 the general rule for the flock. Her body weight increased from 

 2003 gms. in November and December 19 10 to 2325 gms. in 

 September, 191 1. That is up to the first fall month she was a 

 normal bird. She stopped laying for the molt October 17, 1911, 

 and did not lay again until March 4, 1912. From this time 

 until August 17 she laid quite well for a second year Barred 

 Plymouth Rock, producing 90 eggs in this time. These eggs 

 were smaller than the eggs of the previous year. Nothing ab- 

 normal w^as seen in the appearance of the bird until during the 

 summer when she began to appear somewhat sick. She con- 

 tinued to lay until August 17. After this she became more 

 dumpish. In September it was apparent that she would not 

 recover and lay before the close of the investigation in Novem- 

 ber. She was therefore, killed and autopsied September 10, 

 1912. 



At autopsy her body weight was 2190 gms., a slight decrease 

 from the weight a year before. The following lesions were 

 recorded: i. The liver was congested and friable. 2. The 

 lungs were congested and showed yellowish lesions. 3. There 

 was some peritoneal disturbance which had caused a greenish 

 deposit on the intestinal mesentery. That is the bird at autopsy 

 showed evidences of disturbances which were probably of some 

 time standing. 



A comparison of the egg data for this bird with the cor- 

 responding data for the other birds show that during the first 

 year each egg part increased in weight in the normal manner. 

 The bird was then no doubt in good physical condition. The 

 bird did not lay from October, 19 11 to March, 1912. Through- 

 out the second year the weight of each egg part decreased. -This 

 decrease was most rapid after the bird was observed to be sick 

 but had been going on for three months before this. Evidently 

 the physiological disturbances had affected the size of the egg 

 before they affected the behavior of the bird. 



Five other birds died or were killed during the investigation. 



