70 



THE REPORT OF THE 



No. 33 



chicks and allowing the lice to transfer naturally to the fluff of the head. In 

 addition to this, two infected birds were placed under the hover at night and 

 removed the next morning. 



The following table illustrates the comparative results, viz., the weekly 

 weights, feed consumed, etc.: 



Infected Pen No. 

 Chicks hatched July 30, 1922. 

 Infected Aug. 12 — 14 days old. 



of Aug. I2-IQ 

 Number of birds living, 15. 

 Total weight, Aug. 12, 1 lb. 8 oz. 

 Total weight, Aug. 19, 2 lb. 12 oz. 

 Total gain for week, 1 lb. 4 oz. 

 Average gain per bird, 1.33 oz. 

 Feed consumed "Mash," / lb. 

 Mortality, nil. 



Week of Aug. ig-26 

 Number of birds living, 13. 

 Total weight, Aug. 19, 2 lb. 12 oz. 

 Total weight, Aug. 26, 3 lb. 15 oz. 

 Total gain for week, I lb. 3 oz. 

 Average gain per bird, 1.46 oz. 

 Feed consumed "Mash," 103^ lb. 

 Mortality, 2 birds. 

 1 died Aug. 23, 1 died Aug. 24. 



Week of Aug. 26— Sept. 

 Number of birds living, 13 

 Total weight Aug. 26, 3 lb. 15 oz. 

 Total weight Sept. 3, 5 lb. 2 oz. 

 Total gain for week, 1 lb. 3 oz. 

 Average gain per bird, 1.46 oz. 

 Feed consumed "Mash," 12 lbs. 

 Mortality, nil. 



Week of Sept. 3-10 

 Number of birds living, 12. 

 Total weight Sept. 3, 5 lb. 2 oz. 

 Total weight Sept. 10, 6 lb. 2 oz. 

 Total gain for week, 1 lb. 

 Average gain per bird, 1.33 oz. 

 Feed consumed "Mash," 10^ lb. 

 Mortality, 1 chick died on Sept. 8. 



Control Pen No. 2 

 Chicks infected July 30 — 14 days old. 



Week of Aug. 12-iQ 

 Number of birds living, 15. 

 Total weight, Aug. 12, 1 lb. 6 oz. 

 Total weight, Aug. 19, 2 lb. 2 oz. 

 Total gain for week, 1 lb. 2 oz. 

 Average gain per bird, 1.2 oz. 

 Feed consumed "Mash," 6 lb. 

 Mortality, nil. 



Week of Aug. IQ-26 

 Number of birds living, 14. 

 Total weight, Aug. 19, 2 lb. 8 oz. 

 Total weight, Aug. 26, 3 lb. 12 oz. 

 Total gain for week, 1. lb. 4 oz. 

 Average gain per bird, 1.42 oz. 

 Feed consumed "Mash," 9J4 lb. 

 Mortality, 1 bird killed by rats on August 

 25. 



Week of A tig. 26 — Sept. 3 

 Number of birds living, 14. 

 Total weight Aug. 26, 3 lb. 12 oz. 

 Total weight Sept. 3, 4 lb. 13 oz. 

 Total gain for week, 1 lb. 1 oz. 

 Average gain per bird, 1.21 oz. 

 Feed consumed "Mash," 10.8 lb. 

 Mortality, nil. 



Week of Sept. 3-10. 

 Number of birds living, 13. 

 Total weight Sept. 3, 4 lb. 13 oz. 

 Total weight Sept. 10, 6 lb. 

 Total gain for week, 1 lb. 3 oz. 

 Average gain per bird, 1.46 oz. 

 Feed consumed "Mash," 12 lb. 

 Mortality, 1 bird died on Sept. 3. 



When the weighings were discontinued on September 18th, 1922, the total 

 aggregate weight of the twenty-five birds was found to be 12 lbs. 8 ounces, or 

 an average weight per bird of 8 ounces. 



Upon summarizing these results it will be noted that there was very little 

 to choose between the infected and control pens, the average gain and mortality 

 rate being about equal. 



Paradoxical as it may seem, the chicks in the infected pen at the end of the 

 experiment appeared to the casual observer to be more virile and in better 

 condition than the birds in the control pen. 



A second experiment was started on September 27th, 1922, fifty chicks being 

 selected for the purpose. 



These chicks were picked from a flock numbering about 300 birds, all of 

 which were two weeks of age and were selected for virility, etc. Twenty-five 

 chicks were used for a control pen and twenty-five were infected, from six to ten 

 adult lice being placed upon each bird. 



