May, 1939] Protein Requirements of Chickens . 5 



varieties of fish but consisted largely of cod and haddock. The raw 

 product was ground, cooked and pressed previous to being placed into the 

 dehydrator. The product was dehydrated at a 26"-27" vacuum at an 

 inside temperature of approximately 120° Fahrenheit. 



During the course of the 140 weeks of actual test time, it was necessary 

 to secure more than one lot of protein concentrate. The successive lots 

 used, however, were of the same brand and were made under as identical 

 conditions as possible. The variation in protein content is shown in 

 Table I. 



Test I — Discussion 

 Starting Period (0-12 Weeks) 



In this study experiments have been limited to three animal protein 

 sources; namely, meat scrap, fish meal, and dried skimmilk. In Table 

 III, showing a summary of weight records for the respective groups, it is 

 interesting to note that in all protein groups as the percentage content 

 increased, so did the weight. The group receiving 15 per cent dried 

 skimmilk was the lowest in weight at 2.293 pounds per chick. Group 12 

 receiving 19 per cent protein from all three animal sources averaged the 

 greatest weight at 2.961 pounds per chick. These results are in harmony 

 with previous work at this station indicating that protein levels of from 

 18-20 per cent during the first 12-week period produce the greatest gains 

 in weight. 



Summarizing results by groups according to type of animal protein 

 concentrate received, we find the mixture groups (10, 11, and 12) leading 

 with an average weight per chick of 2.855 pounds. The fish meal, meat 

 scrap and dried skimmilk groups follow in the order named. Only very 

 slight differences of little significance are apparent. No significant dif- 

 ferences occur among groups insofar as feed consumption per bird is con- 

 Table Ill-a. Summary of weight records in pounds per bird bj^ stated 

 weekly periods for meat scrap groups 



Age Group 1 Group 2 Group 3 

 Test 1 Test 2 Test 1 Test 2 Test 1 Test 2 



1 Dav 0916 



4 Weeks 4617 



8 " 1.392 



12 " 2.448 



16 " 2.903 



19 " 3.593 



23 " 4.272 



27 " 4.805 



31 " 4.853 



35 " 4.995 



39 " 5.005 



43 " 5.035 



47 " 5.047 



51 " 5.153 



55 " 5.217 



59 " 5.155 



63 " 5.176 



67 " 5.210 



70 " 5.256 



