INSPECTION OF COMMERCIAL FEEDSTUFFS 



By Feed Control Service Staff: 



John W. Kuzmeski, Research Professor, Official Chemist 



Albert F. Spelman, Associate Research Professor 



C. Tyson Smith, Assistant Research Professor, Microscopisi 



Robert T. Wetherbee, Assistant Research Professor 



Joseph Bart, Research Instructor 



Joseph A. Martell, Technical Assistant 



W. Noel Jameson, Technical Assistant 



Joseph Conklin, Inspector 



Cora B. Grover, Principal Clerk 



This bulletin presents analytical data on official feed samples received at this 

 laboratory during the 1948-1949 season. These data show that conformity to 

 guaranteed analj'sis was better than it has been for some years. 



For the first time since 1941 results of vitamin D assays on a number of fish 

 liver oils and dry poultry/ vitamin D supplements are reported. It is planned to 

 continue anc expand this work as a regular part of the Feed Control Service. 



Collaborative work is being done on methods for the determination of iodine, 

 cobalt, copper, and vitamin A in mixed feeds. It is hoped, particularly, that 

 workable method for vitamin A determination in mixed feeds can be adapted to 

 routine control work. There is an urgent need for such a method. 



Considerable time was spent on a method for the determination of tocopherol 

 or vitamin E. The results obtained are not favorable. Possibly modification of 

 existing methods or development of new ones may lead to better results. A good 

 tocopherol method would be very useful in cases of suspected vitamin E deficiency 

 in the feed as the cause of so-called "crazy chick" disease. 



The use of sulfaguanidine and sulfaquinoxaline in starter and broiler mashes 

 has necessitated analytical work for the determination of these drugs. For- 

 tunately, there are com.paratively simple methods for the determination of these 

 ingredients. 



One of the newest problems confronting control officials is that of a satis- 

 factory procedure for control purposes for the determination ot vitamin B12, also 

 called the Animal Protein Factor. Supplements have been registered and are 

 being sold in many states with claims for high animal protein factor potency. 

 The control official, as in the case of other claims, should be able to either sub- 

 stantiate or refute such claims. 



In addition to the analytical work reported in this bulletin, the Feed Control 

 Service analyzes manj' samples representing lots of feed delivered to the various 

 State institutions. As a result of this work these institutions are now receiving 

 better quality feed than was formerly the case. It is planned to extend this 

 service to cover the feed delivered to each one of the 28 State institutions buying 

 feed. 



Many samples are analyzed, also, for individuals: including feed suspected 

 of containing toxic ingredients; feed unfamiliar to the individual, who would like 

 to know its feeding value; and feed thought to be not as guaranteed. A few 

 samples of stomach contents and viscera of animals believed to have died of 

 poisoning are received each year. If the circumstances warrant such action, a 

 limited chemical examination is made in these cases. 



A great deal of analytical work is done on feeds and other materials on re- 

 search projects in which the Feed Control Service cooperates with the other 

 Experiment Station departments originating the research projects. 



