and Veterans Administration Hospital, Birmingham, Alabama Studies of nutrient and antibacterial properties of saliva require a saliva that is free of viable microorganisms. In the past, sterile saliva has been produced either by one of the methods used to sterilize bacteriologic media or by aseptic collection from the ducts of the salivary glands. The changes in salivary components caused by sterilization have been mentioned in very few reports. A number of investigators'-8 have characterized growth-inhibitory constituents of saliva as being heat-stable or heat-labile, filterable or non-filterable, and present in sediment or supernatant fluid. However, the emphasis was not on changes brought about in saliva by the process of sterilization. Jackson and Williams9 have sterilized whole saliva by the addition of ethylene oxide (0.6-2.0 per cent incubated with whole saliva for 18-24 hours at 370 C.) and reported that amylolytic activity was reduced by 20 per cent.Separate salivary secretions, which can be collected sterile or with few bacteria, lack some of the constituents of whole saliva. Parotid or submaxillary secretions obtained by aseptic cannulation have been used in studies of antibacterial factors'0 and of substances1' supporting the growth of bacteria. Submaxillary and sublingual secretions collected with the aid of a sterile Schneyer segregator were sterilized by brief exposure to 2537 A ultraviolet light.12' 13 This treatment did not significantly reduce their amylolytic activity.The present report deals with the application of 5 sterilization methods to whole saliva and with the effects of these procedures on some salivary components. The principal goal was reproducible sterility of saliva. In addition, the sterile saliva should have suffered a minimum loss of bacterial metabolites and host materials such as enzymes and plasma proteins. Sterile and unsterile saliva were compared for concentrations of amylase, catalase, and peroxidase. The effect of sterilization upon other proteins in saliva was determined by precipitin tests with specific antisera. Similar tests were also applied in evaluating the effects of various conditions of storage.Materials and Methods SALIVA.-Paraffin-stimulated saliva was collected from employees of a research laboratory and of a dental clinic. Samples were chilled immediately following collection. Food particles, paraffin, mammalian cells, and clumps of bacteria were removed by filtering through gauze or washed glass wool.* The saliva was pooled and stored in Erlenmeyer flasks at 40 C. for 1-2 hours before sterilization.

The stability of several medicinal additives in cattle, pig and poultry feeds has been monitored. The feeds were stored at various temperatures under different conditions; processes such as freeze-drying, gamma-irradiation and pelletization were also applied. The medicinal additives appeared to be more stable in the feeds stored at reduced temperatures and under conditions that totally exclude light. Processing of feeds and storage at elevated temperature appeared to reduce the content of the medicinal additives examined.

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