Two commercial cottonseed meals, a direct solvent-extracted meal and a screw-pressed meal, were subjected to successive solvent-extraction procedures by using an acetone/hexane/water azeotrope to reduce their cyclopropenoid fatty acid content. The two original commercial meals, as well as a double-and triple-extracted portion, were then incorporated at 20 wt % levels in the rations of laying hens. A negative control containing 25% soybean meal and a positive control containing 2 % refined cottonseed oil of known CPA content were also employed. During a fourweek feeding period the eggs were collected during the third and fourth week and stored at 35F for periods of three and six months. Overall egg quality and the fatty acid distribution of the extracted yolk lipids were determined after the three-and six-month storage period.

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Chemical inactivation of cyclopropenoid fatty acids in commercial cottonseed meals was explored with three classes of compounds : anhydrous gases, organic acids and sulfhydryl compounds. Of the reagents screened, sulfur dioxide reduced the cyclopropenoid content by over 90% while free cottonseed fatty acids and thioglycollic acid reduced the cyclopropenoid fatty acid content by over 30%. Large batches of the above three selected meals, as well as a control commercial screw-pressed meal, were then incorporated at 20 wt % levels in the rations of laying hens. A negative control containing 25% soybean meal and a positive control containing a 2% refined cottonseed oil of known CPA content were also employed. During a four-week feeding period, eggs were collected during the third and fourth week and stored at 35 F for periods of 3 and 6 months. Overall egg quality and the fatty acid distribution of the yolk lipids were determined after the 3 and 6 months' storage periods.

Summary Raw and pasteurized milk samples were plated by seven analysts using 0.1- and 1.0-ml quantities (of appropriate dilutions) dispensed by 0.1-ml glass, 1.1-ml plastic and 1.1- and 2.2-ml glass pipettes. Incubation was at 32 C for 48 hr. Data were subjected to an analysis of variance and the standard deviation as a ratio was calculated. The procedures were compared from two points of view, first to determine if biases existed between the different methods and second if the techniques differed in their random error. No appreciable differences were found between types of pipettes when pasteurized milk was plated. The quantity used, however, was important. Use of a 0.1-ml sample size was associated with more variable results which averaged 10% higher than when a 1.0-ml quantity was plated. Statistical analysis of test results obtained with pasteurized milk suggests: (a) when 0.1-ml samples were used least variation was encountered with the 0.1-ml glass pipette and most variation with the 1.1-ml glass pipette, and (b) when 1.0-ml samples were used very little difference appeared between pipettes although the 1.1-ml plastic pipette tended toward less variation. When raw milk contained large numbers of bacteria, the plastic pipette tended to give higher results than glass pipettes when the 1.0-ml quantity was used; however, these differences with raw milk were not found to be statistically significant. Standard deviations as a ratio revealed: (a) greatest variation with the 2.2-ml glass pipette and least with a 0.1-ml glass or 1.1-ml plastic pipette when a 0.1-ml quantity was used, and (b) greatest variation with a 1.1-ml plastic pipette and least with a 2.2-ml glass pipette when a 1.0-ml sample size was used.

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