An isopropanol (IPA)-extracted cottonseed meal (CSM) was evaluated in comparison with a regular CSM and soybean meal over 12 months with laying hens. Each CSM was fed at 5, 10, and 15% of the diet. Egg production rates comparable to those of birds fed the soybean meal basal diet were obtained with both meals at dietary levels up to 15%. Egg weight was significantly reduced by all regular CSM treatments, but IPA-CSM had no effect on egg weight in comparison with the basal diet. Egg mass (grams of egg/hen per day) was not adversely affected by either CSM.Even though the nitrogen solubility index (NSI) of IPA-CSM (12.88%) was considerably lower than that of regular CSM (51.15%), true lysine availabilities were 87.3% for IPA-CSM and 83.2% for CSM. True dry matter digestibilities (77.9% for IPA-CSM and 73.6% for regular CSM) also suggest that the NSI method underestimated the nutritive value of IPA-CSM.True metabolizable energy content of IPA-CSM determined with laying hens was 3.12 kcal/g and slightly higher than the 2.76 kcal/g determined for regular CSM.Neither CSM produced objectionable yolk discolorations upon storage (56 days at 7.2 C). Although slightly discolored yolks appeared in 28.2% of stored eggs from hens fed 15% regular CSM (101.5 ppm free gossypol) and only 2.6% occurred when 15% IPA-CSM added 3.0 ppm free gossypol to the diet, these were scored less than 2 and would not be objectionable in commerical channels.The proportion of yolk saturated fatty acids increased significantly with 15% regular CSM (.105% dietary residual oil) from 28.6% for the basal diet to 44.0%; whereas 15% IPA-CSM, supplying .023% residual oil, resulted in a nonsignificant increase to 35.1%. (Key words: cottonseed meal, interior egg quality, gossypol, and laying hens)

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