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At present, demands for inexpensive and alternative protein sources for animal protein, in order to be used in value–added foods have been increased. Therefore, many researchers shifting on production of plant protein resources. So, the objective of present study was possibility measurements of cottonseed protein concentrate production for human consumption from cottonseed meal. Three different methods, n-butanol : acid, mixed solvents (water : acetone : hexan) and ethanol-ultra filtration, in order to produce cottonseed protein concentrate were examined. Variables (percentage) were nitrogen, nitrogen solubility, fat, crude fiber, total gossypol and free gossypol. Statistical analysis was performed in the three distinct statistical patterns and by using blocks completely random and examination at significantly = α 0.01. After comparing resulted data with world standard measurements, results obtained as follow: extraction methods with n-butanol : acid (9 times washing along with Hcl), using mixed solvents (30 : 67 : 3 ratio along with classic extraction) and ethanol-ultra filtration (alkaline extraction along with ultra filtration molecular weight Cut off: 20000) were suitable. The last extraction method was demonstrated as most appropriate method to produce cottonseed protein concentrate.

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An experiment was conducted to reevaluate the digestible lysine requirement of Arian male broilers by comparing the performance of chicks fed different levels of cottonseed meal (CSM) on a total amino acid (AA) versus a digestible AA basis. Four hundred and thirty two (432) Arian male broiler chicks were allotted to 18 treatments with four repli-cates of six chicks each in a completely randomized block design in a factorial arrange-ment with two factors (two levels of digestible lysine  nine different diets). The first of the eighteen treatments was the corn and soybean meal control diet based on previously de-termined digestible lysine requirement for maximum body weight gain. Diets 2 to 5 con-tained 5, 10, 15 or 20% CSM, respectively and were formulated to contain levels of total AA equivalent to those in the first treatment. Diets 6 to 9 contained the same levels of CSM as diets 2 to 5 but the diets were formulated to be equal in digestible AA content to the first treatment. Treatments 10 to 18 were the same as treatments 1 to 9, but on the ba-sis of determined digestible lysine requirement for maximum feed efficiency. Formulating diets containing CSM on a digestible AA basis resulted in an improvement in chick per-formance compared to those formulated on a total AA basis (P<0.01). The lessening of chick performance with diets formulated on a total AA basis compared to a digestible AA basis, indicated that the previously determined digestible lysine requirement for the Arian broiler strain may be correct.

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The aim of this study was to evaluate the effects of adding cottonseed meal along with the yeast Saccharomyces cerevisiae strain PTCC5052—either iron-enriched or non-enriched—on the economic justification of production, biochemical blood characteristics, microbial flora, and histopathological status of the intestine in juvenile rainbow trout. Fish were distributed in four treatments with four replications. One control diet without cottonseed meal, one diet containing 15% cottonseed meal, and two diets containing 15% cottonseed meal + 1 × 10⁸ cfu/g of yeast or iron-enriched yeast were provided to the fish for 8 weeks. The results indicated no significant differences in fish production efficiency, plasma biochemical indices, and histopathological status of the intestine among the treatments. The cost of feed per unit of fish production in the treatments containing cottonseed meal significantly decreased compared to the control treatment, with the lowest cost was observed in the treatment without yeast. No significant differences in microbial abundance were observed between the control treatment and the cottonseed meal treatment; however, the addition of yeast or iron-enriched yeast to the diet resulted in an increased density of the genus Saccharomyces, a reduction in the density of the genera Aeromonas and Vibrio, and a decrease in the density of Yersinia ruckeri in the fish intestine. The results of this study indicate that adding 15% cottonseed meal to the diet of rainbow trout can enhance the economic justification for fish production, and the addition of yeast to this diet improves the microbial flora in the fish's intestine