Cottonseed meal

Cottonseed meal is the byproduct remaining after cotton is ginned and the seeds crushed and the oil extracted. The remaining meal is usually used for animal feed and in organic fertilizers. However, the meal can be fed only to adult ruminants because it contains a compound called gossypol. The compound is highly toxic to monogastrics and even sometimes to calves which have less well-developed digestive systems.

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Wikipedia