COMPARISON OF DIGESTIBILITY, NUTRITIVE-VALUE, AND STORAGE CHARACTERISTICS OF DIFFERENT FORMS OF COTTONSEED IN DIETS FED TO LACTATING DAIRY-COWS

Thirty-two Holstein cows averaging 70 d postpartum were used to compar e digestibility of whole short staple cottonseed (SS) to whole Pima (W P), coarsely cracked Pima (CrP), and ground Pima (GP) cottonseeds and their effects on lactational performance. Cottonseed was fed at 15% of diet DM. Milk and solids-corrected milk (SCM) yields were higher for cows fed GP than for cows fed CrP or WP but were not different from yi elds of cows fed SS. Feed efficiency (SCM/DMI) was higher for cows fed GP and SS than for those fed WP. Milk of cows fed GP was lower in ste aric acid but higher in linoleic and linolenic acids than milk of cows fed SS. Whole seeds passing into the feces (percentage of consumed) w ere higher for WP (12.3%) than for SS (6.2%). Total tract digestibilit y of ether extract was lower for WP than for other diets. Digestibilit ies of other nutrients were not different. To test storage characteris tics, samples of cottonseed were incubated at 32-degrees-C and 30% rel ative humidity for 0, 10, 20, and 30 d, or stored at ambient temperatu res in covered buckets for 9 mo. No differences in amount of free fatt y acids between incubated samples were noted, and only CrP stored in b uckets for 9 mo was significantly higher in free fatty acids than init ial or frozen seed. No differences in aflatoxin were detected, and lev els were very low. Milk yield of cows fed GP diets was similar to that of cows fed SS diets and slightly higher than those of cows fed CrP o r WP diets. Processing the Pima seed increased feed efficiency.