AVAILABILITY, STORAGE, TREATMENT, COMPOSITION, AND FEEDING VALUE OF SURPLUS COLOSTRUM - REVIEW

Bovine colostrum imparts passive immunity to newborn calves during the first 24 h of life and generally has been fed for the first 3 days after birth. Surplus colostrum is unmarketable and available in quantities sufficient to feed heifer calves through 28 to 35 days of age. Colostrum can be preserved conveniently for future use by brief refrigeration, freezing, or storage at ambient temperatures (fermentation or chemical treatment). Freezing results in virtually no loss of nutrients during storage but requires a freezer, extra handling, and daily thawing of required colostrum. Storage via fermentation or chemical treatment results in changes in physical characteristics, unavoidable nutrient losses, and occasional acceptability problems but is convenient and economical. Chemical preservatives are recommended for storage at warm temperatures. During storage at ambient temperatures, pH decreases as acidity increases, and total solids, protein, fat, and lactose contents of colostrum decrease. Total microbial numbers increase rapidly with initiation of fermentation, then level off or decline. Mold and yeast numbers continue to rise throughout storage. Some chemical additives are effective in stopping coliform growth or limiting mold and yeast growth. Colostrum can replace more than an equal weight of whole milk in calf-feeding programs due to its higher solids content. When colostrum is fed on an equal solids basis with whole milk, differences in calf performance are minimal. Colostrum generally does not cause scouring problems in calves. Maximal use of colostrum in calf-feeding programs is recommended. © 1978, American Dairy Science Association. All rights reserved.