Transforming shrimp and crab waste into dairy heifer feed

• Main Author: Evers, Dale J.
• Other Authors: Carroll, Diane J.
• Language: en_US
• Published: 2012
• Subjects: Heifers > Feeding and feeds; Animal waste as feed; Dairy cattle > Feeding and feeds
• Online Access: http://hdl.handle.net/1957/35279

The goal of these experiments was to ensile combinations of shrimp or crab waste with perennial ryegrass straw and analyze it for silage quality and ruminal degradability. The rapid deterioration of seafood wastes required initial preservation prior to ensiling to minimize odor production and protein breakdown. Eight experiments were conducted to preserve, ensile and test the ruminal degradability of shrimp and crab waste. The first three experiments attempted to preserve crab waste with the addition of 0 to 15% molasses for 14 days or shrimp waste with molasses at 0 to 25% for 6 or 21 days. In all three experiments, the addition of molasses decreased crude protein, crude protein loss, and pH, and improved odors. Although a lactic acid fermentation began, the high pH and acetic and butyric acid concentrations indicate fermentation was not completed. The crude protein loss and odor production warrants a quicker method of preservation. In Experiments 4 and 5, shrimp or crab waste were combined with 6 levels of salt from 0 to 12.5% for 6 days. The addition of salt decreased crude protein percentage, crude protein loss and all volatile fatty acid concentrations while increasing the pH and improving the odors. The 7.5% salt-preserved shrimp and crab wastes had 29.9 and 30.7% crude protein, respectively. Experiments 6 and 7 ensiled the salt-preserved shrimp and crab waste with grass straw, molasses and an inoculant in 15 L mini-silos for 40 days. Shrimp waste was combined at 37, 47 or 52% dry matter while crab waste was combined at 43, 46 or 52% dry matter. Molasses at 0, 10, or 20% and an inoculant were added to both silages. The 47% dry matter, 20% molasses non-inoculated shrimp silage had the following analysis on a dry matter basis: crude protein, 16.1%, acid detergent fiber. 27.0%. acetic acid, 1.37%. butyric acid, .01%, lactic acid, 7.17%, and a pH of 7.0 and a good silage odor. The 46% dry matter, 10% molasses, inoculated crab silage had the following analysis on a dry matter basis: crude protein. 21.1%, acid detergent fiber, 19.6%, acetic acid, 1.68, butyric acid, .00%, lactic acid, 2.86% and a questionable odor score. In Experiment 8, the ruminal degradability of shrimp and crab waste and shrimp and crab silage were tested using two fistulated steers and sampled at nine time points ranging from 0 to 96 hr. Shrimp waste had a ruminally available DM%, CP%, ADF%, and %ADIN of 36.9, 43.0, 44.2, and 43.6% respectively. Crab waste had a ruminally available DM%, CP%, ADF%, and %ADIN of 38.9, 53.3, 41.0, and 33.0% respectively. Ensiling the shrimp and crab wastes improved the percentage of ruminally available DM and CP and lowered the percentage of ruminally available ADF and ADIN. This indicates that ensiling promotes the degradation of chitin and the release of nitrogen to the rumen. Effective preservation of shrimp and crab waste with salt and then adequate fermentation of the wastes with grass straw, molasses and inoculant has increased the ruminal degradability of the wastes and led to successful transformation of the waste into a dairy heifer feedstuff. === Graduation date: 1995