SPENT CELLULOSE CASINGS AS POTENTIAL FEED INGREDIENTS FOR RUMINANTS

Cellulose casings are used to contain and form meat and poultry emulsi ons during the smoking and cooking process. Casings then are stripped from the cooked product and traditionally disposed of in landfills. Be cause of the bulk of the spent cellulose casings (SCC), rapid composti ng technology may be used to reduce bulkiness. The following SCC were evaluated in vitro and in vivo: fibrous ground (FG), fibrous composted (FC), NOJAX(R) ground (NG), and NOJAX(R) composted (NC). In vitro dig estibility was determined by incubating SCC with mixed ruminal bacteri a for 0, 6, 12, 24, 36, 48, and 72 h. In vivo data were collected usin g four ruminally cannulated Holstein steers in a 4 x 4 Latin square de sign. Diets consisted of a 50:50 ratio of alfalfa hay-wheat middlings with 5% corn-steep liquor. Diets contained no SCC (CON) or 25% (DM bas is) of the FC, FG, or NC SCC substrate. Casings were high in structura l carbohydrate and salt content but low in CP, ether extract, and lign in concentrations. In vitro OM digestibility at 24 h was highest (P <. 05) for FC and lowest (P <.05) for NG; FG and NC were intermediate. Co mposting tended to reduce fiber content and increase digestion. In viv o intakes and digestibilities were not adversely affected by inclusion of SCC in the diet. Thus, SCC have the ability to partially replace m ore traditional forages, such as alfalfa hay and wheat middlings, in h igh-fiber diets for growing beef cattle. Limitations in the use of SCC as a partial replacement of traditional feedstuffs will likely be bec ause of high salt concentrations in the casings resulting from product brine chilling.