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When poultry manure is collected but cannot be analyzed immediately, a method for storing the manure is needed to ensure accurate subsequent analyses. This study has 3 objectives: (1) to investigate effects of 4 poultry manure sample preservation methods (refrigeration, freezing, acidification, and freeze-drying) on the compositional characteristics of poultry manure; (2) to determine compositional differences in fresh manure with manure samples at 1, 2, and 3 d of accumulation under bird cages; and (3) to assess the influence of 14-d freezing storage on the composition of manure when later exposed to 25 degrees C for 7 d as compared with fresh manure. All manure samples were collected from a layer house. Analyses performed on the manure samples included total Kjeldahl nitrogen, uric acid nitrogen, ammonia nitrogen, and urea nitrogen. In experiment 1, the storage methods most similar to fresh manure, in order of preference, were freezing, freeze-drying, acidification, and refrigeration. Thoroughly mixing manure samples and compressing them to 2 to 3 mm is important for the freezing and freeze-dried samples. In general, refrigeration was found unacceptable for nitrogen analyses. A significant effect (P < 0.0001) of time for refrigeration was found on uric acid nitrogen and ammonia nitrogen. In experiment 2, the total Kjeldahl nitrogen and uric acid nitrogen were significantly lower (P < 0.05) for 1, 2, and 3 d of accumulation compared with fresh manure. Manure after 1, 2, and 3 d of accumulation had similar nitrogen compositions. The results from experiment 3 show that nitrogen components from fresh manure samples and thawed samples from 14 d of freezing are similar at 7 d but high variability of nitrogen compositions during intermediate times from 0 to 7 d prevents the recommendation of freezing manure for use in subsequent experiments and warrants future experimentation. In conclusion, fresh poultry manure can be frozen for accurate subsequent nitrogen compositional analyses but this same frozen manure may not be a reliable substitute for fresh manure if a subsequent experiment is performed.

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Clostridium cellulolyticum is capable of producing glycosyl hydrolase enzymes as well as fermentation products including ethanol and acetate. In this study, the potential of using C. cellulolyticum for ethanol and volatile fatty acid production from straw and grape pomace was examined. For rice straw, the effects of alkaline pretreatment and substrate sterilization prior to fermentation on products yields were also investigated. Effects of alkaline pretreatment and necessity for subsequent washing were tested for two types of grape pomace. For rice straw, the highest ethanol yield was 0.16 g/gVS from the straw pretreated with 10% sodium hydroxide loading at 121°C for 1 hour. Sterilization of the straw prior to fermentation was found to be not significant for ethanol production. Sterilization appeared to decrease native acetogen populations in the rice straw, resulting in lower acetic acid yields. The highest ethanol yield from grape pomace was of 0.09 g/gVS from the pretreated pomace. Pomace type (red or white) and washing were found to be not significant. Ethanol yields by C. cellulolyticum were lower than those from yeast in a simultaneous saccharification and fermentation system, but overall conversion of cellulose and hemicellulose was high, between 68 and 79%.