Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 52-57). Also available on the World Wide Web.

Broilers are raised indoors on high density farms with bedding/litter to trap their manure. Ammonia gas, which is produced as the manure decomposes, has adverse effects on human health, bird welfare and the environment. Using litter amendments can reduce the amount and, consequently, the effects of ammonia emitted from broiler houses. The objective of this study was to determine the effectiveness of a biodegradable litter amendment (BLA) in reducing ammonia emitted from a broiler house. A pilot scale test was set up with six adjacent, individually ventilated rooms and a stocking density of 0.07 m² per bird. The birds were fed with a standard commercial, corn and soybean meal based diet and water was provided ad libitum. The first flock was grown on 10 cm of fresh, kiln-dried pine shavings, while subsequent flocks were grown on top-dressed reused litter. The two treatments (control (CTL) and BLA) were randomly assigned to the six rooms after flock 1, to give three replicates per treatment. The exhaust air from the rooms was sampled for ammonia concentration for two days each week starting at four days of age to determine the amount of ammonia emitted. Over three subsequent flocks, the total mass of ammonia emitted from rooms treated with BLA was 31% to 47% lower than the control. Ammonia emitted per bird grown on treated litter and per kg of harvested bird weight was 32% to 44% lower, and the exhaust fans ran 7% to 22% less than CTL over the same period. For both BLA and CTL, the amount of ammonia emitted generally increased with bird age and litter reuse. The study showed that BLA effectively reduced ammonia emitted from a broiler house and that there are potential energy savings from using the amendment. However, ammonia emitted from the BLA rooms during the final flock was 57% higher than CTL, which was attributed to insufficient water (less than 18% moisture by weight) to support the reaction between BLA and ammonia. / Ph. D.

Nutrient cycles and budgets have been calculated for various ecosystems, but the impact of floral and bark litter decomposition on nutrient cycling has been little investigated. In this study, the characteristics and decomposition of floral and bark litter produced by Nothofagus fusca in the Lewis Pass Reserve, New Zealand, was investigated, using both field and laboratory studies. Nothofagus fusca floral litter production in 1999 was 734 ± 76 kg ha⁻¹. Floral production in 2000 was estimated to be approximately 1% of this mass, the considerable difference being due to mast flowering in 1999. The decay rate constant, k, for floral litter in the field was 0.94 ± 0.01, and mass loss after one year was estimated to be 61%. The input of nitrogen to the litter layer in Nothofagus fusca floral litter was 12 ± 1 kg ha⁻¹, and it was estimated that 65% of this nitrogen was released from the floral litter in the one year. Phosphorous input to the litter layer through Nothofagus fusca floral litter in 1999 was 0.8 ± 0.1 kg ha⁻¹, of which 69% was released in one year. It was estimated that in 1999 nitrogen and phosphorous inputs to the litter layer through Nothofagus fusca floral litter were 117% and 73% respectively of that through foliar litter. Four types of Nothofagus fusca bark were identified and further differences between bark types were confirmed by chemical analysis. Inner bark contained less nitrogen than outer bark, and was slower to decompose in microcosms, contradicting the findings of other research. Annual nitrogen and phosphorous inputs through the production of all types of Nothofagus fusca bark litter was estimated to be 1.0 kg ha⁻¹ and 0.2 kg ha⁻¹ respectively, although confidence in these values was low. Significant proportions of the nitrogen and phosphorous content in bark were water soluble. Field and laboratory experiments indicated net nitrogen immobilisation occurred in all bark litter types after one year in the field, while net release of phosphorous occurred after one year.

No description available.

Cheng Suet Ha. / Bibliography: leaves 179-195. / Thesis (M.Phil.)--Chinese University of Hong Kong.

The reuse of litter in broiler production can lead to litter pathogen buildup and high levels of ammonia in broiler housing, thus resulting in poor broiler performance. This study evaluated the effects of two microbial litter amendments on litter characteristics, ammonia production and broiler performance. Experiment one, consisting of three trials, utilized eight pens approximately 3 x 3.2 m (10 x 10.5 ft) to rear broilers to 49 d of age. Experiment two, consisting of one trial, utilized twelve 1.8 x 3.7 m (6 x 12 ft) pens to rear broilers to 42 d of age. Used litter was obtained from separate commercial broiler farms for each experiment and placed into the pens at an average depth of 11 cm (4.3 in). Feed consumption and mortality were recorded for each pen for each trial. Ammonia production was measured by placing an enclosed chamber over the litter and measuring the headspace ammonia concentration after 20 minutes for both experiments. Experiment one also utilized a two minute ammonia flux technique. Ammonia measurements were taken at the time of litter treatment, at chick placement, and once per week for the remainder of the grow-out. Litter samples were collected at the same time and location as ammonia measurements. At the end of all trials, caked litter was removed from each pen, weighed and sampled. Litter and cake samples were analyzed for total aerobic and anaerobic microbial counts in experiment 1. Experiment 2 analyzed aerobic litter samples only. Paw scores were also recorded at the end of each trial for all birds using a 3-point scale. Data was subjected to ANOVA using the GLM procedure with means deemed significantly different at P < 0.05. Statistical differences were seen sparingly in different parameters in both experiments; however these differences were random in their distribution and showed no trend. Final results indicated that the microbial litter amendments had no effect on broiler performance, litter characteristics or ammonia production.

No description available.

No description available.

Nutrient cycles and budgets have been calculated for various ecosystems, but the impact of floral and bark litter decomposition on nutrient cycling has been little investigated. In this study, the characteristics and decomposition of floral and bark litter produced by Nothofagus fusca in the Lewis Pass Reserve, New Zealand, was investigated, using both field and laboratory studies. Nothofagus fusca floral litter production in 1999 was 734 ± 76 kg ha⁻¹. Floral production in 2000 was estimated to be approximately 1% of this mass, the considerable difference being due to mast flowering in 1999. The decay rate constant, k, for floral litter in the field was 0.94 ± 0.01, and mass loss after one year was estimated to be 61%. The input of nitrogen to the litter layer in Nothofagus fusca floral litter was 12 ± 1 kg ha⁻¹, and it was estimated that 65% of this nitrogen was released from the floral litter in the one year. Phosphorous input to the litter layer through Nothofagus fusca floral litter in 1999 was 0.8 ± 0.1 kg ha⁻¹, of which 69% was released in one year. It was estimated that in 1999 nitrogen and phosphorous inputs to the litter layer through Nothofagus fusca floral litter were 117% and 73% respectively of that through foliar litter. Four types of Nothofagus fusca bark were identified and further differences between bark types were confirmed by chemical analysis. Inner bark contained less nitrogen than outer bark, and was slower to decompose in microcosms, contradicting the findings of other research. Annual nitrogen and phosphorous inputs through the production of all types of Nothofagus fusca bark litter was estimated to be 1.0 kg ha⁻¹ and 0.2 kg ha⁻¹ respectively, although confidence in these values was low. Significant proportions of the nitrogen and phosphorous content in bark were water soluble. Field and laboratory experiments indicated net nitrogen immobilisation occurred in all bark litter types after one year in the field, while net release of phosphorous occurred after one year.

Thesis (M.A.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 28-32). Also available via Humboldt Digital Scholar.