Campylobacter jejuni is the leading cause of human food-borne bacterial gastroenteritis. The C. jejuni genome sequence predicts a branched electron transport chain capable of utilizing multiple electron acceptors. Mutants were constructed by disrupting the coding regions of the respiratory enzymes nitrate reductase (napA::Cm), nitrite reductase (nrfA::Cm), dimethyl sulfoxide, and trimethylamine N-oxide reductase (termed Cj0264::Cm) and the two terminal oxidases, a cyanide-insensitive oxidase (cydA::Cm) and cbb3-type oxidase (ccoN::Cm). Each strain was characterized for the loss of the associated enzymatic function in vitro. The strains were then inoculated into 1-week-old chicks, and the cecal contents were assayed for the presence of C. jejuni 2 weeks postinoculation. cydA::Cm and Cj0264c::Cm strains colonized as well as the wild type; napA::Cm and nrfA::Cm strains colonized at levels significantly lower than the wild type. The ccoN::Cm strain was unable to colonize the chicken; no colonies were recovered at the end of the experiment. While there appears to be a role for anaerobic respiration in host colonization, oxygen is the most important respiratory acceptor for C. jejuni in the chicken cecum.

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This paper discusses materials used as bedding or litter for the rearing of broilers and turkeys in the U.S.A. The U.S. poultry industry has historically used pine shavings as the litter of choice for many years. Sawdust has replaced pine shavings in many areas, however, not by choice, but because pine shavings have become increasingly difficult to obtain. Regionally, rice hulls, straw, and peanut hulls can be found in use by poultry producers for litter. Re-cycled paper products have received a lot of research and development, but have not had a great deal of acceptance by the poultry industry. Sand is another alternative bedding that is currently being tested in southern climates. Alternative litter materials for poultry will continue to be researched and evaluated, and pine shavings or sawdust will probably continue to be used as the benchmark comparison. However, while bird performance will always be a threshold criterion, cost and availability will ultimately determine the adoption of new or alternative litter materials by poultry growers and the poultry industry.

Body weight, livability, and feed conversion of a randombred control turkey line (RBC2) started in 1966 at The Ohio State University was compared with that of modern commercial turkeys hatched in 2003 when fed representative 1966- and 2003-type diets from hatch (March 5, 2003) through 196 d of age. Each pen of modern turkeys consisted of 5 birds each of the Nicholas, British United Turkeys of America, and Hybrid strains. Eight groups (i.e., 2 strains (RBC2 vs. modern), 2 sexes, and 2 dietary regimens) were randomly assigned into each of 4 blocks of 8 litter floor pens (32 total) for growout. Using the BW performance of the 2 strains on the modern feed as the basis, the study showed that the 2003 turkeys were approximately twice as heavy as the 1966 RBC2 at the 4 slaughter ages and that tom weights have increased by 186, 208, 227, and 241 g/yr, and hen weights have increased by 164, 179, 186, and 205 g/yr at 112, 140, 168, and 196 d of age, respectively, over the past 37 yr. Cumulative feed conversion (kg of feed/kg of BW) was approximately 20% better in the 2003 tom turkey on the 2003 feed (2.638) than in the RBC2 tom on the 1966 feed (3.278) at 20 wk of age. Feed efficiency to 11 kg of BW in the 2003 toms (2.132 at 98 d of age) was approximately 50% better than in the RBC2 toms (4.208 at 196 d of age). The number of days to reach that weight was halved during this period of time. Growth performance during the different periods of the study appeared to be strongly affected by type of feed used and seasonal changes in ambient temperature. Overall livability was very good for all groups, but the mortality level of the RBC2 was consistently higher, although not significantly so, than for the modern birds.

Stabilizing phosphorus (P) in poultry waste to reduce P losses from manured soils is important to protect surface waters, while pathogens in manures are an emerging issue. This study was conducted to evaluate CaO and Ca(OH)2 for killing manure bacterial populations (pathogens) and stabilizing P in poultry wastes and to investigate the influence on soils following amendment with the treated wastes. Layer manure and broiler litter varying in moisture content were treated with CaO and Ca(OH)2 at rates of 2.5, 5, 10, and 15% by weight. All treated wastes were analyzed for microbial plate counts, pH, and water-soluble phosphorus (WSP), while a few selected layer manures were analyzed by phosphorus X-ray absorption near edge structure (XANES). A loamy sand and a silt loam were amended with broiler litter and layer manure treated with CaO at rates of 0, 2.5, 5, 10, and 15% and soil WSP and pH were measured at times 1, 8, and 29 d. Liming reduced bacterial populations, with greater rates of lime leading to greater reductions; for example 10% CaO applied to 20% solids broiler litter reduced the plate counts from 793,000 to 6500 mL-1. Liming also reduced the WSP in the manures by over 90% in all cases where at least 10% CaO was added. Liming the manures also reduced WSP in soils immediately following application and raised soil pH. The liming process used successfully reduced plate counts and concerns about P losses in runoff following land application of these limed products due to decreased WSP.