Avian and Poultry Biology Reviews

Avian and Poultry Biology Reviews 14 (4), 2003

Current Pollution and Odor Control Technologies for Poultry Production

K. H. Nahm

Feed and Nutrition Laboratory, College of Natural Resources, Taegu University, Gyong San, 712 ± 714, South Korea

ABSTRACT

Concentrated poultry production has resulted in pollution of water by nitrogen (N) and phosphorus (P), and air due to ammonia (NH3), odors and dust within the poultry barns. Chemical additives containing calcium (Ca), aluminum (Al), or iron (Fe) reduce NH3 emissions 35 to 99% and soluble P31to 95%, depending on the chemical and concentration used. Poultry feedmanipulation methods for reducing Nand P contents in poultry manure involve reducing protein contents and supplementing with synthetic amino acid to reduce N excretion up to 29.14%. Reducing soluble P contents in broiler diets (40% of NRC requirements) during the withdrawal period reduced soluble P contents in the manure. Enzyme supplements in poultry feed improve dry matter digestibility and phytic P utilization from grain diets, thereby reducing P content in manure. Litter materials increase carbon content of manure and sawdust has specifically been found to reduce the nitrogen in manure by 21%. Covers reduce odor production (impermeable covers by 70^85% and permeable covers by 45^85%) from manure storage areas. Filter systems reduce dust production and accompanying odors by 80% from poultry barns. Certain land application techniques of manure reduce odor and ammonia by 90%. Ozone lowers NH3 levels in poultry buildings up to 25% and also eliminates pathogens. Mixing fly ash with manure reduces soluble P contents in stockpiled manure up to 85% and composted manure up to 93%. Addition of vitaminDalone to poultry feed improves phytate P retention from31to 68%,while usewith phytase improved retention to 79%. Using combinations of themethodswouldmaximize their effectiveness.

Keywords: pollution, N, P, NH3, dust, chemical, enzyme, litter, ozone, ¯y ash, vitamin D

Wet Foods for Poultry

J. Michael Forbes

Centre for Animal Sciences, School of Biology, University of Leeds, Leeds LS2 9JT, UK

ABSTRACT

Historically feeding of wetmashes to poultry has not been recommended for use in large-scale commercial poultry production, on the basis that it does not offer any nutritional advantage andis difficult to apply.However, food soaked and re-driedisutilised more efficiently and recent work has shown repeatedly thatmixing conventional foodswith sufficient water tomake a porridgy consistency (typically1.5 ^ 2.0 kg of water per kg of air-dry food) either increases the proportional retention of nutrients bybroilers or increases voluntary food intake. Foods of lower nutrient density (e.g.with a high content of cereal) can therefore be used to get the desired growth rate.The improvement in digestionwithwet feeding is not likely to be due to activation of endogenous enzymes in the feed but probably involves more rapid penetration of digestive juices into food particles, more rapid and complete digestion and thus the opportunity for higher food intakes.The benefits are seen with both male and female broilers andare greater the earlier inlife thewet feedingis started.Growing ducks andlayinghens are alsomore efficientwithwet feeding. Practical advantages of giving foodin the wet forminclude the ability to use high levels of cerealswithout pelleting, the opportunity to fine-tune the composition of the diet on a daily basis (e.g. amino acids, medicines) and the great reduction in dust in intensive houses. Disadvantages include the danger of wet litter and dirty feathers, risk of spread of disease and the high cost of feeding equipment. So far wet feeding is not in commercial use although itmight be of particular benefit in hot environments.

Keywords: broiler chickens; wet feeding; digestive ef®ciency

Abstracts:

INCUBATION AND FERTILITY RESEARCH GROUP
{WPSA Working Group 6 (Reproduction)}
2003 Meeting ±University of Lincoln, UK
4th - 5th September 2003