gamma. -irradiated sewage solids in diets for sheep: nutritive evaluations and long-term assessments of possible toxicants

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5971189

Sanson, D W

Air-dried solids from primary (undigested) sewage sludge were collected at Las Cruces, New Mexico (a non-industrial town with population about 50,000). Bagged sewage solids were ..gamma..-irradiated (1 megarad dosage) to kill parasites and pathogenic organisms and evaluated as prospective feedstuffs for sheep. Pelleted, complete diets for gestating-lactating fine-wool ewes and for their growing-finishing lambs were formulated to be isonitrogenous with either 3.5% cottonseed meal (conventional diet) or 7% sewage solids (experimental diet). Digestibility of organic matter and crude protein, and biological value of nitrogen, did not differ (P > .05) between diets, as determined with wethers. Wether lambs fed to slaughter with conventional or experimental diets did not differ (P > .05) in rate of gain, carcass characteristics, element concentrations in blood and serum chemistry profiles, although liver Cu and kidney Pb levels were increased (P < .05) about 1.6-fold by sewage solids. Element contents of spleen and muscles did not differ (P > .05) due to diets. These studies confirm previous research at New Mexico State University which indicates that dried solids from municipal (primary) sludge provide nutritive benefits to sheep with risks of toxicity and heavy metal accumulation that appear tolerable where managed properly.

• OSTI ID: 5971189
• Country of Publication: United States
• Language: English

Related Subjects

560305* -- Chemicals Metabolism &amp; Toxicology-- Vertebrates-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL GROWTH
ANIMALS
BIOLOGICAL ACCUMULATION
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
COMPARATIVE EVALUATIONS
COPPER
DIET
DISTRIBUTION
DOMESTIC ANIMALS
ELEMENTS
FEEDING
GROWTH
INGESTION
INTAKE
LEAD
MAMMALS
MATERIALS
METALS
NUTRIENTS
RUMINANTS
SEWAGE
SEWAGE SLUDGE
SHEEP
SLUDGES
TISSUE DISTRIBUTION
TRANSITION ELEMENTS
VERTEBRATES
WASTES