Adult mallards (Anas platyrhynchos) were fed South Louisiana crude oil as 0.25 and 2.5% of the total diet for 26 weeks to assess the chronic effects of oil ingestion. Additional birds were fed diets containing either 1.0% of a paraffin mixture or clean feed. No birds died during the study, nor were their body weights significantly depressed. Oviduct weight at necropsy was greatly reduced in hens on the 2.5% oil diet and also was significantly reduced in hens on the 0.25% oil diet when compared with controls. Male reproductive organs were not atrophied by treatment. Hens on oil-treated diets laid fewer eggs than those on the control diet; however, eggs from treated hens hatched as well as those from controls when artificially incubated. Pathological or biochemical alterations were no greater in the treated birds than in controls.
Additional publication details
Response of adult mallard ducks to ingested South Louisiana crude oil