Factor, chick edema

Variations in the manufacturing process of 2,4,5-trichloro- and pentachlorophenol (but not 2,4-dichlorophenol) have sometimes resulted in contamination of the product by small amounts of heterocyclic impurities (4,5). Of these, the chlorinated dibenzo-p-dioxins such as TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) have received much scientific and public attention because of their real or potential toxicity 6, 7), [Chick edema factor, a curious toxicological problem to poultry producers for several years, has been shown to be composed of chlorodibenzo-p-dioxins (8).]... 

A consistent pericardial edema in chickens gave rise to the term chick edema disease (chick edema factor) (I). Two known outbreaks of the disease in the broiler industry resulted in a great loss of chickens. A lipid residue from the manufacturing fatty acids, being used as a feed ingredient, was a principal source of the toxic substance. Contamination of the lipid component with polychlorodibenzo-p-dioxins was attributed as the causal agent. 

In addition to its extremely high oral toxicity, skin contact with substances containing 2,3,7,8-tetrachlorodibenzo-p-dioxin may allow toxicity in the form of chloracne, a condition characterized by eruptions of the skin on the face, neck, and back. Also, chlorinated dibenzo-p-dioxins have been associated with the chick edema factor, a disease of chicks associated with contaminated fats or oils used in the manufacture of their feed. 

Chick edema disease became a serious economic problem by the mid-1950s, by which time millions of broilers had succumbed to it in the U.S. The problem was traced to toxic components in the unsaponifiable fraction of certain low cost feed fats Introduced into the chick diet to increase the caloric intake (ref. 121c). Symptoms included fluid in the heart sack and abdominal cavity, subcutaneous edema and liver necrosis. Injection of purified chick edema factor into fertile eggs resulted in lower hatch yield, embryonic deformities and edema. Unhatched embryos exhibited a variety of defects (malformed beaks, leg deformities, no development of the right mesencephalon, and eye defects). Hatched embryos were growth-retarded, with sparse and defective feathers. The isolated toxin was ultimately identified as 1.2,3,7.8,9-... 

Campbell AD, Firestone D, Westly B. 1971. Chick edema factor—toxic dioxins. In WestleyB, ed. International Symposium on identification and measurement of environmental pollutants, Ottawa, Ontario, Canada, June 14-17, 1971. Ottawa, Canada The Symposium, 105-108. 

All fat products must be below tolerances for toxic chemicals and pesticide residues certification is available from most renderers fats used in poultry rations must be free of the chick edema factor and all fats should be devoid of contaminants such as heavy metals. 

Consistent performance in today s feed conversion-animal production industries requires consistent feedstuffs. In addition to providing products free of chick edema factors, pesticides, herbicides, polychlorinated biphenyls (PCBs), and other hazardous contaminants, the tallow and grease supplier is expected to deliver products with increasingly consistent fatty acid profiles. This requires appropriate... 

Grade Variety of technical grades, grade free from chick edema factor, USP, FCC, 99+%. A purified technical oleic acid containing 90% or more oleic, 4% maximum linoleic, and 6% maximum saturated acids is available. 

Grade USP, technical, available free from chick edema factor. 

The toxicity of the dioxins was first observed in 1895 in workers in the chemical industry in Germany. They developed a skin complaint called chloracne, believing it was caused by chlorine. In 1957, millions of chickens in the eastern and midwestem U.S. died of a disease characterized by excessive fluid in the pericardial sac. The name chick edema factor was therefore applied to the component(s) in the feed responsible for this symptom. Liver and kidney damage was also observed. Similar outbreaks of the disease occurred in 1960 and 1969. A contaminant in trichlorophenol, or products produced from trichlorophenol, caused the chick edema disease and chloracne. Twelve years later its structure was published (Cantrell et al., 1969). The Dow Chemical Company had been aware of a highly toxic impurity formed in small amounts from the production of 2,4,5-T as early as 1950. 

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