Chick embryos feathers

Chick embryos exposed to rhodium on the eighth day of incubation were stunted mild reduction of limb size and feather growth inhibition were also observed. A number of rhodium compounds have tested positive in bacterial assays for genetic altering capability. The 2003 ACGIH threshold limit valuetime-weighted averages (TLV-TWAs) are 1.0 mg/m for the metal, l.Omg/m as Rh, insoluble compounds, and 0.01 mg/m as Rh, soluble compounds. 

Diazinon produces visible Type I and II ter-atisms when injected into chicken embryos. Type I teratisms (related to tissue NAD depression) included abnormal beaks, abnormal feathering, and shortened limbs. Type II teratisms, which included short and wryneck, leg musculature hypoplasia, and rump-lessness were associated with dismptions in the nicotinic cholinergic system. The severity of effects depended on embryo age and was dose related. Chick embryos (age 48 h) receiving 25.0 xg or more of diazinon/embryo had cervical notochord and neural tube malformations at 96 h, and short neck at 19 days. Wryneck occurred at doses ranging from... 

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-... 

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