Dietary concentration

BARDOCZ S, GRANT G, PUSZTAI A, FRANKLIN M F, CARVALHO A (1996) The effect of phytohaemagglutinin at different dietary concentrations on the growth, body composition and plasma insulin of the rat. Br J Nutr. 76 613-26. 

It has also been demonstrated in animals that lead blocks the intestinal responses to vitamin D and its metabolites (Smith et al. 1981). Dietary concentrations of lead in combination with a low phosphorus or a low calcium diet administered to rats suppressed plasma levels of the vitamin D metabolite, 1,25-dihydroxycholecaliferol, while dietary intakes rich in calcium and phosphorus protected against this effect (Smith et al. 1981). Thus, animals fed a diet high in calcium or phosphorus appear to be less susceptible to the effects of lead, because of hindered tissue accumulation of lead. 

In terrestrial vegetation, molybdenum and sulfur interfere with copper-induced deficiencies (Gupta 1979). Copper poisoning in cattle and other ruminants is governed by dietary concentrations of molybdenum and sulfate (Lewis et al. 1967 Todd 1969 Buckley and Tait 1981 Eisler 1989). Molybdenum and sulfur in mammalian diets cause a decrease in the availability of copper because of the formation of the biologically unavailable copper-thiomolybdate complex (Aaseth and Norseth 1986). Cattle die when grazing for extended periods on pastures where the ratio of copper to molybdenum... 

No data are available on copper toxicity to avian wildlife. Experiments with domestic poultry show that copper accumulates in livers of mallard ducklings at dietary concentrations as low as 15 mg/kg DW ration that gizzard histopathology and a reduction in weight gain of chicks (Gallus sp.) occur at 250 to 350 mg Cu/kg DW ration and that growth of turkey poults is improved at... 

Data are limited on zinc hazards to terrestrial invertebrates however, sensitive species are adversely affected at dietary concentrations >300 mg Zn/kg, or at soil concentrations >400 mg/kg (Table 9.9). 

On the basis of evidence presented herein, this author conservatively estimates that, in terms of total carbofuran in water, damage is possible to aquatic invertebrates at >2.5 pg/L and to teleosts at >15 pg/L. These levels could be attained during a heavy rainfall shortly after carbofuran treatment of adjacent fields. Among sensitive species of warm-blooded animals, dietary concentrations as low as 10 pg/kg ration have demonstrable effects, which were measurable only after extended periods postingestion. For comparison, this level is about 1/5 that allowed in meat by-products for... 

Results of chronic feeding studies show that dietary concentrations of chlordane between 0.76 and 5 mg/kg ration did not affect survival but did produce adverse effects on various species of laboratory animals and livestock (Table 13.5). Dietary concentrations of 0.76 mg/kg (equivalent to 0.09 mg/kg BW daily) were associated with enlarged livers in mice, 1.0 mg/kg produced elevated residues in cow s milk, 2.5 mg/kg resulted in liver pathology in rats, 3 mg/kg (equivalent to 0.075 mg/kg BW daily) produced high residues in fat of dogs, and 5 mg/kg caused liver pathology in mice (Table 13.5). 

Increased liver to BW ratios in both sexes. At higher dietary concentrations equivalent to 0.43 and 1.1 mg/kg BW daily, liver necrosis was observed in males (USEPA 1988)... 

Long-term feeding studies at dietary concentrations between 5 and 320 mg technical chlordane/kg... 

Birds seem comparatively resistant to diflubenzuron acute oral LD50 doses exceed 2000 mg/kg body weight (BW) dietary concentrations <4640 mg/kg FW are tolerated for at least 8 days and forest birds seem unharmed by recommended diflubenzuron application procedures to control pestiferous insects, except for a possible loss in fat reserves. Intraspecies differences in ability to metabolize diflubenzuron are probably large different strains of domestic chickens show significant differences in ability to accumulate and retain this compound. 

Brook trout, Salvelinus fontinalis Adults fed various dietary concentrations of... 

Organism Mirex Dietary Concentration (mg/kg ration) Exposure Interval Percent Mortality Reference ... 

Accumulations and adverse effects were noted at dietary concentrations of 10 to 13 mg 1080/kg feed. 

---