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Biomedical subjects

G F Fries

Publications and source records attributed to G F Fries.

At least 37 records · Page 2Linked to original sources
PubMed1977

Retention and excretion of polychlorinated biphenyl residues by laying hens.

Commercial polychlorinated biphenyl (PCB) mixtures with 21, 32, 42, 48, 54, and 68% chlorine were fed to caged White Leghorn hens at 20 p.p.m. for nine weeks. The 42, 48, and 54% mixtures were also fed at 2 p.p.m. Residues in egg at nine weeks were 0.7, 2.4, 14.4, 9.3, 11.4, and at 21.5 p.p.m. for the 21, 32, 42, 48, 54, and 68% chlorine PCBs, respectively. Corresponding values in body fat were 24.0, 51.1, 89.3, 90.5, 124.5, and 52.4 p.p.m., respectively. Levels in eggs and body fat of groups fed 2 p.p.m. were approximately one-tenth the levels in the 20 p.p.m. group. After seven weeks of control feed, the values for the 20 p.p.m. groups were 0.7, 1.8, 2.8, 3.0, 7.2, and 1.8 for eggs and 8.1, 22.4, 26.4, 39.8, 91.7, and 43.6 for body fat. Estimated recovery of consumed PCBs increased from 8% to 55% as chlorine increased from 21 to 68%. Residues in excreta was about 10% of intake for all PCBs. Body fat retention was greater than egg elimination for 21 through 48% chlorine PCB, about the same for 54% and much less for the 68% chlorine PCB. The ratio of egg: fat residue in contaminated birds was .084:1.

Adipose Tissue↗
PubMed1976

Hexachlorobenzene retention and excretion by dairy cows.

Two groups of three cows each were fed either 5 or 25 mg of hexachlorobenzene per day for 60 days. A reference compound, DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), was fed to the cows at the same rate. Residues were determined in milk at 5-day intervals during the 60-day dosing period and for 60 days after dosing was stopped. The concentration of hexachlorobenzene in milk fat increased more slowly than did that of the reference compound during feeding. The ratio of the two was 1:2 at 10 days, but approached 1:1 after 40 days of feeding. The average concentrations in milk fat for the 40th to 60th days of feeding were 9.0 and 10.4 ppm with the 25-mg/day intake and 2.1 ppm for each compound with the 5-mg/day intake. Corresponding values in subcutaneous body fat were 8.8, 8.0, 1.9, and 1.4 ppm at 60 days. Milk fat concentrations of hexachlorobenzene declined 32% and those of the reference 51% within 15 days after feeding stopped. Thereafter, the decline was slower but similar for both compounds. Biological half-lives ranged from 29 to 64 days for individual cows. The milk fat:body fat concentration ratio was .87:1 for hexachlorobenzene and .71:1 for the reference during the 60 days when cows were not fed the compounds.

Adipose Tissue↗
PubMed1975

Excretion of polybrominated biphenyls into the milk of cows.

Four cows each were fed 10 mg/day polybrominated biphenyl for 60 days. Concentration in milk fat reached a steady state at 3.07 ppm within 30 days. When feeding polybrominated biphenyl was stopped, the concentration declined 71% in the first 15 days. The decline was slower thereafter, with a half-life of 58 days. Effects on health and production of the cows were not adverse for as long as 1 yr after the compound was fed.

Animal Nutritional Physiological Phenomena↗
PubMed1975

Toxicity of certain polychlorinated and polybrominated biphenyls on reproductive efficiency of caged chickens.

The biphenyls tested with caged White Leghorn pullets were polychlorinated biphenyl (PCBs) Aroclors 1232, 1242, 1248, 1254 and 1016 and polybrominated biphenyl (PBB) PBP-6 at the 5, 10 and 20 p.p.m. levels. These pollutants exerted no adverse effects on egg production, egg weight, egg shell thickness, feed consumption, adult body weight changes, livability and fertility after 8 weeks of biphenyl feeding, irrespective of biphenyl level or compound. Hatchability of fertile eggs as a result of biphenyl feeding was significantly affected by 10 or 20 p.p.m. and by three PCB compounds (Aroclors 1232, 1242, 1248). The hatchability (%) of eggs laid by pullets fed 10 and 20 p.p.m. declined to 78 and 45, respectively, for Aroclor 1232, 48 and 5 for Aroclor 1242 and 40 and 5 for Aroclor 1248 after 6 weeks of biphenyl feeding, as compared with 90 for the control group. The most common embryonic abnormality was edema in the neck and rump areas. Biphenyl supplementation in the maternal diet also caused a shift in the peak pattern of embryonic death. Progeny growth as a result of biphenyl in the maternal diet was significantly depressed by 10 or 20 p.p.m. and by Aroclors 1242 and 1248. The level of the three PCBs found to be toxic to chickens appears to lie somewhere between 5 and 10 p.p.m.

Animals↗
PubMed1971

Nonconversion of o,p'-DDT to p,p'-DDT in rats, sheep, chickens, and quail.

The finding of appreciable quantities of p,p'-DDT after feeding o,p'-DDT to rats led to the proposal of a theory, that an isomeric metabolic conversion occurs. The presence of p,p'-DDT as an impurity in supposedly pure samples of o,p'-DDT is the correct explanation for the appearance of p,p'-DDT. Purified o,p'-DDT and (14)C-labeled o,p'-DDT yielded no data to support the idea that o,p'-DDT is converted to the p,p'-DDT isomer.

Adipose Tissue↗