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Biomedical subjects

J Bitman

Publications and source records attributed to J Bitman.

At least 91 records · Page 5Linked to original sources
PubMed1976

Increasing polyunsaturation of milk fats by feeding formaldehyde protected sunflower-soybean supplement.

A practical means of protecting fats of a feed concentrate containing high polyunsaturated fatty acids is described. A ground mixture of 30% soybeans and 70% sunflower seeds was treated with 1% formaldehyde to protect the unsaturated lipids from microbial hydrogenation in the rumen. This was fed as a supplement to two Holstein cows in amounts that were doubled weekly. These ranged from 524 to 8384 g/day and provided successively increasing intakes of 100, 200, 400, 800, and 1600 g of linoleic acid daily. Percent milk fat increased by more than one, and linoleic acid (C18:2) of milk fat increased from 2.5 to 20% with compensatory declines in myristic (C14:0) and palmitic (C16:0) acids. Cholesterol and vitamin E of plasma both doubled at the highest supplementation. Milk yield, solids-not-fat, protein and milk cholesterol were unaltered. Fat in feces doubled from about 3 to 6%. Daily linoleic acid content of feces increased from 25 g to 120 g, indicating a dietary loss of 7 to 10% of this polyunsaturated acid. These cheaper feed ingredients elevated the polyunsaturated fats in milk as effectively as the expensive purified casein and safflower oil supplements in previous experiments.

Animal Feed↗
PubMed1976

Antibody response and reduction in bursa of Fabricius and spleen weights of progeny of chickens fed PCBs.

In Experiment 1, polychlorinated biphenyls (Aroclors 1016, 1232, 1242, 1248, and 1254) were fed ad libitum to White Leghorn chickens at dietary levels of 5, 10, and 20 p.p.m. for 8 weeks. Hatchability of eggs from hens fed 10 and 20 p.p.m. of Aroclors 1232, 1242, and 1248 was reduced. The weights of the spleen and bursa of Fabricius of day-old chicks from hens fed 10 p.p.m. of Aroclors 1242 and 1248 or 20 p.p.m. of Aroclors 1232, 1242, 1248, and 1254 were less than those of control chicks. Body weights were similar to those of controls at hatching, but the 3 week weight gains of progeny from hens fed 20 p.p.m. Aroclors 1242 and 1248 were less than gains of control progeny. After replacement of the PCB diet with uncontaminated feed, hatchability improved within 2 weeks and by 8 weeks was similar to the hens were fed uncontaminated feed. In Experiment 2, hens were fed 10 p.p.m. 1248 ad libitum for 8 weeks. The progeny bursa weights were reduced, but the treatment did not interfere with interfere with antibody production. PCB treatment had no effect on antibody production after primary or secondary challenges with Brucella abortus. However, after the primary challenge, bursectomized birds of both the control and PCB groups produced significantly fewer antibodies than the nonbursectomized birds. Differential accumulations of the polychlorinated biphenyls occurred in the effs. Chlorinated biphenyls with relative retention times less than that of DDE accumulated to less than one-half of the dietary concentration whereas chlorinated biphenyls with retention times greater than that of DDE accumulated in the eff to a concentration equivalent to the dietary concentration.

Animals↗
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↗