The Relationship of the Vitamin D Intake of the Hen to the Antirachitic Potency of the Eggs Produced

Naturally enhanced eggs as a source of vitamin D: A review

“…A lot of studies were published in the 1920'ties and 1930'ties regarding how to increase the vitamin D content in eggs. It was shown that the content of vitamin D in egg yolk could be increased by adding vitamin D to the feed of laying hens (Bethke, Kennard, & Sassaman, 1927;Branion, Drake, & Tisdall, 1935;DeVaney, Munsell, & Titus, 1933;Guerrant, Kohler, Hunter, & Murphy, 1935) or by irradiating nonsupplemented hens from above (Farrell, 1924;Hart et al, 1925;Hendricks, 1931;Hughes & Payne, 1924;Hughes, Payne, Titus, & Moore, 1925;Maughan & Maughan, 1933). However, when Carson & Beall (1955) supplemented hens with approximately 29 μg vitamin D/kg feed and exposed them to UVB from above, no increase of vitamin D in the eggs were observed.…”

Cholecalciferol and 25-Hydroxycholecalciferol Content of Chicken Egg Yolk As Affected by the Cholecalciferol Content of Feed

“…In previous studies the antirachitic potency of egg yolk was shown to be dependent on the antirachitic intake of the hen producing it (Bethke et al, 1927;Guerrant et al, 1935). Guerrant et al (1935), however, reported that the ability of the hen to transfer the antirachitic factor or factors from its diet to the egg is limited. More recently, Mattila et al (1992) found remarkable variation in the cholecalciferol content of eggs produced by hens receiving different types of feed.…”

The Influence of Fat-Soluble Vitamins on Egg Production and Egg Shell Composition

“…Bethke, Kennard, and Sassaman (1927) have reported that 2 percent of cod liver oil added to the basal diet materially enhanced the vitamin D content of the eggs. Guerrant, Kohler, Hunter, and Murphy (1935) concluded from their studies of the ration of laying hens that there is a relationship between the amounts of cod liver oil fed and the antirachitic potency of the eggs produced.…”