The Absorption and Retention of Carotene and Vitamin A by Hens on Normal and Low Fat Rations

The Comparative Utilization of Carotene and Pre-Formed Vitamin A in Broiler Type Chicks

“…Similar evidence has been reported by Harvey et al (1955), Ascarelli and Bondi (1957), and Laughland and Phillips (1955). Working with laying hens, Russell et al (1942) noted appreciably higher liver storage of carotene sources when the ration contained normal levels of fat as compared to the response on low fat diets. These investigators also concluded that vitamin A esters were more efficiently absorbed than carotene.…”

“…Series "B". As noted previously, there is published evidence (Russell et al, 1942) which indicates that better utilization of carotene is achieved in the presence of added fat. Test Series "B" was conducted for the purpose of checking this theory, using alfalfa meal (Sample #1) alone and in the presence of 4% stabilized tallow.…”

Supplementary Vitamin A and Choline in the Diet of the Growing Chick

“…Russell, Taylor and Polskin (1940) reported that the absorption of carotene was dependent upon the amount of fat in the diet. Following this work, Russell et al (1942) reported that only 50 to 60% of crystalline carotene or carotenes from plant tissues were absorbed by chickens when they were fed a diet containing 3.83% fat. The absorption of carotene was definitely decreased with a low fat (0.07%) diet whereas the vitamin A ester was satisfactorily absorbed on both low and normal fat diets.…”

Evidence for a Substance in Fish Solubles Which Enhances Vitamin A Storage in Chick Livers

“…Sellers and Eden (1949) reported that calves suffering from scours had only one-third as much vitamin A stored in the liver as did normal calves. Russell et al (1942) found that a normal amount of fat was necessary in the diet for maximum utilization of vitamin A.…”