Studies in vitamin A. 9. The role of the thyroid in carotene and vitamin A metabolism

Cama, H. R.; Goodwin, T. W.

doi:10.1042/bj0450236

Cited by 36 publications

(4 citation statements)

References 9 publications

(10 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…vitamin A. It has been shown recently by Cama & Goodwin (1949) that the estimation of serum vitamin A by the corrected ultra-violet absorption at 328 m/i is in close agreement with that obtained by the measurement of the transient blue colour with antimony trichloride at 617 m/t.…”

Section: Methodssupporting

confidence: 68%

The partition of carotenoids and vitamin A in the colostrum and milk of the cow and the goat

Chanda

1953

J. Agric. Sci.

View full text Add to dashboard Cite

The partition of carotenoids and vitamin A in the colostrum of nine cows and six goats and in the milk of three cows and two goats was determined using chromatographic and spectrophotometric methods. The following were the main results:1. The content of β-carotene and vitamin A in the colostrum decreased rapidly during the first nine milkings in both the cow and the goat. The rates of decline were logarithmic. Logarithmic regressions also showed that the decreases in β-carotene were more rapid than those of vitamin A.2. The heifers secreted more vitamin A in their colostral fat than did cows on the same ration. The vitamin A content of the colostral fat of goats was greater during the first lactation than in later lactations. There was no difference in the rates of decrease of the vitamin A content of heifer and cow colostrum, but the difference between the rates of decreases of colostral vitamin A of first and later lactation goats was significant.3. The colostral fat of cows at pasture contained more vitamin A than that of cows on winter rations. There was no difference between the logarithmic rates of decrease in the two groups during the first nine milkings. The colostral fat of four goats receiving winter rations was richer in vitamin A than that of three cows treated similarly, and this superiority of the goat over the cow persisted throughout lactation.4. There was no difference between the carotene content of the colostral fat of the first and later lactation cows. The yield of fat and β-carotene of the heifers was smaller than that of the cows. Cows at pasture secreted more β-carotene in their colostrum than the cows on winter rations. The presence of β-carotene was demonstrated in goat colostrum, although mature goat milk was free from any measurable quantity of carotenoids.

show abstract

Section: Methodssupporting

confidence: 68%

The partition of carotenoids and vitamin A in the colostrum and milk of the cow and the goat

Chanda

1953

J. Agric. Sci.

View full text Add to dashboard Cite

show abstract

“…I n these same experiments, thiouracil had equally pronounced, but opposite, effects-it decreased the amount of vitamin A in the milk and at the same time the carotene in the faeces increased. Similar effects have been reported from work with rats (Cama & Goodwin, 1949;Cama, Pillai, Sundaresan & Venkateshan, 1957) and from work with chickens (Chanda, 1956). There can be little doubt that in the experiments of Chanda et al (195 I b) and of Chanda & Owen (1952) the carotene of the food was appearing in the milk as vitamin A. Carotene dissolved in olive oil and subcutaneously injected does not give rise to carotene or vitamin A in the blood of goats (Chanda & Owen, unpublished observations).…”

Section: Thefate Of the Carotene Which Failed To Reappear In The Faecessupporting

confidence: 82%

Studies of the rate of passage and disappearance in the intestine of the goat of carotene dissolved in fat and mixed with chromium sesquioxide

1959

View full text Add to dashboard Cite

“…In the mesenteric lymph ducts the presence of the vitamin may be demonstrated by its fluorescence under ultraviolet irradiation soon after the oral administration of carotene. Cama & Goodwin (29) found that thyroxin and thiourea had no effect on the level of vitamin A in the plasma of rabbits. They could not confirm the alleged ability of iodinated casein or desiccated thyroid to convert carotene to vitamin A in vitro (30).…”

mentioning

confidence: 98%

Fat-Soluble Vitamins

Moore¹

1950

Annu. Rev. Biochem.

View full text Add to dashboard Cite

Studies in vitamin A. 9. The role of the thyroid in carotene and vitamin A metabolism

Cited by 36 publications

References 9 publications

The partition of carotenoids and vitamin A in the colostrum and milk of the cow and the goat

The partition of carotenoids and vitamin A in the colostrum and milk of the cow and the goat

Studies of the rate of passage and disappearance in the intestine of the goat of carotene dissolved in fat and mixed with chromium sesquioxide

Fat-Soluble Vitamins

Contact Info

Product

Resources

About