Vitamin A deficiency in drought-fed sheep

1972 ◽  
Vol 12 (54) ◽  
pp. 19 ◽  
Author(s):  
RF Bayfield ◽  
DG Saville ◽  
RH Falk
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Liver Vitamin

Vitamin A deficiency was observed in sheep that had been maintained for 55 weeks on grain-based diets. Mean (� S.E.) plasma and liver vitamin A levels were 6.1 � 5.7 �g/100 ml and 23.9 � 33.0 �g/g respectively. When the sheep were treated with vitamin A or transferred to green pasture, deficiency signs disappeared rapidly and after five weeks, mean vitamin A had increased to 23.3 � 5.7 �/100 ml in plasma, and after nine weeks to 179.5 � 42.5 �g/g in liver.

Vitamin A Status and Hepatic Drug Metabolism in the Rat

1973 ◽  
Vol 51 (1) ◽  
pp. 6-11 ◽  
Author(s):  
G. C. Becking
Keyword(s):  
Vitamin A ◽  
Drug Metabolism ◽  
Vitamin A Deficiency ◽  
Hepatic Drug Metabolism ◽  
Deficient Diet ◽  
Hepatic Drug ◽  
Vitamin A Status ◽  
Cytochrome P 450 ◽  
Liver Vitamin

The effect of vitamin A status on hepatic drug metabolism was studied in rats. Animals were fed diets with and without vitamin A for 20 and 25 days. Weight gains of control and deficient animals were not significantly different, whereas liver vitamin A levels had decreased to less than 10% of control animals after 20 days and were essentially zero after eating the deficient diet for 25 days. Aniline metabolism in vitro and aminopyrine metabolism in vitro and in vivo were significantly lower in male weanling rats fed a vitamin A deficient diet for 20 days. No alteration in in vitro p-nitrobenzoic acid metabolism was noted after 25 days on the test. Vitamin A deficiency did not alter microsomal protein levels or cytochrome c reductase activity but deficient animals did have a lower microsomal cytochrome P-450 content. Hepatic enzyme activities and cytochrome P-450 levels were restored to values approaching those found in control animals by feeding vitamin A deficient rats the vitamin A containing diet for 21 days. Liver vitamin A levels were markedly increased after re-feeding studies but were still significantly lower than control animals.

Biological evidence to define a vitamin A deficiency cutoff using total liver vitamin A reserves

2021 ◽  
pp. 153537022199273
Author(s):  
Sherry A Tanumihardjo
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Biological Response ◽  
Population Based ◽  
Total Liver ◽  
Long Term Storage ◽  
Micronutrient Status ◽  
Term Storage ◽  
Liver Vitamin

Vitamin A is a fat-soluble vitamin involved in essential functions including growth, immunity, reproduction, and vision. The vitamin A Dietary Reference Intakes (DRIs) for North Americans suggested that a minimally acceptable total liver vitamin A reserve (TLR) is 0.07 µmol/g, which is not explicitly expressed as a vitamin A deficiency cutoff. The Biomarkers of Nutrition for Development panel set the TLR cutoff for vitamin A deficiency at 0.1 µmol/g based on changes in biological response of several physiological parameters at or above this cutoff. The criteria used to formulate the DRIs include clinical ophthalmic signs of vitamin A deficiency, circulating plasma retinol concentrations, excretion of vitamin A metabolites in the bile, and long-term storage of vitamin A as protection against vitamin A deficiency during times of low dietary intake. This review examines the biological responses that occur as TLRs are depleted. In consideration of all of the DRI criteria, the review concludes that induced biliary excretion and long-term vitamin A storage do not occur until TLRs are >0.10 µmol/g. If long-term storage is to continue to be part of the DRI criteria, vitamin A deficiency should be set at a minimum cutoff of 0.10 µmol/g and should be set higher during times of enhanced requirements where TLRs can be rapidly depleted, such as during lactation or in areas with high infection burden. In population-based surveys, cutoffs are important when using biomarkers of micronutrient status to define the prevalence of deficiency and sufficiency to inform public health interventions. Considering the increasing use of quantitative biomarkers of vitamin A status that indirectly assess TLRs, i.e. the modified-relative-dose response and retinol-isotope dilution tests, setting a TLR as a vitamin A deficiency cutoff is important for users of these techniques to estimate vitamin A deficiency prevalence. Future researchers and policymakers may suggest that DRIs should be set with regard to optimal health and not merely to prevent a micronutrient deficiency.

scholarly journals VITAMIN A AND CAROTENE STUDIES WITH FATTENING BEEF CATTLE

1963 ◽  
Vol 43 (1) ◽  
pp. 31-38 ◽  
Author(s):  
W. K. Roberts ◽  
G. D. Phillips
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Daily Intake ◽  
Conversion Ratio ◽  
Feeding Period ◽  
Feed Conversion ◽  
Supplemental Vitamin ◽  
Feeding Trials ◽  
Effect Of Feeding ◽  
Liver Vitamin

Three feeding trials were conducted to study the effect of feeding various levels of vitamin A or carotene on weight gains, feed conversion and changes in liver vitamin A stores of fattening steers. The daily intake of 6,000 I.U. of vitamin A did not prevent vitamin A deficiency during a 126-day feeding period, when average initial liver vitamin A stores of the steers were 6.8 micrograms per gram of fresh liver. On the other hand, steers with liver vitamin A stores of 51.8 micrograms per gram of fresh liver, and receiving no supplemental vitamin A or carotene, showed no vitamin A deficiency symptoms and gained approximately the same as steers receiving 17,958 or 35,875 I.U. of vitamin A daily during a 133-day feeding period. Steers receiving the vitamin A-carotene free rations did not require significantly more feed per 100 pounds gain than steers receiving similar rations and supplemented with various levels of vitamin A or carotene. Initial liver vitamin A stores of 73.4 micrograms per gram of fresh liver were not maintained in fattening steers receiving 72,100 I.U. of vitamin A daily during 112 days. Steers consuming 63.3 milligrams of B-carotene or 25,000 I.U. of vitamin A daily showed similar losses in initial liver vitamin A stores during 133 days, suggesting a conversion ratio of carotene to vitamin A of approximately 8.4:1, on a weight basis.

Quantification of Vitamin A in Fortified Rapeseed, Groundnut and Soya Oils Using a Simple Portable Device: Comparison to High Performance Liquid Chromatography

2013 ◽  
Vol 83 (2) ◽  
pp. 122-128 ◽  
Author(s):  
Cécile Renaud ◽  
Jacques Berger ◽  
Arnaud Laillou ◽  
Sylvie Avallone
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Vitamin A ◽  
High Performance ◽  
Vitamin A Deficiency ◽  
Developed Countries ◽  
Portable Device ◽  
Least Developed Countries ◽  
Control Food ◽  
Assay Precision

Vitamin A deficiency is still one of the major public health problems in least developed countries. Fortification of vegetable oils is a strategy implemented worldwide to prevent this deficiency. For a fortification program to be effective, regular monitoring is necessary to control food quality in the producing units. The reference methods for vitamin A quantification are expensive and time-consuming. A rapid method should be useful for regular assessment of vitamin A in the oil industry. A portable device was compared to high-performance liquid chromatography (HPLC) for three plant oils (rapeseed, groundnut, and soya). The device presented a good linearity from 3 to 30 mg retinol equivalents per kg (mg RE.kg- 1). Its limits of detection and quantification were 3 mg RE.kg- 1 for groundnut and rapeseed oils and 4 mg RE.kg- 1 for soya oil. The intra-assay precision ranged from 1.48 % to 3.98 %, considered satisfactory. Accuracy estimated by the root mean squares error ranged from 3.99 to 5.49 and revealed a lower precision than HPLC (0.4 to 2.25). Although it offers less precision than HPLC, the device estimates quickly the vitamin A content of the tested oils from 3 or 4 to 15 mg RE.kg- 1.

Research Recommendations for Applying Vitamin A-Labelled Isotope Dilution Techniques to Improve Human Vitamin A Nutrition

2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 52-59 ◽  
Author(s):  
Sherry A. Tanumihardjo ◽  
Anura V. Kurpad ◽  
Janet R. Hunt
Keyword(s):  
Public Health ◽  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Human Subjects ◽  
The Body ◽  
Pool Size ◽  
Serum Retinol ◽  
Vitamin A Status ◽  
Status Assessment ◽  
Total Body

The current use of serum retinol concentrations as a measurement of subclinical vitamin A deficiency is unsatisfactory for many reasons. The best technique available for vitamin A status assessment in humans is the measurement of total body pool size. Pool size is measured by the administration of retinol labelled with stable isotopes of carbon or hydrogen that are safe for human subjects, with subsequent measurement of the dilution of the labelled retinol within the body pool. However, the isotope techniques are time-consuming, technically challenging, and relatively expensive. There is also a need to assess different types of tracers and doses, and to establish clear guidelines for the use and interpretation of this method in different populations. Field-friendly improvements are desirable to encourage the application of this technique in developing countries where the need is greatest for monitoring the risk of vitamin A deficiency, the effectiveness of public health interventions, and the potential of hypervitaminosis due to combined supplement and fortification programs. These techniques should be applied to validate other less technical methods of assessing vitamin A deficiency. Another area of public health relevance for this technique is to understand the bioconversion of β-carotene to vitamin A, and its relation to existing vitamin A status, for future dietary diversification programs.

Vitamin A deficiency is associated with disease severity in patients with liver cirrhosis

2020 ◽  
Author(s):  
M Nagel ◽  
C Labenz ◽  
M Nguyen-Tat ◽  
N Cabezas Wallscheid ◽  
C Czauderna ◽  
...  
Keyword(s):  
Liver Cirrhosis ◽  
Vitamin A ◽  
Disease Severity ◽  
Vitamin A Deficiency

Mitral Valve Replacement in an Adult with Left Pulmonary Agenesis

2015 ◽  
Vol 18 (3) ◽  
pp. 109
Author(s):  
Huseyin Saskin ◽  
Mustafa Idiz ◽  
Cagri Duzyol ◽  
Huseyin Macika ◽  
Rezan Aksoy
Keyword(s):  
Mitral Valve ◽  
Vitamin A ◽  
Valve Replacement ◽  
Viral Infections ◽  
Vitamin A Deficiency ◽  
Pulmonary Agenesis ◽  
Pulmonary Vessels ◽  
Live Births ◽  
Factors Associated ◽  
Female Predominance

Pulmonary agenesis is associated with the absence of pulmonary vessels, bronchi, or parenchyma. This condition usually occurs between the 4th and 5th week of gestation during the embryonic phase. Etiopathogenic factors associated with pulmonary agenesis are not fully understood. In the literature, genetic and teratogenic factors, viral infections, and vitamin-A deficiency are shown to be associated with pulmonary agenesis [Malcon 2012]. This condition may be seen unilaterally or bilaterally. Although the precise rate of incidence is unknown, it is estimated to occur in one of every 10,000 to 12,000 live births [Yetim 2011]. There is a 1.3:1 female predominance with unilateral agenesis [Halilbasic 2013]

Retinol, α-Tocopherol and Vitamin D3 in White MuscleDisease

2018 ◽  
Vol 74 (1) ◽  
pp. 6029-2018
Author(s):  
HANDAN MERT ◽  
SERKAN YİLDİRİM ◽  
IBRAHİM HAKKİ YORUK ◽  
KİVANC IRAK ◽  
BAHAT COMBA ◽  
...  
Keyword(s):  
Vitamin A ◽  
Vitamin D3 ◽  
White Muscle ◽  
Bone Structure ◽  
Early Stage ◽  
Vitamin A Deficiency ◽  
Muscle Disease ◽  
Control Group ◽  
White Muscle Disease ◽  
Fat Soluble Vitamins

Vitamins are essential for the health of all living organisms. Vitamins E, A, D and K are known as fat-soluble vitamins, and deprivation of vitamin E causes various disorders, especially in the reproduction and cardiovascular systems and in muscle functions. Vitamin A, on the other hand, has roles in various biological functions – like eyesight – and the growth, reproduction and differentiation of epithelial cells. Vitamin A deficiency leads to the keratinization of the epithelium, and disorders related to the metaplasies of the genital and genitourinary systems. Conversely, vitamin D is defined as a pro-hormone and is responsible for Cahomeostasis, and thus indirectly affects the bone metabolism, bone structure, and cellular and neural functions of Ca. White muscle disease (WMD) can occur in newborn lambs, but is more commonly seen in lambs of up to 3 months of age. In this study, 30 lambs of 3 to 50-days-old from different flocks diagnosed with White Muscle Disease (WMD) were selected as research material, while the control group consisted of 8 healthy lambs. With the aim of clarifying the cause of WMD, serum fat-soluble vitamins, retinol, α-tocopherol and vitamin D3 levels were determined in 16 lambs. Gluteal and heart musclet issue samples also were taken from 30 lambs with WMD. The vitamin levels of the samples were analysed by HPLC. The levels of serum α-tocopherol, retinols, and vitamin D3 were foundto be low in the diseased animals, but only retinol (p<0.001) and α-tocopherol (p<0.0011) level differences were statistically relevant. Macroscopically, Zenker’s necrosis was determined in the heart muscles of 17 lambs, and in the gluteal and chest muscles of 6 lambs. 7 lambs displayed necrosis in both their heart and in gluteal muscles. The samples were analyzed microscopically to reach similar findings: swollen homogeneous pink muscles, pycnotic nuclei, and hyperaemic and haemorrhagic blood vessels in gluteal, chest and heart muscles. Hyaline degeneration and Zenker's necrosis, dystrophic regions in necrotic areas, cc was detected as a severe disease in lambs at an early stage of life with advanced degeneration in different muscle tissues. Deficiency of fat-soluble vitamins was also detected in the sick animals. Control group lambs had higher levels of α tocopherol and retinol (p<0.001) compared to the sick lambs. .

Prevalence of iron deficiency and its association with vitamin A deficiency in preschool children

2005 ◽  
Vol 81 (2) ◽  
pp. 169-174 ◽  
Author(s):  
Ivan S. Ferraz ◽  
Júlio C. Daneluzzi ◽  
Hélio Vannucchi ◽  
Alceu A. Jordão Jr. ◽  
Rubens G. Ricco ◽  
...  
Keyword(s):  
Preschool Children ◽  
Iron Deficiency ◽  
Vitamin A ◽  
Vitamin A Deficiency

Prevalence of clinical and sub-clinical vitamin a deficiency among rural preschool children of West Bengal, India

2010 ◽  
Vol 48 (1) ◽  
pp. 47-49 ◽  
Author(s):  
N. Arlappa ◽  
N. Balakrishna ◽  
A. Laxmaiah ◽  
K. Madhavan Nair ◽  
G. N. V. Brahmam
Keyword(s):  
Preschool Children ◽  
Vitamin A ◽  
West Bengal ◽  
Vitamin A Deficiency
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