Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dynamics of vitamin A turnover in the blood and semen of astrakhan ram-sires was being studied for determining the ways of its transport to mature sperms. By means of high pressure liquid chromatography it was found that concentrations of retinol in the blood and retinyl palmitate in the semen of rams, suffering from hypovitaminosis A, rose simultaneously during the first 24 hours after feeding the animals with labelled retinol. According to the data on the specific activity of labelled vitamin A in the blood and semen a significant portion of the vitamin was transfered into the semen from the blood together with the secretions of epididymis and/or another sexual glands. The role of vitamin A in epididymal sperm maturation is discussed. A more prolonged increase of vitamin A levels in the blood and semen of the animals under study was achieved after double feeding of each animal with 60 mg of vitamin A.
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PMID:[Dynamics of vitamin A metabolism in the blood and semen of karakul ram sires]. 647 11

Sixteen Hereford bulls (16 mo of age, 462 kg average body weight) were used in each of 2 yr to evaluate the effects of hypovitaminosis A on seminal quality and sperm production. Bulls were fed a high-concentrate diet with (+VIT) or without (-VIT) supplemental Vitamin A until the apparent onset of hypovitaminosis A (28 and 32 wk in Year 1 and 2, respectively). Half of the bulls on each treatment were then slaughtered and those remaining were re-alimented with Vitamin A. Plasma retinol concentration in -VIT bulls reached a nadir at approximately 25 wk. In Year 1, the proportion of progressively motile spermatozoa was lower in -VIT bulls after 17 wk but returned to that of the +VIT group after re-alimentation. The proportion of spermatozoa with primary morphological defects appeared to be greater in -VIT bulls compared to +VIT bulls by 26 and 24 wk in Year 1 and 2, respectively. The incidence of these defects declined in -VIT bulls upon re-alimentation, and approached the incidence observed in +VIT bulls by 8 to 12 wk of re-alimentation. Hypovitaminosis A decreased paired testes weight, daily sperm production, and epididymal sperm reserves but did not affect daily gain. Prolonged dietary Vitamin A deficiency impaired semen quality and sperm production in the absence of other clinical symptoms. However, under practical feeding conditions, diets that result in long-term, marginal Vitamin A deficiency or a relatively short-term absence of Vitamin A intake probably would have minimal effects on spermatogenesis.
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PMID:Seminal quality and sperm production in beef bulls with chronic dietary vitamin A deficiency and subsequent re-alimentation. 1672 12