vitamins for animal nutrition

Vitamins

Organic substances required by animals in small amounts for normal metabolism. Obtainable from the diet or a precursor in the diet and are NOT synthesized within body tissues a a rate good for metabolism

Vitamin recognition

A recognition developed that the known nutrients would not support life ( CHO, fats , proteins) Lunin in 1881

McCollum called

The fat soluble factor was found in butter fat-soluble A , as opposed to water-soluble B for the factor concerned in beri-beri

Fat Soluble

A,D,E,K

Water Soluble

VIT . C , B COMPLEX

1897 Eijkman

Isolated the cause of polyneuritis in poultry and beri-beri in man as being cured with rice hulls

1912 Funk

coined term ‘‘vitamin’’ after the amine fraction of rice hulls which he had isolated which prevented polyneuritis in bird

1913 Osborne and mendel

isolated a fat soluble substance from cod liver known as oil known as Vitamin A

Provitamins

compounds that give rise to vitamins

Antivitamins

Compounds that inhibits vitamins in some manner.

Vitamin A

Active as an alcohol, aldehyde,acetetae, palmitate and acid

Vitamin A palmitate

most popular synthetic form

vitamin A occurs

In animals only

Precursors called

Carotenoids exist in plants

Functions of vitamin A

Visual purple cycle rhodopsin which is the process of sight as a result of photochemical process

Deficiency in vitamin A

Reduced appetite, night blindness, xerophthalmia, runny eyes of cattle and sheep, increased respiratory problems, vaginal reproductive tract problems

Hypervitaminosis A

Skin thickening, suppressed keratinization

interference with bone development, loss of chondroitin sulfate

prolonged prothrombin time K -cures

cerebrospinal fluid pressure hydrocephalus

lowered plasma cholesterol in chicks

resorption of fetus

decreased appetite

carotene conversion

in rarts sheep goats and pigs carotene are not absorbed into the bloodstream but is converted into Vitamin A in the intestinal wall ( white fat species)

Carotene conversion in cow and horses

have considerable carotene in plasma , thus only part of carotene in feed is converted to Vitamin A (produces yellow fat)

vitamin A storage

Main storehouse is liver from 70-90% vitamin A found there. Remainder is in soft tissue such as fat depots, kidneys, and adrenals other organs.

Vitamin A sources

Fish oils, egg yolk, liver, milk fat,

Vitamin A sources

Carotenes, green color or chlorophyll mask yellow of carotenes. High in green leafy plants , decreases due to storage

Effects of chemical changes of vitamin A

Esterification, dehydrogenation, hydrogenation, heat in absence of moisture 6