Dietetic complementary feeding stuff containing D-...
ß-Carotene
ß-carotene is a natural pigment found in plants, giving them their yellow or red colour.
Description:
ß-carotene is a natural pigment found in plants, giving them their yellow or red colour.
Function:
ß-carotene reacts with or scavenges “free radicals” directly and thus acts as an antioxidant. It enhances some aspects of immune function and acts as a precursor for vitamin A (retinol). Horses have the ability to convert ß-carotene to vitamin A in their small intestine. Moreover, it stimulates ovarian activity by its accumulation in the corpus luteum. It displays an enhanced oestrus, an increased pregnancy rate and reduces cycling disorders. “Foal heat” diarrhea of foals is said to be reduced by the elevated blood ß-carotene concentrations of their dams.
Sources:
Plants, including fruit and vegetables. Pasture legumes are particularly rich sources of ß-carotene. Mixed grass-clover pasture during growing season provides many times the daily requirement. Forage allowed to reach the seed stage or exposed to rains during the drying process or stored for a long period is likely to have lost a high proportion of ß-carotene.
Daily Requirements (NRC, 2007):
120 to 240 IU/kg body weight (72 to 144 μg/kg body weight).
Deficiency:
No ill effects may be apparent provided horses have a good store of vitamin A.
Excess:
No toxicity has been reported.
When problems may occur?
When deficiency in ß-carotene leads to vitamin A deprivation. Clinical signs of vitamin A deficiency occur under fairly extreme conditions of deprivation. Deficiencies may arise from failure to supplement feed or from the provision of badly stored old feed: - Horses stabled for most of their time, consuming little or no fresh herbage
- Horses fed with old forage stored for a long time, with no other intake
- Breeding mares deprived of pasture during winter