Why hasn't it harmed my horses before ? :
UF advised in a seminar April 29, 2015 that this weed was not an issue 15yrs ago therefore, it has only RECENTLY been included in veterinary curriculum. (2014) That is why many vets in the field TODAY, and especially in the past, do not recognize this culprit and have been and may have unintentionally MIS-DIAGNOSED Creeping Indigo as many other illnesses such as EPM, EEE, Rhino Virus and many other similarly behaving illnesses simply because, they were not aware. The toxin in Creeping Indigo- Indospicine, does not show up on the current US blood panels.
UF has discussed that they also believe the unusually warm winters we have had in FL the last few years (2012-2014) may be a huge contributing factor to the spike of outbreaks we are experiencing currently. It seems the weed has reached full saturation of the state, with the exception of properties that have been treated with effective herbicides consistently.
Also, you must consider that as horses eat this weed- they are re-seeding it. So, as the years/months go on- the quantity and availability of CI increases. Because, a horses digestive track is less efficient than cows and can help SPREAD the seeds.
A cow's digestive system (ruminant) breaks the seeds down so it is less likely to be in the manure. Cattle and other animals with a ruminant digestive systems have to eat twice as much of this weed to become ill due to the high level of efficiency this manner of digestion provides via ruminal metabolism.
CI's toxicity also SPIKES when it is STRESSED- either by cold snap, drought etc. So, while your horses may have survived last year with access to the weed... THIS YEAR could be different.
Creeping Indigo contains two toxins:
3-nitropropionate (3-NPA) - A highly toxic compound, produced by the plant primarily as defense against destruction by herbivores. The toxin is a potent and irreversible inhibitor of mitochondrial succinate dehydrogenase, a key enzyme in transforming glucose and oxygen into useable energy. Nerve cells are extremely vulnerable to energy deprivation, thus accounting for the early and prominent neurologic signs seen with all types of 3-NPA toxicity. Because it is metabolized quickly, it is unlikely to be found in the serum of affected animals.
Indospicine - A non-protein amino acid. It is toxic to the liver because of antagonism to the essential amino acid arginine, with which it competes. It is a CUMULATIVE toxin meaning: it builds in their system over a LIFETIME and persists, even after, removal from the weed. One of its principal toxic actions is inhibition of nitric oxide synthase, an action likely associated with the development of corneal edema and ulceration of mucous membranes. Although horses are relatively resistant to the liver damaging effects of this toxin, it persists in the tissues of horses dying or killed with the disease and these tissues are potentially toxic. Indospicine CAN BE detected in the serum of affected animals however, that test is not currently included in U.S. toxicology panels.
How much has to be consumed in order to cause illness has not yet been studied and or published.
UF has discussed that they also believe the unusually warm winters we have had in FL the last few years (2012-2014) may be a huge contributing factor to the spike of outbreaks we are experiencing currently. It seems the weed has reached full saturation of the state, with the exception of properties that have been treated with effective herbicides consistently.
Also, you must consider that as horses eat this weed- they are re-seeding it. So, as the years/months go on- the quantity and availability of CI increases. Because, a horses digestive track is less efficient than cows and can help SPREAD the seeds.
A cow's digestive system (ruminant) breaks the seeds down so it is less likely to be in the manure. Cattle and other animals with a ruminant digestive systems have to eat twice as much of this weed to become ill due to the high level of efficiency this manner of digestion provides via ruminal metabolism.
CI's toxicity also SPIKES when it is STRESSED- either by cold snap, drought etc. So, while your horses may have survived last year with access to the weed... THIS YEAR could be different.
Creeping Indigo contains two toxins:
3-nitropropionate (3-NPA) - A highly toxic compound, produced by the plant primarily as defense against destruction by herbivores. The toxin is a potent and irreversible inhibitor of mitochondrial succinate dehydrogenase, a key enzyme in transforming glucose and oxygen into useable energy. Nerve cells are extremely vulnerable to energy deprivation, thus accounting for the early and prominent neurologic signs seen with all types of 3-NPA toxicity. Because it is metabolized quickly, it is unlikely to be found in the serum of affected animals.
Indospicine - A non-protein amino acid. It is toxic to the liver because of antagonism to the essential amino acid arginine, with which it competes. It is a CUMULATIVE toxin meaning: it builds in their system over a LIFETIME and persists, even after, removal from the weed. One of its principal toxic actions is inhibition of nitric oxide synthase, an action likely associated with the development of corneal edema and ulceration of mucous membranes. Although horses are relatively resistant to the liver damaging effects of this toxin, it persists in the tissues of horses dying or killed with the disease and these tissues are potentially toxic. Indospicine CAN BE detected in the serum of affected animals however, that test is not currently included in U.S. toxicology panels.
How much has to be consumed in order to cause illness has not yet been studied and or published.