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Ponies suffering from chronic laminitis would benefit from dietary supplementation with anti-oxidants. New research indicates that high levels of free radicals are found in ponies with chronic laminitis.
Free radicals are highly reactive particles produced as the result of reduced perfusion or released as part of the inflammatory process. They can react with tissues locally (at the site of release) or throughout the body, resulting in tissue damage. They are thought to play a significant role in the ageing process.
Although free radicals form a normal part of the inflammatory process, if present in excess they can
Free radicals are highly reactive particles produced as the result of reduced perfusion or released as part of the inflammatory process. They can react with tissues locally (at the site of release) or throughout the body, resulting in tissue damage. They are thought to play a significant role in the ageing process.
Although free radicals form a normal part of the inflammatory process, if present in excess they can
Oxidative stress in chronic laminitis
cause damage to the tissue itself, resulting in a state known as "oxidative stress". Oxidative stress can be quantified by measuring the products that result from free-radical activity. One way of doing this is to measure TBARS (thio-barbituric acid reactive substances) in the urine.
A research team, headed by Dr Rachel Neville at the University of Lincoln, compared the concentration of TBARS in the urine of normal ponies and those with chronic laminitis. They reported their findings in the April issue of Equine Veterinary Journal.
Two groups of native ponies from an equine sanctuary were used for the study. The first group comprised twenty ponies with physical signs of chronic laminitis (alteration in foot shape with dropped soles). The ponies in the second group were apparently normal and had no history of previous laminitis. The average age of ponies in the two groups was similar. Urine samples were collected from each pony and frozen until analysed.
The concentration of substances in the urine is influenced by the amount of water present. The results were expressed as a ration of the concentration of creatinine in the urine. The body produces creatinine at a relatively constant rate. So this provides a way of taking into account how dilute the urine is and standardising the results.
The researchers found that the concentration of TBARS in the urine of ponies with chronic laminitis was three times higher than that of normal ponies. It was particularly interesting that the laminitic ponies had high levels of free radicals despite not being lame at the time.
They suggest a number of possible explanations for the high levels of free radicals in the laminitic ponies. Reduced blood supply and inflammation in the laminae could be responsible, but as the ponies were not lame it seemed less likely. Peripheral Cushing's disease (metabolic syndrome), in which the glucose and insulin metabolism is disturbed, can lead to laminitis and is associated with free radical production.
It is likely that several factors are involved and further investigation is warranted to clarify the situation.
The findings have implications for the nutrition of ponies with chronic laminitis. Teresa Hollands of Dodson and Horrell, one of the researchers, advises that all horses and ponies suffering from laminitis should be fed appropriate levels of antioxidants including plant based anti-oxidants, anti-oxidant vitamins A and C m and anti-oxidant minerals selenium and copper.
Reference: Evaluation of urinary TBARS in normal and chronic laminitic ponies. RF Neville, T Hollands, SN Collins, FV White Equine Veterinary Journal (2004) 36, 292-294.
A research team, headed by Dr Rachel Neville at the University of Lincoln, compared the concentration of TBARS in the urine of normal ponies and those with chronic laminitis. They reported their findings in the April issue of Equine Veterinary Journal.
Two groups of native ponies from an equine sanctuary were used for the study. The first group comprised twenty ponies with physical signs of chronic laminitis (alteration in foot shape with dropped soles). The ponies in the second group were apparently normal and had no history of previous laminitis. The average age of ponies in the two groups was similar. Urine samples were collected from each pony and frozen until analysed.
The concentration of substances in the urine is influenced by the amount of water present. The results were expressed as a ration of the concentration of creatinine in the urine. The body produces creatinine at a relatively constant rate. So this provides a way of taking into account how dilute the urine is and standardising the results.
The researchers found that the concentration of TBARS in the urine of ponies with chronic laminitis was three times higher than that of normal ponies. It was particularly interesting that the laminitic ponies had high levels of free radicals despite not being lame at the time.
They suggest a number of possible explanations for the high levels of free radicals in the laminitic ponies. Reduced blood supply and inflammation in the laminae could be responsible, but as the ponies were not lame it seemed less likely. Peripheral Cushing's disease (metabolic syndrome), in which the glucose and insulin metabolism is disturbed, can lead to laminitis and is associated with free radical production.
It is likely that several factors are involved and further investigation is warranted to clarify the situation.
The findings have implications for the nutrition of ponies with chronic laminitis. Teresa Hollands of Dodson and Horrell, one of the researchers, advises that all horses and ponies suffering from laminitis should be fed appropriate levels of antioxidants including plant based anti-
Reference: Evaluation of urinary TBARS in normal and chronic laminitic ponies. RF Neville, T Hollands, SN Collins, FV White Equine Veterinary Journal (2004) 36, 292-
Report by Mark Andrews.