ThePigSite Pig Health
Electrolytes(157) Approximately 55% of a pigs body weight is made up of water. In young lean animals it is much higher (70%) and in fat ones lower because fat contains little water.
The fluid balance in the body is regulated by the kidney and in particular the concentrations of sodium (Na), chloride (Cl), potassium (P), hydrogen ions, bicarbonate, protein, calcium and magnesium in the tissues. These substances are called electrolytes.
A pig could loose 5% of its body weight in fluid losses with little clinical effect but at 15% it would die.
Such losses equate to 40-160ml/kg of body weight. If the pig cannot maintain its fluid balance by intake relative to normal or abnormal losses dehydration will result.
Diarrhoea and vomiting are by far the most important causes in the young pig particularly during sucking and in the immediate post-weaning period.
Certain types of E. coli and salmonella produce toxins which cause fluids to be excreted into the small intestine. This is called secretory diarrhoea.
Conversely viral infections such as TGE virus, PED virus and rotavirus destroy the villi in the intestine causing a marked reduction in the absorptive capacity of the digestive system and dehydration. This is called malabsorption or osmotic diarrhoea. It is also common in a milder form in pigs that have been weaned 2 days or more. It may then occur with or without diarrhoea.