The main cause of alimentary dystrophy is insufficient and inadequate feeding of horses, especially in winter and spring. Тhe availability of forage the fееding units and digestive protein has bееn respectively 38,9 and 39,8 %. The deficiency of intake by forage the feeding nutrients (proteins, fats, carbohydrates, vitamins and minerals) causes the removal it through their own body reserves. First of all, mobilizes the liver and muscle glycogen for cover energy expenditures. However glycogenolysis rapidly decays because the glycogen supaies suffice only a few days, later fat stores spended. According to studies researching group which was presented belongs to the first level of severity of illness. The animals observed total inhibition (flabby movements, lowered head), dull and disheveled hair. The conjunctiva has been anemic color in 85% of horses, capacity for work in animals has been reduced. The level of total protein in the group of horses with nutritional dystrophy have been amount to 62,2±1,38 g/l average, which is reliable lower than in clinically healthy (73,2±1,10 g/l). Hypoproteinemia was founded in 73,3 % of animals which was due through insufficient intake of protein by them. The quality structure of protein, has been changed, particularly content albumines. Their level in blood serum of 66,6 % sic horses have been reduced to 20,4±1,36 g/l or 33,4±1,56 % of total protein, which is probably less than in animals of second group. Presence of dysproteinemia confirmed by colloidaly sediment reactions: for precipitation the blood serum proteins spent 1,5–1,9 ml of 0,1 % solution of mercuric chloride. Dysproteinemia was founded in 100 % of reseached animals. The objective indicators of estimate the functional state and structure of liver and other organs, including the pancreas, are determineted the activity of aminotransferases (AST and ALT ), α–аmylase and gamma–glutamyl transpeptidase (GGT). In 47 % of sick horses we have established hyperenzymemia AST (>1000 nkat/l). The other 53 % of the animals had enzyme activity in the upper limit of normal (960 nkat/L), their limits were 960,0–1100,0 , average activity of enzyme – 978,0 ± 11,99 nkat/l, which is reliably higher than in clinically healthy animals (p < 0,001). The activity of ALT, in difference of AST, unlike in horses with nutritional dystrophy has been within the physiological limits, it's average activity in this group was 66,1±7,3 nkat/l, which does not probably differ from the values in clinically healthy horses. Similar results were found in determination of GGT. The activity of α–amylase in serum of sick animals was on average 5,6±0,74 mg/(sxl), which was higher than the maximum limit of normal 4,41 mg/(sxl). The increased of activity enzyme was founded in 60% of animals. One of the important marker of the state of pancreas is the level of glucose in the blood, which in healthy animals is constant. We founded that level of glucose in the blood serum of clinically healthy horses an average amount to 3,3±0,11 mmol/l (lim 2,6–4,0), it has been higher in sick (4,55±0,17 mmol/l). Thus increasing the activity of α-amylase enzyme noted in 60% of animals. In 73,3 % of animals there was founded hypoproteinemia, 66,6– hypoalbuminemia, 100 % – dysproteinemia. According to the results hyperenzymemia AST is observed in 47% of horses.

Key words: horses, pancreas, nutritional dystrophy, liver, enzyme α-amylase, АsАТ, АlАТ, GGТP.