Enzyme Profile in Blood and Tissues of Chickens Fed Various Levels of Monensin

Abstract

SummaryThe influence of recommended prophylactic doses or overdosages of moiiensin on growth and on enzymatic activities in blood and in various organs of 5 — 8 week old broiler chickens was investigated. Feeding of 300 or 400ppm monensin in the ration caused a reduction of feed consumption, paralysis, a 13—20% mortality and a retardation in body weight gain of the survivors. A tendency to recovery, probably as a result of gradually acquired tolerance, was evident in the second week of monensin feeding. Considerable incre.ise in the activities of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), creatine phosphokinase (CPK) and malic enzyme (ME) occurred in plasma as influenced by toxic levels of monensin. Significant increases in alkaline phosphause (ALP), AST and alanine aminotransferase (ALT) activities were recorded in the liver and to a lesser extent in thigh muscle at 400 ppm monensin, but the activity of cardiac CPK was significantly decreased. Tlie prophylactic dose of 100 ppm monensin affected those enzymes involved in key met.ibolism, such as LDH, MDH and AST, most evidently after 5 days of feeding.