The aim of this study was to monitor the biochemical and chemical parameters of the blood of commercial chickens following treatment with one of three coccidiostats: maduramycin, monensin or diclazuril. Chickens received feed treated with maduramycin at concentrations of 5, 10 and 15 mg kg-1, monensin at 125, 225 and 325 mg kg-1 or diclazuril at 1, 5 and 10 mg kg-1. A control group of chickens consumed feed without the addition of coccidiostats. Following treatment, blood was sampled for 11 days and analysed for the following biochemical and chemical parameters: aspartate aminotransferase (AST), bile acid (BA), creatine kinase (CK), uric acid (UA), glucose (GLU), cholic acid (CA), total protein (TP), albumin (ALB), globulin (GLOB) and phosphorus (PHOS). Administration of different concentrations of maduramycin, monensin and diclazuril did not affect the concentration of the parameters AST, UA, GLU, BA, TP, ALB, GLOB and PHOS in experimental groups of broilers in relation to the control group. However, significant differences were observed in the concentrations of CK and CA between the experimental and control groups. Significant differences were also found in the concentrations of AST, CA and UA between experimental groups. Key words: maduramycin; monensin; diclazuril; chickens; biochemical and chemical parameters   SPREMEMBE BIOKEMIJSKIH IN KEMIJSKIH PARAMETROV V KRVI KOKOŠI PO ZDRAVLJENJU Z MADURAMICINOM, MONENZINOM IN DIKLAZURILOM Namen raziskave je bil spremljanje biokemijskih in kemijskih parametrov krvi industrijsko gojenih piščancev po zdravljenju z enim od treh kokcidiostatikov: maduramicinom, monenzinom ali diklazurilom. Piščanci so dobivali krmo z maduramicinom v koncentracijah 5, 10 in 15 mg/kg, monenzin v koncentracijah 125, 225 in 325 mg/kg ali diklazuril v koncentracijah 1, 5 in 10 mg/kg. Kontrolna skupina piščancev je dobila krmo brez dodatka kokcidiostatikov. Enajsti dan po zdravljenju je bila piščancem odvzeta kri in analizirani so bili naslednji biokemijski in kemijski parametri: koncentracija aspartatne aminotransferaze (AST), žolčnih kislin (BA), kreatininske kinaze (CK), sečne kisline (UA), glukoze (Glu), skupnih beljakovin (TP), albuminov (ALB), globulinov (GLOB) in fosforja (Phos). Dodajanje različnih koncentracij maduramicina, monenzina in diklazurila ni vplivalo na koncentracijo parametrov AST, UA, Glu, BA, TP, ALB, GLOB in Phos v poskusnih skupinah pitovnih piščancev v primerjavi s kontrolno skupino. Statistično značilne razlike so bile ugotovljene v koncentracijah CK in CA med poskusnimi in kontrolno skupino. Značilne razlike so bile ugotovljene tudi v koncentracijah AST, CA in UA med posameznimi poskusnimi skupinami. Ključne besede: maduramicin; monenzin; diklazuril; piščanci; biokemijski in kemijski parametri