en Toxicology Toxicology پژوهشي Orginal research papers <p>  The acute toxicity and effects of diazinon on some haematological parameters of kutum (<i>Rutilus frisii kutum</i>, Kamensky, 1901) weighing 613.33 ± 157.06 g were studied under static water quality conditions at 15 °C ± 2 ºC. These experiments were carried out based on the standard TRC, 1984 method over 4 days, and controlled for the effective water physicochemical factors having pH rangesof 7-8.2, total hardness 300 mgl^-1 (caco₃), dissolved oxygen 7 mgl^-1. The results showed that the 96h LC₅₀ value of diazinon was 0.4 mgl^-1 and that the maximum allowable concentration (MAC) value of this toxin was 0.04 mgl^-1. The second stage of experiments consisted of four treatments: LC₀: 0 as blank, treatment A with a concentration of LC₁: 0.107 mgl^-1, treatment B with a concentration of LC₅: 0.157 mgl^-1, treatment C with a concentration of MAC value: 0.04 mgl^-1. Male brood stocks of <i>R. frisii </i>were treated with these concentrations for 45 days. The results showed that long-term exposure to diazinon causes a decrease in the erythrocyte count (RBC), haemoglobin (Hb), haematocrit (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), leucocyte count (WBC), lymphocyte, testosterone, iron (Fe), sodium (Na), lactate dehydrogenase (LDH) and cholinesterase (CHeS) (P<0.05). Diazinon also causes an increase in prolymphocyte, aspartate aminotransferase (AST), cholesterol, alkaline phosphatase (ALP) and adrenaline (P<0.05). There are no significant effects on monocyte, eosinophil, <strong>magnesium </strong>(Mg), chloride (Cl), glucose (BS), urea (BUN), <strong>uric </strong><strong></strong><strong>acid (U.A) </strong><strong>,</strong> triglyceride (TG), <strong>calcium </strong>(Ca), albumin (Alb), total protein (TP), <strong>cortisol </strong>, noradrenaline and high density lipoprotein (HDL) levels in <i>R. frisii </i>male brood stocks (P>0.05). The results showed that long-term exposure to low concentrations of diazinon causes changes in some haematological and biochemical parameters of <i>R. frisii </i>male brood stocks <strong>. </strong></p> Diazinon, Haematological, Biochemical, Rutilus frisii kutum 105 117 http://jifro.ir/browse.php?a_code=A-10-1-141&slc_lang=en&sid=1 M. Mohammad Nejad Shamoushaki Majid_m_sh@yahoo.com 10031947532846002691 10031947532846002691 Yes M. Soltani 10031947532846002692 10031947532846002692 No A. Kamali 10031947532846002693 10031947532846002693 No M. R. Imanpoor 10031947532846002694 10031947532846002694 No I. Sharifpour 10031947532846002695 10031947532846002695 No H. Khara 10031947532846002696 10031947532846002696 No