[Long-term exposure of broiler chick to PCB--clinical and biochemical changes].
In view of preventive human and veterinary medicine negative effects of PCB are serious mainly with respect to their stability in food chain. A low degree of biotransformation in living organisms and PCB transfer through food chain have resulted in the ban on PCB production and in restriction of their use. Important restriction measures concerning the use of PCB-based products were already taken in the eighties. In spite of the ban on PCB production in this country (1984), their inventories along with contaminated refuse make around 10,000 tons. The data indicate the existence of sources of food chain contamination. Information campaign as well as targeted PCB monitoring are important components of prevention of environmental contamination. The originally monitored PCB sum has currently been replaced by a system of monitoring oriented to particular PCB congeners. The objective of this paper is to present clinico-biochemical changes observed in broiler chicks after a long-range exposure to a relatively low rate of original commercial types of PCB. Sixty one-day cockerels Hybro (paternal line) were included in a trial. The chicks were housed in boxes with deep litter under continuous lighting. They had free choice of feed and water. Control and experimental groups contained 30 broiler chicks each. A PCB blend (Delor 103 and Delor 105--original commercial products of PCB from Chemko Strázske) were added at a concentration of 50 mg/kg feed to the diet of experimental group. Numerous clinical and biochemical parameters were investigated in the conditions of long-range applications (1-42 days).(ABSTRACT TRUNCATED AT 250 WORDS)