St. Stoyanova*, Y.Staykov, G. Zelqzkov, I. Sirakov, G.Nikolov Department of Biology and Aquaculture, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria (Manuscript received 26 October 2016; accepted for publication 22 November 2016) Abstract. The rainbow trout (Onc

Т. Popova*, E. Petkov, M. Ignatova Institute of Animal Science, 2232 Kostinbrod, Bulgaria (Manuscript received 16 May 2015; accepted for publication 8 June 2016) Abstract. An experiment with two lines of chickens – synthetic line La Belle and White Plymouth Rock was carried out in the