Effects of intensity of light and stocking density on broiler body weight and yield of valuable carcass parts

Abstract

In order to determine the effect of intensity of light and stocking density, as well as the interaction of light intensity x stocking density on body weight and individual carcass traits, an experiment was performed on 1200 broilers of the Ross 308 genotype. The investigated factors were the intensity of light (LI): 20 lx (K) ; 150 lx (O) and stocking density (SD): 10 broilers/m2 (A); 13 broilers/m2 (B); 15 broilers/m2 (C), in 4 repetitions. The light source was incandescent bulbs of adequate intensity and a light program 16L: 4D: 2L: 2D was applied. Broiler body weight was controlled on 11th, 21st, 35th and 42nd day, by individual measurement of all chickens in the trial. The average sample containing 12 chickens per treatment with equal gender representation (total of 72 broilers) was used to study the slaughter quality of carcasses based on the parameters of absolute and relative yield of more valuable carcass parts (breast, thighs and drumsticks) and meat in the more valuable parts of the carcass. The effect of light with different intensity on the body weight differed depending on the broiler rearing phase. The interaction effect of the intensity of light and stocking density on the body weight of broilers was confirmed in all stages of growing up to the age of 42 days. A higher intensity of light (150 lx) showed the potential to alleviate the negative effects of higher stocking density (15 broilers/m2 ) on the final body weight of the broiler. The carcass traits were not significantly affected by the intensity of the light, while the stocking density, as well as the intensity of the light x stocking density did influence the yield of whole breast and the yield of breast meat.

U cilju utvrđivanja efekta intenziteta svetlosti i gustine naseljenosti, kao i interakcije intenzitet svetlosti x gustina naseljenosti na telesnu masu i pojedine karakteristike trupa, sproveden je ogled na 1200 brojlera genotipa Ross 308. Ispitivani faktori su intenzitet svetlosti (LI): 20 lx (K); 150 lx (O) i gustina naseljenosti (SD): 10 grlo/m2 (A); 13 grlo/m2 (B); 15 grlo/m2 (C), u 4 ponavljanja. Izvor svetlosti su bile incandescent bulbs odgovarajućeg intenziteta i primenjen je svetlosni program 16L:4D:2L:2D. Telesna masa pilića je kontrolisana 11., 21., 35. i 42. dana, pojedinačnim merenjem svih pilića u ogledu. Na prosečnom uzorku od 12 pilića po tretmanu sa podjednakom zastupljenošću polova (ukupno 72 brojlera) izvršeno je ispitivanje klaničnog kvaliteta trupa na osnovu parametara apsolutnog i relativnog prinosa vrednijih delova trupa (grudi, bataci i karabataci) i mesa u vrednijim delovima trupa. Efekat svetlosti različitog intenziteta na telesnu masu se razlikovao u zavisnosti od faze gajenja brojlera. Interakcijski efekat intenziteta svetlosti i gustine naseljenosti na telesnu masu brojlera je potvrđen u svim fazama gajenja do starosti 42 dana. Veći intenzitet svetla (150 lx) je pokazao potencijal da ublaži negativne efekte većih gustina naseljenosti (15 grlo/m2 ) na završnu telesnu masu brojlera. Karakteristike trupa nisu bile pod značajnim glavnim efektom intenziteta svetlosti dok je gustina naseljenosti, kao i interakcija intenzitet svetlosti x gustina naseljenosti, uticala na prinos celih grudi i prinos mesa grudi.