Effects of light intensity in different stocking densities on tibial measurements and incidence of lesions in broilers

Abstract

Abstract: The possibility for use of high light intensity in broiler production management to improve the health of broilers’ legs was examined in a study aiming to determine the effect of two levels of light intensity in different stocking densities of broiler chickens. The study was carried out on 1200 Ross 308 broilers according to a random block system with 6 treatments (2 x 3 factorial design) and 4 replicates per treatment. The examined light intensity levels of 150 lx (high light intensity-HLI) and 20 lx (low light intensity-LLI) were applied to 3 stocking densities of broilers: 10, 13 and 15 birds/m2 . Scoring of foot pad (FP) and hock burns (HB) was carried out on the 42nd day, on a sample of 240 broilers. Osteometric and biomechanical measurements on tibia were performed after slaughtering and primary processing, on a sample of 72 broilers. The high level intensity of light exerted no significant effect on the development and firmness of the tibia of broilers grown in the densities of 10, 13 and 15 birds/m2 . There are indications that in the highest studied stocking density the increased light intensity can improve the individual properties of tibia. The differences in the average assessment of hock burns were concluded to be the result of the stocking density that was observed only in conditions of the increased intensity of light. The average score of foot pad lesions was under the significant main effect of both investigated factors. The differences in the average FP estimation between the light intensity treatments were confirmed in the stocking density of 13 birds/m2.

Rezime:Mogućnost upotrebe svetlosti jačeg intenziteta u menadžmentu brojlerske proizvodnje za poboljšanje zdravlja nogu brojlera, ispitana je u ogledu sa ciljem utvrđivanja efekta dva nivoa intenziteta svetlosti u različitim gustinama naseljenosti brojlerskih pilića. Istraživanje je sprovedeno na 1200 Ross 308 brojlera po slučajnom blok sistemu sa 6 tretmana (2 x 3 faktorijalni ogled) i 4 ponavljanja. Ispitivani nivoi intenziteta svetlosti 150 lx (HLI) i 20 lx (LLI) su primenjeni u 3 gustine naseljenosti brojlera: 10, 13 i 15 birds/m2 . Procena lezija na tabanskom jastučiću (FP) i skočnom zglobu (HB) je izvršena 42. dana, na uzorku od 240 brojlera. Osteometrijska i biomehanička merenja na tibiji su izvršena nakon klanja i obrade, na uzorku od 72 brojlera. Svetlost jačeg intenziteta nije uslovila signifikantan efekat na razvoj i čvrstoću tibije brojlera gajenih u gustinama naseljenosti 10, 13 i 15 grla/m2 . Postoje indicije da u najvećoj ispitivanoj gustini naseljenosti, svetlost jačeg intenziteta može poboljšati pojedine osobine tibije. Razlike u prosečnoj oceni HB utvrđene su kao rezultat efekta gustine naseljenosti koji je ispoljen samo u uslovima jačeg intenziteta svetlosti. Prosečna ocena FP lezija je bila pod značajnim glavnim (main) efektom oba ispitivana faktora. Razlike u prosečnoj oceni FP između tretmana intenziteta svetlosti potvrđene su u gustini naseljenosti 13 grla/m2 .