EFFECT OF DIETARY INCLUSION LEVELS OF DIATOMACEOUS EARTH ON PRODUCTION AND CARCASS CHARACTERISTICS OF BROILERS

Published Thesis

This study was done to investigate the effect of diatomaceous earth (DE) inclusion levels on the growth performances and carcass quality characteristics of broilers. A total of 750 as-hatched day-old Arbor Acres broiler chicks were randomly allocated to five experimental treatments (n=150 birds/treatment). A standard commercial broiler diet consisting of a three phase feeding regimen (Starter: D0-16, Grower: D17-35 & Finisher: D36-42) was used during the experimental period as the control diet (0% DE inclusion). All the broilers received the control diet for the first 16 days, without any additional DE supplementation. From D17 onwards (25 day period), birds received their respective experimental diets whereby the DE was mixed with the control diet at respectively 0.5%, 1.0%, 1.5% and 2.0% inclusion levels. Feed and water provision was at an ad libitum basis throughout the experimental period, whereas a photoperiodic period of 18 hr light and 6 hr darkness (18H:6D) were used. Brooding temperature was gradually decreased from 33 ˚C (D0) to 24 ˚C on D21 of age, while birds were housed on pine wood shavings at a floor density of 11.5 birds/m2. At D42 of age, 24 birds/treatment (n=12♂ & 12♀/treatment) were fasted overnight before being weighed and slaughtered. Internal organs such as the heart, gizzard and liver weights were recorded after evisceration of the carcasses, while carcasses were cut into eight-piece portions to determine the effect of DE inclusion on carcass characteristics. Data were statistically analysed (P <0.05) using a fully randomised one-way ANOVA procedure. Treatment 5 (2.0% DE inclusion) resulted in the highest (P <0.05) feed conversion ratio (FCR) (2.07) and the lowest (P <0.05) performance efficiency factor (PEF) (272). In general, it can be concluded that dietary DE inclusion level had no effect (P >0.05) on most of the production and carcass quality traits. The results of the present study suggest that the inclusion of up to 1.5% DE in broiler diets during the growing and finishing phases will not have (P >0.05) a negative effect on broiler production parameters and carcass quality characteristics.