Influence of malted (Pennisetum glaucum) on the growth performance, carcass characteristics and economy of feed conversion of broiler chickens when used to replace maize in their diets

Abstract

Partly sprouted millet (Pennisetum glaucum) were incorporated into broiler chicken diets and used to evaluate their influence on the growth performance, carcass characteristics, sensory properties and the economy of feed conversion of broiler chickens. Six diets were formulated: Diet 1 consisted of a maize based diet and served as the control; Diets 2, 3, 4, 5 and 6 consisted of malted millet incorporated into the diets at 0 %, 25 %, 50 %, 75 % and 100 % respectively. A total of 216 day old CHI strain of broiler chicken were randomly allotted to the six diets, with each diet consisting of three replicates of 12 birds per replicate; making a total of 36 birds per treatment. The malted millet was prepared by washing cleaned millet grains with water, with excess water drained off, and then thinly spread on moistened jute sacks and then covered with moistened jute sacks. Water was sprinkled at an interval of four hours to keep the sacks and grains moist. These conditions were maintained in a well-ventilated room until the grains sprouted after 36 hours. At the end of the malting, the malted grains were sun dried in the open air for three days, milled to the required consistency using an attrition mill, and incorporated into the different diets. The diets were fed to the birds ad libitum for eight weeks and data collected on growth performance and economy of feed conversion. At the end of the feeding trial, one bird per replicate was randomly selected, slaughtered through cervical dislocation and analyzed for their carcass characteristics. The meat from each treatment was then evaluated for its sensory properties using a nine-point Hedonic scale. Data collected were analyzed using a one way analysis of variance, based on a completely randomized design model. Results showed that malting improved the protein content of the millet grains from 10.42 to 11.90 %; reduced the crude fibre content from 2.40 to 1.30 %; and reduced the nitrogen-free extracts from 82.39 to 78.00 %. Birds fed diet containing 50 % malted and 50 % unmalted millet recorded significantly (P<0.05) higher values in final body weight (1733.33 g) and body weight gain (1647.22 g). Birds fed malted millet diets had significantly (P<0.05) better feed conversion ratio (1.46 for T4 & T5) than the control diet (2.28). Dressed weight, weight of kidney, proventriculus, gizzard and heart were significantly (P<0.05) affected by the dietary treatments while weight of thighs, drumsticks, neck, back and breast; as well as weight of the rest of the organs and abdominal fat were not. The meat of birds fed the 50 % malted millet diet was significantly (P<0.05) more acceptable than those of the other diets. The feed cost per kg weight gain were significantly (P<0.05) lower for the malted millet diets than for the control diet. In conclusion, birds fed 50 % malted and 50 % unmalted millet diet had optimal weight gain, feed conversion ratio and sensory properties, when used as a replacement for maize, in broiler chicken diets.