This proposal initiated from industry’s enquiry to investigate supoptimal growth performance in broiler chickens offered diets with droughtstressed sorghum. With a variable climate, drought has been a constant and inevitable feature of the Australia landscape. The current drought began in NSW in mid 2017 and it is equivalent to a major drought event on the long term historical record (100 years) according to NSW Department of Primary Industry. Consequently, this led to reduction of grain harvest and increase of grain price by more than 50% for chickenmeat producers. Sorghum has been routinely used in poultry diets in Eastern States to substitute wheat when there is a $20/MT price difference in comparison to wheat. Due to the shortage of wheat grains and its premium price this year, sorghum has been used in broiler diets with high inclusion rates (>50%). Surprisingly, growth performance in broiler chickens offered droughtstressed sorghum was depressed and the reduction of growth did not justify the price advantages in sorghum. It is also of concern the existing Nearinfrared spectroscopy (NIRs) calibrations failed to detect droughtstressed sorghums as outliers, which means other antinutritive factors need to be identified and included in the calibration. The present project will evaluate nutrient utilisation and growth performance in broiler chickens offered sorghum grains planted under different weather conditions. Meanwhile, sorghum grains will be collected from the industry opportunistically for wet chemistry analyses and development of NIRs calibrations from 20202023. A Barley trial will also be conducted.The feeding study will compromise eight dietary treatments (Table 1). Each treatment will be replicated 6 times with 18 birds per replicate. Wheatsoybean meal diets (containing both canola meal and seeds consistent with commercial practice) will be formulated to meet birds’ nutrient requirements based on breeder recommendations.
The University of Sydney
The primary goal of this project is to identify potential antinutritive factors in droughtstressed sorghum and how they compromise growth performance in broiler chickens. It is proposed to run for 3.5 years collecting 30 sorghum samples from the industry and conduct 5 feeding studies in both metabolic cage and deep litter systems. The specific objectives are, Aim 1: Measure the influence of climate on nutrient profiles in sorghum, including starch content, amino acid profiles, kafirin, minerals and phenolic compounds. Aim 2: Evaluate the influence of sorghum varieties and growing conditions on growth performance, carcass yields and nutrient utilisations in broiler chickens Aim 3: Determine the influence of sorghum growing conditions and inclusion rates on growth performance, carcass yields and nutrient utilisations in broiler chickens offered wheatbased diets Aim 4: Determine the efficacy of protease and phytase and the feasibility of reduced CP diets in broiler chickens offered diets based on droughtstressed sorghum. Aim 5: Conduct a Barley Trial comprised of 8 dietary treatments and report on: o Growth performance o Feed conversion ratio o Digesta samples taken to determine viscosity and water content.
Project Start Date
Wednesday, September 30, 2020
Project Completion Date
Thursday, February 29, 2024
Journal Articles From Project
An environmentally sustainable Australia
Adoption of R&D
CME-Improve chicken meat production through the whole supply chain