Shemil Macelline

In previous assays (Macelline et al., 2022), data on egg production rate (EP) and egg mass (EM) of Isa Brown layers from 27 to 33 weeks of age (peak production -PP) and from 42 to 48 weeks of age (Post PP) were used to predict amino acid (AA) requirements by fitting linear broken-line (LBL), and quadratic broken-line (QBL) models. Subsequently, the ideal ratios of Ile, Met + Cys, Thr, Trp, and Val ...

All grains, vegetable-based protein meals and their by-products used in poultry diets contain some levels of phytate phosphorous (PP). Depending on the ingredient type and source, a typical broiler chicken diet would contain between 2.2 to over 3.5 g/kg dietary PP. Research has shown that phytate anti-nutritional effects can reduce the digestibility of amino acids (AA) and minerals. Previously the ...

I. INTRODUCTIONThe term ‘amino acid imbalances’ was probably originated by Elvehjem and Krehl (1955) and the topic was addressed by Harper and Rogers (1965). Their conclusion was that imbalances retard growth by altering the normal pathways of amino acid metabolism. Thus, while the relevance of amino acid imbalances to efficient chicken-meat production is recognised, a precise definiti ...

I. INTRODUCTIONMannan is a plant based-NSP derived from polymerisation of mannose sugars, it is categorised as galactomannan or glucomannan based on the presence of galactose and glucose side chains (Aspinall, 1973). Generally, galactomannan is the dominant form in legumes (Sundu et al., 2012). The ratio between mannose to galactose dictates the water solubility of galactomannan where galactose ha ...

I. IntroductionWheat and sorghum are the two major feed grains used in Australia for broiler diets; however, wheat is more common and is usually considered better quality than sorghum. The local chicken meat industry may have to increase by 60% to meet demand in 2050 so strategies are needed to promote sustainable chicken-meat production to meet this anticipated demand. Crude protein reductions in ...

1. IntroductionThe global demand for chicken-meat is increasing. Globally, poultry meat is expected to represent 41% of all the protein from meat sources in 2030 and exceed the 34% share for pig meat, 20% for beef and 5% for sheep meat [1]. In Australia, the 46.9 kg per capita chicken-meat consumption in 2021/22 is clearly superior to pork (27.7 kg), beef (19.1 kg) and lamb (5.5 kg) with a 47.3% m ...

I IntroductionIn recent years, based on ideal amino acids profile, a moderate reduction in dietary CP, 20 to 30 g/kg, has been reported to maintain broiler chicken performance and processing yields. However, further reduction of CP more than 30 g/kg has been shown to compromise bird performance and increase adipose fat accumulation (Kidd et al, 2021). These reduced CP levels are usually achieved b ...

I IntroductionThe development of reduced-crude protein (CP) diets for broiler chickens holds several potential advantages including reduced dependency on imported soybean meal by the Australian chicken-meat industry. Typically, reduced-CP diets contain less soybean meal but more feed grain (and starch) and more synthetic/crystalline amino acids. However, reducing dietary CP from 200 to 150 g/kg in ...