Abstract
Abstract: The poultry industry's goal is to find alternatives to conventional protein feed resources to maximize the poultry venture's profit. One of these alternatives is mulberry (Morus Alba) leaf powder (MLP). In this study, we determined the effect of MLP inclusion in quail diet on growth performance, economic efficiency, bacterial count, oxidative stress and immunity. A total of 288 seven-day-old chicks of Japanese quails (white and brown strains) were obtained from local Egyptian hatcheries, were accommodated for one week, and fed on a basal diet. On the 14th day, chicks were weighted, wing banded, housed in cages, and distributed randomly into three iso-energetic and iso-nitrogenous diets (triplicate/group, 16 bird/replicate, 48 bird/ group). Diets formulated to contain MLP at levels of 0 (control), 4, and 8%, respectively, for each strain from 14 to 42 days of age. Our results showed that the inclusion of MLP up to 8% resulted in a non-significant change on growth performance parameters (final body weight, cumulative body weight gain, and dressing percentage), economic efficiency (total return, gross margin, and benefit-cost ratio), and relative economic efficiency parameters comparing with 0% MLP diet. Additionally, inclusion of MLP up to 4% in both Japanese quail strains showed a non-significant decrease in the cost of each kg body weight gain from the feed. Increasing MLP levels up to 8% in the diet resulted in a non-significant effect on immunoglobulin G in both strain and a significant increase in interleukin 2 & 6. in brown Japanese quail. Superoxide Dismutase activity and catalase enzyme activity showed a non-significant decrease in groups of white strain-fed diets with 4 & 8% MLP than those fed diets with 0% MLP. Inclusion of MLP 8% recorded a significant decrease in the total aerobic count, E.coli and clostridia count, with a non-significant effect on lactobacillus count in both quail strains and antibody titer against Newcastle virus vaccine. We concluded that MLP can be included in the diet up to 8% without adverse effect on growth parameters, economic measures, no oxidative stress and no alteration in bird immunity.

Key words: Keywords: Quail; Growth; Gut microbiota; Mulberry leaves; Feed cost; Immunoglobulin.