Streptococcosis outbreaks occur in a wide range of farmed fish species, globally (Mishra et al., 2018). Outbreaks in farmed freshwater tilapia continue to threaten global production, contributing to severe economic losses encountered worldwide (Amal & Zamri-Saad, 2011;

There is a need to search for solutions of minimizing aggression so as to minimize violence. The purpose of the study is to determine the effects of different levels of egg albumin supplementation to the aggressive behavior of male white mice (Mus musculus). Specifically, this study aimed to describe aggressive tendencies by isolation-induced fighting of male white mice when fed different levels of egg albumin; determine aggressive behavior in terms of the number of attacks and body scars when fed different levels of egg albumin; and measure dominant-subordinate status when fed different levels of egg albumin. White mice were chosen as test animals since they have homologous genes coding with humans. Furthermore, aggression tends to be more common among male mice than female mice. T-test results showed that there is a significant difference in the aggressive behavior between the treated and untreated mice in all treatments except for Treatment D (negative control) in terms of number of attacks and body scars and a significant difference in all treatments in terms of the dominant-subordinate status. Analysis of Variance (ANOVA) showed a significant difference in the number of attacks and the dominant subordinate status. Overall, results showed that egg albumin supplementation reduced aggression in male white mice regardless of the level of egg albumin. It was concretely shown that treatments fed with varied levels of egg albumin significantly alleviated aggressive behavior compared with treatments without egg albumin supplementation.