Agustini, M.A.B. et al. 2014. Nutritional levels of digestible threonine in brown-egg laying hens from 75 to 90 weeks of age. Semina: Ciências Agrárias. 35, 6 (dez. 2014), 3449–3456. DOI:https://doi.org/10.5433/1679-0359.2014v35n6p3449.