The transition period for dairy cows has been highlighted as the period of time where cows are most susceptible to metabolic disorders due to the strong nutrient demands from lactation (Drackley, 1999). This leads to negative energy balance and cows must mobilize their tissue reserves to compensate for the difference, which can cause immune dysfunction and lead to disorders such as hyperketonemia and mastitis (Overton and Waldron, 2004). Hyperketonemia is defined as a concentration of β-hydroxybutyrate ≥1.2 mmol/L in blood and a case is estimated to cost a farmer up to $289 (McArt et al., 2015). The branched-chain amino acids (BCAA) leucine, isoleucine, and valine are all essential amino acids (AA) cows must obtain through their diet or microbial protein synthesis to meet daily requirements. BCAA are unique compared with other AA because they are not directly metabolized by the liver. Branched-chain aminotransferase (BCAT2), the first enzymatic step in the oxidation of BCAA shows higher activity in muscle tissue than in liver (Herman et al., 2010). Leucine plays a particularly important role in activating the signaling factor of the mammalian target of rapamycin (mTOR) pathway to promote protein synthesis in skeletal muscle. Previous studies have shown the mTOR pathway results in decreased food intake by stimulating leptin release and improving glucose metabolism (Herman et al., 2010; Laplante and Sabatini, 2012). Studies in lactating dairy cows have shown no significant difference in milk protein yield, milk volume yield, or changes in the milk profile with BCAA supplementation (Appuhamy et al., 2011; Mackle et al., 1999; Huhtanen et al., 2002). Thus, indicating that BCAAs play a role in muscle protein synthesis with a particular emphasis on leucine (Mackle et al., 1999). By supplementing BCAAs in the early postpartum diet, there is an opportunity to reduce the negative energy balance by stimulating skeletal muscle tissue synthesis through the BCAA mTOR pathway.