The Effect of Yerba Mate (Ilex paraguarensis) Supplementation on the Productive Performance of Dorper Ewes and Their Progeny

Yerba Mate (Ilex paraguariensis), a tea known for its high antioxidant content, was supplemented to 30 of 60 ewes for 13 wks to assess its effect on their productive performance. A 2.5% inclusion rate of Yerba Mate (YM) in a pelleted concentrate diet decreased feed intake and live weight (LW) during the first few weeks post partum (p<0.001). Overall, the YM group ate less ($2,092{\pm}78g/d$) pellet than the control (CTRL) one ($2,434{\pm}83g/d$); similarly, LW was lower in the YM group compared to the CTRL one, $64.9{\pm}1.6kg$ and $67.3{\pm}1.4kg$, respectively. Lambs' birth weight and growth rates were not affected. At birth, lambs' LW were similar between the Yerba Mate and control groups ($4.2{\pm}0.5kg$ and $4.1{\pm}0.4kg$, respectively. At the end of the trial, Yerba Mate lambs weighed $15.7{\pm}0.4kg$ while CTRL lambs weighed $16.1{\pm}0.4kg$. Average daily growth rate was similar between the two groups and ranged from $176{\pm}19$ to $234{\pm}24g/d$. The inclusion of Yerba Mate in a pelleted diet increased milk fat, protein and total solids content while it decreased milk lactose content. Further work is required to investigate the mechanisms by which Yerba Mate supplementation affects feed intake and milk composition.