Srimad Bhagavatam Canto 11, Chapter 18, Text 07

SB 11.18.7

vanyais caru-purodasair
 nirvapet kala-coditan
na tu srautena pasuna
 mam yajeta vanasrami
 
Translation: 
 
One who has accepted the vanaprastha order of life should perform seasonal sacrifices by offering oblations of caru and sacrificial cakes prepared from rice and other grains found in the forest. The vanaprastha, however, may never offer animal sacrifices to Me, even those sacrifices mentioned in the Vedas.
 
Purport: 
 
One who has taken the vanaprastha order of life should never perform animal sacrifices or eat meat.
Srimad Bhagavatam Canto 11, Chapter 18, Text 06
Srimad Bhagavatam Canto 11, Chapter 18, Text 08