Srimad Bhagavatam Canto 11, Chapter 17, Text 24

SB 11.17.24

snana-bhojana-homesu
 japoccare ca vag-yatah
na cchindyan nakha-romani
 kaksopastha-gatany api
 
Translation: 
 
A brahmacari should always remain silent while bathing, eating, attending sacrificial performances, chanting japa or passing stool and urine. He should not cut his nails and hair, including the armpit and pubic hair.
 
Purport: 
 
Narada Muni gives a similar technical description of Vedic brahmacari life in Canto Seven, Chapter Twelve, of Srimad-Bhagavatam.
Srimad Bhagavatam Canto 11, Chapter 17, Text 23
Srimad Bhagavatam Canto 11, Chapter 17, Text 25