Śrī Caitanya Caritamrta · Text Ādi 17.163
কলিকালে তৈছে শক্তি নাহিক ব্রাহ্মণে ।
অতএব গোবধ কেহ না করে এখনে ॥ ১৬৩ ॥
kali-kāle taiche śakti nāhika brāhmaṇe
ataeva go-vadha keha nā kare ekhane
“Formerly there were powerful brāhmaṇas who could make such experiments using Vedic hymns, but now, because of the Kali-yuga, brāhmaṇas are not so powerful. Therefore the killing of cows and bulls for rejuvenation is forbidden.
Read this verse on Vedabase.ioThis verse has no purport; its meaning is explained by the verses around it.