Bhagavatapurana 12.2.14

12.2.14

śūdra-prāyeṣu varṇeṣu cchāga-prāyāsu dhenuṣu /
gṛha-prāyeṣv āśrameṣu yauna-prāyeṣu bandhuṣu //

14. When the (three) Varnas become Sudras, when cows get transmuted into sheep, when the four asramas get converted into households, when the relatives are no other than wive's relations;