अत ऊर्ध्वं चतुर्वर्षः पञ्चवर्षो वा कर्मण्यः पूर्णप्रमाणः ॥ कZ_०२.३०.१३ ॥
ata ūrdhvaṃ caturvarṣaḥ pañcavarṣo vā karmaṇyaḥ pūrṇa-pramāṇaḥ
从那时起,四岁——或作为另一选择五岁——即可用于役使,并应按足额标准(满额计)对待。
It builds administrative flexibility for differing breeds/conditions while still fixing a clear eligibility window for deployment and full rationing.