गोतो णित्

The endings of the strong cases are णित् after गो।
That is, these affixes produce all the णित् operations: such as Vriddhi &c. As गौः, गावौ, गावः ॥ Why have we added a त् after गो ? The rule applies to the form गो, and not when it assumes the form गु, as in चित्रगुः, शबलगुः ॥

How do you explain the forms हे चित्रगो, हे शबलगवः ? This is done on the maxim अङ्गवृत्ते पुनर्वृत्तावविधिर्निष्टितस्य, (when an operation which is taught in the Angadhikara (VI.4.-VII.4). has taken place, and another operation of the Angadhikara is subsequently applicable, this latter operation is not allowed to take place). For when Guna once takes place before the Vocative and the Nominative Plural affix by 7.3.108 — 7.3.109, the णित्व operation of this rule will not again take place. Or गोतः in the sutra may be construed as Sambandha-lakshana Sasthi (a Genitive denoting a general relation): and the meaning will be "that sarvanamasthana affix, denoting singular, dual, plural, which refers to the meaning of गो the or 'cow.' While in चित्रगु, the sarvanamasthana affix does not refer to 'cow' but to another object, namely to a 'person' who possesses brindled cows. त् in गोत् in this view is for specification only.

Some read the sutra as ओतः णित्, so that the rule will apply to द्यो also: as, द्यौः, द्यावौ, द्यावः ॥ If the reading be taken गोतः, then we extend this rule to द्यो also, by taking गो as merely illustrative of all words ending in ओ; and this is done by the letter त् in गोतः, for the तपर rule applies to letters, and not to words, so that गोतः means and includes गो and words ending in ओ ॥