Valmiki Ramayana Ayodhya Kanda Sarga 61 Shloka 14
Original Shlokaब्राह्मणेष्वपि तृप्तेषु पश्चाद्भोक्तुं द्विजर्षभाः। नाभ्युपैतुमलं प्राज्ञा श्शृङ्गच्छेदमिवर्षभाः।।2.61.14।।
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तृप्तेषु contented, ब्राह्मणेष्वपि even if they are brahmins, प्राज्ञाः the wise, द्विजर्षभाः bulls (best) among brahmins, ऋषभाः like bulls, श्रुङ्गच्छेदमिव shorn of their horns, पश्चात् afterwards, भोक्तुम् to partake, अभ्युपैतुम् to accept, नालम् should not.
The bulls (best) among the wise brahmins would not like to accept the food after it is tasted by other brahmins, just as bulls dislike their horns being shorn.