Prabhupada's lecture - Śrīmad-Bhāgavatam 1.10.4 - London, November 25, 1973
This is the description during the reign of Mahārāja Yudhiṣṭhira. Mahārāja Yudhiṣṭhira was the king of this earth, and he was so pious that on account of his piety, Kṛṣṇa supplied everything sumptuously, sumptuously. Now, have you ever experienced...? Now, here it is stated, siṣicuḥ sma vrajān gāvaḥ [SB 1.10.4]. Now, we are hankering after milk, but in those days, during Mahārāja Yudhiṣṭhira's time, milk was so sufficiently produced that before milking the cow, it supplied milk so sufficiently that the... What is called? Grazing ground? Pasturing ground, they become muddy. They become muddy with milk. Now, with the scarcity of grain, the earth also does not become muddy. It becomes dry earth. But in those days, with milk it was muddy. Just imagine how much milk was... And how it is possible? Siṣicuḥ sma vrajān gāvaḥ payasodhasvatīr mudā [SB 1.10.4]. The milk bag was so fatty and full with milk. Why? mudā, they were so happy.
They were so happy. So if you keep the cows happy, then cow will supply large quantity of milk. If the cow knows that you are going to kill it, she is always afraid, always fearful: "Oh, this man will kill." They can understand. I have seen in New Vrindaban. One cow, she was crying because her calf was taken away. So she was feeling so sorry. Now in our New Vrindaban, we see how the cows are happy, how they are dealing. They are not afraid. This is our duty, to keep the cows happy. Just like I want to see my wife and children happy, similarly, it is the duty of the human society to see that the cows feeling very happy. This is human civilization. Otherwise it is tiger civilization, meat-eaters. Meat is not eaten by human being. It is eaten by the dogs, by the tigers, by the animals.