According to Swami Dayanand (1824-1883) and his book- ‘Go- Karuna Nidhi’, one cow can feed or support 410,440 people at least once during her lifetime along with her offsprings whereas if slaughtered one cow’s meat can feed only 80 people. His Calculations are as follows:
The milk from a cow can range between 2 Litres to 20Litres(L) per/day. Therefore the Average. milk per cow is expected to be approximately 11Litre per/day. In one month, therefore, the amount of milk will be 11L x30 days or 330 Litres per cow on average.
The milking period of cows ranges between 6 months-18 months therefore the Average. The milking period will be 12 months. Hence. Avg. milk per year will be 330Lx12months or 3960L per cow.
Making rice pudding (i.e. Kheer) from 3960L will feed 1980 people if each eats Avg. 2L equivalent milk’s rice pudding.
A cow gets pregnant 8-18 times during her lifetime, Avg. 13 times per cow. The total number of people that can feed on one cow’s lifetime milk is 1980 x13 or 25,740 people eating once each.
We discussed that an Average cow will get pregnant approximately 13 times in her lifetime. We presume that this will result in 6 female cows and 7 male cows. Presuming that one male cow will die during pregnancy also, we are left with 6 female cows and 6 male cows.
As seen above 25,740 people can be fed from one cow lifetime milk, therefore the 6 female cows, produced by one cow during her lifetime will feed in total 25,740 x 6 or 154,440 people during their combined lifetimes. So, ‘A’ (that is contribution from Female cows) = feeding 154,440 people at least once.
Now, consider the contribution of the 6 male cows also produced by the same cow. 6 male cows or 3 pairs of them can plough fields to produce crops. Each pair can help to produce 8000 kg of food grain/year. So, 3 pairs can help in the production of 24000 kgs of grain per year.
The average working life of a male cow is 8 years approximately so 3 pairs can produce 24000kg x 8 years or 192,000 kg total in a span of 8 years. On average, one can consume no more than 750gms of food grain each time. Therefore, the number of people that can be fed by the work of 6 male cows will be 192,000kg divided by 0.750gms or 256,000 people eating at least once. We call this result as ‘B’= 256,000 people
Adding A+B gives us the following,
A = Female cows contribution……. 154,440 people
B = Male cows contribution ………… 256,000 people
A+B = 410,440 people
To sum up, we can conclude that One cow and its offspring can feed or help feed 410,440 people at least once.
The meat of one cow can feed only 80 people, therefore it makes no sense to kill a cow for meat consumption.