How big is the pig to raise the most benefit?

Principle

In the high profit stage, the big pigs; in the low profit stage, there are three measures to improve the feed-meat ratio: (1) early out of the fence; (2) reduce the density; (3) pick and feed the pigs.

explain

In order to achieve high profits, it is incorrect to pursue a low feed-to-meat ratio or a high speed. The two should be put together, and the average daily profit of a pig should be calculated, because 365 days a year is fixed (if the pigsty is tight, raising big pigs will reduce the number of pigs, that is, a batch of piglets must be sold. This situation is related to the price of piglets: if piglets are expensive, big pigs weighing more than 180 jin are more cost-effective.

Give examples to illustrate

A little pig, eat a jin of material to grow a jin of meat, a day to grow a jin; a big pig, eat 2 jin of material to grow a jin of meat, a day to grow two jin. The price of feed is 1.5.

If the price of pig is 7.5 yuan / jin, the average daily profit of big pig is 9 yuan (7.5-2-2-1.5), the average daily profit of piglet is 6 yuan (7.5-1.5), and the daily profit of big pig is high.

If the price of pigs is 4 yuan / jin, the average daily profit of big pigs is 2 yuan (4-2-2-1.5), that of piglets is 2.5 yuan (4-1.5), and that of piglets is high.

The above is a qualitative analysis, in the end how to decide whether to fence a big pig or a small pig according to the pig price and feed price?

The formula for calculating the average daily profit is as follows

Average daily profit = average daily gain * pig price-average daily gain * feed / meat ratio * feed price = daily gain * (pig price-feed / meat ratio * feed price)

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Stage jin

Average daily weight gain

Feed to meat ratio

Total food

Number of days

30 murals 60

30/28

51.1/30

51.1

twenty-eight

60 Mustang 180

120/76

324.1/120

324.1

seventy-six

180-200

20/10

57/20

fifty-seven

ten

60 murals 200

140/86

381.1/140

381.1

eighty-six

30-200

170/114

432.2/170

432.2

one hundred and fourteen

200 Mustang 220

20/9

62/20

55.8 (62)

nine

It is necessary for ① to raise 60 kg of pigs and 180 jin of pigs, and we mainly look at whether the stage after 180 jin is worth raising.

Average daily profit (60ml 180jin) = average daily weight gain 1 * (pig price 1-feed meat ratio 1 * feed price) (the relevant data mark of 60fu 180jin stage is 1, and that of big pig stage is 2)

Average daily profit (after 180 jin) = average daily weight gain 2 * (pig price 2-feed meat ratio 2 * feed price)

If the big pig is worth raising, the average daily profit (after 180 jin) > the average daily profit (60 kg). The deduction is as follows:

(average daily gain * pig price 2-average daily weight gain * pig price 1) / feed price > (average daily gain * meat ratio 2-daily gain * meat ratio 1)

Replace the data of each stage into the calculation, if the above formula is established, the average daily profit will be high after 180 jin, and the column will be released late, otherwise, it should be listed early.

② if the price of big pig and small pig is the same, the above formula is changed to:

(pig price / feed price) > [(average daily gain * daily gain ratio 2-daily gain ratio 1)-(average daily gain 2-daily gain 1)]

Raising pigs or selling piglets?

The cost of pigs includes 30 jin of piglets and 30 jin of feed up to the time of fencing. Take 200 jin as an example, the price below 30 jin is the price of pig (less than 30 jin).

The total cost is: 30 * pig price (less than 30 jin) + feed price * 170 * feed / meat ratio (30 to 100)

The break-even price of pigs is: total cost divided by 200.

If the profit is not high, it should be listed early, otherwise, it should be late.