I think it will be better to post here how I formulate my feeds. It reminds me what my buyer of hogs told me that "under present condition, high cost of feeds and low price of liveweight, only those raisers that formulate his basic feed mix will survive".

For the duck nutritional requirement as per book available, it require 16% crude protein (CP) and 2900 k/cal metabolized energy (ME). Using the basic feed mix posted earlier as an example, presented below is my calculation:

CP % ME k/cal

Rice bran D2 8 2365

Broken rice (binlid) 7.8 2990

Snail-meat (est. 30%) 50 2155

Source: A Primer on Pork Production by Valentino G. Arganosa, UPLB

There is no specific laboratory chemical analysis of snail's meat and I will use for the meantime the local fish meal data to complete my calculation. Also, I only use 30% as temporary figure for the snail's meat weight for kl of snail, the rest (70%) is shell's weight.

The calculation of CP % for basic feed mix will be as follows:

Rice bran, D2 50 kg (50 x 8%)/100= 0.04

Broken rice 20 kg (20 x 7.8%)/100 = 0.015

Snail's meat (30%x25kg) 7.5 (7.5x 50%)/100 = 0.0375

shell 17.5 0

Minerals/etc. 5 0

Total 100 0.09.2 or 9%

For ME my calculation is as follows:

Rice bran, D2 50 kg (50 x 2365)/100 = 1182

Broken rice3 20 (20 x 2990)/100 = 598

Snail's meat 7.5 (7.5 x 2155)/100 = 161

shell 17.5 0

Minerals/etc. 5 0

Total 100 1941

Based on the above estimated calculation CP is short by 7% (16-9) and ME by 959 (2900-1941).

In order to get a 16% CP, I will use copra meal and fish meal as a source of protein;

Copra has 21% CP and 3000 k/cal ME and for fish meal, it is shown above:

Rice bran, D2 20 kg (20 x 7.8%)/100 = 0.0156

Broken rice 20 (20 x 7.8%)/100 = 0.015

Copral meal 30 (30 x 21%)/100 = 0.063

Fish meal 5 (5 x 50%)/100 = 0 025

Snail's meat 7.5 (7.5x50%)/100) = 0.0375

shell 12.5 0

Minerals 5 0

Total 100 01561 or 15.6%

By adding 30 kg copra meal and 5 kg fish meal and reducing rice bran by 35 kg in the mix, I was able to attain 15.6% CP which is close enough to duck's nutritional requirement of 16%.

For the ME, the mix will give result to as follows:

Rice bran, D2 20 kg (20 x 2365)/100 = 473

Broken rice 20 (20 x 2990)/100 = 598

Copra meal 30 (30 x 3000)/100 = 900

Fish meal 5 (5 x 2155)/100 = 107

Snail - meat 7.5 (7.5 x 2155)/100 = 162

shell 12.5 0

Minerals 5 0

Total 100 2240

It is still short (2900-2240) by 660 k/cal. I will use vegetable oil that has 7975 k/cal to attain 2900. By adding 8 kg of vegetable fat it will give an additional k/cal of 638 (8 x 7975)/100= 638 k/cal. It (2240 +638= 2878) will be close to the requirement of 2900 k/cal.

With the use of an Excel spreadsheet, it will be easy to calculate other parameter to have a balance feed mix.