[5] ARTIFICIAL FEEDING OF CARP. 1013 



ble albumen, and 0.112 kilograms of digestible hydrate of carbon pro- 

 duce 1 kilogram of albumen or 1.428 kilograms fisli-flesh ; later observa- 

 tions, however, have shown that even a smaller quantity is suflicient to 

 produce this result. 



Thus, experiments in feeding, made on a large scale on the estate 

 of Plan, in Bohemia, and described in the above-mentioned Ostei- 

 reicJiisch- Unoarische Fischerei-Zeitung, 1880, No. 32, and 1881, No. 19, and 

 carefully reviewed by me in the same journal, 1881, Nos. 23-30, showed 

 that, in order to produce 1 kilogram of carp flesh, there were required 

 0.49G kilograms of albumen, which quantity is contained in 0.664 kilo- 

 grams of meat flour; in other words, 1 kilogram of albumen produced, 

 in round figures, 2.200 kilograms of carp flesh, and 1 kilogram meat 

 flour produced 1.540 kilograms of carp flesh. 



In making these experiments there were fed in a pond of 2.41 hectares 

 1,150 young fish, and in another pond of 4.56 hectares 2,240 young fish, 

 averaging 30 grams apiece in weight. The food consisted of a mixture 

 of meat flour, blood, malt, and flour. Nothing is said respecting the 

 quantities of the different ingredients; all that we could learn was, 

 that 4 kilograms albumen had been fed per 1,000 kilograms of living 

 weight, and that the proportion of nutritive substances had been 

 Nh : Nfr=l : 1.95, and also that in this mixture the kilogram proteine 

 had cost from 84 to 88 pfennig [about 19 or 20 centsj. 



These experiments, therefore, were only made respecting the quantity 

 of albumen, on the basis of my standard of food, whilst the proportion 

 of the nutritive substances was four times greater than the one pre- 

 scribed by my standard, thus involving a very considerable waste of 

 hydrates of carbon. But as the proportion of nutritive substances 

 is increased, the amount of albumen remaining the same, the quantity 

 of flesh produced will be smaller, and the above favorable result, ob- 

 tained in spite of an increased proportion of the nutritive substances, 

 only goes to show that, if this proportion had been smaller and more 

 like the one prescribed by my rule, the fish-flesh produced would have 

 been still greater. 



My criticisms of these experiments were violently assailed by the 

 superintendent of the Plan ponds, but they could not be effectually met 

 by him, as he,leaving the subject i)roper, attacked the rule of feeding 

 itself. In doing this, however, he did not venture to assail the scientific 

 basis on which this standard rests, and consequently it could not be 

 shaken. I have therefore left the article in question unanswered, and 

 have quietly waited to see whether other pisciculturists would express 

 their approval of the views contained in said article, to do which they 

 were directly asked in the article itself. But so far no such approval 

 has been given by any one, which, 1 thinlc, sufficiently refutes the attack 

 on my standard. 



In that attack the following were the most serious objections presented: 

 (I) that the quantity of food was too small; (II) that the required pro- 



