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of potash is ingested) the lime requirement has been found to be higher. In the
case of Napier the condition is probably further aggravated as the potash inges-
tion is considerably higher while the low lime ingestion does not provide any
margin to ensure a definite positive balance. This is typically reflected in the
behaviour of animal D 5 which probably suffered systematically from a faulty
lime assimilation which adversely reacted on phosphate balance in spite of a
high P 2 O 5 intake. It has been pointed out, as already stated under lime by Meigs
et al [1926], that a long continued loss of lime will cause a loss of phosphorus
even though the ration may contain plenty of assimilable phosphorus as is nor-
mally expected in a green feed (vide also under lime). It is very striking in this
animal (Table VII) that lime, magnesia, potash, phosphorus and nitrogen were
all negative. Only soda and chlorine were positive.
Phosphorus ingestion in experiments exhibiting deviation
It remains now to take up the results of rice kura in which as already stated,
the conditions are probably governed by other factors. The phosphorus con-
tent in the rice kura is very large (about 6 per cent in the sample used) and
naturally the ingestion in individual animals were far more than in any other
feed. This experiment would thus have served as a suitable example of exces-
sive feeding of P2O5 but due to other factors the conditions have been different.
The phosphorus in rice kura is largely in the form of phytin. Winton and Winton
[1932] cite from Suzuki, Yoshimura and Takaishi that rice bran contains about
8 per cent phytin. The same authors also report on the work of Rather [1918]
that of the total soluble phosphorus about 87 per cent and 93 per cent
were found in rice bran and rice polish, respectively, as inosite penta¬
phosphoric acid. It has been already stated that the feeding of rice
bran was followed by low appetite, loss of condition and so forth.
This is in all probability associated largely with the nature of phosphorus
compound in the feed as would appear from the work of various investigators. Thus
Bruce and Callow [1934] reported that " the apparent rachitogenic effect of cereals
when compared with other materials of the same phosphorus content is due to
the fact that cereal phosphorus is not in an available form ". They expressed
that " the differences between oat-meal, maize and white-flour can be completely
accounted for by differences in the total phosphorus content and in the propor-
tion of inositol—hexa-phosphoric acid". McChance and Widdowson [1935]
fed phytin to three adults and one child and found that 20 to 60 per cent of the
phytin was excreted unchanged in the faeces. It would appear from these investi-
gations that phytin remains largely unchanged in the case of rats, dogs, men and
cattle. In the case of pig, however, Rather [1918] found after feeding large
amount of phytin in the natural state that almost all the phosphorus was ex-
creted in the form of orthophosphoric acid and his conclusion was that pigs can
hydrolyse the phytin completely. Lowe and Steenbock [1936] also fed rats