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A MANUAL OF VETERINARY PHYSIOLOGY 



are considerably increased, owing to an absorption of part of the 

 water of the bile. The secretion in the horse contains no mucin, 

 and, according to Ellenberger, there is very little mucin in the 

 bile of sheep ; what was believed to be mucin in ox bile, which 

 conferred on the latter its ropy character, is now known to be 

 nucleo-albumin. 



The dried alcoholic extract of bile contains in the ox 3-58 per 

 cent, of sulphur, sheep, 571 per cent., and pig, 0*33 per cent. 

 The gases found in bile are C0 2 , and traces of O and N. The 

 chief inorganic salts are sodium chloride and phosphate, besides 

 which are found salts of calcium, magnesium, potassium, iron, 

 with phosphoric and sulphuric acids ; the sodium salts always 

 exist in the largest proportion. The iron, which is found as 

 phosphate, is probably derived from the haemoglobin of the blood 

 during the formation of the bile pigments. 



The following table, showing the percentage composition of 

 various biles, is mainly compiled from Ellenberger : 



Percentage Composition of the Ash of Ox Bile. 



The differences found in the composition of bile probably 

 depend upon whether it be taken from the gall-bladder or from 

 a fistula, the former being the more concentrated. 



The Bile Pigments are two in number — bilirubin and biliverdin ; 

 the latter is produced by oxidation from the former. Bilirubin 

 is the colouring matter of human bile and that of carnivora, 

 whilst biliverdin is the pigment of the bile of herbivora. It is 

 not uncommon to find both pigments in the same specimen of 

 bile. Though the bile of the dog contains exclusively bilirubin 

 as a pigment, yet the placenta of this animal is rich in biliverdin. 

 In the ox and sheep a pigment is present in bile which shows 



