18 Milk and Its Products 
per cent of fat is recorded from any cow giving as 
much as 15 pounds of milk per day. Any analysis 
above 7 per cent is extremely rare, and should be 
regarded with suspicion unless well authenticated. 
The mixed milk of herds seldom falls below 3 per 
cent of fat and rarely rises above 5.5 per cent. 
Colostrum.—The first milk secreted by the animal 
after parturition is quite distinct in composition and 
physical properties from that produced after the 
secretion has become well established. Such milk 
is called colostrum, and is ordinarily considered 
unfit for consumption or manufacture. Colostrum 
differs from normal milk chiefly in its less proportion 
of water and sugar, in the much greater proportion 
of albumin and ash, in the extremely variable amount 
of fat, and in the presence of small organized bodies 
known as colostrum corpuscles, which are probably 
debris of the cell structure of the gland. The follow- 
ing analyses from Richmond after Vaudin show the 
extremely variable composition of colostrum: 
: No. 1. No. 2. 
Waters els Ke Es ee a Se Se ee ee 72.39 75.51 
Fat Sige” Re RL ae ee SCS 1.30 6.32 
Sugar % -g4see8 8 FHSS Swe as 1,52 2.17 
Proteids (casein, albumin, ete.)......... 23.70 14.91 
ASH see dt te es Sa He aches A 1.09 1.09 
100.00 100.00 
The percentage of albumin in colostrum is s0 
great that it will cause the whole mass of milk to 
thicken upon boiling, and this is ordinarily consid: 
ered a sufficient test for determining the suitability 
of the milk for consumption or manufacture. With- 
