170
The Chemical Composition of Colostrum Butterfat
The carotene content of butterfat is known to change with the type of feed, but in the present
experiment the feed was the same throughout for all animals. Here too, there is a good deal of in-
dividual variation and the concentration decreases rapidly till the fifth day. No marked variation
is noticeable in the concentration of carotene between the first day's colostral fat of heifers and
cows. Breed variations were also not appreciable, but these results cannot be taken as conclusive
as only few animals were tested. The relative importance of colostrum in providing the young of
the species with a reserve of vitamin-A is quite evident from the high concentration of this vitamin
and its precursor found in colostrum.
SUMMARY
1. The changes in the physical and chemical composition of the colostral butte
from 7 cows
were tested. In general the R.M., Polenske value and saponification number tend
ise as days
advance whereas the iodine value and refractometer reading fall gradually.
2. The colour of the colostral butterfat especially in the first two days after parturition was
deep orange.
3. Colostral fat was about five to six. times richer in carotene and vitamin-A than normal
butterfat.
4. Both carotene and vitamin-A decreased rapidly during the first five days, after which the
decrease was relatively slow.
5. The amount of vitamin-A in the colostral fat from heifers appeared to be higher than that
in the colostral fat of cows.
REFERENCES
Banerjee (1936). Agric. and Livestock in India 6, 274
Dann (1933). Biochem. J. 27, 1998
Drummond, Coward and Watson (1921). Ibid. 14, 540
Engel, Schlag and Mohr, Milchwirtschaft crsh. 2, 47
Gillam, Heibron, Ferguson and Watson (1936). Biochem. J. 30, 1728
Henry, Houston and Kon (1940). J. Dairy Res., 11, 1.
Kunnerth, Kramer, and Riddell (1935). Trans. Kansas Acad. Sci. 38, 209
Kurochkin (1927). Jaroslav. Zoo-technical Exptl. Sta. Work for 1926, 142
Kramer, Bair, Kunerth and Riddell, J. agri. Res. 56, 227
Semb, Baumann and Steenbock (1934). J. Biol. Chem. 107, 697
Stewart and McCollum (1938). J. agri. Sci. 28, 428
Shah (1936). Indian J. vet. Sci. 6, 234
Sivasubramanyan and Dover (1938). Ibid. 8, 29
Tcheteheroff (1931). Mat. Gras., 23, 9198
VARIATIONS IN THE CHEMICAL CONSTANTS OF THE BUTTERFAT OF
FOUR BREEDS OF INDIAN CATTLE
By I. P. SINGH, T. M. PAUL, C. P. ANANTAKRISHNAN and M. C. RANGASWAMY, Imperial Dairy
Research Institute, Bangalore
(Received for publication on 5 November 1945)
V ARIOUS factors cause variation in the composition of butterfats [ Hagland et al., 1930 ; Kilde
and Winther, 1930; Mpolomovsky and Thomas, 1933; Maynard et al, 1936; Groh, 1937]. The
effect of feed is an established fact—but not much data is available regarding the effect of the stage
of lactation, season of the year etc., on the composition of the butterfat. Moghul et al [1945] have
studied the effect of supplementing the normal ration with various oils on the yield and chemical
composition of butterfat of the different breeds of Indian cattle and reported a lowering of the R. M.
value and an increase of the iodine value and B. R. reading. Singh et al [1945] have reported that
a supplementary feed of hydrogenated groundnut oil lowered the R. M. and Polenske values and
increased the iodine value and B. R. reading whereas hydrogenated coconut oil lowered all the three