S. Kracmar et al., CHANGES IN AMINO-ACID-COMPOSITION OF GOATS MILK DURING THE FIRST MONTH OF LACTATION, Czech Journal of Animal Science, 43(6), 1998, pp. 251-255
In goats of the White Short-wooled breed of the 2nd and higher lactati
ons, changes in amino acid composition of milk were studied from the 5
th to the 33rd days of lactation. The amino acids serine, proline, gly
cine, alanine, glutamic acid, aspartic acid, arginine, histidine, meth
ionine and cystine indicated a gradual and even decline during the per
iod under study; in lysine and valine by the 19th day, a moderate decl
ine tendency was registered, followed by a sharp drop by the 26th day.
In threonine and isoleucine, a sharper drop was registered by the 19t
h day of lactation, and in phenylalanine, a very sharp drop occurred b
y the 26th day of lactation. From the 26th day of lactation, a gradual
decline was registered in all amino acids. During that period, in non
-essential amino acids (NEAA), the decline ranged 0.39-10.05%; in esse
ntial amino acids (EAA), it ranged 0.79-41.54%. Within the sum of NEAA
and the sum of Met + Cys, the decline was gradual and regular. Within
the sum of EAA, during the period from the 5th to the 26th days of la
ctation, a sharper drop followed by subsequent gradual decline was evi
dent.