In trial Ithree lactating Polish Holstein-Friesian cows fitted with rumen cannulae
and selected upon their daily milk yield (28±3 kg) and body live weight (603±5 kg)
were used. The trial was conducted according to the 3 ×3 Latin square design. Each
of three experimental cycles lasted 24 days, including 21-days preliminary period
and three days of sampling. The control diet was composed of fresh alfalfa, maize
silage and commercially available B-type concentrate supplemented with wheat bran,
barley germs and maize meal. The diet was balanced and formulated according to
INRA standards to contain 1735 PDIN, 1639 PDIE and 16.47 UFL [IZ-INRA 1993].
Programme INWAR version 1.0 and INRAtion version 2.63 of 1998 were used for
calculation