This study determined the effect of total mixed fi ber (TMF) from agro-industrial by-products as
a roughage source for lactating dairy cows on digestibility, milk yield and milk composition. A completely
randomized design was employed on fi fteen 87.5% Holstein Friesian crossbreds in mid lactation. All
cows had an average initial body weight of 416.03±34.66 kg and 115.20±20.32 days in milk. Cows
were randomly allocated to three treatments (T1 = cows fed pineapple peel silage with rice straw (PS)
ad lib; T2 = cows fed TMF ad lib; T3 = cows fed TMF ad lib and 1 kg less of concentrate (TMF-1). All
cows were fed with 20.35% crude protein (CP) of commercial concentrate feed. The results revealed
that the total dry matter intake of the PS group was higher than those of cows fed with TMF and TMF-1,
respectively (P < 0.05). The apparent digestibility of dry matter (DM), organic matter, crude protein,
neutral detergent fi ber and acid detergent fi ber in cows fed PS was lower (P < 0.05) than with TMF.
Estimated energy intake of diet with PS (1.71 ± 0.15 Mcal per kilogram DM) was lower (P < 0.05) than
energy fed with TMF (2.34±0.13 Mcal per kilogram DM) and TMF-1 (2.26±0.25 Mcal per kilogram
DM). The milk yields of cows fed TMF and TMF-1 (14.55±1.95 and 14.32±1.76 kg.d-1) were higher
than cows fed PS (P < 0.05). However, the milk composition was not signifi cantly different (P > 0.05)
in all treatment groups.