Energy value of ensiled lucerne and red clover leaves and their impacts on performance in pigs

Summary in the original language of the document

Silages from the leaf fractions of lucerne and red clover may be a valuable energy source for swine. The aim of this
study was to measure the energy value of ensiled lucerne (LLS) and red clover leaves (RLS) (trial 1) and the effects
of two levels of dietary inclusion (10 and 20%) of LLS and RLS on growth performance (trial 2). In trial 1, total tract
digestibility coefficient (TTDC) of energy was measured on a total of 15 pigs (68 kg BW) allotted to 3 different dietary
treatments in which silages were given as an additional ingredient with control diet (C), C+22% of LLS (LLS diet),
and C+22% of RLS (RLS diet). In LLS and RLS diets,. In trial 2, a total of 60 growing-finishing pigs (97.0 kg on
average at the beginning of the 17-d trial) were divided into 5 experimental treatments planned to supply the amount of
metabolisable energy (ME, i.e. 37.4 MJ/d) for a fixed amount of DM allowance (i.e. 2.6 kg/d). Pigs from the treatment
1 (T1) were fed a R1 diet formulated from cereals (corn, barley, wheat), wheat bran and soybean meal (12.5 MJ ME/
kg and 0.45 g SID lysine/MJ ME). Pigs from T2 and T3 were fed with a mixture of 90% of a R2 diet and 10% of LLS
or RLS. Pigs from T4 and T5 received a mixture of 80% of a R3 diet and 20% of LLS or RLS. For compensating the
lower ME and protein contents in silages, wheat bran was partially or completely substituted by cereals and soybean
meal in R2 and R3 diets, respectively. In the LLS and RLS diets, TTDC of energy was significantly (P<0.05) than
in the C diet. On average, DE values of LLS and RLS were respectively 14.0 and 13.8 MJ/kg DM. From the trial 2,
ADG and FCR were significantly (P<0.05) influenced by the dietary treatment with depressed performance for the
T4 group when compared to the others treatments (796 vs 889 g/d; 3.23 vs 2.90 kg/kg). In conclusion, our results
suggest that lucerne and red clover leaf silages have a potential as energy sources in finishing pigs but further studies
are needed to better understand why growth performance are reduced in pigs fed 20% Lucerne silage.