Energy value of crude glycerol in 11 and 110 kg pigs
Lammers, P., Kerr, B., Weber, T., Dozier, W., Kidd, M., Bregenhahl, K., Honeyman, M. (2007) Energy and protein metabolism and nutrition. EAAP publication No. 124, 2007, V
08-Nov-2007 (18 years 7 months ago)One of the main co-products of biodiesel production is crude glycerol which
can be available for use as an energy feedstuff for pigs. Some studies have
reported the effects of feeding glycerol to monogastric food animals but no
studies have reported the metabolizable energy content of crude glycerol when
fed to pigs. The objective of this work was to study the energy content of crude
glycerol when fed to pigs of different body weight.
Two experiments were carried out, the first being done with piglets of 11 kg
and the second with heavier pigs (110 kg). A total of 24 starter piglets of
11kg, and 24 finisher gilts were individually caged in cages that permitted
total and separate collection of feces and urine. Animals were fed one of the
four diets, basal diet (BD) or the BD with an additional 5, 10 or 20% of glycerol
(3625 kcal gross energy per kg), BD composition differed between that offered
to starter piglets and that offered to finisher gilts. After a 10 days adaptation
period, feces and urine were collected for 5 consecutive days in order to determine
energy content. Apparent metabolizable energy (ME) of the diet was calculated
as the difference between feed gross energy content and the sum of energy excreted
in feces and urine.
Response of apparent ME content of crude glycerol was quadratic (P < 0.01)
in starter piglets, being the apparent ME content of 3601, 3239 and 2579 Kcal/kg
for diets presenting 5, 10 and 20% of glycerol respectively. When not taking
into account starter piglets fed 20% of glycerol, the response was lineal and
the apparent ME content estimated for glycerol was of 3463 Kcal/kg. On the contrary,
in growing pigs crude glycerol response was lineal, providing an apparent ME
content of 3081 Kcal/kg.
Therefore, up to 10% of crude glycerol can be supplemented to weaned piglets,
obtaining an apparent ME of approximately 96% of the gross energy content of crude
glycerol, while in finishing pigs higher levels can be used with an approximately
85% of the gross energy content of crude glycerol.