Joint International Conference on Long-term Experiments ...

THE INFLUENCE OF USING BIOLOGICAL ADDITIVES ON THE
NUTRITIONAL QUALITIES OF CORN SILAGE AND ON THE FATTENING
PERFORMANCES OF BULL CALVES
Daniel Mierlita; I. Chereji; Cristina Maerescu
University of Oradea, Romania, 26, Magheru Street, Oradea;
ABSTRACT
Ensiling corn by using a biological additive based on homofermentative lactic acid
bacteria (Lactobacillus plantarum + Pediococcus pentosaceus) ensures, by comparison
with natural fermentation, a forage with higher nutritional qualities, with a lower pH
(acid), a lower content of ammoniacal N and raw cellulose and more undegraded
protein. The use of corn silage treated with inoculant in the food of young bull calves
intended for fattening, has ensured a significant growth in weight gain, DM
consumption and degree of the food’s capitalization, as opposed to the lot which
received naturally fermented forage in the rations. Thus by using inoculant to ensile
corn, the period of fattening was decreased by 26 days and 82 kg of concentrates and
120 kg of corn silage were saved. The biological additive used for the ensiling has not
influenced the output of slaughtering, but it has led to the increase of the muscle area,
which is positively correlated with the proportion of superior quality meat in the
carcass.
Keywords: corn silage, inoculants, fattening up bull calves.
INTRODUCTION
For fattening up young bulls, using fermented forage (especially corn) represents the
most efficient form of feeding, taken into account the technical and economical
advantages that it provides (Halga, 2005). The process of ensiling the forage depends on
the dominance of the lactic acid bacteria over the rest of the microflora, which, in
anaerobic conditions, increase the acidity of the environment, thus reducing the
competition between microorganisms. The efficiency of the ensiling process is given by
the way in which sugars are fermented in acid and by how the altering processes
determined by the clostridium bacteria (butyric acid bacteria) are avoided (Woolford-
2004). It is important that the decrease of pH in the ensiled forage be done as quickly as
possible (during the first 2-3 days) in order to avoid the degradation and loss of the
protein (Webb, 1998). During the uncontrolled processes of fermenting the silage, 45%
of the protein is decomposed up to NH3N (Jones, 1995; 1996).
The control of the silage’s fermenting was accomplished by using inorganic acids
for a long time (sulfuric, phosphoric and hydrochloric acids) or external organic acids
(formic and propionic), which had a series of negative effects in the short run (ruminal
and metabolic acidoses, ruminal parakeratosis) but especially in the long run,
materialized usually in the reduction of fertility as an effect of the acids collecting the
microelements (Suttle, 1998). At the present time, because of modern biotechnologies,
the guiding of silage fermentation is performed by using biological additives that
contain selected strains of lactic acid bacteria, especially lactobacillus, or lactic acid
bacteria and enzymes (cellulase, hemicellulase, amylase). In the USA only the
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