Joint International Conference on Long-term Experiments ...

iological additives (the inoculants) have been approved by the FDA and can be used in
ensiling forages (Anon, 1997).
The research performed in this domain (Wilkins, 1996; Steen, 1997 ; Keady, 1998,
2000 ; Mierlita 2002) has shown that using inoculants for corn ensiling has led to a
significant reduction of the ammoniac level (a criterion for evaluating proteolysis), to a
greater consumption (3.8 – 5.2%) and a better digestibility of DM (1.7-4.0%), to a
greater weight gain in bulls intended for fattening (3.8-12.2%), to a better quality and
quantity of cow milk (1.7 -2.2 l/day and an increase of the protein level by 0,05%) as
well as to the improvement in the degree of food capitalization (by 6%).
In our research we have analyzed the effect of using an inoculant with mixed types
of homofermentative lactic acid bacteria with high tolerance to acidity, which would be
able to control the fermentations throughout the ensilaging period (Lactobacillus
plantarum + Pediococcus pentosaceus – 10 6 units forming colonies/g), on the
nutritional qualities of corn silage as well as on the fattening performances of bull
calves.
MATERIALS AND METHODS
The corn used in the ensiling process was harvested in an advanced state of vegetation
(kernel: wax-glass-like) with a content of 33-34% DM. Two silages were created : one
by natural fermentation and the other by using an inoculant with mixed types of
homofermentative lactic acid bacteria with high tolerance to acidity, composed of
Lactobacillus plantarum + Pediococcus pentosaceus (10 6 units forming colonies/g).The
research concerning the productive effect was performed on two lots of weaned bull
calves of the Romanian Baltata breed (12 heads / lot), aged about 3 months give or take
14 days. The fattening period lasted 426 days (14 months), respectively from the age of
3 months (after the weaning of the calves) and up to the age of 17 months. Of the two
lots, one was considered a control group (GC) and received naturally fermented corn
silage in its food, and the other was considered an experimental group (GE) and
received corn silage obtained by adding an inoculant (treated). The corn silage ensured
50% of the ration’s DM in both groups; the ration was completed by hashed alfalfa hay
(10% of DM) and a mix of concentrates (40% of DM) (table1). The food was
distributed in abundance in the form of unique forage mixtures.
Table 1: Experimental scheme
Associated activities
Objective Control lot (GC) Experimental lot
(GE)
1. The influence of
using inoculants with
mixed types of lactic
acid bacteria on the
nutritional qualities of
corn silage.
Corn ensiled by
means of natural
fermentation.
328
Corn ensiled by
adding inoculant :
Lactobacillus
plantarum +
Pediococcus
pentosaceus (10 6
units forming
colonies/g).
Surveyed aspects
- The chemical
composition of the
fermented forage
(DM, raw protein,
raw cellulose) ;
- pH ;
- ammoniacal N;
- lactic acid (g/kg
DM);