ABSTRACT:The first part of the study concerns the effect of the stage of maturity on nutrient content and leaf percentage of lucerne (Medicago sativa). The plants of lucerne were harvested and analysed at several stages of growth. The crop yield and changes in the concentration of nutrients were determined. The leaf percentage from whole herbage and leaf yield were determined as well. The leaf percentage at the growth stage of small buds was significantly (P < 0.05) higher than at the growth stage of bloom in all three cuts (1 st cut 52.7% vs. 46.62%; 2 nd cut 52.03% vs. 44.70%; 3 rd cut 50.58% vs. 46.26%). Crude protein content of lucerne was decreased significantly (P < 0.05) from the large bud growth stage (small buds 219.6 g/kg DM and large buds 203.1 g/kg DM vs. bloom 173.5 and after bloom 154.2). In the second part of the study, the effect of silage additives on fermentation characteristics of lucerne was investigated. The bacterial inoculant (containing homo-and heterofermentative lactic acid bacteria), chemical additive (containing formic acid, propionic acid, ammonium formate and benzoic acid) and the bacterial inoculant with benzoic acid were used for the improvement of fermentation process.The addition of the inoculant with L. buchneri increased acetic acid (P < 0.05) concentration compared to the silage with chemical additive (group I with inoculant -1.22%; group Ch with chemical additive -0.84%; group ICh with chemical additive and inoculant -1.43). Control silage (C) without additive contained 1.14% acetic acid in dry matter.Keywords: lucerne; leaves; stems; buds; bloom; nutrients 331Czech J. Anim. Sci., 53, 2008 (8): 330-335 Original Paper (McDonald et al., 1987).The aim of this study was (i) to assess the effect of harvest date on the yield and quality of lucerne, and (ii) to compare the effects of additives on quality parameters of lucerne silage. MATERIAL AND METHODSThe effect of harvest date on the yield and quality of lucerne herbage was determined in the first experiment (2004). The objective of this experiment was to examine changes in leaf and stem characteristics of lucerne herbage. These data were determined at the growth stage of small buds and bloom during the first, the second and the third cut.Lucerne, cultivar Europe, was grown in an experimental field of the Research Institute of Animal Science (280 m above sea level) near Prague. The average temperature in this area during the last six years was 9.7°C and average total precipitation was 601.3 mm. Lucerne was planted at the seeding rate of 18 kg/ha with wheat as a foregoing crop and legume-cereal mixture as a cover crop. The area 15 × 15 m was marked out at each cut in the 10 ha lucerne field and six samples (each 1 × 1 m) were chosen for cutting at the growth stage of small buds and six samples at growth stages of large buds, bloom and after bloom. Six samples (each 1 × 1 m) were cut at two growth stages (small buds and bloom). The remaining part of the 10 ha field was cut at stages of maturity when the 30% growth had large bud...

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Tyrolová Y., Bartoň L., Loučka R. (2017): Effects of biological and chemical additives on fermentation progress in maize silage. Czech J. Anim. Sci., 62, 306-312.The objective of this study was to evaluate the effects of bacterial and chemical additives on the number of lactic acid bacteria (LAB) and on fermentation indicators in whole maize silage at 1, 3, 5, 10, and 90 days of fermentation. Maize forage was harvested at approximately 34% dry matter (DM) and treated with (1) no additive (control; C); (2) bacterial inoculant (2 g/t of forage; B) containing the homofermentative LAB Lactobacillus plantarum, Lactobacillus paracasei, and Pediococcus pentosaceus (1.5 × 10 11 cfu/g of inoculant); and (3) chemical additive (4 l/t of forage; CH) containing formic acid, propionic acid, ammonium formate, and benzoic acid. Both treatments decreased pH of silage at day 1 of ensiling (P < 0.05), and the lowest value of 4.34 was observed in the CH-treated silage. All silages were well fermented and had pH < 4.0 by day 10 of fermentation. The concentration of lactic acid and the lactic acid : acetic acid ratio increased over time in all treatment groups, and the highest values were 87.5 and 3.62 g/kg of DM, respectively, observed for group B at day 90 (P < 0.05). The concentrations of water-soluble carbohydrates were higher (P < 0.05) for CH compared to C and B at days 3, 5, 10, and 90 of fermentation. The CH silage had fewer LAB (P < 0.05) than did either C or B silages regardless of the days of fermentation. Both additives used in the present study improved fermentation dynamics of the whole crop maize silage.

This study aimed to evaluate the methane-reducing potential of individual and combined treatments of low levels of nitrate (NIT) and a mixture of capric/lauric acid (CL) in dairy cows. Both in vitro and in vivo experiments were conducted. In the in vitro experiment, the anti-methanogenic effects of NIT (1.825 mmol/l) and CL (250 mg/l; capric acid, 125 mg/l + lauric acid, 125 mg/l) were evaluated in a 2 × 2 factorial design using consecutive batch incubations with rumen fluid. The NIT and CL reduced (P<0.05) methane production by 9.2% and by 21.3%, respectively. However, combining NIT with CL did not show (P>0.05) any benefit in methane reduction compared to the use of CL alone. In in vivo experiment, eight multiparous dry Holstein cows were fed two diets in a crossover design for two 21-day periods (14 days of adaptation and 7 days of sampling). The treatments were: 1) silage-based basal diet + 100 g stearic acid per cow/d (CON) and 2) silage-based basal diet + 50 g capric acid + 50 g lauric acid per cow/d (CL). Gas emissions were measured using open-circuit respiration chambers. Methane production (g/d) was reduced (by 11.5%; P = 0.012) when the diet was supplemented with CL. However, supplementation with CL increased ruminal ammonia-N concentration (by 28.5%; P = 0.015) and gas ammonia production (g/d; by 37.2%; P = 0.005). Ruminal pH, protozoa count, and total and individual volatile fatty acid concentrations (VFA) did not differ (P>0.05) between the treatments. Treatment did not affect the intake and total tract apparent digestibility (P>0.05). In conclusion, our results suggest that low CL levels have anti-methanogenic potential. However, low levels of CL may compromise nitrogen use efficiency.

ABSTRACT:The objectives of the study were to evaluate the effects of wilting and additives on the fermentation quality of field pea silage, and to determine the rumen degradability of organic matter of pea silage. The following additives were used: commercial bacterial inoculant (1 g/t) containing homofermentative lactic acid bacteria -Lactobacillus rhamnosus (NCIMB 30121) and Enterococcus faecium (NCIMB 30122) and chemical additive containing formic acid, propionic acid, ammonium formate and benzoic acid (4 l/t). Compared to the control and chemical additive, the addition of the inoculant to wilted silage increased the lactic acid content (P < 0.05) and lactic:acetic ratio (P < 0.001). Both bacterial and chemical additives decreased (P < 0.001) the pH value of wilted silage. Differences between the control and chemically treated unwilted silage were also significant (P < 0.01). The pH value of silage with chemical additive was lower compared to the control. Proteolysis determined in wilted silage was lower compared to unwilted silage. Rumen degradability of organic matter in wilted silage treated with the chemical additive was found to be higher (P < 0.05) than in control and inoculant treated silages.