The quality and nutritive value of locally produced silage and hay for horses were investigated. The forage comprised a mixture of grass crops. A total of 14 silage and 14 hay samples was collected from riding stables (housing 267 horses) and analysed from 2010-2011. Silage contained an average of 8.1 MJ kg DM-1 and hay 7.2 MJ kg DM-1 of metabolizable energy, and 56 g kg DM-1 and 22.5 g kg DM-1 digestible protein, respectively. The content of mycotoxins in silage was lower than in hay. The average zearalenon content of silage was 79.1 ppb whilst that of hay was 164.2 ppb. The deoxinivalenol content was 48.2 ppb in silage and 89.5 ppb in hay.

The study investigated effects of five different microbial inoculants on silage fermentation and nutritive value. Silage was prepared from red clover-rich material with dry matter content after 24 hours of wilting of 170 g kg I 1 for the first cut and 430 g kg I 1 for the second cut. Tests with five different commercial inoculants were based on different strains of Lactobacillus plantarum which were used alone or in combinations with other lactic acid bacteria (1/BO, 2/BI, 3/SI, 4/EC, 5/BM), and chemical additive (CHEM) were used. Six commercial additives were compared with the untreated control. The additives were applied to fresh forage at the levels recommended by the manufacturers. Chemical compositions of the first and second cut of red clover were significantly different I crude protein 176 g kg I 1 and 143 g kg I 1 ; NDF 366 g kg I 1 and 503 g kg I 1 DM respectively. In the first trial, silages treated with 2/BI had lower levels of acetic acid 25.5 g kg I 1 and ethanol 8.0 g kg I 1 compared to the control values of 35.6 g kg I 1 and 11.6 g kg I 1 (P<0.05). Otherwise, the pH, and contents of ammonia nitrogen, ethanol and organic acids were no different from the control silage. In the second trial, silage treated with 1/BO and 4/EC showed the highest contents of lactic acid. Compared to the untreated control silage, the acetic acid content was lower in silages treated with 2/BI, 3/SI and 5/BM (P<0.05). The lactic acid:acetic acid ratio was higher in inoculated silages: for 1/BO, 2/BI; 3/SI, 4/EC and 5/BM it was 2.73; 2.17; 1.98; 2.03 and 2.87, respectively. The same ratio for the control silage was 1.83. All commercial inoculants improved the fermentation quality of red clover silage under the conditions stated. No differences were found between dry matter in vitro digestibility of the inoculated and the control silage for both the first and second cut. Digestibility of the red clover silage treated with CHEM was higher than that of the control silage by 4.6% for the first cut and by 7.3% for the second cut (P<0.001).

SummaryThe potential of different laboratory methods to predict legume silage organic matter digestibility (OMD) in vivo was evaluated by using data from thirty‐three pure legume silages in seven experiments. The samples were analysed for crude protein concentration, cell wall composition, in vitro digestibility by the methods of Tilley and Terry [Journal of the British Grassland Society, 18 (1963), 104–111; OMDT&T], pepsin‐cellulase solubility (OMS) and gas production (OMDGAS), and for indigestible neutral‐detergent fibre concentration in situ (INDF). The relationships between the results obtained by the laboratory methods and in vivo OMD, all expressed as ratios, were studied using linear univariate regression models with experiment as a random variable (mixed model). Legume silage digestibility could be estimated with acceptable accuracy by different in vitro methods, but not from the chemical composition of the samples. The highest accuracy in OMD prediction was found with OMS (RMSE 0·0113; R2 = 0·965) followed by OMDGAS (RMSE 0·0149; R2 = 0·944), OMDT& T (RMSE 0·0149; R2 = 0·940) and INDF (RMSE 0·0168; R2 = 0·925). The relationships between the in vitro methods and in vivo digestibility are not universal, and should be determined separately for each laboratory and type of forage. Part of the error in OMD prediction can be attributed to errors in in vivo OMD determination.

Olt, A., Rinne, M., Nousiainen, J., Tuori, M., Paul, C., Fraser, M. D., Huhtanen, P. (2005). Estimation of legume silage digestibility with various laboratory methods. In: Park, R.S.; Stronge, M.D. (eds). Silage production and utilisation. Micro-satellite of International Grassland Congress - incorporating the XIV International Silage Conference, Belfast 306 July 2005. Wageningen Academic Publishers, ISBN:9076998752, p. 267.

Legumes are widely used ensiling material as they are rich in protein. Ensiling of legumes arises several problems due to their low content of sugars, high buffering capacity and high moisture content. Attention should be paid to silage protein degradability. Objective of the study was to explain the effect of additives and wilting on the fermentation quality and nutritive value of red clover-timothy silage, protein degradability and content of amines included. Test silages from fresh material, either unwilted or wilted for 24 hours, were conserved into 3-litre jars and opened for analysis in 90 days. Biological (L. plantarum +L. fermentum) and chemical (AIV 2000) additives were used for treatment. Silage protein degradability was studied by using in sacco method with ruminally fistulated cows. As the buffering capacity of red clover-timothy mixture (50:50) is low (27.5), increasing up to 39.6 at wilting, treatment with additive is necessary to improve fermentation. The use of biological or chemical additives decreased silage dry matter losses by 1.9 to 3.7 times, significantly improving the quality of fermentation – content of butyric acid was 47 g/kg DM for test silage and 1–2 g/kg DM or 0 for silage without additive. In vitro organic matter digestibility for the silage with chemical additive increased by 4%, compared to that for the test silage (P<0.0001). Ruminal degradability of silage nitrogen was approximately 90%. Protein solubility and ruminal degradability were lower for silage with chemical additive. Ruminal degradability of silage protein after 8 h was 77.2% for the test silage, 76% for the silage with biological additive and 68% for the silage with chemical additive. All biogenic amines under investigation were present in low dry matter (140g/kg) silages, prepared without an additive. The content of histamine was the highest (5.24 g/kg DM), followed by putrescine (0.86 g/kg DM). Wilting and treatment with additive significantly decreased the formation of biogenic amines in silages.

Legumes are known to be difficult to ensile because they are highly buffering, have a low sugar concentration and often a low dry matter concentration. The previous results have shown that fermentation quality can easily be improved by using additives. The chemical composition, nutritive value and digestibility of silage prepared from the early-maturing red clover (Trifolium pratence L. subvar. praecox Witte) varieties 'Varte' (4x) and 'Jogeva 433' (2x); the late-maturing red clover (Trifolium pratence L. subvar. serotinum Witte) varieties 'Ilte' (4x) and 'Jogeva 205' (2x); hybrid lucerne (Medicago varia Mart) varieties 'Karlu' and 'Jogeva 118' in different phases of development were studied in 2000 and 2001. For this purpose, test silages were prepared. Legumes were cut at the height of 5 cm, chopped into 2 cm pieces, supplemented with additive AIV 2000 and conserved into jars. In 90 days the jars were opened; the chemical composition of test silages was determined according to the generally accepted methods, and nutritive value was calculated. The dry matter degradability of silages, as well as organic matter digestibility, was determined in vitro, using ANKOM analysers. Comparison of the chemical composition and nutritive value of different varieties of red clover and hybrid lucerne bred in Estonia revealed the following results. At the bud formation stage, the crude protein content of the tetraploid red clover variety 'Varte' was considerably higher (197 g/kg), and that of the crude fiber was lower (208 g/kg), compared with other varieties. Due to the extremely low dry matter content 122 to 130 g/kg at the bud formation and 145 to 148 g/kg at the stage of early flowering, the tetraploid red clovers should be wilted for ensiling. The metabolizable energy content of silage of the red clover and hybrid lucerne varieties was from 9.1 to 10.1 MJ/kg, respectively, of the stage of growth, and the organic matter digestibility - from 57 to 71 %.

Protein degradability of legumes. Kinetics of ruminal protein degradability of fresh lucerne and red clover, and that of silage prepared from them, also the effects of legume species, variety and additive on silage degradability were studied. Test silage from hybrid lucerne varieties 'Karlu' and 'Jõgeva 118', and from red clover varieties 'Jõgeva 433', 'Varte', 'Jõgeva 205' and 'Ilte' were conserved into 3-litre jars at early bloom stage. Protein degradability was investigated by the method of in sacco with fistulated cows. The protein degradability of fresh grass and that of silage from the same material are different. The effective degradability of fresh red clover was 67% and that of red clover silage 75%; the same values for hybrid lucerne were 77% and 85%, respectively. The effective protein degradability of silages from different lucerne varieties varied from 82 to 85% and that from red clover varieties from 74 to 77% at the same stage of development. A chemical additive slowed down silage protein degradability in the rumen to 16 incubation hours and decreased the effective degradability by 2%, compared to the silage prepared without an additive. Silage protein degradability in the rumen is affected by legume species and to a lesser degree by a variety.

Due to the low fermentation coefficient (27.5) of red clover-timothy mixture, it is necessary to use additives in order to make high-quality silage from it. The objective of the study was to select a proper biological additive for ensiling red clover-timothy mixture. DM losses during silage fermentation, organic matter digestibility and fermentation quality were studied. Test silages were ensiled in 3-litre jars. Four different biological silage additives I-1, I-2, I-3, I-4, and chemical additive AIV 2000 were used. The use of biological or chemical additives decreased silage DM losses by 2.1 to 3.1 times. DM losses were the lowest (7.7%) when additive I-3 was used. Treatment with biological additive with lactic acid bacteria concentration 8×109 cfu/g significantly improved the fermentation quality of clover-timothy silage: pH 4.0-4.1, ammonia-N in TN 1.1-2.0%, lactic acid content 43-71 g/kg and butyric acid content 0-3 g/kg in DM. Organic matter digestibility of the treated silage improved up to 10% as compared to that of the untreated silage (P<0.0001). All studied biological additives improved ensilability of the red clover-timothy mixture with low DM content. Biological additive I-3 appeared to be the most suitable for treating that kind of silage material.

Ruminal degradability of clover-grass mixtures and silages. The objective of the study was to determine the nutritive value of fresh mixtures and silage of red clover and grass (75% and 50% red clover), and to study degradability kinetics of crude protein and neutral detergent fibre (NDF) in the rumen. It was investigated to which extent the value of effective protein degradability is affected by the washing loss of feed particles from nylon bags, by microbial contamination and passage rate. In sacco experiments with fistulated cows were arranged. Feed samples were incubated in the rumen for 2, 4, 8, 16, 32 and 64 hours. According to the nutrients degraded in different incubation hours, the effective degradability of protein and NDF was calculated. The experiment revealed that protein degradability was more rapid in silage than in fresh grass. In 8 hours more than 50% of the protein of the fresh clover-grass mixture was degraded. In two incubation hours 78.2% of protein of test silage 1 prepared from the same material (75% clover) and 76.8% of test silage 2 (50% clover) was degraded. The effective protein degradability of fresh clover-grass mixture 1, the test silage and silage with AIV-2000 was 64.4%, 85.2% and 79.7%, respectively. In mixture 2 these values were 68.0%, 83.8% and 78.0%, respectively. Effective degradability of NDF in clover-grass silages ranged between 28.7 and 33.9%. As the result of the washing loss of feed particles from nylon bags, the effective protein degradability increased by 1.6 to 1.8% in grass and by 4.1 to 4.6% in silages. In calculating effective degradability it is necessary to choose the right passage rate. At a passage rate of 8% per hour, the effective degradability of the fresh clover- grass mixture 1 was by 18% and in test silage by 15.4% lower than at a passage rate of 5% per hour.