Effect of microbial inoculants on fermentation quality and aerobic stability of sweet potato vine silage.

OBJECTIVE: This study was conducted to evaluate the effect of homo or hetero fermentative inoculants on fermentation quality and aerobic stability of sweet potato vine (SPV) silage containing Italian ryegrass hay as moisture absorbent. METHODS: The SPV was harvested at 15% dry matter, mixed with Italian ryegrass hay at 1:1 ratio on a fresh weight basis, and chopped to 3 to 5 cm length. After then, the chopped forage mixture was ensiled into 20-L mini silos in quadruplicate for 7, 48, and 100 days after application of microbial inoculants at 1.2×105 colony forming units (cfu)/g of forage following: no inoculant (CON), Lactobacillus plantarum as a homo fermentative (LP), Lactobacillus buchneri as a hetero fermentative (LB), and mixture of LP and LB at 1:1 ratio as a combo fermentative (MIX). RESULTS: The LP and MIX silages had lowest pH (p<0.001) on 7 and 48 days, while MIX and CON silages had greatest lactate concentrations (p<0.05) on 7 and 48 days, respectively. Acetate concentrations were highest (p<0.01) in LB and MIX silages on 7 days, and in LB silage on 48 days, while lactate to acetate ratios were lowest (p<0.001) in LB silages. The chemical compositions and nutrient digestibility of silage ensiled for 100 days was not affected by inoculants. On 100 days of ensiling, LB silage had lowest (p<0.01) lactate concentration and lactate to acetate ratio, but highest acetate concentration. Aerobic stability was highest (p<0.001) in LB silage followed in MIX silage. On contrast, LB silage had lowest (p<0.05) lactic acid bacteria and mold. CONCLUSION: The results indicated that application of LB solely had a better effect on aerobic stability than not only LP, but also MIX. However, LP application did not show beneficial effects from the viewpoints of fermentation quality and aerobic stability compared to CON.

Effects of Different Cutting Height on Nutritional Quality of Whole Crop Barley Silage and Feed Value on Hanwoo Heifers.

The present study evaluated the effects of different cutting height on nutritive value, fermentation quality, in vitro and in vivo digestibility of whole crop barley silage. Whole crop barley forage (Yuyeon hybrid) was harvested at height of 5, 10, and 15 cm from the ground level. Each cutting height was rolled to make round bale and ensiled for 100 days. After 100 days of ensiling, pH of silage was lower (p<0.05) in 5 cm, but no difference between 10 and 15 cm of cutting height. The content of lactate and lactate to acetate ratio were increased (p<0.05) in 5 cm of cutting height, whereas the acetate content was higher (p<0.05) in 10 and 15 cm than that of 5 cm cutting height. Aerobic stability was greater (p<0.05) in silages of 10 and 15 cm of cutting height. Three total mixed rations (TMR) were formulated with silages from the three different cutting heights (TMR5, TMR10, and TMR15) incorporated as forage at 70:30 ratio with concentrate (dry matter [DM] basis). In vitro dry matter digestibility was higher (p<0.05) in the TMR5 and TMR10 than that in TMR15, whereas in vitro neutral detergent fiber digestibility was higher (p<0.05) in the TMR10 and TMR15 than that in TMR5. Concentration of NH3-N was highest (p<0.05) in the TMR10 followed by TMR15 and TMR5. Total volatile fatty acid was decreased (p<0.05) with increased cutting height. The digestibility of DM and neutral detergent fiber were highest (p<0.05) in TMR15, than those in TMR5 and TMR10, whereas acid detergent fiber digestibility was higher (p<0.05) in TMR5 than that in TMR10. The results showed that increasing cutting height, at least up to 10 to 15 cm, of whole crop barley forage at harvest (Yuyeon) may be beneficial for making silage for TMR formulation and increasing digestibility of DM and NDF.

Effect of Microbial and Chemical Combo Additives on Nutritive Value and Fermentation Characteristic of Whole Crop Barley Silage.

This study was conducted to assess the effects of microbial and chemical combo additives on nutritive values, fermentation indices and aerobic stability of whole crop barley silage. Barley forage (Youngyang) was harvested at about 30% dry matter (DM) by treatments, chopped to 5 cm length and treated with distilled water only (CON), Lactobacillus plantarum (INO), propionic acid (PRO) or an equal mixture of INO and PRO (MIX). Barley forages were ensiled in 4 replications for 0, 2, 7, and 100 days. On 100 days of ensiling, MIX silage had higher (p<0.05) in vitro DM digestibility than CON silage, but lower (p<0.05) acid detergent fiber concentration. The pH in all treated silages was lower (p<0.05) than CON silage. The MIX silage had higher (p<0.05) lactate concentration and lactate to acetate ratio than in CON, but lower (p<0.05) yeast count. Aerobic stability in CON, PRO, and MIX silages were higher (p<0.05) than in INO silage. It is concluded that microbial and chemical combo additives using L. plantarum and propionic acid could efficiently improve nutritive values of barley silage in terms of increased in vitro DM digestibility compared to other treatments. In addition, all treatments except CON reduced yeast count which is the initiate microorganism of aerobic spoilage.

Feeding of processed vegetable wastes to bulls and its potential environmental benefit.

The study was conducted with the objectives to quantify year round availability of different vegetables waste (VW) in a wholesale market and to determine the inclusion level of a processed VW (VWP) in the diets of bulls. The daily VW biomass availability at Kawran bazaar, Dhaka, Bangladesh was quantified by weighing the vegetable supply and their wastes by visiting 2 days in a week. Concurrently, VW of cucumber, bitter gourd, spotted gourd, brinjal, pumpkin, potato, tomato, ladies finger, and snake gourd representing 0.21, 0.18, 0.17, 0.16, 0.09, 0.07, 0.06, 0.03, and 0.02 as fresh fractions, respectively were blended, dried and stored while adding rice polish and common salt at 200 and 20 g/kg DM, respectively; it was tested in bulls as an ingredient of concentrate mixture. Four dietary groups, each of 6 bulls, with initial average live weight (LW) of 85.47 ± 17 kg, were fed fresh German grass (Echinochloa polystachya) ad libitum supplemented with 4 different concentrates containing 0, 10%, 20% and 30% VWP at the rate of 1% of LW for 89 days. The availability of VW biomass of the market was 42.51 t/d and recycling of them as feed, instead of using landfills, might reduce annual methane emission by 0.43 Gg. The inclusion of VWP in the diet up to 9.7% of DM, or 0.30% of LW of bulls showed no significant effect on the DM intake, digestibility, growth performance and health status of bulls. The dietary DM intake represented 3.10%, 3.09%, 3.20% and 3.14% of LW resulting in daily gain of 302, 300, 312 and 344 g, respectively. The digestibility of DM of diets was 56.9%, 62.8%, 62.8% and 63.4%, respectively. It was concluded that VWP may be included at a level of 9.7% of the diet (DM basis) or 0.30% of LW of bulls.

Effects of hybrid and bacterial inoculation on fermentation quality and fatty acid profile of barley silage.

This study estimated the effects of hybrid and bacterial inoculant on fermentation quality and fatty acid profile of barley silages. Yuyeon (Silkless) and Youngyang (Silking) barley hybrids were harvested at 24.9 and 27.1% dry matter, respectively, and chopped to 10 cm lengths. Each hybrid was treated with or without an inoculant (2 × 104  colony-forming units/g of Lactobacillus plantarum). A total of 48 silos were prepared in an experiment with a 2 × 2 (hybrid × inoculant) treatment arrangement with four replications and three ensiling durations (2, 7 and 100 days). After 100 days of ensiling, Yuyeon silage had higher (P < 0.05) in vitro dry matter digestibility and C18:3n-3 than Youngyang silage. Youngyang silage had higher (P < 0.05) acetic acid and C18:2n-6 than Yuyeon silage. Inoculation reduced the C18:3n-3 concentration of both hybrids and increased (P < 0.05) the C18:2n-6 of Youngyang. However, fermentation quality was not improved by the inoculant. These results indicate that Yuyeon hybrid might have better potential benefits on animal performances due to its smooth awn and silkless nature, and higher in vitro dry matter digestibility. Its higher C18:3n-3 would be better for improving fatty acid profile of meat or milk than Youngyang hybrid.

Effects of dietary n-6/n-3 fatty acid ratio on nutrient digestibility and blood metabolites of Hanwoo heifers.

The objectives of this study were to investigate the effects of dietary n-6/n-3 fatty acid (FA) ratio on digestibility, blood metabolites and FA profile of Hanwoo heifers. Fifteen Hanwoo heifers (22 ± 3 months old; 357 ± 69.7 kg) were randomly assigned to three dietary treatments with n-6/n-3 FA ratios of 2.07, 5.18 and 7.37. The animals were housed individually in digestion crates and fed total mixed rations at 2.2% of body weight for 2 weeks of adaptation and 1 week of collection. Treatment effects on in vivo digestibility, plasma metabolite and fatty acid profiles, and in vitro ruminal fermentation and fatty acid profiles were examined. In vivo digestibility was not affected (P > 0.05) by dietary n-6/n-3 FA ratio. However, in vitro dry matter digestibility and concentrations of total volatile fatty acids and propionate decreased (P < 0.05) linearly with increasing n-6/n-3 FA ratio. Plasma insulin and progesterone increased linearly (P < 0.05), but linolenic acid and total n-3 FA decreased linearly (P < 0.05) with increasing n-6/n-3 ratio. Increasing the dietary n-6/n-3 FA ratio can increase the n-6/n-3 FA ratio in plasma and ruminal fluid as well as plasma progesterone secretion.

Effects of fermented persimmon extract supplements on chemical composition and fermentation characteristics of barley silage.

This study was conducted to estimate the effect of fermented persimmon extract (FPE) supplementation levels on chemical composition and fermentation characteristics of barley silage. Barley forage was harvested at 25% dry matter and chopped to 5 cm lengths. The FPE was applied at 0, 0.4, 0.8 and 1.6 g/kg of barley forage (fresh weight basis). After sub-sampling of barley forages (0 day), a total of 64 laboratory mini silos (5 kg capacity) were ensiled to generate quadruplicate data from each of four treatments for four ensiling durations (2, 6, 40 and 120 days). The chemical compositions and in vitro digestibility of barley forage (0 day) were not affected by FPE supplementation. However, the content (L, P = 0.035) and in vitro digestibility (L, P = 0.041) of neutral detergent fiber on 120-day barley silage decreased by increasing FPE supplements. Acetate content of barley silage ensiled for 120 days increased (Q, P = 0.004) by increasing FPE supplements, whereas pH (L, P < 0.001), lactate content (Q, P < 0.001) and lactate-to-acetate ratio (Q, P < 0.001) decreased. These results indicate that addition of FPE can increase the acetate content which has potential to increase aerobic stability.