This study was conducted to know effects of forage cutting height and inoculants application on chemical composition, fermentation characteristics and fatty acid profile of barley silage. Barley forage(Yuyeon hybrid) was harvested at two different cutting heights(5 vs. 15cm) and applied with or without Lactobacillus plantarum, and ensiled for 0, 2, 7, 28, 49 and 100days. On 0 to 49-d of ensiling, higher cutting height resulted rapid drop (p<0.05) in pH caused by higher lactate content. Crude protein (p<0.01) content of 100-d silage was decreased by inoculation, but increased by higher cutting height. However, neutral detergent fiber and acid detergent fiber contents were decreased (p<0.05) by both inoculation and cutting height. In vitro dry matter digestibility was improved by higher cutting height (p=0.01), while yeast and mold counts were reduced (p<0.0001). The C18:3n-3 content in barley silage was decreased (p=0.001) by inoculation, but increased (p=0.034) by higher cutting height. The DNA analysis indicated L. plantarum dominating fermentation in inoculated silages. The results showed that higher cutting height can improve silage quality in terms of increasing crude protein content and digestibility as well as reducing yeast and mold counts in barley silage.
This study was conducted to examine the effect of dietary n-3/n-6 fatty acid (FA) ratio on in vitro dry matter digestibility (IVDMD), fermentation indices and FA profile. Rice bran was mixed with oil sources (cotton seed oil and linseed oil) to make the diets at 0.02, 0.29 and 0.61 of dietary n-3/n-6 FA ratio. These diets (0.5g) were placed into the incubation bottles with 40 ml of anaerobic culture medium, which contained rumen fluid and Van Soest medium at 1:2 ratio. Five replicates of each diet and two blanks were incubated at 39℃ for 48 hours. After incubation, the incubated contents were centrifuged. The residues were freeze-dried for DMD and FA analyses. The supernatant was used for pH, NH3-N and volatile fatty acid analyses. The concentrations of lactate (p<0.001) and iso-valerate (p<0.001) decreased linearly with increasing dietary n-3/n-6 FA ratio, but acetate concentration (p=0.056) and the ratio of acetate to propionate (p=0.005) was increased linearly. The concentrations of n-3, n-6 FA and the ratio of n-3/n-6 FA in residues increased (p<0.001) linearly with increasing dietary n-3/n-6 FA ratio, but C18:1n-9 FA concentration was decreased (p<0.001) linearly. With these results, it could affect fermentation characteristics and FA profile of rumen content by dietary n-3/n-6 FA ratio.
The effects of probiotic additions to feed and manure on temperature, humidity and carbon dioxide (CO2) emissions in Hanwoo manure during summer (4 weeks) were evaluated. Fifteen Hanwoo (24-mo-old, 580 ± 20 kg) were housed in individual pens (5 × 8 m) and randomly assigned to 1 of 3 treatments (n = 5 cattle per treatment). Hanwoo were fed experimental rations as follows: control (10 kg roughage + 2 kg concentrate); T1 (10 kg roughage + 2 kg concentrate, 2% probiotics on as-fed basis); and T2 (10 kg roughage + 2 kg concentrate, 2% probiotics on as-fed basis + 7 kg probiotics as top-dressing on the surface of Hanwoo manure). In comparison to the control, the addition of probiotics to feed or feed and manure had an effect (P < 0.05) on temperature and humidity over the 4 weeks, except for humidity at 0 weeks. The only significant difference (P < 0.05) observed in CO2 emission was among all treatments at 3 and 4 weeks (but not at 0 through 2 weeks). These results indicated that use of probiotics as feed and manure additives did not have a significant effect on environmental parameters.