• Journal of The Korean Society of Grassland and Forage Science
• /
• v.37 no.4
• /
• pp.308-314
• /
• 2017

This study was conducted with two ruminally cannulated Holstein steers to examine the effect of micronized and steam flaked corn on ruminal fermentation characteristics. The in situ dry matter degradability after 48 h incubation was the highest (P<0.05) at micronized corn (2.5 mm thickness) compared with steam flaked corn treatments. The steam flacked corn (3.3 mm thickness) was degraded lower (P<0.05) than the 2.9 and 3.1 mm thickness of steam flacked corn. Effective dry matter degradability and the rate of constant were the highest (P<0.05) at micronized corn (2.5 mm thickness) compared with steam flaked corns as well. The in vitro dry matter degradability after 48 h incubation was tended to higher (P=0.088) at micronized corn (2.5 mm thickness) than steam flaked corns, whereas there is no significantly difference between steam flaked corn treatments. Total volatile fatty acid concentration was higher at steam flaked corn (2.9 mm thickness) than micronized corn (2.5 mm thickness) and steam flaked corn (3.1 and 3.3 mm thickness). The acetate : propionate ratio was the highest (P=0.008) at steam flaked corn (2.9 mm thickness) and the lowest (P=0.008) at micronized corn (2.5 mm thickness). Total gas and methane production after 48h ruminal incubation was the highest (P=0.001) at micronized corn (2.5 mm thickness) compared with steam flaked corns. According to these results, the thickness of steam flaked corn as resulted corn processing is believed to do not affect methane production. However, further study is needed to better understand the present results to verify the correlation between corn processing method and their thickness on methane production using the same thickness corns by difference processing methods.

• Korean Journal of Agricultural Science
• /
• v.23 no.2
• /
• pp.188-205
• /
• 1996

This study was conducted to examine the effects of dietary energy and protein sources on the rumen microbial population of sheep. The results obtained were summarized as the follows; 1. Ruminal pH was highest in sheep fed the diet rapidly degraded in the rumen(F-F) as a energy (barley plus beet pulp) and protein source (rapeseed meal), and lowest in the diet (F-S) of rapidly degradable energy source plus slowly degradable protein source (corn gluten meal + cotton seed meal) without affecting by postfeeding time. 2. Ruminal ammonia concentration was higher in corn (slowly degradable) for energy source and rapeseed meal (rapidly degradable) for protein source (S-F) than others, and abruptly increased at 1 hr after feeding regardless of treatments. 3. Concentration of ruminal total volatile fatty acid, acetate and propionate were highest in F-S and peaked at 1 hr after feeding firstly and formed second peak at 9hrs, respectively. 4. Digestibilities of the proximates and ADF were not affected by treatment but NDF was highest in F- F. 5. Nitrogen retention was highest in S-F and lowest in F-F and F-S. 6. Digestibility and metabolizability of energy, contents of OCP, TDN, DE and ME were not affected by treatment.

• Korean Journal of Agricultural Science
• /
• v.32 no.1
• /
• pp.43-51
• /
• 2005

This study was carried out to investigate the style of livestock house, concentration of malodorous substances of livestock feces and livestock houses in Daejeon area. Among the livestock houses investigated, as most of cow pens(94.5%) have sawdust or chaff on the bottom, there was no leakage of feces out of pen. Most pig pens adopted slury style, but some of them currently use buffering material on the bottom. It is thought that there will be no possible contamination leakage. When it comes to hen house, all the broiler house use litters on the bottom and all the layer house use scrapper. It is also thought that there will be no possible contamination leakage. 3 out of 12 deer pens used buffering material on the bottom, 10 places were maintained in a traditional method, and 7 places left possibility of contamination leakage considering whether the roof was installed or not. The contents of ammonia, amine and volatile fatty acid in fresh feces were lower compared to rotten feces, but the concentration of sulfur-containing matter - hydrogen sulfide, methylmercapthan and ethylmercapthan were higher compared to rotten feces. In the case of malodorous ingredient in livestock houses, only small amount of ammonia and hydrogen sulfide were detected in pig pen and hen house, and other ingredients were not detectable. And those who are engaged in animal husbandry reacted negatively to the use of feed additives for decreasing malodor. In conclusion, it is not worrisome that contamination can be leaked out of animal raising facilities. But if we take into consideration that the point of investigation time is wintry season, there should be more considerate attitude. And feed additives for decreasing malodor need establishing criteria in the manufacturing process.

• Food Science of Animal Resources
• /
• v.30 no.2
• /
• pp.277-285
• /
• 2010

The objective of this study was to manufacture spent layer chicken meat products by natural freeze-drying. The spent layers of chickens that were slaughtered at 80 wk were obtained from a local slaughter house and separated into two halves of carcasses. The samples were divided into the following groups: 1) control (non-curing), 2) curing, and 3) curing with 2% trehalose before drying. The cured meats were placed at $2^{\circ}C$ for 7 d and then transferred to a natural drying spot located in Injae City, Gangwondo, Korea. The experiment was conducted from January to March in 2008. The average temperature, RH, and wind speed were $-1.5^{\circ}C$, 63%, and 1.8 m/sec, respectively. The cured treatments showed higher pH, lower Aw and lower shear force value compared with the control. Based on the results of TBARS (2-thiobarbituric acid reactive substances) level and volatile basic nitrogen value, lipid oxidation and protein deterioration were inhibited in curing treatments during drying. Trehalose acted as a humectant because it maintained a lower water activity despite the relatively higher moisture content during drying. The polyunsaturated fatty acids content and sensory attributes were higher in cured treatments than in the control during drying. Most of the bacterial counts in the treated groups were lower by 2 Log CFU/g after 1 mon of drying, and Salmonella spp. and Listeria spp. were not found in any treatment. There was also no microbial safety problem associated with dried meat products. Based on the results of this experiment, dried meat products could be manufactured from precured spent layer chickens by natural freeze-drying during winter.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.40 no.4
• /
• pp.236-243
• /
• 2020

This study was to evaluate the feed value of whole crop rice silage (WCRS) and to investigate a suitable ratio of the WCRS and concentrate by an analysis of rumen fermentation. A total of 6 treatments were used according to WCRS: concentrate ratio on in vitro rumen fermentation: T1 (100:0), T2 (60:40), T3 (40:60), T4 (20:80), T5 (10:90), and T6 (0:100). The ruminal pH, total gas emission, ammonia nitrogen, and volatile fatty acid (VFA) were determined as fermentation parameters. Total nutrients digestibility trial was conducted by 4 treatments according to WCRS: concentrate ratio at 40:60 (W40), 20:80 (W20), and 10:90 (W10), respectively. Feed value was analyzed according to AOAC (2019) and nutrient digestibility was calculated based on NRC (2001). The levels of crude protein (CP), crude fat, and neutral detergent fiber of the WCRS were 12.29%, 1.67%, and 59.79%, respectively. It was found to be 51.49% as a result of predicting the total digestible nutrient of WCRS using the NRC (2001) model. In vitro rumen fermentation, T4, T5, and T6 treatments showed a greater gas emission and total VFA concentration compared with other treatments (p<0.05). Acetate and acetate to propionate ratio of T4, T5, and T6 were significantly higher than other treatments (p<0.05). There was a significant difference in the level of propionate and butyrate according to the WCRS: concentrate ratio (p<0.05). The digestibility of dry matter and CP was significantly lower in W40 than in other treatments (p<0.05); however, there was no difference in W20 and W10. In conclusion, the 20:80 (WCRS: concentrate) is beneficial for stabilizing the rumen that does not inhibit rumen fermentation and nutrient digestion. This ratio might have a positive effect on the economics of farms as a valuable feed.