No abstract

The objective of this study was to evaluate the in vitro effects of organic acids on methane emission and ruminal fermentation characteristics. We expected our methodology to result in a decrease of methanogens attached to the surface of rumen ciliate protozoa by addition of organic acids and in particular a decrease in methane emission. A fistulated Holstein cow of 650 kg body weight was used as a donor of rumen fluid. Organic acids (aspartic acid, fumaric acid, lactic acid, malic acid, and succinic acid) known to be propionate enhancers were added to an in vitro fermentation system and incubated with rumen fluid. The microbial population, including bacteria, protozoa, and fungi, were enumerated, and gas production, including methane and fermentation characteristics, were observed in vitro. Organic acids appeared to affect the rumen protozoan community. The rumen protozoal popuation decreased with the addition of aspartic acid, fumaric acid, lactic acid, and malic acid. In particular, the methane emission was reduced by addition of lactic acid. The concentration of propionate with all organic acids that were added appeared to be higher than that of the control at 12 h incubation. Addition of organic acids significantly affected rumen bacteria and microbial growth. The bacteria in added fumaric acid and malic acid was significantly higher (p<0.05) and protozoa was significantly lower (p<0.05) than that of the control. Microbial growth with the addition of organic acids was greater than the control after 48 h incubation. [2,4,13,18]. 그리고 propionic acid전구물질은 H2를 제거하고 [19], 섬유소 분해 bacteria와 cellulose분해율을 증가한다고 알 려져 있다 [2,18]. 따라서, 본 연구의 목적은 여러 가지 organic acids를 첨가하여 in vitro 반추위 발효 성상, 건물소화율, 반추 위 혐기성 미생물 수(bacteria, fungi 및 protozoa) 및 메탄생성 에 미치는 영향과 기작을 규명하고자 한다.

The objective of the present study was to determine standardized total tract digestibility of phosphorus (P) in black soldier fly (BSF; Hermetia illucens) larvae fed to pigs. Test ingredients were fish meal (66.2% crude protein, 9.2% ether extract, and 2.63% P), 3 sources of defatted BSF larva meal (43.1 to 59.2% crude protein, 8.6 to 13.2% ether extract, and 0.91 to 1.06% P), and a source of full-fat BSF larva (34.2% crude protein, 36.0% ether extract, and 0.70% P). Six barrows with an initial mean body weight of 78.1 kg (SD = 1.0) were individually housed in metabolism crates. Six diets were assigned to the 6 pigs in a 6 × 7 Latin square design with 7 periods resulting in 7 replicates for each treatment. Five experimental diets contained fish meal, defatted BSF larva meal, or full-fat BSF larva at 25% as the sole source of P. Additionally, a P-free diet mainly based on corn starch, sucrose, and gelatin was also prepared to estimate the basal endogenous losses of P. After a 4-day adaptation period, feces were collected for 4 days according to the marker-to-marker procedure. Apparent total tract digestibility of P in full-fat BSF larva (61.9%) was greater (P &lt; 0.05) than that in 2 sources of defatted BSF larva meal (34.8% and 31.5%). Standardized total tract digestibility of P in full-fat BSF larva (71.8%) was greater (P &lt; 0.05) than that in fish meal (51.0%) or 2 sources of defatted BSF larva meal (41.0% and 38.9%). The basal endogenous losses of P were estimated to be 189 ± 62 mg per kg dry matter intake. In conclusion, P in defatted BSF larva meal was less digestible compared with full-fat BSF larva.

The objectives were to determine the digestible energy (DE) and metabolizable energy (ME) concentrations in black solider fly (BSF; Hermetia illucens) larvae fed to pigs and to develop prediction equations for energy in BSF larvae. On a dry matter (DM) basis, 4 sources of defatted BSF larva meal contained 4,402 to 5,173 kcal/kg gross energy (GE), 46.5 to 62.0% crude protein (CP), 9.0 to 14.3% ether extract (EE), and 13.7 to 25.3% ash and a source of full-fat BSF larva contained 5,875 kcal/kg GE, 36.5% CP, 38.5% EE, and 16.3% ash. Six barrows with an initial body weight of 73.1 kg (SD = 2.3) were individually housed in metabolism crates. Six diets were assigned to the 6 pigs in a 6 × 7 Latin square design with 7 periods. A basal diet was composed of 97.6% corn as the sole energy source. Five experimental diets were prepared by replacing 25% of corn with BSF larva. Each period consisted of a 4-day adaptation period and a 4-day collection period for feces and urine collection. The DE and ME values in full-fat BSF larva (4,908 and 4,761 kcal/kg DM) were greater (P &lt; 0.05) than those in defatted BSF larva meal (3,791 to 4,269 kcal/kg DM and 3,577 to 3,878 kcal/kg DM). Energy prediction models developed for BSF larva were: GE (kcal/kg DM) = 5,707 + 36.2 × EE – 74.2 × ash (R2 = 0.98); DE (kcal/kg DM) = 4,575 + 29.1 × EE – 47.9 × ash (R2 = 0.99); and ME (kcal/kg DM) = 3,852 + 36.5 × EE – 30.0 × ash (R2 = 0.99) where chemical components are expressed as % DM. Overall, full-fat BSF larva contained greater energy concentrations compared with defatted larva meal and energy concentrations in BSF larva ingredients can be estimated using EE and ash concentrations.

The objective was to determine the influence of feed intake (FI) and fiber source on hindgut disappearance of energy and nutrients in pigs. Ten canulated barrows with an initial body weight (BW) of 38.3 ± 5.4 kg were allotted to a replicated 5 × 4 Latin square design with 5 treatments and 4 periods. A corn-soybean meal-based basal diet (BD) and 2 × 2 factorial treatment arrangement with 2 amounts of FI (9.0 and 4.5% × BW0.75) and 2 fiber sources of sugar beet pulp (SBP) and corn cob were used. Three diets were 1) a BD, 2) a diet replacing 30% of corn and soybean meal in BD with SBP as a source of soluble dietary fiber (SDF), and 3) a diet replacing 15% of corn and soybean meal in BD with corn cobs as a source of insoluble dietary fiber (IDF) to obtain a similar IDF concentration as in the SBP diet. Each period consisted of 7-d adaptation, 2-d fecal collection, and 2-d ileal collection. Apparent ileal digestibility (AID) of energy, dry matter (DM), organic matter (OM), and crude protein (CP) in SBP diet was less (P &lt; 0.001) than that in corn cob diet, whereas AID of neutral detergent fiber in SBP were greater (P &lt; 0.001) than in corn cob diet. Hindgut disappearance of energy, DM, OM, neutral detergent fiber, and acid detergent fiber in SBP diet was greater (P &lt; 0.05) than that in corn cob diet. However, no interaction between FI and fiber source on the AID, apparent total tract digestibility, and hindgut disappearance of nutrients was observed. Overall, hindgut disappearance of nutrients in sugar beet pulp diet was greater than that in corn cob diet. However, the influence of feed intake or the interaction between feed intake and fiber source was not observed.