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T, Fujihara T: Inorganic selenium for sheep II. Its influence on rumen bacterial yield, volatile fatty acid production and total tract digestion of timothy hay. Asian Australas J Anim Sci 1994, 7:91-96. 5. Kim J, Van Soest PJ, Combs Jr GF: Studies on the effects of selenium on rumen microbial fermentation in vitro. Biol Trace Elem Res 1997, 56:203–213. 6. Del Razo-Rodriguez OE, Ramirez-Bribiesca JE, Lopez-Arellano R, Revilla-Vazquez AL, Gonzalez-Munoz SS, Cobos-Peralta MA, Hernandez-Calva LM, McDowell LR: Effects of dietary level of selenium and grain on digestive


The aim of this study was to investigate the effect of pH on the dark fermentation process of kitchen waste by specifying the composition of the volatile fatty acids (VFA), H2 and by drawing the carbon balance. Studies were carried out in 8 dm3 batch bioreactor in mesophilic conditions. The kitchen waste from the city of Lodz were used as a substrate. Based on the study, it was observed that most of the VFA was produced during the first two days of the process, while in the following days the production was diminished. The highest production of VFA (19.5 g/dm3) was obtained in the bioreactor, where the pH was 7 and 8. Analyzing the produced VFA it was observed that mostly the acetic and butyric acid had been produced. Most of acetic acid (over 70 %) was obtained in fermenter with pH 7 and 8. In contrast, most of the butyric acid (over 40 %) was in the bioreactor with a pH of 6. Production of H2 was in the range from 4.29 to 26.5 dm3, wherein the largest amount of H2 was created in the bioreactor with a pH of 6.

). Experimental design and analysis. Blacksburg, USA, Valley Book Co., 2nd ed., 585 pp. Mc Reynolds J.L., Byrd J.A., Genovese K.J., Poole T.L., Duke S.E., Farnell M.B., Nisbet D.J. (2007). Dietary lactose and its effect on the disease condition of necrotic enteritis. Poultry Sci., 86: 1656–1661. Pierce K.M., Sweeney T., Brophy P.O., Callan J.J., Fitzpatrick E., Mc Carthy P., O’Doherty J.V. (2006). The effect of lactose and inulin on intestinal morphology, selected microbial populations and volatile fatty acid concentrations in the gastrointestinal tract of the weanling pig


The objective of this study was to determine the effects of geraniol and camphene at three dosages (300, 600, and 900 mg l-1) on rumen microbial fermentation and methane emission in in vitro batch culture of rumen fluid supplied with a 60 : 40 forage : concentrate substrate (16.2% crude protein, 33.1% neutral detergent fibre). The ionophore antibiotic monensin (8 mg/l) was used as positive control. Compared to control, geraniol significantly (P < 0.05) reduced methane production with increasing doses, with reductions by 10.2, 66.9, and 97.9%. However, total volatile fatty acids (VFA) production and in vitro dry matter digestibility were also reduced (P < 0.05) by all doses of geraniol. Camphene demonstrated weak and unpromising effects on rumen fermentation. Camphene did not decrease (P > 0.05) methane production and slightly decreased (P < 0.05) VFA production. Due to the strong antimethanogenic effect of geraniol a careful selection of dose and combination with other antimethanogenic compounds may be effective in mitigating methane emission from ruminants. However, if a reduction in total VFA production and dry matter digestibility persisted in vivo, geraniol would have a negative effect on animal productivity.


The aim of the research was to evaluate the effect of three Eucalyptus globulus extracts rich in phenolic compounds, especially flavonoids, on rumen fermentation, methane (CH4) production, organic matter degradability and protozoa population using an in vitro gas production technique. Four concentrations (0, 50, 75 and 100 mg) of three Eucalyptus extracts (ethyl acetate, n-butanol and aqueous) were added to a diet of ruminants (forage: concentrate ratio 60:40) and incubated at 39°C under anaerobiosis with buffered rumen fluid. After 24 h, the fermentation fluid was analysed for ammonia-N and volatile fatty acids (VFA). Organic matter degradability (OMD) and protozoa were also determined; in vitro gas production was also recorded and CH4 concentration was measured. Compared to the control, CH4 production was significantly lower for ethyl acetate extract (P<0.05), but higher for n-butanol and aqueous extracts. Production of ammonia- N was lower in all Eucalyptus extracts (P<0.05). Propionate production (P<0.05) increased for ethyl acetate and n-butanol extracts, whereas no effect was registered for VFA, for all Eucalyptus extracts. Ethyl acetate extract decreased in vitro OMD (P<0.05), whereas n-butanol and aqueous extracts were comparable to the control. Protozoa population decreased (P<0.05) for all extracts in comparison with the control. Eucalyptus ethyl acetate extract might be promising to be used as a potent anti-methanogenic additive. Moreover, the assessment of the right dosage seems to be important to decrease methane production, without reducing feed nutritional value.

:// utilization-and-reduction/dietary-possibilities-to-mitigate-rumen-methane-and-ammonia-production. Szumacher- Strabel M., Cieślak A. (2010). Potential of phytofactors to mitigate rumen ammonia and methane production. J. Anim. Feed Sci., 19 (3): 319-337. Szumacher- Strabel M., Potkański A., Kowalczyk J., Cieślak A., Czauder- na M., Gubała A., Jędroszkowiak P. (2002). The influence of supplemental fat on rumen volatile fatty acid profile, ammonia and p Hlevel in sheep fed standard diet. J. Anim. Feed Sci., 11: 577-587. Tangerman A., Nagengast F.M. (1996). Agas chromatographic

Effect of Thermal Disintegration of Excess Sludge on the Effectiveness of Hydrolysis Process in Anaerobic Stabilization

The factor which essentially affects sludge biodegradation rate is the degree of fluidization of insoluble organic polymers to the solved form, which is a precondition for availability of nutrients for microorganisms. The phases which substantially limit the rate of anaerobic decomposition include hydrolytic and methanogenic phase.

Subjecting excess sludge to the process of initial disintegration substantially affects the effectiveness of the process of anaerobic stabilization. As a result of intensification of the process of hydrolysis, which manifests itself in the increase in the value and rate of generating volatile fatty acids (VFA), elongation of methanogenic phase of the process and increase in the degree of fermentation of modified sludge can be observed. Use of initial treatment of sewage sludge i.e. thermal disintegration is aimed at breaking microorganisms' cells and release of intracellular organic matter to the liquid phase. As a result of thermal hydrolysis in the sludge, the volatile fatty acids (VFA) are generated as early as at the stage of the process of conditioning. The obtained value of VFA determines the course of biological hydrolysis which is the first phase of anaerobic stabilization.

The aim of the present study was to determine the effect of thermal disintegration of excess sludge on the effectiveness of the process of hydrolysis in anaerobic stabilization i.e. the rate of production of volatile fatty acids, changes in the level of chemical oxygen demand (COD) and increase in the degree of reduction in organic matter. During the first stage of the investigations, the most favourable conditions of thermal disintegration of excess sludge were identified using the temperatures of 50°C, 70°C, 90°C and heating times of 1.5 h - 6 h. The sludge was placed in laboratory flasks secured with a glass plug with liquid-column gauge and subjected to thermal treatment in water bath with shaker option. Another stage involved 8-day process of anaerobic stabilization of raw and thermally disintegrated excess sludge. Stabilization was carried out in mesophilic temperature regime i.e. at 37°C, under periodical conditions. In the case of the process of anaerobic stabilization of thermally disintegrated excess sludge at the temperature of 50°C and heating time of 6 h (mixture B) and 70°C and heating time of 4.5% (mixture C), the degree of fermentation of 30.67% and 33.63%, respectively, was obtained. For the studied sludge, i.e. mixture B and mixture C, maximal level of volatile fatty acids i.e. 874.29 mg CH3COOH/dm3 and 1131.43 mg CH3COOH/dm3 was found on the 2nd day of the process. The maximal obtained value of VFA was correlated on this day with maximal COD level, which was 1344 mg O2/dm3 for mixture B and 1778 mg O2/dm3 for mixture C.


This study was conducted to determine the effects of a low-protein diet supplemented with synthetic amino acids on the biochemical parameters in the blood serum, the indicators of fermentation processes, and nitrogen excretion in 12 crossbred piglets. The piglets (weaned at 28 days of age) were divided into two groups with 6 piglets each. The control group had an initial average body weight of 8.8 ± 0.6 kg and the experimental group with an average initial body weight of 8.6 ± 0.7 kg. The control diet contained 210.8−1 crude protein and the experimental diet contained 186.4−1. The experimental diet was supplemented with lysine, methionine and threonine to achieve a more ideal amino acid pattern. The blood collections from the sinus ophthalmicus for the determination of the biochemical parameters were performed 4 times at weekly intervals in the control and experimental groups 4—5 hours after feeding. The faeces were taken from the rectum at the end of the study period. The decrease in the dietary crude protein content of the experimental group was manifested by a significant decrease of the blood urea level (2.61 mmol.l−1 average concentration) compared to the control groups (4.21 mmol.l−1 average concentration) (P < 0.001). The other serum component concentrations (total protein, albumin, glucose, cholesterol, total lipids and selected enzymes) showed no significant statistical changes between the control and experimental groups. The results of the fermentation process analysis indicated that the butyrate concentration decreased (P = 0.0017) and the pH increased (P = 0.0180) in the experimental group compared to the control group. The levels of crude protein and ammonia in the faeces of experimental animals were significantly lower (P < 0.001) in comparison with those in the control animals.

Knapen F. (2000). Role of volatile fatty acids in development of the cecal microflora in broiler chickens during growth. Appl. Environ. Microbiol., 66: 2536-2540. Van Immerseel F., De Buck J., De Smet I., Pasmans F., Haesebrouck F., Ducatelle R.. (2004). Interactions of butyric acid and acetic acid-treated Salmonella with chicken primary cecal epithelial cells in vitro. Avian Dis., 48: 384-391. Vicente J., Wolfenden A., Torres-Rodriguez A., Higgins S., Tellez G., Har- gis B. (2007). Effect ofa Lactobacillus species-based probiotic and dietary lactose prebiotic on

effect of inclusion of oat hulls in piglet diets based on raw or cooked rice and maize. Anim. Feed Sci. Technol., 135: 100-112. OlivaresM., Díaz- Popero M.P., Gómez N., Sierra S., Lara - Villoslada F., MartínR., Rodríguez J.M., Xaus J. (2006). Dietary deprivation of fermented foods causes a fall in innate immune response: Lactic acid bacteria can counteract the immunological effect of this deprivation. J. Dairy Res., 22: 1-7. Parker D.S. (1976). The measurement of production rates of volatile fatty acids in the caecum of the conscious rabbit. Br. J. Nutr., 36: 61