Designing a Biogas Plant for an Educational and Scientific Livestock Complex

To design biogas plants, it is necessary to have accurate data about the properties and biogas productivity of the available substrates. Reference data should not be used because the performance of the same substrate can vary significantly. In this research,chicken, horse, sheep and rabbit manure from one of the farms inthe Belgorod region of Russia were analyzed, and the parameters of a biogas station for the processing of this raw material were calculated.The biogas yield of the substrates was determined using the Hohenheim Biogas Yield Test. It was found that the specific biogas yield from the droppings of broilers, laying hens, rabbits, sheep, and horses, and from corn silage were, respectively, 456, 363, 390, 189, 116 and 618 ml/g оDM. The methane content in the biogas was 58.00, 58.50, 57.00, 62.00, 65.00 and 53.60%, respectively. In most cases, the obtained results differed significantly from the data presented in publications of other researchers and reference books.The biogas plant parameter calculations were made according to generally accepted equations, taking into account the characteristics of the studied substrates. Based on the results, it can be concluded that to dispose of the animal excrement of this farm, it is necessary to build a biogas plant with a bioreactor of volume 102.2 m3 and an engine with a power of 12 to 31 kW. The planned output of electric and thermal energy would be 246.19 and 410.27 kWh/day, respectively. Keywords: Hohenheim Biogas Yield Test, rabbit manure, horse dung, sheep manure, chicken droppings, biogas yield of substrates

Effect of Various Strains of Lactobacillus buchneri on the Fermentation Quality and Aerobic Stability of Corn Silage

The aerobic deterioration of silage nutrients is inevitable in tropical countries, causing negative consequences in animal production systems. Aiming to minimize the losses, the effects of Lactobacillus buchneri strains on fermentation profile and aerobic stability of corn silages were evaluated. The experiment was conducted under a completely randomized design with 13 treatments and three replicates. The treatments were noninoculated, commercial L. buchneri (CI), and 11 wild strains of L. buchneri: LB-56.1, LB-56.2, LB-56.4, LB-56.7, LB-56.8, LB-56.9, LB-56.21, LB-56.22, LB-56.25, LB-56.26, and LB-56.27. The treatments could be divided into three different groups according to silage pH and acetic acid concentration. Silages inoculated with LB-56.1, LB-56.4, and LB-56.9 presented higher pH, whereas intermediate values were observed for LB-56.2, LB-56.7, and LB-56.8. The highest acetic acid production was observed for LB-56.1 and LB-56.7. On the other hand, lowest concentrations were found for CI, LB-56.22, LB-56.25, LB-56.26, and LB-56.27. Higher amounts of NH3–N were observed for LB-56.8, LB-56.21, LB-56.22, and LB-56.27 silages than others. Silage inoculation with CI, LB-56.1, LB-56.2, LB-56.4, LB-56.8, LB-56.9, and LB-56.25 strains had higher aerobic stability than others (59.7 vs. 41.2 h). The L. buchneri strains LB-56.1, LB-56.2, LB-56.4, LB-56.8, LB-56.9, and LB-56.25 provided potential features to improve the aerobic stability of corn silage.

Effect of Bacillus amyloliquefaciens and Bacillus subtilis on fermentation, dynamics of bacterial community and their functional shifts of whole-plant corn silage

Background Bacillus amyloliquefaciens (BA) and Bacillus subtilis (BS) are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals. However, few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling. If the BA and BS inoculants have positive effects on silages, then they could not only improve fermentation characteristics, but also deliver BA or BS viable cells to ruminants, which would play its probiotic effect. Therefore, the objectives of this study were to investigate the effects of BA and BS on the fermentation, chemical characteristics, bacterial community and their metabolic pathway of whole-plant corn silage. Results Freshly chopped whole-plant corn was inoculated without or with BA and BS, respectively, and ensiled for 1, 3, 7, 14 and 60 d. Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control, and BA inoculation decreased acetic acid concentrations, whereas BS inoculation decreased fiber contents and increased crude protein (CP) content. Higher water-soluble carbohydrate contents and lower starch contents were observed in BA- and BS-inoculated silages compared with that in control. The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage, which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage. In addition, it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins, and decreased the relative abundances of drug resistance: antimicrobial pathways. We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study. There were no significant differences in bacterial community compositions among the three groups during ensiling. However, BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter. Conclusion Our findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study.

Growth Rate and Bone Hydroxyproline Concentration in Turkeys Fed with a Silage-Composed Diet Modified with Different Diet Cation–Anion Differences (DCADs)

Our goal was to determine the responses of body weight (BW) and bone hydroxyproline (Hyp) concentration in turkeys fed a corn silage (CS) diet with different values of dietary cation–anion differences (DCADs). The turkeys (n = 90) were divided into five groups and fed as follows: group A (control)—standard diet (SD) (60%) plus CS (40%); group B—SD (60%), CS (40%) plus 240 g of CaCl2 per 100 kg of diet; group C—SD (60%), CS (40%) plus 480 g of CaCl2 per 100 kg of diet; group D—SD (60%), CS (40%) plus 240 g of NaHCO3 per 100 kg of diet; group E—SD (60%), CS (40%) plus 480 g NaHCO3 per 100 kg of diet. The addition of a lesser amount of CaCl2 lowered the DCAD, which ranged between 52.5 ± 4.19 and 91.14 ± 3.14 mEq/kg DM. An increased content of CaCl2 led to high negative values of DCAD. NaHCO3 supplemented in both doses resulted in a significant elevation of DCAD. Compared to each experimental group, feeding birds with a diet supplemented only with CS resulted in a lower BW. Addition of CaCl2 or NaHCO3 to the diet improved BW, but only CaCl2 addition enhanced the bone Hyp amount. In conclusion, we suggest that an anionic diet with low DCAD can prevent bone abnormalities in large turkeys, especially in the final course of production.

Evaluation of antimicrobial compounds to inhibit growth of select Gram-positive pathogenic or antimicrobial resistant bacteria in air-exposed silage

Spoiled silages can harbor pathogenic and antimicrobial-resistant microbes. The potential of some antimicrobial additives to inhibit certain pathogenic and antimicrobial-resistant bacteria in air-exposed silage was measured using pure and mixed bacterial cultures. With pure cultures, laurate and monolaurin (5 mg·mL−1) caused decreases (P < 0.05) of 4 to >7 log10 colony-forming units (CFU)·mL−1 in Listeria monocytogenes and Enterococcus faecalis compared to controls. Ten-fold higher amounts of these inhibitors were needed to equivalently decrease staphylococci. 2-Nitropropanol (1 mg·mL−1) decreased (P < 0.05) E. faecalis and L. monocytogenes 2.9–3.8 and 2.4–7.2 log10 CFU·mL−1 after 6 and 24 h incubations, respectively. In air-exposed whole-plant corn silage the inhibitors caused decreases, although not necessarily significant, of 0.7–2.2 log10 CFU·mL−1 in L. monocytogenes, staphylococci and culturable aerobes after 24 h incubation, with modest yet significant (P < 0.05) inhibition (<0.1–0.3 log10 CFU·mL−1) of yeasts and molds. Tests for carry-over effects against ruminal microbes revealed laurate, monolaurin, and 2-nitropropanol inhibited methanogenesis by >50% (P < 0.05) after 24 h incubation and inhibited L. monocytogenes and enterococci. The antimicrobial activities exhibited by these compounds may yield opportunities to optimize their use to rescue spoiled silages.

Metagenomic Analysis Reveals the Shared and Distinct Features of Bacterial Communities and Resistomes in Corn Silage from Different Climate Zones in China

Background: The emergence and spread of antibiotic resistance are a significant threat to global health. Silage is a major forage feed for ruminants, and its safety is an important guarantee that high-quality ruminant products will remain available to humans. However, little attention has been given to the silage resistome. To define the antibiotic resistome and its potential risk to silage from different climate zones and in response to the ensiling process, this study used metagenomics to investigate bacterial communities and the type and amount of antibiotic resistance gene (ARG) in corn silage harvested from six climate zones (Cfa, BWk, Dwc, Dwa, BSk, and Aw based on Köppen-Geiger climate classification) in China. Results: The composition and succession of silage bacterial communities varied significantly between different climate zones. Lactobacillus was the predominant bacteria during corn ensiling. A total of 134 ARGs were observed in corn silage, with the dominant classes being beta-lactamase and multidrug resistance and the primary mechanisms being efflux pump, inactivation, and target protection. Differences in the resistome were mainly attributed to disparities in microbial composition, which was indirectly affected by climatic factors and fermentation pH. ARG abundance was lower in 90-day silages than 5-day silages except in Hainan silage. The diversity and relative abundance (0.65-0.4% based on total gene number) of ARGs was lower in silage microbiota from Tibet than other climate zones. The dominant ARGs were tetM, oqxB, lmrD, lnuA, ermB, and tetS, and Enterobacter, Klebsiella, Staphylococcus, Lactobacillus and Lactococcus were the primary ARG hosts. Eleven high-risk ARGs were chosen to evaluate the pollution level of silages harvested from different climate zones. The highest relative abundance of high-risk ARGs belonging to Lactobacillus occurred in corn silages from Cfa, Dwa and BWk climate zones. Conclusions: The ensiling process decreased ARG abundance. While resistome contamination of silage from Tibet was relatively low, ARGs with high risk were abundant in silages from Cfa, Dwa and BWk climate zones.

Kinetics of In Vitro Gas Production and Fitting Mathematical Models of Corn Silage

This study aimed at examining the effects of rumen inoculum of steers receiving different combinations of ionophore and probiotics in their diets on in vitro gas production of corn silage. The fitting of gas production was performed with five mathematical models and its kinetics was evaluated. Four crossbred steers (403.0 ± 75.5 kg body weight) with ruminal cannula were assigned to a 4 × 4 Latin square design. The additives used were Monensin sodium (Rumensin® 100, 3 g/day), Bacillus toyonensis (Micro-Cell Platinum® 109, 1 g/day) and Saccharomyces cerevisiae boulardii (ProTernative®20, 0.5 g/day). Additives were arranged into the following treatments, supplied daily into total mixed diet: (1) Monensin; (2) Monensin + B. toyonensis; (3) Monensin + S. boulardii; and (4) B. toyonensis + S. boulardii. The gas production data were fitted into the models of Gompertz, Groot, Ørskov, Brody, Richards, and Dual-pool Logistic. A perfect agreement between observed and predicted values in curves of accumulated in vitro gas production was observed in the Groot and Richards models, with higher coefficient of determination (R2 = 0.770 and 0.771, respectively), concordance correlation coefficient (CCC = 0.871 and 0.870, respectively), and root mean square error of prediction (RMSEP = 1.14 and 1.15, respectively). Evaluating the feed additives throughout the Groot model, the B. toyonensis + S. boulardii treatment presented higher VF (12.08 mL/100 mg of DM; p = 0.0022) than Monensin and Monensin + S. boulardii (9.16 and 9.22 mL/100 mg of DM, respectively). In addition, the fractional rate of gas production (k) was higher (p = 0.0193) in B. toyonensis + S. boulardii than in Monensin, not presenting a statistical difference (p > 0.05) from the other two treatments. Additionally, with the time of beginning to gas production, the lag time (λ), was greater (p < 0.001) with Monensin and Monensin + B. toyonensis than with Monensin + S. boulardii and B. toyonensis + S. boulardii. The combination of Monensin and probiotics (B. toyonensis + S. boulardii) resulted in better kinetics of degradation of corn silage, being that the Groot and Richards models had the best fit for estimates of the in vitro gas production data of corn silage tested with different feed additive combinations.

The Effects of Replacing Dry Forage With Corn Silage on Milk Yield, Composition and Fatty Acids’ Profiles, Blood Metabolites, Nitrogen Balance, and Rumen Fermentation Parameters in Mahabadi Lactating Goats

The present study was performed with the aim of investigating the effects of replacing dry forage with corn silage on performance, milk yield, composition and fatty acids’ profiles, blood metabolites, nitrogen balance, and rumen fermentation parameters in Mahabadi lactating goats. For this purpose, a total of 20 lactating goats aged between 2 and 5 years old and with body weight of 45.3 ± 7.20 (DS) kg were categorized into two groups, each one containing ten goats. Experimental treatments consisted of controlling diet and dietary substitution of forage part with corn silage at 20% of dry matter. The obtained data were analyzed by the mixed model for a randomized completed design using statistical packages of SAS (2002). The replacement of dry forage with corn silage did not affect the dry matter intake (DMI), live body weight, and milk yield. Feeding corn silage, rather than dry forage, had no significant effect on milk unsaturated fatty acids, monounsaturated fatty acids, C18:1C9 percentages, and non-esterified fatty acids concentration, and it caused a decline in milk polyunsaturated fatty acids percentage. As well, dietary inclusion of corn silage significantly decreased plasma urea nitrogen content in goats (P<0.05). Furthermore, feeding corn silage led to a significant increase in antioxidant capacity of rumen liquor (P<0.05), plasma (P<0.01), and milk (P<0.01) of lactating goats. Of note, the dietary addition of corn silage caused no significant effects on microbial nitrogen and nitrogen balance in lactating goats. Feeding corn silage did not affect the ruminal total volatile fatty acids, acetic acid, propionic acid, and butyric acid at both periods before and after feeding. In general, results indicated that replacing dry forage with corn silage could consequently improve the antioxidant status in Mahabadi lactating goats.

Effects of endocannabinoids on feed intake, stress response and whole-body energy metabolism in dairy cows

Endocannabinoids, particularly anandamide (AEA) and 2-arachidonoylglycerol (2-AG), are instrumental in regulating energy homeostasis and stress response. However, little is known about the endocannabinoid system (ECS) in ruminants, although EC could improve dairy health and productivity, at least by increasing feed intake. In this study, we report if intraperitoneal (i.p.) AEA and 2-AG administration affects feed intake, whole-body macronutrient metabolism, isolation and restraint stress, and whether diet composition modulates circulating endocannabinoid concentrations in cows. Twenty Simmental cows in late lactation were fed a grass silage and a corn silage based diet. On each diet, cows received daily i.p. injections with either AEA (5 µg/kg; n = 7), 2-AG (2.5 µg/kg; n = 6) or saline (n = 7) for 8 days. Endocannabinoid administration for 5 days under free-ranging (non-stressed) conditions had no effect on feed intake or energy balance, but attenuated the stress-induced suppression of feed intake when housing changed to individual tie-stalls without social or tactile interaction. Endocannabinoids increased whole-body carbohydrate oxidation, reduced fat oxidation, and affected plasma non-esterified fatty acid concentrations and fatty acid contents of total lipids. There was no effect of endocannabinoids on plasma triglyceride concentrations or hepatic lipogenesis. Plasma AEA concentrations were not affected by diet, however, plasma 2-AG concentrations tended to be lower on the corn silage based diet. In conclusion, endocannabinoids attenuate stress-induced hypophagia, increase short-term feed intake and whole-body carbohydrate oxidation and decrease whole-body fat oxidation in cows.