Suchergebnisse

Two experiments were performed to study the effects of the citrus flavonoids extract Bioflavex® (Interquim S.A., FerrerHealthTech, Sant Cugat, Barcelona, Spain; BF) or its components on the rumen fermentation of a high concentrate diet. In an in vivo experiment, 8 Friesian steers (398 ± 12.2 kg body weight) fitted with a rumen cannula were given a basal concentrate (CTR) or CTR supplemented with BF (450 mg/kg dry matter, DM) in a 2 x 4 cross-over design. No differences were observed in performance parameters of BF and CTR steers. Diet BF increased pH values and the molar proportion of propionate. On the other hand, it reduced lactate concentration as a result of an increase in the relative abundance of lactate-consuming microorganism Selenomomas ruminantium (P < 0.01) and Megaesphaera elsdenii (P = 0.06). In an in vitro experiment, the effect of BF and its pure flavonoid components added to the incubation medium was studied separately. Bioflavex® and its main components naringine (NG), neohesperidine (NH) and poncirine (PC) were added to the incubation medium at 500 µg/g DM, with the unsupplemented substrate also included as a control (CTR). After 12 h of incubation, flavonoids mixture and NH and PC reduced (P < 0.01) the volume of gas produced and the molar proportion of acetate (P < 0.01), increased that of propionate (P < 0.01). Poncirine reduced the relative quantification of Streptococcus bovis, whereas NH and BF increased the relative quantification of M. elsdenii in relation to CTR (P < 0.01). Bioflavex® supplementation in steers in feedlot was effective in preventing collapses in pH and enhanced rumen fermentation efficiency through modifying the activity of lactate-consuming bacteria and a greater molar proportion of propionate and a reduction of that of acetate, suggesting its positive role in modulating the activity of rumen microbiota. ; This research was financed by Interquim SA (FerrerHealthTech), Sant Cugat, Barcelona. A. R. Seradj was a recipient of a grant from the Government of Catalonia (FI-DGR 2011) and A. Gimeno received a FPI grant from the MICINN (Spanish Government).

Methane is the main greenhouse gas contributor to global warming in the livestock sector; it is generated by anaerobic fermentation in the different sections of the gut, and differs significantly among species. Methane is only produced by a certain type of microorganisms called methanogens. The species composition of methanogenic archaea population is largely affected by the diet, geographical location, host and the section of the gut. Consequently, methane production, either measured as total grams emitted per day or per body weight mass, differs greatly between animal species. The main difference between methanogenic activity in different gut sections and animal species is the substrate fermented and the metabolic pathway to complete anaerobic fermentation of plant material. The three main substrates used by methanogens are CO2, acetate and compounds containing methyl groups. The three dominant orders of methanogens in gut environments are Methanomicrobiales, Methanobacteriales and Methanosarcinales. They normally are present in low numbers (below 3 % of total microbiome). This review will describe the main metabolic pathways and methanogens involved in CH4 production in the gut of different host animal, species, as well as discuss general trends that influence such emissions, such as geographical distribution, feed composition, section of the gut, host age and diurnal/season variation. Finally, the review will describe animal species (large and small domestic ruminants, wild ruminants, camelids, pigs, rabbits, horses, macropods, termites and humans) specificities in the methanogens diversity and their effects on methane emission. ; This work was supported by FEDER/Ministerio de Ciencia, Innovación yUniversidades - Agencia Estatal de Investigación (grant number AGL2017-89289) and European Union's H2020 program under National Institutes ofHealth (Feed-a-Gene, grant number 633531).

Characterization of intestinal microbiota is of great interest due to its relevant impact on growth, feed efficiency and pig carcass quality. Microbial composition shifts along the gut, but it also depends on the host (i.e., age, genetic background), diet composition and environmental conditions. To simultaneously study the effects of producing type (PT), production phase (PP) and dietary crude protein (CP) content on microbial populations, 20 Duroc pigs and 16 crossbred pigs (F2), belonging to growing and fattening phases, were used. Half of the pigs of each PT were fed a moderate CP restriction (2%). After sacrifice, contents of ileum, cecum and distal colon were collected for sequencing procedure. Fattening pigs presented higher microbial richness than growing pigs because of higher maturity and stability of the community. The F2 pigs showed higher bacterial alpha diversity and microbial network complexity (cecum and colon), especially in the fattening phase, while Duroc pigs tended to have higher Firmicutes/Bacteroidetes ratio in cecum segment. Lactobacillus was the predominant genus, and along with Streptococcus and Clostridium, their relative abundance decreased throughout the intestine. Although low CP diet did not alter the microbial diversity, it increased interaction network complexity. These results have revealed that the moderate CP restriction had lower impact on intestinal microbiota than PP and PT of pigs. ; This research was a part of the Feed-a-Gene project and received funding from the European Union's H2020 program under National Institutes of Health (grant number 633531), as well as Spanish National funding by the Spanish Ministry of Economy and Competitiveness (AGL2017-89289- R). L. Sarri is the recipient of a research training grant from the Generalitat de Catalunya-European Social Funds (2019 FI_B 00416).

Context. Improving feed efficiency in livestock production is of great importance to reduce feeding costs. Aims. To examine the relationship between ruminal microbiota and variation in feed efficiency in beef cattle fed concentrate-based diets. Methods. Residual feed intake of 389 fattening bulls, supplied with corn-based concentrate and forage ad libitum, was used to estimate animals' feed efficiency. Faeces and ruminal fluid samples, from 48 bulls chosen at random, were collected to estimate their forage intake and to determine their apparent digestibility, ruminal fermentation and microbiota. Those animals with extreme values of feed efficiency (high-efficiency (HE, n = 12) and low-efficiency (LE, n = 13)) were subjected to further comparisons. Alpha biodiversity was calculated on the basis of the normalised sequence data. Beta diversity was approached through performing a canonical correspondence analysis based on log-transformed sequence data. Genera differential abundance was tested with an ANOVA-like differential expression analysis and genera interactions were determined applying the sparse correlations for compositional data technique. Keyresults.No differences in dry matter intake were found between the two categories of feed efficiency (P = 0.699); however, HE animals had higher apparent digestibility of dry matter (P = 0.002), organic matter (P = 0.003) and crude protein (P = 0.043). The concentration of volatile fatty acids was unaffected by feed efficiency (P = 0.676) but butyrate proportion increased with time in LE animals (P = 0.047). Ruminal microbiota was different between HE and LE animals (P = 0.022); both a biodiversity and genera network connectance increased with time in LE bulls (P = 0.005 for Shannon index and P = 0.020 for Simpson index), which suggests that LE animals hosted a more robust ruminal microbiota. Certain genera usually related to high energy loss through methane production were found to establish more connections with other genera in LE animals' rumen than in HE ones. Microbiota function capability suggested that methane metabolism was decreased in HE finishing bulls. Conclusions. Rumen microbiota was associated with feed efficiency phenotypes in fattening bulls fed concentrate-based diets. Implications. The possible trade-off between feed efficiency and robustness of ruminal microbiota should be taken into account for the optimisation of cattle production, especially in systems with intrinsic characteristics that may constitute a disturbance to rumen microbial community. ; This study is a part of GenTORE project and received funding from the European Union H2020 program under grant agreement nº 727213 and Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (RTA-14-038-C02). S. Costa-Roura is recipient of a research training grant from Spanish Ministry of Science and Innovation (FPU 2016/03761). A. R. Seradj contract is financed by GenTORE project.

In order to reduce dietary nitrogen and achieve an efficient protein deposition as well as decrease N wastage, we challenged the nutrient utilization efficiency of two different producing types in front of a dietary crude protein (CP) restriction and studied the role of the microbiota in such an adaptation process. Therefore, 32 pure castrated male Duroc (DU) and 32 entire male hybrid (F2) piglets were raised in a three-phase feeding regime. At each phase, two iso caloric diets differing in CP content, also known as normal protein (NP) and low protein (LP), were fed to the animals. LP diets had a fixed restriction (2%) in CP content in regards to NP ones throughout the phases of the experiment. At the end of third phase, fecal samples were collected for microbiota analysis purposes and greenhouse gases emissions, together with ammonia, were tested. No changes were found in average daily feed intake (ADFI) of animals of two producing types (Duroc vs. F2) or those consumed different experimental diets (NP vs. LP) throughout the course of study. However, at the end of each experimental phase the average body weight (BW) of hybrid animals were higher compared to Duroc pigs, whereas a reverse trend was observed for average daily gain (ADG), where Duroc pigs showed greater values with respect to hybrid ones. Despite, greater CH4 and ammonia emissions in Duroc pigs with respect to F2, no significant differences were found in contaminant gases emissions between diets. Moreover, LP diets did not alter the microbial community structure, in terms of diversity, although some genera were affected by the dietary challenge. Results suggest that the impact of reducing 2% of CP content was limited for reduction in contaminant gases emissions and highlight the hypothesis that moderate change in the dietary protein levels can be overcome by long-term adaptation of the gut microbiota. Overall, the influence of the producing type on performance and digestive microbiota composition was more pronounced than the dietary effect. However, both producing types responded differently to CP restriction. The use of fecal microbiota as biomarker for predicting feed efficiency has a great potential that should be completed with robust predictive models to achieve consistent and valid results. ; This work was supported by FEDER/Ministerio de Ciencia, Innovación y Universidades—Agencia Estatal de Investigación (grant number AGL 2017-89289) and European Union's H2020 program under National Institutes of Health (Feed-a-Gene, grant number 633531). Laura Sarri is recipient of a research training grant from the Generalitat de Catalunya-European Social Funds (FI-DGR 2019).

Twelve lactating sows were used to evaluate the effects of reducing dietary crude protein (CP) (14% vs. 12%) and increasing neutral detergent fibre (NDF) levels (18% vs. 22%) on litter performance, total tract apparent digestibility and manure composition in a 4 9 4 latin square arrangement during a 36-day lactation period. Diets were isoenergetic (2.9 Mcal ME/kg) and had similar total lysine content (0.9%). In addition, a second aim was to compare a reference external marker method (Cr2O3) with an internal feed marker [acid-insoluble ash (AIA)] for the calculation of apparent total tract digestibility of nutrients in lactating sows. The reduction of dietary CP level in lactating sows had no effect on either live-weight or backfat thickness or apparent total tract digestibility of nutrients. However, the piglets' average daily gain (ADG) was reduced in low dietary CP diets, which suggests that sows reduced milk production due to an underestimation of certain essential amino acid requirements (e.g. valine). The increase of dietary NDF level did not affect sow and litter performance. Nevertheless, the total tract apparent digestibility of organic matter, CP and carbohydrates was reduced, and ether extract digestion was increased in high NDF compared to normal NDF diets equally balanced for ME and lysine content. The coefficients of total tract apparent digestibility of nutrients in lactating sows were greater when using AIA compared to Cr2O3 marker, regardless of dietary CP or NDF level, but their coefficients of variation were lower in the former than in the latter. In lactating sows, a trade-off between litter performance and nutrient digestion is established when reducing dietary CP or increasing NDF levels while maintaining similar lysine content through synthetic amino acids and balancing metabolizable energy through dietary fat sources. ; This work was supported by the Ministry of Economy and Competitiveness of Spain and the European Union Regional Development Funds (AGL2010- 20820). The authors wish to thank the staff of the Centre d'Estudis Porcins (CEP Diputaci o de Lleida) and Indira Medina for their technical assistance during sample collection. In addition, the collaboration of Lorenzo Fraile for pharmacological oestrus synchronization of gilts is acknowledged

Besides the beneficial agronomic properties such as drought tolerance and high biomass production, the high crude protein content of Moringa oleifera (Moringa) makes it comparable to the other high quality forages. This study aimed to evaluate whether Moringa can be an appropriate substitute for alfalfa as a ruminant feed. The study consisted of 4 treatments, namely Moringa leaves harvested at 30 (M30), 40 (M40), and 50 (M50) days after pruning, and alfalfa (Medicago sativa) hay as a control. Simultaneously, their organic matter digestibilities and fermentation characteristics were analyzed by in vitro gas production technique and rumen dry matter and protein degradability kinetics were analyzed by using the nylon bags (in situ) procedure. The results of in vitro study revealed that the potential cumulative gas production for Moringa sample harvested at 30 days after pruning was higher than that of alfalfa while the rate of gas production and the concentrations of ammonia and volatile fatty acids (VFA) in Moringa were similar to alfalfa. Moringa harvested at different times had higher in vitro organic matter digestibility (IVOMD) and metabolizable energy (ME) content as compared with alfalfa. Despite the apparent higher soluble fraction (a) and the fractional degradation rate (c) in the Moringa samples of various ages than those for alfalfa, the differences were not significant. However, in situ potentially degradable fraction (b) for DM and CP of Moringa harvested at different ages were higher than those of alfalfa (P<0.05). The in vitro fermentation and in situ degradation parameters suggested high similarities in the kinetics of gas production (i.e. a, b, and c) and DM degradation pattern among the three different cutting ages of Moringa and nutritionally they were comparable to alfalfa. In conclusion, alfalfa could be replaced with Moringa leaves in diet of ruminant animal without any adverse effect. ; This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Ahmad Reza Seradj was a recipient of a research training grant from the Government of Catalonia (FIDGR 2011-Generalitat de Catalunya) and Henris Morazán was supported by a grant from the Ministry of Foreign Affairs and Cooperation of Spain (MAEC-AECID 2009-2011). The authors wish to thank Leonidas Morazán for his assistance.

Differences in producing performance and organoleptic meat characteristics among pig genotypes and/or producing types are widely known. These parameters are also subjected to the animal's development, feeding and management. Detailed knowledge of the effects of production phase (PP), pig producing type (PT), dietary protein availability and their interactions on nutrient digestibility, nitrogen balance and protein metabolism is essential information to improve precision feeding techniques. The experiment was a 2 (PP) × 2 (PT) × 2 (diet) factorial design conducted with 32 male pigs, 16 entire F2 pigs progeny of Pietrain sires and Duroc × Landrace dams, and 16 castrated purebred Durocs belonging to two production phases (growing: 29.5 ± 3.19 v. fattening: 88.6 ± 6.26 kg BW), and assigned to one of two dietary CP levels, either standard (SP: 17% in growing and 15% in fattening) or low (LP: 15% in growing and 13% in fattening). Viscera and muscle fractional protein synthesis rates (FSRs; %/day) were conducted through a single infusion of 15% L-[ring-2H5]-phenylalanine, with subsequent blood sampling from 12 to 40 min, and sample collection of liver, duodenum, biceps femoris and longissimus dorsi skeletal muscles after sacrifice. Fattening animals acquired a greater feed ingestion capacity, average daily gain (P < 0.01) and apparent ileal digestibility, whereas growing pigs showed higher FSRs in both viscera (duodenum and liver) and in longissimus dorsi. F2 pigs showed higher average daily gain, nitrogen retention rates and FSR in liver and longissimus dorsi (P < 0.01). Nevertheless, apparent ileal digestibility in all essential amino acids was lower in F2 compared with Duroc pigs (P < 0.05). Protein metabolism was barely influenced by dietary CP content, although animals fed LP registered the lowest apparent ileal digestibility for CP and also for most of the essential amino acids compared with SP-fed pigs. This information may reveal differences in amino acid requirements between both PTs, with Duroc pigs receiving excess of dietary amino acids ; This study was a part of the Feed-a-Gene project and receivedfunding from the European Union's H2020 program under NationalInstitutes of Health (grant number 633531), as well as SpanishNational funding by MINECO (AGL2017-89289-R). L. Sarri is recip-ient of a research training grant from the Generalitat de Catalunya-European Social Funds (2019 FI_B 00416).

Sixty-four cross bred 6 week-old intact male pigs (initial BW=13.8 ± 2.3 kg) were randomly distributed to 4 separated modules using a three-phase feeding program in which two dietary crude protein (CP) and total dietary fiber (TDF) levels were tested in a 2×2 factorial arrangement under a commercial-like production system. The room air was sampled and analyzed for NH3 and CH4 while the slurry pit air was sampled and analyzed for CH4 content during the early growing (phase I, 13.8-38.6 kg of body-weight), growing (phase II, 38.6-72.8 kg of body-weight) and finishing periods (phase III, 72.8-108.7 kg of body-weight); at the end of the finishing phase, 16 random pigs were sacrificed and cecum and colon contents were sampled to determine fermentation and microbial parameters. The pH and ammonium content increased with digesta transit being lower in cecum (6.0 and 69.7 mg/L) than in colon (6.3 and 156.3 mg/L) whereas the opposite trend was seen for total VFA and acetate (175.2mM and 62.6 mol/100 mol vs. 141.1mM and 57.2 mol/100 mol, respectively; P < 0.05). Low protein (LP) and high fiber (HF) diets showed a higher NH3 concentration in the colon but not in cecum samples. Dietary fiber also altered intestinal VFA concentration where animals fed Low fiber (LF) diet showed high VFA's concentrations and such effect was more pronounced in colon samples. Total NH3 (1.8, 4.8 and 8.5 g/day) and methane (2.5, 3.5 and 7.5 g/day for Phase I, II and III, respectively) emissions increased consistently with age (P < 0.05), dietary CP level increased NH3 volatilization (6.3 vs. 3.8 g/d for high protein (HP) and LP diets respectively; P < 0.01) and fiber tended to increase methane emission (5.0 vs. 4.0 for HF and LF diets, respectively P < 0.1). The methane production measured at slurry pit contributed significantly to total CH4 emission (3.26, 9.02 and 16.91% in the phases I, II and III respectively). Dietary CP increased total bacteria (TB; 9.7 vs. 9.5; P < 0.03) and total methanogenic archaea (TMA; 7.2 vs. 6.4; P < 0.01) abundances in the intestinal as well as the slurry (6.8 vs. 6.3 Log n° copy/ g fresh matter (FM); P < 0.01) samples ; This work is part of the Feed-a-Gene project and was supported by the European Union's H2020 program under National Institutesof Health [grant number 633531, 2016]. Authors would like to thank Dr. David Parker who generously gave his assistance andconstructive comments to the manuscript, his effort is sincerely appreciated.

Artificial slurry (4% dry matter) was prepared using fresh feces and urine obtained from four pregnant sows fed with commercial diet. Freeze-dried dairy cattle feces were used (external archaea) as co-inoculum (Co-i) and structural carbohydrates (CHO: apple pulp; sugar beet pulp; and wheat straw) as substrates. Bottles were incubated (39 +/- 1 degrees C for 56 days), and the gas production was measured (mbar) and converted to the volume. A sample of produced gas was taken and analyzed for methane concentration using a gas chromatography. Bottles were opened at days 0, 25, and 56 to determine total bacteria, total, and hydrogenotrophic methanogens archaea (HMA) concentrations using quantitative polymerase chain reaction and population biodiversity using denaturing gradient gel electrophoresis (DGGE). Incubation time reduced the titers of total bacteria and archaea (P0.05), whereas at 10% Co inoculation, titers decreased constantly. Most of the archaeal DGGE bands were observed in all samples, suggesting a common microbial population origin but Co-i supply altered the DGGE structure of archaea populations ; This work was supported by the Ministry of Economy and Competitiveness of Spain and the European Union Regional Development Funds (AGL2010-20820). Ahmad Reza Seradj is a recipient of grant from the Government of Catalunya (FI-DGR 2011) and Henris Morazan was a recipient of grant from MAEC-AECID 2009–2011.