Promote Animal Growth Research Articles

Strong adsorption of tetracycline on octahedral Cu2O nanocrystals exposed with {111} facets: Adsorption behavior and mechanism insight

The extensive use of tetracycline (TC) as veterinary therapeutics and animal growth promoters has caused human health problems. Some adsorbents have been developed to remove TC, but the adsorption capacity is still unsatisfactory. Here, we synthesized octahedral cuprous oxide nanocrystals (oct-Cu2O NCs) by a hydrothermal method at room temperature. Surprisingly, the maximum adsorption capacity of oct-Cu2O NCs reached an astonishing amount of 1112.6 mg/g. Adsorption kinetics and isotherm experiments for TC removal were carried out to evaluate its potential as an adsorbent. The key factors like pH and solution ions as well as the mechanism of TC adsorption on oct-Cu2O NCs were also studied. The main adsorption process may be that the hydroxyl group (-OH) on the {111} facets surface of oct-Cu2O NCs is replaced by the amino group (-NH2) of TC. The high adsorption capacity is generated by the abundant Cu atoms with dangling bonds on the {111} facets surface and the strong chemical coordination between the -NH2 of TC and Cu(I). This work provides an alternative with a promising application prospect for the treatment of TC in water.

Probiotic Attributes of Lactobacillus fermentum NKN51 Isolated from Yak Cottage Cheese and the Impact of Its Feeding on Growth, Immunity, Caecal Microbiology and Jejunal Histology in the Starter Phase of Broiler Birds

Background: The discovery of antibiotics was a great success in control of the pathogenic infections in living beings. In addition, it also played a significant role in upliftment of the meat industry with their use as the growth promoters in the food animals including poultry. However, massive and incorrect use of antibiotics has resulted in the adverse outcome of antibiotic resistance over the years. In order to limit the antibiotic resistance at industry level itself, exploration of the possible alternatives such as probiotics is the need of the hour to replace the antibiotics in poultry industry without compromising the productivity. Hence, the present study was conducted to explore the effects of a novel probiotic bacterium, Lactobacillus fermentum NKN51 on the production performance of the broilers with an aim to replace the antibiotics in poultry production. Methods: In the present study, a total of 128 broiler birds were grouped randomly into four treatment groups which were fed basal diet (BD) along with the different levels of L. fermentum NKN51,viz.,T1 (BD+107cfu/gm), T2(BD+106cfu/gm), T3 (BD+105cfu/gm) and T4 or control (BD only) for a period of 28 days so as to observe the effect of Lactobacillus fermentum NKN51 in the starter phase of the broiler birds in terms of growth, immunity, gut health and physiology. Result: The result revealed that the group of broiler birds supplemented with Lactobacillus fermentum NKN51 at the level of 107cfu/gm of basal feed had significantly better growth performance, cell mediated and humoral immunity, gut health and jejunal histology in terms of villus height, VH:CD ratio and intestinal absorption capacity. Thus, Lactobacillus fermentum NKN51 was found as an ideal probiotic supplement exhibiting better potential in enhancing the efficiency of broiler birds in terms of improved productivity.

Effects of Bacillus amyloliquefaciens and Bacillus pumilus on Rumen and Intestine Morphology and Microbiota in Weanling Jintang Black Goat.

Simple SummarySelecting Bacillus amyloliquefaciens and Bacillus pumilus in the present work, antibiotic substitutes were found for weaned black goat health and growth. This study indicated that Bacillus amyloliquefaciens fsznc-06 and Bacillus pumilus fsznc-09 improved the development of rumen and small intestine in weanling Jintang black goats. They also regulated microbial communities by increasing the richness of beneficial bacteria, but decreasing that of pathogenic bacteria in rumen and caecum for nutrient metabolism and promoting healthy conditions.The importance of Bacillus as feed additives in animals’ production is well recognized. Bacillus amyloliquefaciens and Bacillus pumilus are involved in promoting animal growth performance and immunological indicators. However, their precise roles in the modulation of microbiota and immune response in goat rumen and intestines have not been investigated. The aim of the current work was to evaluate the impacts of Bacillus amyloliquefaciens fsznc-06 and Bacillus pumilus fsznc-09 in the development of rumen and small intestinal and microbial communities in rumen and caecum of weanling Jintang black goats. Morphological alterations of rumen and small intestine (duodenum, jejunum, and ileum) were evaluated by histochemical staining, and ruminal contents and cecal feces were analyzed by 16S rRNA sequencing in an Illumina NovaSeq platform. Morphological analysis showed that feeding weanling goats with Bacillus amyloliquefaciens fsznc-06 or Bacillus pumilus fsznc-09 enhanced ruminal papilla and small intestinal villus growth. In addition, 16S rRNA sequencing analysis indicated that microbial richness and diversity (Shannon, Simpson, Chao1, and ACE) and the relative richness of multiple or potential beneficial bacteria were higher in weaned black goats fed on Bacillus amyloliquefaciens fsznc-06 or Bacillus pumilus fsznc-09, but that of multiple or potentially pathogenic bacteria were lower, as compared with the control group. Tax4Fun analysis predicting the functional profiling of microbial communities showed that microbial communities in rumen or caecum were highly influential on metabolism and organism systems after feeding weanling goats with Bacillus amyloliquefaciens fsznc-06 or Bacillus pumilus fsznc-09. It was suggested that Bacillus amyloliquefaciens fsznc-06 and Bacillus pumilus fsznc-09 might be an auspicious antibiotic alternative to improve black goat growth and health by changing rumen and gut microbiota positively.

A Novel Nanobody Directed against Ovine Myostatin to Enhance Muscle Growth in Mouse.

Simple SummaryMyostatin (MSTN) is a negative regulator of myogenesis, and various strategies have been used to improve livestock production by inhibiting MSTN. In this study, we developed a single-variable domain of the heavy chain antibody-recombinant MSTN nanobody (RMN) against MSTN. The selected RMN was expressed, purified, and assessed for its cytotoxicity, affinity, specificity, and the ability to inhibit MSTN. The results demonstrated that RMN could specifically detect and bind MSTN, further inhibit myostatin activity, as well as enhance muscle growth in mice.Myostatin (MSTN) is a member of the transforming growth factor beta superfamily and is a negative regulator of myogenesis. It has been shown to function by controlling the proliferation of myoblasts. MSTN inhibition is considered as a promising treatment for promoting animal growth in livestock. Nanobodies, a special antibody discovered in camel, have arisen as an alternative to conventional antibodies and have shown great potential when used as tools in different biotechnology fields, such as diagnostics and therapy. In this study, we examined the effect of MSTN inhibition by RMN on the muscle growth of mice. The results showed that RMN could specifically detect and bind MSTN, as well as inhibit MSTN activity. A significant increase in skeletal muscle mass was observed after intramuscular injection of RMN into mice. Enhanced muscle growth occurred because of myofiber hypertrophy. These results offer a promising approach to enhance muscle growth that warrants further investigation in domestic animals.

Effects of dietary ferulic acid on growth performance, carcass traits and meat quality of heifers

Ferulic acid is a natural occurring compound with antioxidant and antimicrobial bioactive properties, and recently was proposed as a new alternative growth promoter in meat-producing animals without changing meat quality parameters. The present study aimed to evaluate the impact of two doses of ferulic acid (FA) on the feedlot performance, carcass traits, and physicochemical and sensory characteristics of meat quality in commercial heifers. Ninety heifers (3/4 Bos taurus; n = 270; body weight = 480 ± 10 kg) were randomly assigned to one of the following treatments (30 days): Control, fed with a basal diet; FA250 or FA500 offered the same diet further supplemented with FA at 250 or 500 mg kg-1 feed, respectively. Feedlot performance, carcass traits, and physicochemical and meat sensory characteristics were evaluated. FA supplementation increased average daily gain (ADG) by 21%, hot carcass weight by 1.8% and cold carcass weight by 1.6% with respect to the control (P < 0.05). FA500 treatment caused a decrease (P < 0.05) in some carcass traits. However, carcass characteristics of economic importance, such as cold carcass dressing and LT muscle area, were improved by FA250 supplementation (P < 0.05), causing a possible growth promoter effect. Physicochemical and sensory parameters of meat were not altered by FA supplementation (P > 0.05). Ferulic acid has the potential for use as a growth promoter additive in finishing heifers without negatively affecting the meat quality, as occurs with some synthetic growth promotants compounds used in animal production. © 2020 Society of Chemical Industry.

Determination of veterinary drug residues in food of animal origin: Sample preparation methods and analytical techniques

Veterinary drugs are widely used in animal husbandry to prevent and treat animal diseases, to promote animal growth, and to improve the conversion rate of feed. However, the use of veterinary drugs in food-producing animals may leave residues of the parent compounds, and/or their metabolites in food products resulting in harmful effects to humans. To ensure food safety, sensitive and effective analytical methods have been developing rapidly. So it is necessary to make a systematic summary of detection methods of veterinary drug residues. Sample preparation methods and analytical techniques are the two main parts of analyzing veterinary drug residues which were described in detail. Sample preparation methods, such as solid-phase extraction, liquid–liquid extraction, immunoaffinity chromatography, and QuEChERS, were summarized by the specific examples. The three types of methods, microbial, immunological, and physicochemical methods, for screening or determination were described, including microbial inhibition, enzyme-linked immunosorbent assay, colloidal gold immunoassay, fluorescence polarization immunoassay, biosensor technology, application of quantum dots, capillary electrophoresis, liquid chromatography, and liquid chromatography-mass spectrometry. In addition, the advantages and shortcomings of methods were also described. The challenges and prospects were discussed for the analysis of veterinary drug residues in animal-derived foods.

Isolation of antibiotic-resistant bacteria in biogas digestate and their susceptibility to antibiotics

Antibiotics are widely used to prevent and treat diseases and promote animal growth in the livestock industry, and therefore antibiotic residues can end up in biogas digestate from processes treating animal manure (AM) and food waste (FW). These digestates represent a potential source of spread of antimicrobial resistance (AMR) when used as fertilisers. This study evaluated AMR risks associated with biogas digestates from two processes, using AM and FW as substrate, by isolation and identification of antibiotic-resistant bacteria (ARB) and testing their susceptibility to different antibiotics. ARB from the digestates were isolated by selective plating. The antibiotic susceptibility profile of isolates was determined using ampicillin, ceftazidime, meropenem, vancomycin, ciprofloxacin, rifampicin, chloramphenicol, clindamycin, erythromycin, tetracycline, gentamicin or sulfamethoxazole/trimethoprim, representing different antibiotic classes with differing mechanisms of action. In total, 30 different bacterial species belonging to seven genera were isolated and classified. Bacillus and closely related genera, including Paenibacillus, Lysinibacillus and Brevibacillus, were the dominant ARB in both digestates. Most of the ARB strains isolated were non-pathogenic and some were even known to be beneficial to plant growth. However, some were potentially pathogenic, such as an isolate identified as Bacillus cereus. Many of the isolated species showed multi resistance and the AM digestate and FW digestate both contain bacterial species resistant to all antibiotics tested here, except gentamicin. A higher level of resistance was displayed by the FW isolates, which may indicate higher antibiotic pressure in FW compared with AM digestate. Overall, the results indicate a risk of AMR spread when these digestates are used as fertiliser. However, most of the ARB identified are species commonly found in soil, where AMR in many cases is abundant already, so the contribution of digestate-based fertiliser to the spread of AMR may still be very limited.

Emerging nanosensing technologies for the detection of β-agonists.

Illegal usage of β-agonists as the animal growth promoters can lead to multiple harmful impacts to public health, thus detection of β-agonists at trace level in complex sample matrixes is of great importance. In recent years, emergence of advanced nanomaterials greatly facilitates the advancement of sensors in terms of sensitivity, specificity and robustness. Plenty of nanoparticles-based sensors have been developed for β-agonists determination. In this review, we comprehensively summarized the construction of emerging nanoparticles-based sensors (including colorimetric sensors, fluorescent sensors, chemiluminescent sensors, electrochemical sensors, electrochemiluminescent sensors, surface enhanced Raman scattering sensors, surface plasmon resonance sensors, quartz crystal microbalance sensors, etc.), and nanomaterial-based enzyme-linked immunosorbent assay (nano-ELISA). Impressively, the applications of nanoparticles-based sensors and nano-ELISAs in the detection of β-agonists have also been summarized and discussed. In the end, future opportunities and challenges in the design construction of nanoparticles (NPs)-based sensors and their applications in β-agonist assay are tentatively proposed.

Changes in colistin resistance and mcr-1 abundance in Escherichia coli of animal and human origins following the ban of colistin-positive additives in China: an epidemiological comparative study

Following the discovery and emergence of the plasmid-mediated colistin resistance gene, mcr-1, the Chinese government formally banned colistin as an animal growth promoter on April 30, 2017. Herein, we report patterns in colistin resistance and mcr-1 abundance in Escherichia coli from animals and humans between 2015 and 2019, to evaluate the effects of the colistin withdrawal. We did an epidemiology comparative study to investigate: annual production and sales of colistin in agriculture across mainland China according to data from the China Veterinary Drug Association from 2015 to 2018; the prevalence of colistin-resistant E coli (CREC) in pigs and chickens in 23 Chinese provinces and municipalities as reported in the China Surveillance on Antimicrobial Resistance of Animal Origin database from Jan 1, 2015, to Dec 31, 2016, and Jan 1, 2017, to Dec 31, 2018; the presence of residual colistin and mcr-1 in faeces from 118 animal farms (60 pig, 29 chicken, and 29 cattle) across four provinces over July 1, 2017, to August 31, 2017, and July 1, 2018 to August 31, 2018; the prevalence of mcr-1-positive E coli (MCRPEC) carriage in healthy individuals attending routine hospital examinations across 24 provinces and municipalities from June 1 to July 30, 2019, comparing with equivalent 2016 data (June 1 to September 30) from our previous study in the same hospitals; and the patterns in CREC prevalence among hospital E coli infections across 26 provinces and municipalities from Jan 1, 2015, to Dec 31, 2016, and Jan 1, 2018, to Dec 31, 2019, reported on the China Antimicrobial Surveillance Network. After the ban on colistin as a growth promoter, marked reductions were observed in the production (27 170 tonnes in 2015 vs 2497 tonnes in 2018) and sale (US$71·5 million in 2015 vs US$8·0 million in 2018) of colistin sulfate premix. Across 118 farms in four provinces, mean colistin residue concentration was 191·1 μg/kg (SD 934·1) in 2017 versus 7·5 μg/kg (50·0) in 2018 (p<0·0001), and the median relative abundance of mcr-1 per 16S RNA was 0·0009 [IQR 0·0001-0·0059] in 2017 versus 0·0002 [0·0000-0·0020] in 2018 (p=0·0001). Across 23 provinces and municipalities, CREC was identified in pig faeces in 1153 (34·0%) of 3396 samples in 2015-16 versus 142 (5·1%) of 2781 in 2017-18 (p<0·0001); and in chickens in 474 (18·1%) of 2614 samples in 2015-16 versus 143 (5·0%) of 2887 in 2017-18 (p<0·0001). In hospitals across 24 provincial capital cities and municipalities, human carriage of MCRPEC was identified in 644 (14·3%) of 4498 samples in 2016 versus 357 (6·3%) of 5657 in 2019 (p<0·0001). Clinical CREC infections in 26 provinces and municipalities comprised 1059 (1·7%) of 62 737 E coli infections in 2015-16 versus 794 (1·3%) of 59 385 in 2018-19 (p<0·0001). The colistin withdrawal policy and the decreasing use of colistin in agriculture have had a significant effect on reducing colistin resistance in both animals and humans in China. However, continuous colistin monitoring is essential, in particular to act as an early warning system for colistin stewardship in Chinese hospitals. National Key Research and Development Program of China, National Natural Science Foundation of China, and UK Medical Research Council.

PHYSIOLOGICAL AND ENVIRONMENTAL MONITORING OF TECHNOGENIC XENOBIOTICS IN THE FOOD-ANIMAL-PRODUCTION SYSTEM

One of the main reasons that significantly affect the functional state of the organism, animal and human health, scientists and practitioners consider the environmental state of the environment. This is primarily due to the content of toxicants, in particular heavy metals in feed grown in areas of man-made pollution, the feeding of which leads to impaired metabolism in the animal body. Certain heavy metals (Pb, Cd, Hg, As, etc.) are highly toxic and can affect the body even in very small quantities. Therefore, monitoring the toxic elements in the soil-plant-feed-animal-production-human-chain trophic chain is considered a priority area in research, under conditions of man-made loading. The works of a number of leading scientists, in particular R. Y. Kravtsiv, O. I. Razputny, I. V. Kalinin, Yu. I. Savchenko, R. Fedoruk, indicate that the ability to the accumulation of toxic elements by organisms is determined not only by the geochemistry of the environment, but also by their biological nature and the biogeochemical chain through which the connection between organisms and the environment (soil-plant-animal-human). Unfavorable ecological situation in some regions is caused by violation of requirements for chemical fertilizers, plant treatment with pesticides (herbicides, pesticides, etc.), which is especially characteristic nowadays, when large agro-industrial structures (holdings, concerns, etc.) for the cultivation of intensive crops.&#x0D; The mentioned reasons include animal and poultry growth promoters, certain groups of medicines, uncontrolled industrial emissions, man-made accidents, pollution of the environment by motor vehicle emissions, etc. As a result, the compounds of Plumbum, Cadmium, Hydrargyrum, Strontium and other heavy metals also enter the atmosphere. And what is characteristic (according to literature sources) is that some of them, together with atmospheric moisture, form even more toxic compounds, which in the form of rain fall on farmland and ponds, from where they enter plants and organisms of animals and food, in particular milk and meat. That is why it is necessary to carry out physiological and environmental monitoring, respectively, and control of the migration of harmful elements in the environment, in particular, their receipt and concentration in soils, plants of food groups, feeds, animals and food. In view of this, it is especially important to improve the diets of animals fed under conditions of techno-genic loading using sorbents and their biologically active additives. Such adsorbents R. Y. Kravtsіv and coauthors, O. O. Kalinin include zeolites that have adsorbing, ion exchange, catalytic and other properties, although their use should be carried out taking into account agro-environmental conditions, as well as the forms and properties of xenobiotics, which requires research with scientific and practical substantiation.

Phenomic and genomic approaches to studying the inhibition of multiresistant Salmonella enterica by microcin J25.

In livestock production, antibiotics are used to promote animal growth, control infections and thereby increase profitability. This practice has led to the emergence of multiresistant bacteria such as Salmonella, of which some serovars are disseminated in the environment. The objective of this study is to evaluate microcin J25 as an inhibitor of Salmonella enterica serovars of various origins including human, livestock and food. Among the 116 isolates tested, 37 (31.8%) were found resistant to at least one antibiotic, and 28 were multiresistant with 19 expressing the penta-resistant phenotype ACSSuT. Microcin J25 inhibited all isolates, with minimal inhibitory concentration values ranging from 0.06 μg/ml (28.4 nM) to 400 μg/ml (189 μM). Interestingly, no cross-resistance was found between microcin J25 and antibiotics. Multiple sequence alignments of genes encoding for the different proteins involved in the recognition and transport of microcin J25 showed that only ferric-hydroxamate uptake is an essential determinant for susceptibility of S. enterica to microcin J25. Examination of Salmonella strains exposed to microcin J25 by transmission electronic microscopy showed for the first-time involvement of a pore formation mechanism. Microcin J25 was a strong inhibitor of several multiresistant isolates of Salmonella and may have a great potential as an alternative to antibiotics.

Influence of Lactobacillus casei WB 315 and crude fish oil (CFO) on growth performance, EPA, DHA, HDL, LDL, cholesterol of meat broiler chickens

Use of antibiotics as growth promoters in animal feeds has been restricted due to the residues in poultry products such as egg and meat, furthermore to the antibiotic resistant of pathogenic bacteria. The prohibition of their use opens the opportunity for the use of non-antibiotic feed additives such as probiotics. The objectives of this study were to investigate the effect of the addition of Lactobacillus casei WB 315 and crude fish oil (CFO) to diets on growth performance, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), low density lipoproteins (LDL), high density lipoprotein (HDL), and cholesterol levesl of broiler chickens. In this research, one-day old male broiler chicks were used and divided equally into four groups, namely a basal diet without L. casei WB 315 and without CFO (P0), basal diet supplemented with 0.5% L. casei WB 315 of total broiler basal feed (1.2 × 109 cfu/ml) and without CFO (P1), basal diet supplemented without L. casei WB 315 and 1% CFO of total broiler basal feed (P2), and basal diet supplemented with 0.5% L. casei WB 315 of total broiler basal feed (1.2 × 109 cfu/ml) and 1% CFO of total broiler basal feed (P3) for 35 days. The results of addition 0.5% Lactobacillus casei WB 315 (1.2 × 109 cfu/ml) and 1% CFO of total broiler basal feed after 35 days showed significant difference among treatment in feed efficiency (p<0.05), feed conversion ratio (p<0.05), feed consumption (p<0.05), EPA (p<0.05), DHA (p<0.05), increase HDL (p<0.05), reduced the LDL (p<0.05), and reduce cholesterol (p<0.05) in meat broiler chicken. It is concluded that the addition of L. casei WB 315 and crude fish oil (CFO) could significant improve the growth performance (feed efficiency, feed conversion ratio, feed consumption) and could significantly improve EPA, DHA and increase HDL and decrease LDL in meat poultry product.

Monensin biodegradation pathway and role of epoxide hydrolase in Stenotrophomonas maltophilia DM‐2

AbstractBACKGROUNDMonensin is widely used in livestock and poultry production to promote animal growth and control coccidiosis. Most monensin is excreted as unchanged parent compounds via feces. However，monensin is very stable and difficult to degrade in the environment, and is potentially risky for the health of wildlife and humans. To date, the biodegradation process of monensin by bacteria and its mechanism is unclear. In this study, we found that a Stenotrophomonas maltophilia DM‐2 strain isolated from chicken manure could effectively degrade monensin.RESULTThe optimum temperature and pH for DM‐2 to degrade monensin were 40 °C and pH 7.0. A potential degradation pathway of monensin was proposed based on the identification and characterization of two new monensin metabolic intermediates by liquid chromatography quadrupole time‐of‐flight mass spectroscopy. In addition, an inducible monensin‐degrading activity was present in DM‐2. A soluble epoxide hydrolysis (sEH) gene highly expressed in the DM‐2 on day 3 and 6 under monensin stress, which was not observed in the DM‐2 without monensin stress. When a specific inhibitor TPPU (1‐(1‐propanoylpiperidin‐4‐yl)‐3‐[4‐(trifluoromethoxy)phenyl]urea) of sEH was added into the cell‐free extract, the degradation of monensin was inhibited.CONCLUSIONStrain DM‐2 can biodegrade monensin by soluble epoxy hydrolase and produce two new intermediates. To our knowledge, this is the first report of the degradation of monensin by Stenotrophomonas strains. The novel metabolic pathways of monensin which we found may provide new insight into the environmental fate of monensin. © 2020 Society of Chemical Industry

Evaluation of bile salt hydrolase inhibitor efficacy for modulating host bile profile and physiology using a chicken model system

Gut microbial enzymes, bile salt hydrolases (BSHs) are the gateway enzymes for bile acid (BA) modification in the gut. This activity is a promising target for developing innovative non-antibiotic growth promoters to enhance animal production and health. Compelling evidence has shown that inhibition of BSH activity should enhance weight gain by altering the BA pool, host signalling and lipid metabolism. We recently identified a panel of promising BSH inhibitors. Here, we address the potential of them as alternative, effective, non-antibiotic feed additives, for commercial application, to promote animal growth using a chicken model. In this study, the in vivo efficacy of three BSH inhibitors (caffeic acid phenethylester, riboflavin, carnosic acid) were evaluated. 7-day old chicks (10 birds/group) were either untreated or they received one of the specific BSH inhibitors (25 mg/kg body weight) via oral gavage for 17 days. The chicks in treatment groups consistently displayed higher body weight gain than the untreated chicks. Metabolomic analysis demonstrated that BSH inhibitor treatment led to significant changes in both circulating and intestinal BA signatures in support of blunted intestinal BSH activity. Consistent with this finding, liver and intestinal tissue RNA-Seq analysis showed that carnosic acid treatment significantly altered expression of genes involved in lipid and bile acid metabolism. Taken together, this study validates microbial BSH activity inhibition as an alternative target and strategy to antibiotic treatment for animal growth promotion.

Antimicrobial Resistance and Food Animals: Influence of Livestock Environment on the Emergence and Dissemination of Antimicrobial Resistance.

The emergence and dissemination of antimicrobial resistance among human, animal and zoonotic pathogens pose an enormous threat to human health worldwide. The use of antibiotics in human and veterinary medicine, and especially the use of large quantities of antibiotics in livestock for the purpose of growth promotion of food animals is believed to be contributing to the modern trend of the emergence and spread of bacteria with antibiotic resistant traits. To better control the emergence and spread of antimicrobial resistance several countries from Western Europe implemented a ban for antibiotic use in livestock, specifically the use of antibiotics for growth promotion of food animals. This review article summarizes the recent knowledge of molecular acquisition of antimicrobial resistance and the effects of implementation of antibiotic growth promoter bans on the spread of antimicrobial resistant bacteria in animals and humans. In this article, we also discuss the main zoonotic transmission routes of antimicrobial resistance and novel approaches designed to prevent or slow down the emergence and spread of antimicrobial resistance worldwide. Finally, we provide future perspectives associated with the control and management of the emergence and spread of antimicrobial resistant bacteria.

Characterization of absorbed and produced constituents in goat plasma urine and faeces from the herbal medicine Gelsemium elegans by using high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Ethnopharmacological relevanceHerbal medicine contains hundreds of natural products, and studying their absorption, metabolism, distribution, and elimination presents great challenges. Gelsemium elegans (G. elegans) is a flowering plants in the Loganiaceae family. The plant is known to be toxic and has been used for many years as a traditional Chinese herbal medicine for the treatment of rheumatoid arthritis, neuropathic pain, spasticity, skin ulcers and cancer. It was also used as veterinary drugs for deworming, promoting animal growth, and pesticides. At present, studies on the metabolism of G. elegans have primarily focused on only a few single available reference ingredients, such as koumine, gelsemine and gelsedine. Material and methodsThe goal of this work is to elucidate the overall metabolism of whole G. elegans powder in goats using high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC/QqTOF-MS). ResultsAnalyses of plasma, urine and fecal samples identified or tentatively characterized a total of 44 absorbed natural products and 27 related produced metabolites. Gelsedine-type, sarpagine-type and gelsemine-type alkaloids were the compounds with the highest metabolite formation. In the present study, most natural products identified in G. elegans were metabolized through glucuronidation and oxidation. Hydrogenation, dehydrogenation and demethylation also occurred. ConclusionTo our knowledge, this is the first report of the metabolite profiling of the G. elegans crude extract in goats, which is of great significance for a safer and more rational application of this herbal medicine.

Koumine Alleviates Lipopolysaccharide-Induced Intestinal Barrier Dysfunction in IPEC-J2 Cells by Regulating Nrf2/NF-B Pathway.

Gelsemium elegans Benth. (G. elegans), a traditional Chinese medicine, has great potential as an effective growth promoter in animals, however, the mechanism of its actin remains unclear. Here, we evaluated the protective effects of koumine extract from G. elegans against lipopolysaccharide (LPS)-induced intestinal barrier dysfunction in IPEC-J2 cells through alleviation of inflammation and oxidative stress. MTT and LDH assays revealed that koumine significantly reduced LPS cytotoxicity. Transepithelial electrical resistance (TEER) and cell monolayer permeability assays showed that koumine treatment attenuated the LPS-induced intestinal barrier dysfunction with no particularly different effects in tight junction proteins such as ZO-1, claudin-1, and occludin. LPS-triggered inflammatory response was also suppressed by koumine, as evidenced by the downregulated inflammatory factors, including TNF-, IL-6, IL-1, NO, iNOS, and COX-2, which was closely connected with the inhibition of NF-B pathway for the decrease of phosphorylation of IB and NF-B and nuclear translocation of p-p65. Amount of reactive oxygen species (ROS) and MDA induced by LPS was also reduced by koumine through activation of Nrf2 pathway, and increased in the levels of Nrf2 and HO-1 degradation of keap-1 to promote anti-oxidants, including superoxide dismutase (SOD) and catalase (CAT). To summarize, koumine-reduced the oxidative stress and inflammatory reaction triggered by LPS through regulation of the Nrf2/NF-B signaling pathway and preventing intestinal barrier dysfunction.

Effect of dietary inclusion of 1% or 3% of native chicory inulin on the large intestinal mucosa proteome of growing pigs

Native chicory inulin is one of the promising alternatives to replace antibiotic growth promoters in young animals. Several potential mechanisms of prebiotic action have been proposed, such as modification of the intestinal microbiota composition leading to improved epithelial integrity and gut mucosal immunity of the host. The current study was focused on inulin effect on the large intestinal proteome and its implications for gut barrier functions. Therefore, we used proteomic techniques to determine changes in the large intestinal mucosa proteome of growing pigs after 40-day supplementation with native chicory inulin. The experiment was performed on 24 piglets fed from the 10th day of life an unsupplemented cereal-based diet or inulin-enriched diets (1% or 3%) with an average degree of polymerisation ≥ 10. At the age of 50 days, animals were sacrificed and tissue samples were collected from the cecum, and proximal and distal colon. Feeding diets supplemented with both levels of native inulin increased cecal and colonic expression of molecular chaperones, protein foldases and antioxidant proteins, which are collectively responsible for maintaining mucosal cell integrity as well as protecting against endotoxins and reactive oxygen species. This may confirm the beneficial effect of inulin on the gut health in growing pigs.

VEGF/Flk1 Mechanism is Involved in Roxarsone Promotion of Rat Endothelial Cell Growth and B16F10 Xenograft Tumor Angiogenesis

The potential angiogenic effect of roxarsone, a feed additive widely used to promote animal growth worldwide, was demonstrated recently. We explored the mechanism of vascular endothelial growth factor (VEGF) and its receptor (VEGFR) in roxarsone promotion of rat vascular endothelial cells (ECs) and B16F10 mouse xenografts. ECs were treated with 0.1–50 μM roxarsone or with roxarsone plus 10 ng/mL VEGF, VEGFR1 (Flt1), or VEGFR2 (Flk1) antibodies for 12–48 h to examine their role in cell growth promotion. Small interfering RNA (siRNA) targeting Vegf, Flt1, and Flk1 were transfected in the ECs, and we measured the expression level, cell proliferation, migration, and tube formation ability. The siRNA targeting Vegf or Flk1 were injected intratumorally in the B16F10 xenografts of mice that received 25 mg/kg roxarsone orally. Cell viability and VEGF expression following roxarsone treatment were significantly higher than that of the control (P < 0.05), peaking following treatment with 1.0 μM roxarsone. Compared to roxarsone alone, the VEGF antibody decreased cell promotion by roxarsone (P < 0.05), and the Flk1 antibody greatly reduced cell viability compared to the Flt1 antibody (P < 0.01). Roxarsone and Flk1 antibody co-treatment increased supernatant VEGF significantly, while cellular VEGF was obviously decreased (P < 0.01), whereas there was no significant difference following Flt1 antibody blockade. The siRNA against Vegf or Flk1 significantly attenuated the roxarsone promotion effects on EC proliferation, migration, and tube-like formation (P < 0.01), whereas the siRNA against Flt1 effected no obvious differences. Furthermore, the RNA interference significantly weakened the roxarsone-induced increase in xenograft weight and volume, and VEGF and Flk1 expression. Roxarsone promotion of rat EC growth, migration, and tube-like formation in vitro and of B16F10 mouse xenograft model tumor growth and angiogenesis involves a VEGF/Flk1 mechanism.

Effect of energy intake and L-carnitine on fattening performance, carcass traits, meat quality, blood metabolites, and gene expression of lamb

• LPL and FASN were increased in adipose tissues with energy intake increasing, while LIPE and SCD were decreased. • L-carnitine supplementation did not improve growth performance and mutton quality. • L-carnitine could be used as a potential feed additive to inhibit fat accumulation in sheep. A 70-day feeding experiment was conducted on Tan sheep ( Ovis ) to study the effects of energy intake (low, medium, or high) and/or L -carnitine supplementation (0 or 200 ppm) on fattening performance, carcass traits, meat quality, and expression of lipid metabolism associated genes. A 2 × 3 factorial arrangement was designed, 144 lambs (14.21 ± 0.30 kg) were randomly divided into six groups of four replicates (six lambs per replicate). At the end of feeding experiment, 24 lambs were slaughtered and sampled to analyze indexes. The results showed that live body weight (LBW), average daily gains (ADG), tail fat weight, GR values, and carcass weight increased with increasing energy intake. Increased energy intake significantly increased cooked meat percentage, shear force, and the content of crude protein (CP), ash, and crude fat (EE) in muscle. L -carnitine supplementation significantly reduced tail fat weight, GR values, and the content of CP and EE in muscle, while cooked meat percentage and water loss rate significantly increased. However, L -carnitine supplementation did not affect the LBW and ADG indexes. The effects of L -carnitine or energy intake did not significantly affect amino acid compositions of the longissimus dorsi (LD) muscle. High-energy intake resulted in higher blood urea nitrogen concentrations; in contrast, no significant effects of energy intake were observed on total cholesterol (TC), triglyceride (TG), and glucose (GLU) concentrations. In addition, L -carnitine supplementation in the high-energy group reduced GLU serum concentrations, but did not affect the concentrations of TC and TG. The investigation of gene expression showed that lipoprotein lipase and fatty acid synthase were significantly increased in the liver, tail fat, and subcutaneous fat with energy intake, while lipase E (hormone sensitive type) and stearoyl-CoA desaturase gene expression were significantly decreased. Furthermore, the effects of L -carnitine supplementation on gene expression were opposite to those of energy intake. Significant interaction was found between energy intake and L -carnitine supplementation for EE content in muscle, blood biochemical index, and amino acid compositions in the LD muscle. In conclusion, high-energy diets promote animal growth and production performance, while accelerating fat deposition. L -carnitine supplementation had slightly effect on the improvement of performance and lamb quality, while effectively counteracting the negative influence of high-energy intake, particularly inhibiting fat accumulation.