Review: Mechanism, effectiveness, and the prospects of medicinal plants and their bioactive compounds in lowering ruminants' enteric methane emission.

Animal nutritionists continue to investigate new strategies to combat the challenge of methane emissions from ruminants. Medicinal plants (MPs) are known to be beneficial to animal health and exert functional roles in livestock due to their phytogenic compounds with antimicrobial, immunostimulatory, antioxidative, and anti-inflammatory activities. Some MP has been reported to be anti-methanogenic and can effectively lower ruminants' enteric methane emissions. This review overviews trends in MP utilization in ruminants, their bioactivity and their effectiveness in lowering enteric methane production. It highlights the MP regulatory mechanism and the gaps that must be critically addressed to improve its efficacy. MP could reduce enteric methane production by up to 8-50% by regulating the rumen fermentation pathway, directing hydrogen toward propionogenesis, and modifying rumen diversity, structure, and population of the methanogens and protozoa. Yet, factors such as palatability, extraction techniques, and economic implications must be further considered to exploit their potential fully.

Gastrointestinal anthelmintic plants used on small ruminants in Benin: Traditional use and scientific results - Review.

In Benin, livestock breeders frequently use medicinal plants to treat gastrointestinal diseases in small ruminants. The aim of this review is to list the plants traditionally used in this context and to present the scientific findings on the efficacy of these plants. An extensive search was carried out using PubMed, Scopus, ScienceDirect, Biomed Central and Google Scholar databases to collect data, with combinations of relevant french and english keywords such as "ethnobotanical survey", "anthelmintic properties", "medicinal plants", "gastrointestinal parasites", "digestive strongyles", "Haemonchus", "Trichostrongylus", "small ruminants", "sheep", "goats" and "Benin". A total of 45 published articles met the eligibility criteria. This review listed 123 plants used by breeders to treat gastrointestinal ailments in small ruminants. The most commonly used parts are leaves and barks, and the most common forms are decoction, maceration and powder. Scientific studies have demonstrated the anthelmintic properties of 18 plants, including Zanthoxylum zanthoxyloides, Newbouldia laevis, Mitragyna inermis and Combretum glutinosum. The powders or leaf extracts of these plants showed in vivo significant reductions of over 50% in egg excretion, larval establishment, viability and fertility of gastrointestinal strongyles in small ruminants. Extracts of these plants also revealed in vitro inhibitory activity of over 50% on egg hatching, larval migration and motility of gastrointestinal strongyles. This manuscript highlights the traditional use of anthelmintic plants in small ruminants in Benin and provides scientific results supporting the efficacy of these plants.

Initial diet shapes resistance-gene composition and fecal microbiome dynamics in young ruminants during nursing.

This study was conducted to examine how colostrum pasteurization affects resistance genes and microbial communities in calf feces. Forty female Holstein calves were randomly assigned to either the control (CON) group, which received unheated colostrum, or the pasteurized colostrum (PAT) group. The calves body weight was measured weekly before morning feeding. Calf starter intake were measured and recorded daily before morning feeding. Samples of colostrum were collected before feeding. Blood was collected on d 1 and 70 before morning feeding. Ten calves were randomly selected from each group (n = 20 calves total) for fecal sampling on d 3, 28, 56 and 70 for subsequent DNA extraction and metagenomic sequencing. Total bacterial counts in the colostrum were markedly higher in the CON group than in the PAT group. Pasteurized colostrum administration substantially reduced the ARO diversity and diminishes the abundance of Enterobacteriaceae, thereby decreasing their contribution to resistance genes. Pasteurization also reduced glucoside hydrolase-66 activity in 3-day-old calves which led to an increase in the activity of aminoglycoside antibiotics, resulting in 52.63 % of PAT-enriched bacteria acquiring aminoglycoside resistance genes. However, from the perspective of overall microbial community, the proportion of aminoglycoside, beta-lactam and tetracycline resistance genes carried by microbial community in PAT group was lower than CON group (P < 0.05). Fecal samples from the PAT group contained greater abundances of Subdoligranulum (P < 0.05) and Lachnospiraceae_NK4A136_group (P < 0.05) on days 28 and 70 compared to CON. Network analysis and abundance variations of the different bacteria obtained by linear discriminant analysis effect size analysis showed that pasteurized colostrum feeding reduced the interactions among related bacteria and maintained stability of the hind-gut microbiome. In conclusion, these findings underscore the intricate interactions between early diet, calf resistance-gene transmission and microbial dynamics, which should be carefully considered in calf-rearing practices.

Phytochemical analysis and anthelmintic activity of Combretum mucronatum leaf extract against infective larvae of soil-transmitted helminths including ruminant gastrointestinal nematodes.

BACKGROUND: Soil-transmitted helminths (STH) infect more than a quarter of the world's human population. In the absence of vaccines for most animal and human gastrointestinal nematodes (GIN), treatment of infections primarily relies on anthelmintic drugs, while resistance is a growing threat. Therefore, there is a need to find alternatives to current anthelmintic drugs, especially those with novel modes of action. The present work aimed to study the composition and anthelmintic activity of Combretum mucronatum leaf extract (CMLE) by phytochemical analysis and larval migration inhibition assays, respectively. METHODS: Combretum mucronatum leaves were defatted with petroleum ether and the residue was extracted by ethanol/water (1/1) followed by freeze-drying. The proanthocyanidins and flavonoids were characterized by thin layer chromatography (TLC) and ultra-high performance liquid chromatography (UPLC). To evaluate the inhibitory activity of this extract, larval migration assays with STH and GIN were performed. For this purpose, infective larvae of the helminths were, if necessary, exsheathed (Ancylostoma caninum, GIN) and incubated with different concentrations of CMLE. RESULTS: CMLE was found to be rich in flavonoids and proanthocyanidins; catechin and epicatechin were therefore quantified for standardization of the extract. Data indicate that CMLE had a significant effect on larval migration. The effect was dose-dependent and higher concentrations (1000 µg/mL) exerted significantly higher larvicidal effect (P < 0.001) compared with the negative control (1% dimethyl sulfoxide, DMSO) and lower concentrations (≤ 100 µg/ml). Infective larvae of Ascaris suum [half-maximal inhibitory concentration (IC50) = 5.5 µg/mL], Trichuris suis (IC50 = 7.4 µg/mL), and A. caninum (IC50 = 18.9 µg/mL) were more sensitive to CMLE than that of Toxocara canis (IC50 = 310.0 µg/mL), while infective larvae of Toxocara cati were largely unaffected (IC50 > 1000 µg/mL). Likewise, CMLE was active against most infective larvae of soil-transmitted ruminant GIN, except for Cooperia punctata. Trichostrongylus colubriformis was most sensitive to CMLE (IC50 = 2.1 µg/mL) followed by Cooperia oncophora (IC50 = 27.6 µg/mL), Ostertagia ostertagi (IC50 = 48.5 µg/mL), Trichostrongylus axei (IC50 = 54.7 µg/mL), Haemonchus contortus (IC50 = 145.6 µg/mL), and Cooperia curticei (IC50 = 156.6 µg/mL). CONCLUSIONS: These results indicate that CMLE exhibits promising anthelmintic properties against infective larvae of a large variety of soil-transmitted nematodes.

Application of the SeDeM system for the preparation of antiparasitic tablets from mesquite flour for use in sheep.

The use of herbal medicine to treat various diseases is becoming increasingly important as an alternative therapy. Numerous plants have been traditionally used for different purposes, including antiparasitic in humans and animals. Diseases caused by gastrointestinal parasites in ruminants, especially by the nematode Haemonchus contortus, cause large economic losses to the producers, whether by complications of the diseases or the cost of treatment. The main way of handling nematodiasis is by administering anthelmintic drugs, but their excessive use has the disadvantage of causing drug resistance; therefore, an alternative is the use of herbal medicine for this purpose. Mesquite (Prosopis spp.) has been used in Mexico to treat gastrointestinal diseases attributed to helminths. The present study aimed to characterize the rheological properties of mesquite flour using the SeDeM Expert System to determine its suitability for tablet production by direct compression. Direct compression technology facilitates the tableting process by reducing manufacturing costs. The results of the present study indicate that mesquite flour can be processed by direct compression. The latter could allow the manufacturing of economic tablets to treat infections by H. contortus in ruminants.

Enteric methane emission reduction potential of natural feed supplements in ewe diets.

Research into the potential use of various dietary feed supplements to reduce methane (CH4) production from ruminants has proliferated in recent years. In this study, two 8-wk long experiments were conducted with mature ewes and incorporated the use of a variety of natural dietary feed supplements offered either independently or in combination. Both experiments followed a randomized complete block design. Ewes were offered a basal diet in the form of ad libitum access to grass silage supplemented with 0.5 kg concentrates/ewe/d. The entire daily dietary concentrate allocation, incorporating the respective feed supplement, was offered each morning, and this was followed by the daily silage allocation. In experiment 1, the experimental diets contained 1) no supplementation (CON), 2) Ascophyllum nodosum (SW), 3) A. nodosum extract (EX1), 4) a blend of garlic and citrus extracts (GAR), and 5) a blend of essential oils (EO). In experiment 2, the experimental diets contained 1) no supplementation (CON), 2) A. nodosum extract (EX2), 3) soya oil (SO), and 4) a combination of EX2 and SO (EXSO). Twenty ewes per treatment were individually housed during both experiments. Methane was measured using portable accumulation chambers. Rumen fluid was collected at the end of both experiments for subsequent volatile fatty acid (VFA) and ammonia analyses. Data were analyzed using mixed models ANOVA (PROC MIXED, SAS v9.4). Statistically significant differences between treatment means were considered when P < 0.05. Dry matter intake was not affected by diet in either experiment (P > 0.05). Ewes offered EO tended to have an increased feed:gain ratio relative to CON (P < 0.10) and SO tended to increase the average daily gain (P < 0.10) which resulted in animals having a higher final body weight (P < 0.05) than CON. Ewes offered EX1 and SO emitted 9% less CH4 g/d than CON. The only dietary treatment to have an effect on rumen fermentation variables relative to CON was SW, which enhanced total VFA production (P < 0.05). In conclusion, the A. nodosum extract had inconsistent results on CH4 emissions whereby EX1 reduced CH4 g/d while EX2 had no mitigating effect on CH4 production, likely due to the differences in PT content reported for EX1 and EX2. SO was the only dietary feed supplement assessed in the current study that enhanced animal performance whilst mitigating daily CH4 production.

Reducing methane emissions from agriculture is vital to minimize the effects of global warming and to meet greenhouse gas reduction targets set by EU policy. In this experiment, a range of natural feed supplements were offered to mature ewes through the concentrated portion of their diet. Soya oil and brown seaweed extract reduced daily methane emissions by 9% when offered independently of each other; however, no reduction in methane was observed when combined. Additionally, inclusion of soya oil improved animal weight gain. Results from the current experiment may contribute to the development of a targeted dietary strategy to reduce methane emissions from livestock.

Autumn grass treated with a hydrolysable tannin extract versus lactic acid bacteria inoculant: Effects on silage fermentation characteristics and nutritional value and on performance of lactating dairy cows.

Hydrolysable tannins (HT) show potential as silage additive for autumn herbage silages, high in (rumen degradable) protein, as they may reduce proteolysis. Additionally, they have abilities to form pH-reversible tannin-protein complexes, non-degradable in the rumen but degradable in the abomasum and intestines of ruminants. Therefore they can improve milk N efficiency and shift N excretions from urine to faeces, possibly mitigating the environmental impact of ruminants. In this study, two small bunker silos were filled with autumn grass. One was treated with 20 g/kg DM HT extract (TAN) (TannoSan-L), the other with 8 mg/kg DM inoculant containing lactic acid bacteria (INO) (Bonsilage Fit G). Secondly, micro-silos (2.75 L) were filled with four treatments; (1) grass without additive (CON) (n = 5); (2) TAN (n = 5); (3) INO (n = 5); and (4) TAN + INO (n = 5). The bunker silos were used in a cross-over feeding experiment with periods of 4 weeks involving 22 lactating Holstein cows (average ± SD: 183 ± 36.3 days in milk, 665 ± 71.0 kg body weight, and 33.8 ± 3.91 kg/day milk yield). The HT dose was insufficient to reduce proteolysis or alter chemical composition and nutritional value in the micro- and bunker silages. Including grass silage added with TAN (3.2 g HT/kg DM) in the diet, did not affect feed intake nor fat and protein corrected milk yield in comparison to feeding the grass silage added with INO in a similar diet. The TAN-fed cows had an increased faecal N excretion and decreased apparent total-tract N and organic matter digestibility, but no improvement in the cows' N utilization could be confirmed in milk and blood urea levels. Overall, feeding an autumn grass silage treated with 20 g/kg chestnut HT extract did not affect the performance of dairy cows in comparison to feeding an autumn grass silage treated with a lactic acid bacteria inoculant.

Ethnoveterinary uses of forage plants for domesticated ruminants in Malakand agency, Pakistan.

Plant ethnoveterinary uses are evident in various studies around the world, but the ethnoveterinary practices of forage species are not widely reported. Traditional knowledge is rapidly disappearing because of urbanization and commercial activities. The purpose of this study was to document plant species used by the local communities in Malakand Agency, Pakistan for foraging and ethnoveterinary purposes. Twenty different localities in the study area were surveyed for documentation of forage species and related traditional ethnoveterinary knowledge used for livestock. Semistructured questionnaires and field walks were used to conduct 67 interviews with local farmers and herdsmen. A total of 91 forage species from 26 families were documented, as well as their ethnoveterinary applications. Poaceae and Fabaceae were dominant families with 45% and 15% of species respectively. Among the forage species documented, 62 were highly palatable, 26 were moderately palatable and 12 were less palatable. The region's major veterinary diseases are flu, ringworms, inflammations, low milk production, constipation, bloat, mastitis, pneumonia and wounds. The 62 forage species were reported for the first time for various veterinary uses. This study revealed that local communities commonly use a diverse range of forage species in conjunction with indigenous knowledge of ethnoveterinary uses. These forage species have the potential to overcome the recent fodder shortage. Such studies will be beneficial to the commercial production of such forage species.

Can freshwater plants and algae act as an effective feed supplement to reduce methane emissions from ruminant livestock?

Methane production by livestock is a substantial component of greenhouse gas emissions worldwide. The marine red algae, Asparagopsis taxiformis, has been identified as a possible supplement in livestock feeds due to its potent inhibition of methane production but currently is unable to be produced at scale. Finding additional taxa that inhibit methane production is therefore desirable. Here we provide foundational evidence of methanogenesis-inhibiting properties in Australian freshwater plants and algae, reviewing candidate species and testing species' chemical composition and efficacy in vitro. Candidate plant species and naturally-occurring algal mixes were collected and assessed for ability to reduce methane in batch testing and characterised for biochemical composition, lipids and fatty acids, minerals and DNA. We identified three algal mixes and one plant (Montia australasica) with potential to reduce methane yield in in vitro batch assay trials. All three algal mixes contained Spirogyra, although additional testing would be needed to confirm this alga was responsible for the observed activity. For the two samples that underwent multiple dose testing, Algal mix 1 (predominantly Spirogyra maxima) and M. australasica, there seems to be an optimum dose but sources, harvesting and storage conditions potentially determine their methanogenesis-inhibiting activity. Based on their compositions, fatty acids are likely to be acting to reduce methane in Algal mix 1 while M. australasica likely contains substantial amounts of the flavonoids apigenin and kaempferol, which are associated with methane reduction. Based on their mineral composition, the samples tested would be safe for livestock consumption at an inclusion rate of 20%. Thus, we identified multiple Australian species that have potential to be used as a feed supplement to reduce methane yield in livestock which may be suitable for individual farmers to grow and feed, reducing complexities of supply associated with marine alternatives and suggesting avenues for investigation for similar species elsewhere.

Discrimination of different feed additives and poly-herbal formulations based on their untargeted phytochemical profiles.

INTRODUCTION: Feed additives represents a valid tool in animal nutrition to improve animal performance and livestock productivity under a sustainable perspective; however, there is a paucity of information about their comprehensive metabolomic and bioactive profiles. OBJECTIVE: In this study, we tested the ability of an untargeted metabolomics approach to discriminate nine commercial feed additives and unique blends of botanical extracts used in both ruminant and non-ruminant nutrition, according to their phytochemical profiles and different in vitro bioactive properties. METHODS: An ultra-high-performance liquid chromatography coupled with Orbitrap mass spectrometry and multivariate statistics were combined to search for potential markers, in order to better discriminate the different commercial samples. RESULTS: Several phytochemicals were identified, namely alkaloids, phenolics, organosulfurs, and terpenoids. The polyherbal formulation Zigbir was the best source of phytochemicals, accounting for a cumulative total content of phytochemicals equal to 3.03 mg Eq./g, being particularly abundant in terpenoids, stilbenes, phenolic acids, and small-molecular-weight phenolics. Multivariate statistics allowed to group the different products in 2 bioactive subclusters. The diterpenoid andrographolide recorded the highest abundance in Zigbir and Sangrovit. The most predictive biomarkers were: piperine, isoquercitrin, 6-methylthiohexyldesulfoglucosinolate, 6-methylumbelliferone, benzoic acid, (+)-(1R,2R)-1,2-diphenylethane-1,2-diol, and piperitenone. Flavonoids were highly correlated with both in vitro antioxidant and enzyme inhibition assays. CONCLUSIONS: Our findings provide new insights into the comprehensive phytochemical composition of commercial feed additives and blend of botanical extracts used for both ruminant and non-ruminant nutrition. A great importance of polyphenols in relation to the biological activities was detected.

Challenges and opportunities for reducing anthelmintic use in ruminant livestock systems: Insights from a sheep farmer survey in France.

Today's level of anthelmintic use in livestock production is a major threat to both the livestock industry and the environment. In this context, the research community is looking for ways to equip farmers with preventive and treatment strategies that can decrease livestock-industry dependence on anthelmintics. Production practices for a sustainable control of parasites have been advocated for almost forty years, but farmers' uptake of these practices has been too slow to address the issues at stake. In this paper, we examine the rationales behind the under-adoption of sustainable worm control practices in grassland-based livestock systems. This research builds on 25 semi-structured interviews with dairy sheep farmers in southwestern France. The interview material was analysed via qualitative discourse analysis. We highlight farmers' social representations and rationales underpinning adoption or non-adoption of the 'low anthelmintics use' strategy. We identify six profiles for nematode control according to the way each farmer included treatment and coprology in their on-farm practice. We identify that the low-use strategy has low adoption potential due to its low perceived relative advantage; low perceived trialability; unclear compatibility with previous experiences, needs, and values; and higher complexity than the status quo option. We show that holistic, pro-environmental, and collaborative attitudes are associated with adoption of the low-use strategy. We then discuss ways to improve uptake, such as increased communication, trainings, and farm visits involving farmers, extension agents and veterinarians.

Interventions to change antimicrobial use in livestock: A scoping review and an impact pathway analysis of what works, how, for whom and why.

Antimicrobial resistance (AMR) is a public health threat responsible for 700,000 deaths per year worldwide. Antimicrobial use (AMU) in livestock contributes to AMR in animal and public health. Therefore, it is essential to implement effective interventions towards better AMU in livestock. However, there is a lack of evidence to inform decision-makers of what works, how, for whom and why and how effective interventions can be adapted to different contexts. We conducted a scoping review and an impact pathway analysis to systematically map the research done in this area and to inform evidence-based and context-appropriate policies. We followed the PRISMA-ScR requirements and searched Web of Science, PubMed and Scopus databases to identify studies in English or French languages, in open access and published between 2000 and 2022. We selected thirty references addressing twenty-eight different interventions that were successful in changing AMU in livestock. We used an impact pathway logic model as an analytic framework to guide the technical aspects of the scoping review process and to identify the complex relationships between outputs, outcomes, impacts and contextual factors. A majority of interventions managed to improve AMU by changing herd and health management practices (ni=18). We identified intermediate outcomes including change in the veterinarian-farmer relationship (ni=7), in knowledge and perception (ni=6), and in motivation and confidence (ni=1). Twenty-two studies recorded positive impacts on animal health and welfare (ni=11), technical performances (ni=9), economic performances (ni=4) and AMR reduction (ni=4). Interventions implemented different strategies including herd and health management support (ni=20), norms and standards (ni=11), informational and educational measures (ni=10), economic support (ni=5). Studies were mainly in European countries and in pig and large ruminants farming. Most interventions targeted farmers or veterinarians but we identified other major and influential actors including authority and governmental organizations, academics and research, organization of producers or veterinarians, herd advisors and technicians, laboratories, and public opinion. Key success factors were knowledge and perception (ni=14), social factors (ni=13), intervention characteristics (ni=11), trajectory and ecosystem of change (ni=11), economic factors (ni=9), herd and health status (ni=8), data access and monitoring (ni=4). This review describes a paucity of impact assessment of interventions towards better AMU in livestock. There is no one-size-fits-all transition pathway but we inform decision-makers about the most successful interventions that work, how, for whom and why. The impact pathway analysis provided a holistic view of the successful change processes and the complex relationships between outputs, outcomes, impacts and contexts.

Modulation of feed digestibility, nitrogen metabolism, energy utilisation and serum biochemical indices by dietary Ligularia virgaurea supplementation in Tibetan sheep.

Ligularia virgaurea is the most widely functional native herbage in the alpine meadow pastures of the Qinghai-Tibet Plateau (QTP) and has multiple pharmacological and biological activities. The effect of L. virgaurea as a dietary component on the digestion and metabolism of sheep was evaluated by conducting feeding trials in metabolic cages. Thirty-two Tibetan yearling rams (29 ± 1.56 kg BW) were randomly allotted to four groups included in a completely randomised design with eight animals per treatment. Sheep were fed a basal diet (freshly native pasture) without the addition of L. virgaurea (control) or with the addition of L. virgaurea (100, 200, or 300 mg/kg BW per day) for 45 days. Addition of L. virgaurea to the diet of Tibetan sheep was found to influence the average daily gain (quadratic [Q], P < 0.001), feed conversion ratio (Q, P = 0.002), CH4 emissions (linear [L], P = 0.029), DM (Q, P = 0.012), neutral detergent fibre (Q, P = 0.017), acid detergent fibre (ADF) (Q, P = 0.027), and ether extract (EE) intake (Q, P = 0.026). Apparently, different levels of L. virgaurea affected the digestibility coefficients of DM, ADF, and EE (L, P > 0.05; Q, P < 0.05). The nitrogen (N) intake (Q, P = 0.001), retained nitrogen (Q, P < 0.001), and N utilisation efficiency (L, P > 0.05; Q, P ≤ 0.001) were also affected by the dietary inclusion of L. virgaurea. Effects of L. virgaurea feeding were also witnessed on methane energy (CH4-E) (L, P = 0.029), gross energy (GE) (Q, P = 0.013), digestible energy (DE) (Q, P = 0.015), and metabolisable energy (ME) intake (Q, P = 0.015). Energy utilisation efficiency expressed as a proportion of GE intake (DE/GE intake, ME/GE intake, ME/DE intake, FE/GE intake, and CH4-E/GE intake) manifested quadratic changes (P < 0.05) with the increase in the L. virgaurea supplementation level. The addition of L. virgaurea increased the activity of superoxide dismutase (Q, P = 0.026) and glutathione peroxidase activity (Q, P = 0.039) in the serum. Overall, the greatest improvement of feed digestibility, N retention, energy utilisation, and antioxidant capacity of Tibetan sheep was yielded by the inclusion of 200 mg/kg BW per day of L. virgaurea. Therefore, the addition of an appropriate amount of L. virgaurea to the diet of Tibetan sheep is safe and natural, and may enhance the sustainability of small ruminant production systems in QTP areas.

Multi-Omics Reveals the Impact of Exogenous Short-Chain Fatty Acid Infusion on Rumen Homeostasis: Insights into Crosstalk between the Microbiome and the Epithelium in a Goat Model.

Emerging data have underscored the significance of exogenous supplementation of butyrate in the regulation of rumen development and homeostasis. However, the effects of other short-chain fatty acids (SCFAs), such as acetate or propionate, has received comparatively less attention, and the consequences of extensive exogenous SCFA infusion remain largely unknown. In our study, we conducted a comprehensive investigation by infusion of three SCFAs to examine their respective roles in regulating the rumen microbiome, metabolism, and epithelium homeostasis. Data demonstrated that the infusion of sodium acetate (SA) increased rumen index while also promoting SCFA production and absorption through the upregulation of SCFA synthetic enzymes and the mRNA expression of SLC9A1 gene. Moreover, both SA and sodium propionate infusion resulted in an enhanced total antioxidant capacity, an increased concentration of occludin, and higher abundances of specific rumen bacteria, such as "Candidatus Saccharimonas," Christensenellaceae R-7, Butyrivibrio, Rikenellaceae RC9 gut, and Alloprevotella. In addition, sodium butyrate (SB) infusion exhibited positive effects by increasing the width of rumen papilla and the thickness of the stratum basale. SB infusion further enhanced antioxidant capacity and barrier function facilitated by cross talk with Monoglobus and Incertae Sedis. Furthermore, metabolome and transcriptome data revealed distinct metabolic patterns in rumen contents and epithelium, with a particular impact on amino acid and fatty acid metabolism processes. In conclusion, our data provided novel insights into the regulator effects of extensive infusion of the three major SCFAs on rumen fermentation patterns, antioxidant capacity, rumen barrier function, and rumen papilla development, all achieved without inducing rumen epithelial inflammation. IMPORTANCE The consequences of massive exogenous supplementation of SCFAs on rumen microbial fermentation and rumen epithelium health remain an area that requires further exploration. In our study, we sought to investigate the specific impact of administering high doses of exogenous acetate, propionate, and butyrate on rumen homeostasis, with a particular focus on understanding the interaction between the rumen microbiome and epithelium. Importantly, our findings indicated that the massive infusion of these SCFAs did not induce rumen inflammation. Instead, we observed enhancements in antioxidant capacity, strengthening of rumen barrier function, and promotion of rumen papilla development, which were facilitated through interactions with specific rumen bacteria. By addressing existing knowledge gaps and offering critical insights into the regulation of rumen health through SCFA supplementation, our study holds significant implications for enhancing the well-being and productivity of ruminant animals.

Alternatives to antibiotics in veterinary medicine: considerations for the management of Johne's disease.

Antibiotic resistance has become a major health concern globally, with current predictions expecting deaths related to resistant infections to surpass those of cancer by 2050. Major efforts are being undertaken to develop derivative and novel alternatives to current antibiotic therapies in human medicine. What appears to be lacking however, are similar efforts into researching the application of those alternatives, such as (bacterio)phage therapy, in veterinary contexts. Agriculture is still undoubtedly the most prominent consumer of antibiotics, with up to 70% of annual antibiotic usage attributed to this sector, despite policies to reduce their use in food animals. This not only increases the risk of resistant infections spreading from farm to community but also the risk that animals may acquire species-specific infections that subvert treatment. While these diseases may not directly affect human welfare, they greatly affect the profit margin of industries reliant on livestock due to the cost of treatments and (more frequently) the losses associated with animal death. This means actively combatting animal infection not only benefits animal welfare but also global economies. In particular, targeting recurring or chronic conditions associated with certain livestock has the potential to greatly reduce financial losses. This can be achieved by developing novel diagnostics to quickly identify ill animals alongside the design of novel therapies. To explore this concept further, this review employs Johne's disease, a chronic gastroenteritis condition that affects ruminants, as a case study to exemplify the benefits of rapid diagnostics and effective treatment of chronic disease, with particular regard to the diagnostic and therapeutic potential of phage.

Vitamins and Trace Minerals in Ruminants: Confinement Feedlot.

Trace minerals and vitamins are essential for optimizing feedlot cattle growth, health, and carcass characteristics. Understanding factors that influence trace mineral and vitamin absorption and metabolism is important when formulating feedlot cattle diets. Current feedlot industry supplementation practices typically exceed published trace mineral requirements by a factor of 2 to 4. Therefore, the intent of this review is to briefly discuss the functions of trace minerals and vitamins that are typically supplemented in feedlot diets and to examine the impact of dose of trace mineral or vitamin on growth performance, health, and carcass characteristics of feedlot cattle.

Low antimicrobial resistance in Escherichia coli isolates from two large Austrian alpine karstic spring catchments.

The increasing occurrence of antibiotic resistant bacteria poses a threat to global public health. Clinically relevant resistances also spread through the environment. Aquatic ecosystems in particular represent important dispersal pathways. In the past, pristine water resources have not been a study focus, although ingestion of resistant bacteria through water consumption constitutes a potentially important transmission route. This study assessed antibiotic resistances in Escherichia coli populations in two large well-protected and well-managed Austrian karstic spring catchments representing essential groundwater resources for water supply. E. coli were detected seasonally only during the summer period. By screening a representative number of 551 E. coli isolates from 13 sites in two catchments, it could be shown that the prevalence of antibiotic resistance in this study area is low. 3.4 % of the isolates showed resistances to one or two antibiotic classes, 0.5 % were resistant to three antibiotic classes. No resistances to critical and last-line antibiotics were detected. By integrating fecal pollution assessment and microbial source tracking, we could infer that ruminants were the main hosts for antibiotic resistant bacteria in the studied catchment areas. A comparison with other studies on antibiotic resistances in karstic or mountainous springs highlighted the low contamination status of the model catchments studied here, most likely due to the high protection and careful management while other, less pristine catchments showed much higher antibiotic resistances. We demonstrate that studying easily accessible karstic springs allows a holistic view on large catchments concerning the extent and origin of fecal pollution as well as antibiotic resistance. This representative monitoring approach is also in line with the proposed update of the EU Groundwater Directive (GWD).

Phytochemical profile and nematicidal activity of a hydroalcoholic extract from Cazahuate flowers (Ipomoea pauciflora M. Martens & Galeotti) against Haemonchus contortus infective larvae.

Haemonchus contortus (Hc) is a hematophagous parasite affecting the health and productivity of flocks. The administration of chemical anthelmintic drugs (AH) is the common method of deworming; however, generates resistance in the parasites to AH and it is a public health risk due to drug residues in milk, meat and sub-products. Natural compounds from plants are explored to diminish this parasitosis, improving their health and productivity, without the negative effects of AH. Ipomoea genus is a group of climbing plants belonging to the Convulvulaceae family possessing perennial leaves and tuberous roots. Medicinal properties has been attributed to this plant including nutritional agents, emetics, diuretics, diaphoretics, purgatives and pesticides. The objective of this study was assessing the in vitro nematocidal activity of a hydroalcoholic extract (HA-E) obtained from Ipomoea pauciflora (Cazahuate) flowers against Hc infective larvae (L3) and to identify its phytochemical profile (PhC-P). The assay was carried out using microtiter plates (MTP). Four HA-E concentrations were assessed and Ivermectin and distilled water were used as positive and negative control groups, respectively. Approximately 100 Hc L3 were deposited in each well (n=12) and incubated at 25-35°C for 7 days. Data were analyzed using ANOVA and a General Linear Model (GLM) followed by Tukey test (P<0.05). The treatments showing a concentration-dependent effect (CDE) were analyzed to identify their 50% and 90% lethal concentrations (CL50, 90) via a Probit Analysis. The highest mortality was observed at 50 mg/mL (82.64 ± 0.71%) and the lowest at 6.25 mg/mL (56.46 ± 2.49%), showing a CDE with increasing mortality from 6.25 to 50 mg/mL. The PhC-P revealed the presence of alkaloids, coumarins, flavonoids, tannins and triterpenes/ sterols. A HA-E from flowers of I. pauciflora will be considered to assess its potential use in the control of haemonchosis in small ruminants.

In vivo experimentally study the effect of Nigella Sativa silver nanoparticles for treatment of salmonella species causing diarrhea in ruminants.

Salmonellais one of the main etiological agents of infectious diarrhea in large and small ruminants but emergence of multidrug-resistant (MDR) strains faster rate than previously, leads to develop of MDR strains among animals needs different alternative therapeutic strategies. Our study was aimed to evaluate the effects of Nigella sativa silver nanoparticles (NS AgNPs) on specific pathogen-free (SPF) Wister rats. Nigella sativa silver nanoparticles were prepared and confirmed their formation by optical observations, UV-Vis spectroscopy, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Rats in group G2 were infected experimentally with Salmonella spp and treated with ciprofloxacin orally for duration of 6 days at a dose rat 10 mg/kg. On the other hand, rats in group G1 were infected with salmonella and treated for 20 days with NS AgNPs in oral dose of (10 mg/kg rats), and the results were compared to control groups G3 which received bacterial infection without treatment and G4 control negative. The results of optical observation, UV-Vis spectroscopy, TEM, and SEM revealed typical characteristics of prepared NS AgNPs. Liver, kidney function biomarkers, hematologic analysis, and histological examination the tissues of liver, kidney, and stomach of rat's model improved that NS AgNPs has antimicrobial effect and has the ability to decrease the inflammatory reaction caused by Salmonella spp infection. The results of our study indicate that NS AgNPs are effective in controlling MDR Salmonella spp in vivo without causing any adverse effects. Moreover, our findings suggest that reducing the use of antimicrobials could be a key factor in the fight against antimicrobial resistance and can provide valuable insights into identifying the most appropriate treatment strategies to tackle this issue effectively in the future.

Effects of duration of exposure, co-supplementation with iron and Nippostrongylus brasiliensis infection on accumulation of trichloroacetic acid-insoluble copper in rats given molybdate in drinking water.

Thiolation can convert molybdate (MoO4) into a series of thiomolybdates (MoSxO4-x) in the rumen, terminating in tetrathiomolybdate (MoS4), a potent antagonist of copper absorption and, if absorbed, donor of reactive sulphide in tissues. Systemic exposure to MoS4 increases trichloroacetic acid-insoluble copper (TCAI Cu) concentrations in the plasma of ruminants and induction of TCAI Cu in rats given MoO4 in drinking water would support the hypothesis that rats, like ruminants, can thiolate MoO4. Data on TCAI Cu are presented from two experiments involving MoO4 supplementation that had broader objectives. In experiment 1, plasma Cu concentrations (P Cu) tripled in female rats infected with Nippostrongylus brasiliensis after only 5 days exposure to drinking water containing 70 mg Mo L-1, due largely to an increase in TCAI Cu; activities of erythrocyte superoxide dismutase and plasma caeruloplasmin oxidase (CpOA) were unaffected. Exposure for 45-51 days did not raise P Cu further but TCA-soluble (TCAS) Cu concentrations increased temporarily 5 days post infection (dpi) and weakened the linear relationship between CpOA and TCAS Cu. In experiment 2, infected rats were given less MoO4 (10 mg Mo L-1), with or without iron (Fe, 300 mg L-1), for 67 days and killed 7 or 9 dpi. P Cu was again tripled by MoO4 but co-supplementation with Fe reduced TCAI Cu from 65 ± 8.9 to 36 ± 3.8 µmol L-l. Alone, Fe and MoO4 each reduced TCAS Cu in females and males when values were higher (7 and 9 dpi, respectively). Thiolation probably occurred in the large intestine but was inhibited by precipitation of sulphide as ferrous sulphide. Fe alone may have inhibited caeruloplasmin synthesis during the acute phase response to infection, which impacts thiomolybdate metabolism.