Mycotoxins are toxic secondary metabolites produced by fungi, and frequently encountered in cereals that compose a major part of livestock diets. Fumonisin B1 (FB1) is one of the most prevalent toxins in feed, posing a risk to animal health and productivity. Considering mycotoxin mitigation strategies, adsorbents are an advantageous alternative for reducing mycotoxin uptake by animals. In this context, the main objective of this study was to develop an in vitro protocol for FB1 adsorption and assess the binding efficacy of five formulated products composed of inorganic clay and algae extracts. For this purpose, algae-based formulations were provided by Olmix (Bréhan, France), and multiple parameters were evaluated for in vitro testing, such as pH and mycotoxin concentration. After the selection of adequate conditions, the adsorption capacities of five algae-based products were compared. Results indicate that the adsorption capacity of the algae-based products is mainly linked to the presence of algae, especially green algae; which present a high polysaccharide content in their cell walls as binding sites for mycotoxins. The use of algae for mycotoxin adsorption remains underexplored, but the findings of the present work indicate that algae-based products are effective for FB1 control in animal feed.
This study investigated biomarkers of fumonisin exposure in pigs fed diets contaminated with fumonisins at the European Union’s maximum recommended level. Pigs were assigned to either a fumonisin (FB) diet or a fumonisin plus AlgoClay (FB + AC) diet for durations of 4, 9, and 14 days. At 14 days, the plasma Sa1P:So1P ratio increased in pigs fed the FB diet, while the Sa:So ratio remained unchanged. In the liver, FB1 was detected at four days of exposure, with the concentration tending to increase through day 14. The Sa:So and C22-24:C16 ratios of 18:1-, 18:2-, and m18:1-ceramides were elevated at 9 and 14 days, respectively. In the kidneys, FB1 was only detectable at 14 days, and the Sa:So and C22-24:C16 ratios of 18:1-ceramides were increased. In both the liver and kidneys, the increase in the C22-24:C16 ratio was attributed to a reduction of C16 ceramides. In the lungs, no FB1 was detected; however, the Sa:So and Sa1P:So1P ratios increased, and C16 ceramide concentrations decreased at 14 days. Feeding the pigs the FB + AC diet resulted in a reduction of the FB1 tissue-to-feed ratio in the liver and kidneys but did not affect the Sa:So or Sa1P:So1P ratios. Interestingly, the decreases in C16 ceramides observed in the FB diet group were no longer detectable in the FB + AC group. Overall, these findings highlight the complexity of the relationship between FB1 tissue concentrations and sphingolipid changes, suggesting that a comprehensive analysis of multiple biomarkers is required to fully understand fumonisin’s effects.
African swine fever (ASF) is one of the deadliest swine diseases, causing significant economic losses, threatening food security, and limiting pig production in affected countries. In the absence of an effective ASF vaccine, prevention and control of ASF depend mainly on effective biosecurity measures. In this study, the efficacy of SAFER®, a powdered disinfectant containing clay, an acid complex, and the active ingredient thyme essential oil, was tested against the ASF virus. The results showed that ASFV isolate (VNUA/HY/ASF1/Vietnam/2019) was inactivated by 3.5 and 5 Log10HAD50/ml after 20 and 120 min of treatment with SAFER®, respectively. When body fluids contaminated with ASFV, such as blood, saliva, urine, and feces, were treated with SAFER® for 20 min, the ASFV titer was reduced by 1.6, 2.2, 2.0, and 2.2 Log10HAD50/ml, respectively.
Green macroalgae (Ulva sp.) and red macroalgae (Solieria sp.) were processed to produce eight different crude extracts enriched for marine sulphated polysaccharides (MSP). While all extracts showed direct anti-bacterial effects to some degree, two red algal extracts, in particular, showed high activity against several pathogenic fish bacteria in vitro. Stimulation of head kidney leukocytes (HKLs) in vitro with MSP-rich extracts showed fish species specific differences. In Nile tilapia, HKLs showed a dose dependent production of reactive oxygen species (ROS) following stimulation with Ulva-derived extracts, while stimulation with Solieria-derived extracts did not induce ROS production. In rainbow trout, HKLs showed relatively high reactive ROS potential and Solieria-derived extracts could induce significant ROS production, albeit without a clear dose dependent response. Gene expression of in vitro stimulated HKLs showed a clear induction of most cytokines measured (il1b, il10, tnfa, ifny, il12p40), with differences between species. Although cytokine gene expressions were more prominently induced in HKLs of Nile tilapia than in HKLs of rainbow trout, immunomodulatory effects of both, Ulva- and Solieria-derived extracts, always appeared evident. It is likely that HKLs have the ability to sense presence of MSP, via so far uncharacterized pattern recognition receptors which have known downstream signalling pathways. Expression of some genes associated with Toll-like Receptor (TLR) signalling, such as irak1 and especially the expression of genes associated with C-type Lectin Receptor (CLR) signalling, such as card9 and bcl10 were evident following stimulation with MSP-rich extracts. Possibly, immunomodulatory effects of MSP could be regulated by at least a CLR-mediated signalling, at least in Nile tilapia, for which most if not all red algae and green algae extracts induced changes in gene expression of card9 and bcl10. Overall, induction of ROS production and gene expression read-outs suggest immunomodulatory effects of MSP-rich extracts derived from green algae (Ulva sp.) and red algae (Solieria sp.), at least in vitro. The observed effects suggest clear fish species specific differences between the effects of MSP-rich extracts.
The biological properties of sphinganine-(d18:0)-, sphingosine-(d18:1)-, deoxysphinganine-(m18: 0)-, deoxysphingosine-(m18:1)-, deoxymethylsphinganine-(m17:0)-, deoxymethylsphingosine-(m17:1)-, sphingadienine-(d18:2)-, and phytosphingosine-(t18:0)-sphingolipids have been reported to vary, but little is known about the effects of fumonisins, which are mycotoxins that inhibit ceramide synthase, on sphingolipids other than those containing d18:0 and d18:1. Thirty chickens divided into three groups received a control diet or a diet containing 14.6 mg FB1 + FB2/kg for 14 and 21 days. No effects on health or performance were observed, while the effects on sphingoid bases, ceramides, sphingomyelins, and glycosylceramides in liver, kidney, and plasma varied. The t18:0 forms were generally unaffected by fumonisins, while numerous effects were found for m18:0, m18:1, d18:2, and the corresponding ceramides, and these effects appeared to be similar to those observed for d18:0-, and d18:1-ceramides. Partial least square discriminant analysis showed that d18:1- and d18:0-sphingolipids are important variables for explaining the partitioning of chickens into different groups according to fumonisins feeding, while m17:1-, m18:0-, m18:1-, d18:2-, and t18:0-sphingolipids are not. Interestingly, the C22-C24:C16 ratios measured for each class of sphingolipid increased in fumonisin-fed chickens in the three assayed matrices, whereas the total amounts of the sphingolipid classes varied. The potential use of C22-C24:C16 ratios as biomarkers requires further study.
The current control of gastrointestinal (GI) parasitic nematodes mainly relies on the widespread use of anthelmintics, which has inevitably led to resistance. Therefore, there is an urgent need to find new sources of antiparasitic compounds. Macroalgae represent a rich source of active molecules and are widely described as having medicinal properties. In the present study, we investigated the potential anthelmintic activity of aqueous extracts from three species of algae (Bifurcaria bifurcata, Grateloupia turuturu and Osmundea pinnatifida) on the murine parasite Heligmosomoides polygyrus bakeri. Using a set of complementary in vitro tests, including larval development assays, egg hatching tests and nematicidal activity assays on larvae and adults, we report the nematicidal activity of aqueous extracts of B. bifurcata. In addition, aqueous extract fractionation using liquid/liquid partitioning with a solvent of increasing polarity was performed in order to identify the groups of active molecules underlying the anthelmintic activity. Non-polar extracts (heptane, ethyl acetate) demonstrated high anthelmintic potential, highlighting the role of non-polar metabolites such as terpenes. Here, we highlight the strong anthelmintic potential of the brown alga B. bifurcata on a mouse model of GI parasites, thus confirming the strong interest in algae as natural alternatives for the control of parasitic nematodes.
Alteration of sphingolipid synthesis is a key event in fumonisins toxicity, but only limited data have been reported regarding the effects of fumonisins on the sphingolipidome. Recent studies in chickens found that the changes in sphingolipids in liver, kidney, lung, and brain differed greatly. This study aimed to determine the effects of fumonisins on sphingolipids in heart, gizzard, and breast muscle in chickens fed 20.8 mg FB1 + FB2/kg for 9 days. A significant increase in the sphinganine:sphingosine ratio due to an increase in sphinganine was observed in heart and gizzard. Dihydroceramides and ceramides increased in the hearts of chickens fed fumonisins, but decreased in the gizzard. The dihydrosphingomyelin, sphingomyelin, and glycosylceramide concentrations paralleled those of ceramides, although the effects were less pronounced. In the heart, sphingolipids with fatty acid chain lengths of 20 to 26 carbons were more affected than those with 14–16 carbons; this difference was not observed in the gizzard. Partial least squares-discriminant analysis on sphingolipids in the heart allowed chickens to be divided into two distinct groups according to their diet. The same was the case for the gizzard. Pearson coefficients of correlation among all the sphingolipids assayed revealed strong positive correlations in the hearts of chickens fed fumonisins compared to chickens fed a control diet, as well as compared to gizzard, irrespective of the diet fed. By contrast, no effect of fumonisins was observed on sphingolipids in breast muscle.
Most of the toxic effects of fumonisins can be related to sphingolipid alteration, but there is little sphingolipidomic data in animals fed fumonisins in organs other than the liver. This study aimed to measure fumonisin B1 (FB1) in kidney, lung, and brain and determine its effects on sphingolipids. Thirty chickens divided into three groups received a diet containing 20.8 mg FB1+FB2/kg for 0, 4, or 9 days. FB1 increased in kidney from 1.7 to 5.6 nmol/kg and in lung from 0.5 to 1 nmol/kg at 4 and 9 days, respectively. No FB1 was detected in brain. In kidney, sphinganine increased, C14-C16 ceramides decreased, whereas C18-C26 ceramides increased. Most of the changes in dihydroceramides, dihydrodeoxyceramides, deoxyceramides sphingomyelins, dihydrosphingomyelins, and hexosylceramides paralleled those on ceramides. In lung, sphinganine was unaffected by fumonisins, whereas sphinganine-1-phosphate increased. Other major changes corresponded to decreases in glycosylceramides. In brain, sphinganine was unchanged, whereas deoxysphinganine, sphingosine, C14-C20 ceramides, and C14-C20 sphingomyelins increased. These results revealed that alterations in sphingolipids in kidney were close to those measured in liver and could correspond to inhibition of ceramide synthase 5 activity. In contrast, effects of fumonisins in lung and brain cannot be explained by inhibition of ceramide synthase.
Marek’s disease (MD) is a highly contagious lymphoproliferative disease of chickens caused by an alphaherpesvirus, Marek’s disease virus (MDV). MD is presently controlled by systematic vaccination of animals, which protects efficiently against the development of clinical disease. However, MDV vaccines do not prevent the multiplication and spread of MDV field strains and may favor the emergence of strains with increased virulence. Therefore, MDV persists to be a major problem for the poultry industry and the development of new alternative strategies to control MDV is needed. Seaweed extracts have previously been shown to exert immunomodulatory and antiviral activities, especially against herpesviruses. The objective of the present study was to explore the effect of Ulva armoricana extracts on MDV infection in vitro. We could demonstrate that the ulvan extract as well as its vitamin-enriched formulation reduce the viral load by about 80% at 24 h post-infection in infected chicken fibroblasts at concentrations that are innocuous for the cells. We also observed a substantial decrease in MDV plaque size suggesting that ulvans impede MDV cell-to-cell spread in vitro. Moreover, we showed that ulvan extract could promote MDV reactivation in lymphoid cells. Our data provide the first evidence that the use of the ulvan extract could be a good alternative to limit MDV infection in poultry.
Porcine respiratory complex syndrome has a strong economic impact on the swine breeding sector, as well as a clear repercussion on the wellbeing of the animals, leading to overuse of antimicrobial molecules. Algal extracts used in short-term treatments are empirically recognized by farmers as having a positive effect on pigs' health, however, their mechanisms of action are not well known and more research is needed. Herein we studied the short and median term impact of three algal extracts, in vitro, on the pro-inflammatory and antiviral responses of porcine primary blood monocytes and alveolar macrophages, as well as the susceptibility of the treated cells to infection by Porcine Respiratory and Reproductive Syndrome Virus (PRRSV) and the Aujeszky's Disease Virus (ADV). All extracts presented a pro-inflammatory short-term effect, associated for two of them, with an inhibition of the PRRSV replication. Conversely, the three extracts presented an anti-inflammatory median term effect, with no impact on PRRSV replication. The observed immune modulation prompts us to test, in vivo, the anti-PRRSV action of algal extracts and strengthen the interest for this natural resource.
Chicken γδ T lymphocytes are present in a variety of tissues such as blood, spleen and intestine. They constitute a major cytotoxic population. In chicken, Salmonella immunization as well as vaccination against Newcastle disease virus are accompanied by an increase of γδ T lymphocytes in peripheral blood, which may be activated, and thus represent a protective immune response. It has been published that activation of avian γδ T cells can occur in a MHC non-restricted manner. Ulvans are complex sulfated polysaccharides composed of disaccharide repetitions found in the cell walls of green algae belonging to the genus Ulva. We recently demonstrated that a purified ulvan extract activates chicken heterophils and monocytes in vivo through TLR2 and TLR4 receptors when given in drinking water. We demonstrate here, that the same extract given once in drinking water at 25 and 50 mg/l, results in increased membrane expression of Major Histocompatibility Complex class 2 as soon as day 2, as detected using flow cytometry. We conclude chicken γδ T lymphocytes to be activated, or at least primed, in vivo, with the extract. Further experiments are required to fully understand whether their activation or priming is the result of direct and/or indirect mechanisms.
Macroalgae of the genus Ulva have long been used as human food. Local environmental conditions, among other factors, can have an impact on their nutrient and phytochemical composition, as well as on the value of the seaweed for food and non-food applications. This study is the first to initiate a comparison between commercial Ulva spp. from different European origins, France (FR, wild-harvested Ulva spp.), and Portugal (PT, farm-raised Ulva rigida), in terms of proximate composition, esterified fatty acids (FA), and polar lipids. The ash content was higher in PT samples, while FR samples had higher levels of proteins, lipids, and carbohydrates and other compounds. The profile of esterified FA, as well as FA-containing polar lipids at the class and species levels were also significantly different. The FR samples showed about three-fold higher amount of n-3 polyunsaturated FA, while PT samples showed two-fold higher content of monounsaturated FA. Quantification of glycolipids and phospholipids revealed, respectively, two-fold and three-fold higher levels in PT samples. Despite the differences found, the polar lipids identified in both batches included some lipid species with recognized bioactivity, valuing Ulva biomass with functional properties, increasing their added value, and promoting new applications, namely in nutraceutical and food markets.
Products extracted from natural resources are an increasing trend in several fields promoted by consumer demand. Allied to the importance attached to the concept of "natural product" should be the way the "natural product" is obtained. In this work, chlorophyll was extracted from batches of wild-harvested and farm-raised green macroalgae Ulva spp. from two different European locations, Portugal and France. The performance of different aqueous solutions of tensioactive compounds such as ionic liquids and common surfactants in the yield of extraction of chlorophyll was studied and the operational conditions of extraction were optimized. The effect of drying the biomass on the yield of extraction of chlorophyll was evaluated as well as the effect of both locations (and the specific conditions of each location in terms of nutrients, water temperature and light intensity) in chlorophyll production. After optimization of all operational conditions, a maximum yield of extraction of 5.96 mg(chl).(gdry) (-1)(algae) was obtained using 250 mM of tributyltetradecylphosphonium chloride ([P4,4,4,14]Cl). The use of this solvent has allowed the development of a cost-effective (conclusion obtained after the economic analysis) and efficient process capable of maintaining the stability of the final product for more than one month.
Fumonisins (FB) are mycotoxins known to exert most of their toxicity by blocking ceramide synthase, resulting in disruption of sphingolipid metabolism. Although the effects of FB on sphinganine (Sa) and sphingosine (So) are well documented in poultry, little information is available on their other effects on sphingolipids. The objective of this study was to analyze the effects of FB on the hepatic and plasma sphingolipidome in chickens. The first concern of this analysis was to clarify the effects of FB on hepatic sphingolipid levels, whose variations can lead to numerous toxic manifestations. The second was to specify the possible use of an alteration of the sphingolipidome as a biomarker of exposure to FB, in addition to the measurement of the Sa:So ratio already widely used. For this purpose, we developed an UHPLC MS/MS method that enabled the determination of 82 SL, including 10 internal standards, in chicken liver and plasma. The validated method was used to measure the effects of FB administered to chickens at a dose close to 20 mg FB1 + FB2/kg feed for 9 days. Significant alterations of sphingoid bases, ceramides, dihydroceramides, glycosylceramides, sphingomyelins and dihydrosphingomyelins were observed in the liver. In addition, significant increases in plasma sphinganine 1-phosphate, sphingosine 1-phosphate and sphingomyelins were observed in plasma. Interestingly, partial least-squares discriminant analysis of 11 SL in plasma made it possible to discriminate exposed chickens from control chickens, whereas analysis of Sa and So alone revealed no difference. In conclusion, our results show that the effects of FB in chickens are complex, and that SL profiling enables the detection of exposure to FB when Sa and So fail.
The digestive system of poultry breeders is highly solicited, especially late in the egg production period when the demand in lipids for yolk development increases. To maintain a good health status and optimal levels of egg production, the digestive system needs to be properly drained and stimulated. This study assesses the impact of the product DigestSea containing a sulphated polysaccharide extracted from green seaweeds named MSP®LIPIDS, on liver physiology and laying performance of breeding turkeys in comparison with a choline and sorbitol complex. The trial was performed in two buildings, from 23 to 28 weeks of laying. One group of 2,016 turkey breeders received the choline and sorbitol complex at 1 L/1,000 L of drinking water while the test group of 2,110 turkey breeders received DigestSea at a dosage of 0.5 L/1,000 L of drinking water, during 2 periods, first 10 days at 23 weeks of laying and again 5 days at 27 weeks of laying. Histological evaluation of the liver was performed at the end of the trial. The results show higher egg production in the DigestSea group with a significant reduction of the biliary canal hyperplasia and blood capillaries leucocytosis in the portal area, associated with a statistically significant reduction of lipids overload in the liver. Overall, our results show that the use of DigestSea containing MSP®LIPIDS helps maintain a high level of egg production and lower hepatic steatosis. In conclusion, the use of the product containing MSP®LIPIDS in breeding poultry production may be beneficial to maintain animal health and production levels. Further experiments are required to determine the mechanisms of action as a reduction of lipid resorption, metabolic changes, and an increased energy demand due to improving egg production.
The transfer of passive immunity from sows to piglets can be improved through the administration of immunostimulating products before farrowing. This study evaluated the immuno-stimulating effect of an algal sulfated polysaccharide extract (MSP extract) from the green algae Ulva armoricana when administrated orally to sows at the end of gestation. Four diets were tested: Control (no MSP extract), MSP1 (2 g/day of MSP extract), MSP2 (8 g/day), and MSP3 (16 g/day). The experimental diets were provided in two periods: before the last atrophic rhinitis vaccine booster, and a week before farrowing. Anti-Bordetella IgG antibodies were recorded in blood, colostrum, and milk, and total IgA were measured in colostrum and milk. Titer kinetics between the blood sampled before farrowing and colostrum displayed an increase in specific IgG for MSP3. Moreover, the MSP2 diet increased the level of total IgA in milk compared to the control group. Although the immuno-stimulating effect of MSP extract on piglet performance was not concurrent across the different supplementation levels, the present study supports the use of natural algae extract (MSP) as an immunomodulating solution in swine production.
The emergence of antimicrobial resistant infections from food is well documented in the scientific literature but, in this kind of matter, the public opinion is an important policy driver and is vastly forged by traditional media. Here, we propose a text mining study through about 500 articles from two reference daily U.S. newspapers to assess the media coverage of this issue. Our results indicate that, since the middle of the 80s, the two journals considered here adopted a very different narrative around the issue, echoing civil society concerns in one case and the official discourse in the other.