This research aimed to investigate the pharmacokinetics (PK), withdrawal time (WT) and hepatopancreas histological impact of doxycycline (DOX) in white leg shrimp (Litopenaeus vannamei). To determine PK parameters in hemolymph, hepatopancreas, and muscle, a single oral dose of 20 mg DOX/kg body weight was administered, following by interval sampling during 24 h. DOX concentrations were quantified by high-performance liquid chromatography coupled with tandem mass spectrometry, and PK parameter estimation was done using a one-compartmental model. The maximum concentrations in shrimp hemolymph, hepatopancreas and muscle were 1.09 µg/mL, 2.37 µg/g and 0.46 µg/g at 1.6 h, 0.23 h and 2 h, respectively. The pharmacokinetics/pharmacodynamics (PK/PD) properties were integrated based on the concentration-time curves of DOX in the hepatopancreas over the minimum inhibitory concentration (MIC) of DOX against V. parahaemolyticus. It was indicated that the time during which the DOX concentration in the hepatopancreas was above the MIC (T > MIC) was approximately 4 h, corresponding theoretically to an 8-hour dosing interval. However, this PK/PD interpretation is presented as supportive information and should be interpreted with caution. A depletion study was conducted by administering DOX-medicated feed once and twice daily for three consecutive days at the same dose. DOX residues in shrimp muscle dropped below the limit of detection after 14 days of stopping medication. Based on a maximum residue limit (MRL) of 50 µg/kg, the estimated withdrawal time at 26.5 °C ranged from 8 to 10 days, depending on the dosing regimen (once or twice a day). Regarding histological analysis, the effect of DOX on hepatopancreas was significant during the twice a day dosing treatment, but recovery of hepatopancreatic cells was observed within seven days after medication.

Human African trypanosomiasis, Chagas disease, and leishmaniasis are neglected, debilitating diseases caused by protozoa of the Trypanosomatidae family. In search of new effective therapies, subtle modifications of purine nucleosides have previously afforded agents that demonstrate promising activity against these protozoa, also in vivo. Here, a library of imidazo[2,1-f][1,2,4]triazine ribosides with varying substituents at C6 (trivial purine numbering) was synthesized through late-stage diversification of a common propyl thioether precursor and screened against a panel of the aforementioned Trypanosomatidae. While numerous analogues displayed selective antitrypanosomatid activity, an N 6,N 6-butylmethylamine analogue 58 proved exquisitely potent against L. infantum, T. cruzi, and T. brucei spp. This analogue was progressed to an acute Chagas and a bioluminescent visceral leishmaniasis mouse model with encouraging results.

Wild animals are increasingly exposed to a complex array of environmental stressors, including habitat fragmentation, pollution, and emerging infectious diseases, which can interact in unpredictable ways to influence animal health and survival. The European hedgehog (Erinaceus europaeus), recently classified as near threatened on the IUCN red list, faces many of these challenges. This study investigates the relationships between hepatic concentrations of metallic trace elements (MTEs) and health status in free-ranging Belgian hedgehogs, both juveniles and adults, with a focus on hedgehog diphtheric disease (HDD) and a novel circovirus. We analyzed liver samples for essential (zinc [Zn], copper [Cu]) and nonessential (lead [Pb], cadmium [Cd]) MTEs, comparing levels between healthy and affected individuals. Results showed generally moderate MTE levels (Cd: 2.88±4.27 mg/kg dry weight [dw]; Pb: 1.06±1.34 mg/kg dw; Cu: 31.53±39.01 mg/kg dw; Zn: 365.56±282.10 mg/kg dw) compared with other European populations, with the exception of markedly elevated hepatic Zn concentrations, particularly in adults (576.32±200.20 mg/kg dw). Notably, Zn levels were significantly higher in individuals affected by HDD, across both juvenile (P<0.001) and adult (P<0.01) age classes. Although high environmental Zn exposure may predispose hedgehogs to disease, elevated hepatic Zn could also reflect infection-driven redistribution due to inflammation and host immune responses. These findings align with broader evidence linking altered MTE profiles to disease processes in wildlife and suggest a complex, potentially bidirectional interaction between trace element homeostasis and infectious disease. This study highlights the importance of incorporating MTE dynamics into wildlife health surveillance, and suggests that Zn may serve as a potential indicator and mediator of disease in hedgehogs and other free-ranging species.

The study consisted of two experiments. First, a PK experiment was set up with a single oral dose at 20 mg/kg body weight, and second, a withdrawal time determination study, where the fish were fed once a day for 5 consecutive days at the same dosage. The DOX concentration in medicated feed, fish muscle, plasma, liver, and kidney was analysed by LC-MS/MS. Phoenix 8.1 and WT 1.4 software were used in the calculation for PK parameters and withdrawal time, respectively. DOX was absorbed quickly into plasma after oral medication with an absorption half-life T1/2abs of 0.12 h, reaching the Cmax (116 μg/L) at 1 h (Tmax). DOX distribution was highest in the kidney, followed by the liver and plasma. The high DOX concentration in the kidney and liver supports the possibility of using DOX to treat relevant bacterial infections in snakehead. In conclusion, DOX is rapidly absorbed in snakehead after oral medication, has a significant tissue distribution, followed by slow elimination. Finally, after feeding medicated feed for 5 consecutive days, the withdrawal times of DOX in composite muscle and skin samples of snakehead were 4 days and 6 days (at 28.5°C) according to the maximum residue limits set by the European Commission (100 μg/kg for bovine, porcine and poultry) and Japanese authority (50 μg/kg), respectively.

Ticks play a significant role in the transmission of various pathogens, impacting both human and animal health. Understanding the factors influencing tick feeding preferences is crucial for mitigating the risk of tick-borne diseases. This study investigates the blood preference of Ixodes ricinus nymphs, focusing on host species, stress hormone levels (glucocorticoids), and the presence of Borrelia burgdorferi s.l. bacteria. We conducted three series of in vitro experiments using a setup where individual blood drops (15 μl) were placed on filter paper over a 37 °C plate. Ticks were placed in the center, and their movements were tracked for 2 min to record preferences. The first experiment tested preferences for blood from different hosts (mouse, bird, sheep). The second examined the role of stress hormones by offering blood with varying levels of added cortisol and corticosterone (0, 10, 100, 1000 ng/ml). The third experiment investigated the potential influence of Borrelia infection, combined with elevated stress hormone levels, on blood preference. Our results show that I. ricinus nymphs preferred blood without added glucocorticoids and, in mice, blood with Borrelia infection. No clear preference for a specific host species was observed. These findings offer insights into how host physiological state may affect tick host selection, even though I. ricinus may not always have the opportunity to choose between hosts. Future studies should explore these interactions in more biologically relevant models to better understand the dynamics of tick attachment and feeding. Unraveling these mechanisms could aid in developing new strategies to control tick-borne diseases.

Weaning is one of the most challenging stages in a piglet's life, with multiple stressors contributing to poor gut health. For several years, zinc oxide (ZnO) was the preferred means of promoting a healthy gut and preventing post-weaning diarrhea (PWD). However, with the banning of its use at medicinal levels in the EU since 2022, alternatives are needed. Berberine (BBR), an isoquinoline alkaloid, has been used for centuries in Chinese medicine to treat diarrhea and has pharmacological properties that could make this molecule an attractive alternative to ZnO. The aim of this study was to investigate how berberine is metabolized in the intestinal tract and liver of weaned piglets; determine which metabolites are detected in intestinal contents and plasma; and whether a low dose can alter histomorphological parameters, short-chain fatty acid (SCFA) production, and gut microbiota composition. A total of 60 piglets weaned at 4 weeks were divided into two groups (Control and BBR), each consisting of six pens of five animals. After two weeks of feeding with a normal diet or a berberine-supplemented diet (30 mg berberine/kg feed), berberine and its metabolites were quantified in intestinal contents and plasma by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) on 12 animals per group (2 male piglets per pen). Moreover, villus length and crypt depth were measured in small-intestinal tissue, and 16S rRNA gene sequencing was performed to examine jejunal, cecal, and colonic gut microbiota composition. Our findings show that piglets metabolize berberine into phase I and II metabolites; however, a low dose does not affect their histomorphology, microbiota composition, or SCFA production.

Mycotoxin contamination is a global threat to food safety and human health, especially in regions facing food insecurity, such as Sub-Saharan Africa. This intervention study evaluates the effectiveness of nixtamalization, a traditional alkaline cooking method, in reducing mycotoxin levels in maize and corresponding urinary biomarkers of exposure. Forty adult healthy volunteers from an informal settlement in Kliptown, Soweto (South Africa), were randomly assigned to consume control maize or visibly moldy maize subjected to nixtamalization. Nixtamalization achieved a reduction in fumonisin B3 and deoxynivalenol (DON) to unquantifiable or undetectable levels in maize, while reducing fumonisin B1 (FB1), fumonisin B2, and zearalenone (ZEN) by 95%, 95%, and 89%, respectively. Aflatoxin B1 was unquantifiable before and eliminated after treatment. Biomarker analysis revealed that after consumption of either control or nixtamalized maize, urinary levels of FB1, ZEN, and its metabolites α- and β-zearalenol (α- and β-ZEL) did not show significant differences between groups (p > 0.05). DON and tenuazonic acid levels were not affected by the intervention (p > 0.05), with urinary detection frequencies remaining above 90%. These results demonstrate nixtamalization effectively lowers mycotoxin levels in maize, resulting in exposure levels comparable to control maize, and highlight human biomonitoring as a sensitive tool for evaluating food safety interventions.

This study aimed to develop and validate a high-throughput UHPLC-MS/MS method for quantifying cholecalciferol (VitD3) and metabolites calcidiol (25(OH)VitD3) and calcitriol (1,25(OH)2VitD3), in chicken serum, egg yolk and tissues. Sample preparation involved protein precipitation for serum and liquid extraction for egg yolk and tissues, followed by clean-up using Oasis (R) OstroTM or PRiME HLB. The method was validated in-house, demonstrating calibration range (lower limit of quantification (LLOQ) - 100 ng mL- 1 or ng g- 1, r >= 0.99), accuracy and precision within VICH GL49 acceptance criteria, and limits of detection (LOD) (serum: 0.05-2.86 ng mL- 1; liver, kidney and muscle: 0.18-0.34 ng g- 1; egg yolk and skin+fat: 0.23-0.42 ng g- 1). The LLOQ values for VitD3 and 25(OH)VitD3 (0.5-1 ng mL- 1 or ng g- 1) were sufficiently low to quantify these components in all tested matrices. The method's applicability was tested using samples from laying hens and broiler chickens in field trials. Results showed that feed supplementation with VitD3 increased VitD3 concentrations in serum and egg yolk but did not affect 25(OH)VitD3 levels. Conversely, supplementation with 25(OH)VitD3 increased only 25(OH)VitD3 concentrations. Supplementation with 1,25(OH)2VitD3 did not result in an increase in concentration. In tissue samples, highest concentrations of VitD3 and 25(OH)VitD3 were found in the liver, kidney, and skin+fat. This validated method is suitable for evaluating the VitD3 status in animal-derived foods and assessing the nutritional status and health of chickens.

The impact of commonly used anticoagulant rodenticides (ARs) on non-target wild animals is poorly understood. This study contributes to a better understanding of European hedgehog (Erinaceus europaeus) exposure to ARs, associated sublethal health effects, and the role of slugs (Deroceras and Lehmannia, important prey items) in AR transmission. Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS) was used to determine exposure levels to first- and second-generation anticoagulant rodenticides (FGARs and SGARs) in 128 free-ranging European hedgehogs and 120 slugs. Short-term health effects of AR exposure were examined by administering an oral subclinical brodifacoum dose (0.019 mg/kg) to domestic African pygmy hedgehogs (Atelerix albiventris) once a week for six consecutive weeks. All livers of wild hedgehogs tested positive for at least one AR compound, with a maximum concentration for brodifacoum reaching 6743 ng/g wet weight (ww). AR prevalence was significantly higher in slugs from residential areas (30 %), compared to agricultural (7 %; p = 0.0353), forest (3 %; p = 0.0211) and park (3 %, p = 0.0211) areas. This coincides with significantly higher AR concentrations in hedgehogs from areas with higher human population densities (p = 0.047). No direct positive correlation was found between AR levels and the occurrence of hedgehog diphtheric disease (HDD), an often fatal ulcerative bacterial infection in hedgehogs, likely driven by multiple factors. Histopathological examination revealed hemorrhages in the renal medulla in two out of nine laboratory-exposed hedgehogs, suggesting sublethal effects after short-term AR exposure. The omnipresence of subclinical AR concentrations in wild hedgehogs and notably higher AR prevalence in slugs in densely populated areas, urge to explore long-term and ecosystem effects of widespread AR use.

The mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME), produced by Alternaria spp . , are common contaminants of food and feed and are a potential threat to animal and human health. To date, the most prominent data gaps for their comprehensive risk assessment concern information on their in vivo absorption, distribution, metabolism and excretion (ADME) and toxicokinetic behavior. The aim of this study was to determine the absolute oral bioavailability, quantitative toxicokinetic characteristics and biotransformation of AOH and AME in vivo in pigs, using crossover trials with intravenous and oral administration of a single dose of both mycotoxins at 2 mg/kg b.w. Plasma profiles of the mycotoxins and phase I and II metabolites were studied in the vena jugularis using UPLC-MS/MS and LC-HRMS methods. Furthermore, plasma from the vena portae was analyzed to study presystemic biotransformation. Urine was collected to determine the urinary excretion and metabolite profiles. Results reveal a low absolute oral bioavailability of AOH (15%) and AME (9%), caused by a low absorption and/or extensive first-pass biotransformation in the liver to mainly phase II, and to a lesser extent phase I metabolites. Quantitative toxicokinetic modeling of the IV data showed a high total body clearance for both AOH and AME (12.9 and 16.8 L/(h*kg b.w.), respectively), a high volume of distribution (4.97 and 5.15 L/kg b.w., respectively) and a short elimination half-life of 0.16 and 0.21 h, respectively. These findings may contribute to the risk assessment of AOH and AME and to the development of candidate biomarkers of exposure in biomonitoring studies since pigs are considered a suitable animal model to extrapolate to humans.

Mycotoxins, produced by fungi, contaminate animal feed and subsequently enter food products like eggs, posing significant health risks. This study aimed to optimize and validate a sensitive, cost-efficient, high-throughput UHPLC-MS/MS method for the qualitative analysis of 38 mycotoxins, and the quantification of 30, 29 and 29 regulated and emerging mycotoxins in chicken serum, egg yolk and egg white, respectively. Sample preparation involved liquid extraction with 0.1

Florfenicol (FF) is one of the common antimicrobials used to control bacterial disease in shrimp aquaculture. This study aimed to determine the pharmacokinetics (PK) parameters of FF in white leg shrimp plasma, hepatopancreas and muscle as well as its residue depletion in shrimp muscle and the impact on shrimp hepatopancreas histology during and after FF medication. In the PK experiment, shrimp were fed once at 10 mg FF/kg body weight (bw) via oral in-feed administration to determine PK parameters in plasma, hepatopancreas and muscle. The maximum concentration (Cmax) of 60.56 μg/L in plasma was observed after 1.77 h (Tmax). In muscle, a Cmax of 11.76 μg/kg was attained after 0.20 h, while in hepatopancreas, the Cmax was higher (386.92 μg/kg) and was rapidly obtained (Tmax = 0.19 h). The Cmax values in shrimp plasma were below the minimum inhibitory concentration (MIC) against Vibrio parahaemolyticus, known to cause acute hepatopancreatic necrosis disease (AHPND) in shrimp. Therefore, it can be concluded that to ensure the effectiveness of this treatment, the dose should be higher than 10 mg FF/kg bw. FF depletion in white leg shrimp muscle and its histological impact on hepatopancreas were determined after feeding FF-medicated feed once-a-day or twice-a-day for 3 consecutive days with a dose of 10 mg FF/kg bw. The residues in shrimp muscle were rapidly eliminated and fell below the limit of quantification at 24 h after stopping medication. The withdrawal time of FF in shrimp muscle was 27.9 degree-days (2 days at 26.5 °C) according to the maximum residue limit (MRL) of 100 µg/kg set by the European Commission and Korean Ministry and when feeding FF twice-a-day for 3 days. The results from histological analysis showed that there was no negative effect on shrimp hepatopancreas after stopping medication in both once- and twice-a-day treatments.

Plasticity of skeletal muscle is induced by transcriptional and translational events in response to exercise, leading to multiple health and performance benefits. The skeletal muscle microenvironment harbors myofibers and mononuclear cells, but the rich cell diversity has been largely ignored in relation to exercise adaptations. Using our workflow of transcriptome profiling of individual myofibers, we observed that their exercise-induced transcriptional response was surprisingly modest compared with the bulk muscle tissue response. Through the integration of single-cell data, we identified a small mast cell population likely responsible for histamine secretion during exercise and for targeting myeloid and vascular cells rather than myofibers. We demonstrated through histamine H1 or H2 receptor blockade in humans that this paracrine histamine signaling cascade drives muscle glycogen resynthesis and coordinates the transcriptional exercise response. Altogether, our cellular deconstruction of the human skeletal muscle microenvironment uncovers a histamine-driven intercellular communication network steering muscle recovery and adaptation to exercise.

Journal of Veterinary Pharmacology and TherapeuticsEarly View OBITUARY Patrick De Backer—Obituary Siska Croubels, Corresponding Author Siska Croubels [email protected] Ghent University, Belgium Correspondence: Mathias Devreese ([email protected]) Siska Croubels ([email protected])Search for more papers by this authorMathias Devreese, Corresponding Author Mathias Devreese [email protected] Ghent University, Belgium Correspondence: Mathias Devreese ([email protected]) Siska Croubels ([email protected])Search for more papers by this author Siska Croubels, Corresponding Author Siska Croubels [email protected] Ghent University, Belgium Correspondence: Mathias Devreese ([email protected]) Siska Croubels ([email protected])Search for more papers by this authorMathias Devreese, Corresponding Author Mathias Devreese [email protected] Ghent University, Belgium Correspondence: Mathias Devreese ([email protected]) Siska Croubels ([email protected])Search for more papers by this author First published: 16 February 2025 https://doi.org/10.1111/jvp.13501Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookxLinkedInRedditWechat No abstract is available for this article. Early ViewOnline Version of Record before inclusion in an issue RelatedInformation

This meta-analysis provides a population model of doxycycline (DOXY) disposition in pigs for computation of PK/PD cutoff values corresponding to differing modalities of DOXY administration orally in pigs. This analysis enables establishment of specific clinical breakpoints for the development of antimicrobial susceptibility testing of DOXY in pigs. The meta-analysis of 380 data sets, totaling 3295 plasma concentrations obtained from 300 pigs weighing 8.5-101 kg, was performed using a non-linear mixed effect model. The plasma clearance for a typical 50 kg BW pig was estimated to be 0.259 L/kg/h with a corresponding plasma half-life of 7.33 h. The bioavailability of DOXY administered in feed under field conditions was estimated to be 50%, with a large between-subject variability of 84.8%. The bioavailability of DOXY in solution in drinking water was significantly lower (30.7%) but much less variable, with a between-subject variability of 34.3%. Several dosing schedules (5 to 20 mg/kg per day) for two administration modalities (drinking water vs. food) were simulated to calculate the corresponding PK/PD cutoffs. The highest PK/PD cutoff of 0.50 mg/L was obtained for DOXY administered in feed at 20 mg/kg BW.

In 2023, the slaughterhouse-sampled meat and liver of some cows from Belgian businesses were found not to comply with the maximum levels for PFOS described in European legislation. These post-mortem results led to a ban on the entry into the food chain of food obtained from animals coming from the affected businesses. The Federal Agency for the Safety of the Food Chain (FASFC) wishes to propose tools to livestock farmers to enable them to manage PFAS contamination and take the best possible decisions and this within the framework of their self-checking system. Therefore, the Scientific Committee (SciCom) established at the FASFC assessed the possibility of establishing a guide value for PFAS compounds in bovine blood to estimate whether PFAS levels in meat, liver and kidney comply with the European maximum levels (Regulation (EU) 2023/915). To this end, the SciCom relied on (i) Danish Decree No 1386 of 29/11/2023, (ii) literature data and (iii) monitoring data from the FASFC. In addition, a linear regression analysis was applied to data of PFOS concentrations in blood plasma and muscle tissue from the same animals (paired results for 28 cows) (Johnston et al. , 2023). This analysis performed on a logarithmic transformation of the raw data allowed to determine that a PFOS content of 0.3 μg/kg in meat (= legal European maximum content) corresponds to a most probable PFOS content of 6.2 μg/L in the blood plasma with a 95% confidence interval of 2.5 to 23.4 μg/L. For liver and kidney, it was not possible to apply this type of approach due to the lack of available paired data (PFOS content in blood and tissues from the same animal). The obtained lower limit of 2.5 μg/L is close to, but more conservative, than the guide value of 3.3 μg PFOS/L blood plasma applied by the Danish authorities. The SciCom considers that a PFOS level of 2.5 μg/L blood plasma is an appropriate guide value to estimate a compliance of a PFOS level in the meat, liver and kidney. For PFOA, PFHxS and PFNA, there is less to no data to derive such a guide value in blood plasma. Based on the available data, the SciCom considers that the same concentration of 2.5 μg/L blood plasma can also be applied to estimate a compliance of levels of PFOA, PFHxS or PFNA in bovine meat, liver and kidney. It should be stressed that this guide value of 2.5 μg/L is subject to significant uncertainties. Ratios between PFAS levels in bovine muscle tissue, liver and kidney were assessed using (i) FASFC control data and (ii) data from the scientific literature. The aim was to assess whether the liver or kidneys of a slaughtered bovine should be destroyed if the meat is non-compliant or vice versa. On the basis of available results for the liver (n = 16), it could be determined that the PFOS concentration in the liver is between 6 and 34 times higher (on average 21 times) than that in muscle tissue, while the PFOS concentration in the kidneys (n = 8) is between 3 and 12 times higher (on average 8 times) than that in muscle tissue. No such ratio could be derived for PFOA, PFNA and PFHxS due to insufficient data. It is noted that these ratios for PFOS were determined from a relatively limited number of data from different studies with differences in experimental design, and that no distinction was made between breed, sex and lactation status of the cattle when deriving the ratios. Finally, the SciCom evaluated the possibility of determining, based on ante-mortem blood analysis, a withdrawal time after which bovine muscle tissue, liver and kidney will be compliant for PFAS after removal of the source of contamination. For this purpose, literature sources regarding the depletion kinetics of PFAS in bovine blood were reviewed. For PFOS, elimination half-lives in blood of 39 (lactating cow) to 120 days (steer) were distinguished. For PFOA, elimination half-lives in blood were 1.3 (lactating cow) and 19.2 days (steers). For PFNA the elimination half-lives in blood were 8.7 (lactating cow) and 12.3 days (beef cattle), and for PFHxS the half-life was 9.3 days for beef cattle. Chou et al. (2023) implemented a physiological-based pharmacokinetic (PBPK) model implemented in an interactive generic platform publicly accessible via the internet where tissue withdrawal times for PFOA, PFOS and PFHxS can be calculated for beef cattle and dairy cows. This platform could be used to predict withdrawal times for these PFAS in beef cattle and dairy cows. An important limitation of the platform is that several parameter values need to be known to enter into the application, in particular the number of animals, PFAS concentration in soil or water, time interval of dosing of PFAS contamination, exposure frequency and exposure duration. It will often prove difficult if not impossible for a livestock farmer to know or determine these values. In addition, the source of contamination may be different, it could be, for example, contaminated feed, and not soil or water. In addition, scientific publications report other equations that would approximate depletion kinetics in blood plasma or blood serum (Johnston et al. , 2023; Mikkonen et al. , 2023), but also these turn out to be of little use in practice because of the required parameters that need to be known and the complexity. Therefore, the working group itself developed a pragmatic approach for calculating a withdrawal time after which a second blood sample should be collected and analysed, in case of an initial blood test indicating an excess PFAS level. The equation for calculating such a withdrawal time (see recommendations below) contains as constants the target value for PFAS in blood plasma of 2.5 μg/L and an elimination half-life for PFAS (for which a value from literature should be selected). Therefore, such a calculated withdrawal time is subject to significant uncertainties. When a contamination by PFAS is detected on a farm, it is recommended to identify and eliminate the source of contamination (e.g. water, soil or feed) or to prevent animals from having access to it. The SciCom recommends the threshold value of 2.5 μg/L of bovine blood plasma as a suitable guide value to estimate ante-mortem a compliance against the legal European maximum levels of PFOS, PFOA, PFHxS or PFNA in the meat, liver and kidney. As discussed above, this guide value of 2.5 μg/L is subject to significant uncertainties. The SciCom emphasises that it cannot be excluded that possible non-compliant results of PFAS may be observed in the meat, liver or kidney of cattle following a blood test complying with the 2.5 μg/L guide value. The SciCom therefore recommends assessing in the near future the number of cases in which a level of PFOS, PFOA, PFHxS or PFNA in blood plasma not exceeding the guide value of 2.5 μg/L is actually related to meat, kidney and liver conformity for these 4 PFAS. It is therefore recommended to determine and to collect paired data (from the same animal) concerning PFAS in the blood plasma, muscle tissue, liver and kidney of bovines originating from businesses affected by a PFAS contamination. These additional data can then serve as a basis for confirming or, if necessary, adjusting the guide value of 2.5 μg/L. If an analysis of a bovine blood plasma would show that the concentration of PFOS, PFOA, PFHxS or PFNA is higher than the guide value of 2.5 μg/L, then it is recommended to perform another blood plasma analysis at a later date until a result lower than this value is obtained. This later data can be calculated using the following equation: Equation of the withdrawal time (t, in days) in blood plasma/serum to obtain the targeted guide value, where C 0 represents the starting concentration (μg/L) of PFOS, PFOA, PFHxS or PFNA in the blood plasma/serum, i.e. the concentration measured at initial sampling; 2,5 μg/L the suggested blood plasma/serum concentration guide value; DT 50 the blood plasma/serum elimination half-life of PFOS, PFOA, PFHxS or PFNA (days). Here, the SciCom also refers to the uncertainties discussed above. The withdrawal time should therefore be considered as an indication to determine a time when a second blood test may be useful. However, it cannot be excluded that after the estimated withdrawal time a bovine would still show a PFAS level in blood plasma higher than 2.5 μg/L. In addition, calculated withdrawal times are expected to be rather long based on the relatively long elimination half-lives of PFAS described in the literature. For these reasons, the practical usefulness of these withdrawal times is rather low. In addition, for PFOS, it is recommended to use the following ratios to estimate its relative concentration in bovine muscle tissue, liver or kidney without having to carry out separate measurements in all these tissues: the PFOS concentration in liver is on average 21 times (between 6 and 34 times) higher than that in muscle tissue, while the PFOS concentration in kidney is on average 8 times (between 3 and 12 times) higher than that in muscle tissue. Significant uncertainties are applicable to these ratios. The SciCom recommends sampling paired samples (from the same animal) of muscle tissue, liver and kidney from Belgian bovines in the near future to verify these PFOS ratios between the different animal tissues.

Abstract Background Serum symmetric dimethylarginine (SDMA) is used to screen for renal dysfunction in dogs. The gold standard technique for measuring SDMA, liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) is not widely available. Age‐specific reference intervals for SDMA in older dogs are lacking. Objectives Prospective study in older dogs to validate a commercially available LC‐MS/MS method for SDMA, compare SDMA concentrations with concentrations measured using ELISA and obtain a reference interval (RI) for older dogs using both methods. Animals Client‐owned older dogs undergoing health screening. Methods The LC‐MS/MS method was analytically validated (limit of detection, precision, and linearity). Serum was sent cooled overnight for ELISA or was frozen at −80°C until batch analysis using LC‐MS/MS. Results of LC‐MS/MS and ELISA were compared and RIs for older dogs were calculated according to international guidelines. Results The LC‐MS/MS method showed good linearity (r2 = .99) and precision (coefficient of variation <10%), with a laboratory RI between 8.0 and 14.0 μg/dL. Paired measurements were available from 118 different dogs. Median SDMA concentration were 9.4 (range, 5.0‐21.2) using LC‐MS/MS and 12.0 (range, 5.0‐22.0) μg/dL using ELISA. Both methods significantly differed with a mean difference of 2.2 μg/dL. The RI for older dogs for LC‐MS/MS was 4.4‐15.0 μg/dL, and for ELISA was 6.4‐17.4 μg/dL. Conclusions and Clinical Importance The ELISA provided significantly higher SDMA concentrations compared to the validated LC‐MS/MS method, indicating the need for device‐ or assay‐specific RI. The obtained age‐specific RI for SDMA is considerably higher in older dogs compared to the general laboratory RI.

This study examined the effects of fumonisins (FBs) and aflatoxin B1 (AFB1), alone or in combination, on the productivity and health of laying hens, as well as the transfer of aflatoxins (AFs) to chicken food products. The efficacy and safety of mycotoxin detoxifiers (bentonite and fumonisin esterase) to mitigate these effects were also assessed. Laying hens (400) were divided into 20 groups and fed a control, moderate (54.6 µg/kg feed) or high (546 µg/kg feed) AFB1 or FBs (7.9 mg/kg feed) added diets, either alone or in combination, with the mycotoxin detoxifiers added in selected diets. Productivity was evaluated by feed intake, egg weight, egg production, and feed conversion ratio whereas health was assessed by organ weights, blood biochemistry, and mortality. Aflatoxins residues in plasma, liver, muscle, and eggs were determined using UHPLC-MS/MS methods. A diet with AFB1 at a concentration of 546 µg/kg feed decreased egg production and various AFB1-contaminated diets increased serum uric acid levels and weights of liver, spleen, heart, and gizzard. Interactions between AFB1 and FBs significantly impacted spleen, heart, and gizzard weights as well as AFB1 residues in eggs. Maximum AFB1 residues of 0.64 µg/kg and aflatoxin M1 (below limits of quantification) were observed in liver, plasma, and eggs of layers fed diets with AFB1. The mycotoxin detoxifiers reduced effects of AFB1 and FBs on egg production, organ weights, blood biochemistry, and AFB1 residues in tissues. This study highlights the importance of mycotoxin detoxifiers as a mitigation strategy against mycotoxins in poultry production.

Sepsis remains a huge unmet medical need for which no approved drugs, besides antibiotics, are on the market. Despite the clinical impact of sepsis, its molecular mechanism remains inadequately understood. Recent insights have shown that profound hepatic transcriptional reprogramming, leading to fatal metabolic abnormalities, might open a new avenue to treat sepsis. Translation of experimental results from rodents to larger animal models of higher relevance for human physiology, such as pigs, is critical and needs exploration. We performed a comparative analysis of the transcriptome profiles in murine and porcine livers using the following sepsis models: cecal ligation and puncture (CLP) in mice and fecal instillation (FI) in pigs, both of which induce polymicrobial septic peritonitis, and lipopolysaccharide (LPS)-induced endotoxemia in pigs, inducing sterile inflammation. Using bulk RNA sequencing, Metascape pathway analysis, and HOMER transcription factor motif analysis, we were able to identify key genes and pathways affected in septic livers. Conserved upregulated pathways in murine CLP and porcine LPS and FI generally comprise typical inflammatory pathways, except for ER stress, which was only found in the murine CLP model. Conserved pathways downregulated in sepsis comprise almost exclusively metabolic pathways such as monocarboxylic acid, steroid, biological oxidation, and small-molecule catabolism. Even though the upregulated inflammatory pathways were equally induced in the two porcine models, the porcine FI model more closely resembles the metabolic dysfunction observed in the CLP liver compared to the porcine LPS model. This comprehensive comparison focusing on the hepatic responses in mouse CLP versus LPS or FI in pigs shows that the two porcine sepsis models generally resemble quite well the mouse CLP model, with a typical inflammatory signature amongst the upregulated genes and metabolic dysfunction amongst the downregulated genes. The hepatic ER stress observed in the murine model could not be replicated in the porcine models. When studying metabolic dysfunction in the liver upon sepsis, the porcine FI model more closely resembles the mouse CLP model compared to the porcine LPS model.