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The 'developmental origins of health and disease' hypothesis proposes not only that we are what we eat, but also that we could be what our parents ate. Here, we aimed to improve health and performance of young piglets via maternal diets based on the hypothesis that maternal nutritional interventions change metabolic programming in piglets, reflected by differential gene expression early in life. Therefore, sows were fed either a regular diet, based on barley, wheat and wheat by-products, sugar beet pulp, palm oil and oilseed meal, or a high-fat ( HF) diet consisting of the regular diet supplemented with an additional amount of 3.5% soybean oil and 1% fish oil at the expense of palm oil and wheat. Performance results, physiological parameters and gene expression in liver of piglets and blood of piglets and sows at day 7 after farrowing from both diet groups were compared. The HF diet tended to enhance growth rate of the offspring in the first week of life. No significant differences in gene expression in liver tissue and blood could be detected between the two groups, neither with whole-genome microarray analysis, nor with gene specific qPCR analysis. In this study, the feeding of a high-fat diet with increased amounts of polyunsaturated fatty acid ( PUFA) to gestating sows under practical farm settings did not induce significant changes in gene expression in sows and offspring. [ABSTRACT FROM AUTHOR]

Background: Bovine paratuberculosis is a devastating infectious disease caused by Mycobacterium avium subsp. paratuberculosis (MAP). The development of the paratuberculosis in cattle can take up to a few years and vastly differs between individuals in severity of the clinical symptoms and shedding of the pathogen. Timely identification of high shedding animals is essential for paratuberculosis control and minimization of economic losses. Widely used methods for detection and quantification of MAP, such as culturing and PCR based techniques rely on direct presence of the pathogen in a sample and have little to no predictive value concerning the disease development. In the current study, we investigated the possibility of predicting MAP shedding severity in cattle based on the faecal microbiota composition. Twenty calves were experimentally infected with MAP and faecal samples were collected biweekly up to four years of age. All collected samples were subjected to culturing on selective media to obtain data about shedding severity. Faecal microbiota was profiled in a subset of samples (n = 264). Using faecal microbiota composition and shedding intensity data a random forest classifier was built for prediction of the shedding status of the individual animals., Results: The results indicate that machine learning approaches applied to microbial composition can be used to classify cows into groups by severity of MAP shedding. The classification accuracy correlates with the age of the animals and use of samples from older individuals resulted in a higher classification precision. The classification model based on samples from the first 12 months of life showed an AUC between 0.78 and 0.79 (95% CI), while the model based on samples from animals older than 24 months showed an AUC between 0.91 and 0.92 (95% CI). Prediction for samples from animals between 12 and 24 month of age showed intermediate accuracy [AUC between 0.86 and 0.87 (95% CI)]. In addition, the results indicate that a limited number of microbial taxa were important for classification and could be considered as biomarkers., Conclusions: The study provides evidence for the link between microbiota composition and severity of MAP infection and shedding, as well as lays ground for the development of predictive diagnostic tools based on the faecal microbiota composition., (© 2021. The Author(s).)

In assessing species susceptibility for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and in the search for an appropriate animal model, multiple research groups around the world inoculated a broad range of animal species using various SARS-CoV-2 strains, doses and administration routes. Although in silico analyses based on receptor binding and diverse in vitro cell cultures were valuable, exact prediction of species susceptibility based on these tools proved challenging. Here, we assessed whether precision-cut lung slices (PCLS) could facilitate the selection of animal models, thereby reducing animal experimentation. Pig, hamster and cat PCLS were incubated with SARS-CoV-2 and virus replication was followed over time. Virus replicated efficiently in PCLS from hamsters and cats, while no evidence of replication was obtained for pig PCLS. These data corroborate the findings of many research groups that have investigated the susceptibility of hamsters, pigs and cats towards infection with SARS-CoV-2. Our findings suggest that PCLS can be used as convenient tool for the screening of different animal species for sensitivity to newly emerged viruses. To validate our results obtained in PCLS, we employed the hamster model. Hamsters were inoculated with SARS-CoV-2 via the intranasal route. Susceptibility to infection was evaluated by body weight loss, viral loads in oropharyngeal swabs and respiratory tissues and lung pathology. The broadly used hamster model was further refined by including activity tracking of the hamsters by an activity wheel as a very robust and sensitive parameter for clinical health. In addition, to facilitate the quantification of pathology in the lungs, we devised a semi-quantitative scoring system for evaluating the degree of histological changes in the lungs. The inclusion of these additional parameters refined and enriched the hamster model, allowing for the generation of more data from a single experiment.

Background: Gene expression profiles of intestinal mucosa of chickens and pigs fed over long-term periods (days/weeks) with a diet rich in rye and a diet supplemented with zinc, respectively, or of chickens after a one-day amoxicillin treatment of chickens, were recorded recently. Such dietary interventions are frequently used to modulate animal performance or therapeutically for monogastric livestock. In this study, changes in gene expression induced by these three interventions in cultured "Intestinal Porcine Epithelial Cells" (IPEC-J2) recorded after a short-term period of 2 and 6 hours, were compared to the in vivo gene expression profiles in order to evaluate the capability of this in vitro bioassay in predicting in vivo responses., Methods: Lists of response genes were analysed with bioinformatics programs to identify common biological pathways induced in vivo as well as in vitro. Furthermore, overlapping genes and pathways were evaluated for possible involvement in the biological processes induced in vivo by datamining and consulting literature., Results: For all three interventions, only a limited number of identical genes and a few common biological processes/pathways were found to be affected by the respective interventions. However, several enterocyte-specific regulatory and secreted effector proteins that responded in vitro could be related to processes regulated in vivo, i.e. processes related to mineral absorption, (epithelial) cell adherence and tight junction formation for zinc, microtubule and cytoskeleton integrity for amoxicillin, and cell-cycle progression and mucus production for rye., Conclusions: Short-term gene expression responses to dietary interventions as measured in the in vitro bioassay have a low predictability for long-term responses as measured in the intestinal mucosa in vivo. The short-term responses of a set regulatory and effector genes, as measured in this bioassay, however, provided additional insight into how specific processes in piglets and broilers may be modulated by "early" signalling molecules produced by enterocytes. The relevance of this set of regulatory/effector genes and cognate biological processes for zinc deficiency and supplementation, gluten allergy (rye), and amoxicillin administration in humans is discussed.

A novel orthobunyavirus, named "Schmallenberg virus" (SBV), was first detected in the blood of cattle at the end of the summer in Germany in 2011, and subsequently in late autumn from the brain of a stillborn malformed lamb in The Netherlands. Full genome sequences, including 5' and 3' terminal "panhandle" sequences of the L, M, and S segments of the SBV isolated from lamb brain tissue (named HL1) were determined. In addition, a second SBV strain was isolated from the blood of a dairy cow (named F6) also in The Netherlands. This isolate was passaged on Vero cells, and its genome sequence was determined by next-generation sequencing. Alignments of the two genome sequences revealed 4, 12, and 2 amino acid differences in the open reading frames of the L, M, and S segments, respectively. Eleven of a total of 12 amino acid differences were detected in the M segment encoding the ectodomain of the putative structural glycoprotein Gc. Notably, in the HL1 isolate, positions 737-739 are occupied by isoleucine, arginine, and leucine (IRL), whereas in the majority of other sequenced SBV isolates these positions are occupied by threonine, histidine, and proline, respectively. Moreover, in all sheep, goat, and cattle SBV isolates sequenced and published so far, an IRL sequence was never found. This has brought us to the conclusion that the M segment of the HL1 isolate differed markedly from that of other lamb and cow isolates. Whether this atypical variant resulted from adaptation to the ewe, fetus, or insect vector remains to be investigated.

Background: The aim of this study was to identify transcription factors/regulators that play a crucial role in steering the (innate) immune response shortly (within a few hours) after the first contact of the intestinal mucosa with an inflammatory mediator, and to test whether the processes regulated by these factors/regulators can be modulated by chemical substances of natural origin., Methods: We experimentally induced inflammation by perfusion of surgically applied jejunal loops with Salmonella enterica subspecies enterica serovar Typhimurium DT104 in three pigs. Segments of mock and Salmonella treated loops were dissected after 2, 4 and 8 hours of perfusion. IL8 and IL1-beta mRNA expression levels were measured in mucosal scrapings of all segments. Furthermore, intra-animal microarray comparisons (isogenic) between Salmonella and mock treated segments after 8 hours, and inter-animal comparisons between similar Salmonella-treated loops of each pig at 2 and 4 hours, were performed., Results: IL-1beta and IL8 mRNA levels, and intra-animal microarray comparisons at 8 hours between Salmonella and mock treated segments showed that the response-time and type of response to Salmonella was different in all three pigs. This plasticity allowed us to extract a comprehensive set of differentially expressed genes from inter-animal comparisons at 2 and 4 hours. Pathway analysis indicated that many of these genes play a role in induction and/or tempering the inflammatory response in the intestine. Among them a set of transcription factors/regulators known to be involved in regulation of inflammation, but also factors/regulators for which involvement was not expected. Nine out of twenty compounds of natural origin, which according to literature had the potential to modulate the activity of these factors/regulators, were able to stimulate or inhibit a Salmonella-induced mRNA response of inflammatory-reporter genes IL8 and/or nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha in cultured intestinal porcine epithelial cells., Conclusions: We describe a set of transcription factors/regulators possibly involved in regulation of "very early" immune mechanism which determines the inflammatory status of the intestine later on. In addition, we show that these mechanisms may be modulated by chemical substances of natural origin.