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Motion is a crucial part of the natural world, yet our understanding of how animals avoid predation whilst moving remains rather limited. Although several theories have been proposed for how antipredator defence may be facilitated during motion, there is often a lack of supporting empirical evidence, or conflicting findings. Furthermore, many studies have shown that motion often 'breaks' camouflage, as sudden movement can be detected even before an individual is recognised. Whilst some static camouflage strategies may conceal moving animals to a certain extent, more emphasis should be given to other modes of camouflage and related defences in the context of motion (e.g. flicker fusion camouflage, active motion camouflage, motion dazzle, and protean motion). Furthermore, when motion is involved, defence strategies are not necessarily limited to concealment. An animal can also rely on motion to mislead predators with regards to its trajectory, location, size, colour pattern, or even identity. In this review, we discuss the various underlying antipredator strategies and the mechanisms through which they may be linked to motion, conceptualising existing empirical and theoretical studies from two perspectives – concealing and misleading effects. We also highlight gaps in our understanding of these antipredator strategies, and suggest possible methodologies for experimental designs/test subjects (i.e. prey and/or predators) and future research directions. [ABSTRACT FROM AUTHOR]

Background: Medium-chain triglycerides such as decanoic acid (C10), which is one of the fatty acids that constitute dietary fats, are of substantial interest for their potential therapeutic effects on neuropsychiatric disorders. However, the effects of C10 on attentiondeficit/hyperactivity disorder (ADHD) remain to be studied. We explored the effects of C10 on behavioural activity and antioxidant defences in an experimental animal model of ADHD. Methods: To establish an experimental animal model of ADHD, neonatal rats were subjected to unilateral striatal lesions using 6-hydroxydopamine (6-OHDA). The rats sequentially underwent open-field and Y-maze tests before treatment [postnatal day 25 (PN25)]. After the subcutaneous administration of either vehicle or C10 solution (250 mg/kg) for 14 days, the behavioural tests were repeated on PN39. Next, we examined the effects of C10 on the expression of the constitutive antioxidant enzymes catalase and glutathione peroxidase-1/2 and the phase II transcription factor nuclear factor erythroid 2-related factor 2 in four different regions of the rat brain. Results: Injection of 6-OHDA unilaterally into the striatum resulted in elevated locomotor activity on PN39. The administration of C10 for a period of 14 days did not alter the locomotor hyperactivity. Moreover, the administration of C10 had no significant effects on the expression of proteins related to antioxidant defences in the hippocampus, prefrontal cortex, striatum or cerebellum of both control and lesioned rats. Conclusions: The lack of significant effects of C10 in our study may depend on the dose and duration of C10 administration. Further exhaustive studies are needed to verify the efficacy and effects of different doses and treatment durations of C10 and to explore the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Tetrodotoxin (TTX) is a neurotoxic molecule used by many animals for defense and/or predation, as well as an important biomedical tool. Its ubiquity as a defensive agent has led to repeated independent evolution of tetrodotoxin resistance in animals. TTX binds to voltage-gated sodium channels (VGSC) consisting of α and β subunits. Virtually all studies investigating the mechanisms behind TTX resistance have focused on the α subunit of voltage-gated sodium channels, where tetrodotoxin binds. However, the possibility of β subunits also contributing to tetrodotoxin resistance was never explored, though these subunits act in concert. In this study, we present preliminary evidence suggesting a potential role of β subunits in the evolution of TTX resistance. We gathered mRNA sequences for all β subunit types found in vertebrates across 12 species (three TTX-resistant and nine TTX-sensitive) and tested for signatures of positive selection with a maximum likelihood approach. Our results revealed several sites experiencing positive selection in TTX-resistant taxa, though none were exclusive to those species in subunit β1, which forms a complex with the main physiological target of TTX (VGSC Nav1.4). While experimental data validating these findings would be necessary, this work suggests that deeper investigation into β subunits as potential players in tetrodotoxin resistance may be worthwhile. [ABSTRACT FROM AUTHOR]

Predator–prey interactions have been suggested as drivers of diversity in different lineages, and the presence of anti-predator defences in some clades is linked to higher rates of diversification. Warning signals are some of the most widespread defences in the animal world, and there is evidence of higher diversification rates in aposematic lineages. The mechanisms behind such species richness, however, are still unclear. Here, we test whether lineages that use aposematism as anti-predator defence exhibit higher levels of genetic differentiation between populations, leading to increased opportunities for divergence. We collated from the literature more than 3000 pairwise genetic differentiation values across more than 700 populations from over 60 amphibian species. We find evidence that over short geographical distances, populations of species of aposematic lineages exhibit greater genetic divergence relative to species that are not aposematic. Our results support a scenario where the use of warning signals could restrict gene flow, and suggest that anti-predator defences could impact divergence between populations and potentially have effects at a macro-evolutionary scale. [ABSTRACT FROM AUTHOR]

Simple Summary: Modern sows have an elevated metabolic rate, which can result in oxidative stress and impair reproductive performance. From this study, it is clear that dietary supplementation of beta-carotene can mitigate oxidative damage during lactation and increase piglet weight at weaning. When used from the beginning of gestation, beta-carotene supplementation also results in a greater number of weaned piglets and higher weaning weight. The rapid fetal development and the increased demand for milk result in a catabolic state and oxidative stress in hyperprolific sows. Despite animal defense mechanisms, the dietary supplementation of antioxidants is being evaluated to reduce the impacts of excess free radicals. The aim of this study was to evaluate the short- and long-term effects of beta-carotene supplementation for sows on the reproductive response and performance of suckling piglets. A total of 120 sows were distributed in a 3 × 4 factorial arrangement of three supplementation levels (B0–no supplementation, B200–200 mg beta-carotene/day and B400–400 mg beta-carotene/day) and four groups of parity order (1st, 2nd, 3rd, above 4th). Beta-carotene supplementation during lactation resulted in a higher litter weight at weaning. A higher average weight of piglets and litter weight at birth were observed, as well as a greater number of piglets weaned and litter weight at weaning in sows supplemented with 400 mg of beta-carotene during gestation and lactation periods. Supplementation with 200 and 400 mg of beta-carotene resulted in a greater weight at weaning and daily weight gain in piglets. Daily supplementation with 400 mg of beta-carotene in the prepartum and lactation phases provides a greater litter weight at weaning and, when supplemented in the pre-gestation and gestation periods, results in a greater litter weight at birth and at weaning. [ABSTRACT FROM AUTHOR]

All jawed vertebrates have four T cell receptor (TCR) chains expressed by thymus-derived lymphocytes that play a significant role in animal immune defense. However, avian TCR studies have been limited to a few species, although their co-functional major histocompatibility complexes (MHCs) have been studied for decades, showing various copy numbers and polymorphisms. Here, using public genome data, we characterized the copy numbers, the phylogenic relationship and selection of T cell receptor complex (TCR-C) segments, and the genomic organization of TCR loci across birds. Various numbers of C segments were found in the TCRα/TCRδ, TCRβ, and TCRγ loci, and phylogenetic analysis reflected both ancient gene duplication events (two Cβ segments and Cδ segments divergent into CδI and CδII) and contemporary evolution (lineage-specific and species-specific characteristics). Most passerines lack CδII segments and a second TRD locus, except Meliphagidae and Maluridae. A relatively stable structure was verified in four TCR loci of birds, except for the arrangement of V segment groups. In this study, we explored the phylogenetic relationships of TCR-C segments across avians for the first time. We inferred gene duplication and loss events during the evolution process. The finding of diverse TCR germline repertoires provides a better understanding of the immune systems of birds. [ABSTRACT FROM AUTHOR]

Protective defense mechanisms are well documented across the animal kingdom, but there are still examples of antipredator defenses that do not fit easily into the current conceptualization. They either fall within the intersection of multiple mechanisms or fail to fall neatly into pre‐existing categories. Here, using Endler's predatory sequence as a framework, we identify problematic examples of antipredator defenses, separating them into protective mechanisms that are difficult to classify and those which act sequentially depending on context. We then discuss three ways of improving underlying terminological and definitional problems: (1) issues with English and polysemy, (2) overlapping aspects of similar mechanisms, and (3) unclear definitions. By scrutinizing the literature, we disentangle several opaque areas in the study of protective defense mechanisms and highlight questions that require further research. An unclear conceptual framework for protective defense mechanisms can lead to misconceptions in understanding the costs and benefits of defenses displayed by animals, while interchangeable terminologies and ambiguous definitions can hinder communication in antipredator studies. [ABSTRACT FROM AUTHOR]

Recognizing form and function of animal defenses is paramount to understanding the ecological and evolutionary forces behind predator and prey dynamics. Color patterns are strongly related to defensive strategies in animals. Some rely on camouflage to avoid detection, while others are brightly colored and conspicuously signal their noxiousness to potential predators. Still others combine cryptic dorsal coloration with colorful patches that are concealed in resting position but are facultatively unveiled by special behavior or simply during activity. Such hidden conspicuous color patches may be an intermediate stage in the evolution from camouflage to aposematism. Many species, especially treefrogs of the family Hylidae, are generally considered to be cryptic, yet show colorful patches on their flanks or thighs and have defensive skin secretions that may have unpalatable properties. We investigated whether the conspicuous black and yellow spotted pattern on the thighs of Eastern Gray Treefrogs (Hyla versicolor) serve as an aposematic signal. We conducted a palatability study to test whether Gray Treefrog skin secretions are unpalatable, and a clay model field study to test whether the conspicuous black and yellow thigh pattern is an aposematic warning coloration that reduces predation. Frog secretions were discriminated against during palatability assays, and clay models painted with a spotted black and yellow pattern suffered lower predation rates. Our findings support the hypothesis that hidden color patches act as aposematic signals in Gray Treefrogs and suggest that more species benefit from aposematic coloration than currently appreciated. [ABSTRACT FROM AUTHOR]

Crustaceans live on large colonial invertebrates for a variety of reasons, but in all cases must overcome the defenses of the host animal. We surveyed the crustaceans living on deep-sea octocorals collected during expeditions to the New England and Corner Rise seamounts (2003-2005) in the Northwest Atlantic and to the Aleutian Ridge (2004) in the North Pacific. Only a small number of crustacean species were found on octocorals in the Northwest Atlantic but a great many species, especially amphipods, were found on octocorals in the Northwest Pacific. We suggest that this disparity is due to both the differences in octocoral host dominance as well as differences in the available species pool between the two oceans. [ABSTRACT FROM AUTHOR]

This article discusses the molecular mechanisms of animal toxins, venoms, and antivenoms. Venoms have evolved in many animals as a means of defense or attack, and they contain various toxins that affect different systems in prey, victims, and predators. The article highlights the importance of studying the structure and mechanisms of action of animal toxins and venoms for the development of new drugs and effective treatments for venomous animal bites. It also mentions the discovery of new toxins and the addition of new venomous animal species, such as the platypus and slow lorises. The authors emphasize the need for further research in this field. [Extracted from the article]

Animal defences against infection involve two distinct but complementary mechanisms: tolerance and resistance. Tolerance measures the animal's ability to limit detrimental effects from a given infection, whereas resistance is the ability to limit the intensity of that infection. Tolerance is a valuable defence for highly prevalent, persistent or endemic infections where mitigation strategies based on traditional resistance mechanisms are less effective or evolutionarily stable. Selective breeding of amphibians for enhanced tolerance to Batrachochytrium spp. has been suggested as a strategy for mitigating the impacts of the fungal disease, chytridiomycosis. Here, we define infection tolerance and resistance in the context of chytridiomycosis, present evidence for variation in tolerance to chytridiomycosis, and explore epidemiological, ecological and evolutionary implications of tolerance to chytridiomycosis. We found that exposure risk and environmental moderation of infection burdens are major confounders of resistance and tolerance, chytridiomycosis is primarily characterized by variation in constitutive rather than adaptive resistance, tolerance is epidemiologically important in driving pathogen spread and maintenance, heterogeneity of tolerance leads to ecological trade-offs, and natural selection for resistance and tolerance is likely to be dilute. Improving our understanding of infection tolerance broadens our capacity for mitigating the ongoing impacts of emerging infectious diseases such as chytridiomycosis. This article is part of the theme issue 'Amphibian immunity: stress, disease and ecoimmunology'. [ABSTRACT FROM AUTHOR]

This study evaluated the physiological responses of subadult yellow-spotted Amazon river turtle, Podocnemis unifilis, to incremental crude protein levels (29%, 32%, 35%, and 39% CP) as extruded commercial feeds. The hematological and plasma biochemical parameters of P. unifilis were analyzed at 60, 120, and 180 days of the feeding trial. The increase in total thrombocyte, leukocyte, lymphocyte, heterophil, and eosinophil numbers, besides high respiratory burst activity showed an improvement in animal immune defense response to incremental protein in diets, acting together to maintain the integrity of the tissues against antigens and infectious agents. Elevated subadult P. unifilis plasma total cholesterol and triglyceride levels observed after increasing the feeding time (until 180 days) with incremented protein levels in artificial diets during captivity are a nutritional warning, related to the condition of being less physically active. Based on these results, periodic physiological evaluations are particularly important to ensure the healthy and adequate nutritional conditions of captive-bred animals, such as maintaining lower stocking densities of animals to avoid stress and, if possible, providing them with fresh food in addition to extruded artificial feed. [ABSTRACT FROM AUTHOR]

This article is structured in four approaches: historical, literary, anthropological and philosophical. From the historical perspective, it addresses the origins of the relationship between man and animals, in addition to considering the interactions that took place between the viringo and the Peruvian historical tradition. From the literary point of view, the naturalistic and symbolic representation of the canine in Peru is described, applied to narrative situations of shepherd dogs and urban stories as the case of parallels with militarized school life. From the anthropological point of view, it focuses mainly on the insertion of animals in culture, highlighting the religious and ritual aspect. From the moral or ethical philosophy, the mechanistic position of Descartes, the deontological ethics of Kant and the different theories of ecological ethics in defense of animals, such as the position of Bentham, Singer, Regan and Nussbaum, are approached. The logic of Cartesian dominion and the different naturalist positions in favor of animal law, who apply the concept of personhood to irrational beings, are criticized. Finally, a realistic animal ethics is proposed, which helps to avoid any kind of mistreatment, abuse and exploitation. [ABSTRACT FROM AUTHOR]

Intraspecific predation is a special case of prey–predator system that is taxonomically widespread. While a heterospecific predator's main goal is to achieve nutrition, intraspecific predation provides conspecifics with other benefits including elimination of competitors for resources and mates. Traditionally intraspecific predation is termed based on the context they occur within, for example egg cannibalism, infanticide and sexual cannibalism. These diverse forms of intraspecific predation and the strategies by which animals are known to deter them are summarized categorically in this review. The diversity of defence strategies animals deploy against conspecific predators is appreciable and raises interesting questions on their evolution for future research. [ABSTRACT FROM AUTHOR]

Reproduction is a central activity for all living organisms but is also associated with a diversity of costs that are detrimental for survival. Until recently, the cost of cancer as a selective force has been poorly considered. Considering 191 mammal species, we found cancer mortality was more likely to be detected in species having large, rather than low, litter sizes and long lactation lengths regardless of the placentation types. However, increasing litter size and gestation length are not per se associated with an enhanced cancer mortality risk. Contrary to basic theoretical expectations, the species with the highest cancer mortality were not those with the most invasive (i.e. haemochorial) placentation, but those with a moderately invasive (i.e. endotheliochorial) one. Overall, these results suggest that (i) high reproductive efforts favour oncogenic processes' dynamics, presumably because of trade-offs between allocation in reproduction effort and anti-cancer defences, (ii) cancer defence mechanisms in animals are most often adjusted to align reproductive lifespan, and (iii) malignant cells co-opt existing molecular and physiological pathways for placentation, but species with the most invasive placentation have also selected for potent barriers against lethal cancers. This work suggests that the logic of Peto's paradox seems to be applicable to other traits that promote tumorigenesis. [ABSTRACT FROM AUTHOR]

Cadmium is a heavy metal, dangerous environmental pollutant that negatively affects the body and the functioning of its organs and systems: blood, heart, liver, kidneys, and nervous system. It also harms the immune system, reducing the body's resistance to infections and increasing the risk of developing allergic, autoimmune, and oncological diseases. We studied the indicators of the humoral and nonspecific links of the immune system in young cattle subject to cadmium loading and the effects of a feed supplement and a liposomal preparation. The animals were divided into three groups of 5 each. Cadmium loading was attained by feeding cadmium chloride with feed in the dose of 0.04 mg/kg of the animal's body weight. The animals of the experimental groups were additionally given Metisevit and Butaselmevit. Usage of these drugs was accompanied by strengthening of the immune status of the body of young cattle, including increased bactericidal and lysozyme activities of blood serum, increased phagocytic activity, and phagocytic index, simultaneously with decrease in the level of circulating immune complexes in blood. In the conditions of experimental cadmium loading, we observed the best results in strengthening of the immune defense of the animals after combined use of the Metisevit feed additive and the Butaselmevit liposomal drug. These changes in the body of young cattle were associated with the complex effect of the components of the feed supplement and the liposomal preparation. The advantages of the liposomal form of Butaselmevit were more pronounced and longer-lasting effects. The Metisevit supplement and Butaselmevit liposomal drug were observed to be highly effective when used together during cadmium loading. [ABSTRACT FROM AUTHOR]

The oxidative state of intestinal tracts of healthy animals were investigated after short-term intake of half-fin anchovy hydrolysates (HAHp) and their thermal or Maillard reaction products (MRPs). After one month of continuous oral gavage of HAHp, HAHp-heated products (HAHp-H), the MRPs of HAHp with 3% of glucose (HAHp-3%G MRPs), and the MRPs of HAHp with 3% of fructose (HAHp-3%F MRPs) at a dose of 1.0 g/kg of body weight per day into healthy ICR male mice, the concentrations of serum low-density and high-density lipoprotein cholesterol did not significantly change compared to the control group (CK, gavage with saline). Similar results were found for the interleukin-6 concentrations of all groups. By comparison, HAHp-H, HAHp-3%G MRPs, and HAHp-3%F MRPs administration decreased serum tumor necrosis factor-α concentration as compared to the CK group (p < 0.05). No histological damage was observed in the jejunum, ileum, and colonic tissues of all groups. However, HAHp-H treatment induced higher upregulation of Kelch-like ECH-associated protein 1, transcription factors Nrf-2, associated protective phase-II enzymes of NAD(P)H: quinine oxidoreductase-1, and hemoxygenase-1 in colon tissue, as well as higher upregulation of endogenous antioxidant enzymes, including copper/zinc superoxide dismutase, manganese superoxide dismutase, catalase, and glutathione peroxidase 2 than other groups (p < 0.05). Additionally, increases in Nε-carboxymethyllysine expression in the colonic tissues of all groups were consistent with their increased oligopeptide transporter 1 expressions. Our results suggest that the thermal products of HAHp might have a broad application prospect in improving antioxidant defense in vivo in healthy animals. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a sudden kidney dysfunction caused by aberrant reactive oxygen species (ROS) metabolism that results in high clinical mortality. The rapid development of ROS scavengers provides new opportunities for AKI treatment. Herein, the use of hydrogen‐terminated germanene (H‐germanene) nanosheets is reported as an antioxidative defense nanoplatform against AKI in mice. The simulation results show that 2D H‐germanene can effectively scavenge ROS through free radical adsorption and subsequent redox reactions. In particular, the H‐germanene exhibits high accumulation in injured kidneys, thereby offering a favorable opportunity for treating renal diseases. In the glycerol‐induced murine AKI model, H‐germanene delivers robust antioxidative protection against ROS attack to maintain normal kidney function indicators without negative influence in vivo. This positive in vivo antioxidative defense in living animals demonstrates that the present H‐germanene nanoplatform is a powerful antioxidant against AKI and various anti‐inflammatory diseases. [ABSTRACT FROM AUTHOR]

Aposematic bright colors have a key role for animal defense and can be expressed through metabolic production or by acquiring pigments from diet. Aposematic coloration can be related to both local adaptations and availability of trophic resources. The European fire salamander (Salamandra salamandra) shows significant color variability and occurs across a broad range of habitats. Here we combined field observations with common rearing experiments to disentangle the role of environmental conditions and local adaptations in determining aposematic coloration of salamander populations. We assessed color variation and measured habitat features and food availability in adults from 25 populations. Furthermore, we reared newborn larvae from 10 populations under different food availability and analyzed color of metamorphs. To assess color pattern, we measured the percentage of yellow covering the body, and the Hue, Saturation and Value of yellow coloration. Adult showed strong variation of color pattern; variation was strongly related to the individual's size, to habitat productivity and to food availability. Under common garden conditions, differences between populations were not anymore evident, and coloration was only affected by resource availability during larval development. Our results suggest that environmental conditions and food availability are more important than local adaptations in determining differences in aposematic color pattern. [ABSTRACT FROM AUTHOR]

Lysozymes are hydrolytic enzymes characterized by their ability to cleave the β-(1,4)-glycosidic bonds in peptidoglycan, a major structural component of the bacterial cell wall. This hydrolysis action compromises the integrity of the cell wall, causing the lysis of bacteria. For more than 80 years, its role of antibacterial defense in animals has been renowned, and it is also used as a preservative in foods and pharmaceuticals. In order to improve the antimicrobial efficacy of lysozyme, extensive research has been intended for its modifications. This manuscript reviews the natural antibiotic compound lysozyme with reference to its catalytic and non-catalytic mode of antibacterial action, lysozyme types, susceptibility and resistance of bacteria, modification of lysozyme molecules, and its applications in the food industry. [ABSTRACT FROM AUTHOR]

Simple Summary: Every student comes across traditional conceptions of the legal person during law school. Professors usually explain that humans and corporations are legal persons, and that legal personhood is the most important category within the legal system as legal persons can enter into different legal relations, hold rights, and bear duties. Nonhuman animals are usually not mentioned in courses of this sort. This article examines four traditional concepts of the legal person and argues that nonhuman animals can be considered persons according to each concept. It notes that the law does not consider the concept of the human the same as the concept of the legal person, and that animals may benefit from an ecumenical defense, considering that legal practitioners such as judges commonly use these four traditional concepts of legal personhood, sometimes in the same ruling. Since Roman law, the category of the legal person has been the most relevant legal category, allowing humans and entities to act within the law and enter into legal relations. The legal system does not consider nonhuman animals as legal persons but as property or as sentient beings regulated by the rules of property. Throughout history, there have been different concepts of the legal person, and some are still relevant today. This article examines four traditional concepts of legal personhood, arguing that nonhuman animals can be considered persons according to each concept. The article reaches three main conclusions. First, the legal person is not the same as the human. Second, the debate between the equivalence and the subset views poses a dilemma between a revolution or the reform of animals' legal status. Third, an ecumenical defense of animal legal personhood may benefit animals as it supports animal persons according to any of the traditional concepts of legal personhood. [ABSTRACT FROM AUTHOR]

High concentration of ammonia-N will inhibit the immune defense of aquatic animals. The neuroendocrine-immune (NEI) regulatory mechanism under ammonia-N stress has been systematically studied, but the final response mechanism of ammonia-N affecting the immune system remains unclear. To investigate the relationship among immune factors of Litopenaeus vannamei (L. vannamei) exposed to 0, 2, 10 and 20 mg/L ammonia-N, the determination of complement components, C-type lectins, proPO system, signal transduction pathway and phagocytosis as well as exocytosis were performed. The results showed that the expressions of complement components including C1q , MBL , ficolin and alpha-2 macroglobulin (A2M) and the complement receptor integrin were decreased significantly in ammonia-N treatment groups at 6,12 and 24 h. C-type lectins and signal transduction factors changed significantly. The decrease of phagocytosis-related genes and phagocytic activity were similar to the changes of complement components, C-type lectins and the signal pathway. The mRNA abundance of exocytosis-related genes was significantly down-regulated under ammonia-N exposure. Correspondingly, significantly changes occurred in the expressions of PPAE and PPO3 , immune factors-related genes (Pen3 , crustin , stylicins , ALFs and LYC) and inflammatory factors (HSP90 , TNFα , IL-16) in haemocytes. Eventually, the serine proteinase activity, PO activity, antibacterial activity and bacteriolytic activity in plasma were decreased significantly. In addition, we speculated that under ammonia-N stress, phagocytosis and exocytosis were affected by complement components, and C-type lectins through intracellular signal transduction pathway. Complement components may involve in the regulation of proPO-activating system to response to ammonia-N stress. This study helped to further understanding the relationship among immune factors of crustacean in response to environmental stress, which implied that when it comes to the decrease of immunity affected by environmental stress, we should not only focus on the mechanism of upstream neuroendocrine response, but also pay attention to the role of immune factors. • The expression of complement components significantly reduced under ammonia-N stress. • Phagocytosis may be affected by complement and C-type lectins under ammonia-N stress. • Complement components may involve in regulation of proPO-activating system of shrimp. • The cellular and humoral immune response were reduced under ammonia-N stress. • The immune factors contribute to the decrease of immunity under environmental stress. [ABSTRACT FROM AUTHOR]

Aggression is an important component of an animal's defense when protecting offspring from predators. Ground nesting birds use a variety of defense strategies. However, their choice according to situation context is poorly known, especially in nonpasserines and in the subtropics and tropics. The ability to distinguish between differently dangerous predator species and the opportunity to share defense with conspecifics are potentially important but little‐studied aspects of nest defense strategy. We experimentally studied the nest defense of Red‐Wattled Lapwing in an individually marked population in a desert area near Dubai, UAE. We used three stuffed models representing 1) a predator dangerous both to adults and to nests (a cat), 2) a nest predator (a raven), and 3) a harmless reference model (a moorhen). We confirmed that the lapwings distinguished between predator species (being most aggressive toward the cat, and least aggressive toward the moorhen) and adjusted their defense strategy accordingly. In addition, conspecific visitors play a variety of roles in parents' defense strategy. They can strengthen the parental reaction, or they can assist in distracting a predator. The visitors included not only nesting neighbors but also nonbreeding floaters. Both parents participated in nest defense to a similar extent, regardless of incubation stage and ambient temperature. This study provides new insight into the complexity of the defensive patterns in ground‐nesting birds inhabiting a hot environment. Comparative experimental research on a range of environments, with various bird species and predator models, can help us to understand the drivers of these defensive behavioral patterns. [ABSTRACT FROM AUTHOR]

• Milk exosomes was used to co-delivery of isobavachalcone and polymyxin. • Isobavachalcone and polymyxin exhibit good synergistic antimicrobial effects. • Milk exosomes improve the solubility and efficacy of isobavachalcone. Milk is not only a source of nutrients, but also contains exosomes (Exo) that can serve as a vehicle for drug delivery. Here, we obtained bovine milk Exo using three efficient methods, demonstrating high quality for commercial production. The optimized Exo displayed a size of 105.2 nm and an entrapment efficiency of 88.4 %. The Exo has been functionalized with a combination therapy comprising isobavachalcone (IS) and polymyxin B (PB), referred to as IP-Exo. The antibacterial efficacy of IP-Exo was significantly enhanced, enabling the elimination of 99 % of multidrug-resistant (MDR) bacterial pathogens in 4 h. Furthermore, scanning electron microscopy images demonstrated that the drug combination led to the complete dismantling of the bacterial structure. IP-Exo showed nearly 100 % microbial inhibition in fresh orange juice and accelerated wound healing in mouse models. Collectively, IP-Exo provides excellent potential for application within the food industry and animal husbandry as a defense against bacterial pathogens. [ABSTRACT FROM AUTHOR]

Ferroptosis, a kind of programmed cell death, is characterized with iron-dependent lipid ROS buildup, which is considered as an important cellular immunity in resisting intracellular bacterial infection in mammalian macrophages. In this process, lipid ROS oxidizes the bacterial biofilm to inhibit intracellular bacteria. However, the function of ferroptosis in invertebrate remains unknown. In this study, the existence of ferroptosis in Apostichopus japonicus coelomocytes was confirmed, and its antibacterial mechanism was investigated. First, our results indicated that the expression of glutathione peroxidase (Aj GPX4) was significantly inhibited by 0.21-fold (p < 0.01) after injecting A. japonicus with the ferroptosis inducer RSL3, and the contents of MDA (3.93-fold, p < 0.01), ferrous iron (1.40-fold, p < 0.01), and lipid ROS (3.10-fold, p < 0.01) were all significantly increased under this condition and simultaneously accompanied with mitochondrial contraction and disappearance of cristae, indicating the existence of ferroptosis in the coelomocytes of A. japonicus. Subsequently, the contents of ferrous iron (1.40-fold, p < 0.05), MDA (2.10-fold, p < 0.01), ROS (1.70-fold, p < 0.01), and lipid ROS (2.50-fold, p < 0.01) were all significantly increased, whereas the mitochondrial membrane potential and GSH/GSSG were markedly decreased by 0.68-fold (p < 0.05) and 0.69-fold (p < 0.01) under Vibrio splendidus (AJ01) infection. This process could be reversed by the iron-chelating agent deferoxamine mesylate, which indicated that AJ01 could induce coelomocytic ferroptosis. Moreover, the results demonstrated that the intracellular AJ01 load was clearly decreased to 0.49-fold (p < 0.05) and 0.06-fold (p < 0.01) after treating coelomocytes with RSL3 and ferrous iron, which indicated that enhanced ferroptosis could inhibit bacterial growth. Finally, subcellular localization demonstrated that ferrous iron efflux protein ferroportin (Aj FPN) and intracellular AJ01 were co-localized in coelomocytes. After Aj FPN interference (0.58-fold, p < 0.01), the signals of ferrous iron and lipid ROS levels in intracellular AJ01 were significantly reduced by 0.38-fold (p < 0.01) and 0.48-fold (p < 0.01), indicating that Aj FPN was an important factor in the introduction of ferroptosis into intracellular bacteria. Overall, our findings indicated that ferroptosis could resist intracellular AJ01 infection via Aj FPN. These findings provide a novel defense mechanism for aquatic animals against intracellular bacterial infection. • Ferroptosis program was conservative in sea cucumber Apostichopus japonicus. • Ferroptosis might play an important role in AJ01 infection. • A. japonicus coelomocytes can introduce ferroptosis-induced oxidative pressure into intracellular AJ01 via Aj FPN to suppress intracellular AJ01 growth during infection. [ABSTRACT FROM AUTHOR]

Neutrophils are the most abundant circulating white blood cells and one of the major cell types of the innate immune system. Neutrophil extracellular traps (NETs) are a result of the extracellular release of nuclear chromatin from the ruptured nuclear envelope and plasma membrane. The externalized chromatin is an ancient defense weapon for animals to entrap and kill microorganisms in the extracellular milieu, thus protecting animals ranging from lower invertebrates to higher vertebrates. Although the externalized chromatin has the advantage of acting as anti‐infective to protect against infections, extracellular chromatin might be problematic in higher vertebrate animals as they have an adaptive immune system that can trigger further immune or autoimmune responses. NETs and their associated nuclear and/or cytoplasmic components may induce sterile inflammation, immune, and autoimmune responses, leading to various human diseases. Though important in human pathophysiology, the cellular and molecular mechanisms of NET formation (also called NETosis) are not well understood. Given that nuclear chromatin forms the backbone of NETs, the nucleus is the root of the nuclear DNA extracellular traps. Thus, nuclear chromatin decondensation, along with the rupture of nuclear envelope and plasma membrane, is required for nuclear chromatin extracellular release and NET formation. So far, most of the literature focuses on certain signaling pathways, which are involved in NET formation but without explanation of cellular events and morphological changes described above. Here, we have summarized emerging evidence and discuss new mechanistic understanding, with our perspectives, in NET formation in neutrophils. [ABSTRACT FROM AUTHOR]

Every ecosystem shows multiple levels of species interactions, which are often difficult to isolate and to classify regarding their specific nature. For most of the observed interactions, it comes down to either competition or consumption. The modes of consumption are various and defined by the nature of the consumed organism, e.g., carnivory, herbivory, as well as the extent of the consumption, e.g., grazing, parasitism. While the majority of consumers are animals, carnivorous plants can also pose a threat to arthropods. Water fleas of the family Daphniidae are keystone species in many lentic ecosystems. As most abundant filter feeders, they link the primary production to higher trophic levels. As a response to the high predatory pressures, water fleas have evolved various inducible defenses against animal predators. Here we show the first example, to our knowledge, in Ceriodaphnia dubia of such inducible defenses of an animal against a coexisting plant predator, i.e., the carnivorous bladderwort (Utricularia x neglecta Lehm, Lentibulariaceae). When the bladderwort is present, C. dubia shows changes in morphology, life history and behavior. While the morphological and behavioral adaptations improve C. dubia's survival rate in the presence of this predator, the life-history parameters likely reflect trade-offs for the defense. [ABSTRACT FROM AUTHOR]

Dietary selenium (Se) supplementation is a standard practice, using either an inorganic form, such as sodium selenite (SS) or organic forms, like SeYeasts (SY) or pure forms of selenomethionine (SeMet). Hydroxy-selenomethionine (OH-SeMet) is a chemically synthesized organic Se form and has been proven to be efficient in transferring Se from the diet to muscle compared with SS or SY products. The transfer of Se in tissues, in fact, leads to the buildup of a Se reserve as SeMet in the body that participates in maintaining effective antioxidant defenses and supports animal performance, particularly under challenging conditions. This trial aimed to determine the effects of different Se sources on the productive and reproductive performance of sows and on their progeny. Sows (n = 120) were allocated in individual cages in one of the three treatments according to the number of parities, number of piglets in previous parturition, body condition score and initial body weight. The experiment lasted 141 days (from the insemination of sows up to the weaning of the piglets at 21 days). A corn-soybean-based basal diet was formulated to meet the nutrient requirements of the sows during gestation and lactation. The Se supplementation was 0.35 ppm of Se either from SS, SY or OH-SeMet. The number of total piglets born showed a tendency (P = 0.06) for treatments fed organic Se sources (15.6 OH-SeMet; 15.4 SY vs 14 SS) with no differences on the litter weight at birth. However, sows fed OH-SeMet weaned more piglets (13.4) than the other treatments (12.5 SY and 12.2 SS, respectively, P < 0.01). The litter weight at weaning showed no differences among treatments (73.4, 70.4 and 75.9kg for SS, SY and OH-SeMet, respectively). The feed conversion of the sows during lactation was also affected by the Se source, in which OH-SeMet showed a significantly reduced FCR of 2.6 vs 3.0 and 3.1 for SS and SY, respectively (P < 0.01). Piglets fed organic sources showed a decreased diarrhea incidence (scores 2 and 3) compared with SS (P < 0.001), respectively, 5.68 vs 3.28 and 3.27%. The Se concentration of sows' colostrum and milk of sows were numerically improved from SS to SY, but only significantly greater on OH-SeMet treatment. The same pattern of Se concentration in the milk was observed in the serum of piglets 48 h after birth (142, 122 and 228 μg/kg for SS, SY and OH-SeMet, respectively) and at weaning (85, 85 and 117 μg/kg for SS, SY and OH-SeMet, respectively). Feeding pure forms of organic Se, such as OH-SeMet supports the productive and reproductive performance of sows and improve the Se status of the progeny. Organic Se also reduces the diarrhea of piglets, compared with SS. [ABSTRACT FROM AUTHOR]

Older humans and animals often exhibit reduced immune responses to infection and vaccination, and this often directly correlates to the numbers and frequency of naive T (Tn) cells. We found such a correlation between reduced numbers of blood CD8+ Tn cells and severe clinical outcomes of West Nile virus (WNV) in both humans naturally exposed to, and mice experimentally infected with, WNV. To examine possible causality, we sought to increase the number of CD8 Tn cells by treating C57BL/6 mice with IL‐7 complexes (IL‐7C, anti‐IL‐7 mAb bound to IL‐7), shown previously to efficiently increase peripheral T‐cell numbers by homeostatic proliferation. T cells underwent robust expansion following IL‐7C administration to old mice increasing the number of total T cells (>fourfold) and NS4b:H‐2Db‐restricted antigen‐specific CD8 T cells (twofold). This improved the numbers of NS4b‐specific CD8 T cells detected at the peak of the response against WNV, but not survival of WNV challenge. IL‐7C‐treated old animals also showed no improvement in WNV‐specific effector immunity (neutralizing antibody and in vivo T‐cell cytotoxicity). To test quantitative limits to which CD8 Tn cell restoration could improve protective immunity, we transferred graded doses of Ag‐specific precursors into old mice and showed that injection of 5400 (but not of 1800 or 600) adult naive WNV‐specific CD8 T cells significantly increased survival after WNV. These results set quantitative limits to the level of Tn reconstitution necessary to improve immune defense in older organisms and are discussed in light of targets of immune reconstitution. [ABSTRACT FROM AUTHOR]

Background and Aims Many angiosperms can secrete both floral (FN) and extrafloral (EFN) nectar. However, much remains unclear about how EFN and FN differ in secretion, composition and ecological function, especially when both FN and EFN are secreted on flowers of the same species. Methods Hemerocallis citrina flowers secrete both FN and EFN. The FN and EFN traits including volume, presentation pattern and temporal rhythms of secretion were compared by field observation. Sugar and amino acid contents were analysed using regular biochemical methods, whereas the proteome was investigated by combined gel-based and gel-free approaches. Animal feeders on FN and EFN were investigated by field observation. Hemerocallis citrina plants were exposed by soil drenching to two systemic insecticides, acetamiprid and imidacloprid, and the concentration of these in FN and EFN was measured by ultra-high performance liquid chromatography coupled with mass spectrometry. Key Results Hemerocallis citrina FN was concentrated and sucrose dominant, secreted in the mature flower tube and served as a reward for pollinators. Conversely, EFN was hexose rich, more dilute and less rich in sugar and amino acids. EFN was secreted on the outside of developing floral buds, and was likely to attract predatory animals for defence. EFN had fewer phenolics, but more pathogenesis-related components, such as chitinase and glucanase. A significantly different proteomic profile and enzymatic activities between FN and EFN suggest that they had different biosynthesis mechanisms. Both neonicotinoid insecticides examined became present in both nectar types soon after application, but in greater concentration within EFN; EFN also attracted a wider range of insect species than FN. Conclusions Hemerocallis citrina FN and EFN differed in production, composition and ecological function. The EFN pathway could be a significant way for neonicotinoids to enter the wild food chain, and must be considered when evaluating the risks to the environment of other systemic insecticides. [ABSTRACT FROM AUTHOR]

Defensive chemicals are used by plants and animals to reduce the risk of predation through different mechanisms, including toxins that cause injury and harm (weapons) and unpalatable or odiferous compounds that prevent attacks (deterrents). However, whether effective defences are both toxins and deterrents, or work in just one modality is often unclear.In this study, our primary aim was to determine whether defensive compounds stored by nudibranch molluscs acted as weapons (in terms of being toxic), deterrents (in terms of being distasteful) or both. Our secondary aim was to investigate the response of different taxa to these defensive compounds.To do this, we identified secondary metabolites in 30 species of nudibranch molluscs and investigated their deterrent properties using antifeedant assays with three taxa: rock pool shrimp, Palaemon serenus, and two fish species: triggerfish Rhinecanthus aculeatus and toadfish Tetractenos hamiltoni. We compared these results to toxicity assays using brine shrimp Artemia sp. and previously published toxicity data with a damselfish Chromis viridis.Overall, we found no clear relationship between palatability and toxicity, but instead classified defensive compounds into the following categories: Class I & II—highly unpalatable and highly toxic; Class I—weakly unpalatable and highly toxic; Class II—highly unpalatable but weakly toxic; WR (weak response)—weakly unpalatable and weakly toxic. We also found eight extracts from six species that did not display activity in any assays indicating they may have very limited chemical defensive mechanisms (NR, no response). We found that the different classes of secondary metabolites were similarly unpalatable to fish and shrimp, except extracts from Phyllidiidae nudibranchs (isonitriles) that were highly unpalatable to shrimp but weakly unpalatable to fish.Our results pave the way towards better understanding how animal chemical defences work against a variety of predators. We highlight the need to disentangle weapons and deterrents in future work on anti‐predator defences to better understand the foraging decisions faced by predators, the resultant selection pressures imposed on prey and the evolution of different anti‐predator strategies. [ABSTRACT FROM AUTHOR]

Cyclic oligonucleotide-based antiphage signaling system (CBASS) immunity is a widespread form of antiphage defense in bacteria and archaea. Each CBASS operon encodes a cGAS/DncV-like Nucleotidyltransferase (CD-NTase) enzyme that synthesizes a nucleotide second messenger in response to viral infection. An associated Cap effector protein then binds the nucleotide signal and executes cell death to destroy the host cell and block phage propagation. Here we build upon recent advances to establish rules controlling each step of CBASS activation and antiphage defense. Comparative analysis of CBASS, CRISPR, Pycsar, and cGAS-STING immunity provides insight into the evolution of phage defense and animal innate immunity and highlights new questions emerging in the role of nucleotide second messenger signaling in host–virus interactions. [ABSTRACT FROM AUTHOR]

Phagocytosis, an innate defense mechanism of multicellular animals, is initiated by specialized surface receptors. A phagocytic receptor expressed by human polymorphonuclear granulocytes, the major professional phagocytes in our body, is one of the fastest evolving human proteins implying a special role in human biology. This receptor, CEACAM3, is a member of the CarcinoEmbryonic Antigen-related Cell Adhesion Molecule (CEACAM) family and dedicated to the immediate recognition and rapid internalization of human-restricted pathogens. In this focused contribution, we will review the special adaptations of this protein, which co-evolves with different species of mucosa-colonizing bacteria. While the extracellular Immunoglobulin-variable (Ig V)-like domain recognizes various bacterial adhesins, an Immunoreceptor Tyrosine-based Activation Motif (ITAM)-like sequence in the cytoplasmic tail of CEACAM3 constitutes the central signaling hub to trigger actin rearrangements needed for efficient phagocytosis. A major emphasis of this review will be placed on recent findings, which have revealed the multi-level control of this powerful phagocytic device. As tyrosine phosphorylation and small GTPase activity are central for CEACAM3-mediated phagocytosis, the counterregulation of CEACAM3 activity involves the receptor-type protein tyrosine phosphatase J (PTPRJ) as well as the Rac-GTP scavenging protein Cyri-B. Interference with such negative regulatory circuits has revealed that CEACAM3-mediated phagocytosis can be strongly enhanced. In principle, the knowledge gained by studying CEACAM3 can be applied to other phagocytic systems and opens the door to treatments, which boost the phagocytic capacity of professional phagocytes. • CEACAM3 is a phagocytic receptor found on granulocytes of higher primates. • CEACAM3 triggers massive, actin-driven lamellipodia formation upon engagement. • Dephosphorylation by RPTPJ and Rac-GTP scavenging by Cyri-B limit CEACAM3 action. • Interference with RPTPJ or Cyri-B can boost CEACAM3-mediated phagocytosis of human pathogens. [ABSTRACT FROM AUTHOR]

Coumarins are bioactive molecules that often serve as defenses in plant and animal systems, and understanding their fundamental behavior is essential for understanding their bioactivity. Aesculetin (6,7-dihydroxycoumarin) has recently attracted attention due to its ability to act as an antioxidant, but little is known about its photophysical properties. The fluorescence lifetimes of its neutral and anion form in water are 19 ± 2 ps and 2.3 ± 0.1 ns, respectively. Assuming the short lifetime of the neutral is determined by ESPT, we estimate kPT ~ 5 × 1010 s–1. Using steady-state and time-resolved fluorescence spectroscopy, we determine its ground and excited-state p K a 1 to be 7.3 and –1, respectively, making it one of the strongest photoacids of the natural coumarins. Aesculetin exhibits a strong pH dependence of the relative fluorescence quantum yield becoming much more fluorescent above p K a 1 . The aesculetin anion has slightly photobasic character. We also report that aesculetin forms a fluorescent catechol-like complex with boric acid, and this complex has a p K c of 5.6. [ABSTRACT FROM AUTHOR]

This paper presents the results of the study of low temperature effects of moderate stress intensity and the mineral premix "PMVS" on some indicators of calf defense abilities in postnatal ontogenesis to determine the parameters that can be used as a way of increasing the resistance and the defense abilities of animals to adverse environmental influences. The values obtained from the studied parameters show the change in the resistance of calves in the postnatal period. Thus, the increase of the biological value of the ration, by including the mineral premix "PMVS" and the application of the low temperature of a moderate stress intensity have led to an increased serum phagocytic activity, bactericidal activity and lysozyme activity throughout the experimental period. During the whole research period, the diurnal weight gain in the experimental group was 766 g. Maintenance of the organism's homeostasis within optimal physiological limits is the main task of the animals physiology. Determination of the parameters of influence of the food and heat factors on homeostasis and calf development in postnatal ontogenesis allows to create favorable conditions that can facilitate the acceleration of the functional maturation of vital organs and systems, increase the organism's resistance and adaptive abilities of the organism to the influence of stress factors and the realization of the genetic potential of animals. [ABSTRACT FROM AUTHOR]

The article discusses how librarians can increase children's reading comprehension, motivation and pleasure with knowledge. Topics covered include the key elements of reading, namely, decoding and understanding what the words on a page mean, how to build and increase children's background knowledge and how the library and librarians can spark curiosity in children in order to build knowledge.

Animals living in groups with high conspecific densities typically decrease their level of plastic anti‐predatory defence because its benefits diminish with reduced per capita predation risk (a benefit of aggregation), whereas its costs increase due to intensifying competition and increased infection risk. Furthermore, phenotypic responses that provide protection from predators are also often disadvantageous against competitors and infections.Such a trade‐off may be absent when the same phenotype provides an effective defence against both predators and competitors, as is the case with some chemical defences. For such multifunctional defensive traits, both predation risk and high conspecific density are expected to increase defence expression while exposure to both predators and conspecifics may result in non‐additive effects whereby the defence level induced by two enemies is lower than the sum of responses induced by either of them alone.We tested this theoretical prediction by studying the effects of multiple enemies on chemical defence in a vertebrate animal. We investigated patterns of change in toxin production of common toad Bufo bufo tadpoles following exposure to different conspecific densities and the simultaneous presence or absence of chemical cues on predation risk.We found that tadpoles significantly increased their production of bufadienolide toxins in response to high tadpole density, as well as to predation risk when tadpole density was low. Although the response in bufadienolide production to predation risk was not significant at high tadpole density, the magnitude of anti‐predatory response did not differ significantly between low and high tadpole densities.These results show that toad tadpoles adjust their chemical defence to conspecific density and to predation risk simultaneously, and these two effects are more likely additive than non‐additive, at least within the range of densities and predation‐risk levels studied here. Nevertheless, the trend we found suggests that toxin levels induced by very high conspecific density might weaken the chemical response to predators, which is relevant for the evolutionary ecology of chemical defences, as well as for the conservation of fauna impacted by toxic invaders. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

This study was carried out with the aim of expanding passive surveillance to the Institute of Agricultural Defense of Rio Grande do Norte through Education in Animal Health Defense of students of the 1st year of the Technical Course in Agriculture of the Federal Institute of Rio Grande do Norte - Campus Apodi, between the months of October and December 2019, totaling 104 students. Initially, a structured questionnaire was applied in order to measure the level of knowledge on the subject. In a second moment, lectures and training courses were carried out on the main Animal Health Programs carried out by the state defense agency. Finally, the same questionnaire was applied for evaluation purposes. Regarding the knowledge about the Institute of Agricultural Defense and Inspection of Rio Grande do Norte, it was observed that only 9.6% of the students had knowledge about the agency, but 54.8% knew of its role. On the other hand, it was noticed that after the lecture, 93.9% said they knew about the organ, and 88.8% knew about its performance. Only 16.3% of the students were aware of the information about the National Herbivore Rabies Control Program at the first meeting, and only 42.3% mastered the main form of rabies transmission in herbivores. After lectures, 86.7% of learning on the subject was obtained, with 88.8% of knowledge about the ways in which the disease is transmitted. Therefore, an efficient, comprehensive and continuous animal health education program on Animal Health Defense is necessary. [ABSTRACT FROM AUTHOR]

Humoral and cellular immune responses provide animals with major defences against harmful pathogens. While it is often assumed that immune genes undergo rapid diversifying selection, this assumption has not been tested in many species. Moreover, it is likely that different classes of immune genes experience different levels of evolutionary constraint, resulting in varying selection patterns. We examined the evolutionary patterns for a set of 91 canonical immune genes of North American monarch butterflies (Danaus plexippus), using as an outgroup the closely related soldier butterfly (Danaus eresimus). As a comparison to these immune genes, we selected a set of control genes that were paired with each immune for approximate size and genomic location. As a whole, these immune genes had a significant but modest reduction in Tajima's D relative to paired‐control genes, but otherwise did not show distinct patterns of population genetic variation or evolutionary rates. When further partitioning these immune genes into four functional classes (recognition, signalling, modulation, and effector), we found distinct differences among these groups. Relative to control genes, recognition genes exhibit increased nonsynonymous diversity and divergence, suggesting reduced constraints on evolution, and supporting the notion that coevolution with pathogens results in diversifying selection. In contrast, signalling genes showed an opposite pattern of reduced diversity and divergence, suggesting evolutionary constraints and conservation. Modulator and effector genes showed no statistical differences from controls. These results are consistent with patterns found in immune genes in fruit flies and Pieris butterflies, suggesting that consistent selective pressures on different classes of immune genes broadly govern the evolution of innate immunity among insects. [ABSTRACT FROM AUTHOR]

After calving, lipid mobilization caused by increased nutrient demands for lactation leads to elevated circulating concentrations of nonesterified fatty acids (NEFA). Excessive NEFA levels have previously been identified as a major risk factor for postpartum immunosuppression. The aim of this study was to investigate changes in global transcriptomic gene expression of peripheral blood mononuclear cells (PBMC) in dairy cows offered different early lactation diets (high concentrate, n = 7; medium, n = 8; or low, n = 9) and with differing circulating levels of NEFA. Cows were classified as having NEFA concentrations of either <500 µ M (low, n = 6), 500 to 750 µ M (medium, n = 8) or >750 µ M (high, n = 10) at 14 d in milk. Plasma urea concentrations were greater for cows on the high concentrate diet but β-hydroxybutyrate and glucose concentrations did not differ significantly between either dietary treatments or NEFA groups. Cows with high NEFA weighed more at drying off and suffered greater body condition score loss after calving. The PBMC were isolated at 14 d in milk, and RNA was extracted for RNA sequencing. Differential gene expression was analyzed with DESeq2 with q-value for false discovery rate control followed by Gene Ontology Enrichment. Although there were no differentially expressed genes associated with lactation diet, 304 differentially expressed genes were identified between cows with high and low circulating NEFA, with 118 upregulated and 186 downregulated. Gene Ontology enrichment analysis demonstrated that biological adhesion and immune system process were foremost among various PBMC functions which were altered relating to body defenses and immunity. High NEFA concentrations were associated with inhibited cellular adhesion function by downregulating 20 out of 26 genes (by up to 17-fold) related to this process. Medium NEFA concentrations altered a similar set of functions as high NEFA, but with smaller enrichment scores. Localization and immune system process were most significant, with biological adhesion ranking only eleventh. Our results demonstrated that increased circulating NEFA concentrations, but not diet, were associated with immune system processes in PBMC in early lactation cows. Leukocyte cell-to-cell adhesion was inhibited when the NEFA concentration exceeded 750 µ M , which would reduce the efficiency of diapedesis and so contribute to decreased body defense mechanisms and predispose animals to infection. [ABSTRACT FROM AUTHOR]

Mucus layer that covers the body surface of various animal functions as a defense barrier against microbes, environmental xenobiotics, and predators. Previous studies have reported that L-amino acid oxidase (LAAO), present in several animal fluids, has potent properties against pathogenic bacteria, viruses, and parasites. LAAO catalyzes the oxidative deamination of specific L-amino acids with the generation of hydrogen peroxide and L-amino acid metabolites. Further, the generated hydrogen peroxide is involved in oxidation (direct effect) while the metabolites activate immune responses (indirect effect). Therefore, LAAO exhibits two different mechanisms of bioactivation. Previously, we described the selective, specific, and local oxidative and potent antibacterial actions of various LAAOs as potential therapeutic strategies. In this review, we focus on their biochemical features, enzymatic regulations, and biomedical applications with a view of describing their probable role as biochemical agents and biomarkers for microbial infections, cancer, and autoimmune-mediated diseases. We consider that LAAOs hold implications in biomedicine owing to their antimicrobial activity wherein they can be used in treatment of infectious diseases and as diagnostic biomarkers in the above-mentioned diseased conditions. Key points: •Focus on biochemical features, enzymatic regulation, and biomedical applications of LAAOs. •Mechanisms of antimicrobial activity, inflammatory regulation, and immune responses of LAAOs. •Potential biomedical application as an antimicrobial and anti-infection agent, and disease biomarker. [ABSTRACT FROM AUTHOR]

Chemical defences in animals are both incredibly widespread and highly diverse. Yet despite the important role they play in mediating interactions between predators and prey, extensive differences in the amounts and types of chemical compounds can exist between individuals, even within species and populations. Here we investigate the potential role of environment and development on the chemical defences of warningly coloured butterfly species from the tribe Heliconiini, which can both synthesize and sequester cyanogenic glycosides (CGs). We reared 5 Heliconiini species in captivity, each on a single species-specific host plant as larvae, and compared them to individuals collected in the wild to ascertain whether the variation in CG content observed in the field might be the result of differences in host plant availability. Three of these species were reared as larvae on the same host plant, Passiflora riparia, to further test how species, sex, and age affected the type and amount of different defensive CGs, and how they affected the ratio of synthesized to sequestered compounds. Then, focusing on the generalist species Heliconius numata, we specifically explored variation in chemical profiles as a result of the host plant consumed by caterpillars and their brood line, using rearing experiments carried out on two naturally co-occurring host plants with differing CG profiles. Our results show significant differences in both the amount of synthesized and sequestered compounds between butterflies reared in captivity and those collected in the field. We also found a significant effect of species and an effect of sex in some, but not all, species. We show that chemical defences in H. numata continue to increase throughout their life, likely because of continued biosynthesis, and we suggest that variation in the amount of synthesized CGs in this species does not appear to stem from larval host plants, although this warrants further study. Interestingly, we detected a significant effect of brood lines, consistent with heritability influencing CG concentrations in H. numata. Altogether, our results point to multiple factors resulting in chemical defence variation in Heliconiini butterflies and highlight the overlooked effect of synthesis capabilities, which may be genetically determined to some extent. [ABSTRACT FROM AUTHOR]

The aim of this paper is to assess the central role the imagination acquires in Pierre Gassendi's logic. I trace the structuring scheme of the three acts of the mind—common to a good number of late scholastic and early modern logics—to the Thomistic notion of the movement of reasoning in knowledge and argue that Gassendi revisits this notion in his logic. The three acts scheme is from the beginning a bridge between logic and the natural philosophical treatment of the soul. I show how Gassendi's take on the three acts is similarly poised between his Logic and his Physics and I discuss the rationale, sources and consequences of his attribution of the three acts to the imagination. I argue for the following points: Gassendi's conception of the logical role of the imagination answers to his empiricist epistemology, his naturalized view of the mind (which involves a defense of thinking in animals) and his notion of a natural logic; it is also operative in his pairing of the formal mechanism of logical operations with a progressive mechanism of the operations of the mind; and it serves as a counterpart to his experimental understanding of the progress of knowledge. [ABSTRACT FROM AUTHOR]

Abamectin, a pesticide of 16-member macrocyclic lactones, is widely applied in agriculture. As an important environmental factor, pesticides pose a great threat to defense system in aquatic animals. Procambarus clarkii is one of the most important economic aquatic animals in China. It is necessary to explore the defense mechanism of P. clarkii to abamectin. In this study, P. clarkii were exposed to 0, 0.2, 0.4, 0.6 mg/L abamectin, immune- and antioxidant-related enzymes activities, genes expression levels, and histological observations were used to analyze the defense capacity of P. clarkii to abamectin. With increasing abamectin concentration, reactive oxygen species (ROS) level and malondiadehyde (MDA) content increased significantly. Meanwhiile, acid phosphate (ACP), alkaline phosphatase (AKP) activities, total haemocyte counts (THC), and Crustin expression level decreased significantly, superoxide dismutase (SOD), catalase (CAT) activities, total antioxidant capacity (T-AOC), and GPX expression level also decreased significantly. Hematoxylin & eosin (H&E) observation showed that with increasing abamectin concentration, hepatopancreas were damaged, especially membrane structure. Through TUNEL observation and apoptosis-related genes (PcCTSL , Bcl-2 , Bax , BI-1 , PcCytc , caspase-3) expression levels, with increasing abamectin concentration, apoptosis rate increased significantly. Results of this study indicated that abamectin caused oxidative damage to P. clarkii , resulting in damage to defense system, suppression of nonspecific immunity and antioxidation, and promotion of apoptosis. It provided theoretical basis for healthy P. clarkii culture, and for further study on defense mechanism of aquatic animals to pesticides. • Abamectin induced oxidative damage in P. clarkii. • Abamectin inhibited nonspecific immunity and antioxidant capacity. • Abamectin promoted apoptosis. [ABSTRACT FROM AUTHOR]

Animal defense system constitutes a series of distinct mechanisms that specifically defend against microbial invasion. Understanding these complex biological mechanisms is of paramount importance for implementing disease prevention strategies. In this study, the transcription factor, Akirin-2 was identified from ornamental fish Amphiprion clarkii and its involvement in immune response was characterized. A. clarkii Akirin-2 (AcAkirin-2) was identified as a highly conserved protein with two nuclear localization signals. In-vitro localization analysis in fathead minnow cells revealed that AcAkirin-2 is strictly localized to the nucleus. With regard to tissue-specific expression without immune challenge, AcAkirin-2 expression was highest in the brain and lowest in the liver. Immune challenge experiments revealed that AcAkirin-2 expression was the strongest in response to poly I:C. Overexpression of AcAkirin-2 alone did not enhanced NF-ĸB activity significantly in HEK293T cells; however, it significantly enhanced NF-ĸB activity in the presence of poly I:C. AcAkirin-2-mediated expression of antiviral genes was analyzed using qPCR in mullet kidney cells and plaque assay was performed to decipher the involvement of AcAkirin-2 in antiviral immunity. AcAkirin-2 overexpression significantly enhanced the expression of Viperin but not of Mx. Plaque assays revealed the ability of AcAkirin-2 to enervate VHSV titers. Taken together, this study unveiled the involvement of AcAkirin-2 in NF-ĸB-mediated transcription of antiviral genes. • Amphiprion clarkii Akirin-2 was identified and characterized. • Strong expression was observed with poly I:C. • AcAkirin-2 activates NF-ĸB transcription factors with the presence of poly I:C. • Over expression of AcAkirin-2 reduced VHSV titter. [ABSTRACT FROM AUTHOR]

• Apoptosis due to MPP+ reach a maximum after 120 h. • Pretreatment with copper sulfate inhibits apoptosis induced by MPP+. • Pretreatment with copper sulfate inhibits apoptosis both in striatum and midbrain. 1-Methyl-4-phenylpyridinium ion (MPP+)-induced neurotoxicity produces cellular damage resembling that encountered in Parkinson's disease. The mechanisms of cellular death after MPP+ include the participation of oxidative stress in the loss of dopaminergic neurons. Among the mechanisms of defense against oxidative stress, several copper-dependent proteins have been implicated: Cu/Zn-SOD, ceruloplasmin, and metallothionein. Another important mechanism of damage, is MPP + interference with mitochondrial respiration. Both, oxidative stress and inhibition of mitochondrial respiration may trigger apoptosis in the neurons after MPP+. The aim of the present study was to characterize the time-course of apoptosis induced by MPP+ to determine if copper sulfate pretreatment is able to prevent the activation of caspases and decreased the neuronal apoptosis. MPP+ was microinjected into rat striatum using a stereotactic frame. The results showed increased activities of caspases 8, 9 and 3, between 72–120 hours after administration of MPP+, both in striatum and midbrain. After this study, we tested the effect of CuSO 4 on MPP+ neurotoxicity, showing a diminution of the apoptotic damage induced by MPP+, decreased levels of enzymatic activity of caspases: 8 (-34 and -25 %), 9 (-25 and -42 %) and 3 (-40 and -29 %) in striatum and midbrain, respectively. Finally, we performed an immunohistochemical analysis, evidencing a decreased number of apoptotic cells in the groups pretreated with copper sulfate pretreatment compared to the control group. With these findings, it is concluded that pretreatment with copper sulfate may be a good alternative to prevent MPP+-induced apoptosis. [ABSTRACT FROM AUTHOR]

Camouflage is the most common form of antipredator defense, and is a textbook example of natural selection. How animals' appearances prevent detection or recognition is well studied, but the role of prey behavior has received much less attention. Here we report a series of experiments with twig-mimicking larvae of the American peppered moth Biston betularia that test the long-held view that prey have evolved postures that enhance their camouflage, and establish how food availability and ambient temperature affect these postures. We found that predators took longer to attack larvae that were resting in a twig-like posture than larvae resting flat against a branch. Larvae that were chilled or food restricted (manipulations intended to energetically stress larvae) adopted a less twig-like posture than larvae that were fed ad libitum. Our findings provide clear evidence that animals gain antipredator benefits from postural camouflage, and suggest that benefits may come at an energetic cost that animals are unwilling or unable to pay under some conditions. [ABSTRACT FROM AUTHOR]