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The size ofAstyanax mexicanusblind cavefish populations of North-East Mexico is a demographic parameter of great importance for investigating a variety of ecological, evolutionary and conservation issues. However, very few estimates have been obtained. For these mobile animals living in an environment difficult to explore as a whole, methods based on capture-mark-recapture are appropriate, but the feasibility of such approach and the interpretation of the results depend on several assumptions that must be carefully examined. Here, we provide evidence that minimally invasive genetic identification from captures at different time intervals can give insights on cavefish population size dynamics as well as other important demographic parameters of interest. We also provide tools to calibrate sampling and genotyping efforts necessary to reach a given level of precision. Our results suggest that the El Pachón cave population is currently very small, of an order of magnitude of a few hundreds of individuals, and is distributed in a relatively isolated area. The probable decline in population size in the El Pachón cave since the last census in 1971 raises serious conservation issues.

Changes in gene expression regulation during development are considered the main drivers of morphological evolution and diversification. Here, we analysed the embryonic transcriptomes of surface-dwelling and blind cave-adapted morphs of the species Astyanax mexicanus and their reciprocal F1 hybrids at tailbud stage. Comparing gene expression in parents and allelic expression ratios in hybrids, we found that ∼20% of the transcriptome is differentially expressed and that cis-regulatory changes are the main contributors to variations in early developmental gene expression in the two morphs. We provide a list of 108 cis-regulated genes that could contribute to cavefish developmental evolution, and further explore the regulatory mechanisms controlling the cellular and regional expression of rx3, a “master eye gene”. Using quantitative embryology approaches after fluorescent in situ hybridisation, cell transplantations and interference with signalling pathways, we show that rx3 cellular levels -controlling optic cell fates-are regulated in cis and in a cell-autonomous manner, whereas the size of rx3 domain -controlling eye size-depends on non-autonomous Wnt signalling. Altogether, we reveal how distinct mechanisms and regulatory modules can regulate developmental gene expression and shape developmental evolution, with negligible contribution of coding mutations.

Mice are macrosmatic animals that use olfaction as their main source of information to increase fitness; they process predator cues to assess risk, and plants and fruit cues to find nutritional resources and assess their quality or toxicity. In this study, we examined the effects of ethanol as an olfactory stimulus related to fruit rotting, against 2,4,5-trimethylthiazoline (TMT, a fox faeces compound), its native origin, the fox faeces and a negative control on avoidance, locomotor activity, and stress related behaviour, measured by the production of faecal boli. Our results showed that mice clearly avoided ethanol (P= The clear avoidance and behavioural effects of ethanol in mice have direct implications in laboratory animal research, where it is used widely. This avoidance effect could elicit stressful situations and modify behavioural and physiological responses in mice housed in research facilities. In addition, this avoidance could be used as a non-lethal, inexpensive and non-toxic tool in rodent pest management. To explain these results, we suggest ethanol as a probable cue for fruit ripening, in the wild, this chemical cue could convey primordial information about the ripening state of fruits, allowing animals to avoid over-ripe, unhealthy fruits.

Following the arrival of MATISSE, the second-generation of VLTI instrumentation is now complete and was simultaneously enhanced by a major facility upgrade including the NAOMI Adaptive Optics on the Auxiliary Telescopes. On the Unit Telescopes, significant efforts were also made to improve the injection stability into VLTI instruments. On top of GRAVITY's own evolution, its fringe tracker is now being used to allow coherent integrations on MATISSE (the so-called GRA4MAT project). Meanwhile, operations also evolved to be more flexible and make the most of an extended observing parameter space. In this context, we present an overview of the current VLTI performances. Finally, we will report on on-going improvements such as the extension of the longest baselines.

Animals in many phyla are adapted to and thrive in the constant darkness of subterranean environments. To do so, cave animals have presumably evolved mechano- and chemosensory compensations to the loss of vision, as is the case for the blind characiform cavefish, Astyanax mexicanus. Here, we systematically assessed the olfactory capacities of cavefish and surface fish of this species in the lab as well as in the wild, in five different caves in northeastern Mexico, using an olfactory setup specially developed to test and record olfactory responses during fieldwork. Overall cavefish showed lower (i.e., better) olfactory detection thresholds than surface fish. However, wild adult cavefish from the Pach&oacute, n, Sabinos, Tinaja, Chica and Subterr&aacute, neo caves showed highly variable responses to the three different odorant molecules they were exposed to. Pach&oacute, n and Subterr&aacute, neo cavefish showed the highest olfactory capacities, and Chica cavefish showed no response to the odors presented. We discuss these data with regard to the environmental conditions in which these different cavefish populations live. Our experiments in natural settings document the diversity of cave environments inhabited by a single species of cavefish, A. mexicanus, and highlight the complexity of the plastic and genetic mechanisms that underlie cave adaptation.

Stress is an important cause of illness and mortality in chick production. Stressors such as manipulation, absence of maternal care, transport, and housing can lead to welfare issues, immunodepression, and decreased productivity. The mother hen uropygial secretion analogue (MHUSA), a synthetic analog of a maternal semiochemical secretion, has been proven to protect chicks and broilers against stress, significantly reducing the heterophil-to-lymphocyte ratio. The aim of the present study was to test the effects of the MHUSA on chicks' stress when single-sprayed on their fluff at the age of 1 d. Two-hundred eighty ROSS 308 chicks were included in the study. At day 1, each chick received a spray of 200 μL of a 2% MHUSA aqueous solution (140 chicks) or the same amount of the excipient (control group, 140 chicks), and then chicks were housed in 2 separate rooms. To assess the persistence of the MHUSA after this single application, fluff was sampled from 10 chicks every day for 7 d and at day 13 and 19, weighed, placed in dichloromethane, and analyzed by gas chromatography. Blood smears and the bursa of Fabricius were collected every 3 d from 10 chicks of each group for 36 d to assess the heterophil-to-lymphocyte ratio and the bursa weight-to-BW ratio, respectively. Gas chromatography analysis showed that the MHUSA was present on chick fluff until day 5. The statistical analysis revealed that the heterophil-to-lymphocyte ratio was lower in the MHUSA group at day 4, 7, and 9 (P < 0.0001 for day 4 and 7; P = 0.0377 for day 9). The bursa weight-to-BW ratio was significantly higher in the MHUSA group than in the control group from day 4 until day 29. These results confirm the beneficial effects of the MHUSA on chicks' adaptation to the new environment and on bursa of Fabricius development, suggesting its potential role in improving chicks' immune response.

A better understanding of animal emotions is an important goal in disciplines ranging from neuroscience to animal welfare science, but few reliable tools exist for measuring these emotions. Play behaviour is generally recognized as a trigger of positive emotions in mammals, and previous studies have suggested that tail movement (a behaviour often seen during play) may indicate positive emotions in pigs, while ear movements may indicate negative emotions, or a decrease in positive emotions. This study investigated whether the provision of toys to solicit play behaviour in pigs was associated with tail and ear movement changes, with the goal of confirming the use of these movements as indicators of different emotions in pigs. Sixteen mini-pigs were divided into two identical rooms of 8 individuals. During 4 consecutive days, each animal participated in the study for a total of two days in two different situations: one Control session and one Play session. Each animal served as its own control. During Play sessions, pigs were placed in their own pens of two individuals, where two medium-sized dog toys were introduced. During Control sessions, animals were placed in their own pens, but no toy was provided. Behaviours were scored from video using continuous recording with an ethogram, which also allows to confirm that pigs play during Play sessions. Results showed a significant difference in tail movement duration between sessions (DF = 15; t = −3.40; p

Positive welfare is more than the absence of negative experiences. Nevertheless, there are few feasible animal-based measures for positive welfare. This study aimed to investigate whether object and social play behaviours in pigs, which is believed to trigger positive emotions, is linked to peripheral oxytocin and/or serotonin changes over time. Moreover, the study examines the relationship between tail movement, play behaviour, and peripheral levels of oxytocin and serotonin in animals that have the possibility to play, along with the approach towards humans and the difficulty/ease of working with the animals. At six months old, 10 mini-pigs from the Play group participated in one or two play sessions per day for three weeks. Eight mini-pigs from a Control group did not participate in play sessions. For each first play session, blood was sampled before the play session (T0) and 5–10 min after the play session ended (T1). The same procedure was performed each day for three weeks. For the Control group, blood samples were drawn at the same times as the experimental group, the following day. Results showed a Play session effect on oxytocin, where a significant difference was observed for time (Chi-Square = 3.88, DF = 1, p = .05) and for group*time interaction (Chi-Square = 5.65, DF = 1, p = .02): in the Control group, T1 was significantly higher than T0 (p

Numerous studies have shown that providing straw to pigs can reduce undesirable behaviours such as aggression, tail biting and stereotypy. The measurement of various neuromodulators can be helpful in assessing the development of positive behaviours and overall animal welfare. The oxytocin release is frequently linked to positive emotions and positive welfare. It has been suggested that oxytocin modulates the serotoninergic system. This study aims to investigate the potential effect of straw provision in pigs on peripheral levels of oxytocin and serotonin. In total, 18 mini-pigs were involved in an exploratory study conducted in two parallel groups, Enriched (n=10) and Control (n=8) groups. Pigs were divided by group and housed in pens of two individuals. Straw was provided continuously only in Enriched group and renewed each day for 2 weeks. Two blood samples were drawn from each animal 5 to 10 min before providing the straw, and 15 min after providing straw, during the 1st week, to analyse peripheral changes in oxytocin and serotonin before and after straw provision, and determine the existence of a putative short-term effect. The same procedure was carried out for Control group, without straw provision. Long-term effects of straw provision were also examined using blood samples drawn at the same hour from each animal in the 2nd and 3rd weeks. During this time, animals had the permanent possibility to explore the straw in Enriched group but not in Control group. At the end of each week, one animal-keeper completed two visual analogue scales for each mini-pig regarding the difficulty/ease to work with and handle it and its trust in humans. Results showed peripheral oxytocin increases in both groups after 2 weeks (P=0.02). Results did not demonstrate any effect of providing straw to allow exploratory behaviour on peripheral serotonin. Other results were not significant. This preliminary study explored the relationship between peripheral oxytocin and serotonin and the presence of straw that allow pigs to perform exploratory behaviour, suggesting that there was no relationship between them. Some future studies may include crossing oxytocin and serotonin with other parameters, such as behavioural measures, to obtain more information about the true state of the animal and any possible relationship with pig welfare.

Equine-assisted therapies (EATs) have been widely used in the treatment of patients with mental or physical conditions. However, studies on the influence of equine-assisted therapy (EAT) on equine welfare are very recent, and the need for further research is often highlighted. The aim of this study was to investigate whether EAT creates negative or positive emotions in horses, and the influence of patients&rsquo, expectations (one group of patients had physical and psychological expectations and one group of patients had only psychological expectations) on horses&rsquo, emotional responses. Fifty-eight pairs (patient&ndash, horse) were involved in this study. Behaviors and heart rate variability (HRV) data were collected during a resting phase, a preparation phase in which the patients brushed and saddled the horse, and a working phase. Behaviors and HRV were compared between phases and among the groups of patients. Our results suggested that the EAT in this study was neither a negative nor a positive event. EATs with patients who had both physical and psychological expectations were more challenging for horses than those with patients who had only psychological expectations. Further research should focus on providing horses with positive stimulation and reinforcement to understand whether a positive association with EAT can be achieved.

Sequential developmental events, starting from the moment of fertilization, are crucial for the acquisition of animal body plan. Subtle modifications in such early events are likely to have a major impact in later morphogenesis, bringing along morphological diversification. Here, comparing the blind cave and the surface morphotypes ofAstyanax mexicanusfish, we found heterochronies during gastrulation, producing organizer and axial mesoderm tissues with different properties, including differences in expression ofdkk1b, that may have contributed to cavefish brain evolution. These variations observed during gastrulation depend fully on maternal factors, whereas later phenotypic differences in neural development became progressively hidden when zygotic genes take the control over development. Transcriptomic analysis of fertilized eggs from both morphotypes and reciprocal F1 hybrids showed a strong and specific maternal signature. Our work strongly suggests that maternal effect genes and developmental heterochronies occurring during gastrulation have impacted morphological brain change during cavefish evolution.

Chemical cues allow prey to avoid predators without direct contact, which may greatly improve chances of survival, but may be costly if threat is overestimated. Hence, the threat-sensitive predator avoidance hypothesis predicts that prey response to predation threat cues should match the level of danger posed by the predators. While the behavioural response of prey to chemical cues betraying the presence of predators has been observed and well documented in numerous taxa, few studies have been carried out on terrestrial gastropods, despite olfaction being their primary sense. In a previous study, the authors found that the slug Deroceras reticulatum, which inhabits wet environments, responds to chemical cues from specific ground-beetle species. In order to determine whether this observation can be extended to other species of terrestrial gastropods, we examined the response of the xerophilous land snail, Xeropicta derbentina, to the presence of chemical cues from several predacious ground beetles (Carabus auratus, C. auronitens, C. nemoralis, C. coriaceus and C. morbillosus). Only C. morbillosus, a potent snail-eater from sunny habitats, significantly altered the snails’ choice of climbing area whereas, in another experiment, it did not modify the shelter choice of the slug D. reticulatum. These results are consistent with a species-specific perception of predation threat in terrestrial gastropods, which may be based on a combination of ecological and biological features in both predator and prey.

International audience; Benzopyridothiadiazepine (2a) and benzopyridooxathiazepine (2b) were modified to produce tricyclic quinazolinone 15–18 or benzothiadiazine 26–27 derivatives. These compounds were evaluated in cytotoxicity and tubulin inhibition assays and led to potent inhibitors of tubulin polymerization. N-[2(4-Methoxyphenyl)ethyl]-1,2-dihydro-pyrimidino[2,1-b]quinazolin-6-one (16a) exhibited the best in vitro cytotoxic activity (GI50 10–66.9 nM) against the NCI 60 human tumor cell line and significant potency against tubulin assembly (IC50 0.812 μM). In mechanism studies, 16a was shown to block cell cycle in G2/M phase and to disrupt microtubule formation and displayed good antivascular properties as inhibition of cell migration, invasion, and endothelial tube formation. Compound 16a was evaluated in C57BL/6 mouse melanoma B16F10 xenograft model to validate its antitumor activity, in comparison with reference ABT-751 (1). Compound 16a displayed strong in vivo antitumor and antivascular activities at a dose of 5 mg/kg without obvious toxicity, whereas 1 needed a 10-fold higher concentration to reach similar effects.

International audience; Chemicals are the major means of control used against slugs, which are serious pests of various crops. To increase the sustainability of farming practices, alternatives that do not harm nontarget organisms are necessary. One area of investigation focuses on the capacities of prey to perceive their predators, which enables them to display antipredator behaviours. This study presents initial evidence of the potential effectiveness of using chemical cues from a predatory ground beetle to protect young oilseed rape shoots against a worldwide pest, the slug Deroceras reticulatum (Muller, 1774) (Stylommatophora: Agriolimacidae). A two-choice assay was used to test whether chemical cues from Carabus nemoralis Muller, 1764 (Coleoptera: Carabidae) could impede the foraging of D. reticulatum on young oilseed rape shoots. Significantly fewer cotyledons were consumed when chemical cues from the ground beetle were present compared with the control area, where slugs were mainly found. Chemical cues from predatory ground beetles appear to be a promising solution for protecting at-risk crops from the depredations of pest slugs.

A series of 1-phenyl-[1,2,4]triazolo[4,3-a]quinazolin-5-ones designed as conformationally restricted CA-4 analogues, were tested for their tubulin polymerization and growth inhibitory activities. The 3-hydroxy-4-methoxy derivatives 11d and 12d are potent inhibitors of tubulin assembly but only the N-methylated amid counterpart 12d possesses potent anticancer activity in a large panel of cancer cell lines. Upon treatment with compound 12d, remarkable cell shape changes as cell migration and tube formation were elicited in HUVECs, consistent with vasculature damaging activity.

The intramolecular Mannich-type reaction of quinazoline derivatives with aldehydes provides diastereomeric mixtures of imidazoquinazoline-9-ones.