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Purpose: To study the characteristics of reflex blink evoked by cold and heat stimulation of the ocular surface (OS), and to define the contribution of TRPM8 to the process. Methods: The orbicularis oculi muscle electromyography signal (OOemg) and the ocular surface temperature (OST; measured with a small thermoprobe placed on the cornea) were recorded in anaesthetised rats. OS temperature changes (ΔT) were induced by topical instillation of 20 μL drops of saline solution at different temperatures (15–50°C). ΔT and the area under the curve (AUC) and duration of the evoked OOemg signals were analysed before (control) and after topical treatment with the TRPM8 antagonist N‐(3‐aminopropyl)‐2‐[(3‐methylphenyl) methoxy] ‐N‐(2‐thienylmethyl) benzamide hydrochloride (AMTB; 1 mM). Results: Mild (−ΔT 0.1–5°C) and intense (−ΔT 5–15°C) cooling always evoked a reflex OOemg signal (probability = 1). AMTB significantly reduced the probability of cooling to evoke blink (probability = 0.26 and 0.57 for mild and intense cold stimuli, respectively; p < 0.001). OOemg AUC and duration were also significantly reduced by AMTB (p < 0.01). Probability of evoking OOemg signal by mild (ΔT 0.1–5°C) and intense (ΔT 5–15°C) OS heating was low (0.30 and 0.59 respectively), and their duration and AUC were significantly smaller than those evoked by cooling (p < 0.001). Although AMTB did not modify the probability of heating stimuli to evoke OOemg signals (0.17 and 0.57 for mild and intense heating, respectively), the duration of signals evoked by mild heating stimuli was significantly increased (p < 0.001). Conclusions: Cold stimuli applied to the ocular surface always evoked reflex EMG activity of the lid muscle. This ability of cooling stimuli to evoke reflex blink is mediated by TRPM8 channels, whose pharmacological blockade reduces both the probability to evoke the reflex blink and its amplitude. Support: PID2020‐115934RB‐I00 from DOI: MCIN/AEI/10.13039/50110001103; CIPROM/2021/48 from Generalitat Valenciana, Spain. [ABSTRACT FROM AUTHOR]

This work reports for the first time the presence and molecular characterization of Eimeria myoxi in the garden dormouse (Eliomys quercinus) from the Doñana Natural Area (Andalusia, SW Spain). Fresh faecal samples were collected from a total of 28 garden dormice, which were caught following current guidelines for the ethical use of animals in research, and processing by a standard flotation technique with saturated saline solution. Then, wet drops were examined microscopically, and the number of oocysts was semi-quantified. Eimeria oocysts were observed in 16 of the 28 (57.1%) faecal samples, showing most of them a very low number of oocysts (≤1 oocyst per microscopic field × 400). The unsporulated oocysts visualized in 16 faecal samples were subspherical and of length 19.2 ± 1.2 μm and width 17.4 ± 1.1 μm, being morphologically compatible with E. myoxi. This finding was supported by molecular analysis of the small subunit ribosomal RNA (SSU-rRNA) gene, identifying the same species in 22 of the 28 (78.6%) dormice, including 15 samples in which oocyst size was compatible with E. myoxi. Moreover, the subsequent analyses of the apicoplast open reading frame 470 (ORF470) and the mitochondrial cytochrome c oxidase subunit I (COI) genes confirmed the molecular identification of the isolates as E. myoxi. The phylogeny analyses were consistent with previous phylogenetic studies and support the existence of three lineages of rodent-infecting Eimeria species. [Display omitted] • Eimeria myoxi was identified in Eliomys quercinus in Spain for the first time. • Microscopic and molecular analysis revealed a high prevalence of Eimeria myoxi. • More evidence was obtained supporting the three lineages of Eimeria in rodents. [ABSTRACT FROM AUTHOR]

Sympatric closely-related species co-occur within heterogeneous environments by occupying separate ecological niches as result of adaptive differentiation. Soil salinity is one of the most relevant drivers leading plant zonation in salt marshes, where germination is a critical stage in the life cycle of many halophytes. Salinity influence on germination patterns was evaluated for six sympatric Limonium species (L. admirable, L. caesium , L. cossonianum , L. delicatulum , L. supinum and L. tobarrense), which grow under arid environmental conditions in an inland salt marsh from the southeastern Spain. Experiments were conducted to determine the effects of different salinities (0–6% NaCl) on seed germination under 12 h in light at 25 °C and for 12 h in dark at 20 °C. Best seed germination was obtained under non-saline conditions, and germination was delayed and significantly reduced by increasing the salinity levels for all the studied taxa. The germination variables related to final germination percentage, mean time to germination and recovery were directly influenced by salinity. Seeds recovered their germination capacity after transferring the seeds from saline solutions to distilled water, especially those seeds previously treated under high salinity conditions. Our results suggest that the successful establishment of Limonium communities depends on the germination strategy which implies a rapid germination velocity when the soil salinity decreases. Two different germination syndromes based on germination percentage and germination recovery have been found. Hence, these germination strategies would favour the adaptation of different Limonium species under favorable conditions, shaping the plant asssembly within the saline habitat. [Display omitted] • The successful establishment of Limonium communities depends on the rapid germination velocity when the soil salinity decreases. • Two different germination syndromes based on germination percentage and germination recovery appear on the Limonium morphotypes. • Germination strategies favour the Limonium species adaptation under favorable conditions, establishing the ecological assembly. [ABSTRACT FROM AUTHOR]