Impaired Reflex Research Articles

Pathogenicity of CsRV2 and CdPBV1 in Callinectes danae: An Imminent Concern for Crab Production in Brazil.

Understanding the pathogenicity of viral infections in aquatic organisms is vital due to their substantial impact on aquaculture and wild populations. This study assessed the pathogenicity of Callinectes sapidus Reovirus 2 in Callinectes danae and its effects on the metabolic, immunological and behavioural parameters. CsRV2-negative specimens were divided into CsRV2 inoculum (n = 10) and saline injection (n = 15). After 14 days, all the crabs that received the inoculum tested positive for CsRV2. However, 11 crabs from the control group also tested positive and were subsequently considered an additional experimental group. The cumulative mortality in the group challenged reached 70% after 14 days. RT-PCR revealed Callinectes danae Portunibunyavirus 1 presence in CsRV2-injected crabs, explaining heightened mortality. Ammonia flow remained unaffected, but oxygen consumption was significantly impacted (p < 0.05) by CsRV2 and coinfection, suggesting increased metabolic energy expenditure. The coinfection caused an increase in the proportion of crabs with reflex impairment as a likely consequence of physiological exhaustion. Additionally, there was a trend toward reducing the number of granulocytes in coinfected crabs, indicating that granulocytes may be more affected by coinfection. These findings demonstrate the pathogenicity of CsRV2 in C. danae, with coinfection exacerbating metabolic, behavioural and immunological changes, increasing mortality.

Short-term discard survival and catch-related trauma in European plaice (Pleuronectes platessa) caught in the Baltic Sea by Danish seine during summer

Danish seine is an active fishing gear targeting demersal species, such as European plaice (Pleuronectes platessa, hencefort referred as plaice), a commercially important fish species in the North Sea, Skagerrak, Kattegat, and Baltic Sea. Danish seining is a relevant fishery in relation to exemption from the European Union landing obligation. Trials were conducted from a commercial fishing vessel during the summer with high air temperatures and sea salinity and marked salinity and temperature gradients (pycnocline). Video equipment was used to observe fish entering the seine. Captured fish were individually tagged and housed in livewells for ten days to observe short-term survival. Reflex impairments and external injuries were assessed after capture and at the end of the observation periods using reflex action mortality predictor (RAMP) and catch-damage index (CDI) methodologies. We found that plaice entered the seine late in the towing process and that 87 % of the assessed fish survived, after 10 days of observation. There was a significant difference in short-term survival curves for fish that had been subjected to more than 30 min of on-deck during the catch-sorting process relative to those that had remained on deck for 30 min or less. The association between the time on deck and RAMP scores after capture was also significant. External injuries were primarily minor bruises, fin fraying, and net marks and changed little from after capturing to the end of the observation period.

Prediction of Cerebral Palsy and Other Motor Developmental Trajectories in High-Risk Neonate Using the Rapid Neurodevelopmental Assessment (RNDA)

Background: Cerebral Palsy (CP) is a prevalent motor disability affecting children globally, emphasizing the need for early identification and intervention. The Rapid Neurodevelopmental Assessment (RNDA) offers a comprehensive approach to predict CP and other motor developmental trajectories in high-risk neonates. Objective: This longitudinal cohort study aims to evaluate the effectiveness of RNDA in predicting CP and motor developmental trajectories. Method: Seventy term neonates from Dhaka Shishu (Children) Hospital were included, with neurodevelopmental assessments conducted using RNDA. Assessments were performed at 3 months and 6-9 months, with CP evaluation at 12 months using clinical examinations. Results: Prolonged labor (44.3%) and delayed cry after birth (31.4%) were common among the study patients (n=70), with varying modes of delivery including normal vaginal delivery (50.0%), vaginal delivery with complications (12.9%), and lower uterine cesarean section (37.1%). Muscle tone, primitive reflexes, gross and fine motor skills, epilepsy, and microcephaly were evaluated across visits to identify impending CP. Significant associations were found between hypertonicity, primitive reflex impairment, gross motor impairment, and fine motor impairment with impending CP across visits, particularly in the 3rd visit (p&lt;0.05). Sensitivity, specificity, accuracy, and predictive values varied across parameters and visits, with fine motor skills and gross motor skills showing the highest sensitivity in the 3rd visit (86.4% and 100.0%, respectively). Additionally, abnormal EEG, USG of the brain, and MRI findings were significantly associated with impending CP, with USG of the brain demonstrating the highest sensitivity (93.3%) and MRI showing the highest specificity (70.0%). Conclusion: RNDA emerges as a valuable tool for early prediction of CP and motor developmental trajectories in high-risk neonates. Early identification through RNDA facilitates timely interventions, optimizing long-term neurodevelopmental outcomes.

Partial sensory rhizotomy in recurrent trigeminal neuralgia. Our experience and literature review

Background and objectiveTrigeminal Neuralgia (NT) is a common pathology in Neurosurgery. It can be classified as idiopathic or secondary to other pathologies, such as Multiple Sclerosis (MS). Several surgical treatments have been described, some of them being replaced by more modern techniques. Partial sensory rhizotomy (PSR), described by Dandy is a technique replaced by other techniques due to its permanent side effects. We present our experience with this technique in patients with recurrent NT. Methods and materialsA retrospective review is carried out on five patients who underwent surgery at our center from 2018 to 2023 using the PSR technique. ResultsAll the patients intervened showed significant clinical improvement, except one patient who required reintervention due to uncontrolled pain. According to the Barrow Neurological Institute (BNI) scale, 80% (4/5) of patients showed improvement from grade V to grades I/II except for one of them. This patient suffered from MS. Additionally, one patient presented a corneal ulcer after surgery due to impairment of the corneal reflex. ConclusionIn our experience, PSR is a valid treatment option in selected patients with recurrent TN. It has a low incidence of complications with an adequate surgical technique and anatomical knowledge of the region. To the best of our knowledge, we are one of the few centers in Spain to publish our results with PSR in the last ten years. We report good results in pain control withdrawing medication in 80% (4/5) of the operated patients.

Impact of hook choice, fish size, and water temperature on hooking depth, injury, and postcapture physiology in Channel Catfish

AbstractObjectiveCatch‐and‐release angling is an oft‐practiced conservation tool involving the release of captured game fish either due to harvest regulations or conservation ethic on the part of the angler. Central to this practice is the assumption that released fish survive; however, a large body of work has shown that postrelease mortality can occur, especially if fish are injured during the capture process. In this study, we examined hooking location, bleeding, injury rates, and postcapture physiology in Channel Catfish Ictalurus punctatus, a popular game fish species.MethodsA total of 83 Channel Catfish were angled from a lake in southern Illinois using conventional rod‐and‐reel techniques with one of four hook types (J‐hook, shiner, circle, and octopus). Captured fish were then assessed for hooking depth, bleeding, and injury. Subsequently, a subset of 40 fish were additionally held for 4 h in submerged totes before being tested for reflex responsiveness and undergoing a blood biopsy for glucose and lactate levels.ResultCircle and octopus hooks reduced hooking depth in Channel Catfish compared with J‐hooks and tended to reduce postcapture bleeding as well. Postholding physiological results showed no effect of hook type on blood lactate or glucose levels, and reflex impairment was very rare (only a single fish was impaired for any reflexes 4 h postcapture).ConclusionOverall, the results of this study suggest that the use of circle hooks reduce the likelihood of deep hooking and injury in Channel Catfish, though Channel Catfish, at least in the short term, were physiologically resilient to the effects of capture.

La rizotomía parcial sensitiva en la neuralgia del trigémino recurrente. Nuestra experiencia y revisión de la literatura

Background and objectiveTrigeminal neuralgia (NT) is a common pathology in neurosurgery. It can be classified as idiopathic or secondary to other pathologies, such as multiple sclerosis (MS). Several surgical treatments have been described, some of them being replaced by more modern techniques. Partial sensory rhizotomy (PSR), described by Dandy, is a technique replaced by other techniques due to its permanent side effects. We present our experience with this technique in patients with recurrent NT. Methods and materialsA retrospective review is carried out on five patients who underwent surgery at our center from 2018 to 2023 using the PSR technique. ResultsAll the patients intervened showed significant clinical improvement, except one patient who required reintervention due to uncontrolled pain. According to the Barrow Neurological Institute (BNI) scale, 80% (4/5) of patients showed improvement from gradeV to gradesI/II except for one of them. This patient suffered from MS. Additionally, one patient presented a corneal ulcer after surgery due to impairment of the corneal reflex. ConclusionIn our experience, PSR is a valid treatment option in selected patients with recurrent TN. It has a low incidence of complications with an adequate surgical technique and anatomical knowledge of the region. To the best of our knowledge, we are one of the few centers in Spain to publish our results with PSR in the last ten years. In our study, we report good results in pain control withdrawing medication in 80% (4/5) of the operated patients.

Neuromolecular mechanisms related to reflex behaviour in Aplysia are affected by ocean acidification.

While ocean acidification (OA) impacts the behaviour of marine organisms, the complexity of neurosystems makes linking behavioural impairments to environmental change difficult. Using a simple model, we exposed Aplysia to ambient or elevated CO2 conditions (approx. 1500 µatm) and tested how OA affected the neuromolecular response of the pleural-pedal ganglia and caused tail withdrawal reflex (TWR) impairment. Under OA, Aplysia relax their tails faster with increased sensorin-A expression, an inhibitor of mechanosensory neurons. We further investigate how OA affects habituation training output, which produced a 'sensitization-like' behaviour and affected vesicle transport and stress response gene expression, revealing an influence of OA on learning. Finally, gabazine did not restore normal behaviour and elicited little molecular response with OA, instead, vesicular transport and cellular signalling link other neurotransmitter processes with TWR impairment. Our study shows the effects of OA on neurological tissue parts that control for behaviour.

An assessment of post-capture condition and survival of Rajidae caught in fixed nets

Skates (Rajiformes: Rajidae) are commercially and ecologically-important elasmobranchs captured in targeted and mixed fisheries globally. Many species are of conservation concern and are subject to high levels of discarding. They are currently exempt from the European Union’s landing obligation due to evidence of high discard survival, although the bulk of this evidence comes from mobile gear fisheries. Improved evidence on survival after discarding from fixed gears is necessary. We assessed immediate survival rates and post-capture condition (injury, reflex impairment, and vitality) of four skate species commonly discarded from seasonal Dover sole, Solea solea and plaice, Pleuronectes platessa gillnet fisheries in the Irish Sea and Bristol Channel, UK. We also modelled the relationship between a suite of environmental and operational fishing variables to the condition of thornback skate, Raja clavata. This is the dominant skate captured as bycatch and is classified as near threatened by the IUCN due to declining populations trends. At-vessel survival on gear hauling was high for all species (R. clavata = 99.43%, R. montagui = 100%, R. microocellata = 100%, R. brachyura = 100%). Post-capture condition of R. clavata was size-dependent, with larger skates demonstrating higher levels of injury and reflex impairment and poorer vitality. Higher vitality in smaller individuals and strong negative effects of aerial exposure on skate vitality highlight the likely benefits of prioritising discarding of unwanted catch upon gear hauling. This may maximise survival and future reproductive potential and facilitate population recovery.

The Degree of Cardiovascular Autonomic Dysfunction is not Different in GBA-Related and Idiopathic Parkinson's Disease Patients: A Case-Control Instrumental Evaluation.

Increased prevalence of cardiovascular autonomic failure might play a key role on Parkinson's disease (PD) progression of glucocerebrosidase gene (GBA)-mutated patients, determining a malignant phenotype of disease in these patients. To objectively characterize, for the first time, the cardiovascular autonomic profile of GBA-mutated patients compared to idiopathic PD patients by means of cardiovascular reflex tests (CRTs). This is a case-control (1 : 2) study on PD patients belonging to well-characterized prospective cohorts. For each PD patient carrying GBA variants, two idiopathic PD patients, matched for sex and disease duration at CRTs, were selected. Patients recruited in these cohorts underwent a complete clinical and instrumental evaluation including specific autonomic questionnaires, CRTs and extensive genetic analysis. A total of 23 GBA-PD patients (19 males, disease duration 7.7 years) were included and matched with 46 non-mutated PD controls. GBA-mutated patients were younger than controls (59.9±8.1 vs. 64.3±7.2 years, p = 0.0257) and showed a more severe phenotype. Despite GBA-mutated patients reported more frequently symptoms suggestive of orthostatic hypotension (OH) than non-mutated patients (39.1% vs 6.5%, p = 0.001), the degree of cardiovascular autonomic dysfunction, when instrumentally assessed, did not differ between the two groups, showing the same prevalence of neurogenic OH, delayed OH and cardiovascular reflex impairment (pathological Valsalva maneuver). GBA-PD patients did not show different instrumental cardiovascular autonomic pattern than non-mutated PD. Our findings suggested that symptoms suggestive of OH should be promptly investigated by clinicians to confirm their nature and improve patient care and management.

Sex and season influence behaviour and physiology of lake trout following angling.

Catch-and-release angling exposes fish to challenges that may result in sub-lethal effects or mortality. Lake trout (Salvelinus namaycush) undergo high rates of release because of size-based harvest regulations or voluntary angler behaviour. Here, we examine short-term impairment in lake trout angled during the summer (n = 74) and fall spawning period (n = 33) to inform best practices for angling. Immediately following capture or 0.5h post-capture, fish underwent reflex and barotrauma assessments, and a small blood sample was collected. Fish were also fitted with an externally mounted biologger equipped with depth, temperature and tri-axial acceleration sensors, that was tethered to allow retrieval of the logger after 14min. In the summer, reflex impairment and barotrauma at 0 and 0.5h were significantly correlated. Loss of orientation and bloating were the most observed indicators. Larger fish and those captured at increased depth had higher barotrauma scores, while prolonged fight times decreased the barotrauma score regardless of sampling time. Plasma cortisol, lactate and glucose increased 0.5h after capture, and extracellular and intracellular pH decreased, all signs that angling was inducing a metabolic response. However, no relationships were found between blood indices and mortality (18.9%). The time required to reach maximum depth after release was longer for fish with increased air exposure but shorter for those with longer fight times. During the fall, fish displayed no mortality or reflex impairment. Anal prolapse was the most observed indicator of barotrauma but only observed in females. Blood indices were most altered 0.5h after capture, with increased cortisol values for fish that were female, particularly large or captured at deeper depth. Locomotor activity was highest for males and increased with depth. Together, our findings suggest that the effects of catch-and-release angling may be dependent on several factors, including sex, season and angling depth.

Optimizing the prediction of discard survival of bottom-trawled plaice based on vitality indicators.

Predicting the discard survival of aquatic animals after fisheries capture using vitality indicators (i.e. individual scores or indices of physical condition) is a resource-efficient approach compared to estimating discard survival from captive observation. But such indicators do not always lead to accurate and robust predictions. Individual scores of reflex impairments and injuries are typically given the same weight when being aggregated into an index, while some reflexes or injuries may contribute to mortality more than others. This study established an analytical methodology and created an index based on differential contributions of individual reflexes and injuries to optimize the prediction of discard survival of bottom-trawled European plaice (Pleuronectes platessa). The optimization procedures were applied to a dataset from vitality assessment of 1122 undersized plaice caught during 16 commercial fishing trips and 58 gear deployments in Belgium and Denmark. As welfare indicators, we considered and evaluated against post-capture survival of plaice: original vs. optimized reflex impairment and injury (R&I) index, number of absent reflexes, number of present injuries, number of absent reflexes and present injuries, categorical vitality score and individual reflex and injury scores. These were used in eight candidate generalized linear models (one without any vitality indicator) as explanatory variables to predict survival, with or without biological, environmental, technical and operational covariates, either at the individual fish or trip level. Bruising to the head and body were the most relevant predictors. The optimized R&I index did not perform better than any other vitality indicator, and all the indicators performed poorly in predicting survival probability both at the fish and trip levels without information on air exposure and seawater temperature. This means that they cannot be considered to be independent measures. The categorical vitality score provided a viable alternative to the more labour-intensive, scoring method of reflex responsiveness. Use of reflexes as proxies may not be accurate when they are not independent of environmental, biological or technical variables.

Usefulness of eye tracking systems in multiple sclerosis

Multiple sclerosis (MS) is a chronic disease of the central nervous system characterized by inflammation and neurodegeneration. It represents the leading cause of nontraumatic disability in young adults in many places around the world.Currently, for the objective quantification of the damage of the visual pathway swept‐source OCT (SS‐OCT) is considered the most appropriate technique. Additionally, during the course of the disease multiple neurological deficiencies can appear, including eye motility disorders.Patients may develop various ocular motor disorders (OMDs) affecting visual function and significantly increasing disability. These alterations involve visual function and may decrease quality of life perceived by patients because they affect, among other functions, reading capability.OMDs, can be analysed by several recording systems, although they have not been incorporated into the practice routine clinic due to its complexity, high costs and also because the value of these alterations is probably not known.It is possible that an accurate examination of motility eye, may have a substantial impact on the diagnosis and management of those patients. OMDs has been suggested as potential biomarker of early neurological deterioration and its evaluation could contribute to obtaining progression and response to treatments, facilitating translational development of so‐called precision medicine.Eye trackers are state‐of‐the‐art tools that can obtain valuable information of OMDs in neurological degenerations. In MS, oculomotor alterations as saccadic dysmetria, saccadic intrusions, nystagmus, fixational deficits, smooth pursuit impairment, skew deviation, optokinetic and vestibulo‐ocular reflex impairments, may go unnoticed because systematic examination of the oculomotor systems do not use routinely these techniques.As mentioned, objective recordings of eye movements through eye‐tracking systems are not currently performed widely, despite that they have been described as an important adjunct in diagnosis, documentation, and management of different neurologic conditions.In addition, eye tracking is also a capable method to investigate the relationship between behaviour and neural mechanisms. Eye motion recordings provide a measure of functional preservation of the nervous system, which should be recognized to be of significant importance in assessing a disease in which disability is manifested by disruption of normal neuronal functions.In fact, it has been described that eye tracking tasks (especially saccadic tasks) are often used as an adjunct to traditional scales for cognitive assessment. In addition, eye tracking data confirmed that MS is characterized by attention deficits.In conclusion, there is a growing interest in the use of eye tracking systems as biomarkers for MS. Specifically in this work we have analysed a large series MS patients to detect if any of the anomalies that patients refer to, such as reading difficulties, are related to disorders of the ocular motor systems.

The role of temperature in vitality and survival assessments of beam-trawled and discarded European plaice (Pleuronectes platessa).

Thermal stress can influence the recovery of fish released after capture. Vitality assessments using reflex and behavioural responses require that responses can be observed reliably, independent of temperature. Here, we tested whether reflex and behavioural impairment and survival of beam-trawled and discarded European plaice (Pleuronectes platessa) are independent from seasonal air and water temperature deviations. In total, 324 beam-trawled plaice (n = 196 in summer and n = 128 in winter) were exposed to two air temperature treatments and two water treatments (i.e. modified and ambient temperatures for both). The modified treatments (i.e. cooled in summer, warmed in winter) represent the thermal shock a fish may experience when being returned to the water. All reflexes and tested behaviours were affected by ambient temperature, with high impairment noted in summer. None of the reflexes were affected by temperature shocks alone, only body flex was. Body flex was highly impaired under every exposure combination. Fish size and duration of air exposure further influenced impairment of reflexes such as head complex and tail grab. More generally, post-release survival was assessed as 21% [95% CI: 16-28%] in summer and 99% [97-100%] in winter. Beam trawling in summer is likely to induce high reflex impairment and mortality in discarded plaice, and therefore spatial-temporal mitigation approaches should be prioritized over control of on-board temperatures.

Influence of four hook types across four hook removal tools, including bare hands, on the effectiveness of hook removal and reflex impairment of Bluegill (Lepomis macrochirus) captured from a lake in Eastern Ontario

AbstractHook removal devices have been developed to enable rapid release of angled fish, yet little research has evaluated their effectiveness and potential for injury among hook types. We compared the performance of hook removal tools and bare hands with four hook types on freshwater Lepomid sunfish. Dehooking performance was assessed using hook removal time, unhooking difficulty, degree of tissue damage at the hooking location, and immediate reflex impairment. Unhooking difficulty was positively related to hooking depth. Unhooking difficulty was lowest for hemostats and the mechanical dehooking device; however, the mechanical dehooking device caused the largest tearing of mouth tissue. Unhooking difficulty was the main driver for hook removal time, tissue tear length, and overall reflex impairment. Hooks that were harder to remove caused higher reflex impairment. Hook type had little influence on the effectiveness of hook removal tools, although circle hooks were more difficult to remove and caused greater injury when using tools. Although use of hook removal tools can be beneficial for fish that are released, more research is needed on more species targeted by recreational anglers, and more hook removal tools. We suggest that hemostats should be used to remove hooks from fish to reduce unhooking difficulty, tissue tears, long air exposure, and thereby to increase the welfare of the fish.

Vagus nerve SARS-CoV-2 infection and inflammatory reflex dysfunction: Is there a causal relationship?

Autonomic dysfunction is a clinical hallmark of infection caused by SARS-CoV-2, but the underlying mechanisms are unknown. The vagus nerve inflammatory reflex is an important, well-characterized mechanism for the reflexive suppression of cytokine storm, and its experimental or clinical impairment facilitates the onset and progression of hyperinflammation. Recent pathological evidence from COVID-19 victims reveals viral infection and inflammation in the vagus nerve and associated nuclei in the medulla oblongata. Although it has been suggested that vagus nerve inflammation in these patients mediates dysregulated respiration, whether it also contributes to dysfunction of the vagus nerve inflammatory reflex has not been addressed. Because lethality and tissue injury in acute COVID-19 are characterized by cytokine storm, it is plausible to consider evidence that impairment of the inflammatory reflex may contribute to overproduction of cytokines and resultant hyperinflammatory pathogenesis. Accordingly, here the authors discuss the inflammatory reflex, the consequences of its dysfunction in COVID-19, and whether there are opportunities for therapeutic intervention.

Condition and postrelease mortality of angled Northern Pike temporarily retained on stringers

AbstractObjectiveAnglers typically use stringers to keep fish intended for harvest from spoiling or for high‐grading purposes (i.e., culling). However, relatively few studies have examined the effects of temporary stringer retention on the physical condition and postrelease mortality of fish. In this study, our objective was to investigate the lethal and sublethal effects of temporarily retaining Northern Pike Esox lucius on stringers.MethodsWe evaluated the blood physiology, reflex impairment, injury, and fate of 168 Northern Pike that were exposed for 2 h on one of five treatments: (1) cord stringer through the operculum, (2) cord stringer through the lower jaw, (3) metal stringer through the operculum, (4) metal stringer through the lower jaw, and (5) aerated tank control.ResultImmediately after retention, blood lactate concentrations of stringer treatments were on average 42% greater relative to controls. Fish from the stringer treatments exhibited injuries of varying severity, most of which (e.g., gill lesions, expanded puncture wounds, swelling) were still present on surviving fish 48 h later. Reflexes were impaired for all stringer fish, whereas control fish tended to have all reflexes intact. No fish died during the treatment period. The highest occurrence of mortality was within the first 8 h following retention for the cord–operculum (48%), metal–jaw (15%), and metal–operculum (19%) treatments. Stringers placed through the operculum had a higher mortality rate (37%) compared with stringers placed through the lower jaw (17%), regardless of stringer type. Overall, 27% of fish placed on stringers died and 68% of the remaining fish showed injuries related to stringers, while control fish showed low mortality (7%) and no meaningful injuries.ConclusionOur results suggest that holding fish on stringers causes stress and injury levels that can result in postrelease mortality. As such, fisheries managers should consider restricting the release of fish placed on stringers, and once placed on a stringer, fish should be regarded as part of the daily harvest limit for a given angler.

Lake trout reflex impairment and physiological status following ice-angling

We examined behaviour and physiology of lake trout ( Salvelinus namaycush) following ice-angling. Fish were ice-angled and placed in a water-filled tub for 0.5, 4, and 6 h to recover ( n = 19). Reflex impairment and physiological status were assessed repeatedly for every individual. Longer fight times lead to higher lactate and glucose, and lower extracellular pH 0.5 h post-angling. Loss of orientation was the most common reflex impairment (84% of fish) 4 h post-angling. Mortality (36.8%) was observed during the study; however, variation in handling, barotrauma, and issues with sampling may have confounded angling effects. To determine if barotrauma impacted impairment and mortality, lake trout at a later sampling date ( n = 29) were exposed to air for either 60, 120, 180, 240, 300, or 420 s before assessment (3.4% mortality). For fish air-exposed for 300 s or more, 14% lost orientation during immediate assessment. Bloating occurred in 20% of fish air-exposed for 60 s. An air exposure duration of 420 s significantly impaired reflexes. Recreationally caught lake trout show behavioural and physiological impairment with such impairments magnified by extended air exposure.

Effect of different diets on growth performance, physiological response and behavior of spiny lobster Panulirus homarus (Linnaeus, 1758)

This study aimed to know the effect of different feedings on growth performance, physiological responses, and behavioral changes of juvenile spiny lobsters. The experimental method used a completely randomized design with three treatments and four replications. There were three different feeds used as treatment, namely: flesh mussel (K), commercial fish feed (I), and commercial shrimp feed (U). Feed is given as much as 30% of body weight, five times per day at 6:30 am, 12:00 pm, 4:00 pm, 9:00 pm, and 2:00 am. The results showed that the commercial feeding of fish (I) significantly (P&lt;0.05) increased the survival rate and biomass of spiny lobster for 54.17% and 141.7 g, respectively. While fresh mussel give better growth and stress response, but had the lowest survival rate. The results of the physiological response test of lobster were more effective in suppressing lobster stress levels than other treatments (P&lt;0.05). The behavior of juvenile spiny lobsters showed a very striking color difference and reflex impairment scores, which indicated that the vitality of the treated juveniles (I) was better than the vitality of the treatments (K) and treatment (U). This study shows that commercial fish feed (I) is recommended for maintaining spiny lobsters in the juvenile phase, although it needs further maintenance by using an appropriate feed formulation to improve the growth performance of spiny lobsters.

Salinity and temperature affect the symbiont profile and host condition of Florida USA blue crabs Callinectes sapidus

Subtropical Florida blue crabs, Callinectes sapidus, exhibit differing life history traits compared to their temperate counterparts, likely influencing symbiont infection dynamics. Little information exists for Florida C. sapidus symbiont profiles, their distribution among various habitats, and influence on crab condition. Using histopathology, genomics, and transmission electron microscopy, we describe the first symbiont profiles for Florida C. sapidus occupying freshwater to marine habitats. Twelve symbiont groups were identified from 409 crabs including ciliophorans, digenean, microsporidian, Haplosporidia, Hematodinium sp., Nematoda, filamentous bacteria, gregarine, Callinectes sapidus nudivirus, Octolasmis sp., Cambarincola sp., and putative microcell. Overall, 78% of C. sapidus were documented with one or more symbiont groups demonstrating high infection rates in wild populations. Environmental variables water temperature and salinity explained 48% of the variation in symbiont groups among Florida habitats, and salinity was positively correlated with C. sapidus symbiont diversity. This suggests freshwater C. sapidus possess fewer symbionts and represent healthier individuals compared to saltwater populations. Crab condition was examined using the reflex action mortality predictor (RAMP) to determine if reflex impairment could be linked to symbiont prevalence. Symbionts were found positively correlated with crab condition, and impaired crabs were more likely to host symbionts, demonstrating symbiont inclusion may boost predictive ability of the RAMP application. The microsporidian symbiont group had a particularly strong effect on C. sapidus reflex response, and impairment was on average 1.57 times higher compared to all other symbiont groups. Our findings demonstrate the importance of considering full symbiont profiles and their associations with a spatially and temporally variable environment to fully assess C. sapidus population health.

Prepulse inhibition of the acoustic startle reflex impairment by 5-HT2A receptor activation in the inferior colliculus is prevented by GABAA receptor blockade in the pedunculopontine tegmental nucleus

The relationship between serotonin dysfunction and schizophrenia commenced with the discovery of the effects of lysergic acid diethylamide (LSD) that has high affinity for 5-HT2A receptors. Activation of these receptors produces perceptual and behavioural changes such as illusions, visual hallucinations and locomotor hyperactivity. Using prepulse inhibition (PPI) of the acoustic startle, which is impaired in schizophrenia,we aimed to investigate:i) the existence of a direct and potentially inhibitory neural pathway between the inferior colliculus (IC) and the pedunculopontine tegmental nucleus (PPTg) involved in the mediation of PPI responses by a neural tract tracing procedure;ii) if the microinjection of the 5-HT2A receptors agonist DOI in IC would activate neurons in this structure and in the PPTg by a c-Fos protein immunohistochemistry study;iii) whether the deficits in PPI responses, observed after the administration of DOI in the IC, could be prevented by the concomitant microinjection of the GABAA receptor antagonist bicuculline in the PPTg.Male Wistar rats were used in this study. An IC-PPTg reciprocated neuronal pathway was identified by neurotracing. The number of c-Fos labelled cells was lower in the DOI group in IC and PPTg, suggesting that this decrease could be due to the high levels of GABA in both structures. The concomitant microinjections of bicuculline in PPTg and DOI in IC prevented the PPI deficit observed after the IC microinjection of DOI. Our findings suggest that IC 5-HT2A receptors may be at least partially involved in the regulation of inhibitory pathways mediating PPI response in IC and PPTg structures.