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We investigated dominance in two groups of captive painted turtles, each over a period of 8 weeks. In each case, we began with five turtles, then added a sixth after 6 weeks. One group was run in the fall, the other in the spring, and the makeup of males and females differed in the two seasons. We measured two behaviors while they were feeding: mounting, defined as placing a claw or head above the carapace of the other turtle for at least one second, where the mounter was stationary, and biting, defined as snapping at another turtle. We hypothesized that the turtles would demonstrate a dominance hierarchy. Our results showed that painted turtles show individual differences in behavior. These differences are consistent over time and allow dominance hierarchies to be established. Both mounting and biting demonstrated consistency, but mounting was more consistent than biting. The amount of mounting and biting differed by sex and season, but turtle size did not seem to influence their activities. Finally, the introduction of a new turtle disrupted the dominance behaviors of the turtles, suggesting that turtles recognize a new turtle as unfamiliar. Understanding the complex dynamics of captive turtle populations has implications for the management and welfare of turtles in captivity and in the wild.

The mammalian skull is very malleable and has notably radiated into highly diverse morphologies, fulfilling a broad range of functional needs. Although gnawing is relatively common in mammals, this behavior and its associated morphology are diagnostic features for rodents. These animals possess a very versatile and highly mechanically advantageous masticatory apparatus, which, for instance, allowed caviomorph rodents to colonize South America during the Mid‐Eocene and successfully radiate in over 200 extant species throughout most continental niches. Previous work has shown that differences in bite force within caviomorphs could be better explained by changes in muscle development than in mechanical advantages (i.e., in cranial overall morphology). Considering the strong bites they apply, it is interesting to assess how the reaction forces upon the incisors (compression) and the powerful adductor musculature pulling (tension) mechanically affect the cranium, especially between species with different ecologies (e.g., chisel‐tooth digging). Thus, we ran finite element analyses upon crania of the subterranean Talas' tuco‐tuco Ctenomys talarum, the semi‐fossorial common degu Octodon degus, and the saxicolous long‐tailed chinchilla Chinchilla lanigera to simulate: (A) in vivo biting in all species, and (B) rescaled muscle forces in non‐ctenomyid rodents to match those of the tuco‐tuco. Results show that the stress patterns correlate with the mechanical demands of distinctive ecologies, on in vivo‐based simulations, with the subterranean tuco‐tuco being the most stressed species. In contrast, when standardizing all three species (rescaled models), non‐ctenomyid models exhibited a several‐fold increase in stress, in both magnitude and affected areas. Detailed observations evidenced that this increase in stress was higher in lateral sections of the snout and, mainly, the zygomatic arch; between approximately 2.5–3.5 times in the common degu and 4.0–5.0 times in the long‐tailed chinchilla. Yet, neither species, module, nor simulation condition presented load factor levels that would imply structural failure by strong, incidental biting. Our results let us conclude that caviomorphs have a high baseline for mechanical strength of the cranium because of the inheritance of a very robust "rodent" model, while interspecific differences are associated with particular masticatory habits and the concomitant level of development of the adductor musculature. Especially, the masseteric and zygomaticomandibular muscles contribute to >80% of the bite force, and therefore, their contraction is responsible for the highest strains upon their origin sites, that is, the zygomatic arch and the snout. Thus, the robust crania of the subterranean and highly aggressive tuco‐tucos allow them to withstand much stronger forces than degus or chinchillas, such as the ones produced by their hypertrophied jaw adductor muscles or imparted by the soil reaction. [ABSTRACT FROM AUTHOR]

Understanding the biting behaviour of vectors is essential for determining their vectorial potential and, hence, their role in disease transmission. The study was a two-year entomological survey of malaria vectors in three agrarian communities of Kano state designated as large irrigation (LIC), urban irrigation (UIC) and nonirrigation (NIC) communities. Human-baited Centre for Disease Control (CDC) light traps collected outdoor and indoor biting adult mosquitoes overnight. The collected female Anopheles species were morphologically identified to the species level using standard keys. A total of six hundred and thirty-seven (637) female Anopheles species were trapped of which 322 (50.55%) were collected indoors and 315 (49.45%) were collected outdoors. LIC and NIC had more Anopheles mosquitoes collected outdoors (51.08% and 66.04% respectively) than indoors (48.92% and 33.96% respectively) while UIC had more Anopheles mosquitoes collected indoors (67.77%) than outdoors (32,23%). Mosquito biting activity was higher in the wet season than in the dry season but did not differ significantly indoors (F-value = 3.310, p = 0.84) and outdoors (F = 0.651, p = 0.532). Statistical differences were recorded in the mean outdoor Anopheles abundance (F = 4.51 and p = 0.044) across the communities. Single, bimodal, and multiple biting peaks were observed in the study. Early biting peaks (1800-1900 hours) were observed outdoors (wet season) in NIC and indoors in UIC (dry season). The early outdoor biting activities of Anopheles species established in this study suggest the possibility of continued malarial transmission despite household use of bed nets. This implies that this control measure might be insufficient for malaria control in the region, and thus integrated methods for controlling malaria vectors should be considered. [ABSTRACT FROM AUTHOR]

Objectives: The multifactorial aspect of malocclusions and their consequences on ingestion function is rarely described in the literature. The aims of this review are (i) to investigate the relationship between oral ingestion and malocclusion and (ii) to gather malocclusion tools that could help screen subjects at risk of malocclusion-related ingestion disorders. Material and methods: A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol (PRISMA-P 2015) guidelines. The analysis methods and inclusion criteria have been documented in a protocol published in the Prospective International Register of Systematic Reviews (PROSPERO) under the registration number CRD42023395840. The bibliographic search involved the PubMed®, Cochrane and PROSPERO databases. Results: A total of 29 articles published between 2007 and 2023 were retained by the search criteria for the qualitative synthesis. Twenty of the studies found that the severity of malocclusion has a negative impact on oral ingestion. This review highlights that malocclusion and ingestion impairments are associated but it is not possible to determine causality due to the observational approach of many of the studies. Conclusion: Malocclusion has a negative impact on ingestion function. During orthodontic consultations, particular interest should be directed towards chewing, biting, and swallowing disorders, which can affect patients’ nutritional status. This review offers arguments for designing further studies assessing the extent to which malocclusions may affect nutritional status. Clinical relevance: Orthodontic treatment should focus on improving patients’ ingestion. [ABSTRACT FROM AUTHOR]

Financial feasibility analysis related to the formation of economic destinations is carried out to formulate the required information related to resources, costs, benefits, and feasibility by what is proposed and expected. This research was conducted to determine business estimation and planning for establishing economic destinations in Malang Regency. This study uses the mixed method, namely collecting information qualitatively related to the skewer-biting business unit and quantitatively calculating the skewer-biting business's feasibility in an estimated period of 20 years. This research was conducted purposively to biting business owners in Malang Regency. Data collection was carried out by observation, interviews, documentation, and feasibility calculations. Based on the results of the analysis, it was found that within 20 years, the formation of economic destinations can be formed with the value of each eligibility consisting of a positive NPV of IDR 988,153,018, BCR has a value of > 1 which is 2.04, IRR shows a value of 23% , and a payback period of 7 years during implementation.

Stimulants are the first-line pharmacological treatment for attention deficit hyperactivity disorder (ADHD). We present the unique case of a patient who developed a chewing compulsion when taking mixed amphetamine salts (MAS). A 32-year-old female patient with a past medical history of gastroesophageal reflux disease (GERD), gastroparesis, and migraines was seen for initial psychiatric assessment due to concerns for irritability. She was diagnosed with post-traumatic stress disorder (PTSD); generalized anxiety disorder; ADHD, inattentive type; and unspecified bipolar disorder. Lamotrigine was started and titrated to 25mg twice per day, with improved mood stability. MAS immediate-release (IR) was started at 2.5mg and titrated to 5mg daily for ADHD. She then experienced an uncontrollable urge to chew, finding relief when chewing on a child's teething necklace, which provided satisfaction and a reduction in anxiety. She denied jaw tightness or teeth grinding. The dose of MAS IR was reduced to 2.5mg daily with improvement in symptoms and later increased again to 5mg daily, which she was then able to tolerate. Stereotyped biting behaviors have been observed in rats with the use of amphetamines, and the onset of compulsive behavior has emerged in children with the use of dextroamphetamine. However, this is the first known case of compulsive chewing or biting movements reported in humans with MAS use. This case highlights the need to assess patients for adverse events, such as compulsive biting and chewing movements or other oral facial stereotypies, after commencement of stimulants, including MAS. [ABSTRACT FROM AUTHOR]

Occlusal disturbances affect human posture and sports performance. This study aimed to monitor biomechanical adaptations to personalized occlusal splints. Splints were customized based on stabilometry, thermography, sEMG, and kinesiography, and administered to three triathlon athletes. They were evaluated during a 4-month period, using isokinetic indexes, running kinematics and anaerobic outputs. Individuality emerged as a key factor driving type, quantity, quality, and time trajectories of adaptations. The use of instrumental and clinical tests allowed the detection of static balance and biting function improvements, but not necessarily parallel to sports performance improvements. The authors argue that strength and kinematic imbalances are joint and task-specific and support the use of multi-stage monitoring of the biomechanical effect of mouthpieces. Kinematics of cycling and running may be widely assessed with ecological and inexpensive methods. Strength imbalances need to be continuously monitored due to the high informative value to injury prevention. [ABSTRACT FROM AUTHOR]

Herbivorous fishes form a keystone component of reef ecosystems, yet the functional mechanisms underlying their feeding performance are poorly understood. In water, gravity is counter-balanced by buoyancy, hence fish are recoiled backwards after every bite they take from the substrate. To overcome this recoil and maintain contact with the algae covered substrate, fish need to generate thrust while feeding. However, the locomotory performance of reef herbivores in the context of feeding has hitherto been ignored. We used a three-dimensional high-speed video system to track mouth and body kinematics during in situ feeding strikes of fishes in the genus Zebrasoma, while synchronously recording the forces exerted on the substrate. These herbivores committed stereotypic and coordinated body and fin movements when feeding off the substrate and these movements determined algal biomass removed. Specifically, the speed of rapidly backing away from the substrate was associated with the magnitude of the pull force and the biomass of algae removed from the substrate per feeding bout. Our new framework for measuring biting performance in situ demonstrates that coordinated movements of the body and fins play a crucial role in herbivore foraging performance and may explain major axes of body and fin shape diversification across reef herbivore guilds.

Simple Summary: Mosquitoes are able to transmit a wide variety of devastating pathogens when they bite and obtain blood from their vertebrate hosts. Therefore, identifying the physiological processes required for biting by vector mosquitoes can contribute to developing strategies to suppress biting behavior and prevent disease transmission. In this study, we investigate the differential expression of small regulatory RNAs (microRNAs) between different strains of the Northern house mosquito, Culex pipiens, which is a major vector of West Nile virus and filarial nematodes. We measured differential microRNA expression specifically in the context of a behavioral biting assay, using populations with previously documented differences in biting propensity and the ability to produce eggs without a blood meal. We identified eight differentially expressed microRNAs; six of these are implicated in regulating physiological processes related to energy utilization, reproduction, and immunity. Our results are strikingly similar to previous studies demonstrating increased expression of messenger RNA-encoding proteins involved in energy utilization in association with biting. Furthermore, while previous studies have identified changes in microRNA expression occurring after consuming a blood meal, ours is the first study to demonstrate anticipatory changes in microRNA expression before blood is consumed. Understanding the molecular and physiological processes underlying biting behavior in vector mosquitoes has important implications for developing novel strategies to suppress disease transmission. Here, we conduct small-RNA sequencing and qRT-PCR to identify differentially expressed microRNAs (miRNAs) in the head tissues of two subspecies of Culex pipiens that differ in biting behavior and the ability to produce eggs without blood feeding. We identified eight differentially expressed miRNAs between biting C. pipiens pipiens (Pipiens) and non-biting C. pipiens molestus (Molestus); six of these miRNAs have validated functions or predicted targets related to energy utilization (miR8-5-p, miR-283, miR-2952-3p, miR-1891), reproduction (miR-1891), and immunity (miR-2934-3p, miR-92a, miR8-5-p). Although miRNAs regulating physiological processes associated with blood feeding have previously been shown to be differentially expressed in response to a blood meal, our results are the first to demonstrate differential miRNA expression in anticipation of a blood meal before blood is actually imbibed. We compare our current miRNA results to three previous studies of differential messenger RNA expression in the head tissues of mosquitoes. Taken together, the combined results consistently show that biting mosquitoes commit to specific physiological processes in anticipation of a blood meal, while non-biting mosquitoes mitigate these anticipatory costs. [ABSTRACT FROM AUTHOR]

To advance breeding techniques for the African freshwater pufferfish Tetraodon schoutedeni and observe tandem spawning closely, we monitored the reproduction of captive individuals. Eight spawning sessions (stable water temperature 24−25°C; daily light period 07:00−19:00) occurred between May 2016 and November 2017. After 65−150 min of tandem swimming (the male biting and clinging to the female's abdomen), 3−50 spherical, weakly adhesive eggs were spawned, being scattered onto the sandy substrate or water plants. The removal of cohabitants (potentially eating spawned eggs) and provision of small initial food items, such as small‐type Brachionus spp., for larval fish were essential for successful breeding. Research highlights: Freshwater pufferfish Tetraodon schoutedeni practiced tandem spawning. The larval fish were successfully reared utilizing small‐type Brachionus spp. as initial food. [ABSTRACT FROM AUTHOR]

The study was conducted to investigate the impact of various housing systems on the development of equine stereotypies. N=120 x Thoroughbred Pakistan of three different groups (A=40 horses 2years not gelded, B= 40 age 3 years and C= 40 four years gelded) were kept in four distinct types of housing systems, (SHSNI) Single Housing System No Interaction, (SHSLI) Single Housing System Limited Interaction, (DHS) Double Housing System and (GHS) Group Housing. The study was conducted in four phases (Phase-I SHSNI, Phase-II SHSNI, Phase-III DHS and Phase-IVGHS were used) and each phase was comprised of 30 days duration. On every 10th day parameters were recorded, and three readings were recorded in every housing system. A comprehensive set of 12 readings recorded through video recording, personal observation and information provided by horse handlers and randomized complete block design was performed for statistical analysis. Housing systems had significant (p<0.05) impact on the development of stereotypies. The highest incidence of stereotypies 35.83% was found in SHSNI, followed by 29.13% in DHS, 18.31% in GHS and the lowest 16.63% in SHSLI. The maximum number of horses displayed weaving (7.29%), behavior followed by kicking (6.45%), biting (6.03%) and crib-biting (5.83%). The groups (nongelding and gelding) were found non-significant (p>0.05). The study concludes that SHSLI is more suitable needed to be adopted, system has necessary social interaction, less stereotypies with limited injuries as compared to alternative housing systems. [ABSTRACT FROM AUTHOR]

Feeding kinematic studies inform our understanding of behavioral diversity and provide a framework for studying the flexibility and constraints of different prey acquisition strategies. However, little is known about the feeding behaviors used by many marine mammals. We characterized the feeding behaviors and associated kinematics of captive bearded (Erignathus barbatus), harbor (Phoca vitulina), ringed (Pusa hispida) and spotted (Phoca largha) seals through controlled feeding trials. All species primarily used a suction feeding strategy but were also observed using a biting strategy, specifically pierce feeding. Suction feeding was distinct from pierce feeding and was characterized by significantly faster feeding times, smaller gapes and gape angles, smaller gular depressions and fewer jaw motions. Most species showed higher variability in suction feeding performance than in pierce feeding, indicating that suction feeding is a behaviorally flexible strategy. Bearded seals were the only species for which there was strong correspondence between skull and dental morphology and feeding strategy, providing further support for their classification as suction feeding specialists. Harbor, ringed and spotted seals have been classified as pierce feeders based on skull and dental morphologies. Our behavioral and kinematic analyses show that suction feeding is also an important feeding strategy for these species, indicating that skull morphology alone does not capture the true diversity of feeding behaviors used by pinnipeds. The ability of all four species to use more than one feeding strategy is likely advantageous for foraging in spatially and temporally dynamic marine ecosystems that favor opportunistic predators.

Objective: This study investigated the early and late postoperative maximal bite force (MBF) values in pre-pubertal children undergoing adenotonsillectomy (AT) and compared them with healthy control. Methods: A total of children aged 6-12 years, diagnosed with chronic obstructive adenotonsillar hypertrophy (COATH), undergoing AT (n=30), and healthy controls (n=30) were included. The MBF and body mass index (BMI) were recorded for up to sixth months. The duration of active surgery was recorded. The visual analog scale (VAS) was applied to the patients for the pain on postoperative first and seventh days. Results: There was no significant difference in MBF values between the groups from the baseline to sixth month (p>0.05). A statistically strong positive correlation was observed between MBF and age (p<0.05). A significant difference was observed in MBF changes in patients with duratşon of active surgery more than 20 min compared with those with less from the baseline to the first month (p<0.05). In the study group, it was observed that there was a low and moderate correlation in the mean changes between the MBF and BMI in the first, 7th day, and 1st-month matches (p<0.05). The VAS scores did not show a significant correlation with the MBF values (p>0.05). Conclusion: The COATH and sex did not have a significant effect on MBF in pre-pubertal children, but age did. The postoperative MBF values were reached in the 1st month almost baseline values and there was a rapid increase between three and six months after AT. The prolonged operative time may affect MBF during one month postoperatively. [ABSTRACT FROM AUTHOR]

Recent biomechanical studies have focused on studying the response of teeth before and after different treatments under functional and parafunctional loads. These studies often involve experimental and/or finite element analysis (FEA). Current loading and boundary conditions may not entirely represent the real condition of the tooth in clinical situations. The importance of homogenizing both sample characterization and boundary conditions definition for future dental biomechanical studies is highlighted. The mechanical properties of dental structural tissues are presented, along with the effect of functional and parafunctional loads and other environmental and biological parameters that may influence tooth survival. A range of values for Young's modulus, Poisson ratio, compressive strength, threshold stress intensity factor and fracture toughness are provided for enamel and dentin; as well as Young's modulus and Poisson ratio for the PDL, trabecular and cortical bone. Angles, loading magnitude and frequency are provided for functional and parafunctional loads. The environmental and physiological conditions (age, gender, tooth, humidity, etc.), that may influence tooth survival are also discussed. Oversimplifications of biomechanical models could end up in results that divert from the natural behavior of teeth. Experimental validation models with close-to-reality boundary conditions should be developed to compare the validity of simplified models. [ABSTRACT FROM AUTHOR]

Abstract Microbiome research has gained considerable interest due to the emerging evidence of its impact on human and animal health. As in other animals, the gut-associated microbiota of mosquitoes affect host fitness and other phenotypes. It is now well established that microbes can alter pathogen transmission in mosquitoes, either positively or negatively, and avenues are being explored to exploit microbes for vector control. However, less attention has been paid to how microbiota affect phenotypes that impact vectorial capacity. Several mosquito and pathogen components, such as vector density, biting rate, survival, vector competence, and the pathogen extrinsic incubation period all influence pathogen transmission. Recent studies also indicate that mosquito gut-associated microbes can impact each of these components, and therefore ultimately modulate vectorial capacity. Promisingly, this expands the options available to exploit microbes for vector control by also targeting parameters that affect vectorial capacity. However, there are still many knowledge gaps regarding mosquito–microbe interactions that need to be addressed in order to exploit them efficiently. Here, we review current evidence of impacts of the microbiome on aspects of vectorial capacity, and we highlight likely opportunities for novel vector control strategies and areas where further studies are required. Video abstract

Functional analyses and treatments of self‐injurious behavior and aggression have shown that such behavior is often operant. In this paper, we will revisit evidence that a subset of self‐injurious and aggressive biting may be controlled primarily by antecedent events and may have phylogenetic origins. We propose that there is a research gap of more than four decades, if one considers the wealth of basic research on biting that occurred prior to 1977. To our knowledge, that body of basic research was never fully translated or directly applied within behavior analysis. It is known that organisms (including humans) sometimes bite in the presence of aversive events (broadly defined as the presentation of aversive stimuli or the removal of reinforcers). Thus, the variables controlling biting in the context of behavioral assessment and treatment require further analysis. [ABSTRACT FROM AUTHOR]

ObjectiveTo investigate the effects of oral-motor training with exergames on motor performance and motor skill acquisition in two different age groups.MethodsThirty-two healthy participants were recruited in the current pilot study and divided equally into two groups (Gen Z and Baby Boomers) according to their age. A pair of electromyographic (EMG) electrodes were placed on the participants’ masseter muscles. The EMG device communicated via Bluetooth with a mobile video game in response to the electromyographic activity of the masseter muscles during clenching. During the experimental session, participants were asked to play a video game in five blocks of 5 min each, with a 3-min break between each time block. The goal of the game was to collect as many coins (game points) as possible and to dodge/avoid upcoming obstacles (game life). Motor performance was assessed by performance scores and the number of game lives. Skill acquisition was measured by task efficiency (ratio of performance scores and number of game lives) across time blocks.ResultsThe results of the study showed significantly lower performance scores (p < 0.001), a higher number of game lives (p < 0.001), and lower task efficiency in the Baby Boomer group compared to the Gen Z group. Specifically, the results showed that there was a significant difference in task efficiency between the first and second, third and fourth, fourth- and fifth-time blocks in the Gen Z group (p < 0.002). However, there was only a significant difference between first- and second-time blocks in the Baby Boomer group (p = 1.012), suggesting that skill acquisition in the Baby Boomer group did not change significantly over the course of the time blocks.ConclusionThe study showed higher motor performance and superior motor skill acquisition with novel exergame training in the Gen Z group compared to the Baby Boomer group. The results of the study indicate that there is an improvement in oral motor skills with short-term training, yet the differences in oral motor skills between the two groups are still evident. The Baby Boomer group, unlike the Gen Z group, did not show robust improvement in task efficiency over the course of the series.

Objective: To investigate the effects of oral-motor training with exergames on motor performance and motor skill acquisition in two different age groups. Methods: Thirty-two healthy participants were recruited in the current pilot study and divided equally into two groups (Gen Z and Baby Boomers) according to their age. A pair of electromyographic (EMG) electrodes were placed on the participants' masseter muscles. The EMG device communicated via Bluetooth with a mobile video game in response to the electromyographic activity of the masseter muscles during clenching. During the experimental session, participants were asked to play a video game in five blocks of 5 min each, with a 3-min break between each time block. The goal of the game was to collect as many coins (game points) as possible and to dodge/avoid upcoming obstacles (game life). Motor performance was assessed by performance scores and the number of game lives. Skill acquisition was measured by task efficiency (ratio of performance scores and number of game lives) across time blocks. Results: The results of the study showed significantly lower performance scores (p < 0.001), a higher number of game lives (p < 0.001), and lower task efficiency in the Baby Boomer group compared to the Gen Z group. Specifically, the results showed that there was a significant difference in task efficiency between the first and second, third and fourth, fourth- and fifth-time blocks in the Gen Z group (p < 0.002). However, there was only a significant difference between first- and second-time blocks in the Baby Boomer group (p = 1.012), suggesting that skill acquisition in the Baby Boomer group did not change significantly over the course of the time blocks. Conclusion: The study showed higher motor performance and superior motor skill acquisition with novel exergame training in the Gen Z group compared to the Baby Boomer group. The results of the study indicate that there is an improvement in oral motor skills with short-term training, yet the differences in oral motor skills between the two groups are still evident. The Baby Boomer group, unlike the Gen Z group, did not show robust improvement in task efficiency over the course of the series. [ABSTRACT FROM AUTHOR]

Secondarily aquatic tetrapods have many unique morphologic adaptations for life underwater compared with their terrestrial counterparts. A key innovation during the land‐to‐water transition was feeding. Pinnipeds, a clade of air‐breathing marine carnivorans that include seals, sea lions, and walruses, have evolved multiple strategies for aquatic feeding (e.g., biting, suction feeding). Numerous studies have examined the pinniped skull and dental specializations for underwater feeding. However, data on the pinniped craniofacial musculoskeletal system and its role in aquatic feeding are rare. Therefore, the objectives of this study were to conduct a comparative analysis of pinniped craniofacial musculature and examine the function of the craniofacial musculature in facilitating different aquatic feeding strategies. We performed anatomic dissections of 35 specimens across six pinniped species. We describe 32 pinniped craniofacial muscles—including facial expression, mastication, tongue, hyoid, and soft palate muscles. Pinnipeds broadly conform to mammalian patterns of craniofacial muscle morphology. Pinnipeds also exhibit unique musculoskeletal morphologies—in muscle position, attachments, and size—that likely represent adaptations for different aquatic feeding strategies. Suction feeding specialists (bearded and northern elephant seals) have a significantly larger masseter than biters. Further, northern elephant seals have large and unique tongue and hyoid muscle morphologies compared with other pinniped species. These morphologic changes likely help generate and withstand suction pressures necessary for drawing water and prey into the mouth. In contrast, biting taxa (California sea lions, harbor, ringed, and Weddell seals) do not exhibit consistent craniofacial musculoskeletal adaptations that differentiate them from suction feeders. Generally, we discover that all pinnipeds have well‐developed and robust craniofacial musculature. Pinniped head musculature plays an important role in facilitating different aquatic feeding strategies. Together with behavioral and kinematic studies, our data suggest that pinnipeds' robust facial morphology allows animals to switch feeding strategies depending on the environmental context—a critical skill in a heterogeneous and rapidly changing underwater habitat. [ABSTRACT FROM AUTHOR]

Performance, the ability to complete an ecologically relevant task, serves as a link between underlying morphology and the maximum functional capacity and fitness of an individual. Performance can vary within species due to environmental context and the trait of interest, but this is less understood compared with variation across species. Trinidadian guppy (Poecilia reticulata) populations are separated by waterfall barriers that result in repeated selection for predator avoidance in high predation environments and resource competition in low predation environments. An array of locally adapted traits results from these shifts, however, the role of these local adaptations in prey capture performance traits remains unclear. We examined biting kinematics in replicate populations of adult female guppies collected from natural high and low predation habitats. We expected that competition in low predation populations would drive performance differences compared with fish from high predation populations. Using high‐speed videos of fish feeding on an agar substrate, we did not find support for differences in jaw or approach kinematics between populations, suggesting a lack of local adaptation in our sample. To gain further insight, we examined four representative, whole‐body morphometric traits previously shown to be divergent in guppies. Again, differences were not discovered in our sample, which may indicate limitations in the use of shape traits. We suggest that female guppies are kinematic generalists and that selection on prey capture may act on traits other than performance, such as feeding behaviors (e.g., consumption rates, kinematic integration, and prey preference). [ABSTRACT FROM AUTHOR]

It is critically important that early foal handling and training takes into account foals cognitive abilities and ability to cope with intense work without becoming overly aroused and fearful. Foals may experience days off during planned training programs due to owner/trainers circumstances and not as an intended part of the training schedule. Recent research has suggested that days off within training schedules may be beneficial to training outcomes. This study aimed to determine how the incorporation of days off during initial training influences foal learning outcomes. Twenty Thoroughbred foals underwent a 6-7 session training program. Foals were blocked by age (< or >8 weeks) and randomly allocated to either training condition A (trained for 2 consecutive days followed by a rest day, 2 more training days, rest day, finishing with up to 3 more consecutive training days) or training condition B (trained for 4 consecutive days, 2 rest days, finishing with up to 3 more consecutive training days). Qualified Foal NZ Ltd trainers used negative reinforcement to train foals to 'Go' (cranial pressure on the halter until foal steps forward) and 'Stop' (caudal pressure until the foal stops) from first, the left and second, the right side. Session length was determined by progress made and did not exceed 25 minutes. Training success was assessed by number of signals required (recall) for the foal to perform the task in the next training day. Biting behaviors exhibited by foals were instantaneously recorded during training sessions. Recall data for all tasks were non-parametric (left 'Go' Anderson Darling = 6.32; 'Stop' Anderson Darling = 2.89; right 'Go' Anderson Darling = 4.24; and 'Stop' Anderson Darling =6.10; all P < 0.005). Foals' recall of any of the tasks did not differ according to whether they were trained with 2 non-sequential days break (training condition A) or 2 consecutive days break (training condition B) for either younger or older foals (all Mann-Whitney U, P > 0.05). Younger foals (<8 weeks) trained using condition B showed significantly more biting (median = 7; range 0-9) in session 4 than those trained using condition A (median = 0; W = 36; P < 0.05); however, this difference disappeared by session 5 (median = 0; W = 46; P > 0.05). On the basis of the findings of this study, it is recommended that young foal initial training programs incorporate a day off within the first 4 days in order to decrease the development and occurrence of adverse behaviors such as biting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Central motor command regulates cardiovascular system during exercise. • Neuronal substrates involved in central command signaling are not fully understood. • Excited non-orexinergic neurons in the perifornical area evoked walking or biting. • This excitation simultaneously elicited pressor and tachycardiac responses in rats. • The neuronal population drives central command for walking or biting. Central command, a motor volition originating in the rostral part of the brain, plays a pivotal role in the precise regulation of autonomic nervous and cardiovascular systems. Central neuronal substrates responsible for transmitting central command signals remain incompletely understood. This study aimed to investigate the effect of optogenetic excitation of non-orexinergic (NOrx) neurons in the hypothalamic perifornical area (PeFA), where orexinergic neurons are densely distributed, on motor behaviors and cardiovascular parameters in rats. An adeno-associated viral serotype 2 vector carrying the human synapsin promoter encoding channelrhodopsin 2 (ChR2) fused to EYFP was injected into the PeFA of Sprague-Dawley rats, resulting in selective expression of ChR2-EYFP in NOrx PeFA neurons. In conscious rats, optogenetic excitation of NOrx PeFA neurons rapidly elicited walking or biting behavior, simultaneously causing pressor and tachycardiac responses regardless of the observed behavioral patterns. Under anesthesia, this excitation rapidly increased renal sympathetic nerve activity, immediately followed by sympathoinhibition. These findings suggest that NOrx PeFA neurons transmit central command signals, concurrently regulating somatomotor and autonomic nervous systems for locomotor exercise or biting behavior. [ABSTRACT FROM AUTHOR]

Microbiome research has gained considerable interest due to the emerging evidence of its impact on human and animal health. As in other animals, the gut-associated microbiota of mosquitoes affect host fitness and other phenotypes. It is now well established that microbes can alter pathogen transmission in mosquitoes, either positively or negatively, and avenues are being explored to exploit microbes for vector control. However, less attention has been paid to how microbiota affect phenotypes that impact vectorial capacity. Several mosquito and pathogen components, such as vector density, biting rate, survival, vector competence, and the pathogen extrinsic incubation period all influence pathogen transmission. Recent studies also indicate that mosquito gut-associated microbes can impact each of these components, and therefore ultimately modulate vectorial capacity. Promisingly, this expands the options available to exploit microbes for vector control by also targeting parameters that affect vectorial capacity. However, there are still many knowledge gaps regarding mosquito–microbe interactions that need to be addressed in order to exploit them efficiently. Here, we review current evidence of impacts of the microbiome on aspects of vectorial capacity, and we highlight likely opportunities for novel vector control strategies and areas where further studies are required. C7BhC7jCFhCSE5STu56Xta Video abstract [ABSTRACT FROM AUTHOR]

Endotracheal intubation, a procedure performed using an endotracheal tube (ETT), has been identified as one of the most viable and common methods of managing the airway and artificially supporting respiration. Patient consciousness is an essential factor that is directly linked to airway safety, and an acute drop in the level of consciousness might threaten the airway. A Glasgow Coma Scale score of less than 9/15 is an indication of the need to protect the airway by conducting the commonly known procedure of endotracheal intubation. In the current case report, we found an unusual cause of leakage in the ventilator tube that affected the tube integrity: the involuntary tube biting of a patient admitted to the intensive care unit due to low consciousness provoked by an ischemic stroke. This constitutes an interesting phenomenon that must be investigated further. Aside from deciphering the underlying subconscious event, mitigatory mechanisms should be deployed along with ETT to prevent the ventilator circuit from failing., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Ethics Committee at Jazan University issued approval 43/C/1773. The author affirms that the patient provided informed consent for the publication of the images in Figure 1. The patient has consented to the submission of the case report to the journal. The patient signed informed consent regarding publishing his data. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Ageel et al.)

Aims: To test the effects of occlusal force (OF) angle on the variations in predicted muscle and temporomandibular joint (TMJ) forces during unilateral molar bites. Methods: The craniomandibular (CM) geometries of 21 individuals were determined from lateral and posteroanterior cephalometric radiographs. These geometries were used in a numerical model based on minimization of muscle effort. This model was previously validated for this subject group through the use of jaw tracking and electromyographic data. The model predicted muscle and TMJ forces associated with static OFs on the right mandibular first molar. OF angle was varied from vertical to 40 degrees in the buccal and lingual directions, in increments of 10 degrees. Results: Intra- and intersubject variations in predicted muscle and TMJ forces for unilateral molar biting were dependent on OF angle and CM geometry. Nonvertical OFs were associated with either large anterior temporalis muscle forces (> 100% of applied OF in 3 subjects) or large inferior lateral pterygoid muscle forces (> 90% of applied OF in 3 subjects). On average, vertically and buccally directed OFs were associated with higher mean contralateral TMJ forces (60% of applied OF, SD 12%). Two subjects had large ipsilateral or contralateral TMJ forces (> 90% of applied OF). Conclusion: In a group of healthy subjects, depending on the individual CM geometry, large muscle and/or TMJ forces were predicted to be associated with specific unilateral molar OF angles. Propensities to increased muscle or joint forces may be predisposing factors in the development of myofascial pain or intracapsular disease. The results may explain, in part, the variation in location of symptoms in individuals who first present with temporomandibular disorders. [ABSTRACT FROM AUTHOR]

Abstract Background Host-seeking behaviours in anopheline mosquitoes are time-of-day specific, with a greater propensity for nocturnal biting. We investigated how a short exposure to light presented during the night or late day can inhibit biting activity and modulate flight activity behaviour. Results Anopheles gambiae (s.s.), maintained on a 12:12 LD cycle, were exposed transiently to white light for 10-min at the onset of night and the proportion taking a blood meal in a human biting assay was recorded every 2 h over an 8-h duration. The pulse significantly reduced biting propensity in mosquitoes 2 h following administration, in some trials for 4 h, and with no differences detected after 6 h. Conversely, biting levels were significantly elevated when mosquitoes were exposed to a dark treatment during the late day, suggesting that light suppresses biting behaviour even during the late daytime. These data reveal a potent effect of a discrete light pulse on biting behaviour that is both immediate and sustained. We expanded this approach to develop a method to reduce biting propensity throughout the night by exposing mosquitoes to a series of 6- or 10-min pulses presented every 2 h. We reveal both an immediate suppressive effect of light during the exposure period and 2 h after the pulse. This response was found to be effective during most times of the night: however, differential responses that were time-of-day specific suggest an underlying circadian property of the mosquito physiology that results in an altered treatment efficacy. Finally, we examined the immediate and sustained effects of light on mosquito flight activity behaviour following exposure to a 30-min pulse, and observed activity suppression during early night, and elevated activity during the late night. Conclusions As mosquitoes and malaria parasites are becoming increasingly resistant to insecticide and drug treatment respectively, there is a necessity for the development of innovative control strategies beyond insecticide-treated nets (ITNs) and residual spraying. These data reveal the potent inhibitory effects of light exposure and the utility of multiple photic pulses presented at intervals during the night/late daytime, may prove to be an effective tool that complements established control methods.

Predictive factors associated with a decline in swallowing function after 2 years were examined in 3409 Japanese older people aged ≥ 75 years who had undergone a dental checkup in Gifu Prefecture, Japan. Participants with normal swallowing function in a baseline survey in April 2018 were followed for 2 years. Swallowing function was assessed using a repetitive saliva swallowing test. In our study, 429 participants (13%) who were swallowing less than three times in 30 s based on a repetitive saliva swallowing test after 2 years were diagnosed as those with decline in swallowing function. Multivariate logistic regression analyses showed the decline in swallowing function after 2 years was associated with the male gender (odds ratio [ORs]: 0.772; 95% confidence interval [CIs]: 0.615-0.969), age ≥ 81 years (presence; ORs: 1.523; 95% CIs: 1.224-1.895), support/care-need certification (presence; ORs: 1.815; 95% CIs: 1.361-2.394), periodontal pocket depth (PPD) ≥ 4 mm (presence; ORs: 1.469; 95% CIs: 1.163-1.856), difficulty in biting hard food (yes; ORs: 1.439; 95% CIs: 1.145-1.808), choking on tea and water (yes; ORs: 2.543; 95% CIs: 2.025-3.193), and dry mouth (yes; ORs: 1.316; 95% CIs: 1.052-1.646) at baseline. Therefore, the dental checkup items associated with a decline in swallowing function after 2 years were a PPD ≥ 4 mm, difficulty in biting hard food, choking on tea and water, and dry mouth. PPD status and confirming to the self-administered questionnaire about biting, choking, and dry mouth may be useful in predicting future decline in swallowing function.

The mechanical forces experienced during movement and the time constants of muscle activation are important determinants of the durations of behaviours, which may both be affected by size-dependent scaling. The mechanics of slow movements in small animals are dominated by elastic forces and are thus quasistatic (i.e. always near mechanical equilibrium). Muscular forces producing movement and elastic forces resisting movement should scale identically (proportional to mass2/3), leaving the scaling of the time constant of muscle activation to play a critical role in determining behavioural duration. We tested this hypothesis by measuring the duration of feeding behaviours in the marine mollusc Aplysia californica whose body sizes spanned three orders of magnitude. The duration of muscle activation was determined by measuring the time it took for muscles to produce maximum force as A. californica attempted to feed on tethered inedible seaweed, which provided an in vivo approximation of an isometric contraction. The timing of muscle activation scaled with mass0.3. The total duration of biting behaviours scaled identically, with mass0.3, indicating a lack of additional mechanical effects. The duration of swallowing behaviour, however, exhibited a shallower scaling of mass0.17. We suggest that this was due to the allometric growth of the anterior retractor muscle during development, as measured by micro-computed tomography (micro-CT) scans of buccal masses. Consequently, larger A. californica did not need to activate their muscles as fully to produce equivalent forces. These results indicate that muscle activation may be an important determinant of the scaling of behavioural durations in quasistatic systems., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

The house mouse (Mus musculus domesticus), as a successful invasive species worldwide, has to forage a variety of resources. Subantarctic mice display among the most notable diet shift from the usual omnivorous–granivorous diet, relying on a larger proportion of terrestrial animal prey. In agreement, a recent study of their mandible morphology evidenced an evolution of their mandible shape to optimize incisor biting and hence seize preys. Here, the incisors themselves are the focus of a morphometric analysis combined with a 3D study of their internal structure, aiming at a comparison between subantarctic populations (Guillou island, Kerguelen archipelago) with a range of western European continental, commensal mice. The predatory foraging behavior of Guillou mice was indeed associated with a sharper bevel of the lower incisor, which appears as an efficient morphology for piercing prey. The incisor of these mice also displays a reduced pulp cavity, suggesting slower eruption counterbalancing a reduced abrasion on such soft food material. The dynamics of the ever‐growing incisor may thus allow adaptive incisor sculpting and participate to the success of mice in foraging diverse resources. [ABSTRACT FROM AUTHOR]

This study investigated the behavioural effects of providing different enrichment materials to suckling piglets from 7 days-old until weaning. One object was attached to the pen wall (WALL), and the other was suspended in the middle of the pen (MID). Control group had the hessian fabric in both locations, and the two diverse groups had hessian and bamboo stick in alternate locations (i.e., BMID-HWALL and HMID-BWALL). Piglets behaviour was recorded on D0 (object introduction), D1, D5, D8, D12, and D14; at weaning and 1, 3, 5 and 15 days after. Groups did not differ in approaching or interacting with objects on D0. MID objects attracted more attention than WALL objects (p < 0.01). Piglets interacted more with hessian than bamboo (p < 0.001). They performed more oral manipulation and shaking with hessian (p < 0.001), but more pushing of bamboo (p < 0.001). Interactions with objects increased with time (p < 0.001), especially with hessian (p < 0.01), while interest in bamboo remained unchanged. Control piglets performed more biting than piglets with diverse enrichment (pooled data), both pre- and post-weaning (p < 0.05). Therefore, providing different types of enrichment material can reduce biting behaviour pre- and post-weaning. Hessian was favoured, possibly because this was easier to bite and shake, which were the behaviours most often observed.

The Snake-eyed Skink's intra- and inter-specific interactions and their impacts on the individual (e.g. injuries) have received little attention so far. As part of copulation, male lizards bite the females; observations confirm an old report that bites occur in the fore side of the body, along with more recently published information about the back side. Additionally, out of 435 individuals observed in situ, 10 had missing extremities (toes, ankles, etc.); however, further studies should identify the causes of such injury, e.g. male-male combat, predators. For the first time, an adult male was observed biting a juvenile ex situ; the specific reasons, however, remain unknown. This report should generate further interest in ecological and behavioral studies, assessing the costs and benefits to potential territorial defense, intra-specific combat, and predator pressure and escape mechanisms. [ABSTRACT FROM AUTHOR]

A draft UK Parliamentary Bill sought to criminalize assaults on emergency workers through biting and spitting. This seemed to be based on a fear of bloodborne virus transmission. We undertook a literature search to clarify the risk of hepatitis infection from such exposures. We identified 245 possible papers and then reduced these to those relevant to HBV and HCV transmission through biting or spitting and the scientific plausibility. Nine papers were identified, reporting 16 possible cases of HBV (15 bites, 1 spitting) and 2 of HCV transmission (both bites). Only 3 HBV transmissions by bites and 1 by spitting and both HCV transmissions were felt to be plausible. Although both HBV DNA and HCV RNA can be found in the saliva of infected patients, it seems unlikely that there is enough to transmit infection unless there is blood contamination. In conclusion, the risk of acquiring HCV through spitting is negligible and is very low for HBV. The risk is also low for acquiring HBV and HCV through biting, especially if no blood is apparent in the saliva. [ABSTRACT FROM AUTHOR]

Mice from the Orkney archipelago exhibit an important diversity regarding molar shape. While on some islands mice display a usual dental pattern, teeth from other islands display additional cusplets and unusual phenotypes that may constitute case studies for evaluating the potential functional relevance of dental changes. We developed a multifaceted approach combining 2D and 3D geometric morphometrics, dental topography, dental wear, biomechanics, estimations of masticatory muscles force, and in vivo bite force on wild-derived lab descendants exemplifying the two extreme dental morphologies. The two strains differed in the geometry of the upper and lower tooth rows, and in the topography of the upper row only. Surprisingly, the most unusual tooth morphology appeared as the least complex because tooth simplification overwhelmed the signal provided by the occurrence of additional cusplets. No difference in bite force nor muscle force was evidenced, showing that the important change in dental morphology was accommodated without major changes in the rest of the masticatory apparatus. The evolution of unusual dental phenotypes was possibly fueled by drift and inbreeding in small and isolated populations on remote islands of the archipelago. No functional counter-selection impeded this diversification, since the unusual dental phenotypes did not disrupt occlusion and mastication. [ABSTRACT FROM AUTHOR]