Lower Posture Research Articles

Dogs jumping on household members before going for a walk

Dogs exhibit some behaviors that can be undesirable to their owners. Among the most common is jumping on people, which has been primarily studied in the context of owners returning home. However, other situations have received little attention. The present study examined dogs jumping on household members in the period of time closely before going for a walk. Sometime during their life, 73% of dogs jumped on household members prior to a walk. Dogs were more likely to jump on household members when they were walked less than once per day than more than once per day. No significant associations of dogs jumping on household members with dog’s sex, dog’s size, or living with other dogs were found. Most dogs quickly wagged their hindquarters and/or tails, held their ears back, and approached in a lowered posture before jumping on their owner. Dogs were more likely to lick their owner’s mouth when the owner was crouching than when standing upright. No significant associations of owner’s body position with dog approaching in a lowered posture, quickly wagging hindquarters, quickly wagging tail, jumping on the owner, eagerly running about, or holding ears back were found. In conclusion, the frequency of walking and the human body position were associated with dogs jumping on household members and licking their owner’s mouth, respectively, before going for a walk.

Biomechanical effects of typical lower limb movements of Chen-style Tai Chi on knee joint.

The load and stress distribution on cartilage and meniscus of the knee joint in typical lower limb movements of Chen-style Tai Chi (TC) and deep squat (DS) were analyzed using finite element (FE) analysis. The loadings for this analysis consisted of muscle forces and ground reaction force (GRF), which were calculated through the inverse dynamic approach based on kinematics and force plate measurements obtained from motion capture experiments. Thirteen experienced practitioners performed four typical TC movements, namely, single whip (SW), brush knee and twist step (BKTS), stretch down (SD), and part the wild horse's mane (PWHM), which exhibit lower posture and greater lower limb force compared to other TC styles. The results indicated that TC required greater lower limb muscle strength than DS, resulting in greater knee joint forces. The stress on the medial cartilage in SW and BKTS fell within a range conductive to maintaining the balance between anabolism and catabolism of cartilage matrix. This was due to the fact that SW and BKTS reduce the medial to total tibiofemoral contact force ratios through knee abduction, which may effectively alleviate mild medial knee osteoarthritis (KOA). However, the greater medial contact force ratios observed in SD and PWHM resulted in great contact stresses that may aggravate the pain of patients with KOA. To mitigate these effects, practitioners should consider elevating their postures appropriately to reduce knee flexion angles, especially during the single-leg support phase. This adjustment can decrease the required muscle strength, load and stress on the knee joint.

The influence of sub-technique and skiing velocity on air drag in skating style cross-country skiing

In cross-country skiing, velocities range from 2 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document} up to more than 20 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document} across undulating terrain, and aerodynamics can, therefore, make a large impact on performance. The aim of this study was to investigate the influence of skiing velocity on air drag for skating sub-techniques and downhill postures (tuck). Dynamic and static drag measurements for two athletes were performed in a wind tunnel in relevant velocity ranges for each sub-technique. The drag area decreased with velocity from 2 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document} to around 10–12 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document}, where it plateaued. No difference in air drag was found between the sub-techniques performed in upright postures (G2–G4) and thereby relatively similar frontal areas. In the G5 sub-technique performed without poling action in a lower posture, the reduced air drag was approximately 28% lower than for G2–G4 at similar velocities, and could even be reduced by an additional 21.7% by keeping the arms tucked in front of the body. In the downhill tucked postures, athletes could reduce air drag by 23% by keeping a low tuck, compared to a high tuck with straight legs. The sub-techniques were tested both dynamically and by averaging the static positions throughout the movements. The air drag was on average 6.1% lower for dynamic movements, indicating that dynamical movements like in cross-country skiing should be tested dynamically when evaluating air drag. Finally, the chosen cycle rate had minimal influence on air drag.

Postural Control and Adaptation Strategy of Young Adults on Unstable Surface.

Balance control is essential for postural adjustment in physical activities. This study investigates the behavior of human postural control and the coordination and adaptation strategy of hip, knee, and ankle when standing on an unstable surface. Twenty participants were recruited. Four different conditions were investigated: a quiet bipedal stance with eyes open and eyes closed, and standing on an unstable surface with eyes open and eyes closed. Other than the joint angle, the standard body sway measures, such as sway area and sway velocity, were computed. A nonlinear time series measure, that is,sample entropy, was used to determine the regularity of the time series and body adaptability to change and perturbation. The results show that the body sway increases as the difficulty increases. This study also confirms the coordination of the hip, knee, and ankle to maintain body balance on the unstable surface by decreasing the joint angle and adopting a lower posture. Even though the individual joint has lower sample entropy value and is deemed to be rigid and less adaptive to perturbation, the postural control exhibits higher sample entropy value, particularly in the anterior-posterior direction, and has the ability to stabilize the body by manipulating the joints simultaneously. These outcomes suggest that an unstable surface not only challenges the human postural control, but also reduces the hip, knee, and ankle adaptability to perturbation, thus making it a great tool to train body balance.

Flexibility in action: Development of locomotion under overhead barriers.

Behavioral flexibility-the ability to tailor motor actions to changing body-environment relations-is critical for functional movement. Navigating the everyday environment requires the ability to generate a wide repertoire of actions, select the appropriate action for the current situation, and implement it quickly and accurately. We used a new, adjustable barrier paradigm to assess flexibility of motor actions in 20 17-month-old (eight girls, 12 boys) and 14 13-month-old (seven girls, eight boys) walking infants and a comparative sample of 14 adults (eight women, six men). Most participants were White, non-Hispanic, and middle class. Participants navigated under barriers normalized to their standing height (overhead, eye, chest, hip, and knee heights). Decreases in barrier height required lower postures for passage. Every participant altered their initial walking posture according to barrier height for every trial, and all but two 13-month-olds found solutions for passage. Compared to infants, adults displayed a wider variety of strategies (squat-walking, half-kneeling, etc.), found more appropriate solutions based on barrier height (ducked at eye height and low crawled at knee height), and implemented their solutions more quickly (within 4 s) and accurately (without bumping their heads against the barrier). Infants frequently crawled even when the barrier height did not warrant a low posture, displayed multiple postural shifts prior to passage and thus took longer to go, and often bumped their heads. Infants' improvements were related to age and walking experience. Thus, development of flexibility likely involves the contributions of multiple domains-motor, perception, and cognition-that facilitate strategy selection and implementation. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The Risk of Physical Fatigue At Different Level of Posture and Repetition During Manual Handling Task in Aerospace Manufacturing Industry

This paper aims toinvestigatethe risk of physical fatigue at different levels of posture and repetition during manual handling task. Ten subjects with nohistoryof musculoskeletal disorders performed manual handling tasks at three levels of posture and two levels of repetition. The task completion time is recorded during the experimental task and the subjects rated their perceived discomfort level after the task completion. The results indicated that the lower posture of hand at higher repetition resulted in higher perceived discomfort level that leads to higher risk of physical fatigue. The higher repetition requires higher rest time for recovery and required lengthy completion time. The findings of this study served as a reference to the manufacturing industry in manual handling task design and planning to mitigate issues related to work-related physical fatigue at different levels of posture and repetition that could lead to the risk of work-related musculoskeletal disorders (WMSDs).

VDT 작업에서 두부전방자세 위험수준에 따른 목의 피로와 Flexion-Relaxation 변수에 관한 연구

Objective: The aim of this study is to quantify the neck fatigue of the office in Visual Display Terminal (VDT) work using the parameters of the flexion-relaxation phenomenon. Background: VDT work comprises a large proportion of the office worker tasks. Although VDT work requires relatively less loads, it can stress the neck and shoulders of the workers who work for a long period time with awkward sitting postures. In spite of that many office workers are suffering from neck and shoulder pains, the current solution for musculoskeletal disorders of office workers is only a management approach. Thus, it is important to precisely quantify the fatigue of VDT workers for reducing the prevalence of musculoskeletal disorders in office workers and for improving working environment. Method: For this experiment, 23 males were recruited to compare flexion-relaxation parameters such as Flexion-Relaxation Ratio (FRR) and On/Offset angle, and subjective discomfort (Borg CR-10 scale) before and after VDT task during 50 minutes. Participants were divided into two groups (forward head posture (FHP) high risk group and FHP low risk group) based on the pre-FHP test. Results: FRP parameters changed after VDT task. The FRR was significantly decreased and On/Offset angles showed an increasing trend after the task. CVA was slightly lower in FHP high risk group during 50 minute of VDT task. Using this result, it was found that high risk group of FHP was maintained at a lower posture for a long time. In addition, the subjective discomfort also increased after task. Conclusion: Based on these results, VDT work causes fatigue to the worker. And this fatigue can be quantified using FRP parameters. In addition, it was confirmed that FRR can be used as an index to confirm the abnormality of neck. Application: These results can be used to quantify the fatigue caused by VDT work in office workers, and to further validate the improvement of musculoskeletal disorders.

Behavioral responses of a coastal flatfish to predation-associated cues and elevated CO2

The direct and indirect effects of ocean acidification (OA) on marine ecosystems are a growing concern. Studies with marine fishes suggest that elevated CO2 may affect behavior by interfering with an important brain neurotransmitter. OA effects on fish behavior are comparatively understudied in temperate and boreal species. In laboratory experiments, we first characterized speckled sanddab (Citharichthys stigmaeus) behavioral responses to potential predation cues (predator odor, damaged skin cues from injured conspecifics, and sight of a predator) under ambient CO2 levels (~400 μatm). Sanddab reduced conspicuousness and foraging at the sight of a predator, but increased activity and conspicuousness when exposed to damaged skin cues. We then examined the effects of elevated CO2 levels (~900 μatm and ~1500 μatm) on posture, activity, and foraging of sanddab, and the behavioral responses to damaged skin cues. Sanddab behavior appeared generally resilient to the effects of elevated CO2 levels, but there were non-significant trends of fish from the medium CO2 treatment exhibiting lower posture and activity scores, and reduced feeding activity. The resiliency of speckled sanddab to OA conditions may be related to their distribution in a coastal upwelling region with seasonally elevated CO2 levels. Alternatively, prolonged acclimation to elevated CO2 may have mitigated the effects observed in other fishes following shorter-term exposures. Additional studies of ecologically relevant behaviors across diverse species assemblages are necessary to evaluate the impact of ocean acidification on marine food webs.

A method for body posture classification of three-dimensional body models in the sagittal plane

The main purpose of this research was to develop a method for the classification of body posture types, using a three-dimensional body scanner and data on anthropometric measurement. A sample of 102 male test subjects, aged from 20 to 30 years, and without structural deformities of the locomotor system, were scanned. Anthropometric body measurement was performed and 16 measurements were selected to calculate upper and lower body curve angles as a set of posture indicators. The number of maximally different groups of test subjects was determined using k-means cluster analysis and factor analysis of established posture indicators. The sampling into three upper and three lower posture types showed the largest statistically significant differentiation, comparing the results of variance analysis between and within the obtained groups, which confirmed three main components extracted by factor analysis. Discriminant analysis used in order to determine differences between posture types showed which indicators are the most important when classifying test subjects belonging to a particular upper or lower posture type. Classification functions were defined based on discrimination functions and their factor loadings, and used to calculate a matrix of correctly classified test subjects. The classification matrix showed very high prediction possibility of established posture indicators and the proposed method for body posture classification.

Secular trends of hospitalization and in-hospital mortality rates of Q-wave and Non-Q-wave myocardial infarction in US: 1990-2006

Objective: The association of socioeconomic status with health is well-established. Nevertheless, the underlying mechanisms linking socioeconomic status to adverse health outcomes have yet to be established. We hypothesized that poor posture- as a risk factor in general health- would be directly related to socioeconomic status and, as such, eventually influence health. Materials and Methods: With cross-sectional design, in representative clustered sample of 100 children aged 7-11, kyphosis, lordosis, head and shoulder posture were examined. Socioeconomic status data was collected from parents. Logistic regression models were used in analysis by SPSS version 18 (α=0.05). Results: Poor posture was seen in 68% of the children. Lower posture scores were recorded in children with poorer socioeconomic status (p<0.01; β=0.769). In logistic regression (p<0.05), only 3 out of 5 estimates (Household income: β=0.244; Mother’s education: β=0.449; Father’s education: β=0.279) were statistically significant, while there was no association between the social class of parents and children’s posture. Conclusion: The observed association of socioeconomic status with children’s posture is probably the consequence of the perception that people with higher socioeconomic status have better nutritional conditions, and are more likely to be engaged in regular physical activities. The positive influence of sports has been more frequently reported by higher educated parents, and they are more likely to encourage their children to participate in physical activities. Moreover, the better posture which has been observed in children with higher socioeconomic status, might be caused by more postural education they receive from their highly educated parents.

Secular trends of hospitalization and in-hospital mortality rates of Q-wave and Non-Q-wave myocardial infarction in US: 1990-2006

Objective: The association of socioeconomic status with health is well-established. Nevertheless, the underlying mechanisms linking socioeconomic status to adverse health outcomes have yet to be established. We hypothesized that poor posture- as a risk factor in general health- would be directly related to socioeconomic status and, as such, eventually influence health. Materials and Methods: With cross-sectional design, in representative clustered sample of 100 children aged 7-11, kyphosis, lordosis, head and shoulder posture were examined. Socioeconomic status data was collected from parents. Logistic regression models were used in analysis by SPSS version 18 (α=0.05). Results: Poor posture was seen in 68% of the children. Lower posture scores were recorded in children with poorer socioeconomic status (p<0.01; β=0.769). In logistic regression (p<0.05), only 3 out of 5 estimates (Household income: β=0.244; Mother’s education: β=0.449; Father’s education: β=0.279) were statistically significant, while there was no association between the social class of parents and children’s posture. Conclusion: The observed association of socioeconomic status with children’s posture is probably the consequence of the perception that people with higher socioeconomic status have better nutritional conditions, and are more likely to be engaged in regular physical activities. The positive influence of sports has been more frequently reported by higher educated parents, and they are more likely to encourage their children to participate in physical activities. Moreover, the better posture which has been observed in children with higher socioeconomic status, might be caused by more postural education they receive from their highly educated parents.

Cephalometric evaluation of tongue position and airway remodelling in children treated with swallowing occlusal contact intercept appliance (S.O.C.I.A.)

IntroductionFacial growth changes the position of the jaws (in particular vertical position of the maxilla and antero-posterior position of the mandible) and may, in turn, modify the position of the tongue and the hyoid bone, thus, generating modifications of the upper airway space. In the present paper, effects on upper airway space and tongue position of a new functional appliance, the swallowing occlusal contact intercept appliance (SOCIA) have been investigated. Materials and methodsRetrospective cephaolmetric study of twenty-four children (mean age 9.46±1.60) with hyperdivergent Class II malocclusion with mandibular retrusion and atypical deglutition, was performed on radiographs taken before and after 24 months treatment with “SOCIA” appliance. The variables considered in this study, and analysed by means of a Paired t-test with a 5% level of significance, included the distance between the base of epiglottis (EB) and the tip of the tongue (TT), the distance from the tongue dorsum to EB-TT (TGH), the distance between the posterior nasal spine PNS and EB (VAL), SPAS, MAS and IAS (i.e. superior, medium and inferior pharyngeal airspace width). ResultsOur findings showed a significant increase in tongue length (TT-EB) and tongue height (TGH); thus, confirming the reposition of the tongue from a lower posture to its physiological position onto the palatal spot. These modifications of the tongue posture had effects on the upper airway space. The most important modifications were observed in SPAS, with a significant 5.9mm increase. Some increase was found also for MAS (0.83mm) and IAS (1.1mm) but without statistical significance. A significant increase (7.75mm) was also found for VAL, probably as a result of the augmentation of posterior facial height. ConclusionsSOCIA appliance is capable to improve tongue position and the superior posterior airway space, and, consequently, to improve deglutition, phonation and respiratory function.

Characterization of a dopamine transporter polymorphism and behavior in Belgian Malinois

BackgroundThe Belgian Malinois dog breed (MAL) is frequently used in law enforcement and military environments. Owners have reported seizures and unpredictable behavioral changes including dogs’ eyes “glazing over,” dogs’ lack of response to environmental stimuli, and loss of behavioral inhibition including owner-directed biting behavior. Dogs with severe behavioral changes may be euthanized as they can represent a danger to humans and other dogs. In the dog, the dopamine transporter gene (DAT) contains a 38-base pair variable number tandem repeat (DAT-VNTR); alleles have either one or two copies of the 38-base pair sequence. The objective of this study was to assess frequency of DAT-VNTR alleles, and characterize the association between DAT-VNTR alleles and behavior in MAL and other breeds.ResultsIn an American sample of 280 dogs comprising 26 breeds, most breeds are predominantly homozygous for the DAT-VNTR two-tandem-repeat allele (2/2). The one-tandem-repeat allele is over-represented in American MAL (AM-MAL) (n = 144), both as heterozygotes (1/2) and homozygotes (1/1). All AM-MAL with reported seizures (n = 5) were 1/1 genotype. For AM-MAL with at least one “1” allele (1/1 or 1/2 genotype, n = 121), owners reported higher levels of attention, increased frequency of episodic aggression, and increased frequency of loss of responsiveness to environmental stimuli. In behavior observations, Belgian Military Working Dogs (MWD) with 1/1 or 1/2 genotypes displayed fewer distracted behaviors and more stress-related behaviors such as lower posture and increased yawning. Handlers’ treatment of MWD varied with DAT-VNTR genotype as did dogs’ responses to handlers’ behavior. For 1/1 or 1/2 genotype MWD, 1) lower posture after the first aversive stimulus given by handlers was associated with poorer obedience performance; 2) increased aversive stimuli during protection exercises were associated with decreased performance; 3) more aversive stimuli during obedience were associated with more aversive stimuli during protection; and 4) handlers used more aversive stimuli in protection compared with obedience exercises.ConclusionsThe single copy allele of DAT-VNTR is associated with owner-reported seizures, loss of responsiveness to environmental stimuli, episodic aggression, and hyper-vigilance in MAL. Behavioral changes are associated with differential treatment by handlers. Findings should be considered preliminary until replicated in a larger sample.

Prenatal Cocaine Exposure and Motor Performance at 4 Months.

The relation between prenatal cocaine exposure and quality of movement was studied at 4 mo using the Posture and Fine Motor Assessment of Infants (PFMAI-I). Posture and fine motor scores of 4-month-old infants exposed to cocaine in utero (n = 370) were compared with an unexposed group (n = 533) within the context of gestational age, medical and demographic characteristics, and level of prenatal substance exposure using the PFMAI-I. Infants prenatally exposed to cocaine had significantly lower posture scores than infants in the unexposed group. There was no main effect of cocaine exposure on fine motor scores; however, there were independent effects of gestational age at birth on both posture and fine motor scores at 4-mo corrected age. These findings demonstrate independent contributions of prenatal cocaine exposure and prematurity to risk of motor delay and support the validity of the PFMAI-I as a measure of motor competence in early infancy.

The smell of danger: chemical recognition of fish predators by the invasive crayfish Procambarus clarkii

Summary 1. Since avoiding predation can compromise animal fitness, prey are expected to respond to different predator species with an intensity appropriate to the level of risk. In fresh waters, the threat of predation is typically assessed by chemical cues, in particular by odours released by either injured/disturbed conspecifics (conspecific alarm odour) or predators (predator odours). Here, we used the most widely distributed crayfish in the world, the invasive North American Procambarus clarkii, to investigate the relative effectiveness of odours emitted by fish predators compared with conspecific alarm odour. We also tested whether P. clarkii is able to discriminate between fish predators of which it has ‘experience’ (either recent, via introduction to the same water body, or old, by sharing a native range), as well as between fish predators that pose low or high risk. 2. The study was carried out on introduced populations of P. clarkii from two sites, characterised by different fish assemblages: the Malewa River (a tributary of Lake Naivasha, Kenya) and Lake Trasimeno (Italy). Laboratory experiments consisted of three sequential phases (‘water’, ‘food’ and ‘smell’ phases) and five treatments. Treatments differed in the odour presented during the smell phase, i.e. no odour (plain water) and odours from either injured conspecifics or three fish species per site. Crayfish from the Malewa River population were confronted with the odours of largemouth bass (Micropterus salmoides), common carp (Cyprinus carpio) and tilapia (Tilapia zillii) (all introduced to Lake Naivasha but absent from the Malewa River), and those from the Lake Trasimeno population with the odours of the introduced largemouth bass and carp and the native chub (Squalius cephalus). Largemouth bass is the only predator that imposes a high risk to crayfish, and it also shares its native range with P. clarkii. We analysed the time spent by crayfish feeding, in locomotion and in adopting a raised or lowered posture. A reduction in the time spent feeding and in locomotion, and an increase in the time spent in the lowered posture were considered to indicate alarm. 3. Crayfish from both populations responded with a more pronounced reduction in feeding to conspecific alarm odour rather than to predator odours. Crayfish from the Malewa River reacted with the same intensity to the odours of the three fish species tested, whereas, in Lake Trasimeno, the odour of largemouth bass was significantly more threatening than the odours of the other two species. 4. Procambarus clarkii seems to perceive a general fish odour that alerts it to possible predation risk without the need of either a direct recent experience or via sharing a common native range. However, where they coexist with fish, crayfish become able to distinguish among species, adapting the intensity of their response to the effective risk. Our results confirm the relatively high learning capacity of P. clarkii reported in previous studies and suggest the existence of mechanisms that make predator recognition particularly efficient in this extraordinarily successful invader.

Responses to conspecific and heterospecific disturbance odours in the Australian crayfish Euastacus armatus and Cherax destructor

The responses of individuals of Cherax destructor and Euastacus armatus to water containing stressed or unstressed crayfish were tested in the laboratory. Individuals of E. armatus showed only an increase in locomotion when stressed crayfish water was introduced. Individuals of C. destructor showed a decrease in the time spent in a lowered posture, an increase in the time spent in the raised posture and in grooming behaviour when stressed crayfish water was introduced. Individuals of C. destructor responded more strongly to heterospecific animals (Cherax rotundus and E. armatus) than to conspecifics. The levels of responses to the two heterospecific species were similar.

Assessing undesired aggression in military working dogs

The present study assesses the reactions of military working dogs (MWDs) to potential aggression-inducing stimuli. A standardized aggression test was conducted on the dogs ( n = 31) and their behaviour was recorded on videotape and subsequently analyzed. The results of the test were compared with those from a questionnaire filled out by the handler prior to the test. Most dogs (83.87%) showed at least one act characteristic of aggressive behaviour during the test. In 69.35% of the cases, the dog's posture was lower than neutral. The results of this study showed that the dogs reacted to this test with fear-related aggression, as dogs exhibiting aggressive biting behaviour express a lower posture than dogs exhibiting either threatening or non-aggressive biting behaviour ( F 3488 = 10.71, p < 0.001). The results of the questionnaire showed that these patrol dogs have an important impact on the social and private life of the handlers. All dogs in this sample, which live at the handler's home, come into contact with family members including children, unknown persons and other dogs. Fearfulness has been cited as the most common reason for rejecting potential working dogs [Goddard, M.E., Beilharz, R.G., 1984. A factor analysis of fearfulness in potential guide dogs. Appl. Anim. Behav. Sci. 12, 253–265]. Therefore, in light of the important inter-specific interactions exhibited by these working dogs, measures are proposed to prevent and mitigate this undesirable temperamental trait. Further studies must be conducted to identify aggression-specific stimuli.

Training methods of military dog handlers and their effects on the team's performances

While only a few studies have analysed training methods used on working dogs, a recent survey in 303 Belgian military handlers revealed the use of harsh training methods on military working dogs (MWD). The present work aims at analysing the training methods used on Belgian MWD and the behaviour of handlers to objectify the performances of the dog handlers teams (DH teams) and the welfare of the animals. A standardized evaluation, including obedience and protection work exercises, was conducted on DH teams ( n = 33). Every evaluation was done twice to assess the reliability of the observation methods. The behaviours of MWD and handlers were recorded on videotape and subsequently analysed. Results showed that handlers rewarded or punished their dogs intermittently. Stroking and patting the dogs were the most frequently used rewards. Pulling on the leash and hanging dogs by their collars were the most commonly used aversive stimuli. The team's performance was influenced by the training method and by the dog's concentration: (1) low-performance dogs received more aversive stimuli than high-performance dogs; (2) dog's distraction influenced the performance: distracted dogs performed less well. Handlers punished more and rewarded less at the second evaluation than at the first one. This suggests that handlers modified their usual behaviour at the first evaluation in view to present themselves in a positive light. During the second evaluation the dogs reacted to this higher frequency of aversive stimuli as they exhibited a lower posture after aversive stimuli. The authors cannot prove that the welfare of these dogs had been hampered, but there is an indication that it was under threat. Low team performances suggest that DH teams should train more regularly and undertake the usefulness of setting a new training system that would rely on: the use of more positive training methods, an increased training frequency, the elaboration of a course on training principles, and an improvement of dog handler relationship.

SUCCESSFUL TREATMENT OF ATLANTOOCCIPITAL LUXATION IN AN ALPACA (LAMA PACOS)

A 7-mo-old male alpaca (Lama pacos) presented with an abnormal lowered posture of the head and neck and reluctance to walk. Cervical radiographs demonstrated atlantooccipital luxation. Successful manual closed reduction was achieved while the animal was anesthetized, resulting in complete return to normal gait and posture.

Responses of the Crayfish Orconectes Virilis to Chemical Cues Depend upon Flow Conditions

The responses of individuals of the crayfish Orconectes virilis to the same set of chemical cues were tested under flow (lotic) and non-flow (lentic) conditions. The cues presented to the crayfish were food cues, alarm |$\left( { = {\rm{ crushed \,\,conspecifics}}} \right)$| cues, and the combination of |${\rm{food \,\,+\,\, alarm}}$| cues. Crayfish behavior (time in burrows) and posture (lowered posture) were significantly affected by the odor treatment, the flow environment, and an interaction of treatment and environment. While the general patterns of responses to odors (more time spent feeding when food cues were introduced, and more time spent in lowered posture and in burrow when alarm cues were introduced) were qualitatively similar in the two environments, responses were stronger (especially to food odors) in the environment with flow. However, the different strength of these responses seemed not to be related to the directional information provided by the flow but rather was probably the effect of a difference in crayfish behavior between lentic and lotic environments in the control (no added chemical cues). In flow, crayfish spent less time executing feeding movements and more time in the lowered posture and in the burrow than in no-flow conditions.