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OBJECTIVE: To compare the thermal nociceptive thresholds (TNTs) of dogs from three working/sport breeds. STUDY DESIGN: Experimental prospective study. ANIMALS: Thirty healthy adult dogs of mixed age, sex and reproductive status, 10 of each of three breeds: Harrier Hound, Greyhound and New Zealand Huntaway. METHODS: On one day of each week for 4 weeks, unrestrained dogs were tested six times. TNTs were measured using a remotely activated device comprising a thermode attached to the thoracic limb, controlled by a microprocessor attached to the animal. Latency to exhibit behaviour indicative of nociception after initiation of heating and the temperature of the thermode at the point of behavioural response were measured. Linear mixed-effects models were fitted to the data, with dog included as a random effect, initial thermode temperature as a covariate and day, week and breed as fixed effects. RESULTS: Initial thermode temperature significantly affected dogs' latency to respond (p < 0.001). Breed had a significant effect on both latency to respond and response temperature. Huntaways took longer to respond than Harriers or Greyhounds. For example, when the initial thermode temperature was 30 °C, Huntaways took 39.0 seconds to respond compared with 35.8 seconds for Harriers and 36.8 seconds for Greyhounds. Huntaways also responded at higher temperatures (mean±standard deviation: Huntaways 49.7±1.3 °C, Harriers 48.4±1.6 °C and Greyhounds 48.7±1.6 °C). CONCLUSIONS AND CLINICAL RELEVANCE: Huntaways appeared to be less sensitive to thermal pain than the other breeds. Such information could be used by researchers and clinicians to better understand the generalizability of data gathered from a specific breed to the wider canine population or to tailor more effective pharmacological approaches to pain management in dogs.
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Cães/fisiologia , Limiar da Dor , Animais , Feminino , Temperatura Alta/efeitos adversos , Masculino , Nociceptividade , Estudos Prospectivos , Especificidade da EspécieRESUMO
OBJECTIVE: Triplet-born lambs are less likely to survive to weaning than twin-born or single-born lambs. Appropriate ewe-lamb bonding behaviours and lamb vigour behaviours are necessary for survival of lambs. The aim of this experiment was to determine whether maternal nutrition during late pregnancy influenced behaviour of the ewe and her lambs soon after birth, and to determine whether mid-pregnancy body condition score (BCS) influenced any behavioural response. METHODS: The experiments included ewes that were in BCS 2.0, 2.5, or 3.0 in mid-pregnancy and were fed either ad libitum or to pregnancy-maintenance requirements in late-pregnancy (day 115 until 136 in experiment one, and day 128 until 141 in experiment two). The time taken for lambs to stand, contact dam, suck from dam and follow dam was recorded three to 18 h after birth. The number of high- and low-pitched bleats emitted by the ewe and lambs was recorded, along with maternal behaviour score (MBS) of the ewe. Lambs in experiment two underwent a maternal-recognition test at 12 or 24 h. RESULTS: There were significant effects of feeding treatment on bleating behaviour of ewes and lambs, but these were inconsistent among BCS groups and between experiments. Lamb vigour behaviours were not affected by feeding treatment. In experiment one, there was no effect of feeding treatment or BCS on MBS, but in experiment two, ewes in BCS3 in mid-pregnancy had greater MBS than ewes in BCS2 in mid-pregnancy (MBS 3.1/5 vs MBS 2.1/5; p<0.05). CONCLUSION: Given there were no repeatable effects on behaviour of ewes and lambs, ad libitum feeding rather than feeding for pregnancy-maintenance requirements cannot be used to improve behaviours soon after birth of triplet-bearing ewes in BCS 2-3 and their lambs in extensive pastoral conditions.
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OBJECTIVE: To assess the potential of a thermal carbon dioxide (CO2) laser to explore antinociception in pain-free cats. STUDY DESIGN: Experimental, prospective, blinded, randomized study. ANIMALS: Sixty healthy adult female cats with a (mean±standard deviation) weight of 3.3±0.6 kg. METHODS: Cats were systematically allocated to one of six treatments: saline 0.2 mL per cat; morphine 0.5 mg kg(-1); buprenorphine 20 µg kg(-1); medetomidine 2 µg kg(-1); tramadol 2 mg kg(-1), and ketoprofen 2 mg kg(-1). Latency to respond to thermal stimulation was assessed at baseline and at intervals of 15-30, 30-45, 45-60, 60-75, 90-105 and 120-135 minutes. Thermal thresholds were assessed using time to respond behaviourally to stimulation with a 500 mW CO2 laser. Within-treatment differences in response latency were assessed using Friedman's test. Differences amongst treatments were assessed using independent Kruskal-Wallis tests. Where significant effects were identified, pairwise comparisons were conducted to elucidate the direction of the effect. RESULTS: Cats treated with morphine (χ2=12.90, df=6, p=0.045) and tramadol (χ2=20.28, df=6, p=0.002) showed significant increases in latency to respond. However, subsequent pairwise comparisons indicated that differences in latencies at specific time-points were significant (p<0.05) only for tramadol at 60-75 and 90-105 minutes after administration (21.9 and 43.6 seconds, respectively) in comparison with baseline (11.0 seconds). No significant pairwise comparisons were found within the morphine treatment. Injections of saline, ketoprofen, medetomidine or buprenorphine showed no significant effect on latency to respond. CONCLUSIONS AND CLINICAL RELEVANCE: The CO2 laser technique may have utility in the assessment of thermal nociceptive thresholds in pain-free cats after analgesic administration and may provide a simpler alternative to existing systems. Further exploration is required to examine its sensitivity and comparative utility.
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Analgésicos/farmacologia , Lasers de Gás , Limiar da Dor/efeitos dos fármacos , Analgésicos/administração & dosagem , Animais , Buprenorfina/administração & dosagem , Buprenorfina/farmacologia , Gatos , Feminino , Temperatura Alta/efeitos adversos , Injeções Intramusculares/veterinária , Cetoprofeno/administração & dosagem , Cetoprofeno/farmacologia , Medetomidina/administração & dosagem , Medetomidina/farmacologia , Morfina/administração & dosagem , Morfina/farmacologia , Tramadol/administração & dosagem , Tramadol/farmacologiaRESUMO
Recognition of injuries in racing animals is essential to identify potential risk factors so actions can be taken to reduce or mitigate the cause of the injury to safeguard the animal. Racing greyhounds are subject to musculoskeletal injuries associated with athletic pursuit, in particular soft-tissue injuries, lacerations, and fractures. The objective of this study was therefore to determine risk factors for soft-tissue injuries, lacerations and fractures occurring during racing, using a cohort of greyhounds racing in New Zealand between 10th September 2014 and 31st July 2020. Dog-level, race-level and track-level risk factors for each outcome were assessed using mixed-effects multivariable logistic regression including trainer as a random effect. Throughout the study period there were 218,700 race starts by 4,914 greyhounds, with a total of 4,385 injuries. Of these, 3,067 (69.94%) were classed as soft-tissue injuries, 641 (14.62%) were reported as lacerations, and 458 (10.44%) were fractures. Greyhounds with a low racing frequency (racing more than 7 days apart) had 1.33 [95% confidence interval (CI): 1.06-1.67] times the odds of fracture compared to those racing more frequently. Older greyhounds had a greater odds of fracture compared with younger greyhounds. Racing every 7 days had a lower odds of soft-tissue injury compared with racing more than once a week. Dogs over 39 months had 1.53 (95% CI: 1.35-1.73) times the odds of sustaining a soft-tissue injury compared to the younger dogs. Greyhounds originating from Australia had a higher odds of fracture and laceration compared with New Zealand dogs. Better performing dogs (higher class) had a greater odds of fracture and laceration whilst maiden dogs had a higher odds of soft-tissue injury. Greyhounds starting from the outside box had a higher odds of fracture. There was considerable variation in the odds of soft-tissue injury at different racetracks. In conclusion, although the incidence of soft-tissue injuries was higher than other injury types, the repercussion of such injuries was less than those for fractures. The results from this study will help to inform intervention strategies aimed at reducing the rate of injuries in racing greyhounds, enhancing racing safety and greyhound welfare.
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Understanding animals' aversion is important to improving their welfare. Aversion is often assessed using an approach-avoidance (AA) test in which animals have to forfeit a reward if they want to avoid an event or environment presented in the same place. However, sometimes the event/environment suspected to be aversive may physically impair the animal's ability to withdraw from that place (i.e. its ability to express aversion), leading to incorrect interpretations. Combining AA with a Conditioned-Stimulus that predicts the event/environment may overcome this problem by allowing animals to demonstrate aversion without exposure to the stimulus. We aimed to validate this paradigm for testing aversion in chickens. Seven Hyline-Brown chickens were trained to obtain a food reward from a coloured bowl located in the test chamber (TC) of a two-chambered box; the reward was presented in a green bowl with an inactivated air canister or a red bowl with the canister activated to deliver an air puff. Two 5-minute tests were conducted, one with each bowl colour and both with the canister inactivated. All chickens entered TC with the green bowl. With the red bowl, two chickens entered on their first attempt, one fully entered after a partial entry (3/7 fully entered), two made only partial entries and two made no attempts to enter. Chickens spent less time in the TC with the red bowl (median 31s, IQR 7-252) compared to the green bowl (293s, IQR 290-294; p = 0.008). The higher ratio of partial to full entries, failure to enter the TC and less time spent in TC reflected chickens' aversion to the air puff, signalled by the red bowl. The paradigm allowed chickens to demonstrate aversion without exposure to the aversive stimulus during testing.
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Aprendizagem da Esquiva , Comportamento Animal , Animais , Galinhas , Condicionamento Clássico , Condicionamento OperanteRESUMO
Changes to the amount and patterns of sleep stages could be a useful tool to assess the effects of stress or changes to the environment in animal welfare research. However, the gold standard method, polysomnography PSG, is difficult to use with large animals such as dairy cows. Heart rate (HR) and heart rate variability (HRV) can be used to predict sleep stages in humans and could be useful as an easier method to identify sleep stages in cows. We compared the mean HR and HRV and lying posture of dairy cows at pasture and when housed, with sleep stages identified through PSG. HR and HRV were higher when cows were moving their heads or when lying flat on their side. Overall, mean HR decreased with depth of sleep. There was more variability in time between successive heart beats during REM sleep, and more variability in time between heart beats when cows were awake and in REM sleep. These shifts in HR measures between sleep stages followed similar patterns despite differences in mean HR between the groups. Our results show that HR and HRV measures could be a promising alternative method to PSG for assessing sleep in dairy cows.
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The welfare and wastage of racing greyhounds is a topic of public concern. Little is published about the racing patterns of these dogs in New Zealand. The aim of this study is to describe the pattern of greyhound racing in New Zealand. Data on all race starts between 1 August 2011 and 25 March 2018 were supplied by Greyhound Racing New Zealand. A cohort was created containing dogs that had a racing career between 1 August 2013 and 31 July 2017. Data were collated within a customized Microsoft Access database from electronic records of all racing starts for every dog within the 2013-2016 racing seasons. For this cohort of racing dogs, there were 97,973 race starts across 22,277 races involving 2393 individual greyhounds. The median number of days between racing starts was 7 days (inter-quartile range (IQR): 4-10 days). The median career length was 424 days (IQR: 206-647 days) and the median number of racing starts throughout a racing career was 35 (IQR: 16-59 starts). Dogs of similar ability finished their career at a similar age.
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The aim of this study was to conduct a cross-sectional survey of racing greyhound trainers in New Zealand in order to provide an overview of their training practices. A survey regarding training practices was posted to all registered greyhound training license holders in New Zealand in August 2019. Data were collected from a convenience sample of 48 trainers (35.6%; n = 48/137) who completed the survey. Other than the differences in the number of greyhounds in race training, the training programmes described by public trainers and owner trainers were similar. Trainers reported that the primary reason for registering young dogs for racing and for qualifying for racing was the ability to meet time milestones. Young dogs had a median of six (interquartile range (IQR): 4-10) trials before they commenced their racing career. Trainers described training practices that aimed to prepare greyhounds for race-day. Regardless of whether the dogs raced once or twice a week, most training programmes demonstrated high specificity where training involved two periods of load cycles through high-intensity workload. Trainers racing their greyhounds once a week simulated the workload of trainers racing their greyhounds twice a week by introducing one high-intensity (speed) workout during the week. Training programmes were structured to condition the dogs to the physiological and metabolic requirements of sprint racing. This study highlights the importance of the need for an improved understanding of training and competition load in order to enable future research in the field of racing greyhounds.
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OBJECTIVES: To characterize changes in the cerebro-cortical response of lambs to rubber-ring castration during the first 6 weeks of postnatal life. ANIMALS: Coopworth-Texel cross ram lambs between 3 hours and 44 days of age. METHODS: The electroencephalogram (EEG) and heart rate responses to rubber ring castration were compared. Anaesthesia was induced via a face mask and maintained with halothane in oxygen (e'(Hal) = 1.2%). Once a stable plane of anaesthesia had been achieved, data collection of EEG and electrocardiogram (ECG) commenced, and the lambs were castrated 15 minutes later, using rubber rings. Heart rate was derived from the ECG and the median frequency (F(50)), spectral edge frequency (F(95)) and total power (p(tot)) were derived from the EEG. RESULTS: Castration-induced changes in F(50) increased from 2 +/- 1.8% in the youngest lambs to a maximum of 33 +/- 8.9% in the 36 +/- 0.5 day-old lambs. Changes in F(95) increased from -7 +/- 3% in the youngest lambs to a maximum of 16 +/- 11% in the 36 +/- 0.5 day-old lambs. Linear regression analysis in lambs up to 10 days of age demonstrated a change in the response with age that was significantly different from zero for F(50) (r(2) = 0.28, p = 0.007) and F(95) (r(2) = 0.38, p = 0.001), but not for p(tot) or heart rate. CONCLUSION: This study identified significant changes in the responsiveness of the lambs' cerebral cortex to the noxious stimulation of castration over the first 7-10 days of postnatal life. The results suggest that mechanisms that suppress responses of the fetus to noxious stimulation may still be active in the first few days after birth. CLINICAL RELEVANCE: This study documents changes in central nociceptive processing which may reflect the ability of neonatal animals to perceive pain.
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Envelhecimento/fisiologia , Anestésicos Inalatórios/farmacologia , Eletroencefalografia/efeitos dos fármacos , Halotano/farmacologia , Orquiectomia/veterinária , Ovinos/fisiologia , Anestesia por Inalação/veterinária , Animais , Masculino , Medição da Dor/veterináriaRESUMO
The assessment of hoof conformation is important due to its recognized relationship with the biomechanical functionality of the hoof. Hoof conformation can be assessed using objective measures or subjective scores. However, to date, there are limited data using either method in dairy goats. Therefore, the aims were to (1) develop a reliable method of assessing hoof conformation in dairy goats, and (2) compare two aspects of a subjective assessment against corresponding objective measures as a means of validation. A total of 1035 goats contributed photographs across 16 commercial dairy goat farms. Photographs were taken of the left front and left hind hoof in the lateral and dorsal aspect at five assessments across the goats' first two lactations. Hoof conformation was assessed using five subjective scores (toe length, heel shape, fetlock shape, claw splay, and claw shape) and two objective measures (toe length ratio and claw splay distance). Following the training of two observers, high levels of inter and intra-reliability were achieved for both the subjective scores (>0.8 weighted kappa) and objective measures (>0.8 Lin's concordance correlation coefficient). Two aspects of the subjectively assessed ordinal scores were compared with the objective measures with high levels of accuracy (>0.8). This suggests that the subjective scores may be a suitable alternative to more time-consuming objective measures when assessment is completed using photographs.
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This descriptive study explored how end-of-life management was taught to students in all eight Australasian veterinary schools. A questionnaire-style interview guide was used by a representative at each university to conduct structured interviews with educators in a snowball sampling approach. Four categories of animals were addressed: livestock, equine, companion and avian/wildlife. This article focuses on the first part of the questionnaire: teaching the technical aspects of euthanasia. Euthanasia techniques were taught at more universities in clinical years than preclinical years. Clinical teaching relied on opportunities presenting, for example, euthanasia consultations. Few universities gave students a chance to practise euthanasia during a consultation and those that did were all with livestock. Competency in euthanasia techniques is an important aspect of clinical practice and these findings can be used to inform curriculum reviews of veterinary training.
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Currículo , Educação em Veterinária/estatística & dados numéricos , Eutanásia , Assistência Terminal/métodos , Bem-Estar do Animal , Animais , Estudantes/estatística & dados numéricosRESUMO
The importance of animal welfare and ethics (AWE) within the veterinary education should reflect community concerns and expectations about AWE, and the professional demands of veterinary accreditation on the first day of practice (or 'Day One' competences). Currently, much interest and debate surrounds the treatment of production animals, particularly around live export. To explore the attitudes to AWE of veterinary students in Australia and New Zealand, a survey was undertaken to (i) understand what students consider important AWE topics for initial production animal competence; and (ii) ascertain how these priorities correlated with gender, area of intended practice and stage-of-study. The results from 575 veterinary students showed that all students ranked strategies to address painful husbandry procedures as the most important issues on their first day in production animal practice. Additionally, it was found that the importance students assigned to an understanding of humanâ»animal interactions declined as they progressed through the veterinary course. In contrast, the importance of an understanding of euthanasia issues for production animals increased for male students as they progressed through the course, and remained consistently high in females. Females also gave higher ranking to the importance of understanding production animal stress associated with transport, and ranked strategies to address painful husbandry procedures more important than did males. These findings should help the development of AWE teaching resources that address students' attitudes and competence and that can be delivered when students are most receptive.
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Direct eye contact may function as a warning cue during interspecific interactions, and human staring has been shown to influence the behavior of many species. The authors used an arena test to assess whether human staring altered the behavior of domestic sheep (Ovis aries) compared with no human eye contact. Sheep glanced at the staring human's face more often in the first 2 min of the test, indicating that they perceived a difference between the human stimuli. Staring also elicited more locomotor activity and urination than averted gaze. However, there were no differences in fear-related behaviors, suggesting that a staring human did not represent a greater immediate threat than a nonwatching human. These results imply that human staring is a warning cue for domestic sheep, but no more. Without further reinforcement, sheep quickly habituated to the warning cue.
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Comunicação Animal , Animais Domésticos , Nível de Alerta , Sinais (Psicologia) , Fixação Ocular , Ovinos/psicologia , Animais , Atenção , Medo , Feminino , Vínculo Humano-Animal , Humanos , Atividade Motora , Especificidade da EspécieRESUMO
For liver biopsy in cattle, it is routine practice to only provide local anesthesia (LA) to the skin and muscle layers, with visceral tissues remaining unanesthetized. Cattle being biopsied may therefore benefit from additional analgesia. This study aimed to determine if non-steroidal anti-inflammatory drugs would decrease post-biopsy pain in cattle. Twenty-four dairy cows were allocated into four treatment groups: biopsy under LA only; biopsy under LA with ketoprofen; biopsy under LA with meloxicam; and a sham-biopsied control group. Behavior was observed for 4h immediately following biopsy, and for 2h each day for the first three days after biopsy. No significant differences in behavior were found between any treatment groups on any day. This suggests that any post-biopsy pain present was not of enough significance to alter the cows' normal behavior patterns. Without identifying post-biopsy pain, it is not possible to determine what effect NSAID analgesia may have had on alleviating it.
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Anestésicos Locais/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Biópsia/veterinária , Cetoprofeno/administração & dosagem , Manejo da Dor/veterinária , Procaína/administração & dosagem , Tiazinas/administração & dosagem , Tiazóis/administração & dosagem , Animais , Bovinos , Feminino , Fígado/cirurgia , Meloxicam , Distribuição AleatóriaRESUMO
This paper comprises brief descriptions by faculty at 13 veterinary schools in Europe, North America, South America, and Australasia that summarize undergraduate training in animal welfare at the respective schools and how students are assessed.
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Bem-Estar do Animal , Currículo , Educação em Veterinária/organização & administração , Educação em Veterinária/normas , Estudantes de Medicina/psicologia , Animais , Comportamento Animal/fisiologia , Conhecimentos, Atitudes e Prática em Saúde , HumanosRESUMO
We examined the physical properties of digesta from the proximal (sacciform) and distal (tubiform) regions of the forestomach of tammar and parma wallabies maintained on a ryegrass sward. The digesta exhibited high viscosity, which, in conjunction with low flow rates calculated from published retention times of particulate marker in the stomach, results in a low potential for macrofluid mixing during onflow of food by displacement. The pseudoplastic nature of the viscosity profile and very low "flow behavior index" also indicate that macrofluid mixing around haustrae would be very localized. These findings indicate that the uniform mixing of whole digesta required for continuously stirred tank reactors (CSTRs) is unlikely. Voidage, the proportion of digesta not occupied by solid material, and "consistency index" were greater in the digesta from the proximal than in the distal regions of the forestomach. We conclude that the mixing conditions in wallaby stomachs are better described as a partially emptying batch reactor (PEBR) than a CSTR series and that lower permeabilities in conjunction with higher viscosities decrease axial mixing and thus increase efficiency in PEBRs.
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Fenômenos Fisiológicos do Sistema Digestório , Conteúdo Gastrointestinal/química , Marsupiais/fisiologia , Animais , Sistema Digestório/anatomia & histologia , Feminino , Masculino , Reologia , Especificidade da Espécie , Viscosidade , Água/análiseRESUMO
Pain elicits a range of physiological and behavioural responses. These are commonly used to assess the impact of pain-inducing stimuli on animals, to determine whether or not significant pain is experienced and to devise strategies for alleviating pain. This paper outlines a range of principles and caveats to guide the evaluation of physiological and behavioural responses to painful stimuli, so that they can be better used to minimise pain in the experimental context. Although this advice is based on studies of farm animals responding to painful husbandry practices, it is more generally applicable.
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Comportamento Animal , Medição da Dor , Criação de Animais Domésticos , Animais , Dor/complicações , Estresse FisiológicoRESUMO
Relationships between males defending the same harem are described as cooperative or competitive and explained by mutualism, reciprocal altruism, and reproductive concessions or limited control between unequal contestants. These alternate hypotheses can be tested by removing males from harems. Some feral horse (Equus caballus) harems are defended by more than one and up to five stallions. We temporarily removed the subordinate stallion from two of six multi-stallion bands (a harem and its stallions) for three weeks during the breeding season. We monitored harems for changes in composition, and measured and compared rates of (i) intra- and inter-band stallion aggression, (ii) stallion aggression towards mares, and (iii) stallion-mare proximity before subordinate stallion removal and after his return with rates during his absence. Harems were successfully defended during the subordinate's absence and stallion-mare aggression was substantially reduced. Dominant stallions did not require assistance in harem defence, and heightened harassment of mares is directly attributable to subordinate stallion's residence, not characteristics of the dominant stallion or mares. Cooperative hypotheses do not appear to explain multi-stallion bands but the experiments in this study should be replicated further. The limited control hypothesis (e.g., mate-parasitism) appears better supported but we outline its limitations too.
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Cavalos , Comportamento Sexual Animal , Comportamento Social , Análise de Variância , Animais , Feminino , Masculino , Estatísticas não ParamétricasRESUMO
We used high definition radial, strain rate and intensity spatiotemporal mapping to quantify contractile movements of the body and associated structures of the rabbit caecum when the terminal ileum was being perfused with saline at a constant rate. This perfusion caused gradual distension of the caecum as a result of relative restriction of outflow from the ampulla caecalis. The body of the caecum exhibited two patterns of motility that appeared autonomous, i.e. occurred independently of any contractile activity at the inlet or outlet. Firstly, the pattern that we termed ladder activity consisted of an orderly sequential contraction of bundles of axially oriented circular muscle between the spiral turns of longitudinal muscle and proceeded either from base to tip or from tip to base at a similar frequency and velocity. Secondly, less-localised, rapidly propagating synchronous contractions of both circular and longitudinal muscle, which were more common when the caecum was distended, that were termed mass peristalsis. Movements of the ileum and sacculus rotundus occurred at the same frequency and were broadly coordinated. Distension of the distal sacculus occurred synchronously with contraction of the ileum and did not propagate in an orderly manner across the structure, i.e. was instantaneous. This pattern was consistent with hydrostatic distension. Contractions propagated through the ampulla caecalis in either an orad or an aborad direction at a similar frequency to, and broadly correlated with, those in the ileum. The frequencies of distension of the sacculus and of contraction in the ileum and ampulla were momentarily augmented during mass peristalsis. The authors conclude that there was some coordination between the contractile activity of the terminal ileum and the caecal ampulla during periods of ongoing inflow from the ileum and between these structures and the caecum during mass peristalsis.