Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “DEFECATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,549 records · Page 86Linked to original sources
PubMed2004

Constipation and intestinal neuronal dysplasia type B: a clinical follow-up study.

OBJECTIVE: Intestinal neuronal dysplasia type B (IND B) is one of the gastrointestinal motility disorders with a defined malformation of the parasympathetic submucous and myenteric ganglia. The clinical presentation of IND B is variable, ranging from intestinal obstruction in the neonatal period to acute or chronic constipation in childhood. METHODS: Between 1993 and 1996, 105 patients (49 females and 56 males) were treated for constipation, and in all of them an IND type B was confirmed histopathologically. Twenty-two neonates, 42 infants to 6 months of age (38% of them were premature, and 5% had additional malformations), and 41 patients to the age of 4 years were included in this study. All 105 patients had been treated conservatively. Treatment consisted of diet in all patients, cisapride in 70% of them, laxatives in 52%, and repeated anal dilatations in 12% of the patients. The mean duration of their treatment lasted from 3 months to 10 months (mean, 6 months). RESULTS: The clinical follow-up 5 to 9 years later in 89 of the 108 (85%) patients showed daily defecation in 80% of them and every second day in 14% of them. Only 5 (6%) patients experience recurrent constipation, which responds well to diet and laxatives. CONCLUSIONS: In young patients, constipation related to IND B can be treated successfully by conservative treatment regimens, including diet, laxatives, and prokinetic drugs.

Age of Onset↗
PubMed2005

J-pouch ileoanal anastomosis in children and adolescents with ulcerative colitis: functional outcome, satisfaction and impact on social life.

OBJECTIVES: The aim of this study was to evaluate, over a 10-year period, severe surgical complications, functional outcome, patient satisfaction and impact on social life after colectomy and J-pouch ileoanal anastomosis for children and adolescents <18 years with ulcerative colitis. METHODS: Data were extracted retrospectively from medical records and obtained by mailed questionnaire. RESULTS: Thirty patients (18 girls) with a median age of 15 years (range, 7-17 years) were identified. Two patients (7%) had the J-pouch removed because of intractable diarrhea. Twenty-seven of 28 patients with preserved J-pouch answered the questionnaire. The median follow-up was 3.7 years (range, 0.3-9.2 years). Surgical complications included eight of 30 patients (27%) with small bowel obstruction, one of 30 (4%) with intra-abdominal abscess and two of 30 (7%) with perforation of the small intestine. The median number of daytime bowel movements was six (range, 3-10) and the median number of nighttime bowel movements was one (range, 0-2). Twelve patients (44%) were completely continent for stool and mucus, 12 patients (44%) leaked now and then and three (12%) leaked often or always. Antibiotic treatment for pouchitis was given in 13 patients (48%). Seventeen patients (63%) were completely satisfied with the operation, nine patients (33%) found the result fairly good and one patient (4%) was not satisfied. Twenty-six patients (96%) reported their health as completely or fairly good. CONCLUSIONS: The majority of patients with an intact J-pouch had an acceptable functional result with respect to defecation frequency, continence and number of pouchitis episodes. Most patients reported being satisfied with the procedure.

Adolescent↗
PubMed1993

Anorectal manometry: techniques and clinical applications.

Anorectal manometry has gained wide acceptance as a helpful method to objectively assess the apparatus of defecation provided by the anorectal sphincter. The standard manometric evaluation enables measurement of resting and squeeze pressures, as well as of the length of the functional anal canal (high pressure zone [HPZ]). More detailed assessment of radial and longitudinal pressure profiles can also be generated from vector volume and vector symmetry index assessment. Adjuvant techniques using an intrarectal balloon allow assessment of the rectoanal inhibitory reflex (RAIR), rectal sensitivity, capacity, and compliance. Although anorectal manometry can be used as a diagnostic test in diseases such as Hirschsprung's disease, more often it is used to assess common disorders such as chronic idiopathic constipation and fecal incontinence. Anorectal manometry has also been considered as a preoperative evaluation in patients having abdominal and anorectal procedures during which the state of continence can be jeopardized.

Anal Canal↗
PubMed1997

The intestinal effects of bran-like plastic particles: is the concept of 'roughage' valid after all?

OBJECTIVE: The mechanisms by which dietary fibre exerts is laxative action are not fully understood. Studies using sliced plastic tubing as a fibre substitute showed a decrease in both small and large bowel transit time. The significance of these studies is hard to interpret. We set out to compare the effects on intestinal function of wheat bran with plastic flakes similar in size and flaky shape to wheat bran (and devoid of plasticizers). DESIGN AND METHODS: Volunteers consumed coarse wheat bran then, after a washout period, plastic flakes of the same size and shape as the bran. Before and after each intervention whole-gut transit time (WGTT), defecation frequency, stool form, stool water content, stool beta-glucuronidase activity and dietary intake were assessed. RESULTS: Twenty-nine volunteers consumed a mean of 27.1 g of raw wheat bran and 24 g of plastic flakes a day. Baseline WGTT, interdefecatory intervals (IDI), stool form, weight, output, water content, and beta-glucuronidase were similar before both interventions. Both led to a decrease in mean faecal beta-glucuronidase activity, median WGTT (bran 25.8%, plastic 28.6%) and IDI (bran 23.3% plastic 25.0%). Both also increased stool form score (bran 28.6%, plastic 21.2%) and stool output (bran 67.1%, plastic 79.0%). Stool water content only rose with wheat bran (72%-75%, P = 0.014). CONCLUSION: Overall, plastic 'pseudobran' was as effective at altering colonic function as wheat bran at a similar dosage but with fewer particles. The mechanism is not by increased faecal water. Reduction in enzyme activity with plastic flakes suggests that the plastic led to qualitative and, probably, beneficial changes in the bacterial flora or their metabolic processes. The concept of roughage deserves to be revived.

Adult↗
PubMed2001

Rectal inhibition by inferior rectal nerve stimulation in dogs: recognition of a new reflex--the 'voluntary anorectal inhibition reflex'.

OBJECTIVE: The effect of inferior rectal nerve (IRN) stimulation on the rectum was studied, postulating that nerve stimulation might inhibit rectal contractility and could thus be used in the management of defecation disorders. METHOD: The IRN was exposed through a para-anal incision in 12 dogs (18.2 +/- 3.3 SD kg, seven male, five female) and a cuff-type electrode was applied to the nerve. A balloon introduced into the rectum was filled with saline in increments of 5 ml. The rectal and rectal neck (anal canal) pressures, and the electromyographic (EMG) activity of the external anal sphincter (EAS) and Internal anal sphincter (IAS) were recorded until the balloon was expelled to the exterior. The test was repeated until the expulsion volume was reached, and the IRN was stimulated (pulse width 200 mu/s, charge density 2 to 6 microCi/cm2 per phase). The test was performed again following individual anaesthetization of the EAS and the IAS. RESULTS: At a mean rectal distending volume of 38.3 +/- 2.3 ml, the rectal pressure increased (P < 0.01), rectal neck pressure declined (P < 0.01), the EAS and IAS EMGs disappeared, and the balloon was expelled. IRN stimulation at a distending volume of 38.3 +/- 2.3 ml increased the EMG activity of the EAS, whereas the rectal pressure and IAS EMG did not change (P > 0.05) and the balloon was not expelled. With IRN stimulation at the distending volume of 38.3 +/- 2.3 ml while the EAS was anaesthetized, the rectal pressure increased (P < 0.01), rectal neck pressure diminished, IAS EMG activity disappeared, and the balloon was expelled. Upon repetition of IRN stimulation during anaesthetization of the IAS, the rectal pressure remained high and the balloon was not expelled. CONCLUSION: It is suggested that the EAS produces continence by a twofold action. The EAS prevents IAS relaxation on rectal contraction, with a resulting rectal relaxation. A reflex relationship is postulated to exist between failure of the IAS to relax and rectal relaxation. We call this reflex relationship 'voluntary anorectal inhibition reflex'. Secondly, the EAS mechanically compresses the rectal neck. It seems that contraction of the EAS, which is a striated muscle, mechanically occludes the rectal neck for a few seconds--enough for the rectum to relax in a reflex manner as an effect of the voluntary anorectal inhibition reflex.

Animals↗
PubMed2006

Update of tests of colon and rectal structure and function.

This review deals with the indications, methods, strengths, and limitations of anorectal testing in clinical practice. In chronic constipation, anal manometry and a rectal balloon expulsion test, occasionally supplemented by defecography, are useful to identify a functional defecatory disorder, because symptoms may respond to pelvic floor retraining. In patients with fecal incontinence, diagnostic testing complements the clinical assessment for evaluating the pathophysiology and guiding management. Manometry measures anal resting and squeeze pressures, which predominantly reflect internal and external anal sphincter function, respectively. Defecation may be indirectly assessed by measuring the recto-anal pressure gradient during straining and by the rectal balloon expulsion test. Endoanal ultrasound and magnetic resonance imaging (MRI) can identify anal sphincter structural pathology, which may be clinically occult, and/or amenable to surgical repair. Only MRI can identify external sphincter atrophy, whereas ultrasound is more sensitive for internal sphincter imaging. By characterizing rectal evacuation and puborectalis contraction, barium defecography may demonstrate an evacuation disorder, excessive perineal descent or a rectocele. Dynamic MRI can provide similar information and also image the bladder and genital organs without radiation exposure. Because the measurement of pudendal nerve latencies suffers from several limitations, anal sphincter electromyography is recommended when neurogenic sphincter weakness is suspected.

Anal Canal↗
PubMed2005

The prevalence of encopresis in a multicultural population.

BACKGROUND: Population-based studies on the prevalence of encopresis in children are scarce and generally outdated. Prevalence estimates based on clinical studies are unreliable because parents tend to be reticent to seek medical help for this problem. Professional help is necessary, however, because encopresis can lead to serious psychosocial health problems. The authors examined the prevalence of encopresis in children, the frequency of visits made to general practitioners for encopresis and the psychosocial health problems of encopretic children. METHODS: This population-based study involved 13,111 parents and their 5- to 6-year-old children and 9,780 parents and their 11- to 12-year-old children, all residents of Amsterdam, the Netherlands. RESULTS: The prevalence of encopresis was 4.1% in the 5-to-6 age group and 1.6% in the 11-to-12 age group. Encopresis was more frequent among boys and children from the very depressed areas of the city. Encopresis was less frequent among Moroccan and Turkish children. A defecation frequency of less than three per week was found in 3.8% of the 5- to 6-year-olds and 10.1% of the 11- to 12-year-olds with encopresis. Only 37.7% of the 5- to 6-year-olds and 27.4% of the 11- to 12-year-olds who had encopresis had ever been taken to see a doctor for this problem. Psychosocial problems were far more common among children with encopresis than among normal children. CONCLUSIONS: Encopresis is a common condition that is often associated with psychosocial health disorders but only a small proportion of the children with encopresis are taken to a general practitioner to discuss their problem.

Child↗
PubMed2006

The effect of abdominal massage on bowel function in patients with spinal cord injury.

OBJECTIVES: To investigate the effect of abdominal massage on clinical aspects of bowel dysfunction and colonic transit time in patients with spinal cord injury. Twenty-four patients were placed on a standard bowel program (phase I), after which abdominal massage was added to the regimen (phase II). Parameters of gastrointestinal system function and colonic transit times were evaluated. DESIGN: Uncontrolled clinical study. RESULTS: Eleven (45.8%) of the 24 patients had abdominal distention, and 10 (41.7%) had fecal incontinence in phase I; corresponding results for phase II were three (12.5%) and four (16.7%) (P = 0.008 and 0.031, respectively). There were no significant differences between the proportions of patients with difficult intestinal evacuation or abdominal pain or in mean time required for bowel evacuation in phase I vs. phase II. The mean frequencies of defecation in phases I and II were 3.79 +/- 2.15 (2.75-4.55) and 4.61 +/- 2.17 (3.67-5.54) bowel movements per week, respectively (P = 0.006). Mean total colonic transit time decreased from 90.60 +/- 32.67 (75.87-110.47) hrs in phase I to 72 +/- 34.10 (58.49-94.40) hrs in phase II (P = 0.035). CONCLUSIONS: Abdominal massage has positive effects on some clinical aspects of neurogenic bowel dysfunction in patients with spinal cord injury.

Abdomen↗
PubMed2004

Early outcomes of laparoscopic procedures performed on military personnel with total rectal prolapse and follow-up.

Total rectal prolapse is a disorder frequently associated with constipation and anal incontinence. The aim of this study was to evaluate the outcomes of the complications, pain management, hospital stay, constipation, and anal functions of the patients undergoing 2 types of laparoscopic surgical approaches. In this study, 33 patients underwent either laparoscopic rectopexy or hand-assisted laparoscopic resection rectopexy. Preoperative colonic transit time, defecation, postoperative pain scoring, pre-postoperative evaluation of the anal function, and the changes in constipation and relating symptoms were assessed. Postoperative evaluation had been performed at the sixth week and the twelfth month. Median operation time was 137 minutes for rectopexy and 230 minutes for resection rectopexy group. Median postoperative hospital stay was 3 days for patients with rectopexy and 7 days for patients with resection rectopexy. Patients needed painkillers in short postoperative period for pain management in both groups. Continence was improved in 11 of 13 patients (84.6%) in a year after laparoscopic surgery. In 15 patients (45.5%), preoperative constipation either remained in the same or became worse in 7 (21.1%) in a year after surgery. No patient developed recurrence in the median follow-up period, which was about 15 months. Laparoscopic rectopexy and resection rectopexy in the young aged patients working the Army are carried out with less morbidity rate. We eliminated the total prolapse and cure incontinence in almost all patients. In addition to constipation was reduced by laparoscopic surgical approaches in a short time hospitalization with short time painkiller need.

Adult↗
PubMedDate not supplied

Body temperature as a conditional response measure for pavlovian fear conditioning.

On six days rats were exposed to each of two contexts. They received an electric shock in one context and nothing in the other. Rats were tested later in each environment without shock. The rats froze and defecated more often in the shock-paired environment; they also exhibited a significantly larger elevation in rectal temperature in that environment. The rats discriminated between each context, and we suggest that the elevation in temperature is the consequence of associative learning. Thus, body temperature can be used as a conditional response measure in Pavlovian fear conditioning experiments that use footshock as the unconditional stimulus.

Animals↗
PubMed1995

The effect of oral vancomycin on chronic idiopathic constipation.

BACKGROUND: A case study reporting the efficacy of oral vancomycin in a patient with chronic idiopathic constipation prompted this prospective trial of oral vancomycin in eight female patients (aged 21-61 years) with severe constipation resistant to the action of dietary fibre. METHODS: The trial was divided into two consecutive 14-day periods. During the first period, each patient was given ispaghula, 3.5 g twice a day, and during the subsequent period they took 250 mg vancomycin t.d.s. per os, as well as the fibre supplement. During both periods they collected stools and recorded daily bowel symptoms (stool frequency, straining, stool consistency, subjective stool volume) in a diary. At the end of each period whole gut transit time and the breath hydrogen response to a standard meal, giving oro-caecal transit time, were measured along with gastrointestinal symptoms which were assessed on visual analogue scales. RESULTS: Vancomycin caused a significant improvement in stool frequency, consistency, ease of defecation and the amount of stool patients felt they produced (all P < 0.05), but objective measures of daily stool weight and whole gut or oro-caecal transit time were not significantly different. Basal breath hydrogen levels were higher after vancomycin treatment in seven out of eight patients. One patient experienced a complete remission of symptoms when she took vancomycin and remains in remission after 14 months. This patient showed no elevation in basal breath hydrogen level. CONCLUSION: Although this study does not support the use of vancomycin for most patients with constipation, the results suggest that modification of the intraluminal flora may be of value in the treatment of the occasional case of idiopathic constipation.

Administration, Oral↗
PubMed1985

The effects of dietary fibre in a liquid diet on bowel function of mentally retarded individuals.

A soy polysaccharide at a level of 20-22.3 g/day was added to a liquid formula diet provided to constipated, tube-fed, nonambulant, severely or profoundly mentally retarded individuals. This amount of polysaccharide contained 15.6-17.4 g of dietary fibre or 4.9-5.5 g of neutral detergent fibre. The fibre formula was well tolerated by the subjects and increased stool size and improved stool consistency. At these levels of fibre and short duration of the study, defecation rate and need for elimination aids were unaffected. Transit times of 5 to 6 days were unchanged but mean daily stool weights increased to a level equivalent to low normal values for healthy adults on a low fibre intake.

Adolescent↗
PubMed2006

Removal of tonic nitrergic inhibition is a potent stimulus for human proximal colonic propagating sequences.

Propagating sequences (PS) are important in colonic propulsion and defecation, yet the triggers of these motor patterns are not understood. Nonadrenergic noncholinergic neurones are believed to modulate smooth muscle in the gastrointestinal tract via the ubiquitous inhibitory neurotransmitter nitric oxide (NO). In the mouse colon periods of quiescence correlate with an increase in the release of NO. We investigated the colonic response to NO synthase inhibition in the conscious human subject. Intravenous infusion of saline or N(G)-monomethyl-L-arginine (L-NMMA; 3 or 6 mg kg(-1) h(-1)) occurred in random order in six healthy volunteers in whom a 5 m long nasocolonic manometry catheter was positioned such that 16 recording sites, at 7.5-cm intervals, spanned the terminal ileum and colon. L-NMMA infusion at 3 mg kg(-1) h(-1), but not 6 mg kg(-1) h(-1) significantly (P = 0.02) increased proximal colonic PS frequency (2.0 +/- 1.9 vs 11.7 +/- 7.0 PS h(-1)) and non-propagating motor activity (5,296 +/- 2,750 vs 6,362 +/- 1,275 mmHg s). We conclude that blockade of NO synthesis has a stimulatory effect on the frequency of proximal colonic PS. This suggests removal of tonic nitrergic inhibition of the colon might be a physiological stimulus for propagating activity.

Adult↗
PubMed2004

Visceral perception thresholds after rectal thermal and pressure stimuli in irritable bowel syndrome patients.

BACKGROUND AND AIM: Visceral hypersensitivity has been shown to be present in irritable bowel syndrome (IBS). The current study sought to compare the characteristics of visceral perception thresholds after rectal thermal and pressure stimuli between IBS patients and healthy subjects. METHODS: A total of 46 patients with IBS were diagnosed using Rome II criteria. Thirteen healthy individuals participated in the study. Rectal visceral perception thresholds were examined in patients with IBS and in normal controls after thermal and pressure stimuli. Subjects were asked to report the sensation type, location, and spread. RESULTS: Compared with healthy subjects, IBS patients demonstrated significantly initially lower perception thresholds and defecation thresholds to rectal thermal and pressure stimuli, particularly in patients with diarrhea-predominant IBS. Ice stimuli on the abdominal wall had varied effects on symptoms in patients with IBS and did not affect perception thresholds. CONCLUSIONS: Visceral perception thresholds were decreased significantly after rectal thermal and pressure stimuli in patients with IBS. Visceral hypersensitivity may be one of the important pathogenic mechanisms in IBS.

Adult↗
PubMed2004

Study of visceral hypersensitivity in irritable bowel syndrome.

OBJECTIVE: Visceral hypersensitivity is highly prevalent in most functional bowel disorders, such as irritable bowel syndrome (IBS), and activation of intestinal mast cells (MC) may play a role because they have been found in close proximity to gastrointestinal mucosal sensory nerve terminals containing neuropeptides and a bi-directional pathway connecting the central nervous system, gut, and MC has been demonstrated. The current study appraised the status of rectal visceral perception, as well as the changes in the MC and substance P (SP) in the intestinal mucosa of patients with IBS. METHODS: The study group comprised 42 patients with IBS and 19 healthy subjects who underwent anorectal manometry and rectal perception thresholds to balloon distension. The MC and the SP-ergic terminals in the mucosa were stained for respective histochemical and immunohistochemical investigations. The results were presented both qualitatively and quantitatively by color image analyzer, based on analysis of the intensity and area of stained fibrils. The structural relationship between the MC and nerve terminals was studied by electron microscopy, using an in situ embedding technique. RESULTS: The anorectal resting pressure, squeezing pressure and relaxation pressure were normal in both groups. The sensation threshold, defecation threshold and pain threshold in diarrhea-predominant IBS and the pain thresholds in constipation-predominant IBS were much lower than in the controls. Rectal compliance decreased in IBS. The number of MC in the terminal ileum, the ileocecal junction and the ascending colon was significantly elevated in IBS (P < 0.01), and the MC showed great variation. A significantly increased concentration of SP was found in the colon of the IBS patients compared with the controls. There was a positive correlation between the profiles of mucosal MC and the SP-ergic terminals, and MC were closely adjacent to SP-ergic terminals in the lamina propria. CONCLUSION: As altered rectal perception is present in almost all patients with IBS, it might be a reliable biological characteristic of the disease. Alterations in the MC and SP of the intestinal mucosa may be important factors in visceral hypersensitivity.

Adult↗
PubMed2006

Randomized, controlled study comparing sitz-bath and no-sitz-bath treatments in patients with acute anal fissures.

AIM: To determine the efficacy and safety of sitz baths in the management of acute anal fissures. METHOD: Individual patients were randomized to either receive sitz baths or no sitz baths for 4 weeks in addition to oral psyllium husk. Patients were asked to soak their hips and buttocks in a tub containing plain lukewarm water for 10 min, once after defecation in the morning and again at bedtime. Each week, the patients were called to assess pain scores and healing of fissures, whereas the level of satisfaction was recorded at the end of 4 weeks. Main outcome measures were validated pain scores and levels of satisfaction. RESULTS: Fifty-eight subjects were recruited for this study. In all, 52 of them completed the trial (27 in the sitz bath group and 25 in the control group). Although the pain score was lesser in the sitz bath group than in the control group, it failed to reach statistical significance. There were no significant differences in fissure healing between the two groups over the 4-week study period. However, patients in the sitz bath group reported better satisfaction levels than the control group (P < 0.01). Although no serious adverse effects were observed, two patients from sitz bath group developed perianal skin rash. CONCLUSION: This study suggests that sitz baths improve patient satisfaction in acute anal fissures. However, the healing and overall pain relief was not significant enough to attract attention. It was also found to be associated with adverse effects in few patients.

Adolescent↗
PubMed2007

Anorectal three-dimensional endosonography and anal manometry in assessing anterior rectocele in women: a new pathogenesis concept and the basic surgical principle.

OBJECTIVE: The anatomy of the anal canal, the anorectal junction and the lower rectum was studied with 3-D ultrasound. METHOD: Seventeen women with normal bowel transit, without rectocele (group 1) and 17 female patients with a large anterior rectocele (group 2) were examined with a B&K Medical Rawk. Mean age was 44.5 and 51.6 years respectively. In group 1, one (5.8%) patient was nuliparous, five (29.4%) had a caesarian section, 11 (64.7%) had a vaginal delivery while in group 2, two (11.7%) patients were nuliparous, four (23.5%) had a caesarian section and 11 (64.7%) had a vaginal delivery. Images were reconstructed in midline longitudinal (ML) and transverse (T) planes. The external (EAS) and internal (IAS) anal sphincters were measured in both projections. RESULTS: In the ML plane, the EAS length was longer in group 1 (1.94 cm vs 1.61 cm, P < 0.05), the gap length was shorter (1.54 cm vs 1.0 cm P < 0.01) and the wall thickness was shorter in group 2 (0.40 cm vs 0.50 cm P < 0.01). The IAS (0.18 cm vs 0.23 cm P < 0.01) and EAS thickness (0.68 cm vs 0.77 cm, P < 0.05) (left lateral of the posterior quadrant) was greater in group 2. In group 1, the anterior upper anal canal wall in normal females was an extension of the rectal wall and the circular muscle was thicker in the mid-anal canal to form the IAS. In group 2, however, the wall layers were not identified and the IAS was found to be more distal. The differences were not statistically significant in the anal canal resting and squeeze pressures in the two groups. CONCLUSION: Obstetric trauma does not seem to play any role in rectocele pathogenesis because the anal sphincter muscles are anatomically and functionally normal and rectocele is also present in nuliparous and in women with caesarian sections. It seems that it is associated with the absence of EAS and thinner IAS in the anterior upper anal canal. Herniation starts at the upper anal canal extending to the lower rectum in high or large rectoceles and maybe produced by rectal intussusception because of excessive and prolonged straining during defecation. In fact, the denomination 'rectocele' should be changed to 'anorectocele'.

Adult↗
PubMed2005

Crossfostering in mice selectively bred for high and low levels of open-field thigmotaxis.

The main purpose of this research was to investigate whether the difference in open-field (OF) thigmotaxis between mice selectively bred for high and low levels of wall-seeking behavior originated from genetic or acquired sources. Unfostered, infostered, and crossfostered mice were compared in two experiments in which the effects of strain, sex, and fostering on ambulation, defecation, exploration, grooming, latency to move, radial latency, rearing, thigmotaxis, and urination were studied. These experiments revealed that OF thigmotaxis was unaffected by the foster condition and thus genetically determined. The selected strains of mice also diverged repeatedly with regard to exploration and rearing. The findings are in line with the previously described existence of an inverse relationship between emotionality and exploration.

Animal Husbandry↗