Behavioural response to gastrointestinal parasites of yearling dairy calves at pasture.

AIMS: To investigate the association between gastrointestinal parasites (GIP) and animal behaviour in dairy calves under New Zealand pastoral conditions, using animal-mounted, accelerometer-based sensors. METHODS: Thirty-six, 5-6-month-old, Friesian-Jersey, heifer calves fitted with animal activity sensors to track behaviour were randomly allocated to one of two treatment groups. Half the animals were challenged with an oral dose of 20,000 larvae of Ostertagia ostertagi and Cooperia oncophera once a week for 3 weeks and half were unchallenged. Five weeks after the last dose, seven infected and nine uninfected animals were treated with an oral anthelmintic (AHC) and data collected for a further week. Accelerometer data were classified into minutes per day eating, ruminating, in moderate-high activity or in low activity. Live weight and faecal egg counts (FEC) were recorded weekly over the study period. All animals co-grazed a newly sown pasture not previously grazed by ruminants and were moved every week to fresh grazing. Treatment status was blinded to those managing the animals which were otherwise treated identically. RESULTS: Complete behavioural records were available from 30/36 calves, (13 challenged and 17 unchallenged). Before treatment with AHC, FEC increased in infected and un-treated calves over the study, while uninfected animals maintained a near zero FEC. There was no difference in live weight gain between the two groups over the study period. Bayesian, multinomial regression predicted differences in animal behaviour between infected and uninfected animals that were not treated with AHC over the 7 weeks following initial infection. Parasitised calves not treated with AHC were less active and spent up to 6 (95% highest density interval (HDI) = 1-11) minutes/day less in low level activity and up to 15 (95% HDI = 7-20) minutes/day less in moderate to high level activity. They ruminated up to 9 (95% HDI = 2-15) minutes/day more and ate up to 10 (95% HDI = 2-19) minutes/day more than control calves that were not treated with AHC. The effect of AHC on time spent in each behaviour differed between infected and uninfected calves and increased the coefficient of dispersion of the behavioural data. CONCLUSIONS AND CLINICAL RELEVANCE: Small differences in animal behaviour can be measured in calves with GIP. However, to use this to target treatment, further validation studies are required to confirm the accuracy of behavioural classification and understand the complex drivers of animal behaviour in a dynamic and variable pasture-parasite-host environment.

Revealing the diversity of internal body temperature and panting response for feedlot cattle under environmental thermal stress.

Core body temperature (CBT) regulation is crucial for mammalian wellbeing and survival. Cattle pant to dissipate excess heat to regulate CBT when ambient conditions exceed thermoneutral zones. However, to date, neither the variability in cattle heat response, the lagged response of CBT to thermal indices, nor the diurnal patterns of thermal indices, CBT and panting have been reported in the literature. We decomposed thermal indices, CBT and panting time-series data for 99 feedlot heifers across three discrete heat events into diurnal, trend and residual components. Both raw and decomposed data were analysed to explore the lagged CBT and panting responses and the association between series. We show ambient thermal conditions impact CBT with a 1-h lag despite a lag of between 1.5 to 3 h from raw data. Average individual panting scores were used to identify heat-susceptible and heat-tolerant cattle. Heat-susceptible cattle showed greater CBT (P < 0.01) between 8:00 and 23:00 and greater panting duration (P < 0.05) between 10:00 and 18:00 than heat-tolerant cattle under the same thermal conditions and these variations followed a similar pattern despite differences in cattle breed. This new information enables targeted amelioration and selection of individuals against heat susceptibility.

Timing of eating during transition impacts feedlot cattle diet and liveweight gain.

The timing of eating, relative to when feed is offered, is affected by the social rank of feedlot cattle due to limited feed bunk space. As cattle can select feed based on dietary preference, the timing of eating for cattle in feedlot may be associated with the ingested diet composition. Our objectives were to determine the nutritive value and timing of feed ingested by 100 feedlot cattle during transition and the association of timing of eating with feeding behaviours and average daily gain (ADG). Cattle behaviour and timing of eating were determined on 100 feedlot cattle using accelerometer-based ear tag sensors from days 3 to 6 post feedlot induction (observation period), and the ongoing impact of this period on ADG was determined for the full feed period (75 days). To determine eating patterns at the time of feed offer, cattle were grouped according to the number of days they were recorded as eating within 1 h of feed being offered across 4 observation days, G0: not present across 4 days, G1: present for 1 day, G2: 2 days, G3: 3 days and G4: present for each of the 4 days. Total mixed ration (TMR) samples were collected for nutritive value analysis from four locations along the feed bunk from the time feed was offered and at hourly intervals thereafter for 7 h each day during the observation period. The composition of feed in the bunk changed across the 7 h of measurement (P < 0.05). The DM and CP of feed increased from 65 to 70% and 15 to 16%, respectively, and the NDF decreased from 36 to 32%. Thus, the preferred TMR feed component was the fibrous dietary fraction. However, the overall composition of the ingested diet for 7 h post feeding was similar between groups. Cattle in G0 had reduced eating time (0.7 vs 4.8%; P < 0.001), rumination time (4.5 vs 19.5%; P < 0.001) and ADG (1.0 vs 1.3 kg/d; P < 0.05) across the study, as compared with cattle in G4. Offering a more fibrous ration during feedlot transition, and customised cattle segregation and/or customised feeding regimes based on sensor derived feeding behaviour profiles during acclimation to feedlot can optimise ADG, animal welfare and feedlot profit.

The origin and foot condition of horses slaughtered in Australia for the human consumption market.

REASONS FOR PERFORMING STUDY: There are ethical concerns regarding the loss of horses from various equine industries and their corresponding slaughter. However, to date, no empirical evidence regarding the extent of this loss, nor of the condition of horses involved, exists within Australia. OBJECTIVES: To determine the approximate ages, brand type and condition of feet of horses relinquished to an export abattoir in Australia. METHOD: Data were collected from 340 horses processed at an Australian abattoir from November 2007-January 2008. Foot abnormalities, injuries and hoof indicators of overgrown and untrimmed hooves were assessed together with a dental inspection. Observations of brand were used to determine horse origin. RESULTS: The dental age of 60% of horses was 57 years, and 53% originated from the racing industry (40% Thoroughbred and 13% Standardbred). A total of 81% of the horses had overgrown or untrimmed hooves. Standardbred horses had fewer grass cracks and more injuries to the coronary band than Thoroughbreds, probably due to pacing and trotting activities. CONCLUSIONS: Just over half of the horses slaughtered at an Australian abattoir on 3 working days were aged (7 years and emanated from the racing industry. Foot problems were common. POTENTIAL RELEVANCE: Future research should identify means of reducing the number of horses slaughtered and preventative measures for foot disorders.

Resistance to change of operant variation and repetition.

A multiple chained schedule was used to compare the relative resistance to change of variable and fixed four-peck response sequences in pigeons. In one terminal link, a response sequence produced food only if it occurred infrequently relative to 15 other response sequences (vary). In the other terminal link, a single response sequence produced food (repeat). Identical variable-interval schedules operated in the initial links. During baseline, lower response rates generally occurred in the vary initial link, and similar response and reinforcement rates occurred in each terminal link. Resistance of responding to prefeeding and three rates of response-independent food delivered during the intercomponent intervals then was compared between components. During each disruption condition, initial- and terminal-link response rates generally were more resistant in the vary component than in the repeat component. During the response-independent food conditions, terminal-link response rates were more resistant than initial-link response rates in each component, but this did not occur during prefeeding. Variation (in vary) and repetition (in repeat) both decreased during the response-independent food conditions in the respective components, but with relatively greater disruption in repeat. These results extend earlier findings demonstrating that operant variation is more resistant to disruption than is operant repetition and suggest that theories of response strength, such as behavioral momentum theory, must consider factors other than reinforcement rate. The implications of the results for understanding operant response classes are discussed.

Superstitious responding and reinforcement rate under concurrent variable-interval extinction schedules.

To examine superstitious responding, four pigeons key pecked under multiple concurrent variable-interval 45 s variable-interval 90 s concurrent variable-interval 90 s variable-interval 180 s schedules in the absence of a changeover delay. The two variable-interval 90 s schedules then were replaced by extinction, and key-peck responding during extinction was examined as a function of the prevailing reinforcement rate. During the first several sessions, extinction-key responding was maintained closer to baseline levels in the presence of the higher reinforcement rate, and this effect dissipated or even reversed with continued exposure to extinction. Although extinction-key responding generally decreased to near-zero levels after several sessions, in a few instances, it continued for 30 and 45 sessions. These results demonstrate how concurrent variable-interval extinction schedules can be used to investigate what often has been labeled superstitious responding.

A survey of primary care physician practice patterns and adherence to acute low back problem guidelines.

OBJECTIVE: This study evaluated physicians' self-reported management of acute low back problems in adults and adherence with published guidelines. DESIGN: Self-administered written survey based on the US Agency for Health Care Policy and Research (now the Agency for Healthcare Research and Quality) guideline on acute low back problems in adults. SETTING: A region of northern Illinois with a population around 250 000 and encompassing a medium-sized city. PARTICIPANTS: One hundred eighty-two primary care physicians (nonpediatric) with medical staff appointments at area hospitals. MAIN OUTCOME MEASURE: Adherence to published recommendations. RESULTS: Eighty-seven surveys were received for a 48% response rate. Overall, survey respondents recognized 5 of 7 red flags representing serious underlying abnormality 50% or less of the time. Forty percent (35/87) of physicians provided patients with written educational material, and only 25%(22/87) indicated they evaluated motor function of the fifth lumbar nerve, the most commonly affected level in intervertebral disk disease disease. About 25% (24/87) reported routine use of plain films; and 16% (14/87), routine use of computed tomography or magnetic resonance imaging. Most oral medication use was consistent with recommendations, but many also used drugs conditionally discouraged by the guideline (muscle relaxants, 91% [79/87]; opioids, 62% [54/87]) or cautioned against (oral steroids, 45% [39/87]; antidepressants, 23% [20/87]; injection therapy, 52% [45/87]). Only 22% (19/87) of respondents used or recommended manipulation. CONCLUSIONS: The management of patients with acute low back problems by primary care physicians differs significantly from Agency for Health Care Policy and Research guideline recommendations in several key areas that include awareness of red flags, use of medication, use of radiographic studies, the need for patient education, and the use of physical modalities. Future research should focus on the impact of guideline compliance on patient outcomes and cost-effectiveness. Arch Fam Med. 2000;9:1015-1021

Spontaneous clearance of hepatitis C virus infection post-liver transplantation is associated with rapidly changing quasispecies: a single case report.

Hepatitis C virus (HCV) clearance post-liver transplantation is uncommon. This is a case report of a patient who, after liver transplantation, developed cholestatic hepatitis characterized by severe graft dysfunction, in conjunction with high viral load. This was, however, followed by viral clearance and normalization of allograft function. The clinical features of this case and the quasispecies patterns during the illness and the clearance periods are described. In addition, management implications in terms of immunosuppressive therapy are discussed.

Manitoba aboriginal kindred with original cerebro-oculo- facio-skeletal syndrome has a mutation in the Cockayne syndrome group B (CSB) gene.

Cerebro-oculo-facio-skeletal (COFS) syndrome is a rapidly progressive neurological disorder leading to brain atrophy with calcification, cataracts, microcornea, optic atrophy, progressive joint contractures, and growth failure. Cockayne syndrome (CS) is a recessively inherited neurodegenerative disorder characterized by low-to-normal birth weight; growth failure; brain dysmyelination with calcium deposits; cutaneous photosensitivity; pigmentary retinopathy, cataracts, or both; and sensorineural hearing loss. CS cells are hypersensitive to UV radiation because of impaired nucleotide excision repair of UV radiation-induced damage in actively transcribed DNA. The abnormalities in CS are associated with mutations in the CSA or CSB genes. In this report, we present evidence that two probands related to the Manitoba Aboriginal population group within which COFS syndrome was originally reported have cellular phenotypes indistinguishable from those in CS cells. The identical mutation was detected in the CSB gene from both children with COFS syndrome and in both parents of one of the patients. This mutation was also detected in three other patients with COFS syndrome from the Manitoba Aboriginal population group. These results suggest that CS and COFS syndrome share a common pathogenesis.

Post-transplant quasispecies pattern remains stable over time in patients with recurrent cholestatic hepatitis due to hepatitis C virus.

BACKGROUND/AIMS: Several studies have shown that cholestatic recurrent hepatitis is associated with very high HCV RNA loads in liver transplant recipients. The aim of this study was to investigate whether a correlation exists between cholestatic hepatitis post-transplant and the population of viral quasispecies. METHODS: One hundred and nine serial sera samples were tested from 15 recurrent HCV patients. Four of these patients showed severe cholestatic recurrent hepatitis, 11 patients demonstrated non-cholestatic recurrent hepatitis post-transplant. Quasispecies were detected by RT-PCR amplification of the HVR1 followed by single-stranded conformational polymorphism analysis. RESULTS: Forty-one samples from four cholestatic patients were tested. All four patients showed very stable quasispecies patterns post-transplant. One cholestatic patient also showed a stable quasispecies band pattern following retransplantation, again associated with severe cholestatic hepatitis. Sixty-eight samples were tested from the 11 non-cholestatic patients. In contrast, these patients showed significantly more quasispecies bands than the cholestatic patients. The noncholestatic patients also displayed fluctuating band patterns post-transplant. Serial samples were tested after retransplantation in one non-cholestatic patient, with a fluctuating pattern again seen. There was a negative correlation between the HCV RNA load in serum and the number of quasispecies bands. CONCLUSIONS: Stable hepatitis C viral quasispecies associated with persistently high viral load in post-transplant cholestatic hepatitis suggest that viral escape from immune pressures may play a role in the pathogenesis of this condition.

Nonspecificity of monoclonal antibody Tordji-22 for the detection of hepatitis C virus in liver transplant recipients with cholestatic hepatitis.

Detection of hepatitis C virus (HCV) antigens in liver tissue provides important diagnostic and pathological information. Limited studies have been performed on tissue taken after liver transplantation for HCV. In this study, serial post-liver transplantation biopsy tissue from patients with recurrent HCV was tested, with particular interest in patients showing severe cholestatic hepatitis. HCV-related antigens were detected using the commercial monoclonal antibody, Tordji-22. Initial results were promising, showing intense positive staining, especially in areas of hepatocyte ballooning. HCV-negative donor tissue was consistently negative by staining. However, as a final control for the level of tissue damage, HCV negative posttransplantation biopsy tissue showing hepatocyte ballooning was examined. These tissues also showed positive staining. All attempts to eliminate this nonspecific interaction failed. In conclusion, Tordji-22 was associated with nonspecificity in this posttransplantation population, and care is warranted when using this monoclonal antibody.

Premenstrual symptoms. Prevalence and severity in an adolescent sample.

PURPOSE: To survey the prevalence and severity of premenstrual symptoms and compare premenstrual symptom clusters of younger (13-15-year-old) and older (16-18-year-old) adolescents, based on both chronological and gynecological age. METHODS: Physical, emotional, and behavioral premenstrual symptoms were assessed by self-report using the Premenstrual Assessment Form (PAF), in a sample of 75 adolescents. Analyses were performed to determine differences in premenstrual symptom clusters in younger and older adolescents. RESULTS: The participants had a mean age of 14.8; 96% identified themselves as Caucasian, 3% as African-American, and 1% as Asian. All participants reported at least one premenstrual symptom of minimal severity. Many reported symptoms that they considered moderate (88%), severe (73%), or extreme (56%). The symptoms most commonly reported were food cravings, breast swelling, abdominal discomfort, mood swings, stressed feeling, and dissatisfaction with appearance. Other symptoms, such as missing time at school, becoming violent with people or things, and "thinking of what it would be like to do something to self" (such as crash the car), wishing to go to sleep and not wake up, or having thoughts of death or suicide, were less frequently reported. The younger teens (13-15 years old) had significantly less intense symptoms than the older teens (16-18 years old). CONCLUSIONS: Premenstrual symptoms reported as being moderate or greater in severity were found to be quite prevalent (88%) in this sample of adolescents. Specifically those adolescents at 41 months postmenarche or greater reported specifically more intense premenstrual symptoms. In addition, a subset of adolescents expressed that they experienced aberrant behavior and passive suicidal ideations as premenstrual symptoms.

Cholestatic hepatitis after liver transplantation is associated with persistently high serum hepatitis C virus RNA levels.

Viral recurrence is universal after transplantation for hepatitis C infection. This may lead to difficulties in differentiating allograft dysfunction caused by chronic rejection from hepatitis C virus (HCV) recurrence. Cases of severe cholestatic hepatitis have also been reported in conjunction with reinfection of the graft with HCV. Patients receiving transplants for HCV-related liver disease were studied before and after transplantation by HCV RNA quantitation of serial serum samples. Four major clinical patterns of HCV recurrence could be distinguished posttransplantation: group 1, asymptomatic hepatitis with no significant symptoms; group 2, cholestatic hepatitis with centrilobular ballooning; group 3, hepatitis leading to chronic allograft rejection; and group 4, persistently normal serum aminotransferase levels. Pretransplantation viral load was shown to be an important indicator of disease severity because the group 2 patients had significantly higher pretransplantation viral loads than patients in group 1 (P = 0.01) and group 4 (P = 0.005). The group 2 patients also had persistently significantly higher posttransplantation viral loads than the patients in group 1 (P = 0.01) and group 4 (P = 0.02), whereas patients who developed chronic allograft rejection showed marked decreases in serum HCV RNA before retransplantation. Patients from group 4 had the lowest viral loads after transplantation. These results show that persisting graft cholestasis due to HCV is associated with persistently high HCV RNA levels compared with other etiologies of graft dysfunction. Prospective studies are needed to determine whether such quantitation may be diagnostically helpful in distinguishing the different patterns of HCV-related graft dysfunction observed after liver transplantation.

Risk factors for fecal incontinence in a nursing home population.

Even though fecal incontinence is a leading cause of nursing home placement, risk factors contributing to its development have not been established. Identification of such factors may lead to prevention of incontinence and reduce the need for nursing home placement. A total of 388 residents of five nursing homes were included. Data regarding mental status, bowel habits, obstetrics history, and the presence, frequency, and severity of fecal incontinence were collected for each participant. Of the 388 nursing home residents, 46% were incontinent of feces. Incontinence was 1.5 times more common in males and in those younger than 65 years of age. In both univariate and multivariate analyses, diarrhea, dementia, restricted mobility, and male gender were independently associated with incontinence. In contrast to previous studies, constipation was not associated with fecal incontinence. If elimination of these risk factors leads to prevention of incontinence in even a few people, some elderly patients may not require institutionalization, which will result in improvement in their quality of life, not to mention a reduction in public health expenditures.

Assessment at one school of students' abilities and confidence in diabetic patients' education.

PURPOSE: To determine medical students' experiences in working with diabetic patients, their cognitive competence and their confidence in meeting diabetic patients' educational needs, and changes in their expertise with advancing education. METHOD: The study was conducted in March 1994 at the University of Illinois College of Medicine, where students work with ambulatory patients in a longitudinal primary care experience from their second year through graduation. A combined questionnaire and objective quiz was developed and distributed to 138 second-, third-, and fourth-year students. The students were asked whether they had had experience in seeing a newly diagnosed diabetic patient, in what setting, and whether they felt confident in educating such patients on various common topics. They were also asked about their interests in and preferences for learning about diabetic patients' education. A 50-item objective quiz on the management of diabetes followed the questionnaire. Data were analyzed with several statistical methods. RESULTS: In all, 65 of the students (47%) responded; the majority were third- or fourth-year students. The percentages of students who felt confident ranged from 83% who felt confident about counseling about exercise to only 16% who felt confident about pre-conception counseling. All of the students but one felt that diabetic patients' education was an important topic, and all but two were interested in it. The students' quiz scores showed no significant difference by year of training; for all the students the average score was 39.6% correct, with no increase in score for increased training. Also, the students who were more confident about their abilities to provide patient education on a certain topic were no more likely to have accurate information about that topic than were those who were not confident. CONCLUSION: Although they were clearly interested in diabetic patients' education, the students did not feel confident in providing it, nor did they have the cognitive competence to do so. Medical schools have a responsibility to students and to their patients to formally address the issues of patient education.

Synergistic interactions between XPC and p53 mutations in double-mutant mice: neural tube abnormalities and accelerated UV radiation-induced skin cancer.

The significance of DNA repair to human health has been well documented by studies on xeroderma pigmentosum (XP) patients, who suffer a dramatically increased risk of cancer in sun-exposed areas of their skin [1,2]. This autosomal recessive disorder has been directly associated with a defect in nucleotide excision-repair (NER) [1,2]. Like human XP individuals, mice carrying homozygous mutations in XP genes manifest a predisposition to skin carcinogenesis following exposure to ultraviolet (UV) radiation [3-5]. Recent studies have suggested that, in addition to roles in apoptosis [6] and cell-cycle checkpoint control [7] in response to DNA damage, p53 protein may modulate NER [8]. Mutations in the p53 gene have been observed in 50% of all human tumors [9] and have been implicated in both the early [10] and late [11] stages of skin cancer. To examine the consequences of a combined deficiency of the XPC and the p53 proteins in mice, we generated double-mutant animals. We document a spectrum of neural tube defects in XPC p53 mutant embryos. Additionally, we show that, following exposure to UV-B radiation, XPC p53 mutant mice have more severe solar keratosis and suffer accelerated skin cancer compared with XPC mutant mice that are wild-type with respect to p53.

Objective measurements of compliance in asthma treatment.

BACKGROUND: Self-management protocols and home peak expiratory flow rate monitoring are thought to improve asthma care. OBJECTIVE: Compliance and accuracy of patients' record keeping were measured during a guided self-management protocol. Video, face-to-face instruction, and written protocols were part of the educational program. METHODS: Twenty patients participated in a 5-week study using memory capable peak expiratory flow rate meters and inhalers. During the baseline week all patients followed their customary approach to treatment and kept written diaries of peak expiratory flow rate and inhaler usage results; thereafter, they followed an individually designed self-management protocol. RESULTS: Good technique and knowledge were found during the baseline visit and improved by the last visit. Compliance with the protocol during the fifth week occurred in 40% of patients with underusage of inhalers in 50% and overusage in 10% despite allowing for a 10% inaccuracy in recording. Patients keeping inaccurate records early in care tend not to improve. Errors in recording inhaler usage increased from 47% to 58% of days during the final week. Patients inflated peak expiratory flow rate scores (P < .01) over time. Slight improvement in the peak expiratory flow rate was found for the entire group (baseline week 371 L/min versus final week 386 L/min P < .05). CONCLUSIONS: Despite an extensive educational program in the self-management of asthma, compliance with recommended treatment was only 40%. Electronic monitoring of peak expiratory flow rate and inhaler usage can provide early identification of patients who do not comply.