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An experimental study of bluff bodies in confinement is presented. Two Reynolds matched rigs (pipe diameters:
) are used to derive a picture of the flow topology of the primary-shedding mode (Kármán vortex, mode-I). Confined bluff bodies create an additional spectral mode (mode-II). This is caused by the close coupling of the shedder blockage and the wall and is unique to the confined bluff-body problem. Under certain conditions, modes-I and II can interact, resulting in a lock-on, wherein the modes cease to exist at independent frequencies. The topological effects of mode interaction are demonstrated using flow visualisation. Furthermore, the scaling of mode-II is explored. The two experimental facilities span Reynolds numbers (based on the shedder diameter,
and bulk Mach numbers
. Bluff bodies with a constant blockage ratio (
), forebody shape and various splitter-plate lengths (
) and thicknesses (
) are used. Results indicate that the flow topology changes substantially between short (
) and long (
) tailed geometries. Surface flow visualisation indicates that the primary vortex becomes anchored on the tail when
). This criterion prohibits the development of such a topology for short-tailed geometries. When mode interaction occurs, which it does exclusively in long-tailed cases, the tail-anchored vortex pattern is disrupted. The onset of mode-II occurs at approximately the same Reynolds number in both rigs, although the associated dimensionless frequency is principally a function of Mach number. Accordingly, mode interaction is avoided in the larger-scale rig, due to the increased separation of the modal frequencies.
Silicon nanowires (SiNWs) show unique optoelectronic properties such as band gap, radiative and nonradiative relaxations. In this research, the optoelectronic properties of <211> SiNW are calculated by combining time-dependent density matrix methodology. Description of photo-excited dynamics processes is enabled by computing “on–the–fly” nonadiabatic couplings (NAC) between electronic and nuclear degrees of freedom using density functional theory (DFT). The dynamics of electronic degrees of freedom is propagated by the reduced density matrix with Redfield equation of motion. Oscillator strengths are used to compute radiative relaxation and to generate time resolved photoluminescence (PL) spectrum. Analysis of the simulated nonradiative decay shows that high-energy photoexcitation relaxes to the band gap edge on the order of 1 ps. We also simulate time-resolved emission spectra of the <211> SiNW that reveals optical emissions above the optical band gap. These emission features are attributed to the interband transitions. The results of this study can be useful for the material choice for optoelectronic applications.
Optimal transition from child to adult services involves continuity, joint care, planning meetings and information transfer; commissioners and service providers therefore need data on how many people require that service. Although attention-deficit hyperactivity disorder (ADHD) frequently persists into adulthood, evidence is limited on these transitions.
To estimate the national incidence of young people taking medication for ADHD that require and complete transition, and to describe the proportion that experienced optimal transition.
Surveillance over 12 months using the British Paediatric Surveillance Unit and Child and Adolescent Psychiatry Surveillance System, including baseline notification and follow-up questionnaires.
Questionnaire response was 79% at baseline and 82% at follow-up. For those aged 17–19, incident rate (range adjusted for non-response) of transition need was 202–511 per 100 000 people aged 17–19 per year, with successful transition of 38–96 per 100 000 people aged 17–19 per year. Eligible young people with ADHD were mostly male (77%) with a comorbid condition (62%). Half were referred to specialist adult ADHD and 25% to general adult mental health services; 64% had referral accepted but only 22% attended a first appointment. Only 6% met optimal transition criteria.
As inclusion criteria required participants to be on medication, these estimates represent the lower limit of the transition need. Two critical points were apparent: referral acceptance and first appointment attendance. The low rate of successful transition and limited guideline adherence indicates significant need for commissioners and service providers to improve service transition experiences.
Schizophrenia is associated with robust hippocampal volume deficits but subregion volume deficits, their associations with cognition, and contributing genes remain to be determined.
Hippocampal formation (HF) subregion volumes were obtained using FreeSurfer 6.0 from individuals with schizophrenia (n = 176, mean age ± s.d. = 39.0 ± 11.5, 132 males) and healthy volunteers (n = 173, mean age ± s.d. = 37.6 ± 11.3, 123 males) with similar mean age, gender, handedness, and race distributions. Relationships between the HF subregion volume with the largest between group difference, neuropsychological performance, and single-nucleotide polymorphisms were assessed.
This study found a significant group by region interaction on hippocampal subregion volumes. Compared to healthy volunteers, individuals with schizophrenia had significantly smaller dentate gyrus (DG) (Cohen's d = −0.57), Cornu Ammonis (CA) 4, molecular layer of the hippocampus, hippocampal tail, and CA 1 volumes, when statistically controlling for intracranial volume; DG (d = −0.43) and CA 4 volumes remained significantly smaller when statistically controlling for mean hippocampal volume. DG volume showed the largest between group difference and significant positive associations with visual memory and speed of processing in the overall sample. Genome-wide association analysis with DG volume as the quantitative phenotype identified rs56055643 (β = 10.8, p < 5 × 10−8, 95% CI 7.0–14.5) on chromosome 3 in high linkage disequilibrium with MOBP. Gene-based analyses identified associations between SLC25A38 and RPSA and DG volume.
This study suggests that DG dysfunction is fundamentally involved in schizophrenia pathophysiology, that it may contribute to cognitive abnormalities in schizophrenia, and that underlying biological mechanisms may involve contributions from MOBP, SLC25A38, and RPSA.
The road to legalization of Medical Assistance in Dying (MAID) across Canada has largely focused on legislative details such as eligibility and establishment of regulatory clinical practice standards. Details on how to implement high-quality, person-centered MAID programs at the institutional level are lacking. This study seeks to understand what improvement opportunities exist in the delivery of the MAID process from the family caregiver perspective.
This multi-methods study design used structured surveys, focus groups, and unstructured e-mail/phone conversations to gather experiential feedback from family caregivers of patients who underwent MAID between July 2016 and June 2017 at a large academic hospital in Toronto, Canada. Data were combined and a qualitative, descriptive approach used to derive themes within family perspectives.
Improvement themes identified through the narrative data (48% response rate) were grouped in two categories: operational and experiential aspects of MAID. Operational themes included: process clarity, scheduling challenges and the 10-day period of reflection. Experiential themes included clinician objection/judgment, patient and family privacy, and bereavement resources.
Significance of results
To our knowledge, this is the first time that family caregivers’ perspectives on the quality of the MAID process have been explored. Although practice standards have been made available to ensure all legislated components of the MAID process are completed, detailed guidance for how to best implement patient and family centered MAID programs at the institutional level remain limited. This study provides guidance for ways in which we can enhance the quality of MAID from the perspective of family caregivers.
Tear staining (TS) in the pig has been related to different stressors and may be a useful tool for assessing animal welfare on farm. The aim of the current study was to investigate TS across the finisher period and its possible relation to age, growth, sex and experimentally induced stressors. The study included 80 finisher pens divided between three batches. Within each batch, the pens either included pigs with docked or undocked tails, had straw provided (150 g/pig/day) or not and had a low (1.21 m2/pig, 11 pigs) or high stocking density (0.73 m2/pig, 18 pigs). Tear staining (scores 1 to 4; from smaller to larger tear stain area, respectively) and tail damage were scored on each individual pig three times per week over the 9-week study period, and the individual maximum TS score within each week was chosen for further analysis. Data were analysed using logistic regression separately for each of the four possible TS score levels. The TS scores 1 and 2 decreased with weeks into the study period and were negatively related to the average daily gain (ADG) of the pigs, whereas the TS score 4 increased with weeks into the study period and was positively related to ADG. None of the TS scores differed between females and castrated males, and neither straw provision nor lowering the stocking density affected the TS scores. However, the TS score 1 decreased the last week before an event of tail damage (at least one pig in the pen with a bleeding tail wound), whereas the TS score 4 increased. The results of the current study advocates for a relation between TS and the factors such as age, growth and stress in the pig, while no relation was found between TS and the environmental factors straw provision and lowered stocking density. The relations to age and growth are important to take into consideration if using TS as a welfare assessment measure in the pig in the future.
Loose farrowing pens have been considered as alternatives to crates to enhance sow welfare. A major concern with pen systems is often higher piglet pre-weaning mortality, especially due to crushing by the sow. An optimal management of light and mat surface temperature may promote greater piglet use of the creep, which has been associated with reduced piglet crushing. A total of 108 sows and their piglets were studied in sow welfare and piglet protection pens on a commercial piggery, across two replicates. Sows were randomly assigned to pens arranged within two creep treatments (bright creep: 300 lx v. dark creep: 4 lx), considering mat temperature as a covariate. Twelve sows and their litters in each treatment (24 in total) had their behaviour continuously recorded for 72-h postpartum (pp), and four focal piglets per litter were weighed on the first and third days pp. In situ behaviour observations were performed daily (from 0800 to 1700 h) on all sows and their litters, every 15 min over 72-h pp to record piglet time spent in the creep, latency to enter the creep for the first time, latency for the litter to remain in the creep for at least 10 min, and piglet and sow use of pen areas immediately in front of (A2) and farthest from the creep (A3). Piglets with access to bright creeps spent on average 7.2% more time (P<0.01) in the creeps than piglets in pens with Dark creeps. In addition, for each degree increase in mat temperature, piglets spent on average 2.1% more time (P<0.01) in the creep. Piglets in pens with bright creeps spent less time in A2 (P=0.04) and the least time in A3 (P=0.01). Light or mat temperature did not affect sow use of pen areas or piglet weight gain. Piglets with bright creeps tended (P=0.06) to take longer to enter the creep for the first time after birth, but the latency for 30.0% of the litter to remain clustered for 10 min tended (P=0.08) to be shorter in bright compared to dark creeps. Overall, piglet use of the creep increased with warm mat temperatures and brightness, which should be further investigated as potential strategies to promote piglet safety and reduce crushing in pen farrowing systems.
Landraces (including heritage varieties) are an important agrobiodiversity resource offering considerable value as a buffer against crop failures, as a crop for niche markets, and as a source of diversity for crop genetic improvement activities underpinning future food security. Home gardens are reservoirs of landrace diversity, but some of the accessions held in them are vulnerable or threatened with extinction. Those associated with seed saving networks have added security, for example, ca. 800 varieties are stored in the Heritage Seed Library (HSL) of Garden Organic, UK. In this study, Amplified Fragment Length Polymorphisms-based genetic analysis of accessions held in the HSL was used to (a) demonstrate the range of diversity in the collection, (b) characterize accessions to aid collection management and (c) promote broader use of the collection. In total, 171 accessions were included from six crops: Vicia faba L., Pisum sativum L., Daucus carota L., Cucumis sativus L., Lactuca sativa L. and Brassica oleracea L. var. acephala (DC.) Metzq. Average expected heterozygosity ranged from 0.18 to 0.28 in D. carota; 0.02–0.18 in P. sativum; 0.05–0.18 in L. sativa; 0.15–0.26 in B. oleracea var. acephala; 0.15–0.37 in C. sativus and 0.07–0.36 in V. faba. Genetic diversity and Fst values generally reflected the breeding system and cultivation history of the different crops. Comparisons of the diversity found in heritage varieties with that found in commercial varieties did not show a consistent pattern. Principal coordinates analysis and Unweighted Pair Group Method with Arithmetic Mean cluster analysis were used to identify four potential duplicate accession pairs.
The Australian prehospital profession has not yet facilitated a comprehensive discussion regarding paramedic role and responsibility during disasters. Whether paramedics have a duty to treat under extreme conditions and what acceptable limitations may be placed on such a duty require urgent consideration. The purpose of this research is to encourage discussion within the paramedic profession and broader community on this important ethical and legal issue.
The authors employed qualitative methods to gather paramedic and community member perspectives in Victoria, Australia.
These findings suggested that both paramedic and community member participants agree that acceptable limitations on paramedic duty to treat during disaster are required. These limitations should be based on consideration of the following factors: personal health circumstances (eg, pregnancy for female paramedics); pre-existing mental health conditions (eg, posttraumatic stress disorder/PTSD); competing personal obligations (eg, paramedics who are single parents); and unacceptable levels of personal risk (eg, risk of exposure and infection during a pandemic).
It is only with the engagement of a more broadly representative segment of the prehospital profession and greater Australian community that appropriate guidance on limiting standards of care under extreme conditions can be developed and integrated within prehospital care in Australia.
SmithE, BurkleFM Jr., GebbieK, FordD, BensimonC. Acceptable Limitations on Paramedic Duty to Treat During Disaster: A Qualitative Exploration. Prehosp Disaster Med. 2018;33(5):466–470.
During vocalization, efference copy/corollary discharge mechanisms suppress the auditory cortical response to self-generated sounds. Previously, we found attenuated vocalization-related auditory cortical suppression in psychosis and a similar trend in the psychosis risk syndrome. Here, we report data from the final sample of early illness schizophrenia patients (ESZ), individuals at clinical high risk for psychosis (CHR), and healthy controls (HC).
Event-related potentials (ERP) were recorded from ESZ (n = 84), CHR (n = 71), and HC (n = 103) participants during a vocalization paradigm. The N1 ERP component was elicited during production (Talk) and playback (Listen) of vocalization. Age effects on N1 suppression (Talk–Listen), Talk N1, and Listen N1 were compared across groups. N1 measures were adjusted for normal aging before testing for group differences.
Both ESZ and CHR groups showed reduced Talk–Listen N1 suppression relative to HC, but did not differ from each other. Listen N1 was reduced in ESZ, but not in CHR, relative to HC. Deficient Talk–Listen N1 suppression was associated with greater unusual thought content in CHR individuals. N1 suppression increased with age in HC (12–36 years), and while CHR individuals showed a similar age-related increase, no such relationship was evident in ESZ.
Putative efference copy/corollary discharge-mediated auditory cortical suppression during vocalization is deficient in ESZ and precedes psychosis onset, particularly in CHR individuals with greater unusual thought content. Furthermore, this suppression increases from adolescence through early adulthood, likely reflecting the effects of normal brain maturation. This maturation effect is disrupted in ESZ, presumably due to countervailing illness effects.
There is a growing concern about the mental health of children and young people (CYP) in the UK, with increasing demand for counselling services, admissions for self-harm and referrals to mental health services. We investigated whether there have been similar recent trends in selected mental health outcomes among CYP in national health surveys from England, Scotland and Wales.
Data were analysed from 140 830 participants (4–24 years, stratified into 4–12, 13–15, 16–24 years) in 36 national surveys in England, Scotland and Wales, 1995–2014. Regression models were used to examine time trends in seven parent/self-reported variables: general health, any long-standing health condition, long-standing mental health condition; Warwick–Edinburgh Mental Wellbeing Score (WEMWBS), above-threshold Strengths and Difficulties Questionnaire Total (SDQT) score, SDQ Emotion (SDQE) score, General Health Questionnaire (GHQ) score.
Across all participants aged 4–24, long-standing mental health conditions increased in England (0.8–4.8% over 19 years), Scotland (2.3–6.0%, 11 years) and Wales (2.6–4.1%, 7 years) (all p < 0.001). Among young children (4–12 years), the proportion reporting high SDQT and SDQE scores decreased significantly among both boys and girls in England [SDQE: odds ratio (OR) 0.97 (0.96–0.98), p < 0.001] and girls in Scotland [SDQE: OR 0.96 (0.93–0.99), p = 0.005]. The proportion with high SDQE scores (13–15 years) decreased in England [OR 0.98 (0.96–0.99), p = 0.006] but increased in Wales [OR 1.07 (1.03–1.10), p < 0.001]. The proportion with high GHQ scores decreased among English women (16–24 years) [OR 0.98 (0.98–0.99), p = 0.002].
Despite a striking increase in the reported prevalence of long-standing mental health conditions among UK CYP, there was relatively little change in questionnaire scores reflecting psychological distress and emotional well-being.
Inefficiencies in the national clinical research infrastructure have been apparent for decades. The National Center for Advancing Translational Science—sponsored Clinical and Translational Science Award (CTSA) program is able to address such inefficiencies. The Trial Innovation Network (TIN) is a collaborative initiative with the CTSA program and other National Institutes of Health (NIH) Institutes and Centers that addresses critical roadblocks to accelerate the translation of novel interventions to clinical practice. The TIN’s mission is to execute high-quality trials in a quick, cost-efficient manner. The TIN awardees are composed of 3 Trial Innovation Centers, the Recruitment Innovation Center, and the individual CTSA institutions that have identified TIN Liaison units. The TIN has launched a national scale single (central) Institutional Review Board system, master contracting agreements, quality-by-design approaches, novel recruitment support methods, and applies evidence-based strategies to recruitment and patient engagement. The TIN has received 113 submissions from 39 different CTSA institutions and 8 non-CTSA Institutions, with projects associated with 12 different NIH Institutes and Centers across a wide range of clinical/disease areas. Already more than 150 unique health systems/organizations are involved as sites in TIN-related multisite studies. The TIN will begin to capture data and metrics that quantify increased efficiency and quality improvement during operations.
Group housing of gestating sows benefits their welfare by allowing them freedom of movement and the opportunity for social interaction. However, social life could also bring disadvantages for individuals who receive direct aggression or are displaced from the feeder. The aim of this study was to investigate associations between social behaviour, body condition and live weight. Gestating sows (n=298) were investigated on a commercial farm. Sows were housed in mixed parity groups where two single space, ad libitum trough feeders served 12 animals. Sows were weighed, body condition scored and had their back fat layer measured at mixing, 4 weeks after insemination and again before farrowing. Social status was estimated based on the numbers of won and lost agonistic interactions at mixing and at the end of gestation. In addition, tear staining was scored before the farrowing and reproductive performance data were collected. With the aid of video recordings, 100 to 150 interactions per group were observed. Winning percentage at mixing and at the end of gestation were associated (P<0.05) and appeared relatively stable within individuals. Tear staining scores and litter sizes were not associated with winning percentage at the end of gestation. However, live weight, relative weight, body condition and back fat thickness were associated with winning percentage (P<0.05), giving heavier animals an advantage. Low winning percentage related to lower live weight gain, probably due to poorer success in competition for feed. Live weight within a mixed parity group could be used as a proxy measure for social status. Sows with low body condition score and submissive sows might need special attention with regard to group dynamics and housing to alleviate the effects of competition in group housing.
OBJECTIVES/SPECIFIC AIMS: The objectives of this study were to compare different methods for determining the disciplines involved in a research article. We sought to address the following questions: To what extent does the number of disciplines reported by an article’s corresponding author agree with their description of the article as unidisciplinary or interdisciplinary? (Q1) and To what extent does the corresponding author’s description of the research as unidisciplinary or interdisciplinary agree with its classification as unidisciplinary or interdisciplinary based on the affiliation of its co-authors? (Q2). METHODS/STUDY POPULATION: Using Scopus, we randomly selected 100 articles from 2010 and 2015 from science teams that had at least 1 author affiliated with Johns Hopkins. Author affiliations were grouped into common academic disciplines: Basic Science, Medicine (and all clinical specialties), Public Health, Engineering, Social Science, Computer Science, Pharmacy, Nursing, and Other. Articles with more than 1 discipline were considered, interdisciplinary. We then sent an online Qualtrics survey to the corresponding author of each article and asked them to indicate (1) all of the disciplines that contributed to the research article at hand, and (2) to indicate whether they considered the research to be “unidisciplinary” or “interdisciplinary” based on definitions that we provided. RESULTS/ANTICIPATED RESULTS: For Q1, we asked corresponding authors to indicate the number of disciplines involved in their research and then to choose the definition that best described their research. Among 76 respondents, 42 indicated that their research consisted of 1 discipline, and 34 indicated that their research consisted of more than 1 discipline. Of the 42 respondents who indicated that their research consisted of one discipline, 21 (50%) respondents described their research as “unidisciplinary” and 21 (50%) described their research as “interdisciplinary.” However, of the 34 respondents who indicated that their research consisted of more than 1 discipline, all but 1 (97%) described their research as “interdisciplinary.” For Q2, we assigned a discipline to each co-author based on his/her affiliation and counted the number of disciplines involved. Among 76 respondents, of the 22 who described their research as “unidisciplinary,” 16 (73%) were categorized as “unidisciplinary” and 6 (27%) were categorized as “interdisciplinary,” using this method. Of the 54 respondents who described their research as “interdisciplinary,” 30 (56%) were categorized as “interdisciplinary” and 24 (44%) as “unidisciplinary.” DISCUSSION/SIGNIFICANCE OF IMPACT: Our results highlight that different methods for determining whether a given research article is interdisciplinary are likely to yield different results. Even when researchers indicate that their research is based within one major discipline, they may still consider it interdisciplinary. Likewise, classifying an article as either unidisciplinary or interdisciplinary based on the affiliations of its co-authors, may not be consistent with the way it is viewed by its authors. It is important to acknowledge that assessing the interdisciplinarity of research is complex and that objective and subjective views may differ.
Schizophrenia (SZ) is a severe neuropsychiatric disorder associated with disrupted connectivity within the thalamic-cortico-cerebellar network. Resting-state functional connectivity studies have reported thalamic hypoconnectivity with the cerebellum and prefrontal cortex as well as thalamic hyperconnectivity with sensory cortical regions in SZ patients compared with healthy comparison participants (HCs). However, fundamental questions remain regarding the clinical significance of these connectivity abnormalities.
Resting state seed-based functional connectivity was used to investigate thalamus to whole brain connectivity using multi-site data including 183 SZ patients and 178 matched HCs. Statistical significance was based on a voxel-level FWE-corrected height threshold of p < 0.001. The relationships between positive and negative symptoms of SZ and regions of the brain demonstrating group differences in thalamic connectivity were examined.
HC and SZ participants both demonstrated widespread positive connectivity between the thalamus and cortical regions. Compared with HCs, SZ patients had reduced thalamic connectivity with bilateral cerebellum and anterior cingulate cortex. In contrast, SZ patients had greater thalamic connectivity with multiple sensory-motor regions, including bilateral pre- and post-central gyrus, middle/inferior occipital gyrus, and middle/superior temporal gyrus. Thalamus to middle temporal gyrus connectivity was positively correlated with hallucinations and delusions, while thalamus to cerebellar connectivity was negatively correlated with delusions and bizarre behavior.
Thalamic hyperconnectivity with sensory regions and hypoconnectivity with cerebellar regions in combination with their relationship to clinical features of SZ suggest that thalamic dysconnectivity may be a core neurobiological feature of SZ that underpins positive symptoms.
Background: Lung cancer screening and tobacco treatment for patients at high-risk for lung cancer may greatly reduce mortality from smoking, and there is an urgent need to improve smoking cessation therapies for this population.
Aims: The purpose of this study is to test the efficacy of two separate, sequential interventions to promote tobacco cessation/reduction compared to standard care in smokers considered high-risk for lung cancer.
Methods: The study will recruit 276 current smokers attending a lung cancer screening clinic or considered high-risk for lung cancer based on age and smoking history across two sites. Patients first will be randomized to either standard tobacco treatment (8 weeks of nicotine patch and five individual counselling sessions) or standard tobacco treatment plus personalized gain-framed messaging. At the 8-week visit, all patients will be re-randomized to receive biomarker feedback or no biomarker feedback. Repeated assessments during treatment will be used to evaluate changes in novel biomarkers: skin carotenoids, lung function, and plasma bilirubin that will be used for biomarker feedback. We hypothesize that personalized gain-framed messages and receiving biomarker feedback related to tobacco cessation/reduction will improve quit rates and prevent relapse compared to standard care. Primary outcomes include 7-day point-prevalence abstinence verified with expired carbon monoxide at 8 weeks and mean cigarettes per day in the past week at 6 months.
Conclusions: Study findings will inform the development of novel interventions for patients at risk for lung cancer to improve smoking cessation rates.
It is generally accepted that routine invasive husbandry procedures, such as disbudding and dehorning, cause considerable distress in farmed animals. In the case of dehorning, it has repeatedly been shown that calves exhibit many pain related symptoms both during (e.g., withdrawal from noxious stimulus) the procedure and for some hours post procedure (e.g., rearing, tripping, head rubbing, etc.). Little is known about the long-term consequences of dehorning as previous studies have only monitored responses for up to 48 hours. The objectives of this work were to examine the long-term response of calves to hot-iron dehorning and to determine the effectiveness of non-steroidal anti-inflammatory drugs (NSAID) for reducing post-operative distress.
Wheat requires processing for feeding to cattle otherwise large amount remain undigested. Processing methods can be mechanical or chemical (sodium hydroxide or aqueous ammonia) but these require specialised equipment and/or the use of contractors. The objective of this trial was to evaluate moist wheat fed whole, but treated with urea at harvest as a means of generating ammonia in situ, in diets for intensively finished cattle.
Eighty tonnes of wheat (variety Riband) was harvested on 21-22 August 1997 at a dry matter (DM) of 750 g/kg and treated immediately with 53 l/tonne of a urea solution (430 g urea/litre) to supply 30 g urea/kg wheat DM. Treatment was achieved by applying the urea to the wheat as it was augered into the storage silo, which was then sealed with polythene.
Current commercial dairy practice involves the removal of the calf from the dam within the first two days of life. This early separation may result in stress for both cow and calf. However, it may also be that separation occurs before the cow-calf bond is established. The aim of this study was to determine if cows and calves respond to each other's calls after separation and whether they could distinguish their own calf's or dam's calls from another calf's or cow's calls.
The ‘standard’ human approach test has been used extensively since the early 1980's to assess fear responses in most farmed species. However, in recent years, there has been considerable debate questioning its efficacy given the short duration of the familiarisation period and the suitability of the location of the testing environment, i.e. the home pen versus a novel arena (Pedersen, 1997). It is possible that the test simply reflects an animal's level of motivation to explore the novel arena and any novel objects therein rather than a specific response to the presence of a human. This work addresses both the length of acclimatisation period and the location of the test arena.