RSS 1.0Biological Sciences
The Department of Biological Sciences has an expanding research base, which, in addition to providing leading researchers of national and international standing in these areas, most importantly underpins the delivery of teaching. Research in Biological Sciences at Chester can be divided into three broad groups of expertise, namely Animal Behaviour and Conservation, Food Nutrition and Health, and Stress and Disease.
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Open Carboniferous Limestone pavement grike microclimates in Great Britain and Ireland: understanding the present to inform the futureLimestone pavements are a distinctive and irreplaceable geodiversity feature, in which are found crevices known as grikes. These grikes provide a distinct microclimate conferring a more stable temperature, higher relative humidity, lower light intensity and lower air speed than can be found in the regional climate. This stability of microclimate has resulted in an equally distinctive community of flora and fauna, adapted to a forest floor but found in an often otherwise barren landscape. This thesis documents the long-term study of the properties of the limestone pavement grike in order to identify the extent to which the microclimate may sustain its distinctive biodiversity, to provide recommendations for future research which may lead to more effective management. Over a five-year study, recordings of temperature, relative humidity, light intensity and samples of invertebrate biodiversity were collected from five limestone pavements situated in the Yorkshire Dales and Cumbria in Great Britain, and The Burren in the Republic of Ireland. An extensive description of the grike microclimate was undertaken using the data collected to understand the extent of the microclimate stability of the grike and the conditions for variation in the grike microclimate. Further insights into the grike microclimate were gained through simulation techniques more commonly used in engineering, to explore the effects of air flowing over a grike, the light from the sun entering the grike and regression analysis to simulate the temperature within the grike in the present and projected for the future. This study has indicated that although the whole of the grike confers a degree of microclimatic stability, it is made up of a less stable upper zone and a more stable lower zone. The instability of the upper zone is hypothesised to result from the extent to which the majority of light and external air can enter the grike, whereas the stability of the lower zone may be governed by the thermal stability of the limestone surrounding it. Based on this zonation and the projections for the grike temperature, it is hypothesised that climate change will have the most substantial effects in the upper grike zone where species obligated to this area could be most heavily impacted. This study recommends a range of areas in which research may be employed so that the limestone pavement habitat may be successfully managed in Great Britain and the Republic of Ireland.
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The importance of long-term genetic monitoring of reintroduced populations: inbreeding in the natterjack toad (Epidalea calamita)Genetic monitoring is an important, but frequently lacking, component of management actions to support long-term persistence in reintroduced populations. Populations that remain small, due to demographic processes and genetic diversity, are more likely to experience a second extinction event. The natterjack toad (Epidelea calamita) is legally protected in Britain and was the subject of a reintroduction programme in the 1990s. However, subsequent genetic assessment has been mostly lacking. The aim of this study was to assess the genetic diversity of two reintroduced populations of natterjack toads in order to inform conservation management. Adults were sampled and nine microsatellites amplified to assess neutral genetic variation within each site and for comparison with the source population. Inbreeding was observed at the reintroduction sites, as evidenced by high FIS values (0.43 and 0.72), low observed compared to expected heterozygosities, and significant deviation from Hardy-Weinberg equilibrium. Observed heterozygosity is currently lower in the reintroduction sites than it was in the source population at the time of the reintroductions (Red Rocks: 0.15±0.20; Talacre: 0.12±0.20; Ainsdale (source): 0.29). Evidence for a bottleneck was not found, although this is likely a result of sampling overlapping generations. No within-site population structuring was observed. Such low genetic diversity has not previously been recorded in any natterjack population. Genetic rescue, combined with pool creation, is the most viable option for safeguarding the species at these sites into the future. Our work highlights the importance of ongoing genetic monitoring, in collaboration with conservation organisations, to support conservation management.
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Patterns in island endemic forest-dependent bird research: the Caribbean as a case-studyAbstract: Unequal patterns in research effort can result in inaccurate assessments of species extinction risk or ineffective management. A group of notable conservation concern are tropical island endemic birds, many of which are also forest-dependent, which increases their vulnerability to extinction. Yet, island bird species have received limited research attention compared to their continental congeners, despite this taxon being globally regarded as well-studied. We used the insular Caribbean, a globally important endemism hotspot with high rates of deforestation, to explore research bias of island and regional endemic forest-dependent birds. A review of the published literature (n = 992) found no significant increase in the number of studies over the search period. Research effort was significantly higher among species with threatened status, long generation time, wide habitat breadth and low to intermediate elevational distributions. Among family groups, the Psittacidae received the highest research effort, while the Cuculidae were the most underrepresented family (30-fold higher and six-fold less than expected, respectively). We found geographic biases in effort, with Jamaica having six-fold less and Puerto Rico eight times more research than expected for their level of endemism. These patterns likely reflect individual interests and limited capacity and funding, typical of Small Island Developing States. With over 50% of species in this review having declining population trends, we recommend prioritizing research that emphasises conservation- and management-relevant data across underrepresented families and islands, by fostering greater collaboration between researchers, practitioners and the existing local amateur ornithological community.
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The Functionality of “Ogi” – a fermented cereal gruel made in Nigeria, in the Management of Gastrointestinal DiseaseFermentation is an ancient food processing technique which has over the years had significant impact on food availability, production, economy and health. Fermented corn, ‘ogi’, is a popular meal in South and West African countries and is also traditionally administered to people, especially children, during the incidence of diarrhoea as it is believed to enhance gut health. Various authors have supported the advantageous health functions of fermented corn but have focussed on the possible health benefits that may be derived from the action of the fermentation organisms by investigating their probiotic potentials. Furthermore, in vivo studies have investigated effective functionality of fermented foods and where studies have suggested positive effect of the fermented food intervention, the component of the complex food matrix that may be responsible is often unknown. Though hypothesised, there has been little information on the possible effects of the end products of the fermentation on gut health. Therefore, this thesis aimed to explore the functionality potentials for ‘ogi’, to enhance gut health by investigating the mechanisms through which it may be able to confer the health benefits when consumed. An independent meta-analysis was undertaken to explore and review the analysis of the effectiveness of fermented foods to significantly reduce the duration of diarrhoea. The first experimental study was a comparison between spontaneously fermented vs controlled method of ‘ogi’ production with the aim to explore the possibility of achieving similar end products. The probiotic potential of fermentation organisms and antimicrobial effect of fermentation organisms against E. coli were also investigated. Colonic short chain fatty acids (SCFAs) are known to enhance immune function in the gut. The second experimental study explored the production of SCFAs in fermented corn with the theory that fermented corn may be a dietary source of SCFA and may produce a comparable effect in the gut as the colonic SCFA. It is established that one of the functions of endogenously synthesised nitric oxide (NO) in the body is to enhance immune functions. Therefore, the potential for ‘ogi’ to enhance immune response in the gut by being a dietary source of Nitric Oxide (NO) was explored in the third experimental study. The outcomes of this thesis suggest that it may not be possible to mimic the exact spontaneous fermentation process in a controlled setting. Weissella confuse, Pediococcus pentosaceus and Saccharomyces cerevisiae were the lactic acid bacteria (LAB) and yeast isolated from spontaneously fermented corn using 16S rRNA sequencing. The isolated organisms along with Lactobacillus plantarum were used as starter culture for controlled fermentation. There was a significant difference between the end products of both fermentations. All organisms except W. confuse showed probiotic potential. Acetate was produced during both fermentations but butyrate was produced during spontaneous fermentation only. There was however higher concentration of NO in controlled fermented corn than spontaneous fermentation with nitrate values of 30.54 µM and 23.21 µM and nitrite values of 17.50 µM and 10.11 µM respectively. These suggest that fermented corn may have probiotic potential and may be able to further enhance immune health in the gut by being a dietary source of SCFAs and NO.
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Mangrove or mudflat: Prioritising fish habitat for conservation in a turbid tropical estuaryMangrove habitats are typically the focus of conservation efforts in tropical estuaries because their structural complexity is thought to support greater biodiversity and nursery function than unvegetated habitats. However, evidence for this paradigm has been equivocal in turbid tropical estuaries where unvegetated mudflats are also highly productive. The present study compared the community composition, biodiversity, nursery-role and commercial fish biomass in two mangrove habitats and one mudflat habitat in the Gulf of Paria, Trinidad. A total of 12 705 fishes, comprising 63 species from 26 families, were sampled in mangrove creeks, seaward mangrove fringe and the subtidal margin of an intertidal mudflat from June 2014 to June 2015. The composition of the creek and mudflat communities were distinct, while the community of the mangrove fringe more closely resembled the mudflat than the mangrove creeks. Mean species richness (MSR), total species richness (TSR) extrapolated from species accumulation curves, and juvenile species richness (JSR) were significantly greater in the mudflat (MSR = 11.4 ± 1.0; TSR = 75 ± 14; JSR = 9.1 ± 0.8) than mangrove creeks (MSR = 9.0 ± 0.5; TSR = 49 ± 3; JSR = 6.1 ± 0.4) and the seaward mangrove fringe (MSR = 6.4 ± 0.7; TSR = 58 ± 14; JSR = 5.2 ± 0.4). Meanwhile, Shannon Weiner diversity, juvenile fish abundance and commercial fish biomass were comparable between habitats. These findings caution against the generalisation that mangroves are the most important habitat for fishes in turbid tropical estuaries. There is now a growing body of evidence that mudflats warrant consideration as important repositories of biodiversity and nursery function for juvenile fishes.
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A review of tropical dry forest ecosystem service research in the Caribbean – gaps and policy-implicationsTropical dry forests (TDFs) are globally threatened, yet remain poorly studied. In the Caribbean, the most biodiverse of island biodiversity hotspots, TDFs have structural properties distinct from the Neotropical mainland and are important to local communities for ecosystem services. We undertook a systematic review (n = 186) of ecosystem services literature of Caribbean TDF. Only 19.89% qualified for inclusion, with the majority (56.76%) from primary literature. Research on supporting services (31.14%), particularly primary production was predominant. Most studies (70.97%) took a biophysical perspective and quantification focused on the supply of ecosystem services (43.00%), while measurement of wellbeing benefits were uncommon. Geographic coverage of all studies was patchy originating from only nine of 28 independent countries and dependent territories. Our findings highlight a lack of research, while accentuating the value of grey literature in quantifying cultural services. Of concern, are gaps in air- and water-related services and the importance of TDF to human health. To move from biophysical assessments to a broader portfolio of ecosystem services studies, research on Caribbean TDF should be collaborative and strategic. Such gaps and research biases suggest opportunities for evidence-led policy-making. These lessons are relevant for mainstreaming ecosystem services into decision-making in Small Island Developing States.
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Current strength, temperature, and bodyscape modulate cleaning services for giant manta raysThe cleaner-client system among reef teleosts has received considerable attention in both wild and captive environments, but the spatially and taxonomically diverse associations between cleaner fish and elasmobranchs are less understood. Using remote video, we investigated interactions between giant manta rays (Mobula birostris) and cleaner wrasse at a seamount in the Philippines. Cleaning events occurred between 11:00 and 16:00 hours on a seasonal basis and were constrained by current strengths and ambient water temperatures. The frequency with which giant manta rays interacted with cleaner fish varied on an individual basis. Blue streaked cleaner wrasse (Labroides dimidiatus) and moon wrasse (Thalassoma lunare) selectively foraged on manta rays’ gills and pelvis, with L. dimidiatus also demonstrating slight preferences for the pectoral fins. Cleaners’ foraging preferences may indicate ectoparasitic infections in specific areas of a manta ray’s body. The exclusivity with which giant manta rays visited a particular cleaning station on the seamount may be a response to the quality of services that cleaners provide there. Giant mantas’ fidelity to this site may also be attributed to localised concentrations of food that are available nearby. The seamount provides habitat that appears to be important to the life history strategies of the region’s giant manta rays.
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Alpine ibex, Capra ibex, Linnaeus 1758In this chapter we review the current status of knowledge about Alpine ibex Capra ibex. We cover taxonomy, systematics, distribution, habitat, genetics, life history, behaviour, parasites and disease, population ecology and conservation. We conclude examining the future challenges for research and management of this species.
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An introduction to Phylogenetic Path AnalysisThe questions addressed by macroevolutionary biologists are often impervious to experimental approaches, and alternative methods have to be adopted. The phy- logenetic comparative approach is a very powerful one since it combines a large number of species and thus spans long periods of evolutionary change. However, there are limits to the inferences that can be drawn from the results, in part due to the limitations of the most commonly employed analytical methods. In this chapter, we show how confirmatory path analysis can be undertaken explicitly controlling for non-independence due to shared ancestry. The phylogenetic path analysis method we present allows researchers to move beyond the estimation of direct effects and analyze the relative importance of alternative causal models including direct and indirect paths of influence among variables. We begin the chapter with a general introduction to path analysis and then present a step-by-step guide to phylogenetic path analysis using the d-separation method. We also show how the known statistical problems associated with non-independence of data points due to shared ancestry become compounded in path analysis. We finish with a discussion about the potential effects of collinearity and measurement error, and a look toward possible future developments.
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Distribution, status and recent population dynamics of Alpine ibex Capra ibex in Europe1. Despite its recent successful and well-documented reintroduction history, a comprehensive and current update of the distribution and status of the Alpine ibex Capra ibex is lacking. As some concerns persist about its conservation, a status update appears essential for future conservation and management strategies on a large scale. 2. We provide an exhaustive update of the geographic range of the species, alongside estimates of its current abundance and population trends from 2004 to 2015. 3. We gathered census and distribution data for all the Alpine ibex colonies from management authorities and research groups that monitor them in different countries, and from the literature and publicly available reports. We produced a distribution map, reported the number of individuals observed in the most recent censuses, and estimated global, national, and local population trends using Bayesian hierarchical models. 4. Our model estimated that there were a total of 55297 Alpine ibex in the Alps in 2015 (lower 95% Credible Interval [CrI]: 51157; upper 95% CrI: 62710). The total number of individuals appears to have increased slightly over the last 10 years from the 47000-51000 estimated in previous reports. Positive population trends were observed in Switzerland and Italy, while no trend was apparent in France. For Austria, Germany, and Slovenia, there were insufficient data to estimate a trend. The slopes of the colonies’ trends were positively correlated with the year of colony foundation. 5. The geographic range of the Alpine ibex does not seem to have increased in size in recent years, although the accuracy of the spatial data varies among countries. 6. The periodic and standardised collection of census data for all colonies and a common policy of data-sharing at a European level appear essential for monitoring the global trend of this species and for planning balanced conservation and management actions.
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Improving the practicality of using non-aversive handling methods to reduce background stress and anxiety in laboratory miceHandling can stimulate stress and anxiety in laboratory animals that negatively impacts welfare and introduces a confounding factor in many areas of research. Picking up mice by the tail is a major source of handling stress that results in strong aversion to the handler, while mice familiarised with being picked up in a tunnel or cupped on the open hand show low stress and anxiety, and actively seek interaction with their handlers. Here we investigate the duration and frequency of handling required for effective familiarisation with these non-aversive handling methods, and test whether this is sufficient to prevent aversion and anxiety when animals then experience immobilisation and a mild procedure (subcutaneous injection). Very brief handling (2 s) was sufficient to familiarise mice with tunnel handling, even when experienced only during cage cleaning. Brief but more frequent handling was needed for familiarisation with cup handling, while pick up by tail induced strong aversion even when handling was brief and infrequent. Experience of repeated immobilisation and subcutaneous injection did not reverse the positive effects of tunnel handling. Our findings demonstrate that replacing tail with tunnel handling during routine cage cleaning and procedures provides a major refinement with little if any cost for familiarisation.
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Combining bioacoustics and occupancy modelling for improved monitoring of rare breeding bird populationsEffective monitoring of rare and declining species is critical to enable their conservation, but can often be difficult due to detectability or survey constraints. However, developments in acoustic recorders are enabling an important new approach for improved monitoring that is especially applicable for long-term studies, and for use in difficult environments or with cryptic species. Bioacoustic data may be effectively analysed within an occupancy modelling framework, as presence/absence can be determined, and repeated survey events can be accommodated. Hence, both occupancy and detectability estimates can be produced from large, coherent datasets. However, the most effective methods for the practical detection and identification of call data are still far from established. We assessed a novel combination of automated clustering and manual verification to detect and identify heathland bird vocalizations, covering a period of six days at 44 sampling locations Occupancy (Ψ) and detectability (p ) were modelled for each species, and the best fit models provided values of: nightjar Ψ=0.684, p=0.740, Dartford warbler Ψ=0.449 p=0.196 and woodlark Ψ=0.13 p=0.996. Including environmental covariates within the occupancy models indicated that tree, wetland and heather cover were important variables, particularly influencing detectability. The protocol used here allowed robust and consistent survey data to be gathered, with limited fieldwork resourcing, allowing population estimates to be generated for the target bird species. The combination of bioacoustics and occupancy modelling can provide a valuable new monitoring approach, allowing population trends to be identified, and the effects of environmental change and site management to be assessed.
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Mangrove and mudflat food webs are segregated across four trophic levels, yet connected by highly mobile top predatorsSeascape connectivity is crucial for healthy, resilient ecosystems and fisheries. Yet, our understanding of connectivity in turbid mangrove-lined estuaries—some of the world’s most productive ecosystems—is limited to macrotidal systems, and rarely incorporates highly mobile top predators. We analysed δ13C and δ15N isotope values of 7 primary producers, 24 invertebrate taxa, 13 fishes, 4 birds and 1 reptile to reveal trophic interactions within and between a mangrove and adjacent mudflat in a microtidal system of the Gulf of Paria, Orinoco River estuary. Primary producers, invertebrates and fishes collected within the mangrove were significantly depleted in 13C and 15N compared to those collected on the mudflat. Stable isotope mixing models showed that mangrove-derived carbon was predominantly assimilated by invertebrates (78 ± 5% SE) and fishes (88 ± 11%) sampled in the mangrove. In contrast, invertebrates and fishes sampled in the mudflat derived <21% of their carbon from mangrove sources. Instead, microphytobenthos and phytoplankton underpinned the mudflat food web. Scarlet ibis Eudocimus ruber and yellow-crowned night heron Nyctanassa violacea were also highly associated with mangrove carbon sources. However, osprey Pandion haliaetus, snowy egret Egretta thula and spectacled caiman Caiman crocodilus obtained carbon from both mangrove and mudflat sources, effectively integrating the food webs. The present study demonstrates simultaneous aspects of food web segregation and connectivity, as well as the importance of surveying the entire food web across a range of tidal systems when investigating seascape connectivity.
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Changes in selective biomarkers after transurethral resection of the bladder tumour (TURBT), and their association with Non-muscle invasive bladder cancer (NMIBC) recurrence and progressionIntroduction Bladder Cancer (BC) is the 10th most common cancer in the UK, with about 10,000 new cases annually. It affects more men than women (ratio 3:1). Major risk factors include tobacco, chemical carcinogens, schistosomiasis infection and age. About 75-85% of BC are non-muscle invasive (NMIBC), which is associated with high recurrence and progression rates (50-60% within 7-10 years). Currently, diagnosis, treatment and management of BC is via clinical procedures such as transurethral resection of the bladder tumour (TURBT) and endoscopy. Concerning laboratory investigations, there are no routine biomarkers currently available for identifying BC patients at increased risk of developing recurrence and progression. By monitoring changes in selective biomarkers post-TURBT, any sustained changes may be a predictor of cancer recurrence or progression. The main-focus of this research study was to evaluate changes in selective novel biomarkers and their association with recurrence and progression in BC. Materials & Methods In this research, 40 patients (n=40) scheduled for TURBT at the Wrexham Maelor Hospital, North Wales were recruited after written informed consent. Ethical approval for the project was granted via IRAS (REC4: 14/WA/0033). Venous blood samples were taken at baseline (pre-operative) and following TURBT surgery at 1, 3 and 6 months post-operatively. Bladder tumour samples were also taken during TURBT according to standard procedure. Selective biomarkers to assess inflammation, angiogenesis and tumour growth, were measured using commercially available ELISA and BioPlex multiplex assay kits. Tissue immunoreactivity of novel biomarkers were also assessed in BC tissues using immunohistochemistry, with clinical outcome measures being recorded for all patients. Results Significant increases in serum Cluster of differentiation 31 (CD31) (p=0.003) and Stem Cell Factor (SCF) (p=0.032) concentration, as well as trends of increasing concentration of serum basic Fibroblast Growth Factor (bFGF) (p=0.14), Vascular Endothelial Growth Factor Receptor-1 and 2 (VEGFR-1) (p=0.15), VEGFR-2 (p=0.15) and Follistatin (p=0.40) were observed in BC patients up to 6 months post-operative. There were also significant decreases in serum Macrophage Inflammatory Protein -2 (MIP-2) (p=0.001), Platelet Derived Growth Factor (PDGF) (p=0.012), Matrix Metalloproteinase-9 (MMP-9) (p=0.002) and Vascular Endothelial Growth Factor C (VEGF-C) (p=0.04) serum concentration. Trends of decreasing concentration in MMP-2 (p=0.79), MMP-3 (p=0.15), interleukin-6 (IL-6) (p=0.26), interleukin-8 (IL-8) (p=0.15) and tumour necrosis factor-α (TNF-α) (p=0.69) were observed in BC patients up to 6 months post-operative. There was significant immunoreactivity of CD31 (p< 0.001), CD34 (p< 0.001), Human epidermal growth factor receptor-2 (HER-2) (p=0.032), S100P (p< 0.001), Cyclooxygenase-2 (COX-2) (p< 0.001), VEGFR-3 (p< 0.001), SOX-2 (p< 0.001) and thrombomodulin (p=0.010) in bladder tumours. Although recurrence was significantly associated with cancer grade, there was no association with antibody immunoreactivity. Conclusion Findings from the present study may indicate an alternative approach in the monitoring and management of patients with BC. It is proposed that by allowing urological surgeons access to laboratory markers such as MIP-2, MMP-9, PDGF, SCF, HER-2, Thrombomodulin and CD31 (biomarker profile), potentially, in the future, these biomarkers may be used in addition to, or in combination with, currently used scoring systems to predict cancer recurrence and progression. However, verification and validation of these biomarkers are needed using larger cohorts.
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A novel method to optimise the utility of underused moulted plumulaceous feather samples for genetic analysis in bird conservation.Non-invasive sampling methods are increasingly being used in conservation research as they reduce or eliminate the stress and disturbance resulting from invasive sampling of blood or tissue. Here we present a protocol optimised for obtaining usable genetic material from moulted plumulaceous feather samples. The combination of simple alterations to a ‘user-developed’ method, comprised of increased incubation time and modification of temperature and volume of DNA elution buffer, are outlined to increase DNA yield and significantly increase DNA concentration (W = 81, p <0.01, Cohens’s d= 0.89). We also demonstrate that the use of a primerless Polymerase Chain Reaction (PCR) technique increases DNA quality and amplification success when used prior to PCR reactions targeting avian mitochondrial DNA (mtDNA). A small amplicon strategy proved effective for mtDNA amplification using PCR, targeting three overlapping 314-359bp regions of the cytochrome oxidase I barcoding region which, when combined, aligned with target-species reference sequences. We provide evidence that samples collected non-invasively in the field and kept in non-optimal conditions for DNA extraction can be used effectively to sequence a 650bp region of mtDNA for genetic analysis.
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Preparation of Primary Rat Hepatocyte Spheroids Utilizing the Liquid-Overlay Technique.Herein, we describe a protocol for the preparation and analysis of primary isolated rat hepatocytes in a 3D cell culture format described as spheroids. The hepatocyte cells spontaneously self-aggregate into spheroids without the need for synthetic extracellular matrices or hydrogels. Primary rat hepatocytes (PRHs) are a readily available source of primary differentiated liver cells and therefore conserve many of the required liver-specific functional markers, and elicit the natural in vivo phenotype when compared with common hepatic cells lines. We describe the liquid-overlay technique which provides an ultra-low attachment surface on which PRHs can be cultured as spheroids. © 2019 The Authors. Basic Protocol 1: Preparation of agarose-coated plates Basic Protocol 2: Primary rat hepatocyte isolation procedure Basic Protocol 3: Primary rat hepatocyte spheroid culture Basic Protocol 4: Immunofluorescent analysis of PRH spheroids. [Abstract copyright: © 2019 The Authors.]
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Individual, social, and environmental factors affecting salivary and fecal cortisol levels in captive pied tamarins (Saguinus bicolor)Pied tamarins (Saguinus bicolor) are endangered New World primates, and in captivity appear to be very susceptible to stress. We measured cortisol in 214 saliva samples from 36 tamarins and in 227 fecal samples from 27 tamarins, and investigated the effects of age, sex, pregnancy, rearing history, social status, weight, group composition, and enclosure type using generalized linear mixed models. There was no effect of age on either fecal or salivary cortisol levels. Female pied tamarins in late pregnancy had higher fecal cortisol levels than those in early pregnancy, or nonpregnant females, but there was no effect of pregnancy on salivary cortisol. Females had higher salivary cortisol levels than males, but there was no effect of rearing history. However, for fecal cortisol, there was an interaction between sex and rearing history. Hand‐reared tamarins overall had higher fecal cortisol levels, but while male parent‐reared tamarins had higher levels than females who were parent‐ reared, the reverse was true for hand‐reared individuals. There was a trend towards lower fecal cortisol levels in subordinate individuals, but no effect of status on salivary cortisol. Fecal but not salivary cortisol levels declined with increasing weight. We found little effect of group composition on cortisol levels in either saliva or feces, suggesting that as long as tamarins are housed socially, the nature of the group is of less importance. However, animals in off‐show enclosures had higher salivary and fecal cortisol levels than individuals housed on‐show. We suggest that large on‐show enclosures with permanent access to off‐exhibit areas may compensate for the effects of visitor disturbance, and a larger number of tamarins of the same species housed close together may explain the higher cortisol levels found in tamarins living in off‐show accommodation, but further research is needed.
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The importance of research applicabilityMarino & Merskin’s (2019) review contains key information about the complexity of sheep and their intelligence level, but lacks practical application. The key to making any long-term changes to sheep welfare at an industry level is by generating research that is practically relevant to the sector. The practical application of research should be considered at the design stage and in consultation with producers. Additionally, thought needs to be given to how the practical application of the research will be transferred to those people directly involved in animal care (e.g. producers, stockpersons, etc.). Focusing on the practical relevance and application of research at all stages of the process will foster changes to long-held beliefs and attitudes.
