Non-lethal Methods Research Articles

Molecular biomarkers for sperm quality in an economically important fish: Blue catfish, Ictalurus furcatus

Intraspecies variability in sperm quality is common among aquaculture species, thus necessitating an urgent need to establish reliable molecular biomarkers to screen for males with high-quality sperm. The channel catfish (Ictalurus punctatus) ♀ × blue catfish (I. furcatus) ♂ hybrid accounts for >50% of United States catfish production. Blue catfish sperm cannot be collected using non-lethal methods, and thus, males must be sacrificed to determine reproductive quality. To establish gene expression biomarkers of sperm quality, we characterized important sperm traits, ranked blue catfish males based on the curvilinear velocity of their sperm, and sequenced testicular tissue for mRNAs and sRNAs. Of the 43 males characterized, testicular tissue from 4 individuals with low-velocity (155.70 mm/s ± 1.49 SD) and 4 with high-velocity (205.01 mm/s ± 4.63 SD) were chosen for sequencing. No differentially expressed sRNAs were detected between the two sperm performance groups. However, we identified two differentially expressed mRNA transcripts between the low-velocity and high-velocity groups, aqp3a and ly97.3, both upregulated in the high-velocity group compared to the low-velocity group. These molecular biomarkers of sperm quality in testicular tissue are linked to gamete quality and may be applied for more efficient catfish aquaculture.

Capture Response and Long-Term Fate of White Sharks (Carcharodon carcharias) after Release from SMART Drumlines.

Human-shark conflict has been managed through catch-and-kill policies in most parts of the world. More recently, there has been a greater demand for shark bite mitigation measures to improve protection for water users whilst minimizing harm to non-target and target species, particularly White Sharks (Carcharodon carcharias), given their status as a Threatened, Endangered, or Protected (TEP) species. A new non-lethal shark bite mitigation method, known as the Shark-Management-Alert-in-Real-Time (SMART) drumline, alerts responders when an animal takes the bait and thereby provides an opportunity for rapid response to the catch and potentially to relocate, tag, and release sharks. Thirty-six White Sharks were caught on SMART drumlines in New South Wales, Australia, and tagged with dorsal fin-mounted satellite-linked radio transmitters (SLRTs) and acoustic tags before release. Thirty-one sharks were located within 10 days, 22 of which provided high-quality locations (classes 1 to 3) suitable for analysis. Twenty-seven percent and 59% of these sharks were first detected within 10 and 50 h of release, respectively. For the first three days post-release, sharks moved and mostly remained offshore (>3.5 km from the coast), irrespective of shark sex and length. Thereafter, tagged sharks progressively moved inshore; however, 77% remained more than 1.9 km off the coast and an average of 5 km away from the tagging location, 10 days post-release. Sharks were acoustically detected for an average of 591 days post-release (ranging from 45 to 1075 days). Although five of the 36 sharks were not detected on acoustic receivers, SLRT detections for these five sharks ranged between 43 and 639 days post-release, indicating zero mortality associated with capture. These results highlight the suitability of SMART drumlines as a potential non-lethal shark bite mitigation tool for TEP species such as White Sharks, as they initially move away from the capture site, and thereby this bather protection tool diminishes the immediate risk of shark interactions at that site.

Evaluation of meso- and microplastic ingestion by the northern fulmar through a non-lethal sampling method

An increasing number of organisms from the polar regions are reported contaminated by plastic. Rarely a non-killing sampling method is used. In this study we wanted to assess plastic levels using stomach flushing and evaluate the method suitability for further research and monitoring. The stomach of 22 fulmars from Bjørnøya, Svalbard, were flushed with water in the field. On return to the laboratory, the regurgitated content was digested using potassium hydroxide. The extracted plastics were visually characterised and analysed with spectroscopy. Only three birds had plastics in their stomach, totaling 36 particles, most of them microplastics (< 5 mm). The plastic burdens are much lower than previously reported in Svalbard. The stomach flushing is assumed not to allow the collection of the gizzard content. This is a major limitation as most of the plastics accumulate in the fulmar's gizzard. However, the method is still useful for studies investigating plastic ingestion dynamics, allowing to sample the same individuals over time.

Combining two non-lethal methods in crossover design randomized experiments.

Abstract Wildlife control is the subfield pertaining to preventing threats to human property or safety from wild animals. Various research fields interact within wildlife control from animal behavior to agricultural management and other social sciences. We review understanding of the effectiveness of interventions using nighttime lights and fladry, both visual deterrents, to prevent carnivores from approaching livestock on working farms. We describe successes and failures in randomized. Controlled trials (RCT) with crossover design and the limits to inference and generalizability of their results. We present quantitative and qualitative evidence -- from two unpublished RCTs with crossover designs -- as a heuristic device to organize knowledge and highlight associated gaps. We focus on the sustainability of scientific wildlife control and collaborative research with farmers, material interventions, wildlife coexistence with livestock and people, and science communication. We conclude that small-scale field experiments will rarely achieve the statistical power to confidently generalize recommendations to use or avoid tested methods. Therefore, cautious experimental scientists who wish to avoid false discoveries or exaggerated claims may routinely experience constraints on promoting methods for wildlife control. The same constraints may not be felt by farmers or their allies, creating a tension in the science-policy interface between personal testimonials and scientific generalizations. We recommend steps that may fortify the science and enhance the sustainability of robust experimental designs under field conditions.

Assessing the validity of fecal sampling for characterizing variation in threespine stickleback's gut microbiota.

The gut microbiota is crucial for many aspects of their hosts' biology, and it has been characterized for many species across the animal kingdom. Yet, we still don't have a good understanding of whether non-lethal sampling can accurately capture the diversity of gut-associated bacterial communities, as estimated from lethal sampling of intestinal tissue. We further lack knowledge on whether non-lethal sampling methods are suitable for detecting gut microbiota shifts associated with changes in environmental factors (e.g., diet). We addressed these questions in threespine stickleback fish, a model system for evolutionary ecology, by comparing bacterial communities from intestinal tissue and feces. Despite some differences in community composition between the two sample types and considerable temporal variation among fecal samples, bacterial communities appear to largely overlap. Further, we detected consistent and significant changes of fecal bacterial communities associated with an experimental diet manipulation. This suggests that fecal sampling can represent an adequate non-lethal method to characterize the gut microbiota of threespine stickleback, but additional studies will be necessary before drawing general conclusions regarding the validity of fecal sampling for gut microbiota studies. To this end, we give recommendations to improve the characterization of the gut microbiota via fecal sampling. Fecal sampling allows studying temporal gut microbiota shifts associated with environmental change at the individual level, which increases opportunities for future experimental gut microbiota research.

The Use and Prospects of Nonlethal Methods in Entomology.

Arthropods are declining globally, and entomologists ought to be in the forefront of protecting them. However, entomological study methods are typically lethal, and we argue that this makes the ethical status of the profession precarious. Lethal methods are used in most studies, even those that aim to support arthropod conservation. Additionally, almost all collecting methods result in bycatch, and a first step toward less destructive research practices is to minimize bycatch and/or ensure its proper storage and use. In this review, we describe the available suite of nonlethal methods with the aim of promoting their use. We classify nonlethal methods into (a) reuse of already collected material, (b) methods that are damaging but not lethal, (c) methods that modify behavior, and (d) true nonlethal methods. Artificial intelligence and miniaturization will help to extend the nonlethal methodological toolkit, but the need for further method development and testing remains.

Evaluating blood, gill, and muscle biopsy methods on the behaviour, reproductive success, and survival of a wild freshwater fish

Non-lethal biopsy methods (including blood, gill, and muscle biopsies) have been used to study the health and physiological status of wild fishes. Nonetheless, concerns exist regarding the impact of non-lethal sampling on relevant welfare measures such as behaviour and survival. Here, nesting Smallmouth Bass (Micropterus dolomieu) were used as a model species to study in situ how fish respond to non-lethal sampling. Male Smallmouth Bass provide sole parental care and guard well-defined nests for a period of several weeks, providing a unique opportunity to assess behaviour, reproductive success, and survival in the wild. Fish were captured from their nests by angling and subjected to a biopsy (either blood, gill, or muscle), or a combination of all three biopsy methods prior to release. A control group that was captured but not biopsied as well as a non-angled control were also included. Nests were monitored for a period of four weeks or until the parental males either abandoned offspring, died, or raised a brood to independence. Single biopsies, regardless of the biopsy type, were found to have no impact on parental care and survival, but fish that received the combined treatment took longer to return to their nest and displayed a 6.5 times greater likelihood of nest abandonment. Mortality was only observed in fish that received the combined biopsy treatment. As such, this study reveals that it is possible to maintain the welfare status of Smallmouth Bass in the wild by using individual biopsies, thus emphasizing the importance of making careful decisions about which tissues are needed to achieve desired study objectives. This is one of the few studies to assess the behavioural and fitness consequences of increasingly common non-lethal biopsy methods and provides useful information on the relative consequences of different biopsy methods on wild fish.

Transcriptomic and targeted immune transcript analyses confirm localized skin immune responses in Atlantic salmon towards the salmon louse.

Atlantic salmon (Salmo salar) are highly susceptible to infestations with the ectoparasite Lepeophtheirus salmonis, the salmon louse. Infestations elicit an immune response in the fish, but the response does not lead to parasite clearance, nor does it protect against subsequent infestations. It is, however, not known why the immune response is not adequate, possibly because the local response directly underneath the louse has been poorly evaluated. The present study describes the transcriptomic response by RNA sequencing of skin at the site of copepodid attachment. Analysing differentially expressed genes, 2864 were higher and 1357 were lower expressed at the louse attachment site compared to uninfested sites in the louse infested fish, while gene expression at uninfested sites were similar to uninfested control fish. The transcriptional patterns of selected immune genes were further detailed in three skin compartments/types: Whole skin, scales only and fin tissue. The elevation of pro-inflammatory cytokines and immune cell marker transcripts observed in whole skin and scale samples were not induced in fin, and a higher cytokine transcript level in scale samples suggest it can be used as a nonlethal sampling method to enhance selective breeding trials. Furthermore, the immune response was followed in both skin and anterior kidney as the infestation developed. Here, newly moulted preadult 1 stage lice induced a higher immune response than chalimi and adult lice. Overall, infestation with salmon louse induce a modest but early immune response with an elevation of mainly innate immune transcripts, with the response primarily localized to the site of attachment.

Metal Contaminants in Fish: Blood as a Potential Non-lethal Monitoring Tool.

The use of fish to monitor metal contamination is well established, but existing studies often focus on internal tissues that require the sacrifice of organisms. Developing non-lethal methods is thus a scientific challenge to enable large scale biomonitoring of wildlife health. We explored blood as a potential non-lethal monitoring tool for metal contamination in brown trout (Salmo trutta fario) as a model species. First, we investigated differences in metal contamination loads (i.e., Cr, Cu, Se, Zn, As, Cd, Pb and Sb) in different blood components (whole blood, red blood cells and plasma). Whole blood was reliable to measure most metals, implying that blood centrifugation is not necessary, thus minimizing sample preparation time. Second, we measured the within individual distribution of metals across tissues (whole blood, muscle, liver, bile, kidney and gonads) to test if blood could be a reliable monitoring tool compared to other tissues. Results show that the whole blood was reliable compared to muscle and bile to measure the levels of metals such as Cr, Cu, Se, Zn, Cd and Pb. This study opens the possibility for future ecotoxicological studies in fish to use blood instead of internal tissues to quantify some metals, thus reducing the negative impacts of biomonitoring on wildlife.

Small-livestock farmers’ perceived effectiveness of predation control methods and the correlates of reported illegal poison use in the South African Karoo

The use of poison against predators is pervasive and negatively impacts biodiversity and ecosystem health globally. Little is known about the correlates of poison use as a lethal control method on small-livestock farmland. We used a mixed-methods approach to investigate commercial farmers’ experience with and perceived effectiveness of predation control methods, reported poison use and its correlates in the Central Karoo. Farmers perceived lethal methods to be cheaper and more effective than non-lethal methods in protecting their livestock from predation. They reported more experience with lethal methods, and over half reported having used poison. This is higher than other estimates in southern Africa and consistent with other survey-based evidence from the Karoo. Reported poison use was positively related to perceived efficacy, declining on-farm employment and perceived threats of predators. It was negatively related to terrain ruggedness. Our findings provide an understanding of the context and motivations shaping this illegal behavior.

Promoting the use of non-lethal sample collection for analysing the trophic relationships of inshore flatfish populations using stable isotope analysis

Trophic studies on inshore flatfish populations usually rely on stomach content analyses and/or stable isotope analysis (SIA) of dorsal white muscle that involves the collection of samples from euthanised fishes. To promote the use of non-lethal sampling methods in inshore flatfish populations of relatively high intrinsic angling and/or ecological value, the applicability of using fin tissue and/or epidermal mucus as non-lethal alternatives to muscle in SIA studies was assessed for European flounder Platichthys flesus, plaice Pleuronectes platessa and common sole Solea solea. In all species, the results indicated that there were significant differences in the δ13C and δ15N values of dorsal muscle versus their fin and mucus samples. These significant differences were, however, predictable by linear regression, with regression coefficients produced for converting fin and mucus SI values to the equivalent muscle SI values. The use of combined data across the species also provided regression coefficients for converting fin and mucus SI to equivalent muscle values for flatfish populations more generally. These results indicated that there are tissue alternatives to dorsal muscle that can be applied to the SIA of flatfish populations, with these tissues able to be collected using non-lethal sampling methods.

Local variability, human factor or vague procedure? Searching for the reasons of excessive mortality in free living aquatic insects, resulting from biological monitoring

During the analysis of the biomonitoring data of Polish watercourses, it was found that the vast majority of aquatic insects (83–95% of more than 8.8 million individuals collected between 2012 and 2019) die unnecessarily during sampling, as a result of the sub-sampling procedure. Great, in some cases 30-fold differences in the mortality of insects, including those belonging to protected taxa, were observed between the samples analyzed by various regional laboratories. The most important reason for these differences appears to be factors that can be collectively referred to as the ‘human factor’, related to removing insects from the sphere of ethical protection, makes their killing an activity ethically neutral. This kind of attitude, which does not attach any importance to the life and suffering of insects interacts with the lack of precise requirements for the sampling equipment used. Those factors seem to be the most important in explaining the causes of excessive mortality of aquatic insects during sampling and the huge differences between laboratories. Principal component analysis and the analysis of variability measures showed that ecological differences between sampling sites can only be considered as a secondary determinant.Implications for insect conservationImproperly planned and conducted monitoring procedures, through excessive mortality of free-living aquatic insects, have or may have a negative impact on the environment and biodiversity. Therefore, it seems very important to promote alternative solutions that reduce such mortality in biological monitoring, such as: non-lethal methods of animal sampling, the use of pre-sampling areas to estimate the density of animals before sampling and estimation of the maximum abundance of a sample necessary for a reliable estimate of taxonomic richness using rarefaction.

The Role of Veterinarians in Managing Community Cats: A Contextualized, Comprehensive Approach for Biodiversity, Public Health, and Animal Welfare.

Homeless cats are a major problem in Europe, with hundreds of thousands abandoned every year. While many die, others can adapt to a lifestyle of roaming freely and establish community cat populations that tend to cluster together in groups. These groups of cats are typically found in urban areas that offer food and shelter to the cats. Animal welfare organizations often care for these cats, providing them with food, shelter, and medical attention. Despite this, conflicts can arise due to the presence of free-roaming cats, with some individuals advocating for drastic measures such as trapping and killing the cats to reduce their populations. However, it is essential to note that such methods are frequently illegal, inhumane, and ultimately ineffective in most situations. A thorough assessment of the impact of cats on a particular natural area requires a comprehensive cat census, a detailed study of the species being preyed upon, and an investigation into the prevalence of zoonotic or epizootic diseases. Moreover, veterinary experts assert that the public health risks associated with cats are often overstated. This article aims to provide a nuanced perspective on the impact of cats on biodiversity in natural areas, while also discussing their role in transmitting the main zoonotic diseases identified in European countries in recent years, with a particular focus on Spain. Effective cat control programs should focus on non-lethal methods such as trap-neuter-return (TNR) and adoption. TNR has proven to be the most effective and humane method of controlling the free-roaming cat population, but its effectiveness is influenced by several factors, including adoption programs and public education on responsible pet ownership. According to Spanish veterinarians, sustainable and science-based solutions such as TNR programs are the best way to achieve population control of free-roaming cats. The veterinary profession should raise awareness regarding sterilization, vaccination, and identification of cats and the consequences of abandonment. They oppose lethal control and removal of cats from the environment, which are ineffective and unethical methods. To promote animal welfare, veterinary professionals must collaborate with public administrations to implement long-term, sustainable solutions to the problem of cat overpopulation. Greater social awareness regarding the importance of sterilization and identification to prevent abandonment and reduce the number of free-roaming cats is also needed. Despite the challenges presented by homeless cat populations in Spain and the rest of Europe, there are many reasons for optimism. Animal welfare organizations and veterinary professionals are actively collaborating to develop humane and effective solutions to manage community cats, including programs such as TNR and adoption. Furthermore, these initiatives are gaining momentum and support from emerging laws and regulations, such as the recent Spanish animal welfare law. Through these efforts, we can reduce the number of free-roaming cats and improve their quality of life.

Self-inflicted Stabbings as Nonfatal Suicide Attempts: A Systematic Review and Case Series.

Suicide by cutting or piercing is a rare and often nonlethal method. Self-stabbings are a subset of these cases, which can lead to significant injuries. Current literature does not adequately summarize the psychiatric characteristics of this population. To examine the psychiatric presentations of adults with nonfatal self-inflicted stabbing suicide attempts to better inform the evidence-based care provided by the psychiatric consult service. We searched Embase, Ovid MEDLINE, APA Psych INFO, and CINAHL for studies published within the last 15 years. All full-article case reports, case series, cohort studies, and systematic literature reviews in English were included. Studies not specific to adult (only those >18 years old were included) patients with self-inflicted stabbing wounds were excluded. Included studies were separated into 2 groups: case reports and cohort studies. Simple summative statistical analyses were performed. The quality of evidence was assessed using a modified version of the Joanna Briggs Institute Critical Appraisal Tools. Thirty-four case reports, 3 cohort studies, and zero systematic literature reviews met the inclusion and quality assessment criteria. A total of 184 cases of self-stabbing were identified, 66% of which included male patients. The mean age of cohort patients was 44 years. The mean age of case report patients was 47 years. The most common tool for stabbing was a knife. Common stabbing locations included the neck, chest, and abdomen. Commonly reported psychiatric diagnoses included mood disorders and schizophrenia spectrum disorders. Self-stabbing characteristics important to psychiatry were inconsistently reported across studies. This literature review found that self-stabbing appears to be a male-preferred method and may be associated with mood disorders. Inconsistent reporting of relevant psychiatric data such as psychiatric diagnosis, previous psychiatric history, suicidal intent, and intoxication is present in our review and is potentially due to a lack of reports from the psychiatric perspective. This limits our understanding of psychiatric issues in adults who made nonfatal self-inflicted stabbing suicide attempts. A further study into the presentations of this population is needed to better understand this distinct group of patients.

The need for a (non-destructive) method revolution in entomology

There are worrying signs that arthropods are in decline both in density and diversity. This threatens global biodiversity as well as the ecosystem services provided by arthropods. Nonetheless, entomological research, even when studying arthropods with a conservation focus, frequently uses lethal methods. We analysed 1029 articles published in the major biological conservation journals between 2014 and 2020 and found that, while single-species-focused studies used more non-lethal than lethal methods (76.3 % vs. 23.7 %, respectively), the opposite was true for multiple-species ones (24.0 % vs. 76.0 %). In tropical regions, 74.6 % of studies used lethal methods vs. 18.5 % non-lethal ones. Of the major orders, Odonata, Lepidoptera and Orthoptera were generally studied using non-lethal methods (88.1 %, 80.7 %, and 70.8 %, respectively) in non-tropical regions, while in the tropics, only Lepidoptera were frequently (51.9 %) studied by such methods. We argue that even if the evidence for arthropod decline were uncertain, and even if research would not add much to the overall level of mortality, entomologists should be showing an example. If research on invertebrates continues to be ethically blind, entomologists risk losing public support for conserving arthropod diversity.

Shell drilling and gonad biopsies provide a rapid, nonlethal method for in situ assessment of reproductive periodicity in a turbinid gastropod

ABSTRACT Reproductive data on marine molluscs are imperative for informing conservation and management strategies. Most methods for assessing reproductive periodicity are lethal, which could be unfavourable for fragile populations. This study aimed to trial a nonlethal, drill-biopsy technique for assessing the reproductive cycle in the turbinid gastropod, Turbo militaris. This technique was tested in the laboratory, where a small hole was drilled into the shell, from where a biopsy of the gonad was taken. The procedures resulted in zero mortalities and rapid recovery of the animals when returned to seawater. Sex was identified by viewing the gonad colour through the shell hole and confirmed by viewing gametes from a biopsy. Preservation of the female biopsy was investigated, with buffered formalin found to be the most suitable solution. The drill-biopsy method was also tested in the field; five (out of six) recaptured T. militaris had repaired the shell hole after 6 weeks, and two were recaptured on multiple occasions up to the end of this study, 10 months later. The size–frequency distributions of oocytes from female biopsies suggested an increase in mode size over 2 months with a shift towards a higher number of larger oocytes, supporting the practicality of this nonlethal approach to evaluate reproductive periodicity and sex determination. Nonlethal sampling is recommended for broad-scale studies and populations under stress; methods, such as the drill-biopsy technique, facilitate reproductive sampling without detriment to the target populations.

Comparative analysis of two nonlethal methods for the study of the gut bacterial communities in wild lizards.

Fecal samples or cloacal swabs are preferred over lethal dissections to study vertebrate gut microbiota for ethical reasons, but it remains unclear which nonlethal methods provide more accurate information about gut microbiota. We compared the bacterial communities of three gastrointestinal tract (GIT) segments, that is, stomach, small intestine (midgut), and rectum (hindgut) with the bacterial communities of the cloaca and feces in the mesquite lizard Sceloporus grammicus. The hindgut had the highest taxonomic and functional alpha diversity, followed by midgut and feces, whereas the stomach and cloaca showed the lowest diversities. The taxonomic assemblages of the GIT segments at the phylum level were strongly correlated with those retrieved from feces and cloacal swabs (rs > 0.84 in all cases). The turnover ratio of Amplicon Sequence Variants (ASVs) between midgut and hindgut and the feces was lower than the ratio between these segments and the cloaca. More than half of the core-ASVs in the midgut (24 of 32) and hindgut (58 of 97) were also found in feces, while less than 5 were found in the cloaca. At the ASVs level, however, the structure of the bacterial communities of the midgut and hindgut were similar to those detected in feces and cloaca. Our findings suggest that fecal samples and cloacal swabs of spiny lizards provide a good approximation of the taxonomic assemblages and beta diversity of midgut and hindgut microbiota, while feces better represent the bacterial communities of the intestinal segments at a single nucleotide variation level than cloacal swabs.

Minimally Invasive Collection of Biometric Data Including Maturation Stage on European Eel Using Photography

AbstractIn response to the severe decline of the European Eel Anguilla anguilla stock in recent decades, various data frameworks and research efforts toward improved management rely on the availability of site‐specific biometric data. At the same time, scientists are obligated to minimize the negative effects (stress, harm, and sacrifice) of their samplings on individuals and the population without compromising data quality. In‐field methods for biometric measurements must be quick, precise, and practical for the user. Essential information that is typically required in (large‐scale) eel monitoring programs includes body length, mass, sex, and maturation stage. As live eels are difficult to handle, individuals are typically anesthetized or killed (and sometimes stored frozen to postpone measurements) to obtain the necessary biometrics. The primary purpose of this paper was to explore the suitability of a nonlethal method based on photography for obtaining essential biometrics and maturation stage from live European Eels A. anguilla in a timely manner. In addition, we evaluated the relative accuracy of measuring the parameters that are necessary for assessing maturation stages in eels after defrosting and examined the necessity of correcting for potential shrinkage of eyes and pectoral fin. Both procedures were compared against a standard reference of measurements from freshly killed eels. We found that the minimally invasive method using alive measurements of eels' body length and mass together with digital measurements of eyes and pectoral fin from photographs had the highest agreement for maturation stage outcome with the fresh reference. Our results further reveal the necessity of correcting for shrinkage of eyes and pectoral fins (in addition to length and mass) after freezing to maximize reliability in stage classification. Consequently, we provide specialized formulae to apply shrinkage corrections for eye diameter and pectoral fin length.

Indexing hematological and serum biochemical reference intervals of Himalayan snow trout, Schizothorax esocinus to instrument in health assessment.

Schizothorax esocinus, commonly known as snow trout, is one of the main contributors of food and livelihood in the colder zone of Himalayan region. The comprehensive information on its hematological and serum biochemical reference intervals is not reported yet. In the present study an attempt has been made to elucidate the hematological and serum biochemical reference intervals of S. esocinus from River Jhelum using protocols of the American Society of Veterinary Clinical Pathology (ASVCP). Wild fish were sampled over a period of 2years from the pollution free sites of river Jhelum. Fish blood was harvested through caudal venipuncture and hemato-biochemical analysis performed thereof. Data values from a total of healthy 432 adult fish specimens (216 male, 216 female) were systematically recorded. The reference intervals for hematological and serum biochemical parameters of S. esocinus were established using Reference Value Advisor software v 2.1. RIs for hematological and serum analytes ranged as: hemoglobin (Hb) 78.38-116.35 (g/L); white blood cells (WBC) 10-20 (×109/L); red blood cells (RBC) 1.30-2.15 (×1012/L); packed cell volume 27.00-39.45 (%); total protein 39.21-61.62 (g/L); albumin 8.20-22.02 (g/L); globulin 27.58-49.55 (g/L); glucose 3.25-7.18 (mmol/L); urea 0.96-2.38 (mmol/L); cholesterol 3.80-6.90 (mmol/L). The study also depicted that certain blood measurands were influenced with respect to sex. Significantly (p < 0.05) higher values of Hb, red blood cells count and serum glucose were noted in male as compared to female which, on the other hand, registered higher white blood cells count and serum cholesterol level (Mann Whitney U test, p < 0.05). The work, therefore, provides baseline information on hematological and serum biochemical analytes of this species which holds high commercial importance. RIs reported here can help monitor the health status of fish by improving the use of non-lethal diagnostic methods in piscine medicine.

Forest Fragmentation and Developmental Stability of Wood Mice Apodemus sylvaticus: A Food-Mediated Effect?

Generalist mice are key species for the long-term dynamics of fragmented forests due to their dual role as seed dispersers or predators of the dominant trees. Wood mice, Apodemus sylvaticus, usually act as a net predator in woodlots due to higher winter densities and earlier winter reproduction than in forests. Here we analyze the recruitment expectations of young mice born in woodlots in relation to food availability through an index of developmental stability that combined values of fluctuating asymmetry (FA) for six traits of the lower mandibles. FA was measured in young and adult mice caught at the end of the winter in control woodlots, food-supplemented woodlots and in a nearby large forest. Despite low sample sizes (n = 9 for young and n = 74 for adults), FA in young mice born in control woodlots were significantly higher than in those from food-supplemented woodlots and the forest and in all adults. Food limitation in woodlots was thus associated with increased developmental instability of young mice, but it had no effect on adults. Instability likely reduced the survival prospects of young mice through increased mortality, and this should be compensated by yearly recolonization of woodlots by adults from the agricultural matrix in autumn and winter. Future work analyzing mechanisms suggested here but using non-lethal methods will be important to clarify the impacts of FA on the population dynamics of wood mice.