Animal Size Research Articles

Long‐Term Mobility of a Harvested, Rocky‐Reef Gastropod

ABSTRACTStocks of Turbo militaris (Turbinidae) are under increasing harvesting pressure, but management is currently hampered by data deficiency. Management decisions for rocky‐reef gastropod fisheries should consider long‐term species mobility, yet this is often poorly understood. Therefore, mark‐recapture was used to evaluate annual displacement and upshore‐to‐downshore movement of T. militaris in Eastern Australia. Tags were glued onto 676 snails, their positions georeferenced and recapture surveys were conducted after 6 and 12 months. Overall, 25% of tagged snails were recaptured. Snails moved an average of 20–21 m year−1 at subtropical sites and 34–44 m year−1 at temperate sites. Movement was non‐directional, limited in upshore‐to‐downshore mixing and unrelated to animal size. T. militaris is neither sedentary nor site‐attached, and small and large snails move similarly. Our findings suggest a limited capacity for adults to repopulate other tidal zones, thus recreational harvesting could impact intertidal snails.

Biochemical Parameters of Laboratory Animals in Iraq: A Meta-analysis Study

Our objective in this work was to estimate normal values of biochemical parameters in laboratory animals in Iraq. Values were pooled from studies conducted in Iraqi universities using a meta-analysis approach. Pertinent peer-reviewed published studies were retrieved from the Iraqi Academic Scientific Journals (IASJ) database. Random-effects inverse-variance model was used to obtain pooled means of the parameters from the set of studies qualified for the analysis. Among a total of 460 records identified from IASJ, 264 records were eligible for the statistical analysis, which reported 102 values for different biochemical parameters. The mean of the sample size for normal animals that was used in the studies including in the analysis were 8, 8, and 6 for rats, mice, and rabbits respectively. The mean ± standard deviation of ages (months) was 2.8 ± 1.0, 3.14 ± 1.15, and 9.2 ± 3.3 for rats, mice, and rabbits respectively. In this analysis, we estimated 31, 14, and 15 parameters from 121, 41, and 26 studies of rats, mice, and rabbits correspondingly. The proportion of variance in the parameters for the analyzed studies due to heterogeneity was significant. Evidence of bias in the estimated values due to small studies was found in some parameters. In conclusion, we encourage researchers to consider the values we provided in this analysis and report details of the sample size, number of animals in each group, sex, exact age, and the accurate units for the estimated values in their studies to facilitate further analyses for more reference values in further analyses‎‎‎.

Biochemical Parameters of Laboratory Animals in Iraq: A Meta-analysis Study

Our objective in this work was to estimate normal values of biochemical parameters in laboratory animals in Iraq. Values were pooled from studies conducted in Iraqi universities using a meta-analysis approach. Pertinent peer-reviewed published studies were retrieved from the Iraqi Academic Scientific Journals (IASJ) database. Random-effects inverse-variance model was used to obtain pooled means of the parameters from the set of studies qualified for the analysis. Among a total of 460 records identified from IASJ, 264 records were eligible for the statistical analysis, which reported 102 values for different biochemical parameters. The mean of the sample size for normal animals that was used in the studies including in the analysis were 8, 8, and 6 for rats, mice, and rabbits respectively. The mean ± standard deviation of ages (months) was 2.8 ± 1.0, 3.14 ± 1.15, and 9.2 ± 3.3 for rats, mice, and rabbits respectively. In this analysis, we estimated 31, 14, and 15 parameters from 121, 41, and 26 studies of rats, mice, and rabbits correspondingly. The proportion of variance in the parameters for the analyzed studies due to heterogeneity was significant. Evidence of bias in the estimated values due to small studies was found in some parameters. In conclusion, we encourage researchers to consider the values we provided in this analysis and report details of the sample size, number of animals in each group, sex, exact age, and the accurate units for the estimated values in their studies to facilitate further analyses for more reference values in further analyses‎‎‎.

First report of Contagious caprine pleuropneumonia (CCPP) in Bangladeshi Goats: Seroprevalence, Risk factors and Molecular detection from Lung samples

Background and objectiveContagious caprine pleuropneumonia (CCPP) is a highly contagious mycoplasmal respiratory disease primarily affecting goats and sheep caused by Mycoplasma capricolum subsp. capripneumoniae (Mccp). So far, there is no available information on either the serological or molecular identification of Mccp in Bangladesh. Hence, the objective of this study was to determine the seroprevalence of CCPP and associated risk factors in goats of Bangladesh, as well as molecular identification of the causative agent (Mccp) in this country. Materials and MethodsFrom July 2022 to June 2023, 402 goat serum samples were randomly collected to determine seroprevalence, and 90 clinically suspected lung samples were collected for molecular confirmation of CCPP. Risk factors were evaluated by interviewing goat owners using a predesigned questionnaire. A commercially available cELISA kit was used to screen blood serum for anti-CCPP antibodies and PCR for Mccp detection. The 16S rRNA gene specific to Mycoplasma mycoides cluster (Mmc), and the Mccp-specific gene of Mycoplasma capricolum subsp. capripneumoniae (Mccp) were amplified through PCR. Potential risk factors were identified through a univariate logistic regression followed by a multivariate logistic regression model. ResultsOut of 402 samples, 29 were tested positive for CCPP, indicating an overall seroprevalence of 7.21% (95% CI: 1.90-12.53). The PCR result showed that 26.67% of the samples were positive for CCPP. The associated risk factors for the disease were animal age (>18 months; OR: 2.14, 95% CI: 0.92-4.98), sex (Female; OR: 5.80, 95% CI: 1.70-19.69), flock size (Large; OR: 6.28, 95% CI: 1.17-35.74), and body condition scores (Poor; OR: 5.58, 95% CI: 1.36-22.92). ConclusionThis study confirms the existence of CCPP in Bangladeshi goats for the first time using both serological and molecular methods (PCR).

Enhanced Yolov8 network with Extended Kalman Filter for wildlife detection and tracking in complex environments

Amid a growing global focus on ecological conservation and biodiversity monitoring, the efficient identification and tracking of wildlife are essential for environmental research, wildlife protection, and habitat management. Nevertheless, intricate landscapes, varied animal sizes, and obstructions obstruct wildlife detection and tracking. This study introduces the wilDT-YOLOv8n model, specifically engineered for the effective identification and tracking of animals. Initially, the Stable Diffusion model augments the dataset, establishing a basis for training data. Subsequently, enhancements to the Yolov8n model are implemented through the incorporation of the deformable convolutional network DCNv3 and the utilization of the C2f_DCNV3 layer to augment feature extraction efficacy, while addressing detection challenges associated with small targets and intricate backgrounds by integrating the EMGA attention mechanism and the ASPFC feature fusion module. Enhancing the Extended Kalman Filter algorithm guarantees reliable and precise tracking. The research findings reveal that the wilDT-YOLOv8n model attained an average detection accuracy (mAP50) of 88.54 % on the custom dataset, reflecting a 4.57 % enhancement over the original YOLOv8n model; the refined Extended Kalman Filter realizes a Multi-Object Tracking Accuracy (MOTA) of 40.35 %, representing a 3.923 % advancement over the original Kalman Filter. The results indicate the feasibility of accurately detecting and monitoring wildlife in intricate environments, offering significant insights for ecological research and biodiversity conservation, and aiding in the protection of endangered species.

Deep learning applied to the segmentation of rodent brain MRI data outperforms noisy ground truth on full-fledged brain atlases

Translational magnetic resonance imaging of the rodent brain provides invaluable information for preclinical drug development. However, the automated segmentation of such images for quantitative analyses is limited compared to human brain imaging mainly due to the inferior anatomical contrast and the resulting less advanced registration and atlasing tools. Here, we investigated the potential of deep learning models for the segmentation of magnetic resonance images of rat brains into an entire set of multiple regions of interest (rather than individual loci), focusing on the development of a robust method that accommodates changes in the input based on differences in animal strain (genotype) and size. Manually generated labels are expensive, so we tested the ability of neural networks to learn brain structures from noisy but inexpensive registration-based labels, allowing very large datasets to be leveraged for training. We compared three distinct model architectures (U-Net, Attention-U-Net and DeepLab) by training them on a dataset of >10,000 magnetic resonance images of rat brains and found that each model was able to segment the entire brain into predefined sets of 29 and 58 regions, respectively, with the Attention U-Net achieving the best performance. The models canceled out unstructured label noise in the imperfect training data to provide smoother and more symmetric segmentations than registration-based labeling, and were more robust when presented with input variations, thus outperforming the noisy ground truth. Our pipeline also includes uncertainty estimation and an explainability mechanism, hence providing features essential for anomaly detection and quality assurance. In summary, our study shows that deep learning models do achieve accurate brain segmentation in high-throughput quantitative preclinical imaging without the need for expensive expert-generated labels.

Characterization of the agriculture-livestock-environment integration system (sia2e) in the Maradi region along the north-center-south gradient

In Niger in general and in the Maradi region in particular, the management of space and natural resources leads to problems for agricultural and livestock farms. This study was conducted in the Maradi region in order to characterize the agriculture-livestock-environment integration system at the farm level in the Maradi region along the gradient of North (Dakoro), Center (Guidan Roumdji), South (Madarounfa). The methodology used to achieve this objective consisted of surveys of 300 households in the Maradi region, which were then analysed using Hierarchical Ascending Classification (HAC) and Principal Component Analysis (PCA). The results allowed us to distinguish three groups of farm sizes. Group 1 farms are characterized by large farms with an age greater than 41 years, a total cultivated area greater than 1 ha, and a large number of livestock greater than 3 UTF. These farmers are more represented in Dakoro (57%) and Guidan Roumdji (38%) and are more involved in Agriculture-Livestock-Environment than the other groups. As for group 2 farms, they are more numerous than group 1 farms in Guidan Roumdji (49%) and Madarounfa (49%). These farms have a cultivated area > 3 ha and a number of dependents between 5 and 14 peoples. The farms in group 3 are the least old and less numerous than those in groups 1 and 2, with very low values in Dakoro. This study categorized farmers in the Maradi region into three groups according to age, field area, household size and number of animals. It shows that agriculture-livestock-environment integration is practised by all the farms surveyed, but at different levels. Finally, particular attention was paid to the contribution of this agriculture-livestock-environment integration to improving soil fertility, household income and food and nutritional security.

Abstract 4124277: Resorcimoline, a Novel Free Radical Scavenger, Exhibits Cardioprotective Effects Following Coronary Ischemia-reperfusion Injury

Background: Ischemic heart disease remains the leading cause of death worldwide. Early coronary revascularization is the most important treatment. Recent findings have revealed that reactive oxygen species (ROS) can lead to tissue damage following coronary artery revascularization, known as ischemia-reperfusion injury. In this study, we focused on a novel free radical scavenger, resorcimoline (RML). Last year, we reported the scavenging activity of RML in vitro against multiple ROS, confirmed by the electron spin resonance spectrometry. Hypothesis: Resorcimoline might reduce ROS damage in cardiomyocytes, thereby exerting cardioprotective effects following coronary ischemia-reperfusion injury. Methods: Nine-to-eleven-week-old male Wistar rats were subjected to acute myocardial ischemia induced by ligation of the left anterior descending coronary artery for 30 minutes. Rats received intravenous injections of RML at 6 mg/kg before the ligation release or saline as a control. The heart sections were double-stained at 24-hour reperfusion with Evans blue and triphenyltetrazolium chloride to assess the infarct area. Cardiac function was evaluated at 2-day and 7-day reperfusion with echocardiography. Myocardial fibrosis was assessed at 7-day reperfusion by Masson’s trichrome staining. Primary cultured rat cardiomyocytes were treated with 10 μM angiotensin II for 3.5 hours and then exposed to RML for 30 minutes. Cellular ROS assay kits were used to assess the levels of ROS in the cardiomyocytes. Results: Infarct size in RML-treated animals was significantly smaller than in control animals (41.8±19.4% vs. 60.8±12.9%, p=0.03, Fig. 1A). Apoptotic cells in the border zone were significantly reduced in RML-treated animals (32.0±11.7% vs. 55.1±16.9%, p=0.01, Fig. 1B). Troponin I level in RML-treated animals was significantly lower than in control animals (p=0.04, Fig. 1C). Ejection fraction in RML-treated animals was significantly preserved at 2-day reperfusion and 7-day reperfusion when compared to control animals (p=0.001, p=0.003, Fig. 2A). Myocardial fibrosis area in RML-treated animals was significantly smaller than in control animals (23.9±11.7% vs. 40.6±15.6%, p=0.01, Fig. 2B). RML significantly reduced angiotensin II-induced ROS in cardiomyocytes in a concentration-dependent manner (Fig. 3A,B,C). Conclusion: Resorcimoline exhibits cardioprotective effects following coronary ischemia-reperfusion injury by reducing the infarct size and ROS damage in cardiomyocytes.

The weak association between hypoxia tolerance and thermal tolerance increases the susceptibility of abalone to climate change

The simultaneous occurrence of high temperatures and hypoxia events caused mass die-offs of aquatic animals. It is crucial to investigate the relationship between hypoxia tolerance and thermal tolerance of aquatic animals to predict the biological and ecological outcomes under global climate change scenarios. In this study, the hypoxia tolerance and thermal tolerance of Pacific abalone, Haliotis discus hannai, were measured by methods based on adhesion capacity (hypoxia adhesion duration and heat adhesion duration) and heart rate fluctuations (breakpoint of dissolved oxygen and Arrhenius breakpoint temperature). Weak correlations were found between hypoxia tolerance and thermal tolerance (Spearman correlation, r = −0.09, P = 0.2069; Pearson correlation, r = −0.04, P = 0.3313). Furthermore, a total of 21 significant SNPs and 19 candidate genes (such as cubn, lrp6, gria2, rft2, and casp8) were identified to be associated with hypoxia tolerance of Pacific abalone by conducting whole genome resequencing and genome-wide association study (GWAS). But there was no overlap between candidate genes associated with hypoxia tolerance and candidate genes associated with thermal tolerance, validating the weak correlation between hypoxia tolerance and thermal tolerance. This study highlights that individuals with greater hypoxia tolerance do not necessarily have greater thermal tolerance. Global warming and hypoxia may pose a greater threat to population size and genetic diversity of some aquatic animals than previously believed.

Study of acute and subacute toxicities and genotoxic and mutagenic potentials of the lyophilized extract of Campomanesia sessiliflora (O.Berg) mattos leaves in wistar rats

Campomanesia sessiliflora (O.Berg) Mattos is a Brazilian native plant species used in a popular medicinal tea for treating gastrointestinal, urinary, and dermatological pathologies. This study evaluated the toxicity of Campomanesia sessiliflora (O.Berg) Mattos via acute and subacute toxicity tests. It also analyzed mutagenic and genotoxic potentials by the micronucleus test, which detects genetic material damage indicating mutagenicity, and the comet assay, which assesses DNA damage levels as a genotoxicity indicator. The plant extract initially originated from the ultrasonic maceration of Campomanesia sessiliflora (O.Berg) Mattos leaves in a hydroethanolic solution. The involved animals were adult Wistar rats. Ten females were available to evaluate acute toxicity and estimate the LD50, receiving a dose of 2000 mg/kg. The subacute toxicity evaluation used 35 females and 35 males divided into seven groups: negative control (saline control – SC), positive control (cyclophosphamide control – CC), 125 mg/kg (125), 250 mg/kg (250), 500 mg/kg (500), 1000 mg/kg (1000), and the satellite group (ST). Genotoxicity and mutagenicity experiments applied bone marrow micronucleus and comet assays. Acute and subacute toxicity tests did not present behavioral, physical, and physiological changes (p≥0.05). Administering the Campomanesia sessiliflora (O.Berg) Mattos extract reduced spleen size in male and female animals, without histopathological changes. However, doses above 500 mg/kg showed significant genotoxic and mutagenic effects in the comet and micronucleus assays compared to the control group. The extract did not exhibit acute or subacute toxicity, but doses higher than 500 mg/kg indicated some level of genotoxicity and mutagenicity.

A new free radical scavenger, resorcimoline, prevents ischaemia/reperfusion injury in the heart

Abstract Introduction Ischaemic heart disease remains the leading cause of death worldwide. Early coronary revascularisation is the most important treatment. Recent findings have revealed that reactive oxygen species (ROS) can lead to tissue damage following coronary artery revascularisation, known as ischaemia-reperfusion injury. In this study, we focused on resorcimoline, a new free radical scavenger that was generated during the synthesis of dimethylresveratrol and dimethylpiceatannol. Last year, we reported the scavenging activity in vitro against multiple ROS, confirmed by the electron spin resonance spectrometry (Ref. 1). Purpose This study aimed to assess the potential of resorcimoline as a novel therapeutic treatment for reducing the degree of infarction caused by myocardial ischaemia, by eliminating ROS generated during myocardial ischaemia-reperfusion. Methods Nine-to-eleven-week-old male Wistar rats were subjected to acute myocardial ischaemia induced by ligation of the left anterior descending coronary artery for 30 minutes, followed by reperfusion for 24 hours. Rats received intravenous injections of resorcimoline at 6 mg/kg before coronary ligation or saline as a control (n = 9 vs. n = 8). The heart sections were double-stained with Evans blue 1% and triphenyltetrazolium chloride 1% to assess infarct area and area-at-risk. For immunohistochemical study, the other ischaemia/reperfusion models were treated with resorcimoline and saline (n = 7 vs. n = 7) as above, and the middle parts of the hearts were embedded in optimal cutting temperature compound and quickly frozen. In the H＆E-stained section, the infarct border zone was defined as a 2-mm band surrounding the necrosis area. Troponin I levels in serum were measured using ELISA. Primary cultured cardiomyocytes were treated with 10 μM angiotensin II for 3.5 hours and then exposed to resorcimoline for 30 minutes at an increasing dosage. A cellular ROS assay kit was used to assess the levels of ROS in the cardiomyocytes and the number of cells was counted with DAPI stain using an image processing software. Results Infarct size in resorcimoline-treated animals was significantly smaller than in control animals (41.8±19.4% vs. 60.8±12.9%, p=0.03, Fig. 1A) and area-at-risk was not significantly different (58.0±27.8% vs. 51.9±18.5%, p=0.61). Apoptotic cells in the border zone were significantly reduced in resorcimoline-treated animals (32.0±11.7% vs. 55.1±16.9%, p=0.01, Fig. 1B). Troponin I levels in resorcimoline-treated animals were significantly lower than in control animals (4524±3596 vs. 7856±4653, p=0.04, Fig. 1C). resorcimoline significantly reduced angiotensin II-induced ROS in cardiomyocytes in a concentration-dependent manner (Fig. 2A,B). Conclusion This novel compound, resorcimoline, can reduce infarct size induced by coronary ischaemia-reperfusion injury by reducing the ROS damage to myocardiocytes in the border zone and cellular ROS levels in cardiomyocytes.

Recent Advances and Applications of Passive Acoustic Monitoring in Assessing Shrimp Feeding Behaviour Under Laboratory and Farm Conditions

ABSTRACTThe use of passive acoustic monitoring (PAM) has recently been integrated with other noninvasive ethological methodologies to enhance the understanding of shrimp feeding behaviour, as their mandibles emit click sounds during food intake. This review aims to compile recent advances and various applications of PAM in assessing shrimp feeding behaviour under controlled laboratory and farm conditions. It includes a description of key concepts, terms and general methodologies in the field of bioacoustics to facilitate understanding of acoustic characterisation, specific methodologies and the main uses of PAM in shrimp research. Among the primary contributions of PAM in laboratory studies are acoustic characterisation of clicks and mandibular structures associated with their emission for different species; variations in acoustic click parameters related to animal size, feed texture and pellet size; and effects on feeding behaviour caused by shrimp size, stocking density and specific characteristics of artificial diets (texture, formulations, additives and pellet sizes). Finally, future perspectives and recommendations for laboratory studies using PAM are provided. The review highlights the contribution of PAM, which, allied with other ethological methodologies, emerges as a novel tool for researching shrimp behaviour and optimising feed management in aquaculture.

The Effects of Depth and Altitude on Image-Based Shark Size Measurements Using UAV Surveillance

Drones are an ecological tool used increasingly in shark research over the past decade. Due to their high-resolution camera and GPS systems, they have been used to estimate the sizes of animals using drone-based photogrammetry. Previous studies have used drone altitude to measure the target size accuracy of objects at the surface; however, target depth and its interaction with altitude have not been studied. We used DJI Mavic 3 video (3960 × 2160 pixel) and images (5280 × 3960 pixel) to measure an autonomous underwater vehicle of known size traveling at six progressively deeper depths to assess how sizing accuracy from a drone at 10 m to 80 m altitude is affected. Drone altitudes below 40 m and target depths below 2 m led to an underestimation of size of 76%. We provide evidence that accounting for the drone’s altitude and the target depth can significantly increase accuracy to 5% underestimation or less. Methods described in this study can be used to measure free-swimming, submerged shark size with accuracy that rivals hand-measuring methods.

Biochemical blood parameters in platinum fox females and males in ontogenesis

Currently, veterinarians pay much attention to the diagnostic examination of animals, including animals kept on fur farms. Blood is the main material used for such examinations. Changes in its composition allows veterinary practitioners to identify disorders in various systems and organs of animals, as well as to assess metabolism in animals. Results of biochemical tests of serum samples from platinum fox males and females of different age groups and comparative assessment thereof are presented. The levels of aspartate aminotransferase (U/L), alanine aminotransferase (U/L), alkaline phosphatase (U/L), total protein (g/L), albumin (g/L), urea (mmol/L), creatinine (μmol/L), α-amylase (U/L), cholesterol (μmol/L) were determined. Aspartate aminotransferase levels in females at the age of 6 months were lower by 69% than that ones in males. Increase in aspartate aminotransferase by the age of 6 months helps animals to accumulate body weight before winter. Sexual differences in the alkaline phosphatase levels were detected in 1.5-month-old kits: alkaline phosphatase levels were higher by 21.05% in males than in females. By the age of 6 months, the alkaline phosphatase levels decreased in both males and females. The decline in alkaline phosphatase level with the age is associated with participation of this enzyme in the development of animal skeleton during ontogenesis. From the age of 4 months, the growth and development of the skeleton slows down, and by the age of 6 months the animals gain the size and body weight of adult animals. Urea and creatinine levels in foxes of both sexes increased during their growth, but remained within the reference limits. Changes in urea levels in blood can be caused by feeding excessively high-protein or excessively low-protein diets. The total protein content in sera from 4 month-old males and females decreased by 32.51 and 43.24%, respectively, compared with that one in sera from animals at the age of 1.5 months, and increased at the age of 6 months up to the level observed at the age of 4 months. According to the literature, rather rapid stabilization of protein metabolism is a biological feature of many mammals born in spring, their growth rate is accelerated and, in general, the maturity phase is shortened.

Erythropoietin Reduces Inflammation, Oxidative Stress, and Apoptosis in a Rat Model of Bleomycin-Induced Idiopathic Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a lethal interstitial disease with unknown etiology and no effective cure, posing a great health burden to society. Erythropoietin (EPO) has been demonstrated to have protective roles in various tissues such as brain, spinal cord, heart, kidney and lung tissues. In this study, we investigate the specific anti-inflammatory, antioxidant and antiapoptotic effects of erythropoietin on lung tissue in a bleomycin-induced rat model of idiopathic pulmonary fibrosis. Recombinant human EPO or saline was injected, and the animals were monitored for 14 days after bleomycin instillation. Their hematocrit and serum EPO levels were determined. Histological and immunohistochemical analyses were performed. The extent of tissue injury, determined through morphometric analysis, was significantly decreased in size in animals treated with erythropoietin. An immunohistochemical analysis of the expression of cyclooxygenase-2 (COX-2), inducible synthase of nitric oxide (i-NOS), metalloproteinase-9 (MMP-9), erythropoietin receptor (EPO-R), and cytochrome-C (cyt-C) found these enzymes to be decreased in a statistically significant manner in animals treated with erythropoietin when compared to a non-treated group. The reduced expression of COX-2, i-NOS, MMP-9, EPO-R, and i-NOS in the lung tissues of animals treated with EPO indicates the anti-inflammatory, antioxidant and antiapoptotic action of erythropoietin, suggesting its potential therapeutic role in pulmonary fibrosis.

Optimising recovery of DNA from minimally invasive sampling methods: Efficacy of buccal swabs, preservation strategy andDNA extraction approaches for amphibian studies.

Studies in evolution, ecology and conservation are increasingly based on genetic and genomic data. With increased focus on molecular approaches, ethical concerns about destructive or more invasive techniques need to be considered, with a push for minimally invasive sampling to be optimised. Buccal swabs have been increasingly used to collect DNA in a number of taxa, including amphibians. However, DNA yield and purity from swabs are often low, limiting its use. In this study, we compare different types of swabs, preservation method and storage, and DNA extraction techniques in three case studies to assess the optimal approach for recovering DNA in anurans. Out of the five different types of swabs that we tested, Isohelix MS-02 and Rapidry swabs generated higher DNA yields than other swabs. When comparing storage buffers, ethanol is a better preservative than a non-alcoholic alternative. Dried samples resulted in similar or better final DNA yields compared to ethanol-fixed samples if kept cool. DNA extraction via a Qiagen™ DNeasy Blood and Tissue Kit and McHale's salting-out extraction method resulted in similar DNA yields but the Qiagen™ kit extracts contained less contamination. We also found that samples have better DNA recovery if they are frozen as soon as possible after collection. We provide recommendations for sample collection and extraction under different conditions, including budgetary considerations, size of individual animal sampled, access to cold storage facilities and DNA extraction methodology. Maximising efficacy of all of these factors for better DNA recovery will allow buccal swabs to be used for genetic and genomic studies in a range of vertebrates.

Cautionary tales on the use of proxies to estimate body size and form of extinct animals.

Body size is of fundamental importance to our understanding of extinct organisms. Physiology, ecology and life history are all strongly influenced by body size and shape, which ultimately determine how a species interacts with its environment. Reconstruction of body size and form in extinct animals provides insight into the dynamics underlying community composition and faunal turnover in past ecosystems and broad macroevolutionary trends. Many extinct animals are known only from incomplete remains, necessitating the use of anatomical proxies to reconstruct body size and form. Numerous limitations affecting the appropriateness of these proxies are often overlooked, leading to controversy and downstream inaccuracies in studies for which reconstructions represent key input data. In this perspective, we discuss four prominent case studies (Dunkleosteus, Helicoprion, Megalodon and Perucetus) in which proxy taxa have been used to estimate body size and shape from fragmentary remains. We synthesise the results of these and other studies to discuss nuances affecting the validity of taxon selection when reconstructing extinct organisms, as well as mitigation measures that can ensure the selection of the most appropriate proxy. We argue that these precautionary measures are necessary to maximise the robustness of reconstructions in extinct taxa for better evolutionary and ecological inferences.

Size Gynomimicry in the Sanmartinero Creole Bovine of the Colombian Orinoquia.

Variations in the size of animals of the same species but of different sex are called sexual size dimorphism. The aim of this study was to compare the biometrics between males and females of the Sanmartinero creole bovine, of Colombia, to establish if sexual dimorphism appears in the breed. A total of 94 animals (16 uncastrated males and 78 females, average age of 4.3 ± 1.4 and 4.2 ± 2.3 years, respectively) from three different farms were measured. A total of 21 linear variables were obtained using standard morphometric methods and live weight. A one-way NPMANOVA was used to evaluate between sexes, ages, and farms, a Principal Component Analysis was used to detect the most discriminating variables, and a multivariate regression used age as an independent value. Statistically significant differences were reflected between sexes (p = 0.033) and not by age and farms. The variables that differentiated the most between males and females were those related to size (thoracic circumference, body length, dorso-sternal diameter, height at the withers, height at the rump, and horn length), variables that were biased toward males, although only the height at the withers and the rump were the ones that presented statistically significant differences.

Effects of biochar addition on soil fauna communities—A meta‐analysis

AbstractSoil fauna is an important part of global biodiversity and plays a vital role in ecosystems. The microbial communities in soil fauna can have significant impacts on soil fertility, as microbial communities play a pivotal role in soil function by supporting ecological integrity and agricultural productivity. This study assesses the effect of biochar on soil fauna and response of microbial communities. Biochar is a highly porous organic carbon material, and the impact of biochar on microbial communities in soil fauna remains unclear. To date, no quantitative or comprehensive investigation has been undertaken to examine the effects of biochar on microbial communities in soil fauna. In this paper, we aim to quantify the effects of biochar on the abundance and diversity of soil fauna communities in various environments by conducting a meta‐analysis of 24 studies and analysing 459 observations. The impact of biochar on soil fauna communities was determined by analysing the responses of soil fauna that included differences in biochar feedstock, pH and pyrolysis, application rates and application times, as well as soil fauna with different physiological characteristics (body size, presence of exoskeletons). The results showed that biochar had a neutral (non‐significant) effect on the soil fauna community, with a total mean effect size (Hedge's g) = −0.04 (CI: −0.28; −0.20). Results Data validation using Egger regression showed no publication bias. Higher pH biochar and biochar from conventional pyrolysis were beneficial to soil fauna, but not significant (QM (df = 3) = 4.07, p = .25). In addition, body size of soil animals significantly reflected different sensitivities to biochar application, with Medium‐sized animals benefiting the most from biochar addition (0.35; CI: 0.05; 0.65; n = 6; 56). Animals with (n = 11; 125) and without exoskeletons (n = 17; 308) also showed favourable and unfavourable responses to biochar addition, respectively. This study can provide basic data for the evolutionary pattern of animal communities during biochar soil amendment, as well as information for the comprehensive evaluation of the environmental and biological effects of biochar.

A non-invasive approach to measuring body dimensions of wildlife with camera traps: A felid field trial.

Dimensions of body size are an important measurement in animal ecology, although they can be difficult to obtain due to the effort and cost associated with the invasive nature of these measurements. We avoid these limitations by using camera trap images to derive dimensions of animal size. To obtain measurements of object dimensions using this method, the size of the object in pixels, the focal length of the camera, and the distance to that object must be known. We describe a novel approach of obtaining the distance to the object through the creation of a portable distance marker, which, when photographed, creates a "reference image" to determine the position of the animal within an image. This method allows for the retrospective analysis of existing datasets and eliminates the need for permanent in-field distance markers. We tested the accuracy of this methodology under controlled conditions with objects of known size resembling Felis catus, our study species, validating the legitimacy of our method of size estimation. We then apply our method to measure feral cat body size using images collected in Tasmania, Australia. The precision of our methodology was evaluated by comparing size estimates across individual cats, revealing consistent and reliable results. The average height (front paw to shoulder) of the feral cats sampled was 25.25 cm (CI = 24.4, 26.1) and the average length (base of tail to nose) was 47.48 cm (CI = 46.0, 48.9), suggesting wild feral cats in our study area are no larger than their domestic counterparts. Given the success of its application within our study, we call for further trails with this method across a variety of species.