Morphometrical analysis of myelinated nerve fibers: is there a room for improvement?

Despite advancements in automatic approaches for histomorphometry analysis of peripheral nerves, manual and semi-automated methods are widely utilized. Standard software functions are often unsuitable for analysis due to their irregular shapes, especially in pathological conditions. This study aims to assess the reproducibility of nerves morphometric analysis and compare results obtained using both default and new alternative algorithms. Sciatic nerves from Wistar rats (untreated and after administration of intraperitoneal hydrargyrum chloride), previously embedded in resin, were used. Morphometric analysis (diameters, myelin thickness, g-ratio, and circularity) was conducted using ImageJ on semithin sections, with axon and myelin boundaries manually outlined. Default diameters were calculated as the mean of Feret diameters, with subsequent calculations for myelin thickness and g-ratio. The alternative approach estimated diameters based on the geometric center of axons, iterating through selected coordinates; myelin thickness was obtained using line equations. In the control group, inter-rater agreement was higher or within expected reliability (0.8 ± 0.05). However, in the experimental group, myelin thickness, g-ratio, and axon circularity showed lower agreement (0.66, 0.58, and 0.68, respectively) without visible patterns on Bland-Altman plots. The alternative approach did not reveal significant differences between approaches, except for g-ratio in the control group and fiber diameter in the experimental group (p < 0.05), with effect sizes of 0.29-0.30 and 0.19-0.20, respectively. This study highlights reduced agreement among investigators analyzing nerve fibers under pathological conditions, raising concerns about the current standard measurement methods. The proposed approach, based on a single geometric center, provides more natural estimations for irregular fibers, and can be implemented in automated nerve fibers acquisition systems.

Prevalence of intestinal parasites in humans and domestic animals in Jirel community, Dolakha, Nepal.

Introduction: Gastrointestinal (GI) parasites are major health concerns in both humans and domestic animals. Livestock farming is one of the common livelihood practices in rural Nepal. The proximity at human and domestic animal interface increases the chances of dissemination of enteric parasites, especially those of zoonotic importance. This study was aimed at finding the parasite prevalence and risk factors in both humans and their domestic animals in Jirel community. Materials and Methods: A field survey was conducted on the Jirel ethnic people and their domestic animals in Dolakha district, where a total of 152 fresh fecal samples from humans and domestic animals (cow, pigs, goats, chickens, ducks, and pigeons) were collected. The feces were examined by wet mounts and concentration techniques. A structured questionnaire survey was carried out among the local people and owners of the domestic animals to gather sociodemographic information, awareness, and hygienic practices in relation to parasite transmission. Results: The enteric parasite prevalence was found to be highest in goats (80.0%;12/15), followed by pigs (55.55%;5/9), cows (45.45%;6/11), chickens (11.7%;4/34), and humans (1.41%;1/71), while the fecal samples of ducks and pigeons did not contain any parasites. The only parasite identified in humans was Ascaris lumbricoides. Similarly, three genera of GI parasites (Eimeria sp., Strongyloides sp, and Trichuris sp.) from goats, two genera each from cow (Eimeria sp. and Strongyloides sp.), pigs (Entamoeba sp. and A. suum), and chickens (Eimeria sp. and Ascaridia galli), were detected. Conclusions: Based on the direct field observation, questionnaire survey and laboratory analysis, it is concluded that the Jirel community people are aware of health and hygiene; however, intervention measures are necessary to prevent parasitic infection in their domestic animals.

Text mining for disease surveillance in veterinary clinical data: part two, training computers to identify features in clinical text.

In part two of this mini-series, we evaluate the range of machine-learning tools now available for application to veterinary clinical text-mining. These tools will be vital to automate extraction of information from large datasets of veterinary clinical narratives curated by projects such as the Small Animal Veterinary Surveillance Network (SAVSNET) and VetCompass, where volumes of millions of records preclude reading records and the complexities of clinical notes limit usefulness of more "traditional" text-mining approaches. We discuss the application of various machine learning techniques ranging from simple models for identifying words and phrases with similar meanings to expand lexicons for keyword searching, to the use of more complex language models. Specifically, we describe the use of language models for record annotation, unsupervised approaches for identifying topics within large datasets, and discuss more recent developments in the area of generative models (such as ChatGPT). As these models become increasingly complex it is pertinent that researchers and clinicians work together to ensure that the outputs of these models are explainable in order to instill confidence in any conclusions drawn from them.

Influenza in feral cat populations: insights from a study in North-East Italy.

Influenza A virus (IAV) can cause high morbidity and mortality in domestic and wild avian species and it is able to infect mammals as well. IAV in cats is sporadic and self-limiting but the recent findings of high pathogenicity avian influenza virus (HPAIV) with genetic signatures of mammalian adaptation, in domestic cats, has raised new concerns about the potential role of cats in the virus ecology. The present study aimed to investigate the circulation of IAV in companion animals' shelters in North-eastern Italy. All samples were collected from feral cats living in feline colonies that were hosted in the companion animals' shelters for the requisite period to administer the veterinary treatments. Between 2021 and 2022, 389 oropharyngeal swabs and 279 sera were collected. All swabs tested negative for IAV and the only one ELISA positive serum sample resulted H5 positive by HI test with a titer of 1:80. Despite the sporadic occurrence of influenza in cats, continuous monitoring is crucial due to the evolving zoonotic nature of the virus.

Protective effect of bone marrow mesenchymal stem cells on the survival zone of the perforator flaps in rats.

Background: Perforator flaps have recently been used in the field of plastic surgery. Skin defects can be reconstructed to reach functional and cosmetic goals. With the development of reconstructive approaches, utilizing stem cells is a hopeful approach to enhance wound healing and tissue recovery. In this study, we assessed the effect of bone marrow mesenchymal stem cells on the perforator flap's survival in rats. Methods: Perforator flaps (2.5 × 11 cm) were transplanted into rats and focused on the thoracodorsal, intercostal, and deep circumflex arteries, which were randomly divided into three groups: control, saline, and bone marrow mesenchymal stem cells (7 × 106 ml). Seven days after the surgery, tissue edema, inflammation, and discharge were observed and photographed. Histological analyses were performed to determine flap survival. Hematoxylin and eosin staining was performed to assess levels of microvascular density determined in skin flaps. Results: Rats in the bone marrow mesenchymal stem cells group exhibited higher average flap survival area, and higher microvascular density levels at the dynamical regions of the flaps compared with the other two groups. Subdermal injection of bone marrow mesenchymal stem cells significantly increased ischemic perforator flap survival due to stimulated neovascularization in rats. Conclusion: Our findings suggest the potential usefulness of bone marrow mesenchymal stem cells in preventing skin flap perforator tissue necrosis.

Evaluation of the Epidemic Situation of Anthrax in Armenia Over the Last Decade.

INTRODUCTION: Anthrax is a World Organisation for Animal Health (WOAH)-listed disease that must be reported upon confirmation based on the Terrestrial Animal Health Code. Anthrax poses a serious health issue for unvaccinated livestock, is a threat to humans through interaction with contaminated livestock and animal products and is endemic in many areas throughout the world, including the Transcaucasian Region. Despite several control and eradication efforts that have been implemented by the government of the Republic of Armenia (RA), sporadic cases of anthrax are still reported. We sought to understand the epidemic situation of anthrax in RA during the last 10 years (2012-2023) based on analysis of outbreaks and reported cases in cattle and humans. METHODS: We collected and evaluated officially reported data from human and animal cases, such as time, location, animal species, disease intensity and spread radius. The data and various parameters were mapped using ArcGIS to prepare a viable risk assessment. RESULTS: Based on the officially available data and reports, there have been 80 human cases and 55 animal cases of anthrax confirmed in RA from 2012 to 2023. We also identified the presence of anthrax spores in soil and environmental samples near animal burial sites in RA in 2015-2017 through polymerase chain reaction (PCR) testing. Upon comparing the human and animal cases by frequency and intensity, the human cases are directly proportional to the animal husbandry practices performed in RA. CONCLUSION: The detection of the anthrax pathogen at the burial sites highlights the continued threat in these areas. Thus, it is imperative to secure and monitor any areas that have been used for anthrax burial and limit the movement of animals in these areas. In the future, legislation should be updated to prioritise incineration of anthrax-infected carcasses instead of burial to limit further exposure to animals and humans.

Escherichia coli from healthy farm animals: Antimicrobial resistance, resistance genes and mobile genetic elements.

The use of antibiotics in agriculture and subsequent environmental pollution are associated with the emergence and spread of multidrug-resistant (MDR) bacteria including Escherichia coli. The aim of this study was to detect antimicrobial resistance, resistance genes and mobile genetic elements of 72 E. coli strains isolated from faeces of healthy farm animals. Disk diffusion test showed resistance to ampicillin (59.7%), tetracycline (48.6%), chloramphenicol (16.7%), cefoperazone and ceftriaxone (13.9%), cefepime and aztreonam (12.5%), norfloxacin and ciprofloxacin (8.3%), levofloxacin (6.9%), gentamicin and amikacin (2.8%) among the studied strains. Antibiotic resistance genes (ARGs) were detected by polymerase chain reaction: the prevalence of blaTEM was the highest (59.7% of all strains), followed by tetA (30.6%), blaCTX-M (11.1%), catA1 (9.7%), less than 5% strains contained blaSHV, cmlA, floR, qnrB, qnrS, tetM. 26.4% of E. coli strains had a MDR phenotype. MDR E. coli more often contained class 1 integrons, bacteriophages, conjugative F-like plasmids, than non-MDR strains. ARGs were successfully transferred from faecal E. coli strains into the E. coli Nissle 1917 N4i strain by conjugation. Conjugation frequencies varied from (1.0 ± 0.1) * 10-5 to (7.9 ± 2.6) * 10-4 per recipient. Monitoring mobile genetic elements of E. coli for antibiotic resistance is important for farm animal health, as well as for public health and food safety.

Germline mutation rate predicts cancer mortality across 37 vertebrate species.

Background and objectives: Cancer develops across nearly every species. However, cancer occurs at unexpected and widely different rates throughout the animal kingdom. The reason for this variation in cancer susceptibility remains an area of intense investigation. Cancer evolves in part through the accumulation of mutations, and therefore, we hypothesized that germline mutation rates would be associated with cancer prevalence and mortality across species. Methodology: We collected previously published data on germline mutation rate and cancer mortality data for 37 vertebrate species. Results: Germline mutation rate was positively correlated with cancer mortality (P-value = 0.0008; R2 = 0.13). Controlling for species' average parental age, maximum longevity, adult body mass or domestication did not improve the model fit (the change (Δ) in Akaike Information Criterion (AIC) was less than 2). However, this model fit was better than a model controlling for species trophic level (ΔAIC > 2). Conclusions and implications: The increased death rate from cancer in animals with increased germline mutation rates may suggest underlying hereditary cancer predisposition syndromes similar to those diagnosed in human patients. Species with higher germline mutation rates may benefit from close monitoring for tumors due to increased genetic risk for cancer development. Early diagnoses of cancer in these species may increase their chances of overall survival, especially for threatened and endangered species.

Assessing leptospirosis and toxoplasmosis seropositivity in wild boars (Sus scrofa): Implications for public and animal health in Southern Brazil.

Leptospirosis and toxoplasmosis are re-emerging zoonosis caused by infection with pathogenic spirochaetes of Leptospira and the protozoa Toxoplasma gondii, respectively. Wild boars (Sus scrofa), an exotic invasive species in Brazil, could play a role in the diseases' epidemiological cycles, but this issue is still unexplored. This study aimed to evaluate the Leptospira spp. and T. gondii seropositivity in wild boars in Rio Grande do Sul state, south Brazil. Of evaluated animals, 16% (13/80) and 85% (52/61) had antibodies to T. gondii and Leptospira spp., respectively. Sex, weight, age, hunt location and season of hunt were evaluated by their association with seropositivity for both pathogens, but none of them had statistical significance. This study revealed that wild boars should be considered as a potential source of Leptospira spp. and T. gondii dissemination for humans and animal species in shared environments in Rio Grande do Sul state.

Occurrence, multidrug resistance and potential risk factors for Staphylococcus aureus infection at worker-animal and working equipment interfaces: a systematic review and meta-analysis of the Ethiopian literature.

Background: Staphylococcus aureus (S. aureus) infecting animals and humans via close contact, handling, or consuming contaminated products is a growing public health concern. In Ethiopia, it is important to examine the overall prevalence of S. aureus, patterns of multidrug resistance, and potential risks in human-animal interface settings. Thus, this review was conducted to estimate the pooled prevalence of S. aureus, its multidrug resistance, and potential risk factors for worker-animal-working equipment interactions. Methods: This systematic review and meta-analysis were carried out by the PRISMA guidelines. The research articles were searched from PubMed, HINARI, Web of Sciences, and Google Scholar databases. Results: This meta-analysis included 13 independent articles and 52 dependent studies. In total, 5,329 humans, 5,475 animals, and 5,119 samples of working equipment were analyzed. The pooled prevalence of S. aureus at the interfaces between humans, animals, and working equipment was 22%, there was a high level of heterogeneity (I2 = 94%: p < 0.01). The overall pooled prevalence of S. aureus in dairy farm sources was 23% (95% CI, 17-30%) compared to 18% in abattoirs. The pooled prevalence of S. aureus was estimated to be 25% for human sources, 23% for animal sources, and 19% for working equipment. The total multidrug resistance (MDR) rate was 27%. The present study illustrates that a predominant antimicrobials comprising ampicillin, penicillin, chloramphenicol, tetracycline, and ciprofloxacin, accounts for the development of resistance in S. aureus strains, with a prevalence of 72%. According to the qualitative assessment of potential risk factors, animal age, worker education, lactation stage, and hand washing by milkers influenced the circulation of S. aureus at animal-worker and working equipment interfaces. Conclusion: The pooled prevalence of S. aureus at the interface of human,-and animal-working equipment was quantified at 22%. S. aureus was found in humans, animals, and equipment at nearly the same rate. The results of this study demonstrate that S. aureus is hazardous and circulates among animals, workers, and equipment: farmers, animal owners, employees, and the public need to be educated about S. aureus. Moreover, animals and work equipment should be included in the control and prevention of S. aureus infection.

An unsuspected extracranial internal carotid pseudoaneurysm following dog bites: a case report and review of literature.

BACKGROUND: Extracranial internal carotid artery (ICA) pseudoaneurysm is a rare condition that can be caused either by penetrating or blunt trauma, including dog bites, which is an uncommon occurrence. Together with the possibility of no symptoms or nonspecific ones such as cervical pain, hematoma, swelling, or mass, considering ICA pseudoaneurysm following a dog attack is of paramount importance to avoid life-threatening complications. CASE PRESENTATION: We present a rare case of a 17-year-old male with a history of dog bites three months prior, who presented to the emergency department with left-sided neck pain, dizziness, and several episodes of blurred vision and diplopia. On physical examination, a palpable mass measuring approximately 20 × 30 millimeters was identified in the left neck region and multiple superficial lacerations were observed in this area. Laboratory tests yielded normal results. Doppler ultrasound revealed a pseudoaneurysm in the left internal carotid artery. Because the great saphenous veins were insufficient, the patient was successfully treated with synthetic graft patch arterioplasty, and no complications were seen in his one-year follow-up with computed tomography (CT) angiography. CONCLUSIONS: This report emphasizes the significance of thorough initial evaluation and imaging in cases of dog attacks, even without apparent significant trauma, to rule out hidden arterial injuries.

SARS-CoV-2 infection of domestic animals and their role in evolution and emergence of variants of concern.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that is responsible for COVID-19 pandemic, is a zoonotic RNA virus that has been reported in animals, including domestic animals. Due to the growing concern of health threat that could arise from active transmission of SARS-CoV-2 between pet owners and their pets, there is need to monitoring the emergence of a highly pathogenic strain of SARS-CoV-2 that is capable of transboundary infection, or a serious outbreak among human populations. Methods: We carried out a search in English, on PubMed and NCBI (National Center for Biotechnology Information) SARS-CoV-2 resources for relevant journals and nucleotide sequence data, that were published between 2019 and 2023. The CoVsurver mutations application on GISAID webpage was used to analyse mutation, nucleotide sequence alignment was carried out using MAFFT (Multiple Alignment using Fast Fourier Transform) version 7 and maximum likelihood tree was constructed by bootstrapping with 1000 replicates on MEGA 11 software. Results: A total of 47 mutations at the Spike gene region were identified, and mutation D614 was the most observed mutation. Nucleotide sequences of isolates from domestic animals had high sequence identity with Wuhan-Hu-1 reference sequence and the representative sequences of previously circulating VOCs from humans. Conclusion: This reveals that there is spill over of previously circulating variants of concern (VOC) to household pets from their infected owners. Hence, there is an urgent need for more intense surveillance to be carried out globally to monitor evolution of SARS-CoV-2 coronaviruses as a result of human - pet association.

The curious case of the rare Citrobacter pasteurii isolated from an endangered primate in Brazil.

The genus Citrobacter comprises clinically important human pathogens but has been less frequently associated with wildlife infections. Citrobacter pasteurii was first identified as causing human diarrhea and remains rarely documented. In this study, a Gram-negative bacterial strain, named A318, was identified as causing diarrhea in a black lion tamarin. This strain was biochemically identified as Trabulsiella guamensis, a species of unusual nature, and was submitted to whole-genome characterization. Curiously, phylogenomic analysis showed that A318 strain belonged to the genus Citrobacter, with confirmation of the species C. pasteurii by average nucleotide identity (99.02 %) and digital DNA-DNA hybridization (93.80 %) analyzes. Cases of misidentification of C. pasteurii as Citrobacter youngae were detected and corrected in this study. In addition to the genome sequence of the type strain of C. pasteurii, only two others from the Australian cockle and Portuguese silver gull are publicly available. Single nucleotide polymorphism differences among all C. pasteurii indicated a highly diverse population. No acquired antimicrobial resistance genes and plasmid replicons were found. Therefore, our findings emphasize the importance of gold-standard methods for accurate identification and underscores the importance of continued surveillance and research to mitigate the risks posed by zoonotic and zooanthroponotic pathogens.

The constructive nature of memories in insects: bumblebees as a case study.

The view that human memory is constructive implies that recollections are not necessarily an accurate reproduction of past events. An approach to study this constructive nature of memory is by examining memory errors. In this regard, conjunction errors-i.e. incorrect recollection of new stimuli integrated by components from two previously studied stimuli-have attracted important attention in human memory research. Do animals other than humans make conjunction errors? To investigate this issue, a choice task in which training was not involved was used. Bees experienced two to-be-remembered stimuli. At the test, they were presented with four stimuli: one of the original items (i.e. old), an item made by combining two features of the original items (i.e. conjunction), an item containing a previously presented feature and a new one (i.e. feature), and an item integrated solely by new features (i.e. new). Bumblebees remembered the old items. Importantly, when making memory errors, bumblebees selected conjunction and feature lures more often than new items. These results indicate that bumblebees, like humans, spontaneously make memory conjunction errors and suggest that invertebrates' memories might also be constructive in nature. I suggest that focusing on memory errors is a solid avenue to investigate episodic (like) memory in animals.This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'.

"Veterinary medicine is not finished when I have diagnosed an incurable disease, that's when it starts for me." A qualitative interview study with small animal veterinarians on hospice and palliative care.

In the wake of recent medical developments in small animal practice, curing animals of their illnesses and restoring their health can be realized better than ever before. However, the growing medical possibilities are also leading to an increase in demand for better care for patients suffering from terminal illnesses. Consequently, the field of animal hospice and palliative care has become increasingly available, enabling veterinarians to optimize the quality of life of patients, such as dogs and cats, who no longer have a prospect of full recovery. Using qualitative, semi-structured interviews with 20 small animal veterinarians involved in hospice and palliative care, we investigated the factors that motivate veterinarians to become involved in hospice and palliative care and explored the importance of relationships, communication, time and infrastructure in this area. Findings show that personal experiences with their own pets or during training or work life motivated veterinarians to provide this service. Although veterinarians highlighted the importance of empathetic-driven relationships, they were aware that keeping an emotional distance from the patient and caregiver is significant to provide successful care. Further, veterinarians emphasized their high investment of time that resulted primarily from the increased frequency and provided opportunities to communicate with caregivers. The overall conclusion is that having time for patients and the patients' caregivers is one of the most important aspects of work in this field. However, as it will be also shown, veterinarians must consider aspects of self-care management by reflecting on their own time and energy resources while caring for animals and their caregivers.

Neutralisation techniques used by defendants charged with animal welfare offences in Finland.

Animal welfare offences encompass a heterogeneous range of crimes, including violence and various forms of negligence toward animals' needs. However, there is limited understanding of the offenders' rationalisations concerning their criminal behaviour against animals, despite this information being essential for enhancing the prevention of these crimes. Our data comprised 1,443 judgements in animal welfare offences in Finland between January 2011 and May 2021. We categorised the rationalisations used by defendants and identified differences between offender profiles according to the offence type. Nearly all defendants responded to the charges. Overall, defendants appealed most often to their challenging circumstances, e.g. a lack of resources. Defendants charged with offences against production animals offered more explanations than the other defendants and often denied their responsibility for the animals, or having caused them any harm, and appealed to financial problems, weather conditions, and having too many animals. Moreover, they frequently challenged the norms, appealing in particular to the immorality of the authorities, who were mostly official veterinarians. Defendants charged with animal hoarding offences rationalised their actions similarly to animal farmers, whereas those charged with violent crimes against animals more often cited provocative or otherwise problematic behaviour of the animal victim. Our results support the observation that farmers may perceive official animal welfare supervision negatively. Violent animal welfare crimes and animal hoarding stand out as distinctive types of crime at the level of rationalisations. The differences between offence types and offenders' underlying motivations should be considered when developing animal welfare control, agricultural support systems, and crime prevention.

Eco-toxicological effects assessment: comparative characteristics of environmental conditions and status of vertebrate indicator species in the "Dnepr" launch vehicle accident zone.

Space rockets are regularly launched from the Baikonur Cosmodrome in Kazakhstan. The ecological impact of territories affected by the consequences of space rocket activities on the environment is a significant concern. On July 27, 2006, the Dnepr rocket was launched from the Baikonur Cosmodrome, resulting in an abnormal situation and its emergency fall. The rocket fuel components, heptyl, and amyl, led to decontamination and reclamation activities. However, the self-restoration of soil and vegetation cover is currently in the earliest stages. Consequently, an assessment of the remote consequences of the accidental fall of the Dnepr launch vehicle for environmental objects was conducted. The study involved eco-toxicological characterization of habitat conditions, assessment of species diversity, determination of key morphophenetic indicators, and the genetic status of indicator species as the main parameters. The results revealed an increased level of genotoxicity in soils at the accident site. While there were deviations from the norm in some morphophenetic and cytogenetic parameters in indicator animals, they were not critical for their existence in this territory. Possibly, at the physiological level, they exhibit a high enough adaptation potential and compensatory mechanism.

Companion animals and child development outcomes: longitudinal and cross-sectional analysis of a UK birth cohort study.

BACKGROUND: Research into the impact of social relationships on childhood and adolescent health and wellbeing has been largely limited to children's relationships with other humans, while studies into the impact of pet ownership are sparse and have generally not adjusted for potential confounders. This study aimed to investigate the association between pet ownership and a range of developmental outcomes in childhood and adolescence. METHODS: Data were self-reports and direct assessments of approx. 14,000 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Multivariable regression models adjusting for confounding factors examined associations between developmental outcome measures (emotional health, behavioural development, cognitive development, language development, educational attainment) and concurrent pet ownership, including species, and also longitudinal pet ownership history and pet-interaction where possible. Analyses model numbers using multiple imputation varied from n = 393-8963. RESULTS: In cross-sectional analyses, owning a dog (b = 0.24, [0.06-0.41], p = .004) and owning other/miscellaneous pets (b = 0.18, [0.03-0.33], p = .021) at age 3 were associated with higher prosocial behaviour score. Owning a pet was associated with a higher non-verbal communication score at age 2 (cross-sectional, b = 0.18, [0.04-0.32], p = .014), and a higher language development score at age 5 (cross-sectional, b = 1.01, [0.18-1.83], p = .017). However, pet ownership was associated with lower educational attainment across a number of academic subjects and timepoints, in both cross-sectional and longitudinal analyses. It was also cross-sectionally linked to hyperactivity at age 3 and conduct problems at age 3 and 11. Furthermore, at age 8, cross-sectional analysis showed that children who owned any pets (OR [95% CI]: 0.85 [0.73-0.98], p= ·026) or cats (0.83, [0.73-0.95], p= ·006) had lower odds of high self-esteem (scholastic competence). CONCLUSIONS: Using a large, well-designed longitudinal study and adjusting for key confounders, we found little evidence of cross-sectional or longitudinal associations between pet ownership and emotional health or cognitive outcomes in children. There may, however, be some cross-sectional and longitudinal association with poorer educational attainment and a positive impact on social interactions as seen through associations with enhanced language development and prosocial behaviour. This study demonstrates the importance of adjustment for confounding variables and suggests that, contrary to popular belief, positive impacts of pet ownership on childhood development may be mainly limited to social behaviour and language development.