Frontiers in Veterinary Science
Latest articles in this journal
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.1064836
Background: Myocardial infarction (MI) is one of the most common cardiac problems causing deaths in humans. Previously validated anesthetic agents used in MI model establishment are currently controversial with severe restrictions because of ethical concerns. The combination between medetomidine, midazolam, and butorphanol (MMB) is commonly used in different animal models. The possibility of MMB combination to establish the MI model in rats did not study yet which is difficult because of severe respiratory depression and delayed recovery post-surgery, resulting in significant deaths. Atipamezole is used to counter the cardiopulmonary suppressive effect of MMB.Objectives: The aim of the present study is to establish MI model in rats using a novel anesthetic combination between MMB and Atipamezole.Materials and methods: Twenty-five Sprague Dawley (SD) rats were included. Rats were prepared for induction of the Myocardial infarction (MI) model through thoracotomy. Anesthesia was initially induced with a mixture of MMB (0.3/5.0/5.0 mg/kg/SC), respectively. After endotracheal intubation, rats were maintained with isoflurane 1% which gradually reduced after chest closing. MI was induced through the left anterior descending (LAD) artery ligation technique. Atipamezole was administered after finishing all surgical procedures at a dose rate of 1.0 mg/kg/SC. Cardiac function parameters were evaluated using ECG (before and after atipamezole administration) and transthoracic echocardiography (before and 1 month after MI induction) to confirm the successful model. The induction time, operation time, and recovery time were calculated. The success rate of the MI model was also calculated.Results: MI was successfully established with the mentioned anesthetic protocol through the LAD ligation technique and confirmed through changes in ECG and echocardiographic parameters after MI. ECG data was improved after atipamezole administration through a significant increase in heart rate (HR), PR Interval, QRS Interval, and QT correction (QTc) and a significant reduction in RR Interval. Atipamezole enables rats to recover voluntary respiratory movement (VRM), wakefulness, movement, and posture within a very short time after administration. Echocardiographic ally, MI rats showed a significant decrease in the left ventricular wall thickness, EF, FS, and increased left ventricular diastolic and systolic internal diameter. In addition, induction time (3.440 ± 1.044), operation time (29.40 ± 3.663), partial recovery time (10.84 ± 3.313), and complete recovery time (12.36 ± 4.847) were relatively short. Moreover, the success rate of the anesthetic protocol was 100%, and all rats were maintained for 1 month after surgery with a survival rate of 88%.Conclusion: Our protocol produced a more easy anesthetic effect and time-saving procedures with a highly successful rate in MI rats. Subcutaneous injection of Atipamezole efficiently counters the cardiopulmonary side effect of MMB which is necessary for rapid recovery and subsequently enhancing the survival rate during the creation of the MI model in rats.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.1033463
Introduction: Tail biting is a widespread problem in pig production systems and has a negative impact on both animal welfare and farm income. This explorative study aims to validate how tail biting is related to general behaviors at the individual level and explore whether these behaviors are related to a particular type of tail biting: two-stage, sudden-forceful, obsessive, or epidemic.Methods: This research was conducted in a standard commercial setting where 89 tail-docked pre-finishing piglets divided into 8 groups were observed 4 days per week from 5 to 8 weeks of age. Each piglet was observed for a total of 160 min using continuous focal sampling. Ten individual behaviors were recorded based on the general behaviors expected to be linked to giving tail biting (PCA1), receiving tail biting (PCA2), and tail biting damage (PCA3). These PCAs were assembled and related to tail biting given, tail biting received, and tail biting lesions.Results: Tail biting did not lead to major damage on the piglets' tail at 8 weeks of age but was observed 420 times, where most of the individuals (72%) were categorized as “biters and victims.” When relating PCA1 with tail biting given, piglets that gave more tail biting showed more “active exploration.” When relating PCA2 with tail biting received, piglets receiving more tail biting were more “explored while active” and “attacked and explored.” When relating PCA2 with tail biting lesions, piglets presenting lesions showed more “agonism.” Surprisingly, tail biting lesions were not significantly related to PCA3. The relationship between explorative behaviors and tail biting indicates that the pre-damage stage of two-stage tail biting was the predominant tail biting type, while the damaging stage was likely incipient. The relationship between tail biting and aggression, as well as the minor tail lesions observed suggest that sudden-forceful tail biting was probably present even though it was rarely seen. Obsessive and epidemic tail biting were not observed.Discussion: This study demonstrates that studying tail biting at the individual level helps to identify the type of tail biting present. This gives directions to farmers for applying appropriate measures to prevent the development of tail biting behavior in piglets.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.1071097
Lumpy skin disease virus (LSDV) causes lumpy skin disease (LSD) in livestock, which is a double-stranded DNA virus that belongs to the genus Capripoxvirus of the family Poxviridae. LSDV is an important poxvirus that has spread out far and wide to become distributed worldwide. It poses serious health risks to the host and causes considerable negative socioeconomic impact on farmers financially and on cattle by causing ruminant-related diseases. Previous studies explained the population structure of the LSDV within the evolutionary time scale and adaptive evolution. However, it is still unknown and remains enigmatic as to how synonymous codons are used by the LSDV. Here, we used 53 LSDV strains and applied the codon usage bias (CUB) analysis to them. Both the base content and the relative synonymous codon usage (RSCU) analysis revealed that the AT-ended codons were more frequently used in the genome of LSDV. Further low codon usage bias was calculated from the effective number of codons (ENC) value. The neutrality plot analysis suggested that the dominant factor of natural selection played a role in the structuring of CUB in LSDV. Additionally, the results from a comparative analysis suggested that the LSDV has adapted host-specific codon usage patterns to sustain successful replication and transmission chains within hosts (Bos taurus and Homo sapiens). Both natural selection and mutational pressure have an impact on the codon usage patterns of the protein-coding genes in LSDV. This study is important because it has characterized the codon usage pattern in the LSDV genomes and has provided the necessary data for a basic evolutionary study on them.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.952382
Foot-and-mouth disease is an acute, highly infectious, and economically significant transboundary animal disease. Vaccination is an efficient and cost-effective measure to prevent the transmission of this disease. The primary way that foot-and-mouth disease spreads is through direct contact with infected animals, although it can also spread through contact with contaminated environments. This paper uses a diffuse foot-and-mouth disease model to account for the efficacy of vaccination in managing the disease. First, we transform an age-space structured foot-and-mouth disease into a diffusive epidemic model with nonlocal infection coupling the latent period and the latent diffusive rate. The basic reproduction number, which determines the outbreak of the disease, is then explicitly formulated. Finally, numerical simulations demonstrate that increasing vaccine efficacy has a remarkable effect than increasing vaccine coverage.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.1038362
Asia is responsible for ~60% of global egg production. As in most of the world, nearly all of the egg-laying hens are housed in cages. While there is growing demand for cage-free eggs in many regions of the world, challenges have been reported when transitioning to these systems, which may affect the willingness of producers to transition. The aim of this research was to investigate the views of Asian egg producers on the feasibility of cage-free systems and what they perceive to be the main challenges and proposed solutions in adopting cage-free systems. A total of 224 egg producers (165 cage egg producers) completed questionnaires containing a mix of free-form, Likert scale and demographic items. Data were analyzed using thematic qualitative analysis and descriptive quantitative statistics. Responses indicated that cages are primarily used for their efficiency and ease of management. The most common reasons to consider adopting cage-free systems included improved animal welfare, increased market access, and increased product quality. A majority of producers (65%) responded “yes” or “maybe” when asked if they consider cage-free systems to be feasible in their country. Perceived challenges in adopting cage-free systems included reduced profitability, higher costs, and biosecurity and disease. Potential solutions included the development of the cage-free industry and market development. Most producers (72%) said more support is needed to establish cage-free farms, mostly pertaining to technical advice, training and resources. The findings of this study provide an enhanced understanding of the egg industry in these countries and potential areas for producer support in transitioning to cage-free systems.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.992882
Digital technology is being introduced to global agriculture in a wide variety of forms that are collectively known as digital agriculture. In this paper we provide opportunities and value propositions of how this is occurring in livestock production systems, with a consistent emphasis on technology relating to animal health, animal welfare, and product quality for value creation. This is achieved by organizing individual accounts of digital agriculture in livestock systems according to four broad types—commodity-based; value seeking; subsistence and nature-based. Each type presents contrasting modes of value creation in downstream processing; as well as from the perspective of One Health. The ideal result of digital technology adoption is an equitable and substantial diversification of supply chains, increased monetization of animal product quality, and more sensitive management to meet customer demands and environmental threats. Such changes have a significance beyond the immediate value generated because they indicate endogenous growth in livestock systems, and may concern externalities imposed by the pursuit of purely commercial ends.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.1052327
Objective: The purpose of this study was to quantify three-dimensional (3D) stifle kinematics during walking in dogs with complete cranial cruciate ligament insufficiency (CCL-I) treated with a CORA-based leveling osteotomy (CBLO).Study design: Four client-owned dogs with unilateral complete CCL-I were prospectively enrolled. Custom digital 3D models of the femora and tibiae were created from pre-and postoperative computed tomographic scans for each dog. Lateral view fluoroscopic images were collected during treadmill walking preoperatively and 6 months after CBLO. Results were generated using a 3D-to-2D image registration process. Pre-and postoperative stifle kinematics (craniocaudal translation, extension angle) were compared to that of the unaffected contralateral (control) stifle. Force plate gait analysis was performed, and symmetry indices (SI) were calculated for peak vertical force (PVF) and vertical impulse (VI).Results: After CBLO, craniocaudal femorotibial motion was reduced by a median (range) of 43.0 (17.0–52.6) % over the complete gait cycle. Median (range) PVF SI was 0.49 (0.26–0.56) preoperatively and 0.92 (0.86–1.00) postoperatively, and VI SI was 0.44 (0.20–0.48) preoperatively and 0.92 (0.82–0.99) postoperatively.Conclusion: CBLO mitigated but did not fully resolve abnormal craniocaudal translation; lameness was substantially improved at 6 months.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.1038855
The COVID-19 pandemic has had a significant impact on the tourism industry, especially in Thailand. Starting in April 2020, the Thai government banned international travel and all elephant tourist camps closed. A wide variety of management changes were implemented because of the lack of income from tourists. This study surveyed 30 camps that cared for >400 elephants in northern Thailand to obtain information on camp, elephant, and mahout management during the COVID-19 pandemic from April 2020 to 2022 compared to the year before. The survey consisted of questionnaires that interviewed elephant camp owners, managers, veterinarians, and mahouts, and captured information on changes in camp operations, including numbers of tourists, elephants and mahouts, elephant and mahout activities, and veterinary care. Results revealed significant changes in camp structure, elephant work activities and general care. Staff layoffs led to a decrease in the ratio of mahouts to elephants from 1:1 to 1:2. Elephant activities, distance walked, and amounts of food were reduced when compared to pre-COVID-19, while chain hours were increased due to reduced activity. Overall, the COVID-19 crisis altered elephant management significantly, potentially affecting animal welfare resulting from changes in nutrition, health, exercise, and numbers of mahouts. We hope to use these data to develop better management plans and guidelines for elephant camps in Thailand so they can cope with the current and potential imminent pandemics that result in decreased tourism income. A follow-up study will measure health and welfare markers in relation to COVID-19 induced changes to determine if any camps adapted management to still meet elephant health and welfare needs, and could serve as models for responding to future pandemics.
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.1102122
Editorial on the Research TopicCaptive animal behavior: Individual differences in learning and cognition, and implications on animal welfare To provide adequate welfare for animals in captivity, it is important to consider not only the needs of the species, but also those of the individual. In this context, knowledge about individual differences in learning and cognitive functioning are of particular importance, as it can help to assess the extent to which captive animals are able to adapt and respond to changing housing conditions. In the last decades, individual differences in learning and cognition have been studied systematically across a wide range of taxa (1). However, the underlying factors that cause this variation, as well as its potential welfare consequences, are still under debate (2). While ultimate factors tend to play a minor role in explaining behavioral variation in captive animals, a variety of proximate factors could be responsible for the individual variation we see in animals' performance in learning and cognitive tasks (Finkemeier et al.). These factors include a variety of genetic and environmental components, ranging from breed or feeding type, to housing conditions (single vs. group housed), to idiosyncrasies of different research sites (3–5). The observation of robust intra-species variation in behavior under identical environmental conditions has led to a significant increase in research on inter-individual behavioral variation, often coined as personality, in many animal taxa, especially in the field of behavioral ecology (6). This behavioral variation can be observed in levels of activity, as well as exploratory and social behaviors, beside others. While the influence of genetic, physiological and behavioral factors on individual response patterns in farm, laboratory, and zoo animals has received considerable attention in recent years, few studies have addressed the role of these traits in predicting inter-individual differences in learning and cognition. The objective of this Research Topic was to promote interdisciplinary research approaches on the link between individual variation in genetics, physiology and behavior, and learning and cognition—ranging from fields such as developmental psychology to applied ethology and addressing this variation in animals under human care, with particular emphasis on farm, companion and zoo animals. The manuscripts included in this Research Topic have examined the impact of genetics, neurotransmitters, hormones, critical life stages, and certain personality traits on learning and cognitive phenomena such as cooperation and self-control and range from farm animals (goat, pig, and chicken) to companion (dog, horse) and laboratory animals (rat) as studied species. Studies in our Research Topic often focused on the association between different behavioral parameters and inter-individual differences in learning and other cognitive phenomena. In a study in goats, Finkemeier et al. investigated the relationship between distinctive personality traits and discrimination learning. Stability in the personality trait boldness was found to have an impact on learning performance in a visual reversal-learning task, with less bold goats performing better than bolder ones. These results support the general hypothesis that proactive animals tend to stick to once-learned routines and to react less flexibly to changing stimulus combinations (7). To study cooperative behavior in pigs, Rault et al. developed an ecologically relevant feeding paradigm, the so-called “joint log-lift task”. To complete the task, two pigs must cooperate in lifting a log to receive a reward. While kinship had no influence on the cooperation behavior of individual dyads, inter-individual differences in sociability influenced the willingness to cooperate in pigs. The relationship between social competence and the impact of intranasal oxytocin on social behavior of dogs was studied by Turcsán et al. While oxytocin has been reported to have a general positive effect on social behavior, intranasal administration of oxytocin in this study increased social behavior in dogs toward humans only in animals that showed already a low baseline performance of interacting with humans. This indicates that the effect of oxytocin on social behavior is dependent on personality traits and the specific context. A study by Brucks et al. investigated self-control in horses. They found that horses wait until a maximum delay of 60 s to receive a highly valued reward rather than to get an immediately available reward of lower quality. While horses fed hay ad libitum instead of receiving a restricted diet achieved higher delay times, the trainability or patience of the horses had no influence on the maximum delay level. Two of the submitted studies aimed to establish a relationship between different genetic predispositions and learning performance or flexibility in learning behavior. To test whether animals bred for high productivity have lower learning performance, Nawroth et al. compared the performance of dwarf goats and dairy goats in a visual discrimination and reversal-learning task. The results suggest that selection for high performance may have negatively affected the goats' behavioral flexibility with dwarf goats outperforming dairy goats in reversal learning. Dudde et al. investigated the role of the serotonin transporter (5-HTT) on anxiety and learning performance in chicken. Chicken from selection lines with different 5-HTT polymorphisms were tested with regard to their fearfulness and performance in a simple discrimination task. Chicken with reduced 5-HTT expression showed increased anxiety-like behavior, as has also been demonstrated in humans. However, and in contrast to human research, animals with reduced 5-HTT expression were also the slowest learners compared to hens with moderate or high...
Frontiers in Veterinary Science, Volume 9; https://doi.org/10.3389/fvets.2022.909401
Introduction: Piglet facial and sow teat lesions are the main reported reasons why pig producers routinely practice teeth resection. This is a painful procedure performed on piglets, where their needle teeth are clipped or ground to resect the pointed tip. The practice raises welfare concerns. In contrast to other procedures, such as tail docking, we know little about the risk factors for these two types of lesions.Methods: We employed two methods to answer these questions: (1) reviewing the literature to identify potential risk factors, and (2) surveying pig production stakeholders worldwide to identify the occurrence of these lesions and the strategies used in practice that enable pig producers to manage or prevent these lesions while avoiding teeth resection. For the literature review, we used Google Scholar to include peer-reviewed publications and gray literature. We distributed the survey using convenience sampling and documented information on the current situation regarding teeth resection, including the methods, frequencies, and reasons for resecting piglets' teeth, the occurrence of piglet facial and sow teat lesions, and measures used to prevent and control these lesions.Results: The literature review identified six major risk factors for both lesions, including the presence or absence of teeth resection, housing system, litter size, piglet management, environmental enrichment, milk production and other piglet management practices. However, most studies focused on the effects of the first two factors with very few studies investigating the other risk factors. There were 75 responses to the survey from 17 countries. The survey showed that half of the respondents practiced teeth resection with many recognizing that facial and teat lesions are the main reasons behind this practice. However, many producers used other interventions rather than teeth resection to prevent these lesions. These interventions focused on improving milk production of the sow, managing large litters, and providing environmental enrichment.Discussion: More research is needed to validate these interventions and more science-based advice is needed to bridge the gap between research and practice to help more producers further understand the cause of piglet facial and sow teat lesions to transition toward the cessation of routine teeth resection.