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Leptin regulates body weight and several physiological processes including reproduction. We evaluated the circulating levels of leptin in pregnant and non-pregnant bitches as well as their correlation with body weight, food intake and number of foetuses. Nineteen healthy German shepherd bitches were used and divided in two groups (pregnant n = 12 and non-pregnant n = 7). Blood samples were collected every 15 days starting from ovulation (Day 0) throughout pregnancy (pregnant group, P) or throughout luteal phase (non-pregnant group, NP) In pregnant bitches, leptin concentrations increased from the day of ovulation (1.32 ± 0.06 ng/ml) up to day 45 (1.51 ± 0.06 ng/ml; p < .01) and returned to baseline values from day 60 post-ovulation. In non-pregnant bitches, leptin concentrations remained constant throughout the whole observation period (estimated marginal mean ± SE=1.33 ± 0.38 ng/ml). Pairwise comparisons showed significant differences between P and NP at day 45 post-ovulation (p < .05). Multivariable models indicated that, controlling for time and litter size, there was a positive relationship between leptin concentration and BW (p < .05) although Pearson coefficients showed that the correlation between BW and leptin was only significant in NP animals at day 45 (r = 0.76, p < .05). The multivariable approach also suggested that, holding BW and time constant, leptin concentrations tend to increase as the number of puppies increased (p = .06). Our study supports indirectly the contribution of the feto-placental unit to the circulating maternal leptin concentration., (© 2020 Blackwell Verlag GmbH.)

Despite promising immunotherapy strategies in human melanoma, there are few studies on the immune environment of canine melanocytic tumors. In humans, the activation of immunosuppressive cell subpopulations, such as regulatory T cells (Tregs) that express forkhead box protein P3 (FoxP3), the engagement of immunosuppressive surface receptors like cytotoxic T lymphocyte antigen (CTLA-4), and the secretion of molecules inhibiting lymphocyte activation, such as indoleamine-pyrrole 2,3-dioxygenase (IDO), are recognized as immunoescape mechanisms that allow tumor growth and progression. The aim of our study was to investigate the expression of these immunosuppression markers in canine melanocytic tumors and to postulate their possible role in melanoma biology and progression. Fifty-five formalin-fixed, paraffin-embedded canine melanocytic tumors (25 oral melanomas; 20 cutaneous melanomas; 10 cutaneous melanocytomas) were selected to investigate the expression of FoxP3, CTLA-4, and IDO by immunohistochemistry and RT-qPCR (real-time quantitative polymerase chain reaction). All of the tested markers showed high gene and protein expression in oral melanomas and were differently expressed in cutaneous melanomas when compared to their benign counterpart. IDO expression was associated with an increased hazard of death both in univariable and multivariable analyses (P <.05). FoxP3 protein expression >6.9 cells/HPF (high-power field) was an independent predictor of death (P <.05). CTLA-4 gene and protein expressions were associated with a worse prognosis, but only in the univariable analysis (P <.05). FoxP3, CTLA-4, and IDO likely play a role in canine melanoma immunoescape. Their expression, if supported by future studies, could represent a prognostic tool in canine melanoma and pave the way to future immunotherapeutic approaches in dogs. [ABSTRACT FROM AUTHOR]

The study of the immune response in several types of tumours has been rapidly increasing in recent years with the dual aim of understanding the interactions between neoplastic and immune cells and their importance in cancer pathogenesis and progression, as well as identifying targets for cancer immunotherapy. Despite being considered one of the most immunogenic tumour types, melanoma can progress in the presence of abundant lymphocytic infiltration, therefore suggesting that the immune response is not able to efficiently control tumour growth. The purpose of this study was to investigate whether the density, distribution and grade of tumour‐infiltrating lymphocytes (TILs) in 97 canine melanocytic tumours is associated with histologic indicators of malignancy and can be considered a prognostic factor in the dog. As a further step in the characterization of the immune response in melanocytic tumours, an immunohistochemical investigation was performed to evaluate the two main populations of TILs, T‐lymphocytes (CD3+) and B‐lymphocytes (CD20+). The results of our study show that TILs are present in a large proportion of canine melanocytic tumours, especially in oral melanomas, and that the infiltrate is usually mild. The quantity of CD20+ TILs was significantly associated with some histologic prognostic factors, such as the mitotic count, the cellular pleomorphism and the percentage of pigmented cells. Remarkably, a high infiltration of CD20+ TILs was associated with tumour‐related death, presence of metastasis/recurrence, shorter overall and disease‐free survival, increased hazard of death and of developing recurrence/metastasis, hence representing a potential new negative prognostic factor in canine melanocytic tumours. [ABSTRACT FROM AUTHOR]

Although popular culture describes them as mortal enemies, more and more often, dogs and cats live under the same roof. Does this make them best friends? Can sharing the same social and physical environment make them similar? This study compares the approaches of dogs and cats living in the same household have towards humans and other pets as perceived by the owner. Questionnaires collected from 1270 people owning both dog(s) and cat(s) were analysed. Most dogs and cats living together are playful with familiar humans (76.2%) but dogs have a more sociable approach towards strangers and conspecifics than cats (P<0.001). Moreover, the percentage of dogs that have a playful relationship with the owner (84.0%) was higher than cats (49.2%; P<0.001). Dogs and cats living together eat in different places and show different mutual interactions: more dogs lick the cat (42.8%) and more cats ignore the dog (41.8%) than vice versa (P<0.001). However, most dogs and cats sleep at least occasionally (68.5%) and play together (62.4%; P<0.001). Although some body postures, such as the tail's position, are interpreted differently by the two species, the greater proportions of dogs and cats show a relaxed response to several kinds of approaches of their roommate. Our questionnaire confirms the common beliefs about the sociability of the dog and the privacy of the cat, but this does not result in continuous internal struggles. Most cohabitations are peaceful. Moreover, it is true that they speak different languages, but they seem to understand each other well and interpret each other's approaches in the right way. Thus, aspiring owners should not blindly believe popular assumptions, but both knowledge and respect for species-specific pet behaviours are essential to establish a balance in the household. [ABSTRACT FROM AUTHOR]

A high standard of physical fitness is an essential characteristic of drug detection dogs because it affects not only their ability to sustain high activity levels but also their attention and olfaction efficiency. Nutritional supplements could improve physical fitness by modulating energy metabolism, oxidative processes, and perceived fatigue. The aim of this study was to investigate the physiological and biochemical changes induced by submaximal exercise on drug detection dogs (German Shepherd breed) and to assess whether a dietary supplement improves their physical fitness. During a drug detection dog training course, seven dogs were fed with a basal diet (Control Group) for three-month period, while a further seven dogs were fed with a basal diet as well as a daily nutritional supplement containing branched-chain and limiting amino acids, carnitine, vitamins, and octacosanol (Treatment Group). At the end of this period, individual physical fitness was assessed by making each subject take a graded treadmill exercise test. A human heart rate monitor system was used to record the dog’s heart rate (HR) during the treadmill exercise and the subsequent recovery period. The parameters related to HR were analysed using nonparametric statistics. Blood samples were collected before starting the nutritional supplement treatment, before and after the treadmill exercise and following recovery. Linear mixed models were used. The dietary supplements accelerated HR recovery, as demonstrated by the lower HR after recovery (P<0.05) and Time constants of HR decay (P<0.05), and by the higher Absolute HR Recovered (P<0.05) recorded in the Treatment group compared with the Control dogs. The supplemented dogs showed the lowest concentrations of creatine kinase (CK; P<0.001), aspartate aminotransferase (AST, P<0.05) and non-esterified fatty acids (NEFA; P<0.01) suggesting a reduction in muscle damage and improvement of energy metabolism. These data suggest that this combined supplement can significantly enhance the physical fitness of drug detection dogs. [ABSTRACT FROM AUTHOR]

Highlights • A fast and straightforward welfare assessment system for shelter dogs was developed. • Qualitative assessments of Veterinary Officer were functional and consistent. • Dog's behaviour during the capture was the most problematic to define and evaluate. • Behavioural evaluations could improve management and welfare of shelter dogs. Abstract This study aimed to develop and validate a fast and straightforward welfare assessment system to help shelter staff in decision-making processes. For newly captured dogs entering the shelter, the animal control officer (at capture time) and the veterinary officer (at entrance examination) compiled a form attributing a qualitative score for the overall Stress level and for 5 Descriptors of dog behavioural traits. Furthermore, a tester filled out the same form by subjecting the dog to a test battery in his pen, besides performing behavioural observations. The veterinary officer and the tester repeated the evaluation protocol after four weeks of acclimatisation in the shelter. The analysis evaluated inter-observer and test–retest reliability, internal consistency, and construct validity of qualitative scores. Overall, we collected 258 forms regarding 189 dogs. Principal component (PC) extracted by Descriptors showed a good correlation with the Stress level score for veterinary and tester confirming the internal consistency of these scales while it was low for animal control officer form. Moreover, qualitative evaluations of the veterinarian and the tester showed congruent correlations with behavioural observations supporting their construct validity. Conversely, the scores expressed by the animal control officer were not consistent with quantitative observations. Then, the veterinary officer and tester forms could be validated and further simplified including only Stress level score while the control officer form requires a revision as it does not seem reliable. We did not find agreement between the Stress level scores expressed by animal control officer, veterinary and tester suggesting that the three contexts represent different stress stimuli to which the same dog reacts differently. The point of view of the three evaluators can increase the reliability of the assessment. Static but vigilant behaviours prevailed in newly sheltered dogs but activity, interactions and behavioural diversity increased in the second behavioural observation when the dogs were kept in multiple cages and four weeks of adaptation had passed. Stress level reduced and PCs tended towards the pole of sociability suggesting a reduction of stress after the period of adaptation to the socio-environmental conditions of the shelter. On the other hand, the considerable inter-individual variability in behaviours reflects differences in coping strategies and or in the manifestation of stress. Our simple tool can not replace a multidisciplinary approach to welfare assessment but could help shelter staff for individual management of dogs complying with their different adaptation skills. [ABSTRACT FROM AUTHOR]

Breslow thickness and Clark level are prognostic factors for human cutaneous melanomas. Breslow thickness is measured with an ocular micrometer from the top of the granular layer of the epidermis to the deepest invasive cell across the broad base of the tumor, while Clark level is based on the anatomical level of invasion through the layers of the dermis. Because of the anatomical differences between humans and dogs, we evaluated the tumor thickness and a modified Clark level in 77 canine primary cutaneous melanocytic tumors. Tumor thickness (using both a traditional and a more convenient system) and modified Clark level were measured and associated with histological diagnosis and clinical outcome. Tumor thickness was a prognostic factor, being greater in animals with shorter overall survival and disease-free time. Cutoffs of 0.95 cm and 0.75 cm defined a higher hazard for an unfavorable outcome and to develop recurrence/metastasis, respectively. Because of an excellent agreement between the 2 methods, it was concluded that tumor thickness could be measured with a ruler when an ocular micrometer is not available. Modified Clark level was not found to be relevant for prognosis. However, we suggest that both tumor thickness and a modified Clark level can be valid additional parameters when histological diagnosis is uncertain. Further studies, including a wider sample population, would be worthwhile to confirm the prognostic significance of these 2 parameters. [ABSTRACT FROM AUTHOR]

This study aims to define the personality traits perceived by the owners of multiple pets and to evaluate how they are modulated by experiential-environmental factors. A questionnaire was administered to 1270 owners of multiple pets (dogs and cats) to collect data on the demographics, management, and personality of their pets. Data were analysed by principal component analysis, bivariate, and multivariable models. Five personality traits emerged in dogs and cats: sociability, reactivity, protectiveness, neuroticism, and fearfulness. The owners perceived differences in the personality of their pet: dogs scored higher in sociability, protectiveness, and reactivity, while lower in the neuroticism dimension compared with cats (p < 0.001). Age similarly affected sociability (p < 0.01), and reactivity (p < 0.001) in both dogs and cats, while species-specific gender differences were found as to fearfulness (p < 0.05) and neuroticism (p < 0.001). The age of acquisition modulated several traits in dog personality, while living with conspecifics especially influenced cats. Physiological, behavioural, and evolutionary characteristics could explain species differences. Moreover, intrinsic and extrinsic factors modulated the five dimensions of dogs and cats in a diversified fashion, suggesting complex interactions between species and the environment. However, owners could have had different attitudes with their animals which could have influenced personality perception. [ABSTRACT FROM AUTHOR]

Avalanche search dogs are valuable resources in the event of environmental disasters. The aim of this study was to determine whether dog search strategies and dynamics of interaction with his handler influence team performance during a simulated avalanche search trial. This consisted in discovering a warm scented article, buried under the snow (−20 cm), within a specific space and time frame (10 min). Twelve dog-handler teams were enrolled in the trial. The dogs’ behaviour and dog-handler dynamics of interaction were video recorded and analysed using continuous focal animal sampling. The success of the trial was significantly related to the team (P < 0.05). A negative relationship was observed between team performance and the time the dogs spent standing (odds ratio: OR = 0.66, P < 0.05), gazing at the handler (OR = 0.85, P < 0.05) or touching him (OR = 0.55, P < 0.05). Conversely, during successful trials the dogs spent more time exploring sniffing (OR = 1.80, P < 0.001) and digging intensively (OR = 3.19, P < 0.05) than during unsuccessful trials. Two principal components (PCs) were extracted. The “Dog ’ s coping style” PC described the strategy applied during the search. Traits scoring high in the “Dog ’ s coping style” PC indicated exploratory behaviours and a proactive strategy, while reduced locomotor activity and handler-directed behaviours had negative loadings reflecting the passive coping style of the dog. The “Dog ’ s coping style” PC predicted the outcome of the trial per se (unadjusted OR: UOR Dog = 26.51, P < 0.05). The dynamics of interaction established between the dog and the handler during the search was described by the “Dog-handler relationship ” PC. A high score in the “Dog-handler relationship ” PC indicated the independent attitude of the dog and the close attention paid to the dog by his handler. The “Dog-handler relationship ” PC became a predictor of success controlling the “Dog ’ s coping style” PC, as shown by the adjusted OR (AOR Dog-handler = 3.49, P < 0.05). These findings suggest that a canine proactive strategy and high level of autonomy improve the performance of avalanche dogs. However, a dog’s independence does not preclude his ability to perceive the attentional state of the handler that may act as a positive reinforcement. [ABSTRACT FROM AUTHOR]

Simple Summary: Search and rescue (SAR) dogs are irreplaceable support in natural disasters. Not only are these animals required to have optimal scenting capabilities, but they are also required to have excellent physical conditions. Implementing protocols to monitor their fitness would help to optimize their performance and welfare. This study evaluated heart rate (HR) changes in avalanche SAR dogs and handlers during a 5.5 km endurance exercise in the snow, at an altitude of approximately 2000 m.a.s.l., reflecting their usual working and workload conditions. Dogs' and handlers' HR and activities were monitored by a global positioning satellite (GPS)/HR system. Factors influencing dogs' and handlers' HR changes and their possible correlation were investigated. As expected, the dog's HR changes during the endurance activity were affected by speed, gradient, altitude, and time. The handlers' HR changes differed and were not correlated with those recorded in the dogs. Thus, SAR handlers may not perceive the physical stress of their dog in real-time. Findings indicate that GPS/HR monitoring systems could be utilized in field conditions for monitoring SAR units' physical fitness. A "fitness index" could be developed by incorporating HR and velocity measurements in order to target training strategies and indicate risk factors for physical distress in working dogs. This study aimed to assess the heart rate (HR) responses of avalanche SAR dogs and handlers under working field conditions. Thirteen SAR units (dogs and handlers) performed an exercise (Endurance) consisting of approximately 5.5 km of rough tracks through deep snow, at an altitude of 1991–2250 m.a.s.l. The exercise was repeated twice for each of the two different tracks. Both handlers and dogs were equipped with a global positioning satellite/heart rate (GPS/HR) system (Polar®). Multivariable models were used to evaluate the effects of environmental (i.e., gradient, altitude, track, and time) and intrinsic (i.e., speed, repetition, and breed) factors on changes from baseline HR (Δ%HR). The dog's Δ%HR was greater in the flat and uphill compared with downhill, and increased progressively as the speed increased (p < 0.001). Moreover, it rose at altitudes above 2100 m.a.s.l. and peaked after 30 min of the Endurance activity (p < 0.01). These findings indicated that HR monitors could be a valuable tool to contribute to the evaluation of avalanche dogs' fitness in their real working environment. In contrast, the lack of correlation between the dogs' and handlers' HR changes suggests that handlers might not perceive the physical conditions of their dog in real-time. Thus, implementing protocols to monitor avalanche SAR dogs' fitness using a GPS/HR monitoring system could help handlers to tailor the training and workload and to detect the risk factors for physical distress of working dogs. [ABSTRACT FROM AUTHOR]

Simple Summary: In "no-kill policy" countries, many dogs live in shelters. Several social, environmental, and management challenges can put the welfare of shelter dogs at risk. More knowledge is still needed on how to assess shelter dog welfare. This study aimed to evaluate the state of welfare of a group of dogs entering a shelter using physiological and immunological parameters by exploring the value of some biological indicators obtained by non-invasive methods. Considering that early welfare assessment could improve the management of subjects more prone to developing distress, measurements were taken at the time of admission and four weeks after the dogs entered the shelter. A multivariate statistical approach was used to comprehensively evaluate the relationship between the variables investigated. A reduction in the values of the measured physiological and immune parameters over time suggested an improvement in the dogs' welfare after four weeks of being in the shelter compared to the initial capture and admission time. Findings also highlighted that some of the parameters investigated, such as neutrophils, lymphocytes, and fecal cortisol and lysozyme could be used for the welfare assessment of dogs entering a shelter. This study aimed to evaluate the state of welfare of a group of dogs during the first month after entering the shelter by using different stress parameters. Blood and fecal samples were collected from a group of 71 dogs at the time of admission to the shelter. In 46 of these dogs, sampling was repeated after four weeks. Well-recognized welfare biomarkers, such as fecal cortisol and leukocytes, as well as some innovative parameters (β-endorphin and lysozyme) were determined. Uni- and multivariate statistical analyses were used to evaluate their interactions and changes over time. Neutrophils (p < 0.01), lysozyme (p < 0.05), and fecal cortisol (p < 0.05) decreased, while lymphocytes (p < 0.05) increased after four weeks compared to the first days of being in the shelter, suggesting an improvement in the dogs' welfare over time. A principal component analysis extracted three bipolar components (PCs), explaining 75% of the variance and indicating negative associations between neutrophil and lymphocyte (PC1), lysozyme and β-endorphin (PC2), cortisol and lysozyme (PC3). The associations between these variables within each PC also confirmed the intricate relationships between the hypothalamic-pituitary-adrenal (HPA) axis and the immune system as well as the importance of a multiparametric approach in evaluating welfare. [ABSTRACT FROM AUTHOR]