In "Tone" with dogs: exploring canine musicality.

This study investigates the musical perception skills of dogs through playback experiments. Dogs were trained to distinguish between two different target locations based on a sequence of four ascending or descending notes. A total of 16 dogs of different breeds, age, and sex, but all of them with at least basic training, were recruited for the study. Dogs received training from their respective owners in a suitable environment within their familiar home settings. The training sequence consisted of notes [Do-Mi-Sol#-Do (C7-E7-G7#-C8; Hz frequency: 2093, 2639, 3322, 4186)] digitally generated as pure sinusoidal tones. The training protocol comprised 3 sequential training levels, with each level consisting of 4 sessions with a minimum of 10 trials per session. In the test phase, the sequence was transposed to evaluate whether dogs used relative pitch when identifying the sequences. A correct response by the dog was recorded as 1, while an incorrect response, occurring when the dog chose the opposite zone of the bowl, was marked as 0. Statistical analyses were performed using a binomial test. Among 16 dogs, only two consistently performed above the chance level, demonstrating the ability to recognize relative pitch, even with transposed sequences. This study suggests that dogs may have the ability to attend to relative pitch, a critical aspect of human musicality.

Human social buffer in goats and dogs.

The primary goal of this study was to explore the social buffering effect that humans offer to goats and dogs with limited exposure to human socialization, particularly in situations involving interactions with unfamiliar humans. A total of 13 dogs and 14 goats were selected for the study, all of which had limited prior socialization with humans. Each animal was placed in a testing room with unfamiliar humans for 15 min. Three experimenters aimed to establish a comfortable environment, encouraging social interaction by offering food to the animals and assessing the animals' willingness to accept food and their response to being approached and petted. If both conditions were satisfied, the animals were classified as "social". If one or none of the conditions were met, the animals were classified as "not social". Cortisol levels were measured by collecting blood samples before and after the test. Non-parametric tests together with a GzLM showed that the effect of human social buffering in goats was different in comparison to dogs: goats exhibited higher cortisol levels after the test, while dogs did not show a significant change. Further analysis demonstrated that "social" goats had a lower likelihood of experiencing significant changes in cortisol levels than dogs. Thus, once human interactions are accepted, both species could benefit from social buffering. In summary, this study enhances our understanding of how dogs and goats respond to social interactions with humans in the social buffering effect.

A Comparative Study of Dogs and Goats with Limited Human Socialization in the Impossible Task Paradigm.

The study aimed to explore how limited human socialization affects the socio-cognitive abilities and interactions with unfamiliar individuals of a selected group of domesticated dogs and goats. These animals were raised and kept under conditions characterized by limited human socialization, and their behavior was assessed using the "impossible task" paradigm. The study found that dogs, with a history of cooperative interactions and human companionship, exhibited more frequent social engagement with human experimenters in the experimental setting than goats, traditionally domesticated for utilitarian purposes. However, differences in interaction duration and latency were not significant, highlighting the complexity of these interactions. The results suggest that domestication history and behavioral ecology play significant roles in shaping animals' willingness to engage with humans. However, this study acknowledges limitations, such as the specific population studied, and calls for further research with larger and more diverse samples to generalize these findings. Understanding the interplay between domestication history, behavioral ecology, and human socialization could provide insights into the complex factors influencing animal-human interactions and cognitive behaviors, with implications for animal welfare and human-animal relationships.

Home Sweet Home: The Impact of Lifestyle on a Cat's Approach to Impossible Tasks in the Home Environment.

Cat welfare is a topic of growing interest in the scientific literature. Although previous studies have focused on the effects of living style (i.e., indoor/outdoor) on cat welfare, there has been a noticeable dearth of analysis regarding the impact of lifestyle on cats' inclination and mode of communication with humans. Our research aimed to analyze the possible effect of lifestyle (e.g., living indoors only or indoor/outdoor) on cat-human communication. The cats were tested using the impossible task paradigm test, which consists of some solvable trials in which the subject learns to obtain a reward from an apparatus, followed by an impossible trial through blocking the apparatus. This procedure triggers a violation of expectations and is considered a useful tool for assessing both the decision-making process and the tendency to engage in social behaviors towards humans. A specific ethogram was followed to record the behavioral responses of the cats during the unsolvable trial. Our results show the effects of lifestyle and age on domestic cats, providing valuable insights into the factors that influence their social behaviors. Cats that can roam freely outdoors spent less time interacting with the apparatus compared to indoor-only cats. Additionally, roaming cats showed stress behaviors sooner following the expectancy of violation compared to indoor cats. The lifestyle of cats can influence their problem-solving approach while not affecting their willingness to interact with humans or their overall welfare. Future studies on this topic can be useful for improving the welfare of domestic cats.

When are puppies receptive to emotion-induced human chemosignals? The cases of fear and happiness.

We report an observational, double-blind, experimental study that examines the effects of human emotional odors on puppies between 3 and 6 months and adult dogs (one year and upwards). Both groups were exposed to control, human fear, and happiness odors in a between subjects' design. The duration of all behaviors directed to the apparatus, the door, the owner, a stranger, and stress behaviors was recorded. A discriminant analysis showed that the fear odor activates consistent behavior patterns for both puppies and adult dogs. However, no behavioral differences between the control and happiness odor conditions were found in the case of puppies. In contrast, adult dogs reveal distinctive patterns for all three odor conditions. We argue that responses to human fear chemosignals systematically influence the behaviors displayed by puppies and adult dogs, which could be genetically prefigured. In contrast, the effects of happiness odors constitute cues that require learning during early socialization processes, which yield consistent patterns only in adulthood.

Serum Oxytocin, Cortisol and Social Behavior in Calves: A Study in the Impossible Task Paradigm.

In this study, we explored the correlations between circulating levels of oxytocin, cortisol, and different social behaviors toward humans in 26 Italian Red Pied calves (all females, with an average age of 174 ± 24 days) using the impossible task paradigm. This paradigm has proved fruitful in highlighting the effect of socialization on the willingness to interact with humans in several domesticated species. The test consists of the violation of an expectation (recovering food from an experimental apparatus) while a caregiver and a stranger are present. Immediately after the end of the test (less than one minute), blood was collected from the coccygeal vein. Statistics were performed by the Spearman's rank correlation; significant differences were adjusted according to Bonferroni's correction. Cortisol correlates positively (ρ = 0.565; p < 0.05) with the latency of behaviors directed at the caregiver, and the duration of behaviors directed at the apparatus correlates negatively with both the caregiver (ρ = -0.654; p < 0.05) and a stranger (ρ = -0.644; p < 0.05). Contrary to what is reported in the literature on cows, no correlations were found between oxytocin levels and direct behaviors toward the caregiver. This highlights a different behavioral strategy between calves and cows when placed in front of an impossible task.

The Begging Strategy of Andean Dogs: An Exploratory Study.

In this study, we report a particular begging strategy by Andean dogs and by humans on the unsurfaced road between the villages of Parotani and Cahiuasi in Bolivia. The positions of the dogs and humans begging and their behavioral displays were recorded. In dogs, the distance from each other was also recorded. Begging locations, for both dogs and humans, were permuted with a score, according to the higher probability of receiving food. The highest scores were assigned to the positions where cars had to slow down and the subjects were well visible, thus meriting a score corresponding to the higher probability of receiving a treat. The occurrences of the correct positioning at the external and internal parts of the bend were compared by a chi-square test. On a range of 93.3 km, the dogs were observed to always lie down at the border of the road, mainly alone (96.3%) and on hairpin bends, present due to the steep slope, obliging the vehicles to slow down. Humans were observed mainly in groups. The percentage of dogs lying on the external part of the bends was 81.2%, which was above the level of chance (p < 0.01). Humans were observed at external bends in 63.6% of cases, which was at chance level. Begging locations, for both dogs and humans, were permuted with a score according to the higher probability of receiving food. The mean scores were 1.48 and 0.65 for dogs and humans, respectively, and the difference was highly significant (p < 0.001).

Puppies in the problem-solving paradigm: quick males and social females.

We report an observational, double-blind study that examined puppies' behaviors while engaged in solving an experimental food retrieval task (food retrieval task instrument: FRTI). The experimental setting included passive social distractors (i.e., the dog's owner and a stranger). The focus was on how the social and physical environment shapes puppies' behaviors according to sex. The dependent variables were the number of tasks solved on an apparatus (Performance Index) and the time required to solve the first task (Speed). Sex and Stress were set as explanatory factors, and Social Interest, FRTI interactions, other behavior, and age as covariates. The main findings were that male puppies solved the first task faster than females. On the other hand, females displayed significantly more social interest and did so more rapidly than males. Males showed delayed task resolution. This study demonstrates sex differences in a problem-solving task in dog puppies for the first time, thus highlighting that sexually dimorphic behavioral differences in problem-solving strategies develop early on during ontogenesis.

Can Humans Discriminate Horse 'Fear' Chemosignals from Control Chemosignals? Comment on Sabiniewicz et al. A Preliminary Investigation of Interspecific Chemosensory Communication of Emotions: Can Humans (Homo sapiens) Recognise Fear- and Non-Fear Body Odour from Horses (Equus ferus caballus). Animals 2021, 11, 3499.

We illustrate the problematic nature of different assumptions guiding the examination of whether humans can detect the source of fear chemosignals (i.e., body odors) emitted by horses-a research question examined in an article recently published in Animals. A central issue is that the formulation of the question itself contains the answer to it. In this paper, we parse the problematic assumptions on which the analysis and methodology rely, leading to conclusions that are difficult to support. These assumptions constitute examples of methodological problems that should be avoided in research with animals and odors. The unique aspect of this paper is that it is a collaborative product, including the original contributor, in the pursuit of transparency in science.

Comparative insights of the neuroanatomical distribution of the gonadotropin-inhibitory hormone (GnIH) in fish and amphibians.

This paper intends to apprise the reader regarding the existing knowledge on the neuroanatomical distribution of GnIH-like peptides in in fish and amphibians in both the adult stage and during ontogenesis. The neuroanatomical distribution of GnIH-like neuropeptides appears quite different in the studied species, irrespective of the evolutionary closeness. The topology of the olfactory bulbs can affect the distribution of neurons producing the GnIH-like peptides, with a tendency to show a more extended distribution into the brains with pedunculate olfactory bulbs. Therefore, the variability of the GnIH-like system could also reflect specific adaptations rather than evolutionary patterns. The onset of GnIH expression was detected very early during development suggesting its precocious roles, and the neuroanatomical distribution of GnIH-like elements showed a generally increasing trend. This review highlights some critical technical aspects and the need to increase the number of species to be studied to obtain a complete neuroanatomical picture of the GnIH-like system.

Effects of Linseed Supplementation on Milk Production, Composition, Odd- and Branched-Chain Fatty Acids, and on Serum Biochemistry in Cilentana Grazing Goats.

The purpose of this study was to investigate the effects of linseed supplementation on milk yield and quality, serum biochemistry and, in particular, to evaluate its possible effects on the production of odd- and branched-chain fatty acids (OBCFA) in the milk of Cilentana grazing goats. Twelve pregnant Cilentana dairy goats were divided into two groups (CTR, control, and LIN, linseed supplementation group). After kidding, the goats had free access to the pasture and both groups received a supplement of 400 g/head of concentrate, but the one administered to the LIN group was characterized by the addition of linseed (in a ratio of 20% as fed) to the ingredients. During the trial, milk samples were taken from April to August in order to evaluate milk production, composition, and fatty acid profile. In addition, blood samples were taken for evaluating the effects of linseed supplementation on goats' health status. The health status of the goats was not influenced by the linseed supplementation, as confirmed by blood analyses. Concerning the effects on milk, the supplementation positively affected (p < 0.001) milk production and fat percentage and the fatty acid profile was markedly influenced by the lipid supplementation. In particular, milk from the LIN group was characterized by significantly lower concentrations of saturated fatty acids (FA; p < 0.001) and higher proportions of monounsaturated FA, polyunsaturated FA, and conjugated linoleic acids (CLAs) than milk from the CTR group (p < 0.001). In contrast, the OBCFA were negatively influenced by the linseed supplementation (p < 0.0001). Further studies are needed to test the effects of different fat sources and other nutrients on the diets.

Effects of a Nutritional Supplement (DìRelaxTM) on Anxiety in Dogs in a Randomized Control Trial Design.

This study aimed to investigate the efficacy of DìRelaxTM, a nutraceutical formulated to reduce anxiety in dogs, using a randomized controlled trial (RCT) design. The C-BARQ questionnaire, some clinical investigations, and the impossible task test were performed in dogs before and after treatment. The C-BARQ questionnaire is particularly useful for assessing the frequency and severity of problematic behaviors. The impossible task paradigm provides insight into the decision-making processes in the realm of expectancy frustration. Results showed an ameliorative effect on the performances of treated dogs during the solvable phases, with a significant decrease in the time needed to solve the task. No behavioral difference was found between treated and untreated anxious dogs during the unsolvable phase. According to the results from the C-BARQ questionnaire, some of the behaviors appeared to improve. Clinical investigations, including a complete blood cell count and blood chemistry, showed no difference between groups, thus suggesting the safety of the product. In general, this study suggests that DìRelaxTM can be safely administered with no adverse effects and can exercise a beneficial effect on anxious dogs by enhancing their cognitive abilities, but further studies should investigate the best method of administration.

Serum Oxytocin in Cows Is Positively Correlated with Caregiver Interactions in the Impossible Task Paradigm.

This study explored a possible relationship between the circulating oxytocin, cortisol, and the willingness of dairy cows to engage in social behaviors with humans in an experimental context. The behaviors of twenty-nine cows were recorded during the impossible task paradigm, a procedure aimed at creating a violation of expectancy, in the presence of the caregiver and a stranger. The results showed that serum oxytocin levels were positively correlated with duration and negatively correlated with the latency of the cows' social interactions with the caregiver. This research provides a clear correlation between circulating oxytocin and a willingness to engage in social contact with the caregiver, excluding the possible effect of different cortisol levels on such behavior.

The differential role of Leydig cells in the skin and gills of Lissotriton italicus larvae.

Larval urodeles are provided with external gills involved, along with the skin, in gas exchange and osmoregulation. Gills and skin epithelia are different, each showing a peculiar set of specialized cells but both provided with Leydig cells (LCs). Information on LCs in the gills is lacking as the literature has focused primarily on the epidermis. Contradictory and fragmentary results highlight that LCs origin, fate, and functions remain not fully understood. Here, we investigated the morpho-functional differences of LCs in the skin and gills of Lissotriton italicus larvae for the first time. LCs showed the same morphological and ultrastructural features in both tissues, even if LCs were significantly larger in the epidermis. Despite the uniform morphology within the LCs population, the proliferative ability was different. The putative diversity in the mucus composition was evaluated using a panel of 4 lectins as markers of specific carbohydrate moieties, revealing that sites of specific glycoconjugates were comparable in two tissues. To disclose the involvement of LCs in water storage and transport, immunofluorescence assay for aquaporin-3 has also been performed, demonstrating the expression of this protein only in gills epithelium. By demonstrating that LCs can multiply by cell division in gills, our results will also contribute to the discussion about their proliferative ability. Finally, we found that the LCs cytoplasm is rich in glycoconjugates, which are involved in many diverse and essential functions in vertebrates. RESEARCH HIGHLIGHTS: In gills LCs can multiply by cell division and express aquaporin-3 demonstrating a tissue-specific role of LCs. LCs cytoplasm is rich in glycoconjugates. LCs population show a uniform morphology in both gills and skin.

Is this love? Sex differences in dog-owner attachment behavior suggest similarities with adult human bonds.

Sex differences in the behavioral responses of Labrador Retriever dogs in the Strange Situation Test were explored. Behaviors expressed by dogs during seven 3-min episodes were analyzed through a Principal Component Analysis (PCA). The scores of factors obtained were analyzed with a Generalized Linear Mixed Model to reveal the effects of the dog's sex and age and the owner's sex. In Episode 1 (dog and owner) and 5 (dog alone), the PCA identified three and two factors, respectively, which overall explained 68.7% and 59.8% of the variance, with no effect of sex. In Episodes 2 (dog, owner, and stranger), 3 and 6 (dog and stranger), and 4 and 7 (dog and owner), the PCA identified four factors, which overall explained 51.0% of the variance. Effects of sex were found on: Factor 1 (distress), with lower scores obtained by females in Episode 2 and higher in Episode 3; Factor 2 (sociability), which was overall higher in females; Factor 3 (separation-distress), with females, but not males, obtaining higher scores when left with the stranger than when with the owner. Therefore, females were overall more social but seemed more affected than males by the owner's absence. Parallels can be traced between our results and sex differences found in adult human romantic attachment, suggesting that the dog-owner bond has characteristics that are not found in the infant-mother relationship.

Effects of ecotrofin™ on milk yield, milk quality and serum biochemistry in lactating goats.

A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400 g/day of corn meal, and the treated group was supplemented with 20 g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30 days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega-6:omega-3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, p < 0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed.

Research Trends in Octopus Biological Studies.

Octopuses represent interesting model studies for different fields of scientific inquiry. The present study provides a bibliometric analysis on research trends in octopuses biological studies. The analysis was executed from January 1985 to December 2020 including scientific products reported in the Web of Science database. The period of study was split into two blocks ("earlier period" (EP): 1985-2010; "recent period" (RP): 2011-2020) to analyze the evolution of the research topics over time. All publications of interest were identified by using the following query: ((AK = octopus) OR (AB = octopus) OR (TI = octopus)). Data information was converted into an R-data frame using bibliometrix. Octopuses studies appeared in 360 different sources in EP, while they increased to 408 in RP. Sixty countries contributed to the octopuses studies in the EP, while they were 78 in the RP. The number of affiliations also increased between EP and RP, with 835 research centers involved in the EP and 1399 in the RP. In the EP 5 clusters (i.e., "growth and nutrition", "pollution impact", "morphology", "neurobiology", "biochemistry") were represented in a thematic map, according to their centrality and density ranking. In the RP the analysis identified 4 clusters (i.e., "growth and nutrition", "ecology", "pollution impact", "genes, behavior, and brain evolution"). The UK with Ireland, and the USA with Canada shared the highest number of publications in the EP, while in the RP, Spain and Portugal were the leading countries. The current data provide significant insight into the evolving trends in octopuses studies.

Sex differences in the behavioral responses of dogs exposed to human chemosignals of fear and happiness.

This research focuses on sex differences in the behavioral patterns of dogs when they are exposed to human chemosignals (sweat) produced in happy and fear contexts. No age, breed or apparatus-directed behavior differences were found. However, when exposed to fear chemosignals, dogs' behavior towards their owners, and their stress signals lasted longer when compared to being exposed to happiness as well as control chemosignals. In the happy odor condition, females, in contrast to males, displayed a significantly higher interest to the stranger compared to their owner. In the fear condition, dogs spent more time with their owner compared to the stranger. Behaviors directed towards the door, indicative of exit interest, had a longer duration in the fear condition than the other two conditions. Female dogs revealed a significantly longer door-directed behavior in the fear condition compared to the control condition. Overall the data shows that the effect of exposure to human emotional chemosignals is not sex dependent for behaviors related to the apparatus, the owner or the stress behaviors; however, in the happiness condition, females showed a stronger tendency to interact with the stranger.

The scholar's best friend: research trends in dog cognitive and behavioral studies.

In recent decades, cognitive and behavioral knowledge in dogs seems to have developed considerably, as deduced from the published peer-reviewed articles. However, to date, the worldwide trend of scientific research on dog cognition and behavior has never been explored using a bibliometric approach, while the evaluation of scientific research has increasingly become important in recent years. In this review, we compared the publication trend of the articles in the last 34 years on dogs' cognitive and behavioral science with those in the general category "Behavioral Science". We found that, after 2005, there has been a sharp increase in scientific publications on dogs. Therefore, the year 2005 has been used as "starting point" to perform an in-depth bibliometric analysis of the scientific activity in dog cognitive and behavioral studies. The period between 2006 and 2018 is taken as the study period, and a backward analysis was also carried out. The data analysis was performed using "bibliometrix", a new R-tool used for comprehensive science mapping analysis. We analyzed all information related to sources, countries, affiliations, co-occurrence network, thematic maps, collaboration network, and world map. The results scientifically support the common perception that dogs are attracting the interest of scholars much more now than before and more than the general trend in cognitive and behavioral studies. Both, the changes in research themes and new research themes, contributed to the increase in the scientific production on the cognitive and behavioral aspects of dogs. Our investigation may benefit the researchers interested in the field of cognitive and behavioral science in dogs, thus favoring future research work and promoting interdisciplinary collaborations.