scholarly journals Friendship or Competition? Symmetry in Social Play within the Two Packs of German Shepherd Puppies

Animals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1627
Author(s):  
Jana Kottferová ◽  
Lenka Skurková ◽  
Lýdia Mesarčová ◽  
Lenka Lešková ◽  
Alena Demeová ◽  
...  

The symmetry of social play in Canids has been previously studied, especially in wolves, free-ranging dogs, and within mixed-aged groups, however our study focused on symmetry and asymmetry within play interactions in two litters (14 puppies) of German Shepherd dogs (GSDs). At the age of 7 weeks, we evaluated 1287 dyadic interactions (litter 1: n = 339 interactions, litter 2: n = 948 interactions), and at the age of 9 weeks we evaluated 1255 dyadic interactions (litter 1: n = 433 interactions, litter 2: n = 822 interactions). Dyadic interactions were observed and the winning indexes were calculated for 43 pairs (dyads). The groups of puppies studied were all the same age, therefore we focused on the aspects of sex and body size as primary variables. The weight and chest circumference of all puppies were measured. The distribution of interactions showed a slight inclination to mixed-sex dyads, but we did not obtain any statistically significant results concerning the impact of body size on play interactions. Symmetry in play was observed within litter 1 at the age of 7 weeks and at the age of 9 weeks, and within litter 2 at the age of 7 weeks. Since the number of puppies in this study was too small, these results should be interpreted regarding this limitation, and cannot be generalized to a larger population of domestic dogs nor the GSD breed. In further studies, it would be interesting to compare larger samples of different breeds, under different breeding conditions, and the effect of the environment on the style of social play.

2017 ◽  
Vol 65 (5) ◽  
pp. 292 ◽  
Author(s):  
Bradley P. Smith ◽  
Teghan A. Lucas ◽  
Rachel M. Norris ◽  
Maciej Henneberg

Endocranial volume was measured in a large sample (n = 128) of free-ranging dingoes (Canis dingo) where body size was known. The brain/body size relationship in the dingoes was compared with populations of wild (Family Canidae) and domestic canids (Canis familiaris). Despite a great deal of variation among wild and domestic canids, the brain/body size of dingoes forms a tight cluster within the variation of domestic dogs. Like dogs, free-ranging dingoes have paedomorphic crania; however, dingoes have a larger brain and are more encephalised than most domestic breeds of dog. The dingo’s brain/body size relationship was similar to those of other mesopredators (medium-sized predators that typically prey on smaller animals), including the dhole (Cuon alpinus) and the coyote (Canis latrans). These findings have implications for the antiquity and classification of the dingo, as well as the impact of feralisation on brain size. At the same time, it highlights the difficulty in using brain/body size to distinguish wild and domestic canids.


1981 ◽  
Vol 59 (9) ◽  
pp. 1775-1783 ◽  
Author(s):  
Paul B. Latour

I observed 73 dyadic interactions (bouts) between adult male polar bears (> 6 years) at Cape Churchill, Manitoba, from 4 October to 9 November 1978. All bouts involved at least one marked bear. I classified these bouts as social play and in this paper I discuss the criteria used for this classification. Social play bouts were composed of discrete motor acts and showed some predictability and structure. Two bouting bears respond to one another in a predictable manner as indicated by the mutuality of initiator-receiver acts. Structuring was suggested by a major three-act sequence for both initiators and receivers. Aggressive acts were found to be characteristic of initiators; the less aggressive, withdrawing acts were characteristic of receivers. The results are interpreted from both the structuralist and functionalist approaches to social play. I hypothesize that social play between adult male polar bears during the noncompetitive period of their annual cycle serves as a socialization process facilitating both opponent assessment and the refinement of social interaction. Both of these are probably important at times of the year when intraspecific competition is more intense.


2021 ◽  
Author(s):  
Jared K. Wilson‐Aggarwal ◽  
Cecily E.D. Goodwin ◽  
Tchonfienet Moundai ◽  
Metinou K. Sidouin ◽  
George J.F. Swan ◽  
...  

2021 ◽  
Vol 11 (3) ◽  
pp. 344
Author(s):  
Kinga Gzielo ◽  
Agnieszka Potasiewicz ◽  
Ewa Litwa ◽  
Diana Piotrowska ◽  
Piotr Popik ◽  
...  

Prenatal maternal infection is associated with an increased risk of various neurodevelopmental disorders, including autism spectrum disorders (ASD). Maternal immune activation (MIA) can be experimentally induced by prenatal administration of polyinosinic:polycytidylic acid (poly I:C), a synthetic viral-like double-stranded RNA. Although this MIA model is adopted in many studies, social and communicative deficits, included in the first diagnostic criterion of ASD, are poorly described in the offspring of poly(I:C)-exposed dams. This study aimed to characterize the impact of prenatal poly(I:C) exposure on socio-communicative behaviors in adolescent rats. For this purpose, social play behavior was assessed in both males and females. We also analyzed quantitative and structural changes in ultrasonic vocalizations (USVs) emitted by rats during the play test. Deficits of social play behaviors were evident only in male rats. Males also emitted a significantly decreased number of USVs during social encounters. Prenatal poly(I:C) exposure also affected acoustic call parameters, as reflected by the increased peak frequencies. Additionally, repetitive behaviors were demonstrated in autistic-like animals regardless of sex. This study demonstrates that prenatal poly(I:C) exposure impairs socio-communicative functioning in adolescent rats. USVs may be a useful tool for identifying early autistic-like abnormalities.


2016 ◽  
Vol 201 ◽  
pp. 1-9 ◽  
Author(s):  
Izabela A. Wierzbowska ◽  
Magdalena Hędrzak ◽  
Barłomiej Popczyk ◽  
Henryk Okarma ◽  
Kevin R. Crooks

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chen-Chih Chen ◽  
Ai-Mei Chang ◽  
Ming-Shan Tsai ◽  
Yen-Hua Huang ◽  
Kurtis Jai-Chyi Pei ◽  
...  

AbstractSince 2013, a high incidence of bilateral symmetrical alopecia has been observed in free-ranging Formosan macaques (Macaca cyclopis) in Mt. Longevity, Taiwan. We hypothesized that stress induces alopecia in this population. To verify our hypothesis, we evaluated the histopathological characteristics of skin biopsy and used a validated enzyme immunoassay (EIA) for fecal glucocorticoid metabolite (FGM) analysis, which act as an indicator of stress experienced by the individual. Follicular densities were lower (2.1–3.0 mm2) in individuals with symmetrical alopecia than in those with normal hair conditions (4.7 mm2). Furthermore, anagen to catagen/telogen ratios were lower in individuals with alopecia (0–1.4) than in those with normal hair (4.0). The histopathological characteristics of alopecia were similar to those of telogen effluvium, which indicates that stress is one of the possible etiologies. On the basis of the analytical and biological validation of EIAs for FGM analysis, 11β-hydroxyetiocholanolone was considered suitable for monitoring adrenocortical activity in both sexes of Formosan macaques. The mean concentrations (standard error; sample size) of 11β-hydroxyetiocholanolone were 2.02 (0.17; n = 10) and 1.41 (0.10; n = 31) μg/g for individuals with and without alopecia, respectively. Furthermore, the results of logistic regression analysis show that 11β-hydroxyetiocholanolone (p = 0.012) concentration was positively associated with alopecia. Thus, stress was the most likely to trigger symmetrical alopecia in Formosan macaques in Mt. Longevity. Although stress can decrease the fitness of an individual, considering the population status of Formosan macaques in Taiwan is stable and alopecia was only observed in our study area, which is isolated from other populations, the impact on the total population of Formosan macaque in Taiwan is limited. Nonetheless, stress-induced immunosuppression and alopecia might affect the local abundance and increase zoonosis risk due to frequent human–macaque contact in Mt. Longevity. Future studies are suggested to focus on the causative factor of stress and the effects of stress and alopecia on the health and welfare in the Formosan macaques.


Zoo Biology ◽  
2009 ◽  
pp. n/a-n/a ◽  
Author(s):  
Julia Ritz ◽  
Catrin Hammer ◽  
Marcus Clauss
Keyword(s):  

2021 ◽  
pp. 229-244
Author(s):  
Sarah Cubaynes ◽  
Simon Galas ◽  
Myriam Richaud ◽  
Ana Sanz Aguilar ◽  
Roger Pradel ◽  
...  

Survival analyses are a key tool for demographers, ecologists, and evolutionary biologists. This chapter presents the most common methods and illustrates their use for species across the Tree of Life. It discusses the challenges associated with various types of survival data, how to model species with a complex life cycle, and includes the impact of environmental factors and individual heterogeneity. It covers the analysis of ‘known-fate’ data collected in lab conditions, using the Kaplan–Meier estimator and Cox’s proportional hazard regression analysis. Alternatively, survival data collected on free-ranging populations usually involve individuals missing at certain monitoring occasions and unknown time at death. The chapter provides an overview of capture–mark–recapture (CMR) models, from single-state to multi-state and multi-event models, and their use in animal and plant demography to estimate demographic parameters while correcting for imperfect detection of individuals. It discusses various inference frameworks available to implement CMR models using a frequentist or Bayesian approach. Only humans are an exception among free-ranging populations, with the existence of several consequent databases with perfect knowledge of age and cause of death for all individuals. The chapter presents an overview of the most common models used to describe mortality patterns over age and time using human mortality data. Throughout, focus is placed on eight case studies, which involve lab organisms, free-ranging animal populations, plant populations, and human populations. Each example includes data and codes, together with step-by-step guidance to run the survival analysis.


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