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Nature and nurture—How different conditions affect the behavior of dogs

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Abstract

Temperament tests for working dogs can provide substantial information about a particular dog's behavioral phenotype. When a larger proportion of the population is tested, the test results can also provide information about the effects of different environmental conditions on the phenotype because if the population is large, the social and physical environments to which the dogs are exposed differ. This means that we need to include in our evaluations the perspective that uses information about the environment in relation to the individual dog's level of development. There is substantial evidence that basic temperament traits in dogs are moderately heritable. There is also evidence that postweaning conditions have a huge effect on development, and this effect is often not assayed. Selective breeding for desired traits in combination with optimal environmental conditions, adapted to the individual dog's level of maturation, is a key point when producing outstanding working dogs.

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... The increased incidence of behavioural disorders in commercially bred dogs may be caused by a lack of appropriate stimulation during early life (Jagoe, 1994in Serpell & Jagoe, 1995. Thus, in addition to other major factors influencing behaviour, such as genetics (Houpt, 2007) and responsible ownership (Jagoe & Serpell, 1996), the early life experiences of the pup play a major role in its further behavioural development (Wilsson, 2016). While research on domestic dogs is scarce, studies on primates and rodents corroborate the importance of the early life phase in shaping the individual phenotype (Harlow et al., 1971;Sanchez et al., 2001). ...
... Like most altricial species, a new born dog pup is blind and deaf, and cognition and motor skills are poor due to the immaturity of the brain (Fox, 1971a). In this virtually isolated state, pups are highly dependent on their mother for nourishment, warmth, and elimination, the latter of which is stimulated through anogenital licking by the mother (Rheingold, 1963;Wilsson, 2016). From three weeks of age pups signal distress upon brief separation from the mother in the form of whining and yelping, which decreases in intensity with age (Elliot & Scott, 1961). ...
... The early or first socialisation period is followed by the late or second socialisation phase (Table 2), also called juvenile period in the literature. The late socialisation phase extends to approximately six months of age, when sexual maturity is reached (Scott, 1958;Case, 2005;Wilsson, 2016). Although considered less sensitive than the early socialisation period, the importance of the juvenile and succeeding adolescence period for further behavioural development has recently been discussed in rodents (Sachser et al., 2011;Brydges, 2016). ...
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Behavioural disorders are a major reason for euthanasia and sheltering of pet dogs. The prevention and treatment of behavioural disorders requires a better understanding of the underlying causes. Early life experiences, such as maternal care, attachment and socialisation, have long lasting and serious consequences for the behavioural and physiological development of an individual. The complex interplay between these factors is likely to have consequences for the future dog-owner bond and the vulnerability to develop behavioural disorders. Here, we summarise the current literature on the interactions between maternal care, attachment formation, and the sensitive socialisation period and their potential consequences on adult dog behaviour. Based on the findings we highlight gaps in knowledge and provide suggestions for future research which are necessary to formulate recommendations for pet dog breeding and socialisation.
... Like most altricial species, a newborn pup is blind and deaf, and cognition and motor skills are poor due to the immaturity of the brain (Fox, 1971). In this virtually-isolated state, pups are highly dependent on their mother for nourishment, warmth, and elimination, the latter of which is stimulated through anogenital licking by the mother (Rheingold, 1963;Wilsson, 2016). Previously, van der Weyden et al. (1989) recorded a dramatic drop in the body temperature of puppies immediately after birth, reaching a low within 40 min postpartum. ...
Article
Allomaternal care (AMC) is provided to the offspring by individuals other than the genetic mother, including several seemingly altruistic behaviors such as babysitting, carrying, nursing, crèching, or huddling for thermoregulation. To determine whether there is any allomaternal care among free-ranging domestic dogs, from March 2015 to May 2019 a total of eight dog groups consisting of 19 adult females (range 2–3 females per group) that were matrilineal relatives, i.e., maternal grandmothers, aunts, daughters, sisters were observed during pup-rearing period (1st to 13 weeks of pups’ life). During the first two weeks, lactating bitches were observed to spend the most time with their own pups and suckled for almost the entire observation period (30 min). Lactating mothers started to venture out of their dens for short foraging trips when the pups were 1 week old, but it was more frequent at 3 weeks of age. From the 3rd week of kin-related pups’ life the lactating mothers were observed to wean, with a parallel shift of nursing and regurgitation for the pups done by other kin-related females showing the evidence of allonursing. The occurrence of all types of nursing activities i.e., duration of contact, nursing, feeding by regurgitation, and protection of pups was higher among the mothers than among the allomothers. In the case of biological mothers, the frequency and duration of contact, nursing and feeding by regurgitation decreased as the puppies aged, meanwhile in the case of allomothers, the frequency and duration of contact, nursing and feeding by regurgitation increased until 6 weeks of age, before switching to a decreasing trend. Allonursing in free-ranging domestic dogs was more common among older bitches i.e., maternal grandmothers. We propose four possible reasons of allonursing in the case of free-ranging dogs- 1) having excess milk perhaps due to high pup mortality allonursing may evolve as low cost behavior in free-ranging dogs, 2) allonursing may provide substantial benefits to pups regarding growth, survival, and the transfer of immune compounds, 3) insufficiency of own mother’s milk may be one of the causes of allonursing, and 4) free-ranging domestic dogs nurse each other’s pups perhaps to promote a set of affiliating and permissive relationships among the group members. As the studied groups contained matrilineal related female dogs that helped each other with allonursing, this study strongly suggests the kin selection theory especially as allonursing is highly prevalent in other, closely related, gregarious wild canids (gray wolves, golden jackals).
... Dogs have a critical period for socialization to humans. Experiences during the socialization period of dogs have been shown to greatly influence fearfulness and aggressiveness to humans [65][66][67] . Early training of puppy dogs and early handling of lambs have been reported to induce positive reactions toward humans 68,69 . ...
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Gentle tactile stimuli have been shown to play an important role in the establishment and maintenance of affiliative social interactions. Oxytocin has also been shown to have similar actions. We investigated the effects of gentle stroking on affiliative relationships between humans and rats and the effects of gentle stroking on activation of oxytocin neurons. Male rats received 5-min stroking stimuli from an experimenter every other day for 4 weeks between 3 and 6 weeks of age (S3–6 group), for 4 weeks between 7 and 10 weeks of age (S7–10 group), or for 8 weeks between 3 and 10 weeks of age (S3–10 group). Control rats did not receive stroking stimuli. Rats in the S7–10 and S3–10 groups emitted 50-kHz calls, an index of positive emotion, more frequently during stroking stimuli. Rats in the S3–6, S7–10, and S3–10 groups showed affiliative behaviors toward the experimenter. Oxytocin neurons in the hypothalamic paraventricular nucleus of rats in the S3–6, S7–10, and S3–10 groups were activated following stroking stimuli. These findings revealed that post-weaning repeated stroking stimuli induce an affiliative relationship between rats and humans and activation of oxytocin neurons.
... Over the years, some conditions have been studied and deemed to be essential including the socialization of puppies during early life [5][6][7][8][9], genetics [10] and responsible ownership [11]. Optimal environmental surroundings adapted to the individual dog's level of development [12], the duration of maternal-puppy interaction [2] and puppies age at weaning time [13,14] also may influence the dog's temperament. Due to the significance of the source of the puppies, it is important to better know the breeding environment as well as the breeders' view on the importance of reproduction and maternal behavior to optimize the production of well-balanced dogs. ...
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In France, as in many other western countries, dogs are an important part of the society as pets or working animals. The exact demand for puppies in France is unknown, as is the proportion of dogs coming from different breeding sources. Nevertheless, the origin of puppies is important since young dogs from puppy mills and pet stores appear to be more likely to develop behavioral disorders. Puppies coming from responsible breeders, on the other hand, tend to be better adapted. In well-managed kennels, an explanation for these behavioral differences may be associated with greater contact of litters with the dam and humans. Another factor that might influence a dog’s temperament and character is maternal behavior. Although recent studies have shown that the quality of maternal care in dogs is important, direct effects on the development of behavioral problems such as fearfulness or noise sensitivity are still controversial. To better understand the view of breeders, due to an increased interest in maternal care of dogs, an online questionnaire was developed to assess the dog breeders’ profiles and to explore their perception of normal maternal and stress-related behaviors during the peripartum period. In addition, the management of the female during this critical time was queried. Three-hundred and forty-five French dog breeders, representing 91 breeds, completed the online survey. Considering the demographics of the responders, breeding activity in France is mostly family-based with 76% raising two breeds of dogs that produce, on average, five litters/year. Around 60% of the breeders use progesterone levels to determine breeding date. The whelping date is estimated using multiple criteria and most labors and deliveries happen under human supervision. The majority of behaviors associated to good maternal care are defined by the vast majority as being related to more attention of the bitch towards the puppies with the frequency of nursing and licking being important clues. Globally, the peripartum is perceived as a stressful period and to minimize stress and reassure the bitch the favored method used is increasing human presence. Problems related to maternal behavior were described, notably with primiparous bitches.
... This licking activity also serves to clean the puppy, the whelping box and the bitch's own anogenital area (Bleicher 1962). Oro-nasal interaction is also very important in stimulating the excretion process of the puppies (Rheingold 1963, Wilsson 2016. During the first 21 days of life, the puppies rely on the stimulus of licking by the mother (Fig 1) to defaecate and urinate (Grant 1987, Linde-Forsberg 2005. ...
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Here we review information on maternal behaviour in dogs, defined as a combination of all the acts of the mother towards her offspring, which begins before parturition and continues until weaning. In dogs, maternal care is measured using the most commonly observed behaviours, such as the time spent in contact, licking/grooming and nursing of the puppies. Since newborn puppies have a very limited capacity for movement, maternal interaction is essential to their survival, nourishment and protection. It is also an important element of the bonding process between puppies and the bitch and is thought to play a role in the social development of the puppies. Nevertheless, some questions still need to be clarified, such as the best way to quantify factors that may interfere with maternal behaviour. In recent studies, maternal care, or maternal style, was measured using a scoring system and found to be influenced by factors such as litter size, breed and parity, or even human interaction. However, the impact of the emotional state of the bitch and the quality of maternal behaviour on puppy survival and development remain unclear. The long-lasting effects of mother-puppy interactions on puppy behaviour during their adult life are still poorly understood, despite their importance for breeders who wish to prevent future problem behaviours.
... However, a drop in the UK GSD population has been observed in the last years and aggressive behaviour has been identified as one of the possible causes for the breed's diminishing popularity (O'Neill et al., 2017). Furthermore, the observation was made that about 30% of GSDs bred for the Swedish armed forces that were raised in foster families had to be rehomed to another foster home at least once during their first 18 months of life (Wilsson, 2016). High scores for 'Confidence' and 'Engagement' temperament traits were identified as major risk factors for re-homing. ...
Article
As companion animals, a dog's lifestyle is mainly determined by its owner. Discrepancies between the dog's preferences and the owner's lifestyle might lead to the occurrence of unwanted behaviours that affect both the owner-dog relationship and the dog's welfare. The aim of this study was to identify behavioural traits that are characteristic of German Shepherd dogs (GSDs), and to analyse the relation between behavioural traits and demographic and management factors. Dog owners from the UK and Sweden were asked to complete two surveys, the established C-BARQ behavioural survey and a lifestyle survey developed for the study. A principal component analysis was applied to determine behavioural components for GSDs. Fifteen components were found to sufficiently explain the variance in the responses to C-BARQ, with the components Stranger-directed aggression and Dog-directed aggression explaining the greatest proportion of the variance in the data (12% and 10%, respectively). Linear models were then applied to assess the relationship between behaviour components and lifestyle factors using backward elimination to identify the model that best predicted the behaviour component. The cohort (UK or Sweden) and the age of the dog were associated with the highest number of behaviour components. This study showed that various demographic and management factors were associated with the expression of behavioural traits in GSDs. Results from this analyses may help to understand the interaction between the expression of external factors and dog behavioural traits and thus, improve the well-being of dogs and owners by reducing problem behaviours.
... An animal's adult behavioral phenotype is determined by the interaction between the individual's genotype, experience, and developmental environment (Scott & Fuller, 1965, p. 293;Jacobs et al., 2004;Wilsson, 2016). Evidence supports a genetic component for psychobehavioral traits in dogs such as anxiety/fear, noise phobia, human aversion, obsessive-compulsive disorder, predatory behavior, and 2 types of aggression: impulse/control and conspecific (Murphree & Dykman, 1965;Overall & Dunham, 2002;Liinamo et al., 2007;Dodman et al., 2010;Pierantoni et al., 2011;Overall et al., 2016)dmany of the behaviors demonstrated as having a higher prevalence in CBE-produced dogs. ...
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A review of seven published studies and one anecdotal report involving dogs born in high-volume commercial breeding establishments (CBE) and sold to the consumer directly via the Internet or indirectly through retail pet stores revealed an increased incidence of behavioral and emotional problems that cause distress in adulthood compared with dogs from other sources, especially breeders. The most consistent finding among studies is an increase in aggression, which is most commonly directed toward the dog’s owners and family members but also to unfamiliar people, and other dogs. Increased fear was also identified in response to unfamiliar people, children, other dogs, nonsocial stimuli, and when taken on walks. Undesirable behaviors related to separation and/or attention-seeking and a heightened sensitivity to touch have been reported.
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For dog breeders, parturition is a critical stage in the reproductive cycle of the dam. Evidence in other mammals suggests that a difficult labour can influence maternal behaviour and offspring viability during the first hours postpartum. However, the effect of whelping difficulty on the onset of maternal behaviour has not yet been investigated in domestic dogs. Here we developed an ease of whelping (EoW) index in dams maintained within a Commercial dog Breeding Establishment (CBE) environment and investigated the relationship between intrinsic and extrinsic factors (breed group according to size/weight, litter size, parity, whelping season and origin of the dam), EoW, early maternal behaviour and puppy perinatal mortality. The behaviour of 30 dams was observed throughout the whelping process, starting 24 h before delivery of the first puppy until birth of the last puppy. Parturition duration, birth interval, and behaviours indicative of distress, restlessness, and general activity were scored and included in a Principal Component Analysis to construct the EoW index. Subsequently, mother–pup interactions and puppy perinatal mortality were recorded during the first 24 and 72 h postpartum respectively. Results showed that EoW was significantly affected by whelping season, litter size and origin of the dam (whether she was born and raised within the CBE or brought in). Furthermore, mothers that experienced more difficult parturitions (higher EoW score) spent more time lying in contact with their puppies during the first 24 h postpartum. Time in contact with puppies was also significantly affected by breed group. Nursing duration was significantly affected by breed group and origin of the dam. Additionally, medium-size breed (10–20 kg) puppies were significantly less likely to experience perinatal mortality than large breeds (> 20 kg). These findings are particularly relevant for the welfare of breeding dams maintained in large-scale CBEs where the staff-to-dog ratio might be insufficient to adequately manage multiple simultaneous parturitions.
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Fear-related problems are common among Rough Collies (RC) in Sweden. Annually, on average > 200 RC are subjected to the Dog Mentality Assessment (DMA), a temperament test during which 33 behavioral reactions are rated. Previous research has shown that a dog's DMA result can be condensed into 5 underlying personality traits. The aim of the study was to evaluate if DMA is possible to use for selection for temperament in Swedish RC, in particular to decrease everyday life fearfulness. We also wanted to compare 2 methods to compute the personality traits: summated scales (SS) and factor scores (FS). DMA data for 2,953 RC were used to estimate genetic parameters for the 5 personality traits (both SS and FS), using a linear animal model including fixed effects of sex, year and month of test, and random effects of litter, judge, test occasion, genetic effect of the individual and residual. Age at test was included as linear and quadratic regressions. DMA personality trait heritability estimates ranged from 0.13 to 0.25. The SS showed greater or equal heritability estimates compared with the FS. To validate the DMA, data on everyday life behavior of 1,738 RC were collected using an extended version of the Canine Behavioral Assessment and Research Questionnaire. Each dog's questionnaire result was condensed into 18 underlying behavioral subscales. Genetic parameters for the subscales were estimated using a linear animal model, including a fixed effect of sex, and random genetic effect of the individual and residual. Age when the questionnaire was completed was included as linear and quadratic regressions. Heritability estimates for the questionnaire subscales were 0.06 to 0.36. There were high and significant genetic correlations between DMA personality traits and questionnaire subscales. For instance, the DMA personality trait Curiosity/Fearlessness correlated strongly genetically to the questionnaire subscale Non-social fear (-0.70), DMA Sociability to Stranger-directed interest (0.87) and Stranger-directed fear (-0.80), DMA Playfulness to Human-directed play interest (0.63), and DMA Chase-proneness to Chasing (0.73). We could not detect any obvious difference in validity between DMA SS and FS. We conclude that DMA is an effective tool for selection of breeding animals with the goal to decrease everyday life fearfulness among Swedish RC. DMA can also be used for breeding for other traits. The SS method seems to perform at least as good the FS method.
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With the dual purpose of selecting both breeding animals and dogs for training, all German Shepherd Dogs in the Swedish Armed Forces (SAF) breeding program are subjected to a temperament test. During the test, the dog’s behavioral responses are rated with two different methods. In a previous study, using Principal Components Analysis (PCA) on the test items, five and three underlying behavioral dimensions from each rating method were defined. Three of the dimensions were reported to correlate significantly to training success. Using test results from 873 dogs, we estimated heritabilities of, and genetic correlations among, the 38 test items and the eight underlying behavioral dimensions. Parameters were estimated using a mixed linear animal model including fixed effects of sex, training level, test age and test year-location combination, and random effects of litter, genetic effect of the individual and residual. Heritabilities ranged from 0.00 to 0.28 (SE=0.05-0.10), which is similar to what has been reported in previous studies of traits defined and measured in a comparable way. Genetic correlations were high (rg=0.92-0.98, SE=0.08-0.12) between dimensions derived from each rating method and defined as either confidence, engagement or aggressiveness, but relatively weak among these dimensions within rating method (rg=0.00-0.45, SE=0.29-0.41). Our results imply that the test measures three separate behavioral dimensions and that the SAF temperament test as a whole is possible to utilize for selection of dogs for breeding, but also that some test items should be measured differently to be meaningful for genetic selection purposes. Furthermore, aggregating variables based on a PCA performed on phenotypic data might be sub-optimal when defining dimensions for breeding purposes; taking genetic parameters into consideration resulted in generally higher heritabilities for the dimensions.
Article
Early life experiences are known to shape the behavioural development of animals, and therefore events occurring during preadolescence and adolescence may have long-term effects. In dogs, this period of time may be important for later behaviour and thereby also the suitability of dogs for different working tasks. We used the breeding practice for Swedish military working dogs to investigate this possibility. German Shepherds were bred at a central facility and then kept in host families for about a year, before participating in a standardised test determining their temperament, behaviour, and suitability for further training. We surveyed the link between the behaviour of 71 prospective military working dogs dogs in their home situations during the first year of life as assessed by an amended C-BARQ survey, and their performance in a temperament test (T-test) applied at about 17 months of age. Dogs which scored high for C-BARQ category “Trainability” showed a significantly higher success rate in the T-test (P < 0.001), while dogs that scored high for “Stranger-Directed Fear”, “Non-social Fear” and “Dog-Directed Fear” showed a significantly lower success rate (all P < 0.05). Also dogs with higher C-BARQ scores on “Hyperactivity/Restlessness, Difficulties in Settling Down” (P = 0.028), and “Chasing/Following Shadows or Light Spots” (P = 0.035) were more successful, as were dogs left longer times at home (2.97 ± 0.32 vs. 2.04 ± 0.33 h/day; P = 0.050). Index value, describing the expected success rate in the T-test, was negatively correlated with “Non-social fear” (r = -0.35) and “Stranger directed fear” (r = -0.35). The combined effect of the significant C-BARQ categories explained 29.5% of the variance in the later T-test results P = 0.006). The results indicate that the experiences and behaviour of the dogs during their first year of life is crucial in determining their later behaviour and temperament, something that could potentially be used to improve selection procedures for working dogs. Furthermore, an unsuspected result was that success in the T-test was correlated with behaviours usually associated with problem behaviour, which calls for a deeper analysis of the selection criteria used for working dogs.
An animal can only achieve its full genetic potential if it has lived its life in an ideal environment. Few environments are ideal; they may be unfavourable for numerous reasons and for different lengths of time. Indeed, variations on these themes are almost infinitely possible, but concrete examples will be selected and their effects on the lives of animals and of man demonstrated. Time comes into all this, but its importance and the difference between chronological and biological time have not been properly appreciated. The interactions of time and the environment on the growth of animals and of their organs are complex, but recent work on malnutrition and growth has given us some insight into the matter. Theories that have been formulated are discussed, but none of those yet put forward explain all the facts that can be demonstrated experimentally, and studies that might provide clues have been neglected.
Article
The problem at the South African Police Service Dog Breeding Centre was that most of their progenies were unsuitable as police dogs. Behaviour tests were developed specifically for police dogs to predict their efficiency as adults. Puppies from the age of 8 weeks were exposed to situations that they probably would encounter in their work as police dogs. These experiences included crossing of obstacles, retrieval of objects, startle stimuli and aggression. In the longitudinal study of 2 years it was found that all the tests had statistical significance to a greater or lesser extent, except the gunshot test. The most significant tests were retrieval at 8 weeks and aggression at 9 months. These tests thus enable selection for suitable dogs as early as 8 weeks of age, but not later than 9 months. The conclusion is that reliable tests can predict adult police dog efficiency and in doing so, save unnecessary training and other costs on unsuccessful dogs.
Article
Early neurological stimulation (ENS) has been proposed to enhance the natural abilities of dogs. This kind of stimulation involves subjecting pups aged between 3 and 16 days to mild forms of stimulation leading to “stress,” and is said to lead to faster maturation and better problem-solving abilities later in life. ENS resulted from a U.S. Military program called Bio Sensor, and is currently being used in some other working dog programs. It has been part of the breeding program for mine detection dogs at the Global Training Centre (GTC, part of Norwegian People’s Aid) for 4 years.To investigate the effects of ENS on the basis of a previous study (Battaglia, 2009, J. Vet. Behav.: Clin. Appl. Res. 4, 203-210), 10 litters born since the spring of 2008 at the GTC were randomly divided into the following 2 groups: (1) those receiving ENS, and (2) those receiving the same amount of human attention without being subjected to the ENS exercises. Developmental parameters were monitored by the kennel staff. The pups were subjected to testing at approximately 10 weeks of age by investigators who were blinded to treatment. Their careers as working dogs were monitored.There was no observed effect of ENS on either the development of the pups when compared with those who were exposed to the standard GTC stimulation program within the same age range or on the later training results of the dogs in their careers as mine detection dogs. This lack of effect could well be the result of the very rich standards of the GTC socialization program that is given to these dogs.
Article
In recent years much interest has been focused on early experiences and numerous studies have been carried out in order to understand their effects on the behaviour of adult animals. The aim of this preliminary study was to assess the effects of early gentling and early environment on the emotional stability of puppies. Forty-three dogs (16 females and 27 males) from seven litters were used. Four of these litters (in total 23 puppies) were raised in a professional breeding kennel, while the remaining litters lived in their owner's home, in a family atmosphere. Half of every litter was gently handled daily from the 3rd day postpartum until the 21st. In order to assess the puppies’ emotionality, an isolation test followed by an arena test were conducted on every puppy at the age of 8 weeks. Video recording of the tests allowed the measurement of each puppy's vocalization and exploratory activity. Data were analysed with the Newmann–Keuls’ test comparing four groups: non-handled puppies raised in family (NHF); handled puppies raised in family (HF); non-handled puppies raised in a professional breeding kennel (NHB); handled puppies raised in a professional breeding kennel (HB).The results suggest that early environment strongly influences the emotional stability of puppies when put in isolation: latency to the first yelp was longer (p
Article
During a 6-year period 867 8-week old German shepherd puppies were subjected to a behaviour test containing 10 different score groups. The weight at each tenth day up to 50 days of age was registered as well as litter size and parity of mother. All dogs were also tested at the age of 450–600 days. Puppies born during the first year and during the first 5 months of the second year (period 1) weighed 25% more at 50 days of age compared to those born during the last 7 months of year 2 and in year 3–6 (period 2). Puppy weight decreased with increasing litter size. Parity of mother had some effect on puppy behaviour however none on adult behaviour. Puppy weight affected the behaviour of puppies and adult dogs, however mainly in females. Larger female puppies were more active and explorative in the puppy test and scored higher for defence drive and hardness as well as in the concluding index value at adult age. Significant differences between period 1 and 2 were found both in the puppy test and in the test results of adult dogs. It is suggested that theses effects were caused by the change in material used in the whelping boxes. The corrugated cardboard used in period 1 was assumed to have an effect on the neonatal puppies similar to what previously have been described as early handling. The change in material used in the whelping boxes was also shown to affect growth in puppies. The effects were different in winter than in summer. It is also suggested that the behaviour of puppies is greatly affected by degree of maturation and that there may be differences in maturation due to gender and litter. It is also possible that maturation is affected by weight which then would explain the correspondence between weight and behaviour.
Article
Seventeen litters of German Shepherd dogs were observed for 5–7 days per week between 3 and 8 weeks post-partum. Social behaviour patterns, aggressive signals towards the puppies and nursing were quantified. Mothers were found to differ in the frequency of both social and aggressive behaviour. Nursing declined during the period, while both agonistic and grooming behaviour towards puppies increased until the 7th week. During Week 7, agonistic behaviour patterns were found to be significantly correlated to grooming behaviour patterns. Some of these behaviour traits were significantly correlated to the puppies performance on a puppy test given at the age of 8 weeks. It is suggested that the interaction between mother and offspring may facilitate the appearance of submission, and the effects on later trainability are discussed.
Article
The behaviour test results of 1310 German shepherds and 797 Labrador retrievers, 450–600 days of age, were evaluated. The purpose was to investigate whether the behaviour tests, previously used at the Swedish Dog Training Centre, could be used to select dogs for different kinds of work and for breeding. Ten behavioural characteristics were scored based on the dogs' reactions in seven different test situations. All tests were conducted by one experienced person.Marked differences in mental characteristics were found between breeds and sexes, but particularly between various categories of service dogs. Regardless of differences in the behaviour profiles of these service categories, there were marked similarities between different categories of service dogs compared with dogs found to be unsuitable for training as service dogs. To interpret the data, an index value was created, based on the test results for each individual dog, and was found to be an excellent instrument for selecting dogs for different types of work.For both breeds the factor analysis resulted in four factors. In comparing the different characteristics, the same pattern was found in both breeds, with the exception of the characteristic prey drive, which seems to be irrelevant for Labrador retrievers. The conclusion is that a subjective evaluation of complex behaviour parameters can be used as a tool for selecting dogs suitable as service dogs. The results also show that the use and correct interpretation of behaviour tests can be enhanced by adjusting the results for each breed and planned service category.
Article
Heritability calculated for characteristics evaluated in behavioural tests can be used as a tool to select different kinds of service dogs. The evaluation was based on the test results of 1310 German shepherds and 797 Labrador retrievers. The heritability for all evaluated characteristics of the two breeds was significantly different from zero with the exception of the characteristics prey drive in Labrador retrievers.The test results for each characteristic were summarised to form an index value which simplified the interpretation of the test results. The heritability for this index value was 0.24 for both German shepherds and Labrador retrievers, a value that must be considered high as it included all tested parameters. The heritability was also calculated for the four factors derived from a factor analysis of the test results. Heritability estimates for these four factors were 0.15 to 0.32The results show that complex behavioural patterns in dogs can be subjectively evaluated by an experienced person and that no more than a few characteristics are needed in order to describe the differences between dogs.Breeding results in a German shepherd population at the Swedish Dog Training Centre (SDTC) improved a relatively short time after the initiation of basing the selection of breeding animals on the index value of each individual animal. German shepherds bred by the SDTC also had higher index values than privately bred dogs which shows the importance of a goal-oriented breeding programme with emphasis on service dog characteristics.Finally different ways in which to collect information about dog behaviour are discussed. It is suggested that a subjective evaluation of certain behaviour characteristics is preferred to a factual description of reactions.
Article
It is not capacity that explains the differences that exist between individuals, because most seem to have far more capacity than they will ever use. The differences that exist between individuals seem to be related to something else. Researchers have studied these phenomena and have looked for new ways to stimulate individuals to improve their natural abilities. Some of the methods discovered have produced lifelong effects. Today, many of the differences between individuals can now be explained by the use of early stimulation methods, socialization, and enrichment experiences. For example, early life has been found to be a time when the physical immaturity of an organism is susceptible and responsive to a restricted but important class of stimuli. Because of its importance, many studies have focused on the first year of life. Newborn pups are different from adult dogs in several respects. When born, pups' eyes are closed, their temperature is subnormal, and their digestive system has a limited capacity, requiring periodic stimulation by their dam, who routinely licks them to promote digestion. Other mammals such as mice and rats are also born with limitations, and they also have been found to show a similar sensitivity to the effects of early stimulation. Studies show that removing them from their nest for 3 min each day during the first 5–10 days of life causes body temperatures to fall below normal. This mild form of stress is sufficient to stimulate hormonal, adrenal, and pituitary systems. When tested later as adults, these same animals were better able to withstand stress than littermates who were not exposed to the same early stress exercises. As adults, they responded to stress in “a graded” fashion, whereas their nonstressed littermates responded in an “all or nothing way.” The results show that early stimulation can have positive results but must be used with caution. Too much stress can cause pathologic adversities rather than physical or psychologic superiority. Socialization and enrichment experiences have also been found to make important differences in the development of the adult dog.
Article
As a consequence of their living close to humans as pets, for working purposes or as laboratory animals, dogs give evidence of behavioural variability, stemming from their innate capacities as well as from environmental influences. This paper reviews the behavioural tests used for dogs—tests which serve as an evaluation tool and those which serve as a means of classifying individual animals. In search of a consensus and standardisation, some material and methodological aspects of behavioural testing in dogs were collected. Behavioural test parameters that were taken into account were the terminology of the temperament concept, the test quality requirements and their implementation in the literature, the characteristics of the dog tested (source, breed, age, sex), the characteristics of the social and environmental stimuli used to elicit canine behaviour, the characteristics of the behavioural variables collected and the characteristics of the physical and physiological concomitant data obtained while assessing the behaviour. This review brings to light a lack of consensus regarding all these parameters. The procedures of testing are often particular to the investigator and thus unique. We emphasised this statement by comparing six research studies using a ball, carried out over 40 years. In view of all these differences in methodology, standardisation is suggested through the creation of a reference manual.
Article
In order to test if adult behaviour could be predicted at eight weeks of age, 630 German shepherd puppies were tested. All dogs were also tested at 450–600 days of age according to regimen used to select service dogs. Significant gender differences were found in 4 of the 10 score groups of the puppy test. There were also significant correlations between the puppy test score groups. Correspondence of puppy test results to performance at adult age was negligible and the puppy test was therefore not found useful in predicting adult suitability for service dog work. Heritability was medium high or high for behaviour characteristics of the score groups in the puppy test. Maternal effects on the puppy test results were found when comparing estimations based on sire and dam variances. It also suggests that maternal effects are more likely to be seen in juvenile than in adult behaviour.
Article
Submission in the wolf and dog is defined on the basis ot its motivation: submission is the effort of the inferior to attain friendly or harmonic social integration. Submission functions as an appeal or a contribution to social integration, but only if it meets a corresponding attitude in the superior. The form of submissive behavior in wolf and dog is ritualized and symbolized cub-behavior. Two main forms of submissive behavior occur in wolf and dog: active submission, derived from begging for milk or food, and passive submission, derived from the posture which the cub adopts when cleaned by its mother. The definition of submission is generally applicable to vertebrates living in groups based on intimacy and a social hierarchical order. The concept of submission as the role of the defeated in the terminal phase of fight with the function to inhibit automatically aggression in the superior should be dismissed. In vertebrates at least three types of conflict with different terminal phases occur: (1). Severe fight based on intolerance; ends with flight by the inferior or with his death. (2). Ritualized fight over a privilege; ends with the “giving-up-the-claim ritual” of the inferior, which automatically blocks the aggression of the superior. (3). Minor conflict in closed groups; settled by submissive behavior of the inferior. In closed vertebrate groups, intermediate forms between (1) and (3) occur, depending on the proportion between activated intimacy and intolerance.
Article
To assess effects of foods fortified with docosahexaenoic acid (DHA)-rich fish oil on cognitive, memory, psychomotor, immunologic, and retinal function and other measures of development in healthy puppies. Evaluation study. 48 Beagle puppies. Puppies were assigned to 3 groups after weaning (n = 16/group) and received 1 of 3 foods (low-DHA, moderate-DHA, or high-DHA food) as their sole source of nutrition until 1 year of age. Visual discrimination learning and memory tasks, psychomotor performance tasks, and physiologic tests including blood and serum analysis, electroretinography, and dual-energy x-ray absorptiometry were performed at various time points. Anti-rabies virus antibody titers were evaluated 1, 2, 4, and 8 weeks after vaccination at 16 weeks of age. Foods had similar proximate analysis results but varied in concentration of DHA from fish oil; the high-DHA food also contained higher concentrations of vitamin E, taurine, choline, and l-carnitine than did other foods. The high-DHA group had significantly better results for reversal task learning, visual contrast discrimination, and early psychomotor performance in side-to-side navigation through an obstacle-containing maze than did the moderate-DHA and low-DHA groups. The high-DHA group had significantly higher anti-rabies antibody titers 1 and 2 weeks after vaccination than did other groups. Peak b-wave amplitudes during scotopic electroretinography were positively correlated with serum DHA concentrations at all evaluated time points. Dietary fortification with fish oils rich in DHA and possibly other nutrients implicated in neurocognitive development following weaning improved cognitive, memory, psychomotor, immunologic, and retinal functions in growing dogs.
Article
Behavioral activity of 7-week-old German shepherd puppies was tested and the activities analyzed if they could be used for predicting police efficiency of the individual. In total 206 individuals sired by 42 sires and 44 dams were used. The activities were divided into 10 tasks in which reactions and behavior of pups were scored from 0 to 5 points. All pups were tested separately from other conspecifics. Probability that the puppy will pass the certification was tested by a logistic regression. Of the 206 puppies, 148 passed the certification while 58 failed. Some tested behavioral variables were moderately to highly correlated with one another. Therefore we applied a factor analysis. Three factors were retained accounting for 100% of the shared variance. After inspection of the rotated factor pattern matrix and its confidence intervals, it appeared that variables "Independent movement and interactions with the tester", "Negotiating obstacles", "Entering a room", "Behavior toward a person", and "Behavior in new environments" loaded on Factor 1 ("Factor for movement"), while variables "Response to distracting stimuli caused by a shovel", "Response to a distracting noise while left alone in a room", and "Response to loud distracting stimuli" on Factor 2 ("Factor for responding to noise") and variables "Retrieval" and "Tug of war" on Factor 3 ("Factor for attitude to predation"). In the final logistic regression model, the probability that the puppy will pass the certification depended on the higher weight at the time of testing (chi(2)((1)) = 12.00, P = 0.0005), on the "Factor for attitude to predation" (chi(2)((1)) = 11.63, P = 0.0007), on the "Factor for responding to noise", where the higher the score, the weaker was the response (chi(2)((1)) = 5.16, P = 0.0232), and on the "Factor for movement" showing an increasing probability with decreasing score (chi(2)((1)) = 5.25, P = 0.0219). The tests in (1) = our study seem to be a good base which might enable selection for suitable dogs as early as 7 weeks of age. The puppies having high probability to pass certification in adulthood were heavy individuals willing to chase, catch, and fetch a tennis ball, and follow a rag drawn away from them, while weakly responding to a distracting noise in various situations and showing low activity while negotiating obstacles and moving and interacting with the tester. To conclude, contrary to skeptical assumptions expressed by various authors, the specific puppy tests for police dogs provide a reliable tool for predicting future service ability of a puppy. Differences in methodology are likely to contribute to a lack of consensus among various studies. (c) 2007 Elsevier B.V. All rights reserved.
Article
Spurred by theoretical and applied goals, the study of dog temperament has begun to garner considerable research attention. The researchers studying temperament in dogs come from varied backgrounds, bringing with them diverse perspectives, and publishing in a broad range of journals. This paper reviews and evaluates the disparate work on canine temperament. We begin by summarizing general trends in research on canine temperament. To identify specific patterns, we propose several frameworks for organizing the literature based on the methods of assessment, the breeds examined, the purpose of the studies, the age at which the dogs were tested, the breeding and rearing environment, and the sexual status of the dogs. Next, an expert-sorting study shows that the enormous number of temperament traits examined can be usefully classified into seven broad dimensions. Meta-analyses of the findings pertaining to inter-rater agreement, test–retest reliability, internal consistency, and convergent validity generally support the reliability and validity of canine temperament tests but more studies are needed to support these preliminary findings. Studies examining discriminant validity are needed, as preliminary findings on discriminant validity are mixed. We close by drawing 18 conclusions about the field, identifying the major theoretical and empirical questions that remain to be addressed. # 2005 Elsevier B.V. All rights reserved.
Article
The aim of this study was to study genetic (co)variation of broader behavioural traits in German shepherd dogs and to test whether there is maternal and litter influence on these traits. Data were extracted from the Swedish Dog Mentality Assessment (DMA) from 1989 to 2001 on 5959 German shepherd dogs. Based on previous results, personality traits were created from the 15 behavioural variables extracted from the test. These personality traits were (1) Playfulness, (2) Chase-proneness, (3) Curiosity/Fearlessness, and (4) Aggressiveness. A trait Boldness was constructed from all behaviour variables except those included in Aggressiveness. Mixed linear models with fixed effects of sex, test type, test year, test month, age, and judge were used. Models with all combinations of random effects of animal (direct genetic), genetic and non-genetic maternal, and litter were tested. The best model included effects of animal and litter. Direct heritability estimates were between 0.09 and 0.23, highest for Playfulness and Curiosity/Fearlessness. Maternal heritabilities were all low (0.01–0.08), lowest and not significant if litter or non-genetic maternal effects were included in the model. Additive genetic correlations among Playfulness, Chase-proneness, and Curiosity/Fearlessness were higher (0.54–0.74) than genetic correlations with Aggressiveness (0.29–0.40). Litter variance ratios (c2) were larger than the maternal heritabilities (0.03–0.10). Boldness had a direct heritability estimate of 0.27 and a direct genetic correlation with Aggressiveness of 0.37. We conclude that there is substantial additive genetic variation, that the mother has rather little influence (both genetically and environmentally) and that the litter seems to have a larger influence than the mother for these personality traits. Genetic improvement in these behaviour traits is thus possible.
Article
The present study examined the prevalence of behaviours in dogs separated from the litter for adoption at different ages. Seventy adult dogs separated from their dam and littermates and adopted between the ages of 30 and 40 days were compared with 70 adult dogs that had been taken from the litter for adoption at two months. Owners were asked to complete a questionnaire eliciting information on whether their dog exhibited potentially problematic behaviours when in its usual environment. Binary logistic regression analysis was performed to investigate whether the age at which the dog was separated from the litter might predispose it to developing undesirable behaviours. The odds of displaying destructiveness, excessive barking, fearfulness on walks, reactivity to noises, toy possessiveness, food possessiveness and attention-seeking were significantly greater for the dogs that had been removed from the litter earlier during the socialisation period. In addition, dogs purchased from a pet shop at 30 to 40 days of age were reported to exhibit some of the listed behaviours with a significantly higher frequency than dogs purchased from a pet shop at two months. No significant differences were observed with dogs obtained from other types of sources. The dogs in the youngest age group (18 to 36 months) had a higher probability of displaying destructiveness and tail chasing. These findings indicate that, compared with dogs that remained with their social group for 60 days, dogs that had been separated from the litter earlier were more likely to exhibit potentially problematic behaviours, especially if they came from a pet shop.
Article
Thesis (doctoral)--Stockholm University, 1997.
Article
Several years ago Levine, Denenberg, Weininger, Ader, and others described the effects of postnatal "handling" on the development of behavioral and endocrine responses to stress. The handling procedure usually involved removing rat pups from their cages, placing the animals together in small containers, and 15-20 min later, returning the animals to their cages and their mothers. The manipulation was performed daily for the first 21 days of life. As adults, handled (H) rats exhibited attenuated fearfulness (e.g., decreased freezing, increased exploration) in novel environments and a less pronounced increase in the secretion of adrenal glucocorticoids in response to a variety of stressors. These findings clearly demonstrated that the development of rudimentary, adaptive responses to stress could be modified by environmental events. We have followed on these earlier handling studies, convinced that this paradigm provides a marvelous opportunity to examine how subtle variations in the early environment alter the development of specific biochemical systems in the brain, leading to stable individual differences in biological responses to stimuli that threaten homeostasis. In this work we have shown how early handling influences the neurochemical development of certain brain regions that regulate the adrenocortical response to stress. Neonatal handling increases the efficiency of this endocrine response to stress, preventing excessive exposure to the highly catabolic adrenal steroids. In later life, this effect appears to protect the animal from potentially damaging effects of these steroids, ensuring the anatomical integrity of brain structures involved in cognitive functioning.
An animal can only achieve its full genetic potential if it has lived its life in an ideal environment. Few environments are ideal; they may be unfavorable for numerous reasons and for different lengths of time. Indeed, variations on these themes are almost infinitely possible, but concrete examples will be selected and their effects on the lives of animals and of man demonstrated. Time comes into all this, but its importance and the difference between chronological and biological time have not been properly appreciated. The interactions of time and the environment on the growth of animals and of their organs are complex, but recent work on malnutrition and growth has given us some insight into the matter. Theories that have been formulated are discussed, but none of those yet put forward explain all the facts that can be demonstrated experimentally, and studies that might provide clues have been neglected.
Article
The effects of handling from birth to 5 weeks and isolation from 4 to 5 weeks were studied in twenty-tow dogs and contrasted with the behaviour of control subjects raised under normal rearing conditions. Differences in behaviour, heart rate and EEG activity were evident in the three differentially reared groups of dogs and were attributed to the effects of handling and isolation in the experimental groups as compared to the control group. Preliminary biochemical data (adrenal and CNS analysis) are included and some correlation in the differentially reared groups is shown. These data in part support similar findings in other species reviewed in this paper.
Article
NEONATAL MICE OF THE STRAIN A 2G/TB WERE EXPOSED BETWEEN DAYS 6 AND 11 TO EITHER EAR MARKING (PUNCHED HOLE) ALONE OR WITH 90 MIN/DAY THERMAL CHANGE (WARM EXPOSED GROUP AT 34DEGREES C AND COLD EXPOSED GROUP AT 21DEGREES C). ALL EXPERIMENTAL GROUPS SHOWED GREATER SURVIVAL ON EXPOSURE TO COLD AT 3 WK. OF AGE THAN CONTROLS. PARENTAL ATTENTION (LICKING, CARRYING) WAS GREATER WITH NESTLING SUSTAINING AN EAR PUNCH THAN CONTROLS. A GENERAL INFLUENCE OF MATERNAL ATTENTION ON NERVOUS SYSTEM DEVELOPMENT IS SUGGESTED. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
Some rat pups were handled for 20 days in infancy, while others were not. When the rats reached adulthood the females were bred. Some of the offspring were left with their natural mothers, others were fostered to mothers of the same background (handled/nonhandled) as that of their natural mothers, while still others were fostered to mothers with a different background from that of their natural mothers. The offspring were weaned and weighed at 21 days; at 50 days, activity and defecation scores were obtained in the open field. The weights at weaning and the defecation scores at 50 days were significantly influenced by the experience in infancy of the "postnatal" mother, whether she was the natural mother or a foster mother. The natural mother and the foster mother jointly affected the open-field activity of the offspring.
Article
The 1st experiment (N = 81) consisted of submitting independent groups of rat litters to electric shocks of 0.2 ma. during 3 min. to Ss 1-5, 1-3, 3-5, 2 or 4 days old; the control group was not administered shock. The 2nd experiment (N = 36) repeated the conditions of the control of shock on Day 2 and shock on Day 4. At adult age all the Ss were tested for avoidance learning. In the 1st experiment the general mean of experimental groups was higher than that of control groups (p < .01). When the experimental group which received shock at the age of 2 days was eliminated, the mean difference was significant (p < .05). In the 2 experiments, the Ss submitted to shock at the age of 4 days were significantly superior in avoidance learning than the Ss submitted to shock when 2 days old. Discussion of the results suggests the hypothesis of critical period and the hypothesis of intensity. The latter is considered as more consistent with the data. (French summary)
Th e Sw edish Arm ed Forces tem peram en t test gives in form ation on gen etic differen ces am on g dogs
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