Canine Myofascial Kinetic Lines: A Descriptive Dissection Study Including Related Function and Locomotion and Comparison of the Human and Equine Myofascial Kinetic Lines

Aim: This dissection study was conducted to verify if the Myofascial kinetic lines, outlined in detail in humans and recently documented in horses, were present in dogs. These dynamic lines present rows of interconnected muscles, myofascia and other fascia structures, which influence the biomechanics of the spine and limbs. Methods: Forty-two dogs of different breeds and genders were dissected, imaged, and videoed. Results: Similar kinetic lines were verified in the dog, as described in humans and horses, and additionally, three new branches of the lines were discovered. The kinetic lines described were three superficial lines: Dorsal, Ventral, and Lateral, which all started in the hindlimb and ended in the temporal and occipital regions. These lines act respectively in spinal extension, flexion, and lateral flexion. Three profound lines, which started in the tail and ended in the head. The Deep Dorsal Line followed the transversospinal myofascia. The Deep Ventral Line showed an additional start deep in the medial hind limb, continued in the hypaxial myofascia, and enveloped all the viscera. Also, the Deep Lateral Line started in the hindlimb but parted along the trunk in the deep lateral myofascial structures. Two helical lines crossed the midline two or three times and served to rotate the spine. The Functional Line established a sling from the axilla to the contralateral stifle and presented a new ipsilateral branch. The Spiral Line connected the head and the ipsilateral tarsus and additionally presented a new straight branch. The four front limb lines describe their motion: the Front Limb Protraction and Retraction, Adduction, and Abduction Lines. Conclusion: The canine lines mirrored the equine and human lines with exceptions due to differences in anatomy, foot posture, lumbosacral flexibility, and their biomechanical constitution as predator versus prey animals. Additionally, three new canine branches were verified and described.

Free-ranging dogs match a human’s preference in a foraging task

Social learning is a mechanism used by many species to effciently gain information about their environment.Although many animals live in an environment where members of other species are present,little is known about interspecifc social learning.Domesticated and urbanized species provide the opportunity to investigate whether nonhuman animals can learn from heterospecifcs such as humans,who are integral parts of their social landscape.Although domestic dogs Canis familiaris have been intensively researched for their ability to learn from humans,most studies have focused on dogs living as pets.However,free-ranging dogs represent the majority of the world’s dog population,they live alongside humans,scavenge on human refuse,and are subject to natural and sexual selection.Thus,free-ranging dogs with extensive exposure to humans and their artifacts provide the opportunity to investigate interspecifc social learning in a naturalistic setting,where learning from humans might be a beneft for them.Here we tested individual free-ranging dogs in a between-subject design:Dogs in the control group could spontaneously choose between two novel and differently patterned food-delivering boxes.In the experimental group,instead,dogs could frst observe an unfamiliar human approaching and eating from 1 of the 2 boxes.We provide the frst evidence that free-ranging dogs match the choice of an unfamiliar human.These results show that at least simple forms of interspecifc social learning might be involved in dogs’success in living alongside humans in a complex urbanized environment.

Don’t stop me now, I’m having such a good time! Czechoslovakian wolfdogs renovate the motivation to play with a bow

Dogs engage in play behavior at every age and the play bow is their most iconic playful posture.However,the function of this posture is still under debate.Here,we selected the Czechoslovakian Wolfdog(CWD)as a model breed to clarify the function of the play bow.We analyzed frame-by-frame 118 sessions of 24 subjects and recorded 76 play bow events.We found that all the play bows were performed in the visual field of the playmate suggesting that the sender takes into account the attentional state of the receiver when releasing the signal.By drawing survival curves and using log-rank test we found that play bow was mainly performed during a short pause in an ongoing session and that its performance triggered the playmate’s reaction again.These findings show that play bow functions in restoring the partner motivation to play.Finally,by using a sequential analysis and a generalized mixed model,we found no evidence supporting the metacommunicative function of the play bow.The signal did not necessarily precede a contact offensive behavior(e.g.,play biting and play pushing)and it was not affected by the level of asymmetry of the play session.In conclusion,in CWDs play bow can be considered a visual signal useful to maintain the motivation to play in the receiver.Therefore,we suggest that the mismatched number of play bows emitted by the 2 players in a given session can be predictive of their different motivations to play.

Field assessment of dog as sentinel animal for plague in endemic foci of Madagascar

The epidemiology of Yersinia pestis,the causative agent of plague,involves vectors and reservoirs in its transmission cycle.The passive plague surveillance in Madagascar targets mainly rodent and fleas.However,carnivores are routinely surveyed as sentinels of local plague activity in some countries.The aim of this study is to assess the use of domestic dog(Canis familiaris)as sentinel animal for field surveillance of plague in a highly endemic area in Madagascar.Cross-sectional surveys of plague antibody prevalence in C.familiaris were conducted in endemic areas with contrasting histories of plague cases in humans,as well as a plague free area.Rodent capture was done in parallel to evaluate evidence for Y.pestis circulation in the primary reservoirs.In 2 sites,dogs were later re-sampled to examine evidence of seroconversion and antibody persistence.Biological samplings were performed between March 2008 and February 2009.Plague antibody detection was assessed using anti-F1 ELISA.Our study showed a significant difference in dog prevalence rates between plague-endemic and plague-free areas,with no seropositive dogs detected in the plague free area.No correlation was found between rodents and dog prevalence rates,with an absence of seropositive rodents in some area where plague circulation was indicated by seropositive dogs.This is consistent with high mortality rates in rodents following infection.Re-sampling dogs identified individuals seropositive on both occasions,indicating high rates of re-exposure and/or persistence of plague antibodies for at least 9 months.Seroconversion or seropositive juvenile dogs indicated recent local plague circulation.In Madagascar,dog surveillance for plague antibody could be useful to identify plague circulation in new areas or quiescent areas within endemic zones.Within active endemic areas,monitoring of dog populations for seroconversion(negative to positive)or seropositive juvenile dogs could be useful for identifying areas at greatest risk of human outbreaks.

Polyphony of domestic dog whines and vocal cues to body size

In domestic dogs Canis familiaris,vocal traits have been investigated for barks and growls,and the relationship between individual body size and vocal traits investigated for growls,with less corre-sponding information for whines.In this study,we examined the frequency and temporal traits of whines of 20 adult companion dogs(9 males,11 females),ranging in body mass from 3.5 to 70.0 kg and belonging to 16 breeds.Dog whines(26-71 per individual,824 in total)were recorded in condi-tioned begging contexts modeled by dog owners.Whines had 3 independent fundamental fre-quencies:the low,the high and the ultra-high that occurred singly as monophonic calls or simul-taneously as 2-voice biphonic or 3 voice polyphonic calls.From the smallest to largest dog,the upper frequency limit varied from 0.24 to 2.13 kHz for the low fundamental frequency,from 2.95 to 10.46 kHz for the high fundamental frequency and from 9.99 to 23.26 kHz for the ultra-high funda-mental frequency.Within individuals,the low fundamental frequency was lower in monophonic than in biphonic whines,whereas the high fundamental frequency did not differ between those whine types.All frequency variables of the low,high,and ultra-high fundamental frequencies cor-related negatively with dog body mass.For duration,no correlation with body mass was found.We discuss potential production mechanisms and sound sources for each fundamental frequency;point to the acoustic similarity between high-frequency dog whines and rodent ultrasonic calls and hypothesize that ultra-high fundamental frequencies function to allow private,"tete-a-tete"com-munication between members of social groups.

Dog sperm head morphometry： its diversity and .=volution

Dogs have been under strong artificial selection as a consequence of their relationship with man. Differences between breeds are evident that could be reflected in seminal characteristics. The present study was to evaluate differences in sperm head morphometry between seven well-defined breeds of dog： the British Bulldog, Chihuahua, German Shepherd, Labrador Retriever, Spanish Mastiff, Staffordshire Terrier, and Valencian Rat Hunting dog. Semen samples were obtained by masturbation and smears stained with Diff-Quik. Morphometric analysis （CASA-Morph） produced four size and four shape parameters. Length, Ellipticity, and Elongation showed higher differences between breeds. MANOVA revealed differences among all breeds. Considering the whole dataset, principal component analysis （PCA） showed that PC1 was related to head shape and PC2 to size. Procluster analysis showed the British Bulldog to be the most isolated breed, followed by the German Shepherd. The PCA breed by breed showed the Chihuahua, Labrador Retriever, Spanish Mastiff, and Staffordshire Terrier to have PC1 related to shape and PC2 to size, whereas the British Bulldog, Valencia Rat Hunting dog, and German Shepherd had PC1 related to size and PC2 to shape. The dendrogram for cluster groupings and the distance between them showed the British Bulldog to be separated from the rest of the breeds. Future work on dog semen must take into account the large differences in the breeds＇ sperm characteristics. The results provide a base for future work on phylogenetic and evolutionary studies of dogs, based on their seminal characteristics.

Effect of different starch sources in a raw meat-based diet on fecal microbiome in dogs housed in a shelter

A dietary intervention study was assessed to determine if different sources of starch in homemade diets could significantly modify fecal microbiome of dogs.Twenty-seven adult dogs were enrolled and fed a diet based on a mixture of rice and pasta with fresh raw meat(CD).After 90 d,8 dogs continued to receive CD diet,10 dogs received a diet made of a raw meat and a complementary food with rice as the main source of starch(B1),and 9 dogs were fed a diet with the same raw meat and a complementary food with potato as the main source of starch(B2).Samples of feces were collected from each dog in the mornings at the beginning of the study and after 15 d and analyzed for pH,ammonia N(N-NH3)and total N,short chain fatty acids(SCFA)and lactic acid.Relative abundance of fecal microbiota was assessed by sequencing and annotating the V3-V4 regions of the 16S rRNA.Total starch intake was similar between diets but differed in the in vitro rate digestion and in the resistant starch,which was higher in B2 than in B1 and CD diets.Dogs fed B2 diet showed lower(P<0.05)N-NH3 and pH but higher(P<0.05)molar proportion of lactic acid.Linear discriminant analysis of the genera relative abundances indicated a significant(P<0.01)increase of SMB53 genus at the end of the study in B1 diet and of Megamonas genus in B1 and B2 diets in comparison to CD diet.These results suggest that changes of starch source in a raw meat-based diet have limited effects on fecal microbiome in healthy dogs,but underline a high variability of microbiota among dogs.