Matching Items (13)
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- All Subjects: Dogs
- Creators: Wynne, Clive
- Creators: Tollis, Marc
Description
Due to artificial selection, dogs have high levels of phenotypic diversity, yet, there appears to be low genetic diversity within individual breeds. Through their domestication from wolves, dogs have gone through a series of population bottlenecks, which has resulted in a reduction in genetic diversity, with a large amount of linkage disequilibrium and the persistence of deleterious mutations. This has led to an increased susceptibility to a multitude of diseases, including cancer. To study the effects of artificial selection and life history characteristics on the risk of cancer mortality, we collected cancer mortality data from four studies as well as the percent of heterozygosity, body size, lifespan and breed group for 201 dog breeds. We also collected specific types of cancer breeds were susceptible to and compared the dog cancer mortality patterns to the patterns observed in other mammals. We found a relationship between cancer mortality rate and heterozygosity, body size, lifespan as well as breed group. Higher levels of heterozygosity were also associated with longer lifespan. These results indicate larger breeds, such as Irish Water Spaniels, Flat-coated Retrievers and Bernese Mountain Dogs, are more susceptible to cancer, with lower heterozygosity and lifespan. These breeds are also more susceptible to sarcomas, as opposed to carcinomas in smaller breeds, such as Miniature Pinschers, Chihuahuas, and Pekingese. Other mammals show that larger and long-lived animals have decreased cancer mortality, however, within dog breeds, the opposite relationship is observed. These relationships could be due to the trade-off between cellular maintenance and growing fast and large, with higher expression of growth factors, such as IGF-1. This study further demonstrates the relationships between cancer mortality, heterozygosity, and life history traits and exhibits dogs as an important model organism for understanding the relationship between genetics and health.
ContributorsBalsley, Cassandra Sierra (Author) / Maley, Carlo (Thesis director) / Wynne, Clive (Committee member) / Tollis, Marc (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Dogs' health and wellbeing is of great importance to their owners. The most common nutritional problem for pet dogs is obesity, with 22-40% of pet dogs being classified as overweight or obese. With many adverse health effects associated with obesity, this is a major concern for owners and veterinarians. The degree to which dogs enjoy consuming certain foods can have substantial implications for their body weight, so it is important to understand which aspects of foods make them appealing to dogs. This study aimed to determine whether nutritional aspects of commercial dog foods predict dogs' preferences for those foods. It was found that consumption preference is positively correlated with protein content (p < .001), therefore implying that the protein content of commercial dry dog foods may predict dogs' consumption preferences. Consumption preferences were not predicted by other available measures of food content or caloric value. Dogs' preference for foods high in protein content may be due to the satiating effect of protein. Since foods high in protein both reduce the amount of energy consumed and are found to be palatable to dogs, high-protein dog foods may offer a way for dog food manufacturers, veterinarians, and pet owners to combat obesity in pet dogs.
ContributorsPrevost, Emily Danielle (Author) / Wynne, Clive (Thesis director) / Hall, Nathaniel (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Brief memory tasks for use with pet dogs were developed using radial arm maze performance as a standard comparison measurement of memory capacity. Healthy pet dogs were first tested in a radial arm maze, where more errors made in completing the maze indicated poorer memory. These dogs were later tested with five novel memory tests, three of which utilized a treat placed behind a box with an identical distracter nearby. The treat placement was shown to each dog, and a 35 second delay, a 15 second delay with occluder, or a 15 second delay with room exit was observed before the dog could approach and find the treat. It was found that errors on the delayed match to sample (35 second delay) and occluder/object permanence (15 second delay with occluder) tasks were significantly positively correlated with the average number of errors made in the 8th trial of the radial arm maze (r =.58, p<.01** and r =.49, p<.05*, respectively) indicating that these new brief tests can reliably be used to assess memory in pet dogs.
ContributorsBoileau, Rae Nicole (Author) / Wynne, Clive (Thesis director) / Knight, George (Committee member) / Bimonte-Nelson, Heather (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor)
Created2015-05
Description
There are many anecdotal stories of dogs rescuing their owners from dangerous situations, but this rescue behavior has yet to be shown in an experimental setting. Studies have shown that dogs behave differently towards crying humans, but do not seek help for their owners when they are in distress. This study sought to determine if a dog could recognize when its owner was in distress and would attempt to rescue the owner. The experiment consisted of three conditions: a distress condition to determine how dogs respond to an owner calling for help, a reading condition to control for proximity-seeking and sound, and a food control to use as a basis for motivation and door-opening ability of the dog. Sixty dogs were tested in all three conditions in a pseudo-random order so that an equal number of dogs completed the conditions in each order. 38% of the dogs opened the apparatus for any condition, while 32% opened for the food and distress conditions and 27% opened for the reading condition, which shows that rescue in general is unlikely. There was no significant difference in the proportion of dogs who opened the apparatus for each condition, indicating that dogs are no more likely to rescue their distressed owners than they are to open the apparatus for other conditions and may not be able to sense that the owner is in distress. The similarities in the success rates also show that the owner can be just as motivating for a dog as food. Overall, the low success rates suggest that dogs are not generally likely to rescue a person who is trapped, even when they are calling for help.
ContributorsPatterson, Jordan Elizabeth (Author) / Wynne, Clive (Thesis director) / McBeath, Michael (Committee member) / W.P. Carey School of Business (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Previous research pertaining to dog memory and cognition has been confined mainly to samples of colony dogs and therefore can be hard to generalize to a larger population of pet dogs and varying breeds. The present study focused entirely on pet dogs of many different breeds, rather than colony or laboratory animals for the purposes of accessibility, affordability, and novelty. Methods: We presented the dogs with a memory task in the form of a game in which the dogs chose to search for food at one of two locations at varying delay intervals, with a maximum time limit of one hour per dog. We expected our data to show a significant decrease in memory capacity and an increase in error rates among older dogs as compared to younger dogs; these results would allow us to conclude that it is likely many dogs, much like humans, experience various cognitive deficits as a function of increasing age. Results: Using one-factor ANOVA and linear and curvilinear regression analyses, we examined the relationship between the independent variable, age (individual dog ages as well as three generalized age categories), and three dependent variables. The dependent variables were: (a) percentage of correct choices at a 60 second delay interval, (b) maximum delay interval attempted (MDIA), and (c) the maximum delay interval that was completed above chance level (50%) (MDAC). We found significant results to support our hypotheses that aged dogs show spatial memory and cognitive deficits in comparison with young and middle-aged dogs, and that age can be considered a marginally significant predictor of spatial memory capacity.
ContributorsEvans, Laura Corinne (Author) / Wynne, Clive (Thesis director) / Van Bourg, Joshua (Committee member) / Glenberg, Arthur (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
We compared sociability towards humans of domesticated and tame members of several Canidae: Belyaev's fox (Vulpes vulpes), red fox (Vulpes vulpes), gray wolf (Canis lupus), dingo (Canis l. dingo), New Guinea singing dog (Canis l. dingo), and dog (Canis l. familiaris). We defined sociability as motivation or willingness to engage with humans. Our operationalized definition of sociability is the latency to approach (LTA) the human experimenter and the amount of time the canid spent within one meter of the human experimenter (PTC). We added an unfamiliar and familiar experimenter condition to deduce whether or not canids discriminated on who they were more social with: an owner or a stranger. To each experimenter condition we added a passive and active phase to discern whether or not canids were more social when called or not. Across all conditions and phases dogs were significantly more social than all other canid types. We concluded genetic differences due to domestication and environmental differences due to socialization accounted for sociability differences seen in dogs compared to the other canid types.
ContributorsBeckstrom-Sternberg, David Tristan (Author) / Wynne, Clive (Thesis director) / McBeath, Michael (Committee member) / School of International Letters and Cultures (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Alzheimer's disease affects a large number of Americans every year, and research on the causes and possible prevention continues to increase. Alzheimer's disease is a form of dementia that causes problems with memory, thinking, and behavior and is thought to be caused by beta-amyloid plaques that form in the brain. In recent years, dogs have been used more and more as an animal model looking at Alzheimer's disease and cognitive dysfunction. Dogs serve as a reliable animal model because effected dogs naturally form the same beta-amyloid plaques that affected humans do as they age. Previous research has shown that older dogs perform worse on various memory tasks than do younger dogs, however researchers have struggled to find a test for dog cognitive dysfunction that is brief and can be performed in the home. The current study aimed to find a brief memory task that requires few materials, but is still reliable. The results of this study do not support the hypothesis that older dogs would perform worse than younger dogs if tested to find a treat with varying time delays of 15, 30, and 45 seconds. The results of this experiment showed a main effect of age (F = 8.40, d.f. 1, 19, p < 0.01) and delay (F = 15.14, d.f. 2, 30, p < 0.01), but age-delay interaction was not significant (F = 2.53, d.f. 2, 30, p = 0.09). Future studies should be performed using a larger sample size and this same protocol to attempt to raise the participation level of the dogs.
ContributorsZimmerman, Megan Renee (Author) / Wynne, Clive (Thesis director) / Bimonte-Nelson, Heather (Committee member) / Department of Psychology (Contributor) / W. P. Carey School of Business (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
A handheld metal cricket noisemaker known as a "clicker" is often used in dog training to teach dogs new behaviors; however, evidence for the superior efficacy of clickers as opposed to providing solely primary reinforcement or other secondary reinforcers in the acquisition of novel behavior in dogs is almost entirely anecdotal. We sought to determine under what circumstances a clicker may result in acquisition of a novel behavior to a higher level when compared to other potential reinforcement methods. In Experiment 1, three groups of 30 dogs each were trained to emit a novel sit and stay behavior with either the delivery of food alone, a verbal marker with food, or a clicker and food. The group that received only a primary reinforcer reached a significantly higher criterion of training than the group trained with a verbal secondary reinforcer. Performance of the group experiencing a clicker secondary reinforcer was intermediate between the other two groups, but not significantly different from either. In Experiment 2, three different groups of 25 dogs each were shaped to emit a nose targeting behavior and then perform that behavior at increasing distances from the experimenter using the same three methods of positive reinforcement used in Experiment 1. No statistically significant differences between the groups were found. Overall, the findings suggest that both clickers and other forms of positive reinforcement can be used successfully in training a dog to perform a novel behavior.
ContributorsGilchrist, Rachel (Author) / Wynne, Clive (Thesis director) / Conrad, Cheryl (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Dogs in animal shelters are subjected to a number of stressors during their stay, including barking which can reach 120 dB. Music has been suggested as a way to reduce this stress, however, the properties of music that result in reduced stress behavior have not been examined. An affective response to music, like that found in humans, is unlikely due to human higher cognitive function. Masking, reducing the magnitude of volume change with the presence of another sound, is one property that may be responsible for this observed stress reduction. Using white and pink noise, we examined the effects of auditory masking on stress behaviors in shelter dogs. Overall, we observed no difference in the amount of sitting, lying, head resting, or barking between the control and treatment conditions. Limitations and future directions of studies are listed.
ContributorsRedmond, Domenic Xavier Wendell (Author) / Wynne, Clive (Thesis director) / Glenberg, Arthur (Committee member) / Steele, Kenneth (Committee member) / School of Social Transformation (Contributor) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
This study was conducted in order to create a brief task that more efficiently studies the memory of young and old dogs compared to previous dog radial arm mazes. The hypotheses were older dogs would perform worse than younger dogs, brief tasks with longer delays and the presence of an occluder would produce worse results, and the brief task with the longest delay period without an occluder would be most correlated to the radial arm maze. 45 dogs were tested from a previous sample that had participated in a radial arm maze experiment. The dogs were tested in their owner's homes and watched the researcher place a treat behind one of two boxes. Dogs then waited during different delay periods, of 15, 30, or 45 seconds, and with or without an occluder, which was a curtain. Then, the dog was released to see if it could still remember which box the treat was behind. The results supported all the hypotheses, except the 45-second brief task with an occluder was most correlated the radial arm maze. Additionally, the dogs that had to be excluded from the radial arm maze still had a similar range of results on the brief tasks as dogs that were able to complete the radial arm maze. These results confirm the radial arm maze is very difficult and strenuous on dogs, but the brief task is correlated and probably much more effective at studying memory without these issues. This study can help researchers perfect this simple task in order to study many dogs much quicker and collect more information on dogs' memory. Future studies could overcome limitations including dogs that were not motivated by treats or that were too old to stand up. Specific breeds could be tested or longitudinal studies could be conducted to find differences in memory over time. In the future, this can hopefully relate to human cognitive decline knowledge, as dogs show similar cognitive decline to humans, and help find treatments for cognitive diseases.
ContributorsGlomski, Marissa (Author) / Wynne, Clive (Thesis director) / Presson, Clive (Committee member) / Brewer, Gene (Committee member) / Department of Psychology (Contributor) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12