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1.  Simulating Free-Roaming Cat Population Management Options in Open Demographic Environments 
PLoS ONE  2014;9(11):e113553.
Large populations of free-roaming cats (FRCs) generate ongoing concerns for welfare of both individual animals and populations, for human public health, for viability of native wildlife populations, and for local ecological damage. Managing FRC populations is a complex task, without universal agreement on best practices. Previous analyses that use simulation modeling tools to evaluate alternative management methods have focused on relative efficacy of removal (or trap-return, TR), typically involving euthanasia, and sterilization (or trap-neuter-return, TNR) in demographically isolated populations. We used a stochastic demographic simulation approach to evaluate removal, permanent sterilization, and two postulated methods of temporary contraception for FRC population management. Our models include demographic connectivity to neighboring untreated cat populations through natural dispersal in a metapopulation context across urban and rural landscapes, and also feature abandonment of owned animals. Within population type, a given implementation rate of the TR strategy results in the most rapid rate of population decline and (when populations are isolated) the highest probability of population elimination, followed in order of decreasing efficacy by equivalent rates of implementation of TNR and temporary contraception. Even low levels of demographic connectivity significantly reduce the effectiveness of any management intervention, and continued abandonment is similarly problematic. This is the first demographic simulation analysis to consider the use of temporary contraception and account for the realities of FRC dispersal and owned cat abandonment.
PMCID: PMC4245120  PMID: 25426960
2.  Age relationships of postmortem observations in Portuguese Water Dogs 
Age  2010;33(3):461-473.
A dog model has been used to evaluate histological changes arising from senescence. Autopsies of 145 Portuguese Water Dogs have been used to evaluate the individual and group “state of health” at time of death. For each dog, weights or dimensions of organs or tissues were obtained, together with histological evaluation of tissues. Twenty-three morphological metrics correlated significantly to age at death. Many of these involved muscles; others were associated with derivatives of embryonic foregut. The latter included lengths of the small intestine and trachea as well as weights of the stomach and some lung lobes. Nearly all of the dogs examined had histological changes in multiple tissues, ranging from two to 12 per dog. Associations among pathologies included inflammatory bowel disease with osteoporosis and dental calculus/periodontitis with atherosclerosis and amyloidosis. In addition, two clusters of histological changes were correlated to aging: hyperplasia, frequency of adenomas, and hemosiderosis constituted one group; inflammation, plasmacytic and lymphocytic infiltration, fibrosis, and atrophy, another. Heritability analysis indicated that many of the changes in tissue/organ morphology or histology could be heritable and possibly associated with IGF1, but more autopsies will be required to substantiate these genetic relationships.
Electronic supplementary material
The online version of this article (doi:10.1007/s11357-010-9181-5) contains supplementary material, which is available to authorized users.
PMCID: PMC3168605  PMID: 20845083
Age of death; Autopsy; Dog; Pathology; Histology
3.  A Single IGF1 Allele Is a Major Determinant of Small Size in Dogs 
Science (New York, N.Y.)  2007;316(5821):112-115.
The domestic dog exhibits greater diversity in body size than any other terrestrial vertebrate. We used a strategy that exploits the breed structure of dogs to investigate the genetic basis of size. First, through a genome-wide scan, we identified a major quantitative trait locus (QTL) on chromosome 15 influencing size variation within a single breed. Second, we examined genetic variation in the 15-megabase interval surrounding the QTL in small and giant breeds and found marked evidence for a selective sweep spanning a single gene (IGF1), encoding insulin-like growth factor 1. A single IGF1 single-nucleotide polymorphism haplotype is common to all small breeds and nearly absent from giant breeds, suggesting that the same causal sequence variant is a major contributor to body size in all small dogs.
PMCID: PMC2789551  PMID: 17412960
4.  Bilaterally Asymmetric Effects of Quantitative Trait Loci (QTLs): QTLs That Affect Laxity in the Right Versus Left Coxofemoral (Hip) Joints of the Dog (Canis familiaris) 
In dogs hip joint laxity that can lead to degenerative joint disease (DJD) is frequent and heritable, providing a genetic model for some aspects of the human disease. We have used Portuguese water dogs (PWDs) to identify Quantitative trait loci (QTLs) that regulate laxity in the hip joint.A population of 286 PWDs, each characterized by ca. 500 molecular genetic markers, was analyzed for subluxation of the hip joint as measured by the Norberg angle, a quantitative radiographic measure of laxity. A significant directed asymmetry was observed, such that greater laxity was observed in the left than the right hip. This asymmetry was not heritable. However, the average Norberg angle was highly heritable as were the Norberg angles of either the right or left hips. After correction for pedigree effects, two QTLs were identified using the metrics of the left and right hips as separate data sets. Both are on canine chromosome 1 (CFA1), separated by about 95 Mb. One QTL, associated with the SSR marker FH2524 was significant for the left, but not the right hip. The other, associated with FH2598, was significant for the right but not the left hip. For both QTLs, some extreme phenotypes were best explained by specific interactions between haplotypes.
PMCID: PMC2778498  PMID: 14708095
quantitative trait loci (QTLs); dog; hip laxity; bilateral asymmetry; Norberg angle; Canine genetics; hip dysplasia
6.  Exploring human/animal intersections: Converging lines of evidence in comparative models of aging 
At a symposium convened on March 8, 2007 by the Institute on Aging at the University of Pennsylvania, researchers from the University’s Schools of Medicine and Veterinary Medicine explored the convergence of aging research emerging from the two schools. Studies in human patients, animal models, and companion animals have revealed different but complementary aspects of the aging process, ranging from fundamental biologic aspects of aging to the treatment of age-related diseases, both experimentally and in clinical practice. Participants concluded that neither animal nor human research alone will provide answers to most questions about the aging process. Instead, an optimal translational research model supports a bidirectional flow of information from animal models to clinical research.
PMCID: PMC2665932  PMID: 18631944
Organ specific mechanisms of aging in humans and animals; Model systems for aging research; Normal aging; Aging related diseases

Results 1-6 (6)