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Variety Of Breeds (variety + of_breed)
Selected AbstractsHair Whorls in the Dog (Canis familiaris).THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 2 2010Abstract Hair whorl characteristics were assessed in the domestic dog (Canis familiaris) in the regions of cephalic, cervical (dorsal, ventral, and lateral), thoracic and brachial axillary regions, the chest, shoulders, elbows, ventral abdominal region, and on the caudal thighs (ischiatic). They were classified as simple or tufted, and their position was recorded as the distance between their centers and bony landmarks within each region. The distribution of whorls was explored in a cohort of domestic dogs (N = 120) comprising a variety of breeds and cross-breeds, sourced from shelters (N = 60) and the general public (N = 60). Whorls observed in the majority of dogs in this cohort typically occurred on the chest, brachial axillary region, elbows, and ischiatic region. Atypical whorls were present in fewer than 20% of the population, and included those on the head (cephalic), cervical regions (dorsal, ventral, and lateral), shoulders, thoracic axillary region, and on the ventral abdominal region. The majority of whorls on dogs were classified as simple. In contrast, those located on the elbows and the majority of chest whorls were tufted. The presence and position of whorls were often associated with several variables including coat length and thickness, and the sex and source of the dog. The palpation and hair-cluster method of whorl assessment described in this article is best suited to dogs with short-to-medium coat lengths. The current methodology developed to assess hair whorl characteristics provides a framework for future investigations into any associations between hair whorl characteristics and other canine traits such as temperament. Anat Rec, 293:338,350, 2010. © 2010 Wiley-Liss, Inc. [source] The Distribution of Ganglion Cells in the Equine Retina and its Relationship to Skull MorphologyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2007K. E. Evans Summary It has recently been reported that a strong correlation exists between the distribution of retinal ganglion cells and nose length in the domestic dog. To determine if this phenomenon occurs in another domestic species with diverse skull morphology, the current study examined the distribution of retinal ganglion cells in 30 horses from a variety of breeds. There was a significant variation in the density of ganglion cells found across the retinae. Breed was a significant predictor for ganglion cell density within the visual streak. A strong positive correlation exists between the density of ganglion cells in the visual streak and nasal length. Significant variation was also seen in the area centralis but did not correlate with any of the recorded skull measurements. The findings of this study provide us with further understanding of the equine visual system and the level of variation that exists between individuals of the same species. [source] Conformation of the Equine Skull: A Morphometric StudyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2006K. E. Evans Summary There is a lack of an established method for quantifying equine skull morphology. This study proposes a method that is valid for use on both live and deceased horses. A total of nine head measurements (skull length, cranial length, nasal length, ratio of cranial:nasal length, cranial width, zygomatic width, mandibular depth, nasal profile area, cranial profile area) and six indices (skull index, cranial index, nasal index, mandibular index, nasal profile index, cranial profile index) were recorded from 30 horses from a variety of breeds whilst the soft tissues of the head were intact. A line was drawn level with the palpable notches caudal to the caudal lacrimal process of each orbit to estimate the suture line of the nasal and frontal bones and distinguish between the neurocranium and splanchnocranium. There were positive correlations between many of the head measurements. This method also illustrated significant differences in the skull morphology of three breeds (Arabians, thoroughbreds and standardbreds). [source] Identification of a novel germline MET mutation in dogsANIMAL GENETICS, Issue 3 2006A.T. Liao Summary The MET proto-oncogene encodes a transmembrane tyrosine kinase receptor that mediates multiple functions such as migration, cycling and survival by binding to hepatocyte growth factor (HGF). Dysregulation of MET through inappropriate expression or mutation has been shown to play an important role in human cancers. Furthermore, inherited mutations in MET are known to contribute to the development of gastric and renal cancer in humans. Lastly, mouse models of MET mutations lead to the development of a wide variety of cancers including lymphomas, sarcomas and some forms of carcinoma. In the process of cloning canine MET, a novel germline point mutation was found in the juxtamembrane domain (G966S) in two of the templates used for cloning, both of which were derived from Rottweiler dogs, a breed believed to be at high risk for the development of several cancers. Screening of germline DNA from a variety of breeds revealed that this mutation was present in approximately 70% of Rottweiler dogs and <5% of all other breeds examined, suggesting a breed-specific heritable mutation. Stable transfection of the G966S mutant form of MET into NIH3T3 cells resulted in enhanced baseline scattering and migration of the cells, which was further increased in the presence of HGF. This study supports the notion that particular dog breeds may carry germline mutations that contribute to high rates of cancer in a manner similar to heritable, cancer-associated mutations in humans. [source] |