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Full-Text Articles in Medicine and Health Sciences

Human Induced Rotation And Reorganization Of The Brain Of Domestic Dogs, Taryn Roberts, Paul Mcgreevy, Michael Valenzuela Jul 2010

Human Induced Rotation And Reorganization Of The Brain Of Domestic Dogs, Taryn Roberts, Paul Mcgreevy, Michael Valenzuela

Anatomy Collection

Domestic dogs exhibit an extraordinary degree of morphological diversity. Such breed-to-breed variability applies equally to the canine skull, however little is known about whether this translates to systematic differences in cerebral organization. By looking at the paramedian sagittal magnetic resonance image slice of canine brains across a range of animals with different skull shapes (N = 13), we found that the relative reduction in skull length compared to width (measured by Cephalic Index) was significantly correlated to a progressive ventral pitching of the primary longitudinal brain axis (r = 0.83), as well as with a ventral shift in the position …


Hair Whorls In The Dog (Canis Familiaris), Part Ii: Asymmetries, Lisa M. Tomkins, Paul Mcgreevy Mar 2010

Hair Whorls In The Dog (Canis Familiaris), Part Ii: Asymmetries, Lisa M. Tomkins, Paul Mcgreevy

Anatomy Collection

In horses and cattle, hair whorls have been shown to act as a structural marker of reactivity and behavioral lateralization. Few studies on canine whorls have been reported and none have assessed whorl position or direction of flow. This study describes the distribution and characteristics of whorl in each of 10 regions in which whorls are typically located in dogs. Hair whorls were assessed in dogs (n = 120) and were recorded as clockwise or counterclockwise in the cephalic, cervical (dorsal, lateral, ventral), thoracic and brachial axillary, chest, shoulders, elbows, abdominal, and ischiatic regions. Bilateral whorls, including brachial axillary, elbow, …


Hair Whorls In The Dog (Canisfamiliaris). I. Distribution, Lisa M. Tomkins, Paul Mcgreevy Feb 2010

Hair Whorls In The Dog (Canisfamiliaris). I. Distribution, Lisa M. Tomkins, Paul Mcgreevy

Anatomy Collection

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). …


Cetacean Brains: How Aquatic Are They?, Lori Marino Jun 2007

Cetacean Brains: How Aquatic Are They?, Lori Marino

Anatomy Collection

The adaptation of cetaceans to a fully aquatic lifestyle represents one of the most dramatic transformations in mammalian evolutionary history. Two of the most salient features of modern cetaceans are their fully aquatic lifestyle and their large brains. This review article will offer an overview of comparative neuroanatomical research on aquatic mammals, including analyses of odontocete cetacean, sirenian, pinniped, and fossil archaeocete brains. In particular, the question of whether a relationship exists between being fully aquatic and having a large brain is addressed. It has been hypothesized that the large, well‐developed cetacean brain is a direct product of adaptation to …


Cetaceans Have Complex Brains For Complex Cognition, Lori Marino, Richard C. Connor, R. Ewan Fordyce, Louis M. Herman, Patrick R. Hof, Louis Lefebvre, David Lusseau, Brenda Mccowan, Esther A. Nimchinsky, Adam A. Pack, Luke Rendell, Joy S. Reidenberg, Diana Reiss, Mark D. Uhen, Estel Van Der Gucht, Hal Whitehead May 2007

Cetaceans Have Complex Brains For Complex Cognition, Lori Marino, Richard C. Connor, R. Ewan Fordyce, Louis M. Herman, Patrick R. Hof, Louis Lefebvre, David Lusseau, Brenda Mccowan, Esther A. Nimchinsky, Adam A. Pack, Luke Rendell, Joy S. Reidenberg, Diana Reiss, Mark D. Uhen, Estel Van Der Gucht, Hal Whitehead

Anatomy Collection

We believe that the time is ripe to present an integrated view of cetacean brains, behavior, and evolution based on the wealth of accumulated and recent data on these topics. Our conclusions support the more generally accepted view that the large brain of cetaceans evolved to support complex cognitive abilities.


Cetacean Brain Evolution: Multiplication Generates Complexity, Lori Marino Dec 2004

Cetacean Brain Evolution: Multiplication Generates Complexity, Lori Marino

Anatomy Collection

Over the past 55-60 million years cetacean (dolphin, whale, and porpoise) brains have become hyperexpanded so that modern cetacean encephalization levels are second only to modern humans. At the same time, brain expansion proceeded along very different lines than in other large-brained mammals so that substantial differences between modern cetacean brains and other mammalian brains exist at every level of brain organization. Perhaps the most profound difference between cetacean and other mammalian brains is in the architecture of the neocortex. Cetaceans possess a unique underlying neocortical organizational scheme that is particularly intriguing in light of the fact that cetaceans exhibit …


An Attempt To Estimate Teat Quality Of Sows By Hand Milking During Farrowing, D. Fraser, C. S. Lin Mar 1984

An Attempt To Estimate Teat Quality Of Sows By Hand Milking During Farrowing, D. Fraser, C. S. Lin

Anatomy Collection

For 21 sows, teats were hand milked individually in a standard way during farrowing in an attempt to produce an index of teat quality. The piglets' teat selection and 14-day weights were then compared with the hand milking results. Of within-litter variation in 14-day weight, 38.67% was explained by 1-day weight, and only 4.6% extra variation by the index derived from hand milking. Use of the index gave no improvement over previous models involving 1-day weight and teat number (anterior to posterior). Hand milking showed a pronounced decline in colostrum yield from the most anterior teat pair (46.8 g) to …