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Animal Sciences Commons

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Articles 1 - 4 of 4

Full-Text Articles in Animal Sciences

Environmental Physiology Of Flight In Migratory Birds, Alexander R. Gerson Aug 2012

Environmental Physiology Of Flight In Migratory Birds, Alexander R. Gerson

Electronic Thesis and Dissertation Repository

Migratory birds complete amazing journeys between their breeding and wintering grounds. Each journey comprises a series of flights that last hours to days, followed by stopovers where fuel stores are replenished. Despite the long flights undertaken by migratory birds, where respiratory water losses are high for extended periods of time, birds are not dehydrated after flight. My studies demonstrate that birds maintain hydration by modulating rates of endogenous water production in response to rates of water loss. In resting, water restricted house sparrows (Passer domesticus) I used quantitative magnetic resonance body composition analysis (QMR) and hygrometry to demonstrate that stressed …


Changes In The Mitochondrial Phosphoproteome During Mammalian Hibernation, Dillon J. Chung Jul 2012

Changes In The Mitochondrial Phosphoproteome During Mammalian Hibernation, Dillon J. Chung

Electronic Thesis and Dissertation Repository

Hibernation in mammals involves a suppression of metabolic rate thereby conserving energy. Many hibernation studies focus on the mitochondria due to their energy-producing role. I hypothesized that this pattern of rapid suppression of liver mitochondrial metabolism with gradual reversal, was related to changes in the phosphorylation state of Ictidomys tridecemlineatus’ mitochondrial proteins in different stages of torpor bouts. Phosphorylation of threonine and serine amino-acid residues (unique to 49, 41 and 47, 38 kDa proteins respectively), detected using immunoblotting, changes seasonally (threonine: summer active > winter, serine: summer active > torpor), whereas no seasonal difference was observed in phosphotyrosine residues. Changes in …


Dynamics Of Fat And Lean Mass In Refuelling Migrant Passerines Measured Using Quantitative Magnetic Resonance, Lisa V. Kennedy Apr 2012

Dynamics Of Fat And Lean Mass In Refuelling Migrant Passerines Measured Using Quantitative Magnetic Resonance, Lisa V. Kennedy

Electronic Thesis and Dissertation Repository

Although fat deposition during stopover in migrating passerine birds has been extensively studied, changes in lean mass during refuelling are not well understood. I used quantitative magnetic resonance (QMR) analysis to measure the deposition of fat and lean mass for both recaptured and single capture migrant passerines in spring and fall at Long Point, Ontario. Both the recapture analysis and single capture regression analysis indicated a substantial contribution of lean mass to overall increases in total body mass. Some of the variation in the relative deposition of fat and lean mass was explained by sex, age and season. I then …


Introduced Chinook Salmon (Oncorhynchus Tshawytscha) In Lake Huron: Do They Spawn At The Right Time?, Meghan T. Gerson Apr 2012

Introduced Chinook Salmon (Oncorhynchus Tshawytscha) In Lake Huron: Do They Spawn At The Right Time?, Meghan T. Gerson

Electronic Thesis and Dissertation Repository

Chinook salmon (Oncorhynchus tshawytscha), following their introduction to the Great Lakes, have successfully colonized many tributaries. Under the hypothesis that colonization success is facilitated by intrinsic factors (i.e., preadaptation), I predicted that patterns of reproductive timing in an introduced population would show similarities with those in their native range. To test this prediction, attributes of reproductive timing were characterized in Chinook salmon from the Sydenham River, Ontario. In their native range, female Chinook salmon exhibit a seasonal decline in reproductive lifespan, a decline in fat stores, low egg retention at death (< 0.5%), and spawning at temperatures below 12.8°C. In contrast, Sydenham River Chinook salmon showed no seasonal decline in reproductive lifespan or fat stores and nineteen of twenty females had egg retention greater or equal to 0.5%. Also, many individuals (30%) spawned when water temperatures exceeded 12.8°C. Thus, individuals do not appear to be pre-adapted in this system.