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Full-Text Articles in Animal Sciences
Post-Effect Of Ammonia On Energetics Of Laying Hens At High Temperatures, Hongwei Xin, James A. Deshazer, M. M. Beck
Post-Effect Of Ammonia On Energetics Of Laying Hens At High Temperatures, Hongwei Xin, James A. Deshazer, M. M. Beck
Hongwei Xin
Leghorn layers were monitored for heat loss, feed intake, egg production and respiratory rate at various environmental temperatures (TJ after first being exposed to aerial ammonia (NH3). The initial exposure was to 10 or 60 ppm NH3 at a T, of 25 °C for 30 days to simulate a winter environmental condition in a poultry facility. Hens were then allowed to recover in an environment of 5 ppm of NH3 at a T^ of 22 °C for seven days to simulate a spring environmental condition. Birds were then placed individually in a partitional calorimeter free of NH3 at 25, 29, …
Uptake And Internal Distribution Of Exogenously Supplied Amino Acids In The Pacific Oyster, Crassostrea Gigas (Thunberg), Michael A. Rice, Grover C. Stephens
Uptake And Internal Distribution Of Exogenously Supplied Amino Acids In The Pacific Oyster, Crassostrea Gigas (Thunberg), Michael A. Rice, Grover C. Stephens
Michael A Rice
A technique is described in which irrigation of the mantle cavity of oysters, Crassostrea gigas, induces pumping at steady rates. Simultaneous net influx of 10 amino acids (asp, glu, asn, ser, gly, tau, ala, val, phe, lys) is observed by high-performance liquid chromatography (HPLC). Individual amino acids exhibit first-order exponential depletion from an initial medium concentration of 2.0 μM. Influx of radiolabeled alanine corresponds very closely to net entry of alanine as estimated by HPLC. Therefore, net entry of alanine from dilute solution (5 μM) occurs. The entry of alanine is well described by Michaelis-Menten kinetics with a maximum influx …
Thermal Constraints On Foraging Activity Of Adult Starlings, Larry Clark
Thermal Constraints On Foraging Activity Of Adult Starlings, Larry Clark
Larry Clark
The operative temperature of the environment was estimated for starlings using hollow, unheated taxidermic mounts. On average, adults foraging in full sun were characterized by shorter foraging bouts than those adults foraging in full shade. Simultaneous observations of air temperature, operative temperature, and the foraging duration of adults indicated that air temperature was a poor predictor of the maximum length of a foraging bout. The operative temperature of the environment was not correlated to the maximum and mean length of foraging bouts for temperatures below 31.5 ~ C, but was negatively related to maximum and mean foraging duration for values …
Olfactory Discrimination Of Plant Volatiles By The European Starling, Larry Clark, J Russell Mason
Olfactory Discrimination Of Plant Volatiles By The European Starling, Larry Clark, J Russell Mason
Larry Clark
Passerine species that re-use nest sites often incorporate fresh green vegetation into their nests, a behaviour consistent with the possibility that some birds may use chemical properties of plants to counteract the selective potential of parasites and pathogens. We tested adult starlings (Sturnus vulgaris) for their physiological capacity and behavioural ability to detect and discriminate between volatiles emitted from plant material. Multi-unit electrophysiological recordings from olfactory nerves of adults indicated that strong responses were reliably elicited by volatiles from six plant species. After pairings of plant volatiles with gastro-intestinal malaise, birds exhibited conditioned avoidance in behavioural experiments, and made all …
Degree Of Behavioral Neoteny Differentiates Canid Polymorphs, R Coppinger, J. Glendinning, E. Torop, C. Matthay, M. Sutherland, C. Smith
Degree Of Behavioral Neoteny Differentiates Canid Polymorphs, R Coppinger, J. Glendinning, E. Torop, C. Matthay, M. Sutherland, C. Smith
Charles Kay Smith
As with juvenile wolves or coyotes, adult livestock conducting dogs displayed the first-half segment of a functional predatory system of motor patterns and did not express play or social bonding toward sheep; whereas, like wolf or coyote pups, adult livestock protecting dogs displayed sequences of mixed social, submissive, play and investigatory motor patterns and rarely expressed during ontogeny (even when fully adult) predatory behaviors. The most parsimonious explanation of our findings is that behavioral differences in the two types of livestock dogs are a case of selected differential retardation (neoteny) of ancestral motor pattern development.