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Articles 1 - 12 of 12

Full-Text Articles in Life Sciences

Nutritive And Nonnutritive Sucking And The Temporal Organization Of The Suckling Behavior Of Domestic Piglets, Jeffrey Rushen, David Fraser Dec 1989

Nutritive And Nonnutritive Sucking And The Temporal Organization Of The Suckling Behavior Of Domestic Piglets, Jeffrey Rushen, David Fraser

Feeding Behavior Collection

Detailed video recordings of the suckling behavior of one piglet from each of four litters were analyzed to determine how the components of piglet suckling behavior are organized in relation to the time of milk ejection and the temporal pattern of grunting by the sow. Early in the suckling episode, most piglets massaged the udder with their snouts, and then changed gradually to sucking the teats with slow mouth movements (1-2/sec). The piglets then had a distinct phase of sucking with rapid mouth movements (4-5/sec) which began suddenly and lasted about 5 to 15 sec. The weight gains of piglets …


Population And Social Biology Of Free-Ranging Dogs, Canis Familiaris, Thomas J. Daniels, Marc Bekoff Nov 1989

Population And Social Biology Of Free-Ranging Dogs, Canis Familiaris, Thomas J. Daniels, Marc Bekoff

Ecology Collection

Population size and density, age structure, survivorship patterns, sex ratios, social organization of urban, rural, and feral dog (Canis familiaris) populations were examined in Cd. Juarez, Mexico (urban site) and on the Navajo reservation (rural and wild sites) between June 1983 and December 1984. Urban and rural dogs were less social than expected whereas dogs characteristically lived in packs. Seasonal variation in the structure of feral dog packs influenced by reproduction, both directly (pups born into the pack) and indirectly (pregnant females may temporarily emigrate form the pack to give birth).


Fur Is Out, Compassion Is In Oct 1989

Fur Is Out, Compassion Is In

Close Up Reports

HSUS campaign targets consumers


Remember The Elephants ... Forget Ivory Jul 1989

Remember The Elephants ... Forget Ivory

Close Up Reports

No abstract provided.


Animal Companions--The Promise Kept; The Problems Broken May 1989

Animal Companions--The Promise Kept; The Problems Broken

Close Up Reports

The powerful bond between people and dogs and cats is accompanied by serious ethical obligations on our part.


Specificity Of The Cardiac Response To Conspecific Vocalizations In Chimpanzees, Gary G. Berntson, Sarah T. Boysen Apr 1989

Specificity Of The Cardiac Response To Conspecific Vocalizations In Chimpanzees, Gary G. Berntson, Sarah T. Boysen

Sentience Collection

Heart rate measures were used to examine the functional response of young chimpanzees and orangutans to acoustic stimuli, including white noise and chimpanzee vocalizations (threat, stress, and alarm). The initial response of the animals to all stimuli was characterized by a prominent cardiac deceleration and an increase in heart period variability. The deceleratory responses persisted with repeated presentations of the noise, stress, and alarm stimuli. In contrast, the response of chimpanzees to the conspecific threat stimulus reverted over trials to a notable cardiac acceleration. This acceleratory response was not attributable to potential patterns of evoked somatic responses. The features of …


Numerical Competence In A Chimpanzee (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson Mar 1989

Numerical Competence In A Chimpanzee (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson

Sentience Collection

A chimpanzee (Pan troglodytes), trained to count foods and objects by using Arabic numbers, demonstrated the ability to sum arrays of 0-4 food items placed in 2 of 3 possible sites. To address representational use of numbers, we next baited sites with Arabic numbers as stimuli. In both cases performance was significantly above chance from the first sessions, which suggests that without explicit training in combining arrays, the animal was able to select the correct arithmetic sum for arrays of foods or Arabic numbers under novel test conditions. These findings demonstrate that counting strategies and the representational use of numbers …


Non-Breeder Asymmetry In Florida Scrub Jays, Jonathan P. Balcombe Mar 1989

Non-Breeder Asymmetry In Florida Scrub Jays, Jonathan P. Balcombe

Ethology Collection

The data of Woolfenden and Fitzpatrick (1984) show a statistically significant asymmetry in the sex ratio of non-breeders when one of the breeders is not the non-breeder's parent. 1 propose that the asymmetry is attributable to a combination of two factors acting on non-breeders: the value of inheriting a territory, and incest avoidance. Although natal territories are only occasionally inherited by non-breeders, and then apparently only by males, the rate of inheritance is significantly higher for parent/step-parent breeders (n = 6) than when both breeders are the non-breeder's parents (n = 1). An alternative hypothesis, that step-parents determine the non-breeder …


Investigators In Action Feb 1989

Investigators In Action

Close Up Reports

No abstract provided.


Acceptance Of Simulated Oral Rabies Vaccine Baits By Urban Raccoons, John Hadidian, Suzanne R. Jenkins, David H. Johnston, Peter J. Savarie, Victor F. Nettles, David M. Manski, George M. Baer Jan 1989

Acceptance Of Simulated Oral Rabies Vaccine Baits By Urban Raccoons, John Hadidian, Suzanne R. Jenkins, David H. Johnston, Peter J. Savarie, Victor F. Nettles, David M. Manski, George M. Baer

Veterinary Science and Medicine Collection

In summer 1986, a study was conducted to evaluate raccoon (Procyon lotor) acceptance of oral baits that could be used for rabies vaccination, One thousand wax-coated sponge bait cubes were filled with 5 mg of a seromarker (iophenoxic acid), placed in polyethylene bags, and hand-distributed in an 80 ha area within an urban National Park in Washington, D.C. (USA), After 3 wk, target and nontarget animals were trapped and blood samples collected to evaluate bait uptake. Thirty-three of 52 (63%) raccoons had elevated blood iodine levels indicating they had eaten at least one bait, 13 (25%) were negative, and six …


The Hidden Costs Of Beef, Michael W. Fox, Nancy E. Wiswall Jan 1989

The Hidden Costs Of Beef, Michael W. Fox, Nancy E. Wiswall

eBooks

No abstract provided.


Conspecific Recognition In The Chimpanzee (Pan Troglodytes): Cardiac Responses To Significant Others, Sarah T. Boysen, Gary G. Berntson Jan 1989

Conspecific Recognition In The Chimpanzee (Pan Troglodytes): Cardiac Responses To Significant Others, Sarah T. Boysen, Gary G. Berntson

Sentience Collection

The ability of a chimpanzee (Pan troglodytes) to recognize photographs of conspecifics was evaluated with heart-rate measures. Heart rate was recorded before, during, and after viewing photographs of an aggressive chimpanzee, a friendly companion animal, and an unfamiliar chimpanzee. The subject displayed a differential pattern of heart-rate response to the stimulus animals, without prior experience with the photographs. Responses to the aggressive animal were acceleratory, which suggests a defensive response. Respiratory sinus arrhythmia suggested that this response was associated with sympathetic activation. In contrast, responses to the familiar animal were minimal, whereas cardiac deceleration was observed in response to the …