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Articles 1 - 9 of 9
Full-Text Articles in Animal Sciences
Evaluation Of Animal Welfare By The Self-Expression Of An Anxiety State, M. P. Carey, J. P. Fry
Evaluation Of Animal Welfare By The Self-Expression Of An Anxiety State, M. P. Carey, J. P. Fry
Assessment of Animal Welfare Collection
Although mental well-being has long been accepted as an important aspect of animal welfare, the subjective feelings of farm or laboratory animals are regarded as lying beyond the scope of scientific enquiry. We now report that pharmacological conditioning of pigs with a drug, pentylenetetrazole, known to induce anxiety in man, permits investigation of the presence or absence of this psychological state during exposure to a variety of environmental stimuli encountered during normal husbandry. Such pharmacological conditioning therefore provides a valuable means to assess and improve elements of animal welfare and should be applicable to other species that show operant behaviour.
Conflict And Cooperation: Sociobiological Principles And The Behaviour Of Pigs, David Fraser, D. L. Kramer, E. A. Pajor, D. M. Weary
Conflict And Cooperation: Sociobiological Principles And The Behaviour Of Pigs, David Fraser, D. L. Kramer, E. A. Pajor, D. M. Weary
Sociobiology Collection
The pig provides many examples of how principles of behavioural ecology and sociobiology can lead to insights into farm animal behaviour. According to parent-offspring conflict theory, parents should tend to give a level of parental investment somewhat below that solicited by the young. When closely confined during lactation, sows can do little to limit the amount of contact with the piglets, and the young stimulate a prolonged, high level of lactation. Certain alternative housing systems allow the sow to limit the stimulation she receives, and the resulting reduction in lactation can actually be advantageous to both parties. Communal care of …
Mirror Use By African Grey Parrots (Psittacus Erithacus), Irene M. Pepperberg, Sean E. Garcia, Eric C. Jackson, Sharon Marconi
Mirror Use By African Grey Parrots (Psittacus Erithacus), Irene M. Pepperberg, Sean E. Garcia, Eric C. Jackson, Sharon Marconi
Sentience Collection
No abstract provided.
Indicating Acts During Counting By A Chimpanzee (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson, Traci A. Shreyer, Michelle B. Hannan
Indicating Acts During Counting By A Chimpanzee (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson, Traci A. Shreyer, Michelle B. Hannan
Sentience Collection
A chimpanzee (Pan troglodytes) experienced in counting arrays of 0-7 items and trained for comprehension of number symbols, spontaneously displayed a variety of indicating acts (e.g., pointing, touching, and rearranging items) during counting. Twenty-five sessions were videotaped, and all trials were evaluated for the relations among number of items presented, number of indicating acts displayed, and the Arabic number selected to represent the array. Significant correlations included the relations between number of items and the cardinal number selected by the animal, between the number of items and indicating acts displayed by the chimpanzee, and between the number of indicating acts …
Calling By Domestic Piglets: Reliable Signals Of Need?, Daniel M. Weary, David Fraser
Calling By Domestic Piglets: Reliable Signals Of Need?, Daniel M. Weary, David Fraser
Communication Skills Collection
Two manipulations were performed on domestic piglets to determine whether differences in calling during periods of separation from the mother can indicate differences in need. In both cases, the aim was to manipulate the piglet's need for the sow's attention. In the first manipulation a 'thriving' piglet (i.e. the piglet with the heaviest weight and most rapid weight gain) and a 'non-thriving' one (lightest and slowest weight gain) were selected from each of 15 litters. The two piglets were removed from the sow and litter and recorded for 13 min in separate isolated enclosures. For the second manipulation, two piglets …
Responses To Quantity: Perceptual Versus Cognitive Mechanisms In Chimpanzees (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson
Responses To Quantity: Perceptual Versus Cognitive Mechanisms In Chimpanzees (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson
Sentience Collection
Two chimpanzees were trained to select among 2 different amounts of candy (1-6 items). The task was designed so that selection of either array by the active (selector) chimpanzee resulted in that array being given to the passive (observer) animal, with the remaining (nonselected) array going to the selector. Neither animal was able to select consistently the smaller array, which would reap the larger reward. Rather, both animals preferentially selected the larger array, thereby receiving the smaller number of reinforcers. When Arabic numerals were substituted for the food arrays, however, the selector animal evidenced more optimal performance, immediately selecting the …
Comprehension Of Cause-Effect Relations In A Tool-Using Task By Chimpanzees (Pan Troglodytes), Luca Limongelli, Sarah T. Boysen, Elisabetta Visalberghi
Comprehension Of Cause-Effect Relations In A Tool-Using Task By Chimpanzees (Pan Troglodytes), Luca Limongelli, Sarah T. Boysen, Elisabetta Visalberghi
Sentience Collection
Five chimpanzees (Pan troglodytes) were tested to assess their understanding of causality in a tool task. The task consisted of a transparent tube with a trap-hole drilled in its middle. A reward was randomly placed on either side of the hole. Depending on which side the chimpanzee inserted the stick into, the candy was either pushed out of the tube or into the trap. In Experiment 1, the success rate of 2 chimpanzees rose highly above chance, but that of the other subjects did not. Results show that the 2 successful chimpanzees selected the correct side for insertion beforehand. Experiment …