The pecking of birds has been classically considered a fixed action pattern that is little modified by varying internal and external circumstances. i\lthough recent research has documented several instances of variability, the stereotypy of pecking by pigeons continues to be stressed. The present study illustrates the adaptability of the response employing an accelerometric/videographic techniq...

................................................................................................................................ 37 CHAPTER 1: General Introduction ......................................................................................... 44 TYPES OF BIRD-TO-BIRD PECKING .................................................................................. 47 HOUSING SYSTEMS ...........

intramascular (im) administration of apomorphine (a mixed d1/d2 dopamine receptors agonist 0.2-1.6 mg/kg) induced pecking, a stereotype behavior in pigeons in a dose- dependent manner. in this study the effect of lithium (li+, 240 mg/kg, im) and ami-193 (a new 5-ht2 antagonist, 0.003 mg/pigeon) on apomorphine-induced peking (aip) were investigated. this study showed that li+ and ami-193 did not...

The aim of this empirical study is to explore the trade-off model and pecking order model of capital structure. The investigation is performed using panel data procedures for a sample of 76 firms listed in Tehran Stock Exchange during 2007-2010.The study employs OLS regression model in examining the capital structure of firms in Iran. The study employs variables reflecting differing theoretical...

Feather pecking in domestic fowl is a behavioral abnormality that consists of mild or injurious pecking at feathers of conspecifics. Previously, it was shown that chicks from a high feather-pecking (HFP) and low feather-pecking (LFP) line of laying hens already differ in their propensity to feather peck at 14 and 28 days of age. As a first step in investigating a possible relationship between t...

The objective of the current study was to estimate heritabilities (h2) of feather pecking and openfield response of laying hens at two different ages. An F2 cross, originating from a high and a low feather pecking line of laying hens, was used for the experiment. Each of the 630 birds of the F2 cross was subjected to an openfield test (individual, 10 min) at 5 and 29 wk of age and to a social f...

Divergent choose-absence retention functions typically found in pigeons following presence/absence-sample matching have been attributed to the development of a single-code/default coding strategy. However, such effects may result from adventitious differential responding to the samples. In Experiment 1, retention functions were divergent only when differential sample responding could serve as t...

Feather pecking is a behavioural disorder in laying hens which consists of pecking the feathers of conspecifics, causing feather damage or even injuries to the skin. Its development can be explained by redirection of foraging behaviour. While the occurrence of feather pecking strongly depends on the kind of housing condition, it is also known that there are strain differences in the tendency to...

A fully automated procedure, involving computer-controlled stimulus presentation and computer-recorded response measurement, was used for the first time to study imitation in non-human animals. After preliminary training to peck and step on a manipulandum, budgerigars were given a discrimination task in which they were rewarded with food for pecking during observation of pecking and for steppin...