Four experiments examined the discrimination of directional object motion by pigeons. Four pigeons were tested in a go/no-go procedure with video stimuli of pigeons rotating right or left around their central y-axis. This directional discrimination was learned in 7 to 12 sessions and was not affected by changes in object starting orientation, but did require the coherent ordering of the videos'...

By using a free-operant instrumental discrimination procedure, it was demonstrated that pigeons find two-dimensional mirror-image visual forms more difficult to distinguish than otherwise similar forms. Variations in orientation of the discriminanda exacerbated the relative confusability of mirror images. No significant difference was found in the pigeons' performance whether the birds were dis...

BACKGROUND Hadjelia truncata is a nematode that causes lesions in the gizzard lining of pigeons, which may even lead to death. The aim of this study was to introduce Alphitobius diaperinus as a new intermediate host for Hadjelia truncata. METHODS H. truncata infection was identified in a pigeon flock in Ahvaz City, Khuzestan Province, Iran by performing fecal examination and autopsy. Adult an...

Recent evidence indicates that pigeons can readily learn visual discriminations based on both absolute and relational stimulus factors. To examine how these two types of control function in their non-dominant auditory modality, we tested four pigeons in a go/no-go sequential auditory discrimination in which both absolute and relational cues were redundantly available. In this task, sequences of...

Resumen Background: An experiment with pigeons was conducted for 46 months in order to test the multiple-exemplar training (MET) hypothesis of symmetry derivation. According to this hypothesis, symmetry is progressively derived after an extensive training of multiple examples of direct and inverse relations among arbitrary stimuli. Method: Four pigeons were given extensive training in direct (e...

Metabolic rate (MR) and various body temperatures were recorded in pigeons Columba livia during gradual lowering of the ambient temperature (Ta) and during cold exposure (-10 degrees C) for an entire circadian cycle. The aim was to study how changes in MR accorded with the observed body temperature displacements and our knowledge of regional cold sensitivity. When Ta was lowered from 28 to -10 ...

A genetically selected line of White Carneau pigeons (WC-2) was studied in an attempt to relate changes in composition and content of aortic glycosaminoglycan (GAG) to increased atherosclerosis susceptibility. The WC-2 pigeons were fed an atherogenic diet for 3 months and, when compared to randomly bred White Carneau (RBWC) controls, they showed similar plasma cholesterol concentrations but sig...

The cues by which homing pigeons are able to return to a home loft after displacement to unfamiliar release sites remain debated. A number of experiments in which migratory birds have been treated with a magnetic pulse have produced a disruption in their orientation, which argues that a ferrimagnetic sense is used for navigation in birds. One previous experiment has also indicated an effect of ...

Using a simultaneaus discrimination procedure it was shown that pigeons were capable of learning to discriminate 100 different black and white visual patterns from a further 625 similar stimuli, where responses to the former were rewarded and responses to the latter were not rewarded. Tests in which novel stimuli replaced either the rewarded or nonrewarded stimuli showed that the pigeons had no...

Objective- Because of the several differences between avian and mammalian physiology and anatomy, avian anesthesia requires to be more attentive. The aim of this study was to determine a safe injectable anesthetic agent that had more compatibility with the avian features. Design- Experimental study Animals- Twelve male pigeons...