Influence of stocking density on tonic immobility, lameness, and tibial dyschondroplasia in broilers
Contributor(s):: Sanotra, G. S., Lawson, L. G., Vestergaard, K. S.
This study assessed the effect of stocking density on the development of fear reaction (tonic immobility), lameness (gait), and tibial dyschondroplasia in broiler chicks of mixed sex. During 3 experiments, the study used 49 500 broiler chicks (Ross 208). Of these, 432 focal chicks were randomly...
Comparison of the tonic immobility duration, heterophil to lymphocyte ratio, and fluctuating asymmetry of chicks reared with or without a broody hen, and of broody and non-broody hens
Contributor(s):: Campo, J. L., Davila, S. G., Gil, M. G.
The purposes of this study were to determine whether rearing with a broody hen influenced duration of tonic immobility, heterophil to lymphocyte ratio, and relative fluctuating asymmetry of chicks and to analyze the differences between broody and non-broody hens in fear and stress indicators. A...
Disrupting motivational sequences in chicks: are there affective consequences?
Contributor(s):: Seehuus, B., Mendl, M., Keeling, L. J., Blokhuis, H.
The influence of access to aerial perches on fearfulness, social behaviour and production parameters in free-range laying hens
Contributor(s):: Donaldson, C. J., O'Connell, N. E.
Day-old chicks categorised on latency to peck, exhibit a stable fear pattern until 15 days of age
Contributor(s):: Salvatierra, N. A., Arce, A.
Day-old chicks (n=24) of both sexes were individually categorized on the latency to peck pebbles and termed as high latency (HL), moderate latency (ML) or low latency (LL). Anxiolytic doses of diazepam diminished the latency only in the HL category, suggesting that it is the most anxious...
Domestication effects on foraging strategy, social behaviour and different fear responses: a comparison between the red junglefowl ( Gallus gallus ) and a modern layer strain
Contributor(s):: Schutz, K. E., Forkman, B., Jensen, P.
According to the resource allocation theory, behaviours that have high energetic costs should decrease in frequency in breeds that are selected to invest a higher proportion of energy into production traits. We studied differences between red junglefowl, the ancestor of domesticated breeds, and a...
Effects of an acute stressor on fear and on the social reinstatement responses of domestic chicks to cagemates and strangers
Contributor(s):: Marin, R. H., Freytes, P., Guzman, D., Jones, R. B.
Genetic selection for appropriate levels of sociality (motivation to be with conspecifics) could benefit poultry welfare and performance. Runway tests that require chicks to traverse a corridor in order to reach other chicks in a goal box are commonly used to measure this behavioural trait....
Laying hens selected for low mortality: behaviour in tests of fearfulness, anxiety and cognition
Contributor(s):: Nordquist, R. E., Heerkens, J. L. T., Rodenburg, T. B., Boks, S., Ellen, E. D., Staay, F. J. van der
Feather pecking and cannibalism in chickens can lead to injury or to death of the victims, and is thus a serious welfare and economic issue in modern poultry farming. A sib selection scheme has been initiated to genetically select a low mortality line (LML), which shows decreased mortality due to...
Pecking preferences and pre-dispositions in domestic chicks: implications for the development of environmental enrichment devices
Contributor(s):: Jones, R. B., Carmichael, N. L., Rayner, E.
Environmental enrichment is thought likely to benefit fowls and farmers in many ways; these include reduced fearfulness and feather pecking and improved productivity. Enrichment devices would intuitively be more effective if they reliably attracted and sustained appreciable interest but many fail...
The effects of regular visual contact with human beings on fear, stress, antibody and growth responses in broiler chickens
Contributor(s):: Zulkifli, I., Gilbert, J., Liew, P. K., Ginsos, J.
This study investigated the effects of regular visual contact at various ages on tonic immobility (TI) and heterophil/lymphocyte ratio (HLR) reactions to handling and crating, antibody production, growth performance and feed conversion ratios in commercial broiler chicks. Broiler chicks were...
Effects of prior video stimulation on open-field behaviour in domestic chicks
Contributor(s):: Clarke, C. H., Jones, R. B.
Two experiments examined the effects of regular video stimulation on open-field behaviour in domestic chicks tested in the presence (Experiment 1) or absence (Experiment 2) of the familiar video image. In Experiment 1, socially housed chicks were either exposed daily from 2 to 8 days of age to...
Fearful behavior by caged hens of two genetic stocks
Contributor(s):: Craig, J. V., Craig, T. P., Dayton, A. D.
Two White Leghorn strains which had both been selected for increased part-year egg mass but differed significantly from each other in agonistic behaviour, and sire families within each strain, were compared for nervousness scores and for latencies to feed and to return to normal activity after...
The development of fear responses and stereotypes in fowls
Contributor(s):: Duncan, I. J. H.
The open field as a stressor: fear in domestic chicks
Contributor(s):: Jones, R. B.
Young domestic chicks avoid eye-like shapes
A note on fear reaction of three different genetic strains of laying hens to a simulated hawk attack in the hen run of a free-range system
Contributor(s):: Zeltner, E., Hirt, H.
Hens well adapted to free-range systems should react quickly to avoid an attack by a predator but should also be able to return to the hen run soon after to ensure good use of the outside area. To ascertain if some strains cope better with a frightening event the fear reaction of three different...
Effect of broody hens on behaviour of chicks
Contributor(s):: Shimmura, T., Kamimura, E., Azuma, T., Kansaku, N., Uetake, K., Tanaka, T.
The objective of the present study was to examine the details of dynamic changes of behaviour of brooded and non-brooded chicks at an early age, the effects of broody hens on the behavioural development and fearfulness of chicks and the correlation between maternal care and fearfulness of chicks,...
Effect of simulated long transport on behavioural characteristics in two strains of laying hen chicks
Contributor(s):: Valros, A., Vuorenmaa, R., Janczak, A. M.
Newly hatched chicks are routinely subjected to varying durations of transport shortly after hatching. Because little is known about the effects of this putative stressor on behavioural development, the present experiment tested for the effects of a simulated long transport-like treatment during...
Effects of visual stimuli and noise on fear levels in laying hens
Contributor(s):: Scott, G. B., Moran, P.
Conveyors have been proposed to improve bird welfare during handling procedures, but visual perception of speed may play an important role if birds find the movement frightening. To study this, stationary birds were subjected to moving stimuli of 0.33, 0.67 and 1.00 m/s by being placed between...
Fear and stress reactions, and the performance of commercial broiler chickens subjected to regular pleasant and unpleasant contacts with human being
Contributor(s):: Zulkifli, I., Azah, A. S. N.
An experiment was conducted to determine the effects of regular pleasant and unpleasant contacts with human beings on tonic immobility (TI) response, heterophil to lymphocyte ratio (HLR), body weight, feed conversion ratios (FCR) and mortality in commercial broiler chickens. The following...