White Leghorn (WL) breed is homozygous for an allele on the α2C-AR gene while the Red Junglefowl (RJF) is mostly heterozygous for that. The gene is also hypermethylated in WL. The gene codes for the α2C -adrenergic receptor, which plays various roles including regulation of neurotransmitter release from adrenergic neurons in the central nervous system and sympathetic nerves The aim of this study was to investigate the effects of the variation of α2C-AR gene on the chickens’ behaviour. Various behavioural tests mostly associated with fear and stress was conducted in progeny of an F9 generation of the advanced intercross line (AIL) between RJF and WL, selected for homozygosity of the alternative alleles on the α2C-AR gene. In the emergence test, the stress effect on both poking and total exit latency was significantly higher in WL genotype females in comparison to RJF genotype females (effect on head poking time: WL -70.62 ± 18.603 versus RJF 15.63 ± 29.069; effect on total exit time WL -72.14 ± 20.582 RJF 5.64 ± 30.140). In the aerial predator test RJF genotype birds showed significantly more agitated behaviours after the predator exposure in comparison to WL genotype birds (RJF 27.65 ± 0.700 versus WL 25.09 ± 0.915) Although we found differences in behaviour of individuals with WL genotype, more research is needed to find out how the variation on the ADRA2C gene has played a role in domestication of layer chicken.

Commercial equipment used by the turkey industry at hatch sterilizes the germinal tissue of the claw with microwave energy and the beak tissue with infrared energy. This effectively claw and beak trims the birds. To test this technique on chickens, one-half of two strains of 1,200 Leghorn chicks were each subjected to the claw reduction (RC) technique at hatch, while one-half retained intact claws (IC). The beaks of one-third of these treatments were reduced at hatch using the infrared technique (1-day), one-third were precision trimmed at 7 d of age (7-day), and one-third were not trimmed (IB). Body weight, weight gain, feed intake, feed conversion, mortality, and fearfulness were measured. Rearing followed standard commercial feeding and husbandry procedures. During the preliminary experiment, heterophil to lymphocyte ratios did not consistently differ significantly between treatments. The RC birds had significantly lower body weight, except from 3 to 6 wk and had significantly lower feed consumption from 8 to 18 wk. The 1-day beak trimmed (BT) birds had significantly lower body weight from 3 to 14 wk and ate less total feed by 4 wk. Subjective evaluation showed that the RC birds exhibited less fearfulness during the growing period than the IC birds. Throughout lay, the body weight of RC and BT birds was significantly affected. Feed consumption was not lessened for RC birds, but was for BT birds throughout lay. Egg production, egg quality, and mortality were not affected by either treatment. / Master of Science

Observations of consistency in behavioural responses in animals suggest that animals have personality, a term previously mainly used when describing humans. The expression of differences in personality, similar to expression of variation in behaviour, is in principle dependent on genetic background, environmental factors and experiences. Therefore, by estimating heritability one can determine to which extent the genes affect the phenotypic expression of behaviour. This has rarely been done for variation in animal personality. The aim of the present study was therefore to estimate the consistency and heritability of personality traits in red junglefowl chicks (Gallus gallus). Consistency of behaviours within individuals (n=100) was determined from their responses to repeated novel arena tests, novel object tests and tonic immobility tests. A comparison between the offspring and the parent generation, both with known personalities, through a linear regression enabled me to estimate heritability of behavioural responses in these birds. The results showed a consistency in exploratory, boldness, risk-taking behaviour, and fearfulness in red junglefowl. Additionally, heritability estimates for exploratory, risk-taking and foraging behaviours were found. Taken together, this shows that in the red junglefowl, similar to in other species, personality have both a heritable and an environmental component. An important aim in biology education is the scientific approach, where hypothesis, experimentation, processing results and discussing the results are in focus. Learning and gaining knowledge through the process is a key factor, and will hopefully increase the interest in science among Swedish pupils.

Tests of emotional reactivity have been used in a broad range of basic and applied research and have been primarily concerned with how rearing conditions, particularly environmental enrichment, can affect reactivity. However, assessment of how emotional reactivity can be altered during testing procedures and how it affects behaviors such as exploration is relatively uncommon. The present study assessed the explorative responses of Northern bobwhite quail (Colinus virginianus) neonates under conditions of either elevated or attenuated emotional reactivity during a maze task. Measures of emotional reactivity were compared with measures of exploration to determine their relationship with one another. Chicks that were highly emotionally reactive were generally less willing to explore during the maze task than chicks that were less emotionally reactive. Results indicate that levels of emotional reactivity and approach/avoidance motivation play a role in the speed and amount of exploration that is likely to occur in novel environments.

<p>The aim of this thesis was to study chickens of an F7 intercross between red junglefowl and White Leghorn layers in five behavioural tests to see if there were any correlations between traits in the intercross. 80 animals were used (40 males, 40 females); they were tested in a tonic immobility test, an open field, a fear of human test, an aggression test and lastly a sociality test. The results indicate a pair of correlations between the different variables; chickens with long tonic immobility duration were less aggressive, and chickens with a high fear of humans were more social towards other chickens, which could suggest a correlation between fear and social behaviour/aggression. The results from this study also support previous studies showing that one QTL controls chickens’ behaviour in the tonic immobility test based on the correlations found between the variables in the tonic immobility test. Differences between the genders were found in variables that correlated with each other; this could lead to a speculative suggestion that those behaviours are affected by genes on the X-chromosome. There was also a significant relationship between the weight of the male chickens and their behaviour in the open field test and in the fear of human test, in which the heavier males were less fearful than the lighter ones.</p>

The aim of this thesis was to study chickens of an F7 intercross between red junglefowl and White Leghorn layers in five behavioural tests to see if there were any correlations between traits in the intercross. 80 animals were used (40 males, 40 females); they were tested in a tonic immobility test, an open field, a fear of human test, an aggression test and lastly a sociality test. The results indicate a pair of correlations between the different variables; chickens with long tonic immobility duration were less aggressive, and chickens with a high fear of humans were more social towards other chickens, which could suggest a correlation between fear and social behaviour/aggression. The results from this study also support previous studies showing that one QTL controls chickens’ behaviour in the tonic immobility test based on the correlations found between the variables in the tonic immobility test. Differences between the genders were found in variables that correlated with each other; this could lead to a speculative suggestion that those behaviours are affected by genes on the X-chromosome. There was also a significant relationship between the weight of the male chickens and their behaviour in the open field test and in the fear of human test, in which the heavier males were less fearful than the lighter ones.

<p>The fear response of two different captive populations of red jungle fowl (rjf, Gallus gallus) was measured in three different tests, a ground predator test, an aerial predator test and a tonic immobility test. The two populations originated from Copenhagen zoo (Cop) and Götala research station (Got) but had been kept together for four generations. Earlier generations had a confirmed difference in fearfulness where the Cop birds exhibited a higher degree of fear response than Got birds (Håkansson and Jensen, 2005; Håkansson et al., 2007). The most and least fearful birds of each sex and population were identified and used in a gene expression study. The midbrain regions from the candidate birds were collected and RNA was isolated from each brain. The RNA was then reversed transcribed to cDNA which was used in a cDNA microarray experiment. 13 significantly differentially expressed genes were found between the fearful and non-fearful females. Among others were the neuroprotein Axin1, two potential DNA/RNA regulating proteins and an unknown transcript in the Quantitative Trait Locus 1(QTL 1), a well studied QTL on chromosome one with substantial effect on both behaviour and morphology during domestication (Schütz et al., 2002). This thesis succeeds in finding a difference in gene expression between fearful and non fearful female rjf but not between males. It fails in identifying gene expression differences between the two populations. Finally, the found differentiated genes suggest a potential molecular mechanism controlling the fear response in fowl.</p>

The fear response of two different captive populations of red jungle fowl (rjf, Gallus gallus) was measured in three different tests, a ground predator test, an aerial predator test and a tonic immobility test. The two populations originated from Copenhagen zoo (Cop) and Götala research station (Got) but had been kept together for four generations. Earlier generations had a confirmed difference in fearfulness where the Cop birds exhibited a higher degree of fear response than Got birds (Håkansson and Jensen, 2005; Håkansson et al., 2007). The most and least fearful birds of each sex and population were identified and used in a gene expression study. The midbrain regions from the candidate birds were collected and RNA was isolated from each brain. The RNA was then reversed transcribed to cDNA which was used in a cDNA microarray experiment. 13 significantly differentially expressed genes were found between the fearful and non-fearful females. Among others were the neuroprotein Axin1, two potential DNA/RNA regulating proteins and an unknown transcript in the Quantitative Trait Locus 1(QTL 1), a well studied QTL on chromosome one with substantial effect on both behaviour and morphology during domestication (Schütz et al., 2002). This thesis succeeds in finding a difference in gene expression between fearful and non fearful female rjf but not between males. It fails in identifying gene expression differences between the two populations. Finally, the found differentiated genes suggest a potential molecular mechanism controlling the fear response in fowl.

Neophobia, the fear of novelty, is a behavioral trait found across a number of animal species, including humans. Neophobic individuals perceive novel environments and stimuli to have aversive properties, and exhibit fearful behaviors when presented with non-familiar situations. The present study examined how early life exposure to aversive novel stimuli could reduce neophobia in bobwhite quail chicks. Experiment 1 exposed chicks to a novel auditory tone previously shown to be aversive to naïve chicks (Suarez, 2012) for 24 hours immediately after hatching, then subsequently tested them in the presence of the tone within a novel maze task. Postnatally exposed chicks demonstrated decreased fearfulness compared to naïve chicks, and behaved more similarly to chicks tested in the presence of a known attractive auditory stimulus (a bobwhite maternal assembly call vocalization). Experiment 2 exposed chicks to the novel auditory tone for 24 hours prenatally, then subsequently tested them within a novel maze task. Prenatally exposed chicks showed decreased fearfulness to a similar degree as those postnatally exposed, revealing that both prenatal and postnatal exposure methods are capable of decreasing fear of auditory stimuli. Experiment 3 exposed chicks to a novel visual stimulus for 24 hours postnatally, then subsequently tested them within a novel emergence box / T-maze apparatus. Chicks exposed to the visual stimulus showed decreased fearfulness compared to naïve chicks, thereby demonstrating the utility of this method across sense modalities. Experiment 4 assessed whether early postnatal exposure to one novel stimulus could generalize and serve to decrease fear of novelty when chicks were tested in the presence of markedly different stimuli. By combining the methods of Experiments 1 and 3, this experiment revealed that chicks exposed to one type of stimulus (auditory or visual) demonstrated decreased fear when subsequently tested in the presence of the opposite type of novel stimulus. These results suggest that experience with novel stimuli can moderate the extent to which neophobia will develop during early development.