Interactions between Behaviour and Genetics in Wild and Domestic Bird Populations

Personality traits can be favoured by both natural and artificial selection, if they result in increased fitness or productivity, and therefore play an important role in both wild and domestic populations. Here, we review how personality traits affect and are affected by natural and artificial selection by focusing on studies from both wild and domestic bird populations. Further, we will also explore how artificial selection affects personality and fitness traits in a domestic population. We will use the great tit (Parus major) and the laying hen (Gallus gallus domesticus) as our model species. When comparing the studies on behaviour genetics in great tits and laying hens, it is fascinating to see that two fields of study that seem quite far apart have so much in common

Radio en kleurige overalls helpen tegen verenpikken

Wageningen University heeft samen met de Universiteit Utrecht en de Rijksuniversiteit Groningen manieren gevonden om verenpikken bij leghennen tegen te gaan. Dat biedt perspectief bij het verbod op snavelkappen dat in 2018 van kracht wordt

Sociale scharrelaars of schadelijke schurken?

In dit essay betogen de auteursj dat de combinatie van een verbeterde opfok en houderij en een nieuwe sociale fokkerijstrategie veelbelovend is om sociaal gedrag, en daarmee dierenwelzijn, te verbeteren

Bacterial contamination of table eggs and the influence of housing systems

With the introduction of alternative housing systems for laying hens in the EU, recent research has focussed on the bacterial contamination of table eggs, e.g. eggshell and egg content contamination. Contamination of eggshells with aerobic bacteria is generally higher for nest eggs from non-cage systems compared to nest eggs from furnished cages or eggs from conventional cages. Studies indicate limited or no systematic differences in eggshell contamination with aerobic bacteria between eggs laid in the nest boxes of furnished cages and eggs laid in conventional cages. The major differences found in experimental studies between cage- and non-cage systems are less pronounced under commercial conditions. The effect of housing system on eggshell contamination with specific groups of bacteria is variable. Limited information is available on the influence of housing system on egg content contamination. Recent research does not indicate large differences in egg content contamination between eggs from cage- and non-cage systems (ignoring outside nest and floor eggs). The microflora of the eggshell is dominated by Gram-positive bacteria, whereas Gram-negative bacteria are best equipped to overcome the antimicrobial defences of the egg content. Much of the research on eggshell and egg content contamination focuses on Salmonella, since infection with Salmonella enteritidis, resulting from the consumption of contaminated eggs or egg products, is still a major health problem. Observed Salmonella prevalence on the eggshell and in the egg content vary, depending on the fact whether investigations were based on randomly sampled table eggs or on eggs from naturally infected hens. The limited information available on other pathogens shows that they are exclusively isolated from the eggshell and not from the internal contents

Zonder gezondheidsproblemen geen amgb's en dus ook geen alternatief nodig

Bij gespeende biggen is onderzocht of Calprona-Pe een alternatief kan zijn voor amgb's. Geeft Calprona- Pe of een amgb in het voer betere technische resultaten, in vergelijking met voer zonder amgb. In dit experiment niet. De voerkosten zijn hoger voor voer met amgb dan voor voer zonder amgb of met Calprona-Pe . Er zijn echter geen verschillen in saldo (opbrengst minus kosten). Op bedrijven zonder gezondheidsproblemen lijkt het toevoegen van amgb's of van een alternatief aan het voer niet nodig

Exenta kruidentinctuur biedt perspectief bij diarree-problemen

Bij gespeende biggen is onderzocht of Exenta kruidentinctuur een alternatief kan zijn voor amgb's. Biggen die Exenta kruidentinctuur door het drinkwater kregen, hadden minder vaak, en ook minder ernstige diarree dan dieren die voer zonder amgb's kregen, gedurende de eerste twee weken na opleg. Dit vertaalt zich echter niet in betere technische resultaten. Maar dat geldt ook voor dieren die voer met amgb's kregen. Exenta kruidentinctuur zou met name voor bedrijven met veel maag/darm- problemen een goede mogelijkheid kunnen bieden om de maagdarmgezondheid te stimuleren

Campylobacter and Salmonella infections on organic broiler farms

Organic poultry production in the Netherlands is developing. Although consumers assume organic products to be safer and healthier, there are aspects of organic animal husbandry, like access to an outdoor run, that can result in increased risks of food safety problems. The aim of this study was to compare housing and management of organic and conventional broiler farms in the Netherlands and to study the occurrence of Salmonella and Campylobacter infections on the former. Large differences were found between the two farming systems with respect to mixed or single farming, manure storage, drinking-water system, ventilation, access to an outdoor run, and pest control. From the 31 organic flocks sampled for Salmonella and Campylobacter in 2003, 13% were positive for Salmonella and 35% for Campylobacter. Results for the summer period are missing due to an outbreak of avian influenza, so the actual number of flocks infected with Campylobacter can be expected to be even higher. Campylobacter appears to be the main risk on organic broiler farms, so that it would be interesting to study specific risk factors of infection with this pathogen on these farms

Stress response, peripheral serotonin and natural antibodies in feather pecking genotypes and phenotypes and their relation with coping style

Feather pecking (FP), a serious welfare and economic issue in the egg production industry, has been related to coping style. Proactive and reactive coping styles differ in, among others, the stress response, serotonergic activity and immune activity. Yet, it is unknown whether genetic lines divergently selected on FP (i.e. FP genotypes) or individuals differing in FP (i.e. FP phenotypes) can be categorized into coping styles. Therefore, we determined peripheral serotonin (5-HT) levels, natural antibody (NAb) titers, behavioral and corticosterone (CORT) responses to manual restraint (MR) in FP genotypes (high FP (HFP), low FP (LFP) and unselected control (CON) line) and FP phenotypes (feather pecker, feather pecker-victim, victim and neutral). We further examined the consistency of and relationships between behavioral and physiological measures. FP genotypes differed in behavioral responses to MR, 5-HT levels and NAb titers, but not in CORT levels after MR. HFP birds had less active responses at adolescent age, but more active responses at adult age compared to LFP and CON birds. The CON line had higher 5-HT levels at adolescent age, while the HFP line had lower 5-HT levels than the other lines at adult age. Overall, the HFP line had lower IgM NAb titers, while the LFP line had lower IgG NAb titers compared to the other lines. FP phenotypes differed in behavioral responses to MR and 5-HT levels, but not in CORT levels after MR or NAb titers. Within the HFP line, feather peckers tended to have less active responses compared to neutrals at adolescent age, while victims had more active responses compared to the other phenotypes at adult age. Feather peckers had higher 5-HT levels than neutrals at adult age. Behavioral and CORT responses to MR were not consistent over time, suggesting that responses to MR might not reflect coping style in this study. Furthermore, proactive behavioral responses were correlated with reactive physiological measures and vice versa. Thus, it was not possible to categorize FP genotypes or FP phenotypes into specific coping styles.</p

Biologische vleeskuikenhouderij

In this research the available knowledge on organic broiler husbandry was combined and possible problems were identified. The research shows that there are opportunities for research on food safety, coccidiosis, 100% organic food, mobile housing, the structure of the outdoor run and the type of bird best suited for organic production

Emotions on the loose: emotional contagion and the role of oxytocin in pigs

We studied emotional contagion, a simple form of empathy, and the role of oxytocin herein in pigs. Two training pigs per pen (n = 16 pens) were subjected to a positive treatment (pairwise access to a large compartment filled with peat, straw and some chocolate raisins) and a negative treatment (social isolation in a small compartment) in a test room using a within-subjects design. Thereafter, two naive pen mates joined the training pigs in the test room, but were not given access to the treatments. This allowed testing for emotional contagion. Subsequently, the naive pigs, serving as their own controls, were given 24 IU of oxytocin or a placebo intranasally 30 min before accompanying the training pigs, which were exposed to either the negative or positive treatment, to the test room. Behavioral differences found between the positive and negative treatments (e.g., play and “tail wagging” vs. standing alert, urinating, defecating and ears backward) show that the treatments induced a positive and negative emotional state in the training pigs, respectively. Changes in behaviors of the training pigs with and without naive pigs present (e.g., in ears backwards) and of the naive pigs with and without training pigs present (e.g., in standing alert) indicated that emotional contagion occurred, especially during the negative treatment. Oxytocin did not seem to affect the behavior of the treated naive pigs, but did affect behaviors (e.g., defecating) of the training pigs which had not received oxytocin. This suggests a role for oxytocin in pig communication, which merits further research