The Effect of Rearing and Adult Environment on HPA Axis Responsivity and Plumage Condition in Laying Hens.

The hypothalamic-pituitary-adrenal (HPA) axis responsivity is influenced by early life experience and also modified by the environment an individual experiences as an adult. Because laying hens are transferred from rearing to laying farms at 16-18 weeks of age, they are well suited to study the interaction effect between early (rearing) and adult (laying) environments on physiology and behaviour. In the European Union, there is a move towards cage-free systems for laying hens, but globally, the majority of layers are kept in conventional or furnished cages.

The effect of fentanyl on immobility after noxious stimulation in isoflurane-anaesthetized pigs: Exploring the role of the serotonergic system.

Objective: To investigate if fentanyl induces immobility through activation of the serotonergic 5HT receptor, by using the 5HT-antagonist robalzotan.

Study Design: A prospective, blinded, randomized, two-group study.

Animals: A group of 12 mixed-breed pigs aged 71-79 days.

Motor effects of fentanyl in isoflurane-anaesthetized pigs and the subsequent effect of ketanserin or naloxone.

Objective: To examine the effect of ketanserin and naloxone on fentanyl-induced motor activity in isoflurane-anaesthetized pigs.

Study Design: Randomized, blinded, prospective two-group study.

Animals: A group of 12 crossbred pigs weighing 22-31 kg.

Mind the ramp: Association between early life ramp use and spatial cognition in laying hen pullets.

Ramps facilitate earlier access to complex environments and increase early life voluntary exercise, which may positively affect the cognitive development of chickens. This study focused on quantifying individual differences in ramp use and its impact on spatial cognition of laying hen pullets. Sixteen identical pens were housed with Lohmann Selected Leghorn (LSL) chicks of which eight chicks from each pen were colour marked from one day of age (DoA) to serve as focal birds.

High and Hyper: Fentanyl Induces Psychomotor Side-Effects in Healthy Pigs.

Analgesic effects of fentanyl have been investigated using behavior. The behavioral effects of fentanyl and possible serotonergic influence are largely unknown. We therefore investigated behavioral effects of fentanyl, with or without the serotonin antagonist ketanserin, in pigs.

The Effects of Social vs. Individual Housing of Zebrafish on Whole-Body Cortisol and Behavior in Two Tests of Anxiety.

Two of the most used models of anxiety in zebrafish research, the novel tank-diving test (NTDT) and the black-white preference test (BWPT), are modifications of assays used in rodent research (open field test and light/dark test). There has been a thorough validation of these tests in rodents, but a similar level of knowledge is still missing in zebrafish. Adult zebrafish naturally live in shoals with conspecifics, and group housing is therefore assumed to be the optimal housing condition for zebrafish, as it allows for shoaling behavior.

The Evidence for a Causal Link Between Disease and Damaging Behavior in Pigs.

Damaging behaviors (DB) such as tail and ear biting are prevalent in pig production and reduce welfare and performance. Anecdotal reports suggest that health challenges increase the risk of tail-biting. The prevalence of tail damage and health problems show high correlations across batches within and between farms.

Dynamics of Salivary Adenosine Deaminase, Haptoglobin, and Cortisol in Lipopolysaccharide-Challenged Growing Pigs.

Infectious and inflammatory conditions are common especially in growing pigs. Lipopolysaccharide (LPS) is an important antigenic structure of Gram-negative bacteria and can be used to induce inflammation experimentally. As pigs are usually group-housed in commercial conditions, it is difficult to detect sick individuals, particularly at an early stage of illness.

The Effect of LPS and Ketoprofen on Cytokines, Brain Monoamines, and Social Behavior in Group-Housed Pigs.

Poor health is a risk factor for damaging behaviors, but the mechanisms behind this link are unknown. Injection of pigs with lipopolysaccharide (LPS) can be used to model aspects of poor health. Recent studies have shown that LPS-injected pigs perform more tail- and ear-directed behavior compared to saline-injected pigs and suggest that pro-inflammatory cytokines may play a role in these behaviors.

Inhibition and facilitation of nociceptively evoked muscular activity by fentanyl or dexmedetomidine in isoflurane-anaesthetized pigs.

Objective: To investigate motor and cardiovascular responses to dexmedetomidine or fentanyl in isoflurane-anaesthetized pigs.

Study Design: Experimental, balanced, block randomized, two-group design.

Animals: A group of 16 crossbred pigs, 55 ± 8 days (mean ± standard deviation) old.

A Proposed Role for Pro-Inflammatory Cytokines in Damaging Behavior in Pigs.

Sickness can change our mood for the worse, leaving us sad, lethargic, grumpy and less socially inclined. This mood change is part of a set of behavioral symptoms called sickness behavior and has features in common with core symptoms of depression. Therefore, the physiological changes induced by immune activation, for example following infection, are in the spotlight for explaining mechanisms behind mental health challenges such as depression.

Sick and grumpy: Changes in social behaviour after a controlled immune stimulation in group-housed gilts.

Poor health is associated with an increased risk of tail biting outbreaks in pigs. We propose that this is because illness changes social dynamics either by changing the behaviour of the sick pig towards its penmates, the behaviour of the healthy penmates towards the sick pig, or both. We tested the effect of immune stimulation (lipopolysaccharide (LPS) injection: O111:B4; 1.

The effect of lipopolysaccharide (LPS) on inflammatory markers in blood and brain and on behavior in individually-housed pigs.

Most of us have experienced deterioration of mood while ill. In humans, immune activation is associated with lethargy and social withdrawal, irritability and aggression; changes in social motivation could, in theory, lead to less functional interactions. This might also be the case for animals housed in close confinement.

Problem behaviors in adult laying hens - identifying risk factors during rearing and egg production.

Feather pecking, toe pecking, cannibalism, smothering, social clumping, hens laying eggs outside the nest boxes, and reduced feather quality are examples of problem behaviors and consequences reported by egg producers. The aim of this study was to identify rearing- and production-related risk factors associated with producer-reported problem behaviors in Norwegian layer flocks. Questionnaires were distributed to 410 egg producers nationwide, and 120 producers responded to the survey (response rate 29%).

DNA methylation profiles in red blood cells of adult hens correlate with their rearing conditions.

Stressful conditions are common in the environment where production animals are reared. Stress in animals is usually determined by the levels of stress-related hormones. A big challenge, however, is in determining the history of exposure of an organism to stress, because the release of stress hormones can show an acute (and recent) but not a sustained exposure to stress.

Does Early Environmental Complexity Influence Tyrosine Hydroxylase in the Chicken Hippocampus and "Prefrontal" Caudolateral Nidopallium?

In adult chickens, the housing system influences hippocampal morphology and neurochemistry. However, no work has been done investigating the effects of the early life environment on chicken brain development. In the present study, we reared 67 commercial laying hens (Gallus gallus domesticus) in two environments that differed in the degree of complexity (aviary or cage system).

Early Life in a Barren Environment Adversely Affects Spatial Cognition in Laying Hens (Gallus gallus domesticus).

Spatial cognition in vertebrates is adversely affected by a lack of environmental complexity during early life. However, to our knowledge, no previous studies have tested the effect of early exposure to varying degrees of environmental complexity on specific components of spatial cognition in chickens. There are two main rearing systems for laying hens in the EU: aviaries and cages.

Anticipatory and foraging behaviors in response to palatable food reward in chickens: effects of dopamine D2 receptor blockade and domestication.

Behaviors associated with anticipation and search for palatable food may provide information about dopaminergic reward processes and positive motivational affect in animals. The overall aim was to investigate the involvement of dopamine signaling in the regulation of cue-induced anticipation and search for palatable food reward in chicken, and whether domestication has affected expression of reward-related behaviors. The specific aims were to describe effects of mealworms (palatable food for hens) and haloperidol (a dopamine D2 antagonist) on foraging behaviors and cue-induced anticipatory behaviors in Red Junglefowl (RJF; the wild ancestor of modern laying hens) and a white layer hybrid (LSL).

Ectoparasitic sea lice (Lepeophtheirus salmonis) affect behavior and brain serotonergic activity in Atlantic salmon (Salmo salar L.): Perspectives on animal welfare.

Scientific research and public debate on the welfare of animals in human custody is increasing at present. Fish are in this context mentioned with particular attention to the high numbers of individuals reared in aquaculture. Research on fish has also contributed to the understanding of individual variation in the ability to cope with stress and disease.

Behavioural effects of the commonly used fish anaesthetic tricaine methanesulfonate (MS-222) on zebrafish (Danio rerio) and its relevance for the acetic acid pain test.

The pros and cons of using anaesthesia when handling fish in connection with experiments are debated. A widely adopted practice is to wait thirty minutes after anaesthesia before behavioural observations are initiated, but information about immediate effects of a treatment is then lost. This is pertinent for responses to acute stressors, such as acid injection in the acetic acid pain test.

Factors affecting mechanical (nociceptive) thresholds in piglets.

Objective: To evaluate the stability and repeatability of measures of mechanical (nociceptive) thresholds in piglets and to examine potentially confounding factors when using a hand held algometer.

Study Design: Descriptive, prospective cohort.

Animals: Forty-four piglets from four litters, weighing 4.

Effects of haloperidol, a dopamine D2-like receptor antagonist, on reward-related behaviors in laying hens.

In order to investigate the involvement of dopaminergic transmission in the regulation of reward-related behaviors in laying hens, the effects of systemic injections of dopamine D2-like receptor antagonist haloperidol (0.3, 0.5, 1.

Pharmacokinetics of morphine after intramuscular injection in common goldfish Carassius auratus and Atlantic salmon Salmo salar.

Teleost fish have a nociceptive system and likely perceive pain. This warrants the development of analgesic protocols both for experimental surgery and for various husbandry procedures. Morphine is the standard analgesic against which the efficacy of other analgesics is assessed, and is the analgesic that has been most used in fish.

Trace classical conditioning in rainbow trout (Oncorhynchus mykiss): what do they learn?

There are two main memory systems: declarative and procedural memory. Knowledge of these two systems in fish is scarce, and controlled laboratory studies are needed. Trace classical conditioning is an experimentally tractable model of declarative memory.