Environmental enrichment reduces behavioural alterations induced by chronic stress in Japanese quail

Live yellow mealworm (Tenebrio molitor) larvae: a promising nutritional enrichment for laying quails

The study aimed to evaluate the effect of supplementing live Tenebrio molitor (TM) larvae to laying quails (Coturnix japonica) as nutritional enrichment. Live performances, apparent digestibility of nutrients (including that of sole live TM larvae), egg physicochemical quality, sensory traits, and storage stability were considered in this experiment. Sixty laying quails were divided into 2 dietary groups (6 replicated cages/group; 5 quails/cage): a Control group received a basal diet for laying quails and a TM10 group was fed with the Control diet supplemented with live TM larvae (10% of the expected daily feed intake). For the digestibility trial, 30 laying quails were divided into 3 dietary groups: the first 2 groups were fed with the Control and TM10 diets, while the third group received ad libitum live TM larvae (TM100) as a complete replacement for the Control diet. Overall, no mortality was recorded during the trials. Quails fed TM showed a remarkable capability of digesting dietary chitin (P < 0.0001). TM100 quails showed the lowest digestibility for dry matter, crude protein, and energy, but that of ether extract was the highest (P < 0.001). The presence of live TM larvae stimulated quails' feed intake (P < 0.0001), but did not affect performance traits. Similarly, overall physicochemical quality attributes and storage stability were comparable in Control and TM10 eggs. The sensory features of quail eggs differed in TM10 vs. Control groups: TM10 eggs had the lowest overall flavor (P < 0.01), sulfur (P < 0.05) and greasy-oily (P < 0.01) intensities. Therefore, a 10% TM dietary supplementation is effective in stimulating feeding activity of quails, but it did not provide any productive improvement compared to a standard diet. Further studies should assess the possible beneficial effect of live TM supplementation on quail's gut health. The digestibility trial with the sole live TM larvae allowed to assess the specific nutritional value of this emerging feedstuff which is of utmost importance for future feed formulations.

Welfare of ducks, geese and quail on farm

This Scientific Opinion concerns the welfare of Domestic ducks (Anas platyrhynchos domesticus), Muscovy ducks (Cairina moschata domesticus) and their hybrids (Mule ducks), Domestic geese (Anser anser f. domesticus) and Japanese quail (Coturnix japonica) in relation to the rearing of breeders, birds for meat, Muscovy and Mule ducks and Domestic geese for foie gras and layer Japanese quail for egg production. The most common husbandry systems (HSs) in the European Union are described for each animal species and category. The following welfare consequences are described and assessed for each species: restriction of movement, injuries (bone lesions including fractures and dislocations, soft tissue lesions and integument damage and locomotory disorders including lameness), group stress, inability to perform comfort behaviour, inability to perform exploratory or foraging behaviour and inability to express maternal behaviour (related to prelaying and nesting behaviours). Animal-based measures relevant for the assessment of these welfare consequences were identified and described. The relevant hazards leading to the welfare consequences in the different HSs were identified. Specific factors such as space allowance (including minimum enclosure area and height) per bird, group size, floor quality, characteristics of nesting facilities and enrichment provided (including access to water to fulfil biological needs) were assessed in relation to the welfare consequences and, recommendations on how to prevent the welfare consequences were provided in a quantitative or qualitative way.

Short photoperiod modulates behavior, cognition and hippocampal neurogenesis in male Japanese quail

The mechanisms underlying the photoperiodic control of reproduction in mammals and birds have been recently clarified. In contrast, the potential impact of photoperiod on more complex, integrative processes, such as cognitive behaviors, remains poorly characterized. Here, we investigated the impact of contrasted long and short photoperiods (LP, 16 h light/day and SP, 8 h light/day, respectively) on learning, spatial orientation abilities, and emotional reactivity in male Japanese quail. In addition, we quantified cell proliferation and young cell maturation/migration within the hippocampus, a brain region involved in spatial orientation. Our study reveals that, in male quail, SP increases emotional responses and spatial orientation abilities, compared to LP. Behaviorally, SP birds were found to be more fearful than LP birds, exhibiting more freezing in the open field and taking longer to exit the dark compartment in the emergence test. Furthermore, SP birds were significantly less aggressive than LP birds in a mirror test. Cognitively, SP birds were slower to habituate and learn a spatial orientation task compared to LP birds. However, during a recall test, SP birds performed better than LP birds. From a neuroanatomical standpoint, SP birds had a significantly lower density of young neurons, and also tended to have a lower density of mature neurons within the hippocampus, compared to LP birds. In conclusion, our data reveal that, beyond breeding control, photoperiod also exerts a profound influence on behavior, cognition, and brain plasticity, which comprise the seasonal program of this species.

Environmental Enrichment as Part of the Improvement of the Welfare of Japanese Quails

Simple Summary

Nowadays, keeping animals in cage systems is controversial. Regulations and increased consumer awareness are causing cage systems to lose ground in many countries. In the case of Japanese quails bred for both egg and meat production, their maintenance in a non-cage system is very difficult and uneconomical; therefore, they are kept in cages, and, unlike egg-laying hens, the regulations only regulate the basic parameters, such as cage size and access to food and water. Taking this into account, studies have been conducted that indicate that keeping quails in enriched cages improves the birds’ welfare.

Abstract

The aim of this study was to evaluate the indicators of the behavioural and physiological welfare of Japanese quails (Coturnix japonica) as possible responses to the enrichment of the birds’ habitat. The study sample consisted of 280 Japanese quails (224 ♀ and 56 ♂, respectively). Birds of 5 weeks of age were randomly divided into seven equally sized groups and then divided into replication subgroups (four per group, 10 birds in each replication). Birds were maintained in 0.5 m² cages with unrestricted access to water and food. The experimental factor was the presence or absence of enrichment of the birds’ cages: the nest box, scratcher, plastic corrugated pipe (tunnel), limestone cubes, sandbathing box and feeder box with a drilled cover. Quails were subjected to behavioural tests (tonic immobility and open field tests) and, after 6 weeks, blood samples were taken from them to determine their biochemical indices as well as their cortisol and corticosterone levels. An additional element was the assessment of fertility indices. The presence of enrichment was shown to reduce behavioural disturbances in Japanese quails. This study also found that the colour and shape of an object were very important regarding the birds’ interest in it. Additionally, individuals kept in enriched cages, who were allowed to exhibit their natural behavioural patterns, had lower stress levels.

Training level reveals a dynamic dialogue between stress and memory systems in birds

Chronic stress profoundly affects forms of declarative memory, such as spatial memory, while it may spare non-declarative memory, such as cue-based memory. It is known, however, that the effects of chronic stress on memory systems may vary according to the level of training of an individual was submitted. Here, we investigated, in birds, how chronic stress impact spatial and cue-based memories according to training level. For that, control and chronically stressed Japanese quail were trained in a task that could be solved using spatial and cue-based memory and tested for their memory performance after 5 and 15 training days (initial training and overtraining, respectively) and following an emotional challenge (exposure to an open field). Our results showed that, compared to control quail, chronic stress impacted negatively spatial memory performances in stressed birds after initial training, but these differences were lowered after overtraining. Control birds seemed to shift from spatial to cue-based memory to solve the task across overtraining. However, an emotional challenge before testing reinstated the negative impact of chronic stress on spatial memory performances between the groups, revealing that chronic stress/overtraining did not eliminate the spatial memory and differences caused by stressors can reemerge depending on the individual's immediate psychological state. Contrary to spatial memory, cue-based memory was not affected in chronically stressed birds compared to control birds in any test occasion, confirming its resistance against the negative effects of chronic stress. Altogether these findings reveal a dynamic dialogue between stress, training level, and memory systems in birds.

Expression of aggressiveness modulates mesencephalic c-fos activation during a social interaction test in Japanese quail (Coturnix japonica)

It is well known that during a social conflict, interactions are dependent on the animal's propensity to behave aggressively as well as the behavior of the opponent. However, discriminating between these two confounding factors was difficult. Recently, a Social Interaction (SI) test using photocastrated males as non-aggressive stimuli was proposed as a useful tool to evaluate aggressiveness. The avian Intercollicular- Griseum centralis complex (comparable to mammalian periaqueductal gray) has been reported as a crucial node in the descending pathways that organize behavioral and autonomic aspects of defensive responses and aggressiveness. Herein, using the SI test, we evaluated whether mesencephalic areas are activated (expressed c-fos) when photostimulated adult males are confronted with non-responsive (non-aggressive) opponents. Furthermore, we also examined whether mesencephalic activation is related to male performance during the SI test (i.e., aggressive vs. non-aggressive males) in birds reared in enriched or in standard environments. Five mesencephalic areas at two anatomic levels (intermediate and rostral) and locomotion during SI testing were studied. Aggressive males showed increased c-fos expression in all areas studied, and moved at faster speeds in comparison to their non-aggressive and control counterparts. Non-aggressive males and the test controls showed similar c-fos labeling. In general, rearing condition did not appear to influence c-fos expression nor behavior during the SI test. Findings suggest that mesencephalic activation is involved when males are actively expressing aggressive behaviors. This overall phenomenon is shown regardless of both the environmental stimuli provided during the birds´ rearing and the potentially stressful stimuli during the SI trial.

Atrazine induced oxidative stress and mitochondrial dysfunction in quail (Coturnix C. coturnix) kidney via modulating Nrf2 signaling pathway

Atrazine (ATR) is a most used herbicide which is believed as a pivotal determinant of environmental nephrosis, but potential mechanism is still largely unclear. This study intends to reveal a novel mechanism of ATR-induced nephrotoxicity. Quail were treated with 0, 50, 250 and 500 mg ATR/kg/d by oral gavage for 45 days. Kidney coefficient was decreased, biochemical and morphologic indices reflecting the kidney injury were significantly increased in ATR-exposed quail. ATR exposure upregulated the expression of proapoptotic factors (Bax, Caspase 3 and FasL) and downregulated antiapoptotic factor (Bcl-2). Notably, cristae of mitochondria decreased, mitochondrial malformation and mitochondrial vacuolar degeneration were observed in ATR-exposed quail. ATR induced the disorder of mitochondrial function related factors expressions and promoted oxidative damage. Furthermore, ATR induced toxicities in the expression of Nrf2 and Nrf2-target genes. In conclusion, ATR altered the microstructure and function of quail kidney. ATR induced renal damage via causing mitochondrial dysfunction, influencing mitochondrial function related genes expression, modulating Nrf2 signaling pathway. This study suggested ATR induced the nephrotoxicity via disturbing the transcription of mitochondrial function related factors and Nrf2 signaling pathway.

Effects of voluntary exercise on apoptosis and cortisol after chronic restraint stress in mice

[Purpose]

To determine whether voluntary exercise (wheel running) has the potential of relieving stress.

[Methods]

In this study, restraint stress with or without voluntary wheel running was performed for mice housed in individual cages. A total of 21 ICR male mice were assigned into control (CON), restraint stress with voluntary exercise (RSVE), or restraint stress (RS) without voluntary exercise groups (n = 7 each).

[Results]

No significant difference in body weight increase was found among the three groups, although CON and RS groups had a tendency of having smaller body weight increase compared to the RSVE group. No significant difference in the expression level of liver heat shock protein 70, Bcl-2, or p53 was found among the three groups. However, caspase-3 protein level in RS group was significantly higher than that in the other two groups. Blood cortisol concentration in RS was higher (p < 0.05) than that in RSVE or CON group. It was the lowest (p < 0.05) in the RSVE group.

[Conclusion]

Our findings suggest that apoptosis caused by chronic restraint stress might be suppressed by voluntary exercise in mice.

Environmental Enrichments for a Group of Captive Macaws: Low Interaction Does Not Mean Low Behavioral Changes

Environmental enrichment has been widely used to improve conditions for nonhuman animals in captivity. However, there is no consensus about the best way to evaluate the success of enrichments. This study evaluated whether the proportion of time spent interacting with enrichments indicated the proportion of overall behavioral changes. Six environmental enrichments were introduced in succession to 16 captive macaws, and interaction of the animals with them as well as the behaviors of the group were recorded before and during the enrichments. All of the enrichments affected the proportions of time spent in different behaviors. Macaws interacted more with certain items (hibiscus and food tree) than with others (a toy or swings and stairs), but introduction of the enrichments that invoked the least interaction caused as many behavioral changes as those that invoked the most. Moreover, feeding behavior was only affected by the enrichment that invoked the least interaction, a change not detected by a general analysis of enrichment effects. In conclusion, little interaction with enrichment does not mean little change in behavior, and the effects of enrichments are more complex than previously considered.