Applied Animal Behaviour Science最新文献

Behavioral variation among individuals is ascribed to the species' biology and the life history of each one. Many study areas consider individual differences, acknowledging their significant impact on fitness. Although boldness remains the most extensively studied behavioral dimension of individual differences in animals, ongoing debates persist regarding the evaluation of behavioral consistency over time and between contexts, as well as the determination of which features are crucial for delineating profiles. In this study, we investigated which behavioral traits explain the profiles of shyness and boldness and assessed their temporal and contextual consistency. For this, we divided zebrafish into bold and shy profiles by applying an emergence test (black-to-white entrance) three consecutive times with the same population of fish. The two groups formed (bold and shy) went through five different behavioural tests: novel tank, open field, black and white preference, aggressiveness, and sociability, which were employed twice, with an interval of 30 days. Bold animals showed less anxiety-like behaviour and higher aggressiveness compared to shy animals, and this pattern remained consistent over time for the two contexts. This suite of related behavious were considered the main factors to classify zebrafish into bold and shy profiles. In addition, the consistency appeared to be context dependent. The differences noted in the behavioural profiles allowed us to understand aspects of behavioural syndromes and how individuals behave when facing environmental challenges in different situations.

Increased turbidity due to Palm Oil Mill Effluent (POME) contamination has been reported in several water bodies. However, the impact of POME-derived turbidity on the reproductive behaviour of fish is still unexplored. Hence, this study was aimed to investigate the alteration in reproductive behavior of siamese fighting fish (Betta splendens) after exposure to different levels of turbidity derived from POME. In total, 12 sexually mature pairs of siamese fighting fish were exposed to the different levels of turbidity, namely <1 NTU (control), 20 NTU (Treatment A), 40 NTU (Treatment B), and 60 NTU (Treatment C) with three replicates. Reproductive performance (total released egg, relative weight of released eggs, and nest area) and behaviour parameters (fin spreads, tail beats, chasing, leads, circling, and copulation) were measured. Results showed that an increase in turbidity (>40 NTU) due to POME contamination significantly decreased total released egg but did not have significant impact on relative weight of released eggs and nest area. Decreased total released eggs was occurred due to several alterations in the reproductive behaviour of siamese fighting fish during both the premating and mating stages. Duration of premating and mating stage was significantly decreased at turbidity level of 60 NTU. During premating stage, the number and average time of fin spreads behaviour at turbidity level of 60 NTU were significantly increased. In addition to, the number of chasing behaviour was significantly decreased with increasing turbidity levels. Furthermore, several alterations in reproductive behavior was also observed in mating stage, including increasing number and average time of lead, copulation interval, number of tail beat, average time of lead, and average time of circlings, followed by decreasing number of leads and number of circlings. In addition to, number of copulation and eggs per copulation showed an increasing and decreasing pattern at turbidity level of 40 and 60 NTU, respectively. The study suggests that reproductive behavior of fish might consider as alternative approach to support POME remediation management, mainly for turbidity parameters.

Consistent individual differences (CIDs) in animal behavior, also known as personality or temperament, are measured in a variety of assays and are presumed to represent relatively stable traits of individual animals. Because these behaviors are presumed to represent stable traits, repetition of assays over short and long-term time frames and contexts is crucial; such repetitions are not commonly achieved in literature regarding the topic of CIDs, especially not in a singular study. In beef cattle, CIDs are often related to feeding and social preferences, which is relevant for extensively managed herds of ruminants. This study investigated the consistency of behavior among 50 breeding Angus x Hereford cows across repetitions within one year and over one year during three distinct contexts: handling and isolation in a chute corral system, choice in a social-feed tradeoff test, and response in a novel bucket approach test. We found that cows were consistent across short-term (assessed with repeatabilities [R]) and long-term (assessed with correlations across multivariate models [r]) timeframes in durations of behaviors exhibited in the management context (e.g. while handled [R = 0.60, r = 0.39], while traversing a cement chute [R = 0.69, r = 0.67] and an open squeeze stall [R = 0.76, r = 0.85]). Repeatable behaviors from the handling and isolation in chute system context were input into PCA with varimax rotation. Behaviors loaded onto three principal components that explained 66 % of the variance in the data and distinguished cows along axes of activity, fearfulness and excitability. Cows that were deemed less active (p = 0.010) and less excitable (p = 0.039) chose to approach the supplement bucket over gaining proximity to conspecifics in a social-feed tradeoff test. Even though the cows were not restrained in a squeeze stall, consistent individual differences in behavior across short (within year) and long-term (between years) timeframes were found. This suggests that future research can use unrestrained methods to evaluate cattle temperament, which could improve animal welfare and safety of handlers during experiments. Passive and less excitable beef cattle were more feed-centric, indicating that CIDs in behavior assays could potentially be used to predict feeding behavior because of an underlying stable trait in cows that ties response to handling and management with feed choice in a social-feed tradeoff task.

The Bengal slow loris (Nycticebus bengalensis) is one of the most confiscated and rescued primate species in China. These animals are often subject to physical issues due to poor husbandry practices in captivity. Many individuals rescued from the illegal wildlife trade are confined to captivity, leading to decreased locomotion ability and increased abnormal behavior. Recognizing the potential benefits of rehabilitation exercises, we conducted outdoor rehabilitation activities in forest environments to improve the locomotion performance of rescued Bengal slow lorises, and evaluated how individual characteristics and conditions in captivity influenced their locomotion recovery. The results of the rehabilitation exercises were promising, showing that the animals exhibited more elaborate route selection, improved action scores, longer distances traveled, and reduced periods of inactivity. Bengal slow lorises housed in larger cages and those in short-term captivity demonstrated better overall performance. Additionally, animals displaying stereotypical behavior achieved higher action scores, while male lorises had longer periods of motionlessness compared to females. These findings highlight the positive impact of rehabilitation exercises on the locomotion abilities of captive Bengal slow lorises, emphasizing the importance of enhancing animal welfare and implementing scientifically informed strategies for the successful reintroduction of pre-released animals.

Undesirable companion dog behaviours negatively impact the lives of both owners and dogs. Therefore, it is imperative that behaviour modification interventions are researched to establish effectiveness. Counterconditioning is commonly recommended for modification of a broad range of undesirable dog behaviours, however, to date, no comprehensive review has investigated the effectiveness of this technique. This study aimed to evaluate the existing literature on counterconditioning interventions for dog behaviour modification, adopting broad inclusion criteria. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 12 peer-reviewed papers and 2 dissertations were identified. A review of these 14 studies found that there were discrepancies in the definitions and applications of counterconditioning-based interventions. These discrepancies were based on the contingency with which dogs received reinforcement and could be categorised into classical and operant counterconditioning methodologies. The majority of the studies resulted in positive outcomes, particularly when addressing undesirable kennel behaviours and aggressive behaviours towards other dogs or household visitors. However, separation-related behaviours were found to be more resistant to change. Furthermore, heterogeneity in intervention techniques, reliance on expert implementation or instruction, and small sample sizes, limit the generalisability of the results. Our review confirms the effectiveness of counterconditioning in reducing undesirable dog behaviours, however it is essential that future studies clearly detail all aspects of the intervention, such that methodologies can be accurately understood, applied, and compared. Future research should also focus on increasing sample sizes and including physiological measures of stress of participating dogs.

Commercial poultry are typically fed diets with fatty acid compositions that differ considerably from wild-type diets in the omega-6 to omega-3 FA ratio (n-6: n-3). Maternal dietary n-3 FA have been shown to affect offspring brain development and cognition in various avian and mammalian species. This study explored the effects of feeding egg-type layer breeders with flaxseed on the performance of their female offspring in a three-stage discrimination task. Shaver White and ISA Brown breeders were fed either a control diet (n-6: n-3 = 14.7:1) or a flaxseed-enriched diet (n-6: n-3 = 5.3:1) throughout the rearing and laying phases. At 30 and 36 weeks of age, eggs were collected, incubated and hatched. Offspring were housed in enriched floor pens and received a control diet. At 12 (pullets) and 33 (hens) weeks of age, three learning tasks were conducted: behavioural shaping (N=437), discrimination test (N=350), and reversal learning (N=213). Food rewards (sweetcorn and raisins) were placed in the “reward” cup. Behavioural shaping consisted of five phases (P): P1 clear cup, P2 coloured cup, P3 coloured cup half-covered with a lid, P4 coloured cup three quarter covered with a lid, and P5 coloured cup covered with a lid. One cup, alternating between blue and green, was presented. Chickens had to eat the food reward from the cup in 4/5 trials to pass each phase. Two cups (green and blue) were presented during discrimination testing and reversal learning with food only in the predetermined “reward” cup. Learning criterion was choosing the correct cup in 4/5 trials for three consecutive days in discrimination testing and for two consecutive days in reversal learning. Data were analysed using survival class analyses. The hazard ratio (HR), 95% confidence intervals (CI) [LL, UL] and p-values to determine the probability of reaching learning criteria are reported. In P1 of behavioural shaping, Brown hens were likelier to reach criteria (HR=2.28, 95% CI [1.48, 3.55], p<0.001). For overall success in behavioural shaping (P1–5), hens were likelier to reach criteria than pullets (HR=2.42, 95% CI [1.50, 3.91], p<0.001). White chickens were likelier to reach criteria in the discrimination test than Brown chickens (HR=1.03, 95% CI [1.01, 1.75], p=0.04). Finally, pullets were likelier to reach criteria in reversal learning than hens (HR=0.44, 95% CI [0.23, 0.86], p=0.016). These results show that age, strain, and their interaction, but not maternal n-3 FA diet, affected the success of chickens in learning tasks.

Competition for feed in a group of gestating sows leads to aggression around feeding stations, which has a negative impact on their welfare. This study investigates the potential of teaching gestating sows an individual sound signal to reduce aggression resulting from competition for feed access, and thus improve their welfare in a group. A total of 32 sows were used. In a test room, “learning” sows (n = 16) went through 4 individual learning phases (27 days in total) to associate the individual sound signal with an invitation to feed from a one-way feeding station and to discriminate this individual sound signal from other unknown sound signals. After the learning phases, sows were subjected to a 3-day evaluation phase in groups of 4 sows. The "naive" sows (n = 16) were also introduced to the test room individually for 18 days, and in groups of 4 for 3 days without following the learning procedure. Learning sows correctly responded to 100% of their individual sound signal after only 8 days of individual learning, suggesting that they successfully associated the sound signal with feed access. Distinguishing between different sounds was harder as shown by only 18.8% of success after an unknown sound emission at the end of the individual learning phases. Naïve sows reduced the time spent in the feeder compared to learning sows (P < 0.001). On the second day of the group phase, learning sows were less aggressive than naïve sows (P < 0.05). Compared to high-ranking sows, low-ranking sows displayed a reduced number of spontaneous approaches to the feeder during the last individual learning phase (P < 0.001), and higher success rates in the group phase (P < 0.05). The study suggests that, for group-housed sows fed by an individual feeder, teaching sows an individual sound signal can modify their feeding and social behaviors, enhancing their overall well-being during feeding time. Furthermore, the results suggest that this individual learning may be particularly beneficial for low-ranking sows.

Across animal welfare science there is a lack of validated models of positive affective states. Previous work has shown that presentation of contrastingly valenced ultrasonic vocalisations (USVs) to rats alters their behaviour. However, the potential of using playback of USVs to induce a positive affective state and promote positive animal welfare has yet to be explored. We used three cohorts of juvenile male Wistar rats (37 days old) in three independent experiments to develop a novel home cage playback paradigm to induce a positive affective state in rats. The intention behind this paradigm was to create a low-stress environment, given the heightened susceptibility of positive affective states to stress. Rats were presented in pairs with a playback track consisting of positively valenced 50-kHz USVs, White Noise (within the 30 – 100 kHz range), or Background Noise in their home cage. In Experiments 1 (N = 7 cages) and 2 (N = 14 cages), rats received a single presentation of each playback track in a Latin square experimental design. In Experiment 3 (N = 20 cages), rats received repeated presentations of the same playback track over five consecutive days. Changes in affective state were measured through USV production, approach to the stimulus, and play behaviour. Across all three experiments, the presentation of 50-kHz stimuli USVs increased subject-produced positively valenced 50 kHz USVs compared to presentation of Background Noise (e.g. Experiment 2; F_2,239 = 6.05, p < 0.05). Similarly, rats also expressed an increase in approach behaviour towards the speaker in response to 50 kHz stimuli USVs compared to White Noise and Background Noise (Experiment 3 duration of approach behaviour; F2,479 = 10.55, p < 0.001). Whilst there was complexity in the relationship between the presentation of different acoustic stimuli and play behaviour, rats presented with the 50 kHz stimuli showed increased social play in the ten minutes during presentation under some of our test conditions. The impact of acoustic stimuli on measures of affective state across cohorts provides evidence that the home cage playback paradigm holds promise as a method for inducing a positive affective state in rats.