Management of dairy heifers: Can operant conditioning be an effective and feasible tool to decrease stress and ease animals' close contact and handling?

Besides health monitoring, a regular check of dairy heifers' growth rate is desirable, but it is rarely done because procedures that require restraint and handling can be associated with substantial stress for both animals and farmers. Inexperienced heifers, especially if they are highly responsive to humans, may find restraint and handling potentially aversive. This study investigated whether training heifers of different age and responsiveness toward humans (RTH), through operant conditioning, could reduce stress in animals, ease close contact and handling, and be feasible in terms of farmers' effort. We assessed 60 Holstein heifers of 2 age classes (young, n = 29, 291 ± 39 d; old, n = 31, 346 ± 62 d) according to the avoidance distance test and classified them as confident (n = 20), neutral (n = 21), or nonconfident (n = 19). Half of the heifers of each age and RTH class were trained (n = 29), whereas the other half was not (n = 31). The trained heifers were subjected to target training for 8 sessions and positively reinforced with feed to allow being touched on the muzzle, rump, and perineum. If a heifer refused positive reinforcement, the trainer stepped back as negative reinforcement. In the last week of the experiment, the effect of training on the reaction to handling was assessed in all heifers. We measured heart rate, root mean square of successive interbeat interval differences (RMSSD), and fecal cortisol metabolites (FCMet). The presence of behavioral distress signs was recorded as well. The avoidance distance test was performed a second time 24 h after the measuring session. All of the trained heifers, regardless of RTH class, successfully accomplished the target training task in 6 sessions, each spending on average 25.3 s per session. All of the trained heifers allowed touches on the rump and perineum at the end of the fourth session. Training nonconfident heifers required more time compared with the others. Trained heifers showed higher RMSSD than nontrained heifers (14.2 vs. 16.9 ms, respectively), indicating a lower vagal tone, and thus, a slightly lower stress level than nontrained heifers. Training did not lead to differences in HR, FCMet, or presence of stress behavioral signs. Nonconfident heifers had the highest mean baseline FCMet values compared with neutral and confident heifers (38.4 vs. 30.3 vs. 29.1 ng/g, respectively). Nonconfident heifers also showed the lowest value of FCMet 12 h after the measuring session (36.7 vs. 44.6 vs. 49.7 ng/g), likely due to a decreased responsiveness of the adrenal gland to a stressor. The average avoidance distance decreased between the beginning and the end of the experiment, especially for neutral and nonconfident heifers, regardless of whether they were trained or not. These results show how using operant conditioning on some heifers not only decreased their vagal tone, but also reduced the responsiveness to humans of all the animals, trained and not trained; in the latter case, this reduction was through nonassociative learning, such as habituation.

Long-term effects of early maternal deprivation on goat social behaviour.

Early maternal deprivation has been shown to disrupt goat kids' social behaviour and stress-coping strategy, and has long-term effects in other species like cattle. We studied the long-term effects of early maternal deprivation on 18-month-old goats. Seventeen goats were raised together with their dams (DR kids) and other lactating goats and kids, while 18 goats were separated from their dams three days after birth and artificially reared together (AR kids). Kids of both treatments were weaned around two to three months of age, grouped and raised together until this study 15 months later. Affiliative, playful, and agonistic behaviour was recorded by focal sampling in the home pen, when the focal goat had rejoined the herd after being physically isolated for 3 minutes, and after the focal goat was restrained and manipulated for 3 minutes. Behavioural observations were also conducted after the goats were introduced in groups of four in a herd of 77 unknown, lactating multiparous goats. Avoidance distance tests were performed in the home pen to assess the human-animal relationship. Salivary cortisol was measured before and after physical isolation, and faecal glucocorticoid metabolites were measured before and 24 hours after introduction in the lactating herd. In the home pen, AR goats were involved in less head nudging than DR goats, but other social behaviours or their behavioural and physiological response to the various stressful situations were not affected by their rearing treatment. Upon introduction in a DR lactating herd, most of the agonistic interactions observed were initiated by multiparous goats towards the introduced AR and DR goats alike. AR goats received more threats from the multiparous goats than DR goats, but were involved in less clashing than DR goats. AR goats showed less avoidance of familiar and unfamiliar humans than DR goats. Overall, previously AR and DR goats showed only a few differences in affiliative and agonistic behaviours in their home pen or after being exposed to different stressors 15 months later. Nonetheless, after being introduced into a multiparous goat herd, AR goats were still threatened more often than DR goats, and DR goats clashed more than AR goats, suggesting some persistent differences in their social abilities observed at an early age before and after weaning. As predicted, AR goats remained less fearful of humans than DR goats.

A randomized controlled trial assessing the effect of intermittent and abrupt cessation of milking to end lactation on the well-being and intramammary infection risk of dairy cows.

The objectives were to compare the effects of an intermittent milking schedule with a thrice daily milking schedule during the final week of lactation on the well-being, udder health, milk production, and risk of culling of dairy cows. We hypothesized that cows subjected to an intermittent milking schedule would experience less udder engorgement and pain, lower concentrations of fecal glucocorticoid metabolites (11,17-dioxoandrostanes; 11,17-DOA concentration) after dry-off, lower risk of an intramammary infection during the dry period, higher milk production and lower somatic cell count in the subsequent lactation, and lower culling risk compared with herd mates milked 3 times daily and dried off by abrupt cessation. In a randomized controlled field study, Holstein cows (n = 398) with a thrice daily milking schedule were assigned to treatment and control groups. The treatment consisted of an intermittent milking schedule for 7 d before dry-off (gradual cessation of milking, GRAD). Gradual-cessation cows were milked once daily until the day of dry-off, whereas cows in the control group (abrupt cessation of milking, APT) were milked 3 times daily until the day of dry-off. Udder firmness and pain responses of the udder 3 d after dry-off, as well as the percentage change in fecal 11,17-DOA concentration (3 d after dry-off compared with the dry-off day), were used to assess the well-being of the animals. Compared with cows in the GRAD group, the odds [95% confidence interval (CI)] of udder firmness were 1.55 (0.99-2.42) for cows in the APT group, and the odds of a pain response were 1.48 (0.89-2.44) for cows in the APT group. The least squares means (95% CI) of the percentage change in 11,17-DOA concentration were 129.3% (111.1-150.4) for the APT group and 113.6% (97.5-132.4) for the GRAD group. Quarter-level culture results from the periods before dry-off and after calving were compared, to assess the likelihoods of microbiological cure and new infection. Cows in the APT group had lower odds of a new intramammary infection in the dry period [odds ratio, 95% CI: 0.63 (0.37-1.05)], whereas we observed no meaningful differences in the microbiological cure likelihood among groups. The least squares means (95% CI) for somatic cell counts (log10-transformed) were 4.9 (4.8-5.0) in the APT group and 4.9 (4.8-5.0) in the GRAD group. The odds (95% CI) of clinical mastitis in the first 30 d postcalving were 1.32 (0.53-3.30) in the APT group compared with the GRAD group. We observed no meaningful differences in milk production at the first test date postcalving or the culling risk among groups. We conclude that the gradual-cessation protocol tested herein failed to significantly improve animal well-being, udder health, milk production, and survival in the tested study cohort. However, the observed differences in udder firmness, as well as the numerical differences in udder pain and the percentage change in fecal 11,17-DOA concentrations suggest that this line of research may be useful. Future research is needed to develop drying-off strategies that are appropriate for lowering milk production at the end of the lactation and improve animal well-being without compromising udder health.

[Heart rate and faecal cortisol metabolites measurements in horses at the Sechseläuten in Zurich]. / Messung von Herzfrequenzen und Kotcortisolmetaboliten bei Pferden am Zürcher Sechseläuten.

INTRODUCTION: The Zurich's Sechseläuten is a traditional festival of the Zurich guilds, in which around 500 horses take part. After a parade through the old town of Zurich, the riders gather at a big square to canter around a burning woodpile topped with an exploding effigy (the «Böögg¼). The level of stress experienced by the horses partaking in this event is subjected to increasing scrutiny. The aim of this study was to evaluate the stress load of the horses participating in the Sechseläuten procession more objectively by measuring heart rate and faecal cortisol metabolites. Twenty-three horse-rider pairs were voluntarily recruited from the guilds for participation in the study. For comparison purposes, three sections of the procession were simulated in terms of gait and distance travelled in a normal riding environment during a test day and observed during the Sechseläuten itself 16 days later: Counter march Bahnhofstrasse, parade Limmatquai and parade around the burning «Böögg¼. All horses were equipped with a heart rate measuring system with GPS tracking (Polar Team Pro®, Polar Electro Oy, Finland). Faecal samples for measuring cortisol metabolites were taken rectally immediately before and 24 hours after the events. Thirteen of the 23 horses were sedated during the Sechseläuten (Acepromazine, 0,1-0,2 mg/kg p.o.). The differences between the observation periods and groups (sedated/unsedated) were tested by analysis of variance (P.

INTRODUCTION: Le Sechseläuten de Zurich est une fête traditionnelle des guildes zurichoises à laquelle participent environ 500 chevaux. Après un défilé dans la vieille ville de Zurich, les cavaliers se rassemblent sur une grande place pour galoper autour d'un tas de bois en feu surmonté d'une effigie qui explose (le «Böögg¼). Le niveau de stress des chevaux participant à cet événement fait l'objet d'une attention croissante. L'objectif de cette étude était d'évaluer plus objectivement le niveau de stress des chevaux participant au cortège du Sechseläuten en mesurant la fréquence cardiaque et les métabolites fécaux du cortisol. Vingt-trois couples cheval-cavalier ont été recrutés volontairement dans les guildes pour participer à l'étude. À des fins de comparaison, trois sections du cortège ont été simulées en termes d'allure et de distance parcourue dans un environnement équestre normal lors d'une journée de test et observées ensuite pendant le Sechseläuten lui-même 16 jours plus tard: Contre-marche sur la Bahnhofstrasse, cortège sur le Limmatquai et chevauchée autour du «Böögg¼ en feu. Tous les chevaux ont été équipés d'un système de mesure de la fréquence un cardiomètre avec suivi GPS (Polar Team Pro®, Polar Electro Oy, Finlande). Des échantillons fécaux destinés à mesurer les métabolites du cortisol ont été prélevés par voie rectale immédiatement avant et 24 heures après les événements. Treize des 23 chevaux ont été mis sous sédation pendant le Sechseläuten (Acépromazine, 0,1­0,2 mg/kg p.o.). Les différences entre les périodes d'observation et les groupes (sédaté/non-sédaté) ont été testées par analyse de variance (P.

Heifers don't care: no evidence of negative impact on animal welfare of growing heifers when using virtual fences compared to physical fences for grazing.

Virtual fencing (VF) represents a way to simplify traditional pasture management with its high labour and cost requirements for fencing and to make better use of the 'beneficial' agronomic and ecological effects of livestock grazing. In this study, the VF technology (® Nofence, AS, Batnfjordsøra Norway) was used with Fleckvieh heifers to investigate possible welfare impacts on the animals compared to conventionally fenced animals when they were trained to respond correctly to the system. The Nofence® collars (attached to the neck of the heifers) send acoustic signals as a warning when the animals approach the VF line, which was set up by GPS coordinates within the Nofence®-App, followed by an electric pulse when they do not stop or return. The heifers had no experience with VF prior to the study. Two treatments (VF versus physical fencing (PF)) were applied to six groups of four heifers each (three groups per treatment) over three 12-day time replicates. One VF line separated the pasture of the VF group into an accessible or non-accessible area. The control group had a PF line. Both groups were equipped with Nofence® collars (deactivated for the PF group). The trial took place on two adjacent paddocks of 1 000 m2 each following a 12-day schedule which was divided into three sections: visual support of the VF line by a physical barrier (first 2 days), only virtual border without visual support, moving the VF line (on day 8). Each time replicate followed the next successively on different paddocks with two new groups of heifers, which were grazed 5 h daily. During the whole experiment, the behaviour of each of the four animals per group was continuously observed; 2 h a.m., 2 h p.m. Exclusion by the VF line was effective in our trial. None of the heifers crossed the virtual boundary, i.e. the time spent in exclusion zone was zero. The heifers received 2.70 ± 2.63 acoustic signals and 0.30 ± 0.36 electric pulses (mean ± SD) per heifer and hour during all time replicates. Main cattle behaviour on pasture was not affected by the fencing system. Live weight gain, herbage consumption and faecal cortisol metabolites also revealed no significant differences. The duration until the heifers restarted grazing after an electric pulse from the Nofence® collar was significantly shorter than after an electric pulse from the physical fence. We can summarise that in our study, cattle well-being on pasture was not negatively affected by VF compared to PF.

Effects of separated pair housing of female C57BL/6JRj mice on well-being.

In laboratory animal facilities, it is a common code of practice to house female mice in groups. However, some experimental conditions require to house them individually, even though social isolation may impair their well-being. Therefore, we introduced a separated pair housing system and investigated whether it can refine single housing of adult female C57BL/6JRj mice. Individually ventilated cages (IVC) were divided by perforated transparent walls to separate two mice within a cage. The cage divider allowed visual, acoustic, and olfactory contact between the mice but prevented interindividual body-contact or food sharing. Short- and long-term effects of the separated pair housing system on the well-being of the mice were compared with single and group housing using a range of behavioral and physiological parameters: Nest building behavior was assessed based on the complexity of nests, the burrowing performance was measured by the amount of food pellets removed from a bottle, and trait anxiety-related behavior was tested in the free exploratory paradigm. For the evaluation of the ease of handling, interaction with the experimenter's hand was monitored. Social interaction with unknown conspecifics and locomotor activity were investigated in a test arena. Moreover, body weight and stress hormone (metabolites) were measured in feces and hair. After the mice spent a day under the respective housing conditions, concentrations of fecal corticosterone metabolites were higher in separated pair-housed mice, and they built nests of a higher complexity when compared to single-housed mice. The latter effect was still observable eight weeks later. In week 8, separated pair-housed mice showed less locomotor activity in the social interaction arena compared to mice from the other housing systems, i.e., single and group housing. Regardless of the time of testing, pair housing improved the burrowing performance. Separated pair-housed mice were more difficult to catch than group-housed mice. Hair corticosterone, progesterone, and dehydroepiandrosterone concentrations changed with increasing age independently of the housing system. There were no effects of the housing systems on trait anxiety-related behavior in the free exploratory paradigm, voluntary interaction with the experimenter's hand, and body weight. Overall, the transfer to the separated pair housing system caused short-term stress responses in female C57BL/6JRj mice. Long-term effects of separated pair housing were ambiguous. On one hand, separated pair housing increased nesting and burrowing behavior and may therefore be beneficial compared to single housing. But on the other hand, locomotor activity decreased. The study underlined that the effects of the housing conditions on physiological and behavioral parameters should be considered when analyzing and reporting animal experiments.

The effect of transdermal flunixin meglumine on blood cortisol levels in dairy calves after cautery disbudding with local anesthesia.

The objective of this study was to evaluate the effect of the nonsteroidal anti-inflammatory drug transdermal flunixin meglumine (Finadyne Transdermal) on plasma cortisol, average daily weight gain, and standing and lying behavior of calves, when given at the time of disbudding combined with local anesthesia. A sedative was not used to minimize pharmacological interactions. Seventy-one female Holstein Friesian calves aged 13 ± 2 d, with an average weight of 48.9 ± 4.26 kg were enrolled in the study. All calves were randomly assigned to one of 3 treatment groups: (1) control group (CON, n = 27), (2) 1-flunixin group (1-FLU, n = 26) with a single administration of transdermal flunixin meglumine at disbudding, and (3) 2-flunixin group (2-FLU, n = 24) with 2 administrations of transdermal flunixin meglumine, the first treatment at disbudding and the second 6 h after disbudding. Although the CON group received a placebo, 1-FLU and 2-FLU received flunixin meglumine transdermally. To account for plasma cortisol changes due to manipulation and handling of the calves, a sham disbudding procedure was performed one week before disbudding took place. Sham disbudding was conducted by using a cold cautery dehorner applied to each horn bud for 10 s. Disbudding was performed in a similar way by using a hot cautery dehorner. Plasma samples were collected to measure the stress biomarker cortisol at 7 different time points. Body weights were measured 4 times in 2 wk. Standing and lying behavior was assessed via 3-dimensional accelerometer. During sham disbudding and disbudding mean plasma cortisol concentrations were 6.09 ± 2.5 ng/mL and 5.16 ± 2.8 ng/mL, respectively. Treatment tended to have an effect on plasma cortisol concentrations during sham disbudding and had an effect on plasma cortisol concentrations during disbudding. Plasma cortisol concentrations were affected by treatment 2 h after disbudding in comparison to CON group. Furthermore, there was a significant effect on plasma cortisol concentrations 6 h after disbudding in contrast to CON. A return to baseline plasma cortisol levels (initial concentrations) was not achieved in CON during disbudding. There was no statistical difference between average daily weight gain and the treatment procedure. Total lying time was not affected by treatment after disbudding. In conclusion, transdermal flunixin meglumine given at the time of disbudding combined with local anesthesia decreased concentrations of the stress biomarker cortisol, but a second dose 6 h after disbudding had no further effect on plasma cortisol levels.

[Cortisol concentrations in sheep before, during and after sham foot trimming on a tilt table - the suitability of different matrices]. / Kortisolkonzentrationen bei Schafen vor, während und nach der simulierten Klauenbehandlung im Kippstand ­ Eignung verschiedener Matrices.

INTRODUCTION: Matrices that can be collected non-invasively for quantification of a stress response in sheep have received little attention in the veterinary literature. This study examines the suitability of blood, tears and saliva for determining a stress response in sheep undergoing sham foot trimming on a tilt table. The cortisol concentration of blood, tears and saliva and the concentration of cortisol metabolites in faeces were measured in 13 healthy Meat Merino ewes once a day for six days. Sham foot trimming on a tilt table was used as the stressor and was done during a one-hour period on day 4; cortisol concentrations of blood and tears were measured at 0, 10, 20, 30, 40 and 60 minutes. Cortisol concentrations of blood (maximum at 30 minutes) and tears (maximum at 40 minutes) increased during the procedure and then decreased. There were significant correlations between cortisol concentrations of blood and tears (p = 0,04) during sham foot trimming (area under the curve, 0 to 60 minutes). Over the entire 6-day study period, significant correlations were seen between the cortisol concentrations of blood and tears (r = 0,55; p.

INTRODUCTION: Les marqueurs qui peuvent être collectés de manière non invasive pour quantifier une réponse au stress chez le mouton ont fait l'objet de peu d'attention dans la littérature vétérinaire. Cette étude examine la pertinence du sang, des larmes et de la salive pour déterminer une réponse au stress chez des moutons subissant un parage fictif des pieds sur une table basculante. La concentration de cortisol dans le sang, les larmes et la salive ainsi que la concentration de métabolites de cortisol dans les fèces ont été mesurées chez 13 brebis Meat Merino saines une fois par jour pendant six jours. Le parage fictif des pieds sur une table inclinable a été utilisé comme facteur de stress et a été effectué pendant une période d'une heure le jour 4; les concentrations de cortisol dans le sang et les larmes ont été mesurées à 0, 10, 20, 30, 40 et 60 minutes. Les concentrations de cortisol dans le sang (maximum à 30 minutes) et les larmes (maximum à 40 minutes) ont augmenté au cours de la procédure puis ont diminué. Il y avait des corrélations significatives entre les concentrations de cortisol dans le sang et les larmes (p = 0,04) lors du parage fictif des onglons (aire sous la courbe, 0 à 60 minutes). Sur l'ensemble de la période d'étude de 6 jours, des corrélations significatives ont été observées entre les concentrations de cortisol dans le sang et les larmes (r = 0,55 ; p < 0,001), le sang et la salive (r = 0,53 ; p < 0,001) et les larmes et la salive (r = 0,78 ; p < 0,001). La concentration fécale de métabolites de cortisol était significativement augmentée au jour 5 (p 0,05), mais la concentration de cortisol des autres supports n'a pas changé de manière significative au cours de la période d'étude de 6 jours. Le parage fictif des pieds sur une table basculante a été considéré comme un facteur de stress aigu chez les moutons en raison de l'augmentation des concentrations de cortisol dans le sang, des larmes et de l'augmentation des concentrations de métabolites de cortisol dans les selles. La concentration de cortisol dans les larmes était similaire à celle du sang et, par conséquent, la collecte de larmes représente une alternative viable et non invasive au sang pour les tests de cortisol. Le délai des pics entre la concentration maximale de cortisol dans les larmes et le sang doit être pris en compte lors de l'interprétation des résultats.

Endocrine changes related to dog domestication: Comparing urinary cortisol and oxytocin in hand-raised, pack-living dogs and wolves.

Dogs are exceptionally well adapted to life close to humans, and alterations in their endocrine system during the domestication process may be an underlying mechanism. In particular, it has been suggested that low circulating cortisol concentrations in conjunction with simultaneously high oxytocin concentrations may have resulted in dogs' increased docility ('selection for tameness' hypothesis) and heightened propensity to interact and form relationships with humans ('hypersociability' hypothesis) compared to wolves. To investigate this, we analyzed cortisol and oxytocin metabolite concentrations from urine samples of hand-raised, pack-living domestic dogs and their non-domestic relatives, grey wolves. Based on the hypotheses outlined above, we predicted lower cortisol but higher oxytocin concentrations in dogs than wolves. In contrast to our prediction, we found higher cortisol concentrations in dogs than wolves. However, oxytocin concentrations were higher in dogs compared to wolves although the effect was relatively small. Indeed, male dogs had the highest oxytocin concentrations while female dogs' oxytocin concentrations were comparable to wolves'. Feeding status, reproductive phase, and conspecific social interactions also significantly affected cortisol and oxytocin concentrations. Furthermore, we compared two methods of correcting for variable water content of urine samples. We discuss our results in light of physiological and behavioral changes during domestication and highlight the importance of accounting for confounding variables in future studies.

Stress as a facilitator? Territorial male impala have higher glucocorticoid levels than bachelors.

Territoriality is a common behavioural adaptation, widespread among ungulates. Here, we tested the hypothesis that territorial individuals have higher glucocorticoid concentrations than non-territorial bachelors, in wild impala (Aepyceros melampus) in the Serengeti ecosystem. We also investigated how the relationship between territoriality and glucocorticoid levels is influenced by environmental context, specifically, food quality, population density (i.e., territory defence intensity), and herd size (i.e., mate defence effort). We collected 139 faecal samples over 4 years and analysed these for faecal glucocorticoid metabolites (FGMs). We used Normalised Difference Vegetation Index (NDVI) as a proxy for food quality, and population density was based on aerial surveys. Territorial males had, on average, higher FGM concentrations than bachelors. Increased food quality did not affect FGM levels in territorial males, but decreased FGM levels in bachelors by 78%. Greater population density increased FGM levels by 47%, but this effect was not different between territorial and bachelor males. Herd size did not affect FGM levels in territorial males. While elevated GC levels are often suggested to be repercussions of being territorial, our findings support the hypothesis that elevated GC levels may be beneficial and act as a facilitator of a male's reproductive potential. The elevated GC levels may increase the ability of territorial males to maintain a territory by increasing energy mobilisation and metabolic rate, ultimately increasing their reproductive fitness. Appreciating that long-term increases in GC levels are not simply costly but may have an adaptive, potentially facilitating role in an animal's life history is key to understanding HPA-axis reactivity and its potential in eco-physiological studies.

Consequences of climate-induced vegetation changes exceed those of human disturbance for wild impala in the Serengeti ecosystem.

In East Africa, climate change is predicted to reduce vegetation quality, and pervasive human disturbance has already resulted in significant declines in biodiversity. We studied the combined effects of reduced forage quality and human disturbance on faecal glucocorticoid metabolite (FGM) concentrations. We predicted that decreasing nutritional quality and increasing human disturbance would have an additive positive effect on FGM levels in wild impala (Aepyceros melampus). Employing a space-for-time approach, we used normalized difference vegetation index (NDVI) as a measure of forage quality, combined with spatially explicit proxies of human disturbance across areas of different protection management strategies in the Serengeti ecosystem. We collected 639 faecal samples, spread over 4 years, including both wet and dry seasons. Impala FGM levels increased significantly with declining NDVI and, to a lesser extent, with increasing proxies for human disturbance. However, we found no interaction between the two, such that impala had elevated FGM levels with low NDVI and low FGM levels with high NDVI regardless of human disturbance levels. This implies that impala will have high FGM levels if forage quality is poor, even with significant protection and reduced human disturbance. Understanding how animals respond to and cope with changes in forage quality and human land use across different protected areas is important for conservationists and managers to better protect species at risk and predict population viability.

Salivary cortisol responses to acute stress vary between allergic and healthy individuals: the role of plasma oxytocin, emotion regulation strategies, reported stress and anxiety.

Numerous studies have demonstrated that acute psychological stress, induced by the Trier Social Stress Test (TSST) paradigm, affects salivary cortisol secretion and self-reported stress measures including anxiety. Allergy has been related to altered cortisol responsiveness and increased stress vulnerability. Here, we investigated acute stress responses and emotion regulation strategies in cohorts of allergic and healthy individuals. Groups of allergics and healthy individuals were subjected to the TSST and experienced levels of stress and anxiety, as well as emotion regulation strategies, were assessed. Cortisol and oxytocin concentrations were measured in saliva or plasma. The present findings confirm earlier results of altered stress responsiveness in allergic individuals. Acute stress by the TSST evoked higher physiological arousal in allergics by means of salivary cortisol secretion. Allergics also scored higher on emotion suppression. However, individuals who were more likely to use reappraisal recovered more efficiently from the cortisol increase. No such effect for reappraisal was found in the healthy population. No differences in self-reported anxiety and stress emerged between the groups. Plasma oxytocin levels prior to the TSST were significantly higher in allergics. Our data corroborate earlier findings on altered stress susceptibility in allergics. Moreover, we identified differences in emotion regulation and oxytocin secretion which should be further explored. Accounting for the emerging global prevalence of allergy, more in-depth research into the experience of stress, coping strategies and stress-related molecules in allergic people is warranted.Short summaryThis study addressed stress experiences and emotion regulation in allergic and non-allergic adults. Allergics scored higher on emotion suppression, had higher pre-stress concentrations of plasma oxytocin and exhibited a stronger salivary cortisol response to stress than healthy people. The research outcomes indicate that allergic individuals cope less efficiently with acute stress but may benefit from adaptive emotion regulation strategies such as reappraisal.

Herd-level associations between human-animal relationship, management, fecal cortisol metabolites, and udder health of organic dairy cows.

Impact patterns of human-animal relationship (HAR) and herd stress level on udder health were investigated in a cross-sectional study on 30 German and Danish organic dairy herds also taking into account influencing factors regarding housing and management. Cow behavior (avoidance distance, tolerance to tactile interaction, release behavior) was assessed in tests, milkers' behavior recorded during milking, and information about contacts with animals during routine work gathered by interview. Additionally, stockpersons' attitudes were recorded via questionnaires. Fecal cortisol metabolites were measured in approximately 30 focal cows on each farm and used as a proxy to determine the level of distress within the herd. Management and housing were assessed on-farm. The following herd udder health indicators were calculated: the prevalence of mastitis quarters (≥100,000 cells/mL), and, from milk recording data over 1 yr retrospectively, the average somatic cell score and the self-cure rates during lactation per herd. Multivariable regression models with stepwise selection were calculated at herd level. The following HAR-related factors were associated with better udder health (in at least 1 of the final models): stockpersons' higher agreement on patience being important when moving the cows and on necessary contact to cows being pleasant, higher amount of positive interactions with cows during milking, more docile cows in the release behavior test, no routine change of milkers, more contact time during routine work, no active heifer habituation to milking, and performance of barn controls beyond routine work. Lower fecal cortisol metabolite levels were related to higher self-cure rates during lactation. Concerning housing, management, and herd characteristics, the following known factors were related to impaired udder health for at least 1 of the indicators: straw yards, automatic milking system, higher average lactation number, and less antibiotic udder treatments. The results confirm earlier findings that HAR is associated with udder health and should therefore be considered in future research and mastitis control programs. First indications of negative associations between herd stress level and mastitis curing capacity should be followed up in future studies.

An exploratory study of competition scores and salivary cortisol concentrations in Warmblood horses.

The main objective of this explorative study was to describe the relationship between competition scores and salivary cortisol concentrations in young horses during dressage and showjumping competitions. The study also investigated whether the diurnal rhythm of salivary cortisol concentrations was affected by competition over consecutive days compared with the home environment. Saliva samples were collected from 126 dressage horses and showjumpers in their home environment and at 3 different events. The relationship between scores given by judges at the competition and cortisol concentrations at the event was assessed. The results demonstrated that competition scores correlated positively to baseline cortisol concentrations at one of 3 events (r = 0.53, P < 0.001). Salivary cortisol concentrations followed a diurnal rhythm with the highest concentrations measured in the morning and the lowest in the evening, both at home and in the competition environment (P < 0.05). Salivary cortisol concentrations were greater during the competitions than at home (P < 0.05) except at one event where showjumpers did not increase between home and competition. Dressage horses had the highest baseline cortisol concentrations at competition, and exercise caused cortisol concentrations to increase in both showjumpers and dressage horses (P < 0.001). In conclusion, the diurnal rhythm in salivary cortisol concentrations was maintained in the novel environment. Dressage horses demonstrated greater baseline cortisol concentrations at competition than showjumpers, suggesting that they may perceive the novel environment as more stressful. Furthermore, there was no consistent relationship between baseline salivary cortisol concentrations and competition scores across the events.

Clinical parameters and adrenocortical activity to assess stress responses of alpacas using different methods of restraint either alone or with shearing.

Shearing of alpacas is stressful and is undertaken by restraint in the standing position, cast on the floor or on a tilt table. The objectives of the study were to evaluate and compare the stress responses between different methods. The study consisted of two parts. In part one, 15 animals were restrained applying all three methods but without shearing. In part two, 45 animals in three groups of 15 were shorn using one of the three procedures. Body temperature, heart rate, respiratory rate, salivary cortisol and faecal cortisol metabolites (FCM) were measured. Part 1: restraint in a standing position was less stressful than other procedures. Part 2: the classic clinical parameters changed significantly over time but without significant differences between the methods. The number of injuries did not differ. Saliva cortisol and FCM concentrations varied in wide ranges between animals. An increase in FCM concentrations occurred in all groups but saliva cortisol concentration increased only after shearing on the ground. The recommendations of the study are to shear calm alpacas in the standing position but animals showing severe defence reactions should be shorn either cast on the ground or on a table to decrease the risk of injuries.

Short communication: Pilot study on hormonal, metabolic, and behavioral stress response to treatment of claw horn lesions in acutely lame dairy cows.

Short-term effects of therapeutic claw trimming in acutely lame cows (n=21) with nonadvanced claw horn lesions on the endocrine, metabolic, and behavioral stress responses were investigated in comparison to regular claw trimming in nonlame control cows (n=21). Controls were matched to lame cows by parity and stage of lactation. Lame cows suffering from typical sole ulcers or white line disease were blinded and randomly assigned to 2 treatments, receiving 15 min before interventions either ketoprofen (n=11; 3mg/kg of BW intramuscularly; Romefen, Merial, Lyon, France) or placebo (n=10; saline in equivalent amount and route of administration). All cows underwent functional claw trimming in lateral recumbency on a surgical tipping table, and claw horn lesions in lame cows were conventionally treated (removal of loose horn, block on opposing claw, bandaging of affected claw). Blood samples collected 15 min before, at the end, and 24h after claw trimming were analyzed for concentrations of cortisol, fatty acids, lactate, and glucose, and fecal samples (collected before treatment and after 24 h) for cortisol metabolites. Behavioral stress responses during functional and therapeutic claw trimming were recorded. Concentrations of blood cortisol, fatty acids, glucose, and fecal cortisol metabolites were higher in lame than in nonlame cows after treatment. During claw treatment, more leg movements were recorded for lame cows than nonlame cows. Pre-emptive administration of ketoprofen had no obvious effects on stress responses to therapeutic claw trimming. Treatments of claw horn lesions caused a significant stress and pain reaction in acutely lame cows, demonstrating the necessity of adequate pain management protocols for such interventions.

Effects of season, age, sex, and housing on salivary cortisol concentrations in horses.

Analysis of salivary cortisol is increasingly used to assess stress responses in horses. Because spontaneous or experimentally induced increases in cortisol concentrations are often relatively small for stress studies, proper controls are needed. This requires an understanding of the factors affecting salivary cortisol over longer times. In this study, we have analyzed salivary cortisol concentration for 6 mo in horses (n = 94) differing in age, sex, reproductive state, and housing. Salivary cortisol followed a diurnal rhythm with the highest concentrations in the morning and a decrease throughout the day (P < 0.001). This rhythm was disrupted in individual groups on individual days; however, alterations remained within the range of diurnal changes. Comparison between months showed highest cortisol concentrations in December (P < 0.001). Cortisol concentrations increased in breeding stallions during the breeding season (P < 0.001). No differences in salivary cortisol concentrations between nonpregnant mares with and without a corpus luteum existed. In stallions, mean daily salivary cortisol and plasma testosterone concentrations were weakly correlated (r = 0.251, P < 0.01). No differences in salivary cortisol between female and male young horses and no consistent differences between horses of different age existed. Group housing and individual stabling did not affect salivary cortisol. In conclusion, salivary cortisol concentrations in horses follow a diurnal rhythm and are increased in active breeding sires. Time of the day and reproductive state of the horses are thus important for experiments that include analysis of cortisol in saliva.

Immobilization stress sensitizes rat dorsal horn neurons having input from the low back.

BACKGROUND: Stress is known to promote several forms of muscle pain including non-specific low back pain. However, the question if stress alone activates nociceptive central neurons has not been studied systematically. Here, we investigated the influence of repeated immobilization stress on dorsal horn neurons and behaviour in the rat. METHODS: The stress consisted of immobilization in a narrow tube for 1 h on 12 days. Single dorsal horn neurons were recorded with microelectrodes introduced into the spinal segment L2. In this segment, about 14% of the neurons responded to mechanical stimulation of the subcutaneous soft tissues of the low back in naïve rats. The neurons often behaved like wide dynamic range cells in that they had a low mechanical threshold and showed graded responses to noxious stimuli. RESULTS: The stress-induced changes in neuronal response behaviour were (1) appearance of new receptive fields in the deep tissues of the hindlimb, (2) increased input from deep soft tissues, but unchanged input from the skin and (3) significant increase in resting activity. Surprisingly, the pressure-pain threshold of the low back remained unchanged, although dorsal horn neurons were sensitized. In the open field test, the rats showed signs of increased anxiety. CONCLUSIONS: This study shows that stress alone is sufficient to sensitize dorsal horn neurons. The data may explain the enhanced pain low back patients report when they are under stress. The increased resting discharge may lead to spontaneous pain.

Welfare and performance in layers following temporary exclusion from the litter area on introduction to the layer facility.

When introduced to the laying facility, pullets are sometimes temporarily excluded from the litter area in order to help them locate food and water, and to prevent floor-laid eggs. This procedure is not permitted in Sweden, because it involves denying access to both litter and space, which may have a negative effect on bird welfare. The present study investigated how the welfare and performance of layers were affected by this temporary exclusion on introduction of hens to the laying facility. The study included 600 floor-reared Dekalb White layers obtained at 16 wk age and housed in 6 groups of 100 in a conventional single-tier floor-laying system. Birds were either given full access to the litter area during the whole study or were excluded from the litter area during the first 2 wk after transfer to the laying facility. From 18 to 72 wk age, birds in both treatments had full access to the litter area. Excluding birds from the litter area for 2 wk resulted in better feather cover and reduced fearfulness, according to novel object and tonic immobility tests. Furthermore, birds initially excluded from the litter area produced eggs with a lower proportion of shell irregularities than birds with full access to the litter area throughout. No difference was found in corticosterone metabolites in droppings rate of lay, mortality, or proportion of floor-laid eggs. In conclusion, none of the parameters studied indicated that the welfare of laying hens was compromised by temporary exclusion from the litter area on introduction to the laying facility. In fact, some of the data suggested that bird welfare had improved.

Assessment and refinement of intra-bone marrow transplantation in mice.

Intra-bone marrow transplantation (IBMT) may improve the seeding efficiency of transplanted hematopoietic stem cells compared to the routinely used intravenous injection. Current IBMT protocols are optimized for ease of use and to improve experimental results. However, there have been no investigations to assess the impact of IBMT on animal welfare. Here, we report the results of pain assessment after IBMT and the effects of refinements to the current standard procedure. IBMT was performed in either the tibia or the femur of a recipient mouse under general anesthesia. Impact was determined using clinical scoring of different parameters (lameness, grip capacity, body weight loss, footprint analysis), behavioural tests (burrowing, open-field), monitoring of stress hormones and post-mortem histology. The results revealed that IBMT definitely induces severe post-operative distress. Although IBMT in the tibia is technically easier, the degree of impairment and the distress observed were consistently higher than for transplantation in the femur. A refinement for IBMT in the tibia was achieved by using 30- instead of 26-gauge needles and by sparing the patellar tendon. Consequently, for IBMT, we recommend either using the femur, or if the tibia is required due to its better feasibility, using our refined protocol. Furthermore, IBMT should definitely be limited to one leg per animal.