Review: Rethinking environmental enrichment as providing opportunities to acquire information.

Environmental enrichment, that is making the environment of animals more complex, was first designed to enhance the welfare and cognitive abilities of captive animals, and was more recently applied to farm animals. Enrichments can be sensory, physical, social, occupational, feeding-based, or a mix of these, with a view to improve animals' welfare. We posit that enrichments share the common factor of providing information to animals so that enrichment is all about providing the animal with a way to acquire information by interacting with the environment. Animals enjoy acquiring information, and the process of acquiring information acts in a way that enables them to better adapt to future environments. This reframed view of enrichment has several implications including prolonging the duration of exposure to an enrichment does not necessarily increase the impact of that enrichment, neutral and even slightly negative stimuli may still be enriching, complex and variable environments are enriching, and the more intensively an animal can engage with the environment, the more it will benefit from enrichments. These implications should be further explored by comprehensive re-analyses of findings from the enrichment literature and/or by dedicated experiments.

Improvement of the Welfare Quality scoring model for dairy cows to fit experts' opinion.

After several years of implementation, the original Welfare Quality scoring model for dairy cows appears to be highly sensitive to the number and cleanliness of drinkers and not enough to the prevalence of diseases, and as a consequence may not fit the opinion of some animal welfare experts. The present paper aims to improve the Welfare Quality calculations for the criteria 'Absence of prolonged thirst' and 'Absence of disease' in dairy cows, so that the results are more sensitive to input data and better fit experts' opinion. First, we modified the calculation of 'Absence of prolonged thirst' by linearising the calculation for drinkers' availability to avoid threshold effects. Second, we modified the calculation of 'Absence of disease' by applying a Choquet integral on the three lowest spline-based scores for each health disorder to limit compensation between health disorders. Third, we performed a global sensitivity analysis of the original and the alternative scoring models. Fourth, we compared the results obtained with the original and the alternative models with eight experts' opinions on two subsets composed of 44 and 60 farms, respectively, inspected using the Welfare Quality protocol and on which experts gave their opinion on the overall level of animal welfare. Results show that the alternative model significantly reduced the 'threshold effects' related to the number of drinkers and the compensation between health disorders. On the first subset, the alternative model fits the experts' opinion slightly better than the original model (P = 0.061). On the second subset, the models performed equally. In conclusion, the proposed refinements for calculating scores are validated since they significantly reduced 'threshold effects' and the influence of measures related to drinkers. It also reduced the compensation between health disorders by considering only the three lowest scores and thus increasing the influence of measures related to health disorders, and slightly improve at overall score level the accordance with experts' opinion.

Association between breeding bulls' reactivity to humans or handling and their daily behaviour and growth.

In beef cattle, reactivity to humans or handling by humans is considered a safety issue for farmers and to impact on productivity. Several testing procedures, associated with potential risks for both humans and animals, have been developed, involving simple human approach, free animals individually handled, or restraint in handling facilities. We investigated how such tests may be related to each other and which dimensions they reveal. Of particular interest is the tolerance towards human approach or handling involving human or chute restraint, and whether they could be linked to the daily activity of animals and their growth, potentially enabling this activity to be used as a proxy for evaluating this reactivity to humans and handing. We observed 498 Limousin breeding bulls, of up to 14 months of age, at a bull testing station during standardised behavioural tests involving humans and handling: human approach at the feed barrier or out of the home pen during individual morphological evaluation, docility test where the experimenter attempts to maintain the bull in the corner of a test pen, and during restraint in a chute for weighing. Routinely collected on farm at approximately 8 months of age, bulls' reaction scores to human approach were also available. The animals wore MEDRIA collars with 3D-accelerometers that continually monitored their daily activities (ingestion, rumination, rest, etc.). Three 2-week periods spanning 4 months were analysed. We conducted a varimax-rotated principal component analysis (PCA) on behavioural tests: the first component (23.63% of the variability) summarised scores during restraint in the chute, and the second component (19.36% of the variability) summarised avoidance distance score at the feed barrier, score during morphological evaluation, and docility score. The daily activity of the bulls was consistent across the three 2-week periods that were analysed and was not related to the PCA dimensions (P > 0.1). Animals that could be approached at a closer distance reached a heavier weight at the age of 400 days (P < 0.001). In conclusion, within the limits of the test used, breeding bulls' reactivity to humans or handling comprised at least two dimensions: reactivity to human approach and reactivity to restraint (in the chute); which cannot be predicted from the animal's daily activity. A bull's acceptance of being approached by humans was positively related to its growth.

Review: Assessment of dairy cow welfare at pasture: measures available, gaps to address, and pathways to development of ad-hoc protocols.

Pasture is generally perceived as positive for dairy cow welfare, but it nevertheless exposes cows to heat, parasites, and other challenges. This review is intended for people ready to design comprehensive protocols for assessing the welfare of dairy cows at pasture. We provide an overview of the benefits and risks of pasture for cows, and then go on to identify the available and feasible measures for assessing cow welfare at pasture and the gaps that need to be addressed to develop specific welfare measures. Some of the measures from on-farm welfare assessment protocols designed for indoor use (e.g. Welfare Quality®) are relevant for cows at pasture (e.g. lameness scoring). However, the timing, location and/or method for certain measures (e.g. observation of social behaviour) need to be adapted to the pasture context, as cows at pasture can roam over a large area. Measures to address specific pasture-related risks (e.g. heat stress, biosecurity) or benefits (e.g. expression of a wide range of behaviours) should be implemented in order to capture all dimensions of cow welfare at pasture. Furthermore, cow welfare is liable to vary over the grazing season due to changes in weather conditions, grass quality and pasture plots that induce variations in lying surface conditions, food availability, distance to walk to the milking parlour, and so on. It is therefore important to investigate the variability in different welfare measures across the pasture season to check whether they hold stable over time and, if not, to determine solutions that can give an overview across the grazing season. Sensors offer a promising complement to animal and environment observations, as they can capture long-term animal monitoring data, which is simply not possible for a one-day welfare-check visit. We conclude that some measures validated for indoor situations can already be used in pasture-based systems, while others need to be validated for their fitness for purpose and/or use in pasture conditions. Furthermore, thresholds should probably be determined for measures to fit with pasture contexts. If all measures can be made adaptable to all situations encountered on farms or variants of the measures can at least be proposed for each criterion, then it should be possible to produce a comprehensive welfare assessment protocol suitable for large-scale use in near future.

Animal performance and stress at weaning when dairy cows suckle their calves for short versus long daily durations.

Calves in most dairy farms are separated from their dams either immediately or within a few hours after birth, prompting increasing concern of the society for reasons of animal welfare. The aim of this study was to identify systems to maintain cow-calf contact (CCC) that balance the benefits for calf growth and health against the negative impacts on sellable milk and stress at weaning. We tested reuniting cows and calves for 20 min before (Before-group) or 2.5 h after (After-group) morning milking (in Trial 1) or for a 9 h period between the morning and evening milkings (Half-day-group, in Trial 2). In Control-groups, calves were separated from their dam at birth and fed with artificial nipple with tank milk provided daily at 13% (Trial 1) and 14% (Trial 2) of their BW. In both trials, each practice was applied on a group of 14 dam-calf pairs (7 Holstein [Ho] and 7 Montbéliarde [Mo]). All calves were weaned at a BW of at least 100 kg. In Trial 1, the After-group was prematurely stopped when the calves were eight weeks of age as calf growth became limited (340 g/d) due to low milk intakes (2.97 kg/d). During the first eight weeks of lactation, milk yield at the parlour was 29%, 51% and 42% lower in After-, Before- and Half-day-cows respectively compared to Controls. From week 14 to 16 when all calves were separated from their dam, Before-cows still produced 25% less milk than Control-cows while Half-day-cows reached the milk yield of Control-cows within a week. There were no significant differences in milk somatic cell count and in frequency of health disorders (cows and calves) between suckling and Control-groups. Compared to Control-calves, calf growth until weaning was higher in the suckling calves in Trial 1 (861 vs 699 g/d) and similar in Trial 2 (943 vs 929 g/d). At weaning, Before- and Half-day-calves started to vocalise earlier and continued to vocalise longer than Controls. In conclusion, the best compromise between cow milk yield and calf growth is a long period of CCC (9 h) between the morning and evening milkings. Still abrupt weaning stresses both cows and calves even if CCC has been restricted before separation.

Animal welfare official inspections: farmers and inspectors shared concerns.

Official inspections to check the compliance of farms with European legislation to protect farm animals are often perceived negatively by farmers. In addition, the inspections have a limited effect on improving farm compliance. We looked at the perceptions of both farmers and their inspectors about animal welfare and the inspections in a case study of dairy production in France. The identification of gaps and commonalities between both parties should help us to propose improvements in the inspection method by which inspections could more likely encourage compliance with animal welfare legislation. To achieve this aim, we conducted semi-structured interviews with 22 dairy farmers and their 19 inspectors. Both farmers and inspectors described animal welfare in terms of the state of the animal and of the living conditions and care provided to them. The majority of farmers found that the official checklist used by the inspectors is inappropriate to assess the welfare of their animals; inspectors themselves reported that they often use their own criteria and indicators (often based on the observation of animals) in addition to the official checklist. Both groups disagreed with some requirements of the legislation. These findings suggest that the content and background of the legislation to protect animals should be made clearer to both farmers and inspectors and that these two groups of actors should be involved in the definition of key points to be checked on farms, with special attention to animal-based indicators. All this could improve farmers' engagement with the results of the inspections and, hopefully, could lead to better compliance with legislation and improvements in animal welfare on farms.

Conditions for assessing cortisol in sheep: the total form in blood v. the free form in saliva.

Cortisol is often used as a stress indicator in animal behaviour research. Cortisol is commonly measured in plasma and can also be measured in saliva. Saliva contains only the free form of cortisol, which is biologically active, and saliva sampling is not invasive and may therefore be less stressful. Our study aims to guide the choice between the measurements of cortisol in plasma v. saliva depending on experimental conditions. We analysed the effect of the level of cortisol in plasma on the concentration of cortisol in saliva compared to plasma and the effect of saliva sampling v. jugular venepuncture on the cortisol response. In Experiment 1, blood and saliva were collected simultaneously under conditions in which the expected cortisol release in blood varied: in an undisturbed situation or after the isolation of lambs from their pens or the administration of exogenous ACTH (six animals per treatment). In Experiment 2, we subjected lambs to saliva sampling, venepuncture or neither of these for 8 days to evaluate how stressful the sampling method was and whether the animals habituated to it by comparing the responses between the first and last days (four animals per treatment). All animals were equipped with jugular catheters to allow regular blood sampling without disturbance. Samples were collected 15 min before any treatment was applied, then at various time points up to 135 min in Experiment 1 and 45 min in Experiment 2. In Experiment 1, we observed a strong correlation between salivary and plasma cortisol concentrations (r = 0.81, P < 0.001). The ratio between salivary and plasma cortisol concentrations was 0.106 on average. This ratio was higher and more variable when the cortisol concentration in plasma was below 55 nmol/l. In Experiment 2, venepuncture induced a larger cortisol response than saliva sampling or no intervention on day 1 (P < 0.02); this difference was not observed on day 8, suggesting that sheep habituated to venepuncture. We recommend the measurement of cortisol in saliva to avoid stressing animals. However, when the expected concentration in plasma is below 55 nmol/l, the cortisol in saliva will reflect only the free fraction of the cortisol, which may be a limitation if the focus of the experiment is on total cortisol. In addition, if cortisol is measured in plasma and blood is collected by venepuncture, we recommend that sheep be habituated to venepuncture, at least to the handling required for a venepuncture.

New recommendations for self-locking barriers to reduce skin injuries in dairy cows.

The design of self-locking barriers can affect cows' skin injuries and impair welfare. This study aimed to propose and refine recommendations, expressed relatively to the cows' dimensions, for self-locking barrier design to reduce risks for skin injuries on the neck/shoulder/back and on carpus of dairy cows. We recorded individual body dimensions and the dimensions of self-locking barriers (e.g. top rail height) and assessed skin injuries on 3801 cows from 131 loose-housing dairy farms. We explored the significant associations between presence/absence of skin injuries and self-locking barrier dimensions using weighted multivariable logistic regression, taking into account the diversity of feeding barriers within each farm. The robustness of the models was assessed by cross-validation. Cows had skin injuries mainly on the neck/shoulder/back (29.0%) and, to a lesser extent, on the carpus (14.0%). The final multivariable logistic regression models comprised 13 factors for skin injuries on the neck/shoulder/back, and 11 factors for skin injuries on the carpus. Skin injuries were significantly reduced when the self-locking barriers were inclined (neck/shoulder/back) and when the cows used a feeding table (i.e. flat) instead of a feeding manger or cribs (i.e. hollow) (carpus). A top rail height >1.05 × cow height (measured at withers) was significantly associated with fewer skin injuries on the neck/shoulder/back and on carpus. Skin injuries on the neck/shoulder/back and carpus were significantly reduced when the bottom rail was on the food side relative to the wall, and at a height <0.39 of cow height. Skin injuries were significantly less frequent when the separation wall had no sharp edges on the food side (neck/shoulder/back), was >0.4 of cow height (carpus), was thinner than 15 cm (neck/shoulder/back and carpus) and when the height of the feeding step was 0.04 to 0.1 of cow height (neck/shoulder/back) and the length of the feeding step was <0.2 of cow length (carpus). A headlock articulation nut positioned between 0.62 and 0.78 of cow height significantly reduced skin injuries on the neck/shoulder/back. Here, by combining the diversity of on-farm self-locking barriers and their respective dimensions, we were able to refine the International Commission of Agricultural and Biosystems Engineering recommendations for self-locking barrier design and to propose new ones. This information now needs to be confirmed on other datasets, but can already help farmers and dairy industry stakeholders improve the design of self-locking barriers to improve dairy cow welfare.

Relationships between welfare and reproductive performance in French dairy herds.

This study aimed to investigate the relationship between cow reproductive performance and welfare evaluated at the herd level using the Welfare Quality protocol. The 11 criteria, four principles (good feeding, good housing, good health and appropriate behavior, scale 0-100) and overall welfare category (excellent/enhanced/acceptable/not classified = poor welfare) were included as risk factors for calving to first service interval (CFSI) and calving rate (CR). The confounding factors cow breed, parity, season of calving and AI, calving to AI interval, rank of AI (1-3) and milk production were taken into account. The sample included 3951 AIs (2172 AI1, 1182 AI2, 597 AI3) in 124 French commercial dairy herds. Median CFSI was shorter for the cows bred in herds with a higher overall welfare category (median 75 and 76 days in enhanced and acceptable herds vs. 86 in poor welfare ones, P = 0.02). The scores for absence of injuries and expression of social behavior tended to be associated with CFSI (P < 0.10). Calving rate (34.5%) was not related to the overall welfare category. However, CR was positively related to the good housing score and a positive trend was observed with the scores for absence of prolonged hunger and absence of injuries. In conclusion, this study confirms a positive relationship between CFSI and welfare in dairy cows with no explicit links with specific aspects of animal welfare.

Stress and welfare: two complementary concepts that are intrinsically related to the animal's point of view.

The closely associated concepts of welfare and stress may be considered as opposites since welfare cannot be achieved under stress and vice versa. Stress was first considered as an unspecific response to any challenge taxing the organism's resources where the HPA axis plays a central role [Selye H. A syndrome produced by diverse nocuous agents. Nature 1936:32]. Along the same lines, welfare was considered as the state of an individual on a continuum between poor and good depending on the efforts required to adapt to the environment [Broom DM. Animal welfare: concepts and measurement. J Anim Sci 1991;69:4167-75]. However, these views cannot explain opposite results such as up- vs. down-regulation of the HPA axis and hypo- vs. hyper-behavioural reactivity under chronic stress. Later, it was shown that aversive situations trigger stress responses only if the individual perceives them as aversive. Mason [Mason JW. A re-evaluation of the concept of 'non-specificity' in stress theory. J Psychiatr Res 1971;8:323-33] suggested that the unspecificity of stress responses originates from a common emotion that produces them. Welfare has also been defined in terms of emotional states by Dawkins [Dawkins MS. Animal suffering, the science of animal welfare. London: Chapman and Hall Ltd.; 1980] and Duncan [Duncan IJH. Welfare is to do with what animals feel. J Agric Environ Ethics 1993;6:8-14]. Hence, both concepts are linked to mental states. Recent advances in psychology suggest that the very nature of an emotion results from a series of evaluations of the triggering situation that the individual makes based on criteria including novelty, predictability, controllability, and others [Scherer KR. Appraisal considered as a process of multi-level sequential checking. In: Scherer KR, Schorr A, Johnstone T, editors. Appraisal processes in emotion: theory, methods, research. New York: Oxford University Press; 2001. p. 92-120]. It is therefore suggested that the discrepancies found in the literature in terms of responses of the HPA axis or modification of behaviour under aversive conditions may stem from differences in the way a situation is evaluated. It is argued that stress comes from the animal's evaluation of the outcome of a situation, and that welfare is the state resulting from that evaluation.

Effect of autonomic blockers on heart period variability in calves: evaluation of the sympathovagal balance.

This study was designed to validate the measures of heart period variability for assessing of autonomic nervous system control in calves. Eight calves received an injection of either 0.5 mg/kg atenolol (sympathetic tone blockade), 0.2 mg/kg atropine sulfate (parasympathetic tone blockade), 0.5 mg/kg atenolol + 0.2 mg/kg atropine sulfate (double autonomic blockade) or saline. In the time-domain, we calculated the mean instantaneous heart rate (HR), mean of RR intervals (MeanRR), standard deviation of RR intervals (SDRR) and that of the difference between adjacent intervals (RMSSD). In the frequency-domain, the power of the spectral band 0-1 Hz (TPW), the power of the 0-0.15 Hz band (LF), that of the 0.15-1 Hz band (HF), and the LF/HF ratio were considered. The net vago-sympathetic effect (VSE) was calculated as the ratio of MeanRR in a defined situation to MeanRR during the double blockade. Atenolol injection had no effect on cardiac activity, whereas atropine induced large modifications which were moderated when atenolol was administered at the same time. VSE, HR, MeanRR and RMSSD were found to be valid indicators of the parasympathetic tone of calves because of large variations due to the drug and low individual variations. No measure reflected the sympathetic tone.

Learning to suckle from an artificial teat within groups of lambs: Influence of a knowledgeable partner.

This work was aimed at finding evidence of observational learning in sheep. The task to be learned was that of suckling milk from a bucket provided with teats. Lambs were reared in groups of either four neonates and an older lamb accustomed to artificial suckling (14 experimental lambs) or five neonates (16 controls). One-hour observations were made five times a day. The lambs that learned were grouped and observed for three hours once a week. All experimental lambs learned within three days as compared to nine for the 16 controls. Experimental lambs moved and sniffed or sucked the bucket more often than the controls (2.0 ± 1.5 vs. 1.5 ± 1.0% time spent moving, 7.1 ± 6.2 vs. 1.6 ± 1.8 sniffing/hour, 3.7 ± 3.6 vs. 1.7 ± 1.7% time spent sucking, P < 0.05). The time to first suckling was not related to these measurements, neither was it related to other behavioural traits. Learning to suckle from the teat-bucket may be a socially transmitted phenomenon, and not only by enhancement of investigation.

Decrease in cow-calf attachment after weaning.

Experiments were undertaken to measure attraction of suckler calves to their dams after separation for abrupt weaning. On days 0, 2, 7 and 20 after weaning in experiment 1 and on days 1, 9, 16, 24 and 35 after weaning in experiment 2, calves were observed in a pen where they could stay either near the dam or near another familiar cow or calf. On days 0, 2, 7, 20 and 35, calves and their dams were reunited for 2 min. Calves showed a preference for the dam to another cow up to day 24 and to a calf up to day 9 only. From day 20, cows rejected their calves at suckling. It is concluded that the calves remained attracted by their dams for at least three weeks after weaning while the cows already rejected them. In addition, attraction between calves increased after weaning.

Providing social contacts and objects for nibbling moderates reactivity and oral behaviors in veal calves.

The aim of this work was to assess the role of social and physical enrichment in the adaptation of veal calves to their environment. We compared calves housed in individual stalls that varied in the extent of contacts they allowed between neighbors (16 calves: open partitions; 16 calves: solid partitions; 32 calves: solid and extended partitions preventing all contact). All but 16 out of the 32 isolated calves were provided with a piece of tire and a chain, objects they could easily nibble. We assessed time budget, behavioral reactions to a water throw, neuroendocrine responses to stress (ACTH challenge and catecholamine synthesis), health, and growth. Calves kept in isolation displayed more startled reactions (16 isolated calves vs 5 non-isolated calves were startled by the throw, P < .05). Calves without objects spent more time nibbling at the feeding grille (5 vs 3% time, P < .01), licking their lips and tongue-rolling (7 vs 4% time, P < .05). Social contacts and the provision of objects had no incidence on neuroendocrine measurements and growth. Contacts with neighbors resulted in a slight but nonsignificant rise in disease. Depriving calves of social contacts increases behavioral reactivity, probably because there are no peer animals through which reactions can be moderated, and the lack of adequate objects to nibble promotes self-directed activities.

The influence of farmers' behavior on calves' reactions to transport and quality of veal meat.

The relationships between farmers' behavior toward veal calves, calves' responses to handling and transport, and veal meat quality were assessed. Two groups of 10 veal units were selected based on previous observed farmers' behavior toward the calves: one group consisted of farmers who had shown predominantly "positive" behavior toward the calves, and the other group of farmers had shown predominantly "negative" behavior. Calves were observed for their reactions to people at the unit, and 20 calves per veal unit were transported either directly to the slaughterhouse or subjected to additional transport consisting of a supplementary 20-min transport with additional unloading and loading. The effort needed to load the calves onto the truck and their behavior during loading was observed. During loading and unloading, and during lairage at the slaughterhouse, potentially traumatic incidents (falling down, hits against structures, slips) were recorded, and heart rate and cortisol measurements were taken. Carcasses were evaluated on their weight, color, conformation, pH, and bruise level. A meat sample was taken from the longissimus thoracis muscle for physical, chemical, and sensory analysis. Calves originating from "positive behavior" units showed fewer fear responses to people at the veal unit, needed less effort to be loaded to the truck, had lower heart rates during loading and unloading, and had fewer incidents at the slaughterhouse than calves from "negative behavior" units (P < 0.05). Carcasses from calves from "positive behavior" units were paler, and analyses of the meat sample revealed lower pH, moisture level, and redness compared to carcasses from calves from "negative behavior" units (P < 0.05). Additional transport led to a lower cortisol level after transport and to higher carcass pH values at slaughter compared to direct transport (P < 0.05) but did not affect meat quality. We concluded that farmers' positive behavior toward veal calves during rearing is likely to reduce the emotional responses of calves to handling and transport and to lead to fewer incidents, compared to negative behavior. This reduction of calves' emotional responses seems to be the reason for improved veal meat color.

Adrenocorticotropic hormone and cortisol in calves after corticotropin-releasing hormone.

The aim for this study was to analyze responsiveness of the hypothalamo-pituitary-adrenocortical axis to exogenous bovine corticotropin-releasing hormone (bCRH) in calves. Two dose-response studies were carried out, using either bCRH alone (dose rates of 0, .01, .03, and .1 microg bCRH/kg live weight) or in combination with arginine-vasopressin (bCRH:AVP, 0:0, .1:.05, .5:.25, and 1:.5 microg kg live weight). The bCRH was administered i.v. to calves (n = 5 to 7 per dose) housed individually or in groups. Serial blood samples were obtained from before to 300 min after injection and analyzed for plasma ACTH and cortisol concentrations. The lowest bCRH dose that produced a response in all calves was .1 microg/kg. In the experiment using bCRH with AVP, increasing the bCRH dose from .1 to 1 microg/kg resulted in an increase in peak ACTH concentration (321 vs. 2,003 pg/mL) but did not significantly affect the peak cortisol concentration (37 vs. 40 ng/mL). The time to reach the peak cortisol concentration increased with the dose of bCRH with AVP (from 38 to 111 min). The ACTH and cortisol concentrations determined at any time between 20 and 90 min after bCRH injection were correlated to the integrated responses calculated as areas under the ACTH and the cortisol curves (r between .61 and .99, P<.05). In comparison with results from studies in humans, pigs, and sheep, our data showed that the pituitary of calves seems less sensitive to CRH than that of other mammals, despite a greater capacity to produce ACTH. Moreover, the calf's adrenals seem to have a lower capacity to produce cortisol than adrenals of other mammals. As in other species, it seems that AVP enhances the release of ACTH and cortisol. For CRH challenge to be used in calves, we suggest injecting at least .1 microg of bCRH/kg live weight either with or without AVP and taking several blood samples before injection and between 20 and 90 min after injection.

Reducing veal calves' reactivity to people by providing additional human contact.

We studied the importance of the stockperson's behavior on veal calf behavior using 22 veal calves housed in individual crates. Eleven calves received minimal contact from the stockperson, and the other 11 calves were stroked and allowed to suck the stockperson's fingers after each meal during the entire fattening period (21 wk). The effects of this additional contact with the stockperson on the calves' responses to people was studied, when in their home environment (crate) or outside their home environment (singly in a novel arena). When tested in their home environment, the calves receiving additional contact withdrew less from the approach of humans (familiar or unfamiliar) (P < .05) compared with control calves. When tested outside the home environment with a human (familiar or unfamiliar) standing motionless, calves that had received additional contact interacted more frequently and for a longer time with the humans and defecated less often compared with control calves (P < .05). In conclusion, being stroked and sucking the stockperson's fingers seemed to be experienced as positive by the calf, because they reduced withdrawal from and increased approaches to familiar and unfamiliar humans in familiar and unfamiliar environments. Such a lower reactivity to people could improve ease of handling, animal performance, and animal welfare.

The impact of gentle contacts on ease of handling, welfare, and growth of calves and on quality of veal meat.

It has been demonstrated previously that regularly stroking and letting calves suck fingers leads to less avoidance and more approach behavior of the calves toward people. To examine whether these positive contacts affect the welfare and productivity of calves and the quality of veal meat we used 22 veal calves housed in individual crates. Half of them received minimal contact with the stockperson (controls), and the other half were given additional gentle contacts around meals, by stroking the calves and allowing them to suck the stockperson's fingers, during the entire fattening period (21 wk). Welfare was assessed through behavioral reactivity (reactions to handling, to surprise stimuli, and to novelty), neuroendocrine responses to stress (cortisol in response to an ACTH challenge, catecholamine-synthesizing enzymes), and health (number of medical treatments, abomasal lesions). Calf productivity was assessed through growth rates and meat quality through glycolytic potential (an estimator of resting glycogen level in muscle), pH, and color. Calves that received gentle contacts were less agitated (P < .01) and tended to defecate less (P = .08) when handled in a cart on wheels than the control calves, but no treatment effects were found in reactivity to novelty and surprise stimuli, responses to ACTH, and catecholamine synthetic potential. Calves given gentle contacts had fewer abomasal lesions than controls (0/11 vs 4/11, P = .05). The glycolytic potential of the semimembranosus muscle was higher in calves that received gentle contacts than in controls (172.6 vs 154.1 micromol/g, P < .05), but no treatment effects were observed on meat pH, meat color, or growth rates. It is concluded that gentling veal calves reduces their reactions to handling. Gentle contacts reduce the reaction to transport shown by differences in glycolytic potential. In addition, the reduction in reactions to handling and the decreased incidence of abomasal lesions can contribute to an improvement of the calves' welfare.