Abstract: The mechanisms of activity synchronization in group living ungulates are not well understood. In a case study on herd of 15 Gasconne beef cows with calves observed during a total of 25 summer daylight periods in 2004 and 2005, we examined whether cows similar to each other in body weight or in reproductive status were more synchronized and whether the timing of activity switches were determined by specific leading animals. We calculated the synchronization of all possible pairs of cows in the herd and tested the effects of similarity in body weight and in reproductive status (lactating versus non-lactating) on synchronization in the pair. Further, we assessed whether any specific individuals, and especially the dominant cows, were more able, through their own activity switch, to incite another cow to follow shortly with her switch in activity. We found that body weight differences had a negative influence on pair synchronization (GLMM, F1,65 = 6.79; p < 0.05), but reproductive status did not affect the synchronization. Cows' individual identity explained only a small proportion (<2%) of variability in intervals between switches of subsequent cows. Furthermore, dominance status of an individual cow did not correlate with mean interval between her activity switches and activity switches of the next cow (lying down: Spearman correlation, rs = -0.16, n = 14, p > 0.10; standing up: Spearman correlation, rs = -0.38, n = 14, p > 0.10), indicating that there were no leading animals initiating switches in activity in our herd.

Abstract: Abstract Habituated horses have been found to have a calming effect on conspecifics in fear-eliciting situations. In practice, experienced horses are often used as companions when young horses are introduced to potentially frightening situations, like loading onto a trailer. However, studies of social transmission of habituation in horses are scarce. This study investigated if demonstration by a habituated demonstrator horse influenced the willingness of young Icelandic horses (n = 22, 3 years old) to cross a novel surface. Observer horses (n = 11) were allowed to observe the similarly aged demonstrator horse being led five times across a novel surface. Immediately afterwards the observer horses were given the opportunity to cross the novel surface themselves to obtain food on the other side. Controls (n = 11) were allowed to observe the demonstrator eating on the opposite side of the novel surface but not the demonstration of crossing the novel surface. All observers and controls succeeded the task, but observers had significantly lower average and maximum heart rate, compared to controls. This result suggests a calming effect of the demonstration, which could be exploited for habituation training of horses in fear-eliciting situations.

Abstract: We examined whether very young dairy calves are able to discriminate between two people, and whether they use the colour of clothing or other indices to do so. During the familiarisation phase, one person (the familiar rewarder), who always wore the same colour clothes, gave milk, spoke gently and patted the calves in their individual pen for 6 days each week. During the test phase, the calf had to make a choice in an Y-maze placed in front of the gate of its stall. When the calves chose the familiar rewarder, they received 200 ml of milk as reinforcement. When they made the incorrect choice, they received nothing and were returned to their stall. On each test day, the calves made eight choices. The criterion of success was that the calf made at least six correct choices in eight trials on each of two consecutive test days (P<0.021 by the binomial law). The first experiment was carried out with fourteen 1-week-old male and female Holstein calves to see if calves could approach a person, who changed position in the maze, in order to obtain a feed reward. The familiar rewarder wore the same clothes as during the period of familiarisation and was in one arm of the Y-maze. The other arm was empty and the position of the familiar rewarder in the maze was randomised. Eleven of the 14 calves reached the criterion for success, after only three tests. The second experiment, carried out with five 2-week-old calves, examined whether the calves can differentiate the familiar rewarder (wearing the same clothing as during the period of familiarisation) from another person (the non-rewarder) wearing clothes of a different colour. The criterion of success was reached by all five calves. The third experiment was carried out with seven 2-week-old calves. It examined whether the calves can differentiate the familiar rewarder and the non-rewarder, when the two people are wearing clothes of the same colour (i.e. the same colour worn by the familiar rewarder during the phase of familiarisation). None of the calves were able to reach the criterion of success within a limited number of four test days. Often, calves would always choose the same arm of the maze. The fourth experiment was carried out on six 1-month-old calves. It was similar to experiment 3 with the difference that the familiar rewarder and the non-rewarder both wore the same colour clothes, but which were not the same colour as worn during the phase of familiarisation. Only one calf achieved the criterion of success within two test days. Results demonstrated that colour cues help very young calves to discriminate between two people, when these people wear different colour clothing. Some calves may be able to use other indicators than the colour of clothing. The Y-maze method is an promising way of examining calves' abilities to recognise people.

Abstract: The human-animal relationship is an important factor when considering animal welfare at herd level. In the present study, two behavioural tests for the on-farm assessment of the human-animal relationship at herd level of dairy cows housed in loose housing cubicle systems were evaluated with respect to inter-observer reliability, test-retest reliability, effect of familiarity of test person as well as inter-correlation of the two tests. In a voluntary animal approach (VAA) test, the number of cows and the latencies to approach and touch a stationary test person was measured. In an avoidance (AV) test, the cows' avoidance reactions to an approaching test person were categorised. A first study was carried out in 12 commercial Danish and Austrian dairy farms. On each farm, both behaviour tests were carried out on the same day and repeated within 4-5 days. For each test, cows were tested by both an unfamiliar and a familiar test person (the stock-person) and two observers simultaneously registered the animals' test responses. The inter-observer reliability of both behavioural tests was found to be high (VAA: 2.5-m approach r=0.98 (P<0.001) and touch r=0.97 (P<0.001); AV: Kappa coefficientweighted=0.886 (prevalence index for flight distance>=2 m is 0.636)). The cows at herd level showed shortest latency for touching an unfamiliar test person on the first test day (P=0.006). Further, the AV test had a high test-retest reliability (Kappa coefficientweighted=0.503 (prevalence index for flight distance>=2 m is -0.660)) and results indicated no effect of familiarity of test person (Kappa coefficientweighted=0.463 (prevalence index for flight distance>=2 m is -0.677)). In a second study, the correlation between the two behavioural tests (similar measures) was evaluated. On each of 10 commercial Danish dairy farms with loose housing cubicle systems at four repeated sessions, both behaviour tests were carried out on the same day. For each test cows were tested by the stock-person. The VAA and AV tests at herd level were highly correlated (rs=-0.84; P=0.002). The results suggest that the AV test is valid and applicable for on-farm assessment of the human-animal relationship at herd level. This accounts only partly for the VAA test, which seem to be more unclear regarding motivation for the animals' approach behaviour.

Abstract: Abstract Social learning is the capacity of animals to acquire adaptive information from others. In the case of fear responses, animals can learn fearful or non-fearful responses by observing the behavior of conspecifics. Tonic immobility (TI) is an anti-predatory behavior elicited during intense fear situations. Studies have revealed that regular contact with humans can reduce TI responses in animals. In our study, we evaluated the effect of human contact on the TI responses in guinea pigs. We also evaluated the effect of cohabitation (non-fearful animals with fearful animals) on their TI responses. To achieve this, we measured the TI responses induced by postural inversion and restraint in guinea pigs as a result of different treatments. In our first experiment, we determined the effect of human contact on TI responses by establishing 3 treatment groups: no contact, handled, and habituated. In our second experiment, we addressed the effect of social learning on TI response by testing TI response in habituated, and unhabituated animals that had cohabitated for 10 days. In the first experiment, 10 days of either handling or habituation did not prevent TI in guinea pigs, but habituation did increase latency [F(2,119) = 14.19; p < 0.0001] and handling or habituation decrease duration [F(2,119) = 15.01; p < 0.0001] of the TI behavior in the guinea pigs. In the second experiment, the cohabitation of unhabituated and habituated animals reduced TI duration [F(2,93) = 5.058; p < 0.008]. These data suggest that both forms of human interaction can reduce experimenter fear in guinea pigs. It therefore seems that unhabituated guinea pigs learn not to fear the experimenter by cohabitating with habituated guinea pigs.