An important factor in obtaining high levels of pregnancy in dairy cows is to accurately detect estrous in order to inseminate at the optimal time. The present study installed in a freestall barn an estrous detection system for dairy cows that utilizes pedometer reading antennas (e.g., in the cross alleys) that read the number of steps when cows walk passed them. The system can read the pedometer data produced by voluntary cow movement. Data from all 47 cows housed in our old freestall barn were analyzed in the study. An increase in pedometer readings occurred in 44 cows, of which 41 showed normal estrous cycle. During non-estrous, all additional integration of pedometer readings showed changes in a straight line, while during estrous a dramatic increase in pedometer readings occurred. Further, the average number of steps during non-estrous was 5.2 counts per hour, but was increased during estrous, to 23.0 counts per hour. Cows were about 4.4 times as active during estrous as they were during non-estrous. The duration of increased walking activity occurs for approximately 12.7 hours on average, and standing and/or mounting behavior was observed during this period. Ovulation was defined as occurring 28.5 hours after the start of increased walking activity. Using the multiple pedometer reading system, the start time of increased walking activity could be clearly determined, and the optimum time for artificial insemination was defined as between 4 and 24 hours after this time. Further, while there is no diurnal rhythm in the number of steps per hour, there is a clear threshold level easily separating the number of steps in estrous and non-estrous. Testing of this estrous detection system in our robot milking freestall barn showed very high system efficiency for estrous detection at 91.4%, and very high system accuracy at 83.5%.

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In order to define the stress response and negative energy balance in the metabolic changes of transition dairy cows just after parturition, the plasma concentration of cortisol, glucose, noradrenaline (NA) and free fatty acid (FFA) were measured. Blood samples were collected from the coccygeal artery on the 14th day before parturition (-14D), the day of parturition (+1D), and the 5th (+5D), 10th (+10D), 20th (+20D) and 30th days (+30D) after parturition. The plasma concentration of cortisol was analyzed using the HPLC-UV system, and the plasma concentration of NA was analyzed using the HPLC-ECD system. The plasma concentration of cortisol and glucose increased significantly (P<0.05, P<0.05) on +1D. The plasma concentration of NA and FFA also increased (P<0.05, P<0.05) on +1D and remained at a slightly high level until +10D. Covariance analysis between cortisol and glucose showed a significant difference (P<0.05) on +1D. This suggests a stress response caused by parturition. Covariance analysis between NA and FFA showed a significant difference (P<0.05) on +1D, and on +5D and +10D. The different distribution on +1D suggests a stress response caused by parturition. The different distribution on +5D and +10D suggests FFA mobilization caused by the lack of energy for milk production. These results indicated an apparent stress response on +1D and this was followed by a negative energy balance in the transition daily cow.

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We investigated the behavioural and physiological responses of sika deer (Cervus nippon) to wolf's (Canis lupus) dry faeces from the viewpoint for the control of deer feeding on agricultural and forestry products. In experiments 1 and 2, the feeding behaviour of sika deer (n=27) in four troughs provisioned either with bottles containing wolf's faeces (Wf), domestic cats' faeces (Cf) or cattle urine collected immediately after slaughter (Cu), or with an empty bottle as a control, was investigated for 10 min. The troughs, each containing 1kg fresh weight of hay cube, were randomly allocated. During the first four trials in experiment 1, 60, 40 and 200g of Wf, Cf and Cu, respectively were used. The mean amounts of hay cube eaten among the four troughs differed significantly from the expected amounts (P<0.01, Wf: 20g, Cf: 240g, Cu: 95g, Control: 520g). Furthermore, only Wf induced frightened behaviour in deer after smelling of the trough or bottle. In the four trials of experiment 2, we investigated whether the suppressive effect of Wf on the feeding behaviour of deer depends on the amount of faeces. During the first two trials, 5, 10 and 60g of Wf were used. During the last two trials, 1g of Wf and empty bottles previously containing 10 or 60g of Wf just before the trials (Empty10 and Empty60, respectively) were used. The mean amounts of hay cube eaten among the four troughs differed significantly from the expected amounts (P<0.01, Wf60: 0g, Wf10: 0g, Wf5: 0g, Control: 1000g; P<0.01, Wfl: 30g, Empty60: 140g, Empty10: 120g, Control: 715g). In experiment 3, we investigated the physiological response of female deer (n=5) by placing a bottle containing Wf (60g) or water near their noses for 1 min. The mean heart rate after the presentation of the Wf-containing bottle was greater than that after the presentation of the water-containing bottle (92.7vs. 84.4, P=0.07). Further, the concentration of salivary chromogranin A at 15 min after the presentation of the Wf-containing bottle was greater than that under control conditions (P=0.08). These results suggest that Wf suppressed the feeding behaviour, induced an aversive behavioural response and stimulated the sympathetic nervous system in sika deer.

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The objective of this study was to determine the change in ration shape during cow feeding in a free-stall barn. A new device was made to measure the height of the ration without contact. The experiment started at 13:00 with pushing up the ration in a free-stall barn and ended at 17:00. The height of the ration was measured at 10cm intervals from trough wall to 150cm away (15 points) in parallel lines at 2m intervals (6 lines) on a flat-type trough. The length from the trough wall to the edge of the ration and to the top of the ration at the end of the experiment (17:00) were significantly (P<0.05) greater than those at the start of experiment (13:00). The height of the top of the ration did not differ from the start to the end of the experiment. The height of ration at the end of the experiment had significantly (P<0.05) decreased at 10-50cm, and increased at 90-140cm from the trough wall. The decrease in the height of the ration in the 10-40cm positions and increase in 90-120cm positions occurred linearly with time after the start of the experiment. There was no change in the height at 70cm from the trough wall. The changes in ration height at several distances from the trough wall were successfully quantified.

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We investigated the influence of shearing and a change in appearance on the frequency of agonistic behaviour among sheep flocks. Two groups of 7 Suffolk sheep were studied. Flock A consisted of 7 ewes (4.9±1.9 years old) and Flock B consisted of 4 ewes and 3 wethers (4.4±1.8 years old). As a pre-experiment to confirm the stability in each flock, agonistic behaviour (fighting, head butting, charging, head throw, threat, escape and avoidance) was recorded continuously for 2 hours every day for 4 successive days. Each flock was observed for 2 hours before, immediately, 1 day after and 1.5 months after shearing. At first, sheep in each flock were tethered individually for 4 hours. They were then released simultaneously, and were observed continuously for 2 hours (before shearing), and their agonistic behaviour was recorded. After these observations, all except two sheep from each group were sheared. The sheared and non-sheared sheep were treated as before, and the agonistic behaviour in the flock was observed for 2 hours immediately after being reunited, after 1 day and after 1.5 months. In the pre-experiment, the observed agonistic behaviour of each flock was found to be of the non-physical type, and each flock was considered socially stable. During the experiments, a significant increase in the frequency of agonistic behaviour in each flock was observed immediately after shearing compared with that before shearing (P<0.01). The frequency of agonistic behaviour 1 day after shearing in Flock A was the same as that before; whereas the frequency of agonistic behaviour 1 day after shearing in Flock B was less than that observed immediately after shearing (P<0.01), although it was still more than that observed before shearing (P<0.01). These results indicate that shearing can affect and lead to discrimination in the same flock over a short period of time.

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