Christian C. Krohn

Play behaviour in dairy calves kept in pens: the effect of social contact and space allowance

Abstract The effects of social contact and space allowance on the expression of play behaviour in domestic calves were studied. Forty-eight female dairy calves in three groups were housed in one of four pen types: (1) small single pen (0.9 m×1.5 m); (2) large single pen (1.8 m×3.0 m); (3) small group pen (1.8 m×3.0 m for 4 calves); and (4) large group pen (3.0 m×5.4 m for 4 calves). The behaviour of all calves was video-recorded for 8 h in week 2 and for 24 h in weeks 4 and 6 of the experiment. Data for play behaviour were obtained from each individual for all hours of observation. In weeks 4 and 6, space allowance affected the quantity of locomotor play. A low space allowance reduced locomotor play in both individually and group-reared calves. The quality of locomotor play was also affected. Elements of locomotor play that involve much movement were either absent or rarely seen in the small single pens. Furthermore, calves in single pens were less active than calves in group pens. The results of this study indicate that sufficient space is essential for the expression of play behaviour in domestic calves. It is suggested that play behaviour may be used to indicate the presence of good welfare in calves and in juveniles of other farm animal species. The use of a measure to indicate the presence of good welfare in addition to measures to indicate the absence of poor welfare may be a step towards a better assessment of welfare in farm animals.

Effect of single versus group housing and space allowance on responses of calves during open-field tests

Abstract 32 dairy heifer calves were housed in one of four pen types: (1) a small single pen (0.9 m × 1.5 m); (2) a large single pen (1.8 m × 3.0 m); (3) a small group-pen (1.8 m × 3.0 m for four calves); and (4) a large group-pen (3.0 m × 5.4 m for four calves) until three months of age. Thereafter, all calves were housed individually in tether stalls which were 0.9m wide. Each calf was subjected to two test-sessions: one before tethering at three months of age and one at six months of age. Each test session included two tests. The first test was an open-field test with an unfamiliar calf present and the second was an open-field test in an empty arena. Behaviour and heart rate were recorded. Based on the data for the open-field test with an unfamiliar calf present, two principal components reflecting exploratory motivation and fear of unfamiliar calves, respectively, were defined. At three months of age, individually reared calves had higher scores for the principal component reflecting fear of unfamiliar calves. Principal components reflecting exploratory motivation and fear, respectively, were also defined based on data for the open-field test in an empty arena. At three months of age, individually reared calves had higher scores for the principal component reflecting fear in this test. The results suggest that individually reared calves are more fearful when introduced to a novel social situation and when isolated in a novel arena. Differences in space allowance did not affect the measured responses during the tests at three months of age. At six months of age, no effects of either social rearing or space were found.

Behaviour of dairy cows kept in extensive (loose housing/pasture) or intensive (tie stall) environments I. Experimental procedure, facilities, time budgets - diurnal and seasonal conditions

Abstract Twelve dairy cows were placed in a stimuli-rich environment, a ‘dairy cow park’, for 2.5 years. The ‘park’ consisted of an extensive barn with deep bedding, a yard and a pasture. The cows were milked and fed twice a day in the barn, but had free access to the whole area at all times. During the experiment the cows were observed 2–6 days month−1, and their preference for being indoors or outdoors, for standing or lying, eating mixed rations or grass, their daily walking distance and synchronization of lying behaviour, were recorded. During summer the cows spent 17.2 h outdoors each day, mostly at pasture; in winter they only spent 4.8 h outdoors each day. With the exception of frosty days, the cows frequently spent 1–3 h outdoors on winter nights. On frosty days they remained indoors all day. The cows lay indoors on deep bedding only in winter, while in summer they mainly preferred to lie out on pasture. During winter the cows ate mixed rations for 2.2 h and grass for about 0.7 h day−1, and during summer, 1.3 h and 4 h, respectively. Time spent eating mixed rations was not correlated with rank order. The lying behaviour was more synchronized at pasture than in the tie stall. The synchronization on deep bedding was intermediate. During summer, the cows walked 2.5 km (SD 0.6 km) daily and spent most of the nights at pasture. The daily walking distance was 0.8 km (SD 0.6 km) during winter. Except for frosty days when cows remained indoors, the weather within a month had no significant effect on the walking distance.

EFFECTS OF HOUSING IN DIFFERENT SOCIAL ENVIRONMENTS ON OPEN-FIELD AND SOCIAL RESPONSES OF FEMALE DAIRY CALVES

To investigate the effect of social contact during early development on open-field responses and social responses, 80 female dairy calves were housed either in open single pens (SOpen), closed single pens (SClosed), calf-groups (GCalf), or groups of calves and cows (GCow) until 3 months of age. During the first 3 months, the calves were open-field tested at 2 and 10 weeks of age. Calves isolated in closed single pens (SClosed) performed more exploration during the open-field tests at 2 and 10 weeks of age than did calves housed in open single pens (SOpen). During the open-field test after the experimental period at 6 months of age, previously isolated calves (SClosed) had a longer latency to enter an open-field arena, and during a social test at this stage group-reared calves (GCalf and GCow) sniffed and mounted other calves more than calves housed in single pens (SOpen and SClosed). The results suggest that isolation increases the motivation to explore a novel environment, and that housing in groups faci...

Resting and social behaviour of dairy heifers housed in slatted floor pens with different sized bedded lying areas

Abstract The hypothesis that an increase in the straw bedded resting area for group housed heifers would increase synchronization of resting behaviour and decrease aggressive and abnormal behaviour was tested. An experiment was conducted on two Danish commercial dairy farms with 20 Danish Friesian heifers (approximately 400 kg) from November 1994 to April 1995. The experimental pens were constructed on existing slatted floor and contained a total area of 27 m 2 per pen with five heifers in each pen. Three different sizes of lying area (1.8, 2.7 and 3.6 m 2 per heifer) bedded with straw were established in each pen for three consecutive periods of 5 weeks. Resting and social behaviour were recorded using direct observations for 24 h at the end of each 5 week treatment period. The synchronization of resting behaviour was reduced ( P = 0.002) when the heifers were offered 1.8 m 2 bedded lying area per heifer compared with 2.7 or 3.6 m 2 per heifer, and the heifers were more aggressive, as more butting ( P = 0.007) and forcing another heifer to stand up ( P = 0.02) were seen. The frequency of leaning against other heifers was highest ( P = 0.05) at the lowest space allowance in the bedded area. The results indicate that increasing the resting area from 1.8 m 2 to 2.7 or 3.6 m 2 per heifer improved the welfare of group housed dairy heifers.

Association between resting behaviour and live weight gain in dairy heifers housed in pens with different space allowance and floor type

The hypothesis that daily gain is associated with resting behaviour in heifers is tested in this paper. The test is based on two experiments conducted on Danish commercial dairy farms with Danish Friesian heifers (300–400 kg) in the winter periods. Group size was 5–6 heifers per pen. Experiment A, with 80 heifers, investigated the effect of different space allowances (1.5 or 3.0 m2 per heifer on fully slatted floor) and different floor types (fully slatted or with access to bedding). Experiment B, with 70 heifers, investigated the effect of space allowance in the deep bedding area (1.8; 2.7 and 3.6 m2 resting area per heifer). Data from experiment A showed a tendency towards a positive correlation between lying periods and daily gain for heifers housed on fully slatted floor but not when housed with access to bedding. There tended to be a positive correlation between number of lying periods and daily gain at a low but not at a high space allowance. The data from experiment B showed a tendency towards a positive correlation between lying time and daily gain at a low space allowance in the deep bedding area and not at a high space allowance. Among heifers in the pens with access to bedding in experiment A, it was found that one particular heifer in each of the four pens lay significantly more on the slatted floor and this heifer had an average daily gain which was less than the others.

Effect of space allowance in deep bedding systems on resting behaviour, production, and health of dairy heifers

An experiment was conducted on three Danish commercial dairy farms using 70 Danish Friesian heifers over a period of 141 to 162 days beginning in November. Average body weight of the heifers was 315 kg at the beginning of the experiment. Fourteen experimental pens were established with a flock size of five and different space allowance in the deep bedding area: 1.8, 2.7, and 3.6 m2 resting area per heifer. The total space allowance inclusive of an unstrawed area at the feed manger was 3.6, 4.5, or 5.5 m2 per heifer in herd 1, 3.6 or 4.5 m2 per heifer in herd 3, and 3.0 or 4.9 m2 per heifer in herd 2. Eating space was standardized within pens to 60 cm per animal. Feed was available ad libitum. At 1.8 m2 resting area per heifer, the heifers were unable to synchronize their resting behaviour, and the variance of the daily lying time was higher compared with heifers at 2.7 or 3.6 m2 resting area. None of the heifers were lying on the unstrawed area. Total lying time was not affected by the space allowance of ...

Effect of Space Allowance, Access to Bedding, and Flock Size in Slatted Floor Systems on the Production and Health of Dairy Heifers

Abstract An experiment was conducted on seven Danish commercial dairy farms with 200 Danish Friesian heifers (315 kg) in 152 days from the month of November. Founded on existing slatted floor systems, 32 experimental pens were established with Low (L) or High (H) space allowance (1.5 vs. 3.0 m2 per animal), different type of separate lying area (Slatted (S) vs. Bedded (B) floor) and different flock size (6 vs. 12 animals). Eating spaces were standardized to about 50 cm per animal. Ad libitum feeding was practised and rations contained a maximum 30% concentrates (dry matter). An increase in space allowance from 1.5 to 3.0 m2 per animal in pens with fully slatted floors increased the live weight gain by 174 g day−1 or 31% (P = .04) and net energy intake per kg live weight gain was reduced by 23% (P = .04). Heifers housed in small pens lay down less than heifers in large pens. Access to bedding affected number of lying periods. Production, however, was not influenced by access to a bedded lying area. Flock s...

Long-term Effect of Housing Method during the First Three Months of Life on Human-Animal Relationship in Female Dairy Cattle

The effect of housing during the first three months of life till the end of the first lactation on the human-animal relationship and milk production was examined in an experiment with four treatments of 20 female dairy calves each. For the first 12 weeks of their lives, the calves were housed in either open single pens (SOpen) or closed single pens (SClosed), in groups of five calves (GCalf) or in groups of five cows and calves (GCow). Calves housed in a closed single pen approached humans more than calves housed in an open single pen. There was no difference in the ease of handling. The human-animal relationship was not affected by type of housing. Calves housed in groups of calves and cows sought less human contact, but were not difficult to handle. Milk production was not affected by housing method during early rearing. Therefore, group housing, which allows full socialization with other animals and involves better welfare than individual housing, can be recommended, as no negative effect was found on ...