Provision of additional walls in the resting area – the effects on
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resting behaviour and social interactions in goats
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Applied Animal Behaviour Science 122, 35-40
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Provision of additional walls in the resting area – the effects
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on resting behaviour and social interactions in goats
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REBECCA EHRLENBRUCH, GRETE HELEN MEISFJORD JØRGENSEN, 4
INGER LISE ANDERSEN AND KNUT EGIL BØE 5
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Norwegian University of Life Sciences, Department of Animal and Aquacultural 7
Sciences, P.O. Box 5003, 1432 Ås, Norway 8
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Corresponding author: Rebecca Ehrlenbruch, (e-mail: [email protected] 10
telephone: +47 64965202; fax: +47 64965101) 11
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Abstract
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The aim of this study was to investigate the effects of providing extra walls, in 15
addition to the already existing pen walls, in the resting area on resting behaviour and 16
social interactions in goats. Twenty-four dehorned dairy goats (seven weeks pregnant) 17
were distributed into six groups with four goats in each group. The groups were 18
systematically rotated between six pens; five experimental pens with additional walls 19
and one control. The experimental pens were equipped with wooden walls with the 20
following configurations: parallel wall (PAR), cross walls (CRO), perpendicular wall 21
(PER), cubicles (CUB) and three walls (THR). Each pen had a total area of 1.5 22
m2/goat with a separate activity and resting area of equal size (0.75 m2/goat). For 23
each treatment the goats were given three days to get accustomed to the treatments 24
before they were video recorded for 24 hours. Resting behaviour and general activity 1
were observed using instantaneous sampling with 10 min intervals in the entire 24 h 2
period, whereas social interactions were continuously scored for 6 hours between 3
09.00 and 15.00 hours.
4 5
Except from the PER treatment (P<0.05), the goats were resting more frequently 6
against walls in pens with any additional walls than in the control pen. The additional 7
walls did not have any significant effects on the goats total resting time, 8
synchronization of resting, time spent resting in the activity area or resting in body 9
contact. Furthermore, additional walls in the resting area had no significant effects on 10
the goats’ social interactions. In conclusion, the goats’ preference to rest against a 11
wall was better met in pens with addition walls compared to in the control pen (CON), 12
but the design of the additional walls needs further investigation in order to optimize 13
the goats’ use of the resting area.
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Keywords: goat; resting behaviour; walls; partitions 16
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1. Introduction
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Most animals have an inelastic demand to rest (Jensen et al., 2005). Several 20
researches have demonstrated that the size of the resting area has a great impact on 21
total lying time, synchronization of resting behaviour, aggressive interactions and 22
growth (e. g. Nielsen et al., 1997; Mogensen et al., 1997; Bøe et al., 2006; Andersen 23
and Bøe, 2007).
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Intensive animal husbandry does quite often not supply enough space for 1
simultaneous resting. Often the production systems have a high animal density which 2
leads to a higher competition for lying space and a reduced resting time for some 3
individuals (Fregonesi et al., 2007). Next after feed, Marsden and Wood-Gush (1986) 4
found that limited lying space caused most of the displacements in sheep. In a social 5
group, some animals may be able to monopolize attractive lying space and this forces 6
subordinate animals to rest in less attractive areas such as the activity- and dunging 7
area where often no litter is provided (Andersen and Bøe, 2007). Animals do not only 8
compete for resting space per se, but also for an attractive lying space. Most farm 9
animals have a preference to rest close to a wall (cattle: Stricklin et al., 1979; sheep:
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Marsden and Wood-Gush, 1986; Færevik et al., 2005; Bøe et al., 2006; goat:
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Andersen and Bøe, 2007; domestic fowl: Cornetto and Estevez, 2001). This may be 12
due to increased comfort, but this can also be explained as an anti-predator strategy 13
where they feel safer close to a wall than in an open area (e. g. Cornetto and Estevez, 14
2001). It has also been speculated that this distribution of animals along the wall 15
perimeter reflect individuals trying to maximize distance between each other within 16
the limited space of the captive environment (Stricklin et al., 1998). Installing 17
additional walls is both a way to increase the perimeter length of a pen as well as 18
artificially increasing visual distance between individuals when available space is 19
limited. Additional walls with different configurations in the resting area for sheep did 20
not succeed in increasing resting time or resting synchrony, and did not affect the 21
aggression level (Jørgensen et al., 2009a). Andersen and Bøe (2007) found that goats 22
rested in body contact less than 7% of the resting observations, and this was not 23
influenced by the size of the resting area. When the goats were offered a larger resting 24
area (1.0 m2/goat) they only spent around 3% of the resting observations lying in body 25
contact with another individual. This is much lower than in sheep that rest in body 1
contact around 60% of the resting observations with the same size of the resting area 2
(Bøe et al., 2006).
3 4
The aim of the present experiment was to investigate the effects of providing 5
additional walls in the resting area on the resting behaviour and social interactions in 6
goats. We predicted that the additional walls would meet the goats’ preference to rest 7
against a wall and limit body contact with other goats while resting. In addition, we 8
predicted that installing additional walls in the resting area would decrease the 9
competition to rest with wall support.
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2. Materials and methods
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2.1. Experimental set up 14
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The experimental set up was equal to the one used by Jørgensen et al. (2009a). Six 16
groups of four goats where systematically rotated in a Latin Square design between 17
six equally sized experimental pens, where five of them had different configurations 18
of additional walls in the resting area while one pen was kept as control without 19
additional walls (CON) (Figure 1). For each treatment, all groups and pens were video 20
recorded for a period of 24 hours, after an initial three day habituation period.
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(Figure 1 here) 23
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2. 2. Experimental pens and additional wall configurations 25
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The experiment was conducted in an insulated building with mechanical ventilation, 2
at the Norwegian University of Life Sciences for 4 weeks in October and November 3
2007. We used the same pens as in the study of Jørgensen et al. (2009a). Each pen 4
had a total area 6.0 m2 (3.0 x 2.0 m), giving 1.5 m2/goat, which meets the European 5
regulations for organic farming (Council Regulation (EC) No. 1804/1999). The pens 6
were divided in two; one resting area with solid wooden floor elevated 10 cm from the 7
ground and one activity/dunging area with concrete floor, each measuring 1.5 x 2.0 m 8
(giving 0.75 m2/goat) (Figure 2). A grid of wooden beams (approx. 5.0 cm high and 9
15.0 cm openings between beams) was placed on the floor in the activity area 10
(dunging area) to make this area less attractive as resting area. Along the length of the 11
front pen wall (activity/dunging area) there was a horizontal feed opening (2.0 m, post 12
and rail design), which gave 0.5 m of feeding space per goat.
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(Figure 2 here) 15
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The experimental treatments had the following configurations of additional walls 17
(Figure 1): parallel wall (PAR), cross walls (CRO), perpendicular wall (PER), 18
cubicles (CUB) and three walls (THR). The parallel wall and perpendicular wall was 19
1.20 m high and 0.75 m wide, cross wall was 1.20 m high and 0.60 m wide, each 20
additional wall in the cubicle pen was 1.20 m high and 0.75 m wide with 0.50 m 21
between each cubicle, and the pen with the three walls had one wall (on the opposite 22
side of feed barrier) on 1.20 x 0.60 m and two walls on 1.20 x 0.50 m. All additional 23
walls were made of solid wood.
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2. 3. Animals and feeding 1
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A total of 24 healthy, dehorned and pregnant, Norwegian dairy goats were weighed 3
and randomly divided into groups of four animals (mean weight ± SE; 58.9 kg ± 1.3 4
kg; mean age: 4.2 ± 0.3 years). At the start of the experimental period, the goats were 5
on average seven weeks pregnant. All goats were individually marked across their 6
back (1-4) using a marker spray for animals (Jet Mark®, Os Husdyrmerkefabrikk, 7
Norway). The goats were fed twice a day, in the morning between 08.00 and 09.00 8
hours and in the afternoon between 14.00 and 15.00 hours. Good quality hay was 9
offered ad libitum, and the goats had free access to water from buckets placed in the 10
feeding trough in front of the pen. Once a day hay residuals were removed and goats 11
were fed a standard concentrate pellet diet (approximately 0.2 kg per goat) before 12
fresh hay was administered. In addition to this, the goats had free access to mineral 13
blocks. Twice a day, faeces and urine was removed from the resting area and a thin 14
layer of sawdust was administered to ensure a dry and non-slippery surface. The 15
activity/dunging area was cleaned out twice a week so that the level of faeces always 16
was kept below the wooden grids.
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2. 4. Behavioural observations 19
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A wide angle video camera (Netdale/QMD C-C/5 colour CCTV) was suspended 21
above each pen and directly connected to a computer using the MSH video system®
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(www.guard.lv). We recorded the goats’ behaviour for 24 hours, starting at morning 23
feeding (09.00 hours) on the fourth day in each pen treatment.
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2. 4. 1. Resting behaviour and general activity 1
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Resting behaviours and general activities were scored using instantaneous sampling 3
method every 10 minutes for 24 hours using the following ethogram:
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- Resting against the original pen wall*
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- Resting against the additional wall*
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- Resting in the resting area without any contact with the pen or the additional 8
walls 9
- Resting in the activity area 10
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* In order to determine if goats were resting against a wall or just accidently in 12
contact with it, we defined ‘resting in contact’ when the goat was resting in physical 13
contact with at least its front half of the body (neck to belly). If the goat was resting 14
with its hind half of the body in contact with the wall, the behaviour was categorized 15
in relation to how much of the body was in physical contact with the wall. A goat 16
resting with its shoulder in contact with an original wall but also with its hindquarters 17
in contact with an additional wall was scored as resting against the original pen wall.
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In addition to this, we recorded whether a goat was resting in body contact (with one 20
or several goats) or without any physical contact with another goat. All observations 21
of resting behaviours were later summed to give the percent of total observations 22
resting, and for each observation, we also calculated number of goats that were resting 23
simultaneously. When all four goats in the same pen were resting at the same time, 24
they were resting synchrony.
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2. 4. 2. Social interactions 2
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Social interactions were scored continuously during six hours between 09.00 and 4
15.00 hours. Which individuals who performed or received an agonistic behaviour 5
was also recorded. The following ethogram of mutually exclusive behaviours was 6
used:
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- Butting with the head against the head or body of another goat 9
- Chasing (moving quickly after) another goat 10
- Pushing (push away another goat with its head or body) 11
- Displacing (a goat physically forcing another goat to leave its resting position 12
by pushing or butting) 13
- Withdrawing (a goat runs away from another goat after a social interaction) 14
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Numbers of butting, chasing, pushing and displacing were summarized into the term 16
aggressive behaviours.
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2. 5. Statistical analysis 19
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To analyze the effects of the different treatments on resting behaviour and social 21
interactions we used a mixed model of analysis of variance in the statistical program 22
SAS (SAS institute Inc, 1989), with wall configuration (six different treatments) and 23
group (1 to 6) as class variables. Group was specified as a random effect (Hatcher and 24
Stephanski, 1994). The Least squares means test was used to investigate differences 1
between means. Mean values per group were used as statistical unit.
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3. Results
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3. 1. Resting behaviour 6
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There were no differences between pen treatments in total resting time (from 64.9 to 8
67.7% of total observations, Table 1). Resting synchrony was similar in all treatments 9
(from 39.4 % to 43.6 % of total observations, Table 1). Some goats were occasionally 10
resting in the activity area, but there was no effect of treatment (Table 1). The goats 11
rarely rested in body contact; on average 10.9 % of the observation resting (range:
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7.2-15.2 % obs. resting) in body contact with one goat, and even more seldom in body 13
contact with more than one goat (Table 1). There was no significant difference 14
between groups with respect to total resting time, synchrony in resting, resting in the 15
activity area, and resting in body contact with one or several goats.
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3. 2. Resting against additional walls 18
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Except for the PER-treatment (perpendicular wall), the goats spent more time (% of 20
observations resting) resting against the original pen wall in the control pen than in all 21
the other pens (Table 1). The additional walls were most used in the cubicle treatment 22
(Table 1) and here the goats were mostly lying inside the cubicles with their heads 23
towards the pen wall. The perpendicular (PER) walls appeared to be the least 24
preferred. Except from the PER configuration, the goats were resting more (% of obs.
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resting) with wall support (pen wall + additional wall) in the experimental pens 1
compared to the control pen (Table 1). Resting against the pen wall and the additional 2
wall did not differ significantly between groups.
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Between the goats within group there was large difference in how much each goat 5
was resting with wall support (range 1-100 % of obs. resting). Some goats were 6
resting more against the pen wall and correspondingly less against the additional wall, 7
and vice versa for the other goats. In every group there was one goat that was resting 8
more in the activity area than the other group members, and typically this goat was 9
resting with least wall support.
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(Table 1 here) 12
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3. 3. Social interactions 14
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Displacements from the resting area were relatively infrequent (mean 0.55 per goat/6 16
h) and there was no effect on treatment (Table 1). Aggressive behaviours occurred on 17
average 6.8 per goat, but there was no effect of treatment (Table 1). There were no 18
significant differences between groups in amount of aggressive behaviours or 19
displacements in the resting area.
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4. Discussion
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Similar to what was found in sheep (Jørgensen et al., 2009a), the present experiment 24
showed that additional walls in the resting area had no effects on the goats’ total 25
resting time, synchrony of resting behaviour, time spent resting in the activity area or 1
resting in body contact. Furthermore, the additional walls in the resting area did not 2
succeed in reducing aggressive interactions.
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The biggest difference between the present study and the one in sheep (Jørgensen et 5
al., 2009a), was the percentage of observations resting against the additional wall in 6
the pen with cubicles (goat: 84.9 % vs. sheep: 32.3 %) and three walls (goat: 42.5 % 7
vs. sheep: 29.6 %). Sheep rested more in the activity area in the pen treatment with 8
cubicles than goats. This may suggest that sheep do not like cubicles and try to avoid 9
them, whereas this was the most preferred configuration of additional walls for goats.
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During day time, female mountain goats spend around 50 % of their time resting and 12
30 % at dusk (Hamel and Côté, 2008). In this experiment, the goats rested on average 13
66.4 % of total observations, which is close to what Andersen and Bøe (2007) found 14
in goats with the same sized pen- and resting area (64.1% of tot. obs.).
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Generally, animals tend to have synchronized resting- and activity pattern (Rook and 17
Penning, 1991). The synchronization of resting was higher in this experiment (mean ± 18
SE for all groups: 41.7 ± 1.7% of tot. obs.) than what we have previously found in 19
goats (Andersen and Bøe, 2007). In the previous experiment the goats rested 20
simultaneously only in 8.5 % of total observations with a resting area of 0.75 m2/goat 21
and 21.1 % of total observations with a resting area of 1.0 m2 per goat. When using a 22
two-level resting area the goats tended to reduce the synchrony in resting and this may 23
explain some of the differences in simultaneous resting behaviour between these two 24
studies.
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1
The goats used the additional walls to a large extent and this increased the percentage 2
of resting with wall support in the experimental pens compared to the control pen 3
(except from the perpendicular wall). These results show that goats have a preference 4
to rest against a wall, which is in accordance with previous studies on other farm 5
animals (cattle: Stricklin et al., 1979; sheep: Marsden and Wood-Gush, 1986;
6
Færevik et al., 2005; Bøe et al., 2006; fowl: Cornetto and Estevez, 2001). Some 7
configurations demand more space than others, especially the CRO and the THR 8
treatment. Goats in these two pen treatments had limited opportunities to vary their 9
resting positions because the configuration only allowed them to rest in one or two 10
specific directions and we observed that some goats were able to block other goats out 11
from the resting area by their resting position.
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Additional wall is an artificial way to increase the distance between individuals and to 14
keep potential opponents out of visual contact. However, both in this study and in the 15
sheep experiment (Jørgensen et al., 2009a), physical barriers in the resting area did 16
not appear to reduce aggression.
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It is not clear if the results from this study can be extrapolated to larger groups. When 19
increasing the group size, but maintaining the space allowance per individual, the perimeter 20
length will actually decrease (Stricklin et al., 1995; Jørgensen et al., 2009b). Hence, 21
additional walls may in fact have a more distinct effect in larger group sizes. Increasing the 22
total space allowance will obviously also increase the perimeter length (Bøe et al., 2006), 23
but also make it possible to install additional walls with less opportunities to block 24
others from resting. However, it is unlikely that a larger resting area will be used 25
1
In conclusion, the goats rested more against walls in pens with additional walls in the 2
resting area than in the control pen. These results suggest that installing additional 3
walls in the resting area would meet the goats’ preference for wall support when 4
resting, but with no consequences for aggression or resting pattern.
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Acknowledgements
7 8
The experiment was financially supported by grants from the Norwegian Research 9
Council, Agricultural Agreement Research Fund and Foundation for Research Levy 10
on Agricultural Products. The authors would like to thank Agnes Klouman and her 11
colleagues for feeding and taking care of the goats through the experimental period.
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Table 1
Table 1. Mean ± SE % of total observations or observations resting on resting behaviour, numbers of displacements from the resting area and 2
total number of aggressive behaviours for all pen treatments.
3 4
Behaviours
Control (CON)
Parallel wall (PAR)
Cross walls (CRO)
Perpendicular wall (PER)
Cubicles (CUB)
Three walls (THR)
F5,25 P-value
Total resting time (% of total obs.) 67.7 ± 2 .5 66.6 ± 3.0 66.9 ± 2.1 67.1 ± 1.5 64.9 ± 3.2 65.1 ± 3.2 0.3 ns All goats resting simultaneously (% of total obs.) 43.6 ± 2.2 39.5 ± 2.5 41.9 ± 2.2 43.6 ± 1.3 39.4 ± 2.3 42.0 ± 4.7 0.2 ns Resting in the activity area (% of obs. resting) 8.7 ± 4.6 12.2 ± 5.3 11.3 ± 4.0 10.6 ± 4.8 6.8 ± 3.9 14.4 ± 5.8 0.6 ns Resting against a pen wall (% of obs. resting) 71.7 ± 5.9 a 57.2 ± 7.6 b 61.3 ± 5.3 be 67.8 ± 6.2 ae 6.0 ± 5.6 c 40.4 ±7.1 d 67.4 < 0.0001 Resting against additional walls (% of obs. resting) - 28.9 ± 6.5 a 26.6 ± 4.7 a 13.0 ± 3.3 b 84.9 ± 4.9 c 42.5 ± 6.0 d 81.5 < 0.0001 Resting in the resting area with wall support
(% of obs. resting) 71.7 ± 5.9 a 86.0 ± 5.2 b 87.9 ± 4.1 b 80.9 ± 5.6 ab 90.9 ± 4.0 b 82.9 ± 6.1 b 3.34 < 0.05 Resting in resting area without wall support
(% of obs. resting) 19.6 ± 4.7 a 1.8 ± 0.7 b 0.7 ± 0.4 b 8.5 ± 2.9 cd 2.3 ± 1.0 bd 2.7 ± 1.8 bd 11.2 < 0.0001 Resting in body contact with one goat
(% of obs. resting) 13.3 ± 3.0 7.2 ± 2.2 10.9 ± 1.9 15.2 ± 2.5 9.7 ± 3.0 9.3 ± 3.0 0.8 ns
Resting in body contact with more than one goat
(% of obs. resting) 0.4 ± 0.3 0.4 ± 0.2 0.0 ± 0.0 0.2 ± 0.2 0.7 ± 0.4 0.1 ± 0.1 0.7 ns
No. of displacements from the resting area per goat/6 h 0.6 ± 0.1 0.8 ± 0.2 0.6 ± 0.1 0.3 ± 0.2 0.7 ± 0.2 0.3 ± 0.1 0.2 ns No. of aggressive behavioursf per goat/6 h 5.5 ± 1.2 6.4 ± 0.9 9.6 ± 2.4 7.2 ± 2.4 5.7 ± 1.2 6.2 ± 1.6 0.5 ns ns = not significant. Different letters show significant differences between pen treatments.
5 f Aggressive behaviours include butting, chasing, pushing and displacements from the resting area.
6
Legend to figures 1
2
Figure 1.
3
The control pen and five treatment pens, with their different configuration of the additional 4
walls installed in the resting area.
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1: control pen, 2: horizontal wall, 3: cross wall, 4: perpendicular wall, 5: cubicles, 6: three 6
walls.
7 8
Figure 2. The experimental pen with resting area (grey), feed barrier and activity area with 9
wooden grids on the floor.
10 11 12 13
1
Control (CON)
Parallel wall (PAR)
Cross wall (CRO)
Perpendicular wall (PER)
Cubicles (CUB)
Three walls (THR)
2 3
Figure 1 4
5 6 7 8
1
2 . 0 0 m
3.00m 1.50m
R e s t i n g a r e a ( 0 . 7 5 m p e r a n i m a l )
F e e d b a r r i e r A c t i v i t y / d u n g i n g a r e a
2
2 3
Figure 2 4