Grete H M Jørgensen

Research Scientist

(+47) 407 66 769
grete.jorgensen@nibio.no

Place
Tjøtta

Visiting address
Parkveien, 8861 Tjøtta

To document

Abstract

In recent years, slatted floors made of materials like fiber composite and plastic have been introduced in animal housing systems. These modern floor types are claimed to have low heat conductivity and hence be “better” for the sheep than expanded metal, but the actual preference in sheep has not yet been tested. The aim of this study was to investigate the preference of ewes for different floor materials at low ambient temperatures. The experiment was performed in a non-insulated building and the indoor air temperature varied from -11.8 to + 3 °C. Each experimental pen measured 3.0 x 2.0 m (total 6.0 m2) and were divided into two equal sections (A and B). A total of 30 non-pregnant ewes were sheared and allocated to one of ten stable groups with three animals per group. Five different floor types – expanded metal, slatted floor made of fiber composite, slatted floor made of plastic, solid floor made of wood and solid floor consisting of a rubber mat, were installed in section A and B in the experimental pens. Groups were habituated to all floor material combinations and systematically rotated through the ten pens. Behaviors were scored from 20 hour video recordings using instantaneous sampling at 10 minute intervals. In addition, heat conductivity properties of the five different floor materials were tested. On days with low temperatures, the ewes were standing or walking more, resting less, eating or drinking more and resting more in physical contact than on days with higher temperatures. When given the choice, ewes showed clear preferences for standing/walking and resting on solid floor materials than on slatted floors. This is consistent with earlier preference tests on sheared sheep. Ewes did not seem to show a clear preference for one slatted floor material over another for resting. The proportion of time spent standing/walking in the pen was steadily reduced as air temperature in the barn increased. The present experiment suggests that none of the floor combinations had thermal properties that adversely affect resting and other general behaviors of the animals. The heat conductivity properties were similar among the slatted floors. In conclusion, the claimed favorable thermal properties of plastic slatted floors and fiber composite were not confirmed. There must be other properties of the floor than heat conductivity that influences the preference in ewes.

To document

Abstract

In recent years, slatted floors made of materials like fiber composite and plastic have been introduced in animal housing systems. These modern floor types are claimed to have low heat conductivity and hence be “better” for the sheep than expanded metal, but the actual preference in sheep has not yet been tested. The aim of this study was to investigate the preference of ewes for different floor materials at low ambient temperatures. The experiment was performed in a non-insulated building and the indoor air temperature varied from -11.8 to + 3 °C. Each experimental pen measured 3.0 x 2.0 m (total 6.0 m2) and were divided into two equal sections (A and B). A total of 30 non-pregnant ewes were sheared and allocated to one of ten stable groups with three animals per group. Five different floor types – expanded metal, slatted floor made of fiber composite, slatted floor made of plastic, solid floor made of wood and solid floor consisting of a rubber mat, were installed in section A and B in the experimental pens. Groups were habituated to all floor material combinations and systematically rotated through the ten pens. Behaviors were scored from 20 hour video recordings using instantaneous sampling at 10 minute intervals. In addition, heat conductivity properties of the five different floor materials were tested. On days with low temperatures, the ewes were standing or walking more, resting less, eating or drinking more and resting more in physical contact than on days with higher temperatures. When given the choice, ewes showed clear preferences for standing/walking and resting on solid floor materials than on slatted floors. This is consistent with earlier preference tests on sheared sheep. Ewes did not seem to show a clear preference for one slatted floor material over another for resting. The proportion of time spent standing/walking in the pen was steadily reduced as air temperature in the barn increased. The present experiment suggests that none of the floor combinations had thermal properties that adversely affect resting and other general behaviors of the animals. The heat conductivity properties were similar among the slatted floors. In conclusion, the claimed favorable thermal properties of plastic slatted floors and fiber composite were not confirmed. There must be other properties of the floor than heat conductivity that influences the preference in ewes.

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Abstract

Many horse stables have mechanical-fan ventilation systems but still try to regulate ventilation manually by closing doors and windows on a cold winter night. The aim of this study was to investigate the variation in air quality in Norwegian horse stables with different ventilation systems on days with low outdoor air temperatures. A total of 19 insulated, mechanically ventilated stables with horses kept inside during the night were included in the study. Almost all fans were operated during the night (n=18), but inlets for fresh air were highly variable in design and management leading to potential for ineffectiveness of ventilation functions. In four of the stables, there were no specific air inlet systems, and in five stables, the exit door was used as the only air inlet. The air exchange rate was sufficient in all the stables with an automated temperature thermostat for ventilation control. Mean level of carbon dioxide (CO2) was 1,800 ppm and in one stable CO2 exceeded 3,000 ppm. Mean inside ammonia (NH3) was 1.3 ppm, and only in one stable the level of NH3 exceeded 5 ppm. The total dust concentration was 0.69 ± 0.19 mg/m3, and in two stables, the dust concentration exceeded 1.0 mg/m3. Total and respirable dust levels were higher in stables with ventilation rate below recommended level. Half of the stables visited had a lower calculated air exchanges rate than recommended, and the majority of the stables regulated the ventilation manually by closing doors and inlets during night. This indicates a general lack of knowledge among the stable managers of climatic demand in horses and how to operate mechanical ventilation. Still, the majority of the stables maintained acceptable air quality, with NH3 and dust levels within recommended levels, although most stables had elevated humidity.

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Abstract

Limited information is available on the extent to which blankets are used on horses and the owners’ reasoning behind clipping the horse’s coat. Research on the effects of those practices on horse welfare is scarce but results indicate that blanketing and clipping may not be necessary from the horse’s perspective and can interfere with the horse’s thermoregulatory capacities. Therefore, this survey collected robust, quantitative data on the housing routines and management of horses with focus on blanketing and clipping practices as reported by members of the Swedish and Norwegian equestrian community. Horse owners were approached via an online survey, which was distributed to equestrian organizations and social media. Data from 4,122 Swedish and 2,075 Norwegian respondents were collected, of which 91 and 84% of respondents, respectively, reported using blankets on horses during turnout. Almost all respondents owning warmblood riding horses used blankets outdoors (97% in Sweden and 96% in Norway) whereas owners with Icelandic horses and coldblood riding horses used blankets significantly less (P < 0.05). Blankets were mainly used during rainy, cold, or windy weather conditions and in ambient temperatures of 10°C and below. The horse’s coat was clipped by 67% of respondents in Sweden and 35% of Norwegian respondents whereby owners with warmblood horses and horses primarily used for dressage and competition reported clipping the coat most frequently. In contrast to scientific results indicating that recovery time after exercise increases with blankets and that clipped horses have a greater heat loss capacity, only around 50% of respondents agreed to these statements. This indicates that evidence-based information on all aspects of blanketing and clipping has not yet been widely distributed in practice. More research is encouraged, specifically looking at the effect of blankets on sweaty horses being turned out after intense physical exercise and the effect of blankets on social interactions such as mutual grooming. Future efforts should be tailored to disseminate knowledge more efficiently, which can ultimately stimulate thoughtful decision-making by horse owners concerning the use of blankets and clipping the horse’s coat.

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Abstract

This paper describes a method in which horses learn to communicate by touching different neutral visual symbols, in order to tell the handler whether they want to have a blanket on or not. Horses were trained for 10–15 min per day, following a training program comprising ten steps in a strategic order. Reward based operant conditioning was used to teach horses to approach and touch a board, and to understand the meaning of three different symbols. Heat and cold challenges were performed to help learning and to check level of understanding. At certain stages, a learning criterion of correct responses for 8–14 successive trials had to be achieved before proceeding. After introducing the free choice situation, on average at training day 11, the horse could choose between a “no change” symbol and the symbol for either “blanket on” or “blanket off” depending on whether the horse already wore a blanket or not. A cut off point for performance or non-performance was set to day 14, and 23/23 horses successfully learned the task within this limit. Horses of warm-blood type needed fewer training days to reach criterion than cold-bloods (P < 0.05). Horses were then tested under differing weather conditions. Results show that choices made, i.e. the symbol touched, was not random but dependent on weather. Horses chose to stay without a blanket in nice weather, and they chose to have a blanket on when the weather was wet, windy and cold (χ2 = 36.67, P < 0.005). This indicates that horses both had an understanding of the consequence of their choice on own thermal comfort, and that they successfully had learned to communicate their preference by using the symbols. The method represents a novel tool for studying preferences in horses.

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Abstract

There is increasing interest in keeping horses in groups, but progress is hampered by a lack of knowledge about which horses can and should be kept together. Therefore, our objective was to investigate the effect of group composition on the occurrence of injuries among horses, the ease of removing horses from groups and horses’ reactivity to a fearful stimulus. Using a matched case control design, 61 groups of horses were studied in Denmark, Norway, Finland and Sweden. They were allocated into groups of similar or different age and sex or where membership changed regularly or remained stable. Injuries were recorded before mixing the horses into treatment groups, the day after mixing and four weeks later. Reactivity of horses to a moving novel object and the behaviour of a horse being removed from its group and the reactions of other group members towards this horse and the handler were evaluated. It was hypothesized that a more socially variable group composition has beneficial effects on behaviour, ease of handling and reducing reactivity whereas frequent changes in group composition has negative consequences, resulting in more injuries. We found that differences in treatment effects were mainly related to breed, rather than group composition. Icelandic horses reacted less to the movement of the novel object (P = 0.007) and approached it more afterwards (P = 0.04). They also had fewer new injuries than warmbloods following mixing (P < 0.001) and fewer than all other groups four weeks later (P < 0.01). Most new injuries after mixing were minor and recorded on the horse’s head, chest, hind legs and rump. In conclusion, variations in sex and age composition of the group had little effect on injury level, reactivity and ease of handling compared to the general effect of breed. Concerns about the risk of severe injuries associated with keeping horses in groups are probably overestimated. Thus, we propose that horses can be successfully kept in groups of different sex and age composition.

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Abstract

Keeping horses in groups is widely recommended but limited information is available about how this is implemented in practice. The aim of this survey was to describe how horses are kept in the Nordic countries in relation to sex, age, breed, and equestrian discipline and to assess owners’ attitudes toward keeping horses in groups. Horse owners in Denmark, Finland, Norway, and Sweden were approached using a web-based questionnaire, which was translated into 4 languages and distributed online via equestrian forums, organizations, and social media. The number of respondents was 3,229, taking care of 17,248 horses. Only 8% of horses were never kept in groups, 47% were permanently grouped for 24 h/d, and 45% were stabled singly but grouped during turnout. Yearlings were most often permanently kept in groups (75%), mares and geldings more commonly during parts of the day (50 and 51%, respectively), and stallions were often kept alone (38%). Icelandic horses were more likely to be permanently kept in groups (36%) than warmbloods (16%) and ponies (15%). Twice as many competition horses (51%) were never grouped compared with horses used for breeding (20%) or leisure purposes (15%). The majority of respondents (86%) strongly agreed that group housing benefits horse welfare and that it is important for horses to have the company of conspecifics (92%). Nevertheless, not all horses were kept in groups, showing that attitudes toward group housing may not necessarily reflect current management. The risk of injury was a concern of many respondents (45%), as was introducing unfamiliar horses into already established groups (40%) and challenges in relation to feeding in groups (44%). Safety of people (23%) and difficulties handling groupkept horses (19%) were regarded as less problematic. Results suggest that the majority of horses have the possibility to freely interact with other horses, either as fulltime members of a group during 24 h/d or during turnout. Future research should address the extent to which being a part-time member of a group affects horse welfare. For permanent group housing to become more widespread, such as it is the case for most farm animals, future research could focus on solving some of the reoccurring problems perceived with keeping horses in groups. The dissemination of evidence-based information on all aspects around keeping horses in groups can ultimately stimulate further positive changes in the management of group-kept horses.

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Abstract

Reasons for performing study: Horses may adapt to a wide range of temperatures and weather conditions. Owners often interfere with this natural thermoregulation ability by clipping and use of blankets. Objectives: To investigate the effects of different winter weather conditions on shelter seeking behaviour of horses and their preference for additional heat. Study design: Observational study in various environments. Methods: Mature horses (n=22) were given a free choice test between staying outdoors, going into a heated shelter compartment or into a nonheated shelter compartment. Horse location and behaviour was scored using instantaneous sampling every minute for one hour. Each horse was tested once per day and weather factors were continuously recorded by a local weather station. Results: The weather conditions influenced time spent outdoors, ranging from 52 % (of all observations) on days with mild temperatures, wind and rain to 88 % on days with less than 0°C and dry weather. Shivering was only observed during mild temperatures and rain/sleet. Small Warmblood horses were observed to select outdoors less (34 % of all observations) than small Coldblood horses (80 %). We found significant correlations between hair coat sample weight and number of observations outdoors (ρ = 0.23; P = 0.004). Conclusions: Horses selected shelters the most on days with precipitation and horses changed from a nonheated compartment to a heated compartment as weather changed from calm and dry to wet and windy. Horse breed category affected the use of shelter and body condition score and hair coat weight were associated with voluntary shelter selection.

Abstract

The aim of this experiment was to investigate the effects of different winter weather conditions on shelter seeking behaviour of horses and their preference for additional heat. A total of 17 horses from different breeds were habituated to an experimental paddock with a double-room shelter. In one of the rooms a 1500 W infrared heater provided radiation heat, the other room was not heated. The horses were turned out in their regular paddocks for two hours and then moved to the experimental paddock, where they could stay either in the heated room, in the non-heated room or outside in the 10x6 m paddock. Using instantaneous sampling at one-minute intervals for one hour, a present observer recorded horse’s behaviour and location. A weather station recorded data on wind (directions and speed), precipitation, temperature and sunshine. We registered the horses’ breed, exercise level, body weight, height and body condition, and samples of the horses’ coats were taken for length and quality registration. A Kruskal Wallis test was performed on the preliminary data. We observed great individual differences in the horses’ preferred location under different weather conditions. Horses increased their activity during low temperatures, combined with wind and/or rain (P<0.05). Ponies and warmblood horse breeds used the heated room to a greater extent than cold blood horse breeds (P<0.05). Horses with a low coat sample weight used the shelter more than horses with a large coat sample weight (P<0.05), and individuals with a large body condition score moved around more than individuals with a low body condition score (P<0.05). Muscle shivering was only observed during mild weather and rain. In conclusion, not only the horses breed but its body condition and coat characteristics also affect thermoregulation during winter weather. General activity also seemed to increase with wind, low temperatures and rain.

Abstract

The aim of this experiment was to investigate the effects of different winter weather conditions on shelter seeking behaviour of horses and their preference for additional heat. A total of 17 horses from different breeds were habituated to an experimental paddock with a double-room shelter. In one of the rooms a 1500 W infrared heater provided radiation heat, the other room was not heated. The horses were turned out in their regular paddocks for two hours and then moved to the experimental paddock, where they could stay either in the heated room, in the non-heated room or outside in the 10x6 m paddock. Using instantaneous sampling at one-minute intervals for one hour, a present observer recorded horse’s behaviour and location. A weather station recorded data on wind (directions and speed), precipitation, temperature and sunshine. We registered the horses’ breed, exercise level, body weight, height and body condition, and samples of the horses’ coats were taken for length and quality registration. A Kruskal Wallis test was performed on the preliminary data. We observed great individual differences in the horses’ preferred location under different weather conditions. Horses increased their activity during low temperatures, combined with wind and/or rain (P<0.05). Ponies and warmblood horse breeds used the heated room to a greater extent than cold blood horse breeds (P<0.05). Horses with a low coat sample weight used the shelter more than horses with a large coat sample weight (P<0.05), and individuals with a large body condition score moved around more than individuals with a low body condition score (P<0.05). Muscle shivering was only observed during mild weather and rain. In conclusion, not only the horses breed but its body condition and coat characteristics also affect thermoregulation during winter weather. General activity also seemed to increase with wind, low temperatures and rain.

Abstract

Group housing of horses is not very widespread, despite obvious advantages for their development and mental well-being. One often expressed rationale for this is that horse owners are worried about the risk of injuries due to kicks, bites or being chased into obstacles. To address this concern, we developed and validated a scoring system for external injuries in horses to be able to record the severity of a lesion in a standardized and simple way under field conditions. The scoring system has five categories from insignificant loss of hair to severe, life threatening injuries. It was used to categorize 1124 injuries in 478 horses. Most of these horses were allocated to groups to study the effect of group composition (i.e. same age or mixed, same gender or mixed, socially stable or unstable groups) on behaviour and injuries. The material included mainly riding and leisure purpose horses of different breeds, age and gender. Most injuries occurred the day after mixing. Injuries of the more severe categories 4 and 5, which normally would necessitate veterinary care and/or loss of function for some time, were not observed at all. The vast majority of the recorded injuries were category 1 lesions (hair loss only). A few such injuries were found on most horses, some horses had none, and a few had many. The second most common injury type was category two (abration/scrape into, but not through the skin, and/or a moderate bruise/contusion). Category 3 injuries (a minor laceration and/or contusion with obvious swelling) were only recorded in a baseline subset of 100 riding horses, there comprising 4% of the injuries. Whereas most of the injuries were found on the body, the category 3 injuries were mainly found on the limbs and head. The reason for this is probably that the skin there is tight and thus is more easily lacerated. Icelandic horses tended to have fewer and less severe injuries compared to other breeds. There was also a breed effect on location of the injuries. We conclude that the risk for serious injuries when horses are kept in groups is generally low and fear of injuries should not be a reason to prevent horses from social interaction with other horses. However, we emphasize that most of the recordings were performed during the summer period, and many horses were unshod. The situation might have been different in winter, and special caution should be taken if mixing horses shod with ice studs.

Abstract

Blanketing of horses is a very common management routine. Sometimes, this practice may seem unjustified. Therefore, we wanted to investigate the preferences of the horses themselves. First we developed a method by which the horse learned to communicate its wishes. Thirteen horses were trained to associate three different neutral visual symbols presented to them on a board with the actions 1) blanket is taken off, 2) blanket is put on, and 3) stay as is, and subsequently to communicate their wish by pointing at the relevant symbol. These horses had experience of wearing a blanket, but daily routines varied. All individuals which started the training programme succeeded in learning the task. Second, we tested the horse’ opinion under differing weather conditions. Horses normally wearing a blanket were tested with the blanket on, and those which normally did not, without. At the test days, the horse was taken out of its group and placed in a round pen. To be allowed to leave the round pen and join its pals again, the horse first had to make a choice among two symbols presented to them; to stay as is or to have the blanket removed/put on. The test was repeated under different climatic conditions (from -15 to + 20°C, sunny days and days with precipitation and wind) for each horse during winter, spring and autumn 2013. Preliminary results show that all horses made “sensible” choices. Nine out of the 13 horses wanted to remove the blanket for at least one test day. Naturally, cold blooded horses more often preferred to stay without, and shaved warm blooded horses more often preferred to stay blanketed. However, there were individual differences in both groups, showing that owner perception and the horse own opinion not always matched.

Abstract

Blanketing of horses is a very common management routine. Sometimes, this practice may seem unjustified. Therefore, we wanted to investigate the preferences of the horses themselves. First we developed a method by which the horse learned to communicate its wishes. Thirteen horses were trained to associate three different neutral visual symbols presented to them on a board with the actions 1) blanket is taken off, 2) blanket is put on, and 3) stay as is, and subsequently to communicate their wish by pointing at the relevant symbol. These horses had experience of wearing a blanket, but daily routines varied. All individuals which started the training programme succeeded in learning the task. Second, we tested the horse’ opinion under differing weather conditions. Horses normally wearing a blanket were tested with the blanket on, and those which normally did not, without. At the test days, the horse was taken out of its group and placed in a round pen. To be allowed to leave the round pen and join its pals again, the horse first had to make a choice among two symbols presented to them; to stay as is or to have the blanket removed/put on. The test was repeated under different climatic conditions (from -15 to + 20°C, sunny days and days with precipitation and wind) for each horse during winter, spring and autumn 2013. Preliminary results show that all horses made “sensible” choices. Nine out of the 13 horses wanted to remove the blanket for at least one test day. Naturally, cold blooded horses more often preferred to stay without, and shaved warm blooded horses more often preferred to stay blanketed. However, there were individual differences in both groups, showing that owner perception and the horse own opinion not always matched.

To document

Abstract

The aim of this experiment was to investigate the effect of increasing the number of ewes per nipple drinker on water intake, feed intake and drinking behaviour of ewes. A group of 30 1¾ year old, pregnant ewes of the Norwegian Dala breed were exposed to three treatments, each treatment lasting one week: 7.5 ewes per nipple drinker (N7.5: four nipple drinkers), 15 ewes per nipple drinker (N15: two nipple drinkers) and 30 ewes peer nipple drinker (N30: one nipple drinker). The experiment was performed both in January (week 4–6, replicate 1) and replicated in April (week 13–15, replicate 2). The ewes were kept in insulated building and had free access to good quality hay. Water metres were connected to the pipeline for water supply and water wastage was collected and weighed. In addition, the daily intake of hay was recorded and the ewes were video recorded the three last days of each experimental period. Total drinking time per individual was calculated from observations of drinking behaviour from the video, as were also incidents of queuing and displacements. Both water and feed intake was higher in replicate 2 than in replicate 1. Increasing the number of individuals per nipple drinker had no effect on water intake in replicate 1, whereas in replicate 2 the water intake was (mean±SE) 3.5±0.3; 4.2±0.1 and 4.9±0.1 l/ewe and day in the treatments N7.5, N15 and N30, respectively (P<0.05). Regardless of replicate, the time spent drinking increased significantly when number of ewes per nipple drinker increased. Queuing was not affected by increasing the number of ewes per nipple drinker. In replicate 1 the number of displacements increased significantly when the number of individuals per nipple drinker increased (N7.5=7.6±1.7; N15=15.0±4.2 and N30=36.7±5.2; P<0.05) and the same trend could be seen in replicate 2, although not significant. In conclusion, one nipple drinker with an acceptable flow rate can serve up to 30 ewes without negatively affecting water and feed intake