Basic Needs in Horses?—A Literature Review

Abstract

Every animal species has particular environmental requirements that are essential for its welfare, and when these so-called “basic needs” are not fulfilled, the animals suffer. The basic needs of horses have been claimed to be social contact, social companionship, free movement and access to roughage. To assess whether horses suffer when one or more of the four proposed basic needs are restricted, we examined several studies (n = 38) that reported behavioural and physiological reactions to these restrictions. We assigned the studies according to the four types of responses investigated: (a) Stress, (b) Active, (c) Passive, and (d) Abnormal Behaviour. Furthermore, the number of studies indicating that horses reacted to the restrictions were compared with the number of studies reporting no reaction. The limited number of studies available on single management restrictions did not allow conclusions to be drawn on the effect of each restriction separately, especially in the case of social companionship. However, when combinations of social contact, free movement and access to roughage were restricted, many of the horses had developed responses consistent with suffering. Passive Responses, indicating acute suffering, and Abnormal Behaviour, indicating suffering currently or at some time in the past, were especially clearly demonstrated. This provides further evidence of the usefulness of assessing behavioural parameters in combination with physiological measurements when evaluating horse welfare. This meta-analysis of the literature confirms that it is justified to claim that social contact, free movement and access to roughage are basic needs in horses.

Need or opportunity? A study of innovations in equids

“…Actions (N = 109) which were not innovative because they were: either reported to be about trained behaviour: people confirmed our questions of whether they trained the behaviour or reinforced the behaviour verbally or with food; or they were behaviours frequently shown in equids [ 29 , 30 ]: for example, horses defecating on piles, or horses jumping over fences and feeding on the grass on the other side of the fence; possibly the result of reduced welfare, but useless for finding a solution for the underlying deficiency [ 27 , 30 ]: for example, a horse showing repetitive, stereotypic behaviour when scraping the ground with a toy. …”

“…possibly the result of reduced welfare, but useless for finding a solution for the underlying deficiency [ 27 , 30 ]: for example, a horse showing repetitive, stereotypic behaviour when scraping the ground with a toy.…”

“…A suitable range of conditions for studying whether animals innovate out of need or out of opportunity is offered by captive mules, donkeys and horses, just because their environment is strongly influenced by human management. For instance, the needs of domestic equids [ 27 ] for movement of up to 30 km a day [ 28 ], for foraging for 12 to 16 hours a day [ 28 – 30 ], and for social contact [ 29 , 31 – 35 ] are not covered in many management systems, which potentially causes stress, reduced physical welfare [ 36 ] and mental imbalance [ 37 ]. Abnormal [ 38 , 39 ] and depressive-like behaviour [ 27 , 40 ] may occur.…”

“…For instance, the needs of domestic equids [ 27 ] for movement of up to 30 km a day [ 28 ], for foraging for 12 to 16 hours a day [ 28 – 30 ], and for social contact [ 29 , 31 – 35 ] are not covered in many management systems, which potentially causes stress, reduced physical welfare [ 36 ] and mental imbalance [ 37 ]. Abnormal [ 38 , 39 ] and depressive-like behaviour [ 27 , 40 ] may occur. Individuals’ attempts to mitigate such problems may stimulate innovations associated with movement, foraging, and social contact [ 11 , 41 – 43 ].…”

“…Animals may innovate out of need when the social environment is unstable and out of opportunity when it is stable [ 16 – 18 , 21 ]. Finally, animals may innovate because of the opportunities from play and when human management covers their basic needs [ 24 , 25 , 27 ].…”