Poor-fitting tack and lameness linked to abnormal behaviours in horses

Abnormal behaviours by horses during tacking-up or mounting likely reflect lameness or tack-related discomfort, the authors of a just-published study conclude. Dr Sue Dyson and her colleagues set out to explore the relationship between a range of common problems and horse behaviour while being tacked-up and mounted.

The factors explored included the presence of abnormal tension or pain in the long (epaxial) muscles on top of the horse’s back, girth region sensitivity, static and dynamic saddle fit for the horse, saddle fit for the rider, rider position and balance, and lameness or abnormalities during a canter.

The epaxial muscles beneath and behind the saddle have an important role in movement and postural control of the horse’s back.

Increased epaxial muscle tension or pain may reflect a primary back problem, or develop secondary to lameness, poor saddle fit or a poorly balanced rider. The study, reported in the journal Equine Veterinary Education, involved 193 sports and leisure horses recruited from 11 locations, with both amateur and professional riders. The researchers used a purpose-designed protocol to document behaviour during tacking-up and mounting, comprising 64 abnormal behaviours for tacking-up, and 30 for mounting. Behaviours ranged from biting, ears back, fidgeting and tail swishing, to head-tossing, staring, having the tongue out, nose rubbing and licking. Each horse was observed for about eight minutes by Dyson, the lead researcher, while specific information was collected relating to the rider’s recollection of the horse’s behaviour during tacking-up and mounting, as well as details of professional input into saddle and bridle fit.

Each horse then underwent a careful, systematic palpation of the epaxial muscles under and behind the saddle by Dyson. Pain on palpation was usually revealed through an alteration of behaviour, such as laying the ears back, swishing the tail, or fidgeting. Each horse was observed by Dyson while the rider tacked-up and mounted as they normally would, during which she noted any abnormal horse behaviours. The saddle fit for the horse was assessed before and after mounting. Before the horse was mounted it was evaluated moving in-hand and the presence and severity or absence of lameness was recorded by Dyson.

Each horse was ridden around the periphery of an arena at the walk, trot and canter on both the left and right reins, and in circles of 20-metre and 10-metre diameter at the trot. Jenny Routh assessed the presence of lameness, grading it on a scale of 0 to 8, and recorded abnormalities of canter, such as lack of a suspension phase. Anne Bondi recorded abnormal movement of the saddle, such as oscillating from side to side, slipping to one side, or bouncing.

Video recordings were taken of the ridden exercise phase so that the previously developed Ridden Horse Pain Ethogram could be applied retrospectively. Data on the lameness grading and ethogram scores were combined to give an overall lameness severity score. This takes into account that a horse with bilateral lameness is likely to be underscored using a simple lameness grading scale. Each rider’s position in the saddle, balance and size in relation to the saddle were evaluated during ridden exercise by Bondi.Riding school horses comprised only 12% of the 193 horses, but they were found to have higher rates of abnormal behaviours during both tacking-up and mounting compared with the general-purpose horses, which included horses used for unaffiliated-level competition.

Horses with moderate or severe lameness (for example, an ethogram score of 9 and lack of hindlimb impulsion) were 1.4 times more likely to display abnormal behaviour during tacking-up than non-lame horses.

Horses found to be lame in-hand or ridden had 1.5 times higher rates of abnormal behaviour during mounting than non-lame horses. The overall saddle fit score, combining static and dynamic fit, was positively associated with the number of behaviours shown during mounting.

Tight saddle tree points and epaxial muscle pain were linked to more abnormal behaviours during tacking-up. The authors said epaxial muscle pain was a significant factor associated with tacking-up problems, although it was seen in only a small number of horses. “It may be secondary to lameness or altered range of motion of the thoracolumbosacral region associated with an ill-fitting saddle, or a combination of factors, including rider position, size and balance,” Dyson and her colleagues said.

The proportion of ill-fitting saddles was disturbing. The high prevalence of ill-fitting saddles, and their influence on behaviour and performance, pointed to the need for regular saddle-fit checks, at least every six months, they said.

They suggested the higher levels of abnormal behaviours seen in these horses during tacking-up may be in anticipation of pain, either caused directly by the tack or musculoskeletal pain during ridden exercise.

The researchers found no effect of girth region hypersensitivity on behaviour during tacking-up or mounting, but they stressed that, for some horses, this may be a potentially significant factor. The study team said horse owners must be better educated to recognise abnormal behaviours during tacking up and mounting, and advised to seek professional advice. “Saddle, bit and bridle fitters also need to be aware of the potential significance of equine behaviour during tacking-up and mounting.”Dyson is a lameness specialist and independent clinical consultant. Bondi is a rider and trainer who founded the Saddle Research Trust. Routh and fellow research Danica Pollard (who contributed to data analysis and interpretation), are former employees of the Animal Health Trust.

An investigation into the relationship between equine behaviour when tacked-up and mounted and epaxial muscle hypertonicity or pain, girth region hypersensitivity, saddle-fit, rider position and balance, and lameness