Plus-Hex CLINICAL
Table 1 . Criteria used for the assessment of the serval ' s gait via video recordings as part of regular monitoring .
Criteria
Assessment description
1 ( Normal ) 0 ( Abnormal )
Participation
Limb arc of flight
Stride
Stationary weight bearing
Locomotive weight bearing
Posture ( head , neck and pelvis )
Willingly participates in movement with no hesitation .
Even and as expected limb protraction and retraction . Even hock and carpus lift and no evidence of paw rotation .
Distance between one ground mark and the next made by the same paw is even . Normal stride length .
All feet resting on the ground squarely with even distribution of weight . No toe touching or weight shifting .
While moving , all feet touch ground with full weight bearing . Stance phase of movement is even .
Head carriage normal . Shoulders and pelvis level , spring through the back present ( flexion / extension ), movement is free , not stiff or jolted .
Animal hesitates for 5 seconds or more before starting movement .
Reduced protraction or retraction of a limb , uneven height of hock or carpus . Visible rotation ( pronation / supination ) of foot .
Distance between one ground mark and the next made by the same paw is uneven . Shorter or longer stride length .
One limb held off floor , or toe touching , or limb visibly trembles / shakes when weight bearing , weight shifting or uneven stance .
Uneven distribution of weight in stance phase . May only touch toe to floor , not flat of foot .
Head bobbing , neck extended or head carried low . Uneven level to shoulders and pelvis , tucked or crouched posture , stiff movement and minimal / no spring through the back .
Turning
Inside limb takes small stride , outside limbs take longer strides . Turn is a smooth movement . Limbs parallel , no abduction .
Visible wobble or imbalance , hop or other jerky movement . Hesitation for at least 5 seconds before performing turn .
Enclosure modifications were made to enable the serval to access all areas of the enclosure without jumping . Because of the animal ' s lack of claws , ramps were covered in Astroturf to provide grip . The addition of wooden ‘ steps ’ also eased navigation , particularly on descent . The bed area was elevated and provided a warm , draught-free look-out area – the serval spent an increasing amount of time here as the disease progressed , particularly on cold mornings .
Exercise and activity levels
The serval was retired from public demonstrations in August 2019 but continued daily walks and exercise . This encouraged mobility and enabled keepers to assess its activity levels , gait and general demeanour . A reduction in daily activity is a common clinical sign in domestic cats with OA ( Guillot et al ., 2013 ) and this was reflected in this case . As the disease progressed , the serval became less engaged with enrichment items and hesitant to exercise .
A rapid assessment of the serval ' s activity levels and engagement with keepers enabled the tracking of behaviours over time . A tick-sheet describing activity level ( active or stationary ), enclosure usage ( levels and ramps accessed ), movement ( any stiffness or lameness detected ), engagement with enrichment and willingness to participate in training was completed five times per day ( Table 2 , overleaf ). Exercise and diet modification helped to manage body weight , a key factor in the management of OA , as obesity increases pressure on joints and is likely to worsen OA and pain .
Disease progression and end-of-life care
In May 2020 , 15 months after the initial diagnosis , the animal deteriorated , following an episode of pacing and a suspected fall . There was increased bilateral laxity in the carpi when walking , with intermittent buckling of the left carpus . An increased amount of time was spent lying down and the animal ' s hair appeared unkempt ,
Volume 37 ( 4 ) • September 2022
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