Horse husbandry concepts nowadays offer much more than just solutions for keeping horses physically healthy. Increasingly, the promotion of well-being and the avoidance of discomfort are central. In order to objectively assess horse husbandries a scientifically based advisory tool (BestTUPferd) was developed at the Technical University of Munich together with partners with the aim of improving animal welfare in horse husbandry. Horses in classical wide-spread single housing systems are dependent on an intensive exercise management, because they must be moved to outdoor areas and retrieved daily. The results of the data collection using BestTUPferd show that in 58 % of the single housing systems horses were brought to outdoor areas daily, but in almost half the farms (42 %, n = 10 farms), not all horses received daily free exercise (Ø 24 % of horses/farm). According to current knowledge, factors such as being with conspecifics, the size of the area, existing grass cover and offer of feeding places promote the exercise activity of horses. Such movement incentives are widespread on farms with group housing. A lack of free movement, as is often the case in single housings, can cause suffering and is therefore unacceptable. pauses between roughage meals in 7 % of the group housings and in 71 % of the single housings (GLMM, p<0.001; n = 15 group and n = 14 individual housings). These results confirm a previous study in which the proportion of horses in single housing with prolonged feeding pauses was 74.3 % (74 horses on 10 different farms on non-eating bedding). Hence, in single housings, the feeding pauses between the roughage meals are too long for the most part in traditional, two to three times daily, manual feeding on farms. Therefore, special attention must be paid to behaviorally appropriate feeding for those horses that do not have hay ad libitum and straw of forage quality permanently available, whose stalls are therefore littered with shavings, for example, and that are fed rationed feed. The lying area for horses kept individually should be at least (2 x Wh)2 and for horses kept in groups at least 3 x Wh2 in Germany. For a horse with a height at withers of 1.65 m, this corresponds to an area of 10.9 m2 and 8.2m2 respectively, which is very similar to the minimum requirements in Switzerland. In 15 % of the stalls per farm with individually stabled horses this value was not met. Overall, 38 % of the single housings (n = 16 farms) and 50 % of the group housings (n = 16 farms) were below the minimum requirements for the size of the lying area. In addition, on many farms there is a need for optimization with regard to the lying area design in terms of positioning, deformability of the bedding material and hygiene. Group housing not only fulfills the species-appropriate social behaviour of tactile contact significantly better than single housing, it also offers a more animal-friendly range of locomotion for horses. This is because 95 % of the farms with group housing (n= 19 farms) included an outdoor exercise area that was available 24 hours a day for seven days a week and was large enough (150m2 for the first two horses + 40 m2 per additional horse). Nevertheless, the high prevalence of superficial injuries in group housings shows how much there is a need for improvement in the welfare of group-housed horses, too (GLMM: p < 0.001, ≥1 injury: 74.3 ± 16,0 %, in single housings: 38.7 % ± 14.7 %). Common suggestions for improvements to reduce injuries in group housings include: o avoidance of frequent changes in the composition of the group o creating round-abouts, avoiding bottlenecks and dead ends o increasing the animal-to-feeding-place ratio o roughage ad libitum (in hay nets or in the form of straw), alternatively short feeding breaks (< 4 hours) o improve the accessibility of the drinking trough (positioning with round-about) and increase the flow rate (min. 8 l/min) o increase the space of the lying area with clean, hygienic, non-edible bedding o select non-slip, less abrasive flooring on main traffic routes and main staging areas o remove hazardous objects in horse areas (often at feeding facilities and on fences such as exposed coils and tension springs) o close dangerous openings (between 5-30 cm) as well as gaps that are open at the top The selected results exemplify that a holistic and comprehensive analysis of the housing conditions of horses is essential to make decisions for optimizing animal welfare of horses on a farm-by-farm basis.
