Subjective lameness evaluation during lungeing is routinely performed in equine practice, but its consistency remains limited, especially in cases of mild or complex asymmetry. This study aimed to assess the agreement between subjective gait evaluations and a markerless AI-based gait analysis system (OAI-MS) in traditional racehorses during lungeing. Intra- and inter-observer agreement of subjective evaluations was also investigated. 24 traditional racehorses were assessed during routine pre-race inspections (T0) while trotting on a soft surface. Two experienced equine clinicians independently evaluated each horse on both reins using the AAEP 0-5 scale; scores were then converted to a 3-level ordinal scale (0 = sound, 1 = mild, 2 = severe). Simultaneously, gait data were collected using the OAI-MS. A subset of 10 horses was re-evaluated after 10 days (T1) to assess short-term repeatability of the OAI-MS. Video-based reassessment (T2) was used to evaluate intra-observer agreement. Agreement was calculated using weighted Cohen's and Fleiss' kappa. p < 0.05. Inter-observer agreement ranged from κ = -0.20 to 0.36. Agreement between subjective evaluators and the OAI-MS ranged from slight to moderate (κ = 0.13-0.47). Intra-observer agreement was fair (κ ≈ 0.22), and OAI-MS repeatability reached κ = 0.43. Agreement was higher for forelimbs than hindlimbs. Most discrepancies were of low magnitude. Subjective gait evaluations during lungeing showed limited agreement. The OAI-MS demonstrated moderate repeatability, supporting its usability in the field and its potential role as a complementary tool in clinical decision-making, particularly when asymmetries are mild or disagreement occurs.

The occurrence of biotoxins and chemical residues in marketed horse feeds has direct influences on horse health but has not been studied yet. The study investigated the exposure and health implications of contaminants in various horse feedstuffs available on the European market. A total of 108 feed samples representing diverse product categories such as hay, processed roughage products, grains, and various supplementary feeds were collected from different European countries and analyzed for contaminants, including mycotoxins, phytoestrogens, pesticides, and veterinary drug residues using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Findings revealed that nearly all samples contained multiple fungal metabolites, with Fusarium toxins being the most prevalent. Processed roughage products (e.g., cobs, cubes, flakes and pellets) containing lucerne exhibited high concentrations of phytoestrogens and plant toxins compared to hay. The data also showed that supplementary feeds, particularly grain-based mueslis and mashes, were more prevalent sources of pesticide and veterinary drug residues than feed materials. Unusual substances in horse feed like colchicine and monensin, both highly toxic to horses, were also detected in roughly 10 to 20 % of the samples. However, our risk assesement suggests that the contamination of both compounds would not pose an acute health risk to horses. The study reveals the complexity of biotoxins and chemical residues and their potential risks in marketed equine feeds and underscores the critical need for targeted regulations, routine testing to ensure equine health and welfare.

Insemination of jennies with frozen-thawed donkey semen usually causes an intense uterine inflammation and results in low fertility. To evaluate the effects of seminal plasma on the time course of endometrial inflammation after insemination of jennies with donkey semen that was frozen using formamides as cryoprotective agents. Jennies were inseminated with fresh semen (FS, n = 14), frozen-thawed semen (FTS, n = 12) or frozen-thawed semen plus seminal plasma (FTS-SP, n = 13), and uterine cytology was evaluated at 8, 24 and 48 h post-insemination. At 8 h post-insemination the percentage of polymorphonuclear cells (%PMN) was higher (P < 0.05) in the FTS group (90.7 ± 4.6) than in the FS group (68.9 ± 4.3), while jennies in the FTS-SP had intermediate levels (82.7 ± 4.5). At 24 h the %PMN was higher (P < 0.05) in jennies in the FTS-SP group (84.8 ± 4.5) than in the other groups. However, a faster decline in %PMN from 24 h to 48 h post-insemination in the FTS-SP group resulted in no difference between groups at 48 h. All groups still had mean %PMNs above 50 % at 48 h post-insemination, but the females that became pregnant had faster clearance rates from 24 h to 48 h post-insemination, resulting in lower %PMNs (44.4 ± 3.8) than those in the non-pregnant jennies (64.8 ± 3.6) at 48 h post-insemination (P<0.05). Seminal plasma induced faster uterine polymorphonuclear clearance after 24 h post-insemination in jennies inseminated with frozen-thawed donkey semen, and this effect could be related to improved fertility.