From summer 2018 to summer 2019, several Thoroughbred racehorses held at the Miho Training Centre of the Japan Racing Association inadvertently ingested excessive amounts of sodium selenite, resulting in typical chronic selenium (Se) poisoning - the so-called alkali disease. The typical abnormality was a hoof wall disorder with a circumferentially deep ring and/or transverse hoof wall cracks parallel to the coronet on all feet and appearing after excessive ingestion. One affected Thoroughbred male was unique in that all the hooves had a rough surface with a very fragile hoof wall, but no wall rings or transverse cracking. This horse was euthanized because of dysstasia due to the permanent foot pain associated with hoof wall deformities in the front feet. To detect Se deposition in the hooves, we used energy-dispersive X-ray fluorescence (EDXRF) analysis to measure the Se signal intensity of each lesion. Characteristic Se-kα signals were emitted from the areas of histologically damaged hoof wall at 33.76 ± 11.78 (mean ± SD) counts per second (cps)/mm2. In contrast, the signal from the uninjured proximal hoof wall was 1.43 ± 0.14 cps/mm2 and that from the uninjured distal hoof wall was 1.51 ± 0.23 cps/mm2. The much greater Se deposition in the injured hoof walls suggests that their disintegration was caused by alkali disease. These results indicate that atypical hoof wall abnormalities due to alkali disease can be diagnosed by EDXRF analysis.

Zebu cattle (Bos indicus) is reported to be more resistant towards harmful environmental factors than taurine cattle (Bos taurus). A few hundred zebu cattle are kept in Switzerland and in contrast to the Swiss indigenous breeds, infectious hoof disease in zebu is not observed. Therefore, we compared the prevalence of three ruminant hoof pathogens in zebu and taurine cattle. These included Treponema spp., Fusobacterium necrophorum and Dichelobacter nodosus which are associated with bovine digital dermatitis (BDD), different bovine hoof diseases and ovine footrot, respectively. Interdigital swabs and punch biopsies from hind feet of slaughter animals were tested for the three pathogens by PCR. Sixty zebu from eight farms were compared to a convenience sample of 20 taurine cattle from 17 farms. Treponema spp. associated with BDD were not detected in zebu while 23 % of animals and 50 % of farms were positive for benign D. nodosus, with results indicating environmental contamination rather than colonization. Taurine cattle showed 35 % of animals and 41 % of farms positive for T. phagedenis while 90 % of animals and 94 % of farms were colonized by D. nodosus as indicated by a 500-fold higher bacterial load than in zebu. The difference in prevalence of the two pathogens between zebu and taurine cattle was highly significant. F. necrophorum was as well only detected in taurine cattle with values of 15 % of animals and 17.7 % of farms, being significantly different at the animal level. Furthermore, genetic analysis of Swiss zebu indicates high genomic diversity and clear separation from taurine cattle. This is the first evidence that zebu show resistance towards colonization by bacterial hoof pathogens in contrast to taurine cattle.

Many studies have shown a strong correlation between Hindgut Acidosis (HGA) and the occurrence of laminitis in horses; therefore, the early diagnosis of HGA is essential. In this study, we investigated changes in the plasma concentrations of lipopolysaccharide-binding protein (LBP) and serum amyloid A (SAA) as inflammatory markers in horses with laminitis. Sixteen healthy male Arabian horses that had cecal cannulation without visible laminitis or general symptoms were randomly divided into two groups. The horses were fed two different diets in a forage-to-concentrate ratio. Blood samples were collected on Days 1, 10, and 20. The primary objective of this study was to analyze plasma levels of LBP and SAA. Cecal specimens were obtained from each equine subject on three designated days: days 1, 10, and 20. The second objective was to assess the levels of pH and volatile fatty acids (VFA) in the samples. Throughout the study period, horses fed a high-concentrate diet exhibited a significantly elevated average lameness grade on days 10 and 20 compared to the initial stage (P < 0.001). On day 20, a significant increase in the concentration of SAA was observed in horses fed a high-concentrate diet, in contrast to the initial stage of the study. LBP levels in the plasma were significantly elevated on days 10 and 20 in horses fed a high-concentrate diet. Based on our findings, it is recommended that the evaluation of plasma LBP concentrations is more effective than SAA for the early identification of HGA in horses fed a high-grain diet.

BACKGROUND: Cattle lameness is a significant welfare and economic problem facing the livestock industry. Published research has investigated foot trimming practices in dairy herds, but little is known about the practices in beef herds. Therefore, the objective of this study was to obtain information about the current practices of professional cattle foot trimmers concerning beef cattle within the UK.
METHODS: An online survey comprising 16 questions was created using the Joint Information Systems Committee platform. The survey was open for 3 months.
RESULTS: There was a significant difference (p < 0.05) between the proportions of dairy cattle and beef cattle receiving preventative foot trims. Digital dermatitis was the most commonly recorded cause of lameness when a lame beef animal was trimmed by the respondents, followed by white line disease. A thematic analysis of foot trimmers\' opinions of barriers to engagement on beef farms is presented, in addition to their opinions on veterinary involvement with beef lameness.
CONCLUSIONS: Distribution bias may have affected the results, as the survey was distributed online with support from the Cattle Hoof Care Standards Board and the National Association of Cattle Hoof Trimmers. The percentage of foot trimmers not affiliated with either professional body is not known.
CONCLUSIONS: Further research on the impact of lameness on suckler and finishing cattle, including investigations into preventative actions to reduce lameness in beef systems, is warranted.

In this study, the accuracy of using 3D measurements from a 3D image creation application (3DICA) as a potential tool for measuring hoof dimensions in cattle was determined. Fifty distal limbs of cattle obtained from a slaughterhouse were included after the data was trimmed by the functional hoof trimming method. The lengths of six dimensional variables determined by manual measurements served as the true values. Then, the images of these hooves were captured with the 3DICA, and the same variables were determined by the measurement function in the 3DICA. A strong positive correlation was obtained between the 3D and manual measurements for five of the six points, and the mean difference was within 2 mm at all six points. However, the limits of agreement varied at three of the six points. In conclusion, compared with manual measurements, the 3D measurements provided approximately equivalent measurements for the hoof dimensions. However, these findings are preliminary, and further investigations are needed.

The equine hoof wall has outstanding impact resistance, which enables high-velocity gallop over hard terrain with minimum damage. To better understand its viscoelastic behavior, complex moduli were determined using two complementary techniques: conventional (∼5 mm length scale) and nano (∼1 µm length scale) dynamic mechanical analysis (DMA). The evolution of their magnitudes was measured for two hydration conditions: fully hydrated and ambient. The storage modulus of the ambient hoof wall was approximately 400 MPa in macro-scale experiments, decreasing to ∼250 MPa with hydration. In contrast, the loss tangent decreased for both hydrated (∼0.1-0.07) and ambient (∼0.04-0.01) conditions, over the frequency range of 1-10 Hz. Nano-DMA indentation tests conducted up to 200 Hz showed little frequency dependence beyond 10 Hz. The loss tangent of tubular regions showed more hydration sensitivity than in intertubular regions, but no significant difference in storage modulus was observed. Loss tangent and effective stiffness were higher in indentations for both hydration levels. This behavior is attributed to the hoof wall\'s hierarchical structure, which has porosity, functionally graded aspects, and material interfaces that are not captured at the scale of indentation. The hoof wall\'s viscoelasticity characterized in this work has implications for the design of bioinspired impact-resistant materials and structures. STATEMENT OF SIGNIFICANCE: The outer wall of horse hooves evolved to withstand heavy impacts during gallop. While previous studies have measured the properties of the hoof wall in slowly changing conditions, we wanted to quantify its behavior using experiments that replicate the quickly changing forces of impact. Since the hoof wall\'s structure is complex and contributes to its overall performance, smaller scale experiments were also performed. The behavior of the hoof wall was within the range of other biological materials and polymers. When hydrated, it becomes softer and can dissipate more energy. This work improves our understanding of the hoof\'s function and allows for more accurate simulations that can account for different impact speeds.

Understanding the aetiology and pathogenesis of claw-horn disease (CHD) is essential for developing prevention/treatment programmes. Haemorrhages in the hoof horn (i.e. white line/sole haemorrhages) are an important part of the pathogenesis of CHD, being precursors to and predictors of lesions such as white-line disease and sole ulcer. Understanding haemorrhage development can provide useful information about the aetiology and pathogenesis of CHD. The development of hoof horn haemorrhages is best studied in cattle without previous claw-horn damage, as previous history of damage can markedly alter the hoof\'s response to stressors. Since the early 1990s, many prospective studies of the risk factors associated with CHD have been undertaken in late pregnant and early lactation heifers, which have a low risk of having had CHD but which are exposed to the same risk factors as lactating cows. Those studies have used a range of methods to assess hoof horn haemorrhages, with the principal focus, particularly initially (but also more recently), being on measuring lesion severity. However, as the science developed it became clear that measuring lesion extent was also important and that combining severity and extent in a single measure was the best approach to assess hoof horn haemorrhages. Studies of hoof horn haemorrhage in heifers have significantly increased our understanding of CHD, demonstrating the importance of housing and the relative lack of importance of post-calving nutrition. Most importantly, they have shown the importance of parturition as a risk factor for CHD, and how parturition interacts with other risk factors to accentuate their effect. The use of such studies has decreased in recent years, despite recent research showing that we still have much to learn from prospective studies of hoof horn haemorrhages in heifers.

BACKGROUND: Digital dermatitis (DD) is a contagious bovine foot disease causing reduced animal welfare and negative economic consequences for the farmer. Treponema spp. are the most important causative agents. Studies indicate that trimming equipment can transfer DD-associated treponemes between cows. The aim of this observational study in 22 DD-positive Norwegian dairy herds was to investigate the risk of transferring Treponema spp. with trimming equipment and chutes after claw trimming, and after washing and disinfection. Swabs from the trimming equipment and chutes were collected from nine different locations, at five different time points. Bacterial DNA was extracted from 647 swabs and analysed by qPCR for Treponema spp. In addition, 172 swabs taken immediately after trimming, were analysed by a multiplex qPCR targeting T. phagedenis, T. pedis and T. medium/vincentii. Biopsy sampling from DD lesions was performed on cows in the same herds during trimming. Altogether 109 biopsies were analysed by FISH for confirmation of the DD diagnosis and identification of Treponema phylotypes (PTs).
RESULTS: High numbers of Treponema spp. were detected from all nine locations on the trimming equipment and chutes immediately after trimming, and T. phagedenis was detected on two or more locations in all but two herds, 1 and 19. There was a decline in the amount of Treponema spp. after washing and disinfection. The belly belt, the cuff, and the footrest on the chute had the highest proportion of positive samples after disinfection. The belly belt had the highest copy numbers of all nine locations (median = 7.9, max = 545.1). No Treponema spp. was detected on the hoof knives after disinfection. Treponema phagedenis, T. pedis, and Treponema phylotype 3 (T. refringens) were detected by FISH analysis of the biopsies. Treponema phagedenis was detected in biopsies from all herds except 1 and 19.
CONCLUSIONS: This study shows that DD-associated Treponema spp. were present on the trimming equipment and chutes after trimming cows in DD-positive herds. Washing and disinfection reduced the load of Treponema spp. However, large differences in Treponema spp. between different locations were documented. High copy numbers on the grinder and the chute after disinfection, indicates that sufficient cleaning and disinfection of these locations is difficult, and that passive transfer of DD-associated treponemes (viable or not) is possible.

UNASSIGNED: Underrun heels are among the most hoof imbalances, causing poor performance in hoses. Several corrective shoeing protocols have been performed, but the outcomes have yet to be consistent. In this study, we proposed an alternative trimming protocol for managing underrun heels: strategic palmar trimming before conventional shoeing. Therefore, the current study aimed to investigate the potential of strategic palmar trimming before conventional shoeing for managing hoof imbalance in horses with underrun heels.
UNASSIGNED: Eleven affected horses were divided into control (5 horses with 14 defective hooves) and experimental (6 horses with 16 defective hooves) groups. The experimental group underwent strategic palmar trimming before conventional shoeing, while the control horses received regular trimming before traditional shoeing. Dorsal hoof wall angle (DHWA)/heel angle (HA) ratios, heel-bulb distance, and six parallel lines indicating solar surface dimension were determined before, and after 5, 10, 15, 20, 25, and 30 weeks of the different trimming protocols. Palmar trimming distance was only measured in experimental horses.
UNASSIGNED: A group-by-time interaction was observed for DHWA/HA ratios and solar surface dimension. Separate effects for group and time were observed in the heel-bulb distance. A modification in hoof conformation was detected at 25-30 weeks only in horses in the experimental group, including decreases in DHWA/HA ratio, heel-bulb distance, and palmar trimming distance, coinciding with an increase in palmar width of trimmed hooves.
UNASSIGNED: Different trimming protocols produced a different effect on hoof conformation. Therefore, tactical remedial trimming can potentially control poor hoof conformation in horses with underrun heels.

The control of digital dermatitis (DD) among cattle is crucial; however, effective and environmentally-sound control measures have yet to be identified. From the monitoring data of DD which were recorded during regular hoof trimmings in a farm in Hokkaido, Japan, we detected a decrease in the DD prevalence in a herd where an anaerobic bacterial fermentation enhancer (ABFE) was distributed. The possible effect of ABFE was analyzed using a retrospective repeated cross-sectional design. The prevalence of DD decreased over time in the ABFE-distributed group. Furthermore, a selected regression model indicated the time-dependent enhancement of the decreasing trend. While potential coincidental factors may influence, this study provides a basis for further research on the preventive effect of ABFE against DD.