[Changes in claw and leg health and hair cortisol concentration in dairy cows during the transition from tie-stall to free-stall housing - A study of a medium-sized farm]. / Veränderungen der Klauen- und Gliedmaßengesundheit sowie Haarkortisolkonzentration von Milchkühen bei der Umstellung von Anbinde- auf Laufstallhaltung.

OBJECTIVE: Claw health and carpal and tarsal lesions were assessed in a dairy herd during the transition from a tie-stall to a free-stall barn. The stress associated with the change in housing was also evaluated. MATERIALS AND METHODS: The initial size of the herd was 57 dairy cows, which were evaluated 4 times, 4-5 months apart, in a hoof-trimming chute. Claw horn and skin lesions of the foot were considered separately. The carpi and hocks were assessed for hair loss and skin lesions, and the hocks were also evaluated for swelling. Tail hair samples were collected from all cows during the second visit, and the cortisol concentration of 3 different sections of the hair was measured. RESULTS: The high prevalence of digital dermatitis and other skin lesions in the hind legs seen in the tie-stall barn (49 %) did not change significantly during the 14-month study period and was 46 % at the last visit. Heel horn erosions of the hind feet were rare in the tie-stall barn (14 %), but had a prevalence of 100 % at the end of the study. There was a trend for a decrease in the prevalence of other claw horn lesions. The prevalence and severity of carpal and hock lesions decreased significantly in the free-stall barn. Compared to values in cows at the tie-stall barn, the hair cortisol concentration was significantly higher during the transition period and at the free-stall barn. DISCUSSION AND CONCLUSIONS: The target variables were subjected to a multitude of factors but it can be assumed that the more comfortable lying surface in the free-stall barn had the most significant effect on carpal and tarsal joint health. The fluctuating prevalence of claw horn lesions indicates that claws health should be monitored closely. The increase in hair cortisol concentration after the transition to the free-stall barn could imply increased stress, but washout of cortisol in more distal hair segments could not be ruled out. CLINICAL RELEVANCE: The results of the present report cannot be directly applied to other herds; however, the significance of cow comfort is highlighted by the presence of fewer carpal and hock lesions. The significant increase in the prevalence of heel horn erosions indicates that the horn capsule is compromised under free-stall conditions.

Automatic detection of break-over phase onset in horses using hoof-mounted inertial measurement unit sensors.

A prolonged break-over phase might be an indication of a variety of musculoskeletal disorders and can be measured with optical motion capture (OMC) systems, inertial measurement units (IMUs) and force plates. The aim of this study was to present two algorithms for automatic detection of the break-over phase onset from the acceleration and angular velocity signals measured by hoof-mounted IMUs in walk and trot on a hard surface. The performance of these algorithms was evaluated by internal validation with an OMC system and a force plate separately. Seven Warmblood horses were equipped with two wireless IMUs which were attached to the lateral wall of the right front (RF) and hind (RH) hooves. Horses were walked and trotted over a force plate for internal validation while simultaneously the 3D position of three reflective markers, attached to lateral heel, lateral toe and lateral coronet of each hoof, were measured by six infrared cameras of an OMC system. The performance of the algorithms was evaluated by linear mixed model analysis. The acceleration algorithm was the most accurate with an accuracy between -9 and 23 ms and a precision around 24 ms (against OMC system), and an accuracy between -37 and 20 ms and a precision around 29 ms (against force plate), depending on gait and hoof. This algorithm seems promising for quantification of the break-over phase onset although the applicability for clinical purposes, such as lameness detection and evaluation of trimming and shoeing techniques, should be investigated more in-depth.

[Acute outbreak of lameness due to inflammatory claw disease in a beef herd]. / Akuter Ausbruch von Lahmheit infolge entzündlicher Klauenhauterkrankungen in einem Mastbetrieb.

INTRODUCTION: Several young bulls in a beef farm showed large, foul-smelling skin lesions in the plantar region of the coronary band and in the interdigital space. Some of the animals also had a painful, warm swelling in the palmar fetlock area. All bulls were lame (score 4/5), the most severely affected animal had a lameness score of 5/5. Initial local treatment was unsuccessful, therefore the animals received parenteral antimicrobial treatment leading to improvement of clinical signs and weight bearing in most animals. However, several animals were slaughtered prematurely due to severe foot lesions. The diverse clinical picture did not allow for diagnosing one specific claw affection without further diagnostic investigations. Histopathological and bacteriological examinations confirmed the diagnosis of digital dermatitis (DD) in combination with an interdigital phlegmon, whereby five of the seven examined specimens were positive for one or more Treponema spp. Treponemes belong to the spirochetes, the ones commonly involved in DD in dairy cows include Treponema medium, Treponema phagedenis and Treponema pedis. The last two species were detected in the present cases. The clinical findings and results of diagnostic investigations indicate that a severe form of DD complicated by a secondary infection and interdigital phlegmon caused an outbreak of severe lameness in young bulls in a beef farm. Single or combined claw diseases can be associated with severe losses not only in dairy but also in beef herds.

INTRODUCTION: Plusieurs jeunes taureaux dans une exploitation d'engraissement ont présenté, en particulier aux membres postérieurs, des lésions étendues et malodorantes au niveau plantaire de la couronne, qui s'étendaient jusqu'à l'espace interdigital. Certains animaux présentaient une enflure chaude et très douloureuse dans le pli du boulet. Les animaux étaient fortement boiteux (4/5), le taureau le plus atteint présentait une boiterie très sévère (5/5). Un traitement initial local a été mis en place, cependant, en l'absence de succès thérapeutique, les animaux ont été ensuite traités par voie parentérale avec un antibiotique, ce qui permis de réduire la sévérité du tableau clinique et d'améliorer la charge des membres atteints. En raison de la gravité des lésions, plusieurs animaux ont toutefois dû être abattus prématurément. Au vu de la diversité du tableau clinique, la maladie n'a pas pu être attribuée à une maladie des onglons particulière sans clarification supplémentaire du diagnostic. Un diagnostic de dermatite digitale en combinaison avec un phlegmon interdigital a été confirmé par l'analyse histopathologique ainsi que l'examen bactériologique: cinq des sept écouvillons examinés étaient positifs pour un ou plusieurs Treponema spp. Dans la famille des spirochètes, Treponema medium, Treponema phagedenis et Treponema pedis sont les tréponèmes le plus souvent impliqués dans la dermatite digitale chez les vaches laitières. Les deux germes mentionnés en dernier ont été mis en évidence dans les échantillons prélevés sur les taureaux d'engraissement décrits ici. L'image clinique et les résultats d'analyses des échantillons examinés suggèrent qu'une forme sévère de dermatite digitale compliquée par une infection secondaire et le développement d'un phlegmon interdigital s'est développée lors de l'épidémie de forte boiterie observée dans une exploitation d'engraissement. Les maladies des onglons, individuellement ou en combinaison, peuvent donc occasionner des pertes importantes dans les exploitations d'engraissement.

[Assessment of different pain management methods for the treatment of claw lesions in Meat Merino ewes]. / Bewertung verschiedener Methoden des Schmerzmanagements während der Behandlung von Klauenlederhaut-Läsionen bei weiblichen Merinofleischschafen.

OBJECTIVE: Pain management during veterinary procedures is a significant component of animal welfare and has legal as well as ethical implications. Even though regional intravenous anaesthesia (RIVA) is an accepted method for painful procedures involving the distal digits of sheep, this anaesthetic technique is rarely applied in the field. The primary goal was to investigate the feasibility, safety and efficacy of RIVA in sheep. A secondary goal was to examine whether the anaesthetic procedure can be improved by combining RIVA with sedation and whether these methods have a positive effect on the postoperative wellbeing of the animals. METHODS: A total of 36 Meat Merino sheep with contagious interdigital dermatitis and 12 healthy control sheep were used. Behaviour was observed during treatment of the lame sheep using various pain management protocols and during routine claw trimming of the healthy sheep, and all the sheep were observed after the procedures. The observed behaviours were assessed using scores and the scores compared among the animals of the 4 study groups (RIVA, sedation with xylazine hydrochloride + RIVA, placebo, control). RESULTS: RIVA was successfully conducted in sheep. Local reactions at the application sight and in the tourniquet area in 2 animals resolved completely. A significant reduction in defensive movements during the painful procedure confirmed the efficacy of RIVA. Stress-associated behaviours, including head shaking and idle chewing, occurred with a similar frequency in RIVA and placebo animals, leading to the conclusion that stress levels due to the handling in dorsal recumbency were comparable between these 2 groups. Sedation reduced the frequency of pain- and stress-associated behaviours, including guarding, favouring limbs, vocalisation, idle chewing and bruxism. Xylazine hydrochloride-RIVA animals displayed better weight-bearing in the affected limb, better food uptake and ruminated more postoperatively than sheep from the other study groups. CONCLUSION: RIVA in sheep is straightforward, safe and effective. Additional sedation reduces the stress and pain response. This pain and stress management has a positive effect on the postoperative wellbeing of sheep.

Are There Shared Mechanisms in the Pathophysiology of Different Clinical Forms of Laminitis and What Are the Implications for Prevention and Treatment?

Laminitis is a consequence of primary disease processes elsewhere in the body. The key pathophysiologic events are insulin dysregulation in endocrinopathic laminitis, ischemia in supporting limb laminitis, and inflammation in sepsis-related laminitis. These apparently disparate mechanisms converge to cause lamellar attachment failure through epithelial cell adhesion loss and stretch, possibly mediated by common growth factor signaling pathways. Tissue damage through mechanical distraction, inflammation, pain, and a proliferative epithelial healing response are features of acute laminitis regardless of the cause. Preventive and treatment strategies based on knowledge of these unique and common mechanistic events are likely to improve clinical outcomes.

Effects of induced weight shift in the hind limbs on claw loads in dairy cows.

The modern dairy industry is plagued by a high prevalence of claw horn lesions in cows, which cause lameness, affect well-being, limit milk production, and are responsible for premature removal of cows from the herd. The lateral hind claws are primarily affected, and this has been linked to a relatively higher load being exerted on the lateral claws when cows shift weight from one hind limb to the other. The vertical ground reaction forces and mean and maximum pressures under the claws were measured in 40 nonlame dairy cows before and during a shift in weight from one hind limb to the other, which was accomplished by applying pressure manually to one side of the pelvis. During square standing on firm ground, about two-thirds of the entire hind limb load was exerted on the 2 lateral claws, and the remaining one-third was exerted on the medial claws combined. At the moment of maximum weight shift, the lateral claw of the loaded limb bore almost two-thirds of the entire load of both hind limbs, with the heel zone bearing almost half of the load of both hind limbs. Subsequently, the load of the lateral claw of the contralateral hind limb decreased, as did the load of both medial claws. Thus, the weight redistribution had occurred predominantly between the lateral hind claws. The high load exerted on a lateral hind claw during weight shift and at maximum weight shift is assumed to play a role in the pathogenesis of claw horn lesions, particularly when accentuated by a softened claw horn and hard flooring.

Short communication: Use of lameness scoring to genetically improve claw health in Austrian Fleckvieh, Brown Swiss, and Holstein cattle.

The specific objective of this study was to evaluate the use of lameness scoring to genetically improve claw health in Austrian Fleckvieh, Brown Swiss, and Holstein cows based on data from the "Efficient Cow" project. In 2014, a 1-yr data collection was carried out. Data from 6,519 cows kept on 161 farms were recorded. At each time of milk recording, lameness scores were assessed by trained staff of the milk recording organizations. Hoof trimming on these farms was documented and recorded as well. Veterinarian diagnoses and culling due to foot and leg problems from these farms were available from the routine recording system. As repeated lameness records per cow and lactation were available, an overall lactation lameness score was calculated. Estimated heritabilities for lameness were 0.11, 0.05, and 0.09 for Fleckvieh, Brown Swiss, and Holstein, respectively; however, only heritability estimates for Fleckvieh were significantly different from zero. Breeding values for lameness were obtained, reversed in sign, and cows were ranked according to their breeding value. A low breeding value for lameness resistance (the bottom 10% of the cows) was associated with a significantly higher frequency of trimmed cows, which indicates that the cows selected by the farmer to be trimmed are not completely random. Additionally, a high breeding value for lameness resistance (the top 10% of the cows) was associated with lower frequencies of claw diseases recorded at trimming, claw and leg diagnoses, and culling due to foot and leg problems, which highlights the usefulness of lameness scoring for genetic improvement of claw health. Overall, selecting for a better lameness score has the potential to reduce claw diseases, especially the frequency of severe claw diseases that lead to culling.

Monitoring foot surface temperature using infrared thermal imaging for assessment of hoof health status in cattle: A review.

Detection of lameness early in cows is important from the animal welfare point of view and for reducing economic losses. Currently, many studies are being conducted for assessment of hoof health status by measuring the surface temperature of skin in cattle and other animal species in different parts of the world. Infrared Thermography (IRT) is able to detect lesions of hooves associated with lameness by measuring the changes in coronary band and hoof skin surface temperature. The surface temperature of a lame limb will be increased when the hoof has lesion(s). IRT has been used as a non-invasive diagnostic tool for early detection of hoof lesions based on the temperature difference between affected and non-affected hoof and maximum foot temperature on the regions of interest. In spite of having many potential applications in cattle production, factors affecting the temperature readings in thermograms must also are considered while taking images. Standard operating procedures must be established before taking thermographs under different circumstances, by considering all the factors that affect its normal function. IRT may help in minimising the cost of veterinary services, low yield, compromised fertility and culling expenses, where lameness cannot be resolved in early stages.

Paradigm shifts in understanding equine laminitis.

Laminitis, one of the most debilitating conditions of all equids, is now known to be the result of several systemic disease entities. This finding, together with other recent developments in the field of laminitis research, have provoked a rethink of our clinical and research strategies for this condition. First, laminitis is now considered to be a clinical syndrome associated with systemic disease (endocrine disease, sepsis or systemic inflammatory response syndrome, SIRS) or altered weight bearing rather than being a discrete disease entity. Next, laminitis associated with endocrine disease (endocrinopathic laminitis) is now believed to be the predominant form in animals presenting (primarily) for lameness. Third, the designation of laminitis as a primary and severe basement membrane pathology now requires revision. Instead, current data now proposes a variable subclinical phase associated with gross changes in the hoof capsule, with stretching and elongation of the lamellar cells an early and key event in the pathophysiology. These findings have fuelled new mechanistic hypotheses and research directions that will be discussed, together with their implications for future clinical management.

The impact of floor type on lameness and hoof health of dairy origin bulls.

This study aimed to evaluate the effect of using different floor types to accommodate growing and finishing beef cattle on lameness. In all, 80 dairy origin bulls were blocked according to live weight and breed into 20 groups, and randomly allocated within groups to one of four treatments. The floor types studied were fully slatted flooring throughout the entire experimental period (CS); fully slatted flooring covered with rubber strips throughout the entire experimental period (RS); fully slatted flooring during the growing period and then moved to a solid floor covered with straw bedding during the finishing period (CS-S) and fully slatted flooring during the growing period and then moved to fully slatted flooring covered with rubber strips during the finishing period (CS-RS). The total duration of the study was 204 days. The first 101 days was defined as the growing period, with the remainder of the study defined as the finishing period. During the growing period, there was a tendency for bulls accommodated on CS to have a higher locomotion score compared with those accommodated on RS (P=0.059). However, floor type had no significant effect on locomotion score during the finishing period. There was also no significant effect of floor type on digital dermatitis during both the growing or finishing period. Floor type had no significant effect on swelling at the leg joints at the end of the finishing period. Bulls accommodated on RS had the least probability of bruised soles during both the growing and finishing period (P<0.01). Growing bulls accommodated on CS had significantly greater front heel height net growth compared with those accommodated on RS (P<0.05). However, bulls accommodated on RS had a tendency to have greater front toe net growth compared with those accommodated on CS (P=0.087). Finishing bulls accommodated on CS-RS had the greatest front toe net growth (P<0.001). Heel height net growth was greatest in bulls accommodated on CS-S (P<0.001). Floor type had no significant effect on mean maximum hoof temperature during the growing period. Finishing bulls accommodated on CS-S had a significantly lower mean maximum hoof temperature compared with those accommodated on any other floor type (P<0.001). The study concluded that rubber flooring is a suitable alternative to fully slatted flooring, reducing the prevalence of bruised soles. Despite greater toe net growth in bulls accommodated on rubber flooring, there was no effect of floor type on locomotion score, suggesting that increased toe net growth does not adversely affect walking ability. In addition, although mean maximum hoof temperature was lowest in bulls accommodated on straw bedding, there was no evidence to suggest this is indicative of improved hoof health.

[Correlation of a lameness scoring system and claw lesion]. / Korrelation eines Lahmheit-Scoring- Systems und Klauenläsionen.

INTRODUCTION: The aim of this study was to investigate the relationship between lameness scoring and clinical findings. The lameness scoring and a gait assessment took place during drying off, the first week after calving and two months after calving in 29 lame and 27 free of lameness cows. In between the farmer scored the lamness. Most of the lameness occurred in the hind limbs and were most frequently caused by dermatitis digitalis, Mortellaro, Limax, and Rusterholz sole ulcer. The mean duration of lameness after treatment was 26 days (median 16 days) and was significantly longer in case of horn lesions than in skin lesions (including interdigital dermatitis). Lameness- free control animals were often affected by heel horn erosion and digital dermatitis. It was shown that the sensitivity of lameness (lameness is caused by a certain aetiology) for a certain cause of lameness (dermatitis interdigitalis, doble sole, purulent hollow wall, Limax, digital dermatitis, Rusterholz sole ulcer and sole contusion) increases along with the threshold (degree of lameness) but that the specificity (no lameness is not related to a certain aetiology) remained constant at the same time. The highest sensitivity was achieved in injuries, followed by interdigital hyperplasia. The receiver operating curve (ROC) showed that lameness was the best selecting symptom in white line lesions followed by claw injury. The positive predictive values varied between 38.8% in white line lesions and 0% in Rusterholz's sole ulcer. The negative predictive values varied between 99.1% in interdigital dermatitis and 82.3% in interdigital dermatitis. The ROC analysis shows which lameness is more related to a certain claw disease. The results demonstrate, that a lameness score cannot be linked to a certain claw disease.

INTRODUCTION: Le but de la présente étude était de voir dans quelle mesure il existe une relation entre un système de scoring des boiteries et les constatations cliniques. On a utilisé un scoring de boiterie simple et une estimation de la marche chez 29 animaux boiteux et 27 animaux sains au moment du tarissement, dans la première semaine après le vêlage ainsi que deux mois après celui-ci. Entre ces examens, les boiteries ont été enregistrées par les agriculteurs. La plupart des boiteries affectaient les postérieurs et étaient le plus souvent causées pas une dermatite digitée, une limace ou un ulcère de Rusterholz. La durée moyenne de la boiterie après traitement était de 26 jours (médiane 16 jours) et était nettement plus importante lors de lésions de la corne que lors de lésions de la peau. Les animaux non-boiteux étaient souvent atteints de pourriture de la corne en talons et de dermatite digitée. On a constaté que la sensitivité de la boiterie (la boiterie parle pour une cause donnée) augmentait avec l'augmentation de la valeur limite (intensité de la boiterie) pour une cause de boiterie donnée (dermatite interdigitée, double sole, fourmilière purulente, limace, dermatite digitée, ulcère de Rusterholz, contusion de sole) et que, simultanément, la spécificité (l'absence de boiterie parle contre une certaine cause) restait constante. La sensitivité la plus élevée était observée en cas de blessures, suivies par les limaces. La surface sous la courbe ROC (receiver operating curve) montrait que la discrimination était la meilleure en cas de fourmilière purulente, suivie par les blessures d'onglon. Les valeurs prédictives positives variaient entre 38.8% pour la fourmilière purulente et 0% pour l'ulcère de Rusterholz. Les valeurs prédictives négatives variaient entre 99.1% pour la dermatite interdigitée et 82.3% pour la dermatite digitée. L'analyse ROC montre quelles boiteries sont associées le plus souvent avec certaines affections des onglons. Les résultats montrent qu'on ne peut pas, sur la base de la boiterie, déduire l'affection des onglons.

[Claw infections in sheep - treatment options in veterinary practice, with special emphasis on ovine footrot treatment. - An update]. / Klaueninfektionen beim Schaf ­ Therapiemöglichkeiten in der tierärztlichen Praxis unter besonderer Berück sichtigung der Moderhinkebekämpfung.

Infectious causes of lameness in sheep remain of considerable clinical importance. Because of the availability of newly licensed drugs, important changes in therapy options, particularly for ovine footrot, have occurred. This paper provides an overview of common and rarer infectious causes of lameness in sheep, and presents a detailed review of recent advances in research regarding the aetiology, diagnosis, prevention, treatment and control of ovine foot rot. Despite the recent release of several antibiotics licensed for the treatment of footrot in sheep, the use of footbaths following the cascade of regulations remains a crucial part of many integrated treatment and control programmes. The sustainable control of foot rot requires recent advances in science to be put into practice, with tailor-made control programmes for each individual farm. The article presents various treatment options and potential routes of control and eradication.

Effect of hoof trimmer intervention in moderately lame cows on lameness progression and milk yield.

The objective of this study was to evaluate the effect of hoof trimmer intervention (HTI) in moderately lame cows on lameness progression and milk yield. Two freestall Holstein herds were enrolled. Cows were milked 2 (herd A: 2,374 cows) or 3 (herd B: 2,800 cows) times a day. Within each dairy, moderately lame cows [locomotion score (LS) = 3 on a 5-point scale] were randomly assigned to control group (CON; herd A = 66, herd B = 84) or treatment group (HTI; evaluated and treated by the hoof trimmer under researchers' supervision; herd A = 73; herd B = 75). Enrollment criteria were <350 d in milk, <180 d pregnant, >10 kg/d of milk yield, not selected for therapeutic trimming 2 mo before enrollment, and >14 observations of daily milk yield during the study period. Biweekly lameness scoring (LS ≤2, LS = 3, LS ≥4) was conducted up to 6 wk post-intervention. Lesion type and severity records were collected at intervention from HTI cows and up to 6 wk post-intervention from all enrolled cows identified as lame by farm employees. Daily milk yield data were collected from -1 to 6 wk relative to intervention using Afifarm (Afimilk Ltd., Kibbutz Afikim, Israel) records. No treatment effect was detected on the predicted probability of locomotion score, but the predicted probability of LS ≥3 decreased over time in herd B, whereas in herd A, it initially decreased but later increased. A tendency for a treatment by time interaction was observed in herd A; at 2 wk post-intervention, the predicted probability for LS ≥3 was higher for HTI (0.69) than for CON (0.43), but similar at 4 wk (0.41 HTI, 0.49 CON) and 6 wk (0.77 HTI, 0.73 CON). At intervention, most study cows had no lesions (41.2%), sole hemorrhages (28.4%), thin soles (8.8%), or vertical fissure (6.8%). During the 6 wk following intervention, a similar proportion of cows were identified as lame in CON (8.7%) and HTI (6.7%) groups. In herd A, milk yield (least squares means ± standard error) was similar for CON (42.0 ± 0.77 kg/d) and HTI (42.3 ± 0.75 kg/d) cows, whereas in herd B, it tended to be lower for HTI (43.7 ± 0.61 kg/d) than for CON (45.2 ± 0.59 kg/d) cows. A significant effect of time was detected on both dairies, with milk yield decreasing over the study period. In our study, implementing HTI on moderately lame cows resulted in no improvement in gait or milk yield. The low presence of severe lesions amenable to therapy may partially explain our findings.

Effect of claw horn lesion type and severity at the time of treatment on outcome of lameness in dairy cows.

Prompt diagnosis and treatment of claw horn lesions in cattle affects the likelihood of recovery; however, it is unknown if the type of lesion influences the likelihood of recovery. The aim of this study was to investigate whether the type, severity and frequency of claw horn lesions in newly lame cows (lame for no more than 2 weeks) at the time of corrective foot trimming affects the probability of recovery from lameness after treatment. The images of 112 feet (224 claws) from newly lame cows (n=112; lame in only one hind foot), which were treated with a standardised therapeutic hoof trim only, were used to score claw horn lesions (sole ulcer, sole haemorrhage, white line haemorrhage or white line separation). Most cows (n=107/112; 95.5%) were classified as mildly lame at the time of treatment. The proportion of cows that recovered 2 weeks after therapeutic hoof trimming was 88/112 (78.6%). Results of a multilevel logistic regression model indicated that severely lame cows were less likely to recover than those that were mildly lame (odds ratio, OR, 0.16; P=0.04). White line haemorrhage had a significant negative impact on the likelihood of recovery from lameness (OR 0.14; P>0.01); however, recovery of cows with white line haemorrhage was positively associated with the length of the lesion (OR 1.05; P=0.03). This latter finding may be associated with the severity of the lesion, since mild claw horn lesions affected a significantly larger area of the claw than more severe lesions. The length and type of claw horn lesion were associated with recovery from lameness.

Dairy cows change locomotion score and sensitivity to pain with trimming and infectious or non-infectious lesions.

Lameness can negatively affect production, but there is still controversy about the perception of pain in dairy cows. This study aimed to verify the effects of hoof affections in dairy cows on locomotion score, physiological attributes, pressure nociceptive threshold, and thermographic variables, as well as assess improvement on these variables after corrective trimming and treatment. Thirty-four lame lactating cows were gait-scored, and all cows with locomotion score ≥4 were retained for this study 1 day before trimming. Lame cows were diagnosed, pressure nociceptive threshold at sound, and affected hooves were measured, thermographic images were recorded, and physiological attributes were evaluated. Hooves with lesions were trimmed and treated and cows were re-evaluated 1 week after such procedures. The experimental design was a completely randomized design. Each cow was considered an experimental unit and traits were analyzed using paired t test, linear correlation, and linear regression. Digital and interdigital dermatitis were classified as infectious diseases while laminitis sequels, sole ulcers, and white line were classified as non-infectious diseases. After 1 week, the locomotion score was reduced on average in 1.5 points. Trimming increased the pressure nociceptive threshold for cows with non-infectious affections while tended to increase the pressure nociceptive threshold for cows with infectious affections. Physiological attributes and thermographic values did not change with trimming. Trimming and treatment have benefic effects on animal welfare as gait is improved and sensitivity to pain is reduced.

A novel model to assess lamellar signaling relevant to preferential weight bearing in the horse.

Supporting limb laminitis (SLL) is a devastating sequela to severe unilateral lameness in equine patients. The manifestation of SLL, which usually only affects one limb, is unpredictable and the etiology is unknown. A novel, non-painful preferential weight bearing model designed to mimic the effects of severe unilateral forelimb lameness was developed to assess lamellar signaling events in the supporting limb (SL). A custom v-shaped insert was attached to the shoe of one forelimb to prevent normal weight bearing and redistribute weight onto the SL. Testing of the insert using a custom scale platform built into the floor of stocks confirmed increased distribution of weight on the SL compared with the unloaded forelimb (UL) and the contralateral (CH) and ipsilateral (IH) hind limbs in six Standardbred horses. In a second part of the study, eight healthy Standardbred horses were fitted with the insert and tied with consistent monitoring and free access to hay and water for 48 h, after which the lamellae were harvested. Real-time qPCR was performed to assess lamellar mRNA concentrations of inflammatory genes and immunoblotting and immunofluorescence were performed to assess lamellar protein concentration and cellular localization of hypoxia-related proteins, respectively. Lamellar mRNA concentrations of inflammatory signaling proteins did not differ between SL and either CH or IH samples. HIF-1α concentrations were greater (P < 0.05) in the SL compared to the CH. This work establishes an experimental model to study preferential weight bearing and initial results suggest that lamellar hypoxia may occur in the SL.

Hypergravity within a critical period impacts on the maturation of somatosensory cortical maps and their potential for use-dependent plasticity in the adult.

We investigated experience-dependent plasticity of somatosensory maps in rat S1 cortex during early development. We analyzed both short- and long-term effects of exposure to 2G hypergravity (HG) during the first 3 postnatal weeks on forepaw representations. We also examined the potential of adult somatosensory maps for experience-dependent plasticity after early HG rearing. At postnatal day 22, HG was found to induce an enlargement of cortical zones driven by nail displacements and a contraction of skin sectors of the forepaw map. In these remaining zones serving the skin, neurons displayed expanded glabrous skin receptive fields (RFs). HG also induced a bias in the directional sensitivity of neuronal responses to nail displacement. HG-induced map changes were still found after 16 wk of housing in normogravity (NG). However, the glabrous skin RFs recorded in HG rats decreased to values similar to that of NG rats, as early as the end of the first week of housing in NG. Moreover, the expansion of the glabrous skin area and decrease in RF size normally induced in adults by an enriched environment (EE) did not occur in the HG rats, even after 16 wk of EE housing in NG. Our findings reveal that early postnatal experience critically and durably shapes S1 forepaw maps and limits their potential to be modified by novel experience in adulthood.

Early detection and treatment of lame cows. Effect on duration and prevalence of lesion-specific lameness.

OBJECTIVE: The aim of this study was to investigate the impact of specific hoof lesions on the locomotion score (LS) as well as the effect of early detection and treatment on duration and prevalence of lesion-specific lameness. MATERIAL AND METHODS: In a dairy herd in Lower Saxony, Germany, with 144 lactating cows, claw trimming was performed by a professional claw trimmer at the beginning and the end of a 41-week trial period. Weekly a veterinarian assessed the LS according to Sprecher et al. (1997) in 99 cows. The front and hind claws of cows with an LS > 1 were examined and treated within 5 days. For individual diagnoses, the duration of lameness was calculated as the number of weeks from first treatment until recovery (LS = 1). RESULTS: In total, 580 examinations and treatments were performed on 94 cows. There were 189 new lameness cases with a total of 290 diagnoses. At the first treatment, 81.0% of the cows displayed an LS of 2. Cows with digital dermatitis (DD), heel horn erosion and white line disease (WLD) more often had an LS > 2 compared to cows with Rusterholz' sole ulcer, interdigital hyperplasia or inadequate claw length/posture (p < 0.05). Cows with only one affected leg, more often had an LS > 2 than cows with several affected legs (p < 0.1). Lameness caused by WLD and arthritis/periarthritis remained for the longest time period. The prevalence of sole haemorrhages and/or double soles, WLD, interdigital dermatitis and interdigital hyperplasia decreased significantly during the test period. Prevalence of sole ulcer (sole ulcer and Rusterholz' sole ulcer) and DD remained unaffected. CONCLUSION AND CLINICAL RELEVANCE: Locomotion score was affected by the type of claw/limb disorder and the number of diseased limbs. Regular locomotion scoring and continuous treatment of cows with an LS > 1 is associated with a decrease in the prevalence of several claw lesions. Therefore, prevalence of severe claw lesions like WLD, which was associated with a long duration of lameness, can be reduced. In contrast, for decreasing prevalence of digital dermatitis more than weekly treatment of every cow with LS > 1 is required. Preventive measures like footbaths or improved hygiene should accompany the individual animal treatment.

Models for genetic evaluations of claw health traits in Spanish dairy cattle.

Genetic parameters of 7 claw health traits from Spanish dairy cattle were estimated and the predictive ability of linear and ordinal threshold models were compared and assessed. This study included data on interdigital and digital dermatitis (DE), sole ulcer (SU), white line disease (WL), interdigital hyperplasia (IH), interdigital phlegmon (IP), and chronic laminitis (CL) collected between July 2012 and June 2013 from 834 dairy herds visited by 21 trained trimmers. An overall claw disorder (OCD) was also considered an indicator the absence or the presence of at least 1 of the 6 disorders. Claw health traits were scored as categorical traits with 3 degrees of severity (nonaffected, mild, and severe disorder). Genetic parameters were estimated by fitting both a standard linear model and an ordinal threshold animal model. Around 21% of cows had at least 1 claw disorder, and the most frequent disorders were SU, DE, WL, and CL. Heritabilities of claw disorders estimated with a linear model ranged from 0.01 (IP) to 0.05 (OCD), whereas estimates from the ordinal threshold models ranged from 0.06 to 0.39 (for IP and IH, respectively). Repeatabilities of claw health estimated with the linear model varied from 0.03 to 0.18 and estimates with the ordinal threshold model ranged from 0.33 to 0.69. The global trait OCD was correlated with all disorders, except for IH and IP when the linear model was fitted. Two different genetic backgrounds of claw disorders were found. Digital dermatitis showed positive correlations with IH and IP, whereas SU was positively correlated with WL and CL. The predictive ability of the models was assessed using mean squared error and Pearson correlation between the real observation and the corresponding prediction using cross-validation. Regardless of the claw health status, the linear model led to smaller mean squared error. However, differences in predictive ability were found when predicting nonaffected and affected animals. For most traits, healthy cows were better predicted using the threshold model, whereas the linear model fitted affected cows better. Correlations between the observed data and corresponding predictions support those results ranging from 0.01 to 0.34. Claw health traits showed enough genetic variance to be included in the selection goal for Spanish Holsteins to select animals with less susceptibility to claw health problems, and we suggest the linear model for implementing genetic evaluations of claw heath traits.

Effectiveness of salicylic acid paste for treatment of digital dermatitis in dairy cows compared with tetracycline spray and hydrotherapy.

The effectiveness of salicylic acid paste (PASTE) was tested for topical treatment of 25 acute and 25 chronic digital dermatitis (DD) lesions. Control groups with the same number of acute and chronic DD lesions were treated with topical oxytetracycline spray (SPRAY) and by washing only with water (HYDRO) respectively. The therapeutic effects were evaluated using a pain score, the healing rate, the lesion size and other parameters. Pre-treatment and control examinations were carried out on day 0, 4, 14 and 21. In the PASTE group, 76.0% of acute DD lesions were pain free and 64.0% of acute DD lesions were healed on day 21 showing a normal skin surface (MO). Only 28.0% of acute DD lesions treated with SPRAY and 16.0% treated with HYDRO had healed on day 21. A significantly higher healing rate was revealed in acute lesions for the PASTE compared to the HYDRO group (p < 0.05) for all three re-checks, and for the PASTE group compared with the SPRAY group (p < 0.05) for day 4 and day 14. Healing rates of chronic DD lesions were higher in the PASTE group with 44.0% on day 14 and 36.0% on day 21, compared with 16.0% in the SPRAY and 32.0% in the HYDRO group on day 14, and 20.0% (SPRAY) and 28.0% (HYDRO) on day 21 respectively. The recurrence rate of lesions after they had healed during the study period was 14.5% in total. Digital dermatitis lesions treated with salicylic acid paste and a wrap showed significantly higher healing rates within the study period, odds ratios for healing of acute lesions with PASTE were 4.5 to 6.7 times higher than with SPRAY, and 9.3 to 36.4 higher compared with HYDRO.