Genome-wide association and functional genomic analyses for various hoof health traits in North American Holstein cattle.

Hoof diseases are a major welfare and economic issue in the global dairy cattle production industry, which can be minimized through improved management and breeding practices. Optimal genetic improvement of hoof health could benefit from a deep understanding of the genetic background and biological underpinning of indicators of hoof health. Therefore, the primary objectives of this study were to perform genome-wide association studies, using imputed high-density genetic markers data from North American Holstein cattle, for 8 hoof-related traits: digital dermatitis, sole ulcer, sole hemorrhage, white line lesion, heel horn erosion, interdigital dermatitis, interdigital hyperplasia, and toe ulcer, and a hoof health index. De-regressed estimated breeding values from 25,580 Holstein animals were used as pseudo-phenotypes for the association analyses. The genomic quality control, genotype phasing, and genotype imputation were performed using the PLINK (version 1.9), Eagle (version 2.4.1), and Minimac4 software, respectively. The functional genomic analyses were performed using the GALLO R package and the DAVID platform. We identified 22, 34, 14, 22, 28, 33, 24, 43, and 15 significant markers for digital dermatitis, heel horn erosion, interdigital dermatitis, interdigital hyperplasia, sole hemorrhage, sole ulcer, toe ulcer, white line lesion disease, and the hoof health index, respectively. The significant markers were located across all autosomes, except BTA10, BTA12, BTA20, BTA26, BTA27, and BTA28. Moreover, the genomic regions identified overlap with various previously reported quantitative trait loci for exterior, health, meat and carcass, milk, production, and reproduction traits. The enrichment analyses identified 44 significant gene ontology terms. These enriched genomic regions harbor various candidate genes previously associated with bone development, metabolism, and infectious and immunological diseases. These findings indicate that hoof health traits are highly polygenic and influenced by a wide range of biological processes.

Development by design of experiment and validation of a HPLC-UV method for simultaneous quantification of 1-nitro-2-phenylethane and methyleugenol: Application to nail permeation/retention studies.

Aniba canelilla (Kunth) Mez is an aromatic tree from Amazon region whose essential oil presents 1-nitro-2-phenylethane (NP) and methyleugenol (ME) as major compounds. Several properties are attributed to Aniba canelilla essential oil (ACEO), such as antifungal. Onychomycoses are fungal nail infections that require novel therapeutic alternatives, especially topical ones. However, to ensure the success of topical therapy, the active compound should be able to penetrate/permeate the nail plate, which is challenging due to the highly keratinized composition of this structure. Thus, the aims of this article were to develop, validate and apply a high-performance liquid chromatography method (HPLC-UV) to quantify NP and ME in porcine hoof extract (PHE) and receptor fluid (RF) during in vitro permeation/retention studies in nail model, for which porcine hoof membranes were used. For method development, two Designs of Experiment (DoE) were adopted: 23 Full Factorial and Box-Behnken. Retention times of 5.65 and 7.49 min were achieved for NP and ME, respectively. The method was full validated for NP and ME quantification in receptor fluid, in accordance with the recommended parameters by ICH Q2(R1) Guideline. In addition, the method was full validated for NP and ME quantification in porcine hoof extract, considering the parameters and criteria of ICH M10 Guideline. In vitro permeation/retention studies were carried out in nail model, and promising results were obtained. NP reached the receptor fluid in the order of 441.1 ± 92.1 µg/cm2 at 72 h. The amount of NP and ME retained into porcine hoof membrane was 1272.6 ± 225.7 µg/cm2 and 84.7 ± 20.4 µg/cm2, respectively, at 72 h. Our findings open perspective to develop topical formulations containing ACEO as active compound aiming the management of onychomycosis.

Immediate Effect of Hoof Trimming on Hoof and Thoracic Joint Angles in Mangalarga Mares.

It is important to understand the effects of hoof trimming on hoof and limb conformation to maximize its benefits on the health of the appendicular skeleton of horses, thus promoting improvements in athletic performance and sporting longevity with regard to athletic horses. There is little information on possible changes in the angulation of the thoracic limb joints after hoof trimming and correlations between the angulation of the thoracic limb joints with hoof measurements. To that purpose, nineteen Mangalarga mares received routine hoof trimming. Visual recordings (photographs) were taken before and after the procedure. Differences (p < 0.05) were found in hoof length, toe angle, heel angle, medial heel height, and metacarpophalangeal angle. Before trimming, correlations were found between frog length and scapulohumeral angle (SH) (r = -0.457; p = 0.049), and between toe length and shoulder-ground angle (SG) (r = -0.553; p = 0.049). A correlation was also seen between the distance from the frog to the lateral wall and the SH angle (r = 0.690; p = 0.001). After trimming, there was a correlation between humeroradial (HR) and SH joint angles (r = 0.669; p = 0.002), and the SG and SH angles (r = 0.488; p = 0.034). This study showed an immediate effect of trimming on the toe angle and heel angle and on the metacarpophalangeal joint angle, in addition to correlations between the hoof and proximal joint angles, following trimming, thus evidencing the relevance of trimming not only in hoof morphology, but also in the conformation of the appendicular skeleton of horses.

Transmural Ultrasonography in the Evaluation of Horse Hoof Internal Structures: Comparative Quantitative Findings-Part 2.

The transmural ultrasound allows for the definition of the normal appearance of the hoof tissues and internal structures. Determining such measurements and proportions could contribute to evaluations of the normal spatial distal phalanx-hoof relationship. The objective was to describe the hoof's dermis and epidermis measurements using the transmural technique, in comparison with DR and anatomical sections. Sixty-two healthy hooves without digital radiographic abnormalities, made up of 30 anatomical pieces (phase 1) and 32 alive horse hooves (phase 2), and 16 sagittal sections of the first ones were used. The proximal and distal planes were compared, defining the following measurements: coronary band-extensor process, distal phalanx apex-hoof wall, sole dermis, middle stratum, parietal dermis, lamellar layer, the sublamellar dermis, and ratios between them. Most of the measurements were consistent among methods. Some showed measurement differences and a minority was impossible to determine. The transmural technique allowed for the observation and replication of measurements of the hoof structures, described with other diagnostic aids. It also allowed for the implementation of new measurements that would help to determine the spatial location of the distal phalanx. Additionally, it contributes to the visualization of normal findings, which will be useful to compare variations in the different phases of laminitis.

Effect of ambulation following 18F-fluorodeoxyglucose injection on standing positron emission tomography of the healthy equine digit.

OBJECTIVE: Measure 18F-FDG uptake in digital tissues of healthy horses subjected to different ambulatory conditions between the time of injection and positron emission tomography (PET) scan acquisition. ANIMALS: 8 healthy adult horses. METHODS: Horses were walked (AMB) or tied in stalls (NONAMB) immediately after injection with ∼1.5 MBq/kg 18F-FDG until scan acquisition using a randomized crossover design. Steps were quantified using accelerometers. Standardized uptake values (SUV; mean and maximum) in digital tissues including the dorsal lamellae (proximal, middle, and distal), quarter lamellae (medial and lateral), and coronary band were analyzed using a mixed-effects linear regression model. RESULTS: Mean (95% CI) step count for AMB (569[484-653]) was higher than NONAMB (88[24-152]) P = <.001. The SUVmax (but not SUVmean) was increased in AMB compared with NONAMB in the proximal (2.74[2.52-2.98] vs 2.42[2.05-2.78]; P = .04) and middle (2.74[2.37-3.11] vs 2.36[2.05-2.68]; P = .03) dorsal lamellae but was not different in the distal lamellae or coronary band. In the medial quarter lamellae, both SUVmax (2.53[1.58-3.48] vs 2.07[0.81-3.33]; P = .01) and SUVmean (1.90[1.55-2.25] vs 1.49[0.91-2.06]; P = .007) were increased in AMB compared with NONAMB. The medial quarter lamellae also had lower SUVmax (P = .002) and SUVmean (P = .04) compared with the lateral quarter and lower SUVmax compared with the mid-dorsal lamellae (P = .01). CLINICAL RELEVANCE: Lamellar 18F-FDG uptake was affected by ambulatory activity mostly in the medial quarter; however, this effect was relatively small and unlikely to interfere with clinical detection of laminitis.

Transmural Ultrasonography in the Evaluation of Horse Hoof Internal Structures: Comparative Qualitative Findings-Part 1.

Ultrasonography is commonly used to evaluate equine lameness-related structures, but traditional hoof approaches cannot adequately visualize internal structures such as the lamellar layer. To address this limitation, we used 62 healthy hooves without digital radiographic abnormalities, made up of thirty anatomical pieces (phase 1) and thirty-two hooves from living horses (phase 2). In both phases, half of the digits were submerged in water (group 1) and the other half in water and ice (group 2) for 24 h. Ultrasonographic views and temperature and humidity measurements were taken every two hours, and sagittal sections were obtained in phase 1. Good quality images were obtained in both phases. The transmural technique allowed the evaluation of several structures of the DEJ (tubular and lamellar strata of the hoof wall, sublamellar dermis, and solar and coronary papillae) and of the distal phalanx (extensor process, parietal surface, and apex). Our findings suggest that the transmural technique following hoof submersion can be useful for internal evaluation of hoof conditions, such as laminitis. However, further validation of the technique in natural or experimental cases is required.

Systematic review of the relationship between rumen acidosis and laminitis in cattle.

Laminitis is usually considered a consequence of digestive disorders that reduce ruminal pH. However, it is still not clear the direct relation between low ruminal pH provoked by excessive fast-digesting carbohydrate ingestion and laminitis, considering indicators, signs, and diagnosis aspects. This study aimed to clarify the association between different clinical presentations of laminitis with ruminal acidosis provoked by diet using the systematic review methodology. Three electronic databases were used: ISI Web of Science, PubMed, and Scopus. A total of 339 manuscripts were identified and only 16 were included. Manuscripts were published between 2000 and 2021 in 11 different peer-reviewed journals. Fifteen studies confirmed the occurrence of ruminal acidosis. The main indicators used were ruminal pH and clinical signs, such as anorexia, depression, discomfort and diarrhea. Two of the studies that administered oligofructose to induce acidosis and acute laminitis did not observe clinical signs of laminitis, using lameness score or hooves' sensitivity as an indicator. Various diagnostic methods were used to describe laminitis, like thermography, hoof biopsy, sensitivity test, and visual inspection. Although the variety of laminitis indicators used in the included studies, we evidence the existence of an association between diet (high level of fast-digesting carbohydrates), ruminal acidosis, and acute laminitis, mostly in the short-term acidosis' induction protocols, but the mechanism of action is still not clear.

Hoof Unevenness in Juvenile Quarter Horses During First 6 Months of Training.

The role of hoof morphology is increasingly recognized as a factor associated with lameness incidence in performance horses. The primary objective was to evaluate effect of training initiation on hoof unevenness in Quarter Horses (n = 42; 29 2-year-olds, 13 3-year-olds) over 6-months (m) in training (m0, m2, m4, and m6). Horses were objectively assessed for lameness (inertial sensor system) and photographs and radiographs of feet were taken. Hoof measurements were taken (palmar/plantar angles, frog base width/length, toe length/angle, heel length/angle, heel/foot width, wall height/angle), and analyzed with regards to laterality. Front and hindfoot pairs were determined even if toe angles were within 1.5°. Statistical analyses were performed (Fisher's exact test, mixed-model linear regression, P < .05). There were no differences in distal phalanx palmar/plantar angle between lame/nonlame forelimbs (P = .54) or hindlimbs (P = .20). Unevenness between front feet was seen in toe angle m6 (P < .001), heel length m6 (P = .01) and heel angle over time (P = .006). Unevenness between hind feet was seen at m6 in toe angle (P < .001), heel length (P = .009) and heel angle (P = .02). Lameness incidence did not differ between even and uneven footed horses in forelimbs (P = .64) or hindlimbs (P = .09). In uneven feet, there was no difference in lameness between high versus low foot in forelimbs (P = .34) or hindlimbs (P = .29). Limitations include lack of control group not entering training, lack of consistency in timing data collection to previous trimming, and small sample size. In summary, differences in foot measurements and laterality were noted over time following training initiation in juvenile Western performance horses.

Occurrence of clinical laminitis after adaptation to confinement: effects on morphology, density, and mineral composition of the hoof of Nellore cattle after finishing / Ocorrência de laminite clínica após adaptação ao confinamento: efeitos na morfologia, densidade e composição mineral do casco de bovinos Nelore após terminação

Laminitis is a disease that affects the dermis and epidermis of the bovine hoof, generating changes in the hoof capsule. This study evaluated the effects of clinical laminitis diagnosed after the adaptation phase to confinement on the morphology, density, and mineral composition of the hoof of Nellore cattle after finishing. The animals were separated in the first weeks of confinement into a sick group (SG), with clinical laminitis, and a healthy group (HG). SG animals had higher heel length, dorsal wall length, toe height, and diagonal hoof length (p<0.05) than healthy animals. The dermal laminae had similar measurements for thickness, length, and spacing between them between SG and HG. Animals with laminitis showed congestion, hemorrhage, and basement membrane irregularities on histology. Computed microtomography (µCT) revealed that the hoof density of sick animals is lower than healthy ones. According to the mineral composition by energy-dispersive X-ray fluorescence (ED-XRF) spectrometry, the hooves of animals with laminitis (SG) and healthy ones (HG) were not biochemically different. Therefore, the occurrence of clinical laminitis in Nellore cattle in the first weeks of confinement causes an increase in the morphometric parameters of the hoof capsule and a reduction in the density of the abaxial hoof wall evaluated after the finishing period. This disease does not promote changes in the histomorphometric parameters of the dermal laminae and the percentage of minerals in the abaxial hoof wall.

A laminite é uma doença que afeta a derme e epiderme do casco de bovinos gerando alterações no estojo córneo. O estudo avaliou os efeitos da laminite clínica diagnosticada após a fase de adaptação ao confinamento na morfologia, densidade e composição mineral do casco de bovinos da raça Nelore após terminação. Nas primeiras semanas de confinamento, os animais foram separados em um grupo doente (GD) com laminite clínica e em um grupo saudável (GS). Os animais do GD apresentaram maior comprimento de talão, comprimento da parede dorsal, altura da pinça e comprimento diagonal do casco (p<0,05) do que os saudáveis. As lâminas dérmicas tiveram medidas semelhantes para espessura, comprimento e espaçamento entre elas entre GD e GS. Animais doentes apresentaram congestão, hemorragia e irregularidades da membrana basal na histologia. A microtomografia computadorizada (µCT) revelou que a densidade do casco de animais doentes é menor do que o saudável. Para a composição mineral por meio da espectrometria de fluorescência de raio-X por dispersão de energia (ED-XRF), o casco dos animais doentes (GD) e dos saudáveis (GS), não se mostraram diferentes bioquimicamente. Conclui-se que a ocorrência de laminite clínica em bovinos da raça Nelore nas primeiras semanas de confinamento ocasiona aumento de parâmetros morfométricos do estojo córneo e redução da densidade da parede abaxial do casco, avaliados após o período de terminação. Essa enfermidade não promove modificações nos parâmetros histomorfométricos das lâminas dérmicas e na porcentagem de minerais da parede abaxial do casco.

The influence of productivity indicators on the culling of dairy cows in the sharply continental climate of Kazakhstan / O impacto dos indicadores de produtividade no abate de vacas leiteiras no clima acentuadamente continental do Cazaquistão

This article presents the results of the culling of cows of the Simmental and Holstein breeds in the Republic of Kazakhstan. The purpose of the research was to study the actual number of culled cows of dairy productivity in the farms of the Republic of Kazakhstan to determine its norm. The object of research were cows of Simmental (18,462 heads) and Holstein (17,862 heads) breeds in various regions of the republic. The research was carried out according to generally accepted zootechnical methods using statistical data processing using RStudio. The results of the studies showed that the percentage of culling increases in cows of the Simmental and Holstein breeds and amounts to 19.7 and 22.9%, respectively. The analysis of the retirement of full-aged cows of the Simmental breed showed that the main causes are hoof diseases (up to 26%), low reproductive function (up to 21%), low productivity (up to 18%). Holstein cows had an increase in disposals in all categories except for disposals for various reasons, for problems with reproduction, the disposal is up to 21%. The determination of the relationship between productivity and retirement in the Simmental breed cows showed that with age and increased lactation, the proportion of retired cows also increases, in the Holstein breed, with increased productivity, the percentage of culled animals also increases.

Este artigo apresenta os resultados do abate de vacas Simental e Holstein na República do Cazaquistão. O objetivo do estudo foi estudar o número real de vacas abatidas na direção da produtividade leiteira nas fazendas da República do Cazaquistão para determinar sua norma. O estudo incluiu vacas Simental (18.462 cabeças) e Holstein (17.862 cabeças) em diferentes regiões da República. A pesquisa foi conduzida de acordo com métodos zootécnicos geralmente aceitos, adotando o processamento estatístico de dados, usando o RStudio. Os resultados da pesquisa mostraram que as vacas Simental e Holstein aumentaram a taxa de abate para 19,7% e 22,9%, respectivamente. A análise da alienação de vacas Simental de meia-idade mostrou que as principais causas são doenças dos cascos (até 26%), baixa função reprodutiva (até 21%) e baixa produtividade (até 18%). As vacas Holstein tiveram um aumento na alienação em todas as categorias, exceto a alienação por várias razões; devido a problemas reprodutivos, a alienação é de até 21%. A determinação da relação entre a produtividade e a alienação em vacas Simental mostrou que a proporção de vacas eliminadas aumenta com a idade e o aumento da lactação, enquanto a porcentagem de animais eliminados aumenta com a produtividade na raça Holstein.

Comparison of the Mineral Profile of Two Types of Horse Diet, Silage and Commercial Concentrate, and Their Impacts on Hoof Tensile Strength.

The type of diet that a horse consumes is one of the most important factors determining the mineral profile and tensile strength of its hooves, so the quality and nutritional value of the supplied feed are fundamental to achieving satisfactory hoof quality. The objective of this study was to compare the differences in the mineral concentrations of sodium (Na), potassium (K), magnesium (Mg), zinc (Zn), and Iron (Fe) between two diets, namely silage and a commercial concentrate, using atomic absorption spectrometry and to determine which led to higher increases in the hoof tensile strength of horses consuming these diets. Thirty-two Spanish horses were randomly divided into two groups, where the diet of the horses in group 1 was silage oat hay, and that of the horses in group 2 was a commercial concentrate and oat hay. Both diets were provided for 12 months. The hoof tensile strength was then measured using an Instron universal testing machine. Mg and Fe levels were higher (p < 0.05) in the silage than in the commercial concentrate, and hoof Mg, Zn, K, and tensile strength were also influenced by the hormonal stage (p < 0.05). The type of diet directly affected the hoof Mg, Zn, K, Na, and tensile strength (p < 0.05), which Mg, K and Na were higher in horses fed with concentrate. It was found that for each unit of Zn (µg/g and Na (µg/g)), in the hoof, the tensile strength is affected by −0.10 N/mm2 and −0.003 N/mm2, respectively for each mineral.

Mannheimia varigena as the etiologic agent of lameness and coronary band lesion in cattle / Mannheimia varigena como agente etiológico de claudicação e lesão na banda coronária em bovinos

Mannheimia varigena was identified as the etiologic agent of lameness and coronary band lesion in 30% of cattle in a farm located in Rio Grande do Sul, Brazil. Swab samples from the lesions were cultured in McConkey Agar and Blood Agar for microbiological identification. Culture growth was submitted to Gram staining and Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) identification. Antimicrobial susceptibility test based on disc diffusion was performed for three antibiotics: ceftiofur, gentamicin and florfenicol. Furthermore, molecular characterization of 16S rDNA gene sequencing was performed and the data was used in a phylogenetic analysis. For that purpose, total DNA was extracted by thermo extraction directly from the bacterial colonies and the polymerase chain reaction (PCR) was performed. Gram-negative Mannheimia varigena strain LBV010/22 was identified as the causative of the lesions. The strain was susceptible to all antibiotics tested. The phylogenetic analysis demonstrated that the analyzed strain is closely related to M. varigena strains from pyelonephritis and respiratory tract. Overall, this is the first report of M. varigena as the causative agent of coronary band injury in bovine. Therefore, our findings show the importance of an accurate microbiological identification of infectious agent in lameness cases in order to prevent the occurrence and perform an appropriate treatment in the future.

Mannheimia varigena foi identificada como agente etiológico de claudicação e lesão de banda coronária em 30% dos bovinos de uma fazenda localizada no Rio Grande do Sul, Brasil. Amostras de swab das lesões foram cultivadas em Ágar McConkey e Ágar Sangue para identificação microbiológica. O crescimento da cultura foi submetido à coloração de Gram e identificação por Espectrometria de Massa de Ionização por Dessorção a Laser Assistida por Matriz (MALDI-TOF MS). O teste de suscetibilidade antimicrobiana baseado na difusão em disco foi realizado para três antibióticos: ceftiofur, gentamicina e florfenicol. Além disso, foi realizada a caracterização molecular do sequenciamento do gene 16S rDNA e o resultado utilizado para análise filogenética. Para tanto, o DNA total foi extraído por termoextração diretamente das colônias bacterianas e uma reação em cadeia da polimerase (PCR) foi realizada. Foi identificada como causadora das lesões a cepa gram-negativa de Mannheimia varigenaLBV010/22. Ela foi suscetível a todos os antibióticos testados. A análise filogenética demonstrou que a cepa analisada está intimamente relacionada às M. varigena presentes em pielonefrite e no trato respiratório. No geral, este é o primeiro relato de M. varigenacomo agente causador de lesão de banda coronária em bovinos. Portanto, nossos achados mostram a importância de uma identificação microbiológica precisa do agente infeccioso nos casos de claudicação, a fim de prevenir a ocorrência e realizar um tratamento adequado no futuro.

Influences of the Seasons of the Year and Physiographic Regions on the Levels of Calcium, Copper and Zinc in the Hoof Capsule of Foals Pre- and Postweaning Raised in Native Pasture.

This study evaluated the levels of calcium (Ca), copper (Cu) and zinc (Zn) in the hoof of Criollo foals, pre- and postweaning, correlating them with the concentrations of these inorganic chemical compounds in soil and pasture in the different seasons of the year. We used 41 preweaning foals and 28 postweaning foals. Seventeen forage samples were collected in four seasons, later 10 soil samples per property in five distinct physiographic regions (Santa Maria, Dilermando de Aguiar, Jaguarão, Arroio Grande and Pelotas). There was variability in Ca, Cu and Zn concentrations in the hoof foal between distinct physiographic regions (P < .05), and between seasons. There was no association of preweaning and postweaning Ca levels with forage in the different physiographic regions. The concentrations of Cu and Zn showed positive association (R = 0.69, 0.43; P < .05) with the native pastures in the different physiographic regions in preweaning. In postweaning, only Cu was positively associated (R = 0.74; P < .05). Different season and physiographic regions influence the levels of Ca, Cu and Zn in the hoof capsule and native pasture during the pre- and postweaning stages.

Amputation of the front medial digit of a Holstein cow - successful parturition and milk production

Background: Diseases of the bovine digit and hoof remain major problems in dairy farming and the beef cow industry. Severe claudication accompanying swelling and pain at the lesion is often observed in deep digital sepsis, septic arthritis, severe sole ulcers, and chronic interdigital phlegmon. In addition, digital amputation is often performed in cases of white line disease or severe trauma, such as bone fractures. There are few reports of amputation of the medial digit of the bovine front hoof. In this case, amputation of the medial digit of the front leg of a pregnant cow was performed; its hospitalization and return to productivity is reported. Case: The bovine was a 9-year-old Holstein cow in the 6th month of pregnancy, weighing 671 kg. Upon admission, the cow could not bear weight on its right front leg, and swelling and a purulent discharge were observed in the coronary area of the medial digit. X-ray examination results indicated a periosteal reaction centered on the 3rd phalanx of the medial digit of its right front leg hoof and slight periosteal reactions at the adaxial sides of the middle and proximal phalanges, strongly suggestive of septic arthritis caused by infection. According to the X-ray examination results, no abnormalities of the lateral digit of the front right hoof were observed; thus, it was estimated that the post-amputation hoof would be able to bear weight. Therefore, a decision was made to perform immediate amputation of the medial digit of the right front leg hoof to reduce pain for improved delivery of the offspring and improved milk production during the lactation period, rather than allowing the lesion progress until the dry period or the expected date of delivery. According to the X-ray examination results, amputation of the 1st phalanx alone was expected to suffice for removal of the cause of the pain; thus, a decision was made to perform amputation at the edge adjacent to the 2nd phalanx. The right front medial digit was prepared for aseptic surgery, and infiltration anesthesia was performed. An incision was made with a surgical knife at the interdigit of the right front limb. A wire saw was inserted into the site to cut the 2nd phalanx in the anti-axial direction down to the skin to resect the lesion. White viscous pus was discharged at the resection site; therefore, the wound was lavaged with tap water and packed with povidone iodine-impregnated gauze. The wound was also covered with a diaper and dressed with non-elastic and elastic bandages. The dressing was changed daily to aid wound healing. No problems were observed in the standing-up motion or other relevant movements immediately after the surgery. Granulation tissue formed rapidly, approximately 2 weeks after the surgery, and the lesion dried gradually. Approximately one month after the surgery, the subject exhibited little difficulty in both standing up and walking. The subject successfully delivered its 7th offspring at the farm on postoperative day 93. Discussion: The animal of this study was a 9-year-old, pregnant cow, and although amputation of the front medial digit is a relatively rare procedure, the cow was able to deliver and return to production, owing to sufficient postoperative treatment and care. The case also demonstrated the advantage of X-ray examination in bovine hoof diseases for accurate diagnosis, precise operation, and prognostic assessment.

Occurrence of foot diseases in cattle attended at the Clínica de Bovinos de Garanhuns: Epidemiological, clinical, therapeutic and economic aspects / Ocorrência de afecções podais em bovinos atendidos pela Clínica de Bovinos de Garanhuns: aspectos epidemiológicos, clínicos, terapêuticos e econômicos

The objective was to study the occurrence of foot disorders in cattle treated at the Clínica de Bovinos de Garanhuns, campus of the Universidade Federal Rural de Pernambuco from 1999 to 2021. A retrospective study of the medical records was carried out, with a total of 334 cases, in which 613 lesions were diagnosed. A frequency distribution, with simple mean and standard deviation was performed to evaluate the data. Interdigital dermatitis was more frequent in 12.4% (76/613), double sole in 9.79% (60/613), chronic laminitis in 8.81% (54/613), sole ulcer in 7.83% (48 /613), and interdigital hyperplasia in 7.24% (45/613). Laminitis and its consequences accounted for 45% of the total injuries identified, followed by 36% of injuries of secondary or uncertain cause, and 19% from infectious diseases. The distribution of lesions between the limbs was 68% in the pelvic and 32% in the thoracic limbs. Females, raised in a semi-intensive system, Holstein, with a body score of III, and large size were more affected. Lameness was present in 78% (260/334), while 10% (33/334) did not present lameness. The case fatality and recovery rates were 9% (31/334) and 73% (243/334), respectively. In total, 51% of cases occurred in the rainy season and 49% in the dry season. The main cities of origin were Bom Conselho 22.75% (76/334), Garanhuns 18.86% (63/334), and Brejão 12.57% (42/334). The estimated cost of treatment was US$ 150.13/case. Diseases are probably directly linked to management failure on the property due to the nature of the diagnosed diseases, in addition to the significant cost of the treatment of these animals, with the need for prophylactic measures in order to avoid the economic losses associated with foot diseases.

Objetivou-se estudar a ocorrência das afecções podais em bovinos atendidos na Clínica de Bovinos de Garanhuns, Campus da Universidade Federal Rural de Pernambuco, no intervalo de 1999 a 2021. Realizou-se estudo retrospectivo dos prontuários, com total 334 casos, dos quais foram diagnosticadas 613 lesões digitais. Foi realizada a distribuição de frequência, média simples e desvio padrão para avaliação dos dados. A dermatite interdigital foi a mais frequente, sendo observada em 12,4% (76/613) dos casos, seguida por sola dupla 9,79% (60/613), laminite crônica 8,81% (54/613), úlcera de sola 7,83% (48/613) e a hiperplasia interdigital 7,24% (45/613). A laminite e suas consequências representaram 45% do total de lesões identificadas, acompanhadas por 36% das injúrias de causa secundárias ou incertas e de doenças infecciosas com 19%. A distribuição das lesões entre os membros foi de 68% nos pélvicos e 32% nos torácicos. As fêmeas criadas em sistema semi-intensivo, holandesas, com escore corporal III e porte grande eram mais acometidas. A claudicação estava presente em 78% dos animais, enquanto 10% não claudicavam. As taxas de letalidade e recuperação foram de 9% (31/334) e 73 % (243/334), respectivamente. No período chuvoso foram 51% dos casos e 49% na época seca. Os principais municípios de origem foram Bom Conselho 22,75% (76/334), Garanhuns 18, 86% (63/334) e Brejão 12,57% (42/334). O custo estimado com tratamento foi de US$ 150,13/caso. Provavelmente falhas de manejo nas propriedades foram importantes fatores de risco para as doenças. Sugere-se a implementação de medidas profiláticas para evitar as perdas econômicas associadas às enfermidades podais.

Metabolic imbalances, hoof injuries, and metabolic profile of high-producing Holstein × Gir cowsshowing lameness / Desequilíbrios metabólicos, lesões nos cascos e perfil metabólico de vacas Holandesa × Gir de alta produção apresentando claudicação

This study attempted to determine the associations between metabolic imbalances and lameness or hoof injuries in high-producing Holstein × Gir cows, and to determine whether the metabolic profile affects the occurrence of lameness. Eighty cows were followed from -60 to 60 days relative to calving and hoof injuries were reported on days -60, 7 and 60. Locomotion score (LS), body condition score (BCS), the concentrations of non-esterified fatty acids, ß-hydroxybutyrate, glucose, cholesterol, albumin, total protein, blood urea nitrogen (BUN), calcium, phosphorus, and magnesium, and the activity of aspartate aminotransferase were determined at days -42, -21, -7, 0, 7, 21 and 42. The McNemar and Chi-square tests were used to compare frequencies of lameness and hoof injuries over time and to verify the associations between lameness, BCS, hoof injuries, and metabolic disorders. Two-way repeated measures ANOVA was used considering groups (non-lame × lame cows) and variations of BCS and metabolites over time. Lameness and hoof injuries increased between days -60 (20% and 66.3%) and 60 (44.7% and 98.6%). Excessive postpartum loss of BCS (P=0.017) and subclinical hypocalcemia (P=0.012) were associated with lameness on day 60. In general, the metabolic profile did not differ between lame and non-lame cows but cholesterol, albumin, BUN and magnesium concentrations were higher in non-lame cows. The postpartum decrease in BCS can affect the occurrence of lameness, and the metabolic profile of lame cows shows little difference from that of non-lame cows.

Este estudo objetivou verificar as associações entre desequilíbrios metabólicos e claudicação ou lesões nos cascos em vacas mestiças Holandesa × Gir de alta produção e determinar se o perfil metabólico afeta a ocorrência de claudicação. Oitenta vacas foram acompanhadas de -60 a 60 dias em relação ao parto e as lesões nos cascos foram avaliadas nos dias -60, 7 e 60. O escore de locomoção (EL), o escore de condição corporal (ECC), as concentrações de ácidos graxos não esterificados, ß-hidroxibutirato, glicose, colesterol, albumina, proteína total, nitrogênio ureico no sangue (BUN), cálcio, fósforo e magnésio e a atividade da aspartato aminotransferase foram determinados nos dias -42, -21, -7, 0, 7, 21 e 42. Os testes de McNemar e de Qui-quadrado foram empregados para comparar as frequências de claudicação e de lesões nos cascos ao longo do tempo e para verificar as associações entre claudicação, ECC, lesões nos cascos e distúrbios metabólicos. A análise de variâncias de medidas repetidas bifatorial foi usada considerando-se grupos (vacas com claudicação × vacas sem claudicação) e variações de BCS e de metabólitos ao longo do tempo. A claudicação e as lesões nos cascos aumentaram entre os dias -60 (20% e 66,3%) e 60 (44,7% e 98,6%). A perda excessiva de ECC no pós-parto (P=0,017) e a hipocalcemia subclínica ao parto (P=0,012) foram associadas com claudicação no dia 60. Em geral, o perfil metabólico não diferiu entre vacas com e sem claudicação, mas as concentrações de colesterol, albumina, BUN e magnésio foram maiores em vacas sem claudicação. A redução do ECC no periodo pós-parto pode afetar a ocorrência de claudicação, e o perfil metabólico das vacas claudicantes apresenta pouca diferença em relação ao das vacas não claudicantes.

Determination of Positional Parameters of the Distal Phalanx Within the Hoof Capsule in Sound Colombian Paso Horses.

The economic relevance, populational importance and expansion of the Colombian Paso Horse to other latitudes calls for a growth in studies based on this type of horse. Lack of written reports about the relationship of the distal phalanx (DP) within the hoof in this gaited horse makes it important to establish a baseline to determine hoof health and possible alterations. The purpose of this study was to report, for the first time, the positional parameters of the distal phalanx, and its relationship within the hoof in sound Colombian Paso Horses. A latero-medial radiographic image of each digit was taken in 45 horses between 3 and 5 years old, distributed into groups according to the gaits determined by FEDEQUINAS. Three angles and three distances were measured. The dorsal wall thickness (W-T) was measured proximally and distally, and the sole depth (P-S) was measured dorsally and palmarly/plantarly. As expected, these distances showed moderate to strong positive correlations in front (W-Tp/W-Td r = 0.53; P-Sd/P-Sp r = 0.72) and hind feet (W-Tp/W-Td r = 0.61; P-Sd/P-Sp r = 0.71). The palmar/plantar angle of the distal phalanx (PA) and sole depth (P-S) showed that the distal phalanx of the hind feet is flatter compared to the front. The results of this study show differences in the positional parameters of distal phalanx compared to other breeds of horses and provides information for veterinarians and farriers working with Colombian Paso Horses.

Apoptosis in epithelial cells and its correlation with leukocyte accumulation in lamellar tissue from horses subjected to experimental sepsis-associated laminitis.

Inflammation and apoptosis in the hoof lamellar interface both contribute to the early stages of sepsis-associated laminitis, but it is not clear whether apoptosis is occurring before the onset of inflammation or is being provoked by inflammation. Apoptosis and inflammation were therefore measured in lamellar tissues obtained at different time points throughout the early stages of experimentally induced laminitis. Apoptotic cells and leukocyte were enumerated in archived paraffin embedded lamellar tissue samples from previous experiments in which acute laminitis was induced using Black Walnut Extract (BWE) or starch (CHO). BWE-derived samples from 20 horses were allocated into four groups: Control (CON = 5); Early Time Point (ETP, 1.5 h after induction, n = 5); Developmental Time Point (DTP, 3-4 h after induction, n = 5); Obel Grade 1 (OG1, Onset of Lameness, n = 5). CHO-derived samples from 25 horses were allocated into four groups: CON (n = 8); DTP (10-12 h after induction, n = 6); OG 1 (n = 6); Obel 3 (OG3, lameness progression, n = 5). Apoptotic cells were enumerated using a horse validated TUNEL technique. Compared to controls, significant increases in apoptotic cell counts were not detected in lamellar epithelial cells during the developmental phase or at the onset of lameness during laminitis induction. A negative correlation between apoptosis and leukocyte infiltration was detected in the BWE model (P < 0.05). In conclusion, apoptosis does not play an important role in the initial stages of sepsis-related laminitis.

Preliminary Study on the Connection Between the Mineral Profile of Horse Hooves and Tensile Strength Based on Body Weight, Sex, Age, Sampling Location, and Riding Disciplines.

Hoof mineral profile is important as it could affect locomotion. Factors such as body weight, sex, age, and riding disciplines affect hoof mineral profile. In Mexico and globally, studies are needed on the characterization of mineral profile of hooves and tensile strength, as this could help to prevent overgrowth or microfractures. Therefore, in the present survey, 165 samples of equine hoof cuttings from different sex, ages, breeds, and riding disciplines from different regions of Mexico were analyzed for their mineral composition, and a universal testing machine was used to measure tensile strength. More than half of the samples were from males (63%) and aged 3 to 5 years (52%). Most samples were obtained from horses used for reproduction (36%) and working (29%) purposes. The most preponderant minerals were K (3,416 µg/g), Na (2,242 µg/g), and Ca (631 µg/g). Tensile strength ranged from 1.2 to 45 N. Females had higher (P < 0.05) amounts of Zn than males. Animals younger than 3 years old have lower (P < 0.05) levels of Na than those between 3 and 5 years old. Horses used for reproduction had lower (P < 0.05) Mg concentrations than animals used for running and working. Tensile strength was similar between demographic characteristics. Horses from Santa Gertrudis military ranch had higher (P < 0.05) levels of Ca, Se, and Na compared with horses from other sampling location. Copper was higher (P < 0.05) in horses from racecourse. Potassium was higher (P < 0.05) in horses from the Presidential General Staff. Overall, there was no evident connection between sex, ages, breeds, and riding disciplines from different regions of Mexico and the mineral composition of the hoof or its tensile strength. Further research should focus on the relation on specific feeding regimes, horse individual characteristic, hoof mineral contents, and tensile strength.

Mineral composition and microstructure of the abaxial hoof wall in dairy heifers after biotin supplementation.

The aim of this study was to evaluate the effect of daily biotin supplementation on the mineral composition and microstructure of the abaxial hoof wall in dairy heifers. The heifers were housed on a concrete floor and fed for weight gain more than 800 g per day, which is a challenging environment for the hoof. Twelve crossbred dairy heifers (Jersey × Holstein) were divided into two treatment groups. Animals in the control group (n = 6) received a diet without supplemental biotin, while the heifers in the biotin-supplemented feed group (n = 6) each received 20 mg of biotin daily for 120 days. Samples of the abaxial hoof wall were collected from the outer claw of the fore and hind limb, before and after supplementation. The samples were evaluated by X-ray fluorescence spectrometry, computed microtomography, atomic force microscopy and confocal laser scanning microscopy. Biotin supplementation increased the sulphur content and decreased the calcium and potassium content in the abaxial hoof wall. Biotin treatment also increased the percentage of horn tubules with smaller diameter marrow (17-51 µm). However, biotin did not influence the surface relief of the hoof wall, suggesting that its action is limited to the inner layers of the stratum corneum. Daily supplementation with 20 mg of biotin promoted changes in the mineral composition and microstructure of abaxial hoof wall of crossbred dairy heifers. These findings suggest biotin supplementation improves hoof quality and may help to understand the function of biotin in the stratum corneum.