RESUMO
Contagious ovine digital dermatitis (CODD) causes a severe, infectious foot disease and lameness of sheep, is common within the UK and is now also emerging in other countries. As well as causing severe animal welfare issues, huge economic losses emerge from the disease due to weight loss/lack of weight gain, and veterinary treatments. CODD lesion progress is measured, with a scoring system from 1 (early lesions) to 5 (healed). Here, using samples from an experimental flock infected by natural means, samples were taken from CODD stage 5 lesions, post treatment, and subjected to bacterial isolation and MLST using previously published methods. Sequences were compared to others from the same flock, and those from previous studies. All CODD 5 lesions produced viable Treponema spp. bacteria. High levels of variation of bacteria were seen, with 12 sequence types (STs) for T. medium phylogroup (11 new), 15 STs for T. phagedenis phylogroup (9 new) and six T. pedis STs, of which two were new. This study shows that CODD stage 5 lesions still contain viable bacteria, representing all three known pathogenic Treponema spp. phylogroups, and these may thus play a role in disease transmission and epidemiology despite appearing healed after treatment. The high level CODD treponeme variability within an infected flock where sheep were bought from different sources, as might occur in common agricultural practice, may suggest reasons as to why the bacterial disease is difficult to treat, control and eradicate, and adds further complexity to the polybacterial pathogenesis of these lesions.
Assuntos
Dermatite Digital , Tipagem de Sequências Multilocus , Doenças dos Ovinos , Treponema , Infecções por Treponema , Animais , Ovinos , Treponema/genética , Treponema/classificação , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/transmissão , Dermatite Digital/microbiologia , Dermatite Digital/transmissão , Tipagem de Sequências Multilocus/veterinária , Infecções por Treponema/veterinária , Infecções por Treponema/microbiologia , Infecções por Treponema/transmissãoRESUMO
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.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Fermentação , Animais , Bovinos , Estudos Retrospectivos , Dermatite Digital/microbiologia , Dermatite Digital/prevenção & controle , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Japão , Estudos Transversais , Bactérias Anaeróbias , Casco e Garras/microbiologiaRESUMO
Digital dermatitis (DD) is an ulcerative foot lesion on the heel bulbs of dairy cattle. DD is a polymicrobial disease with no precise etiology, although Treponema spirochetes are found disproportionally abundant in diseased tissue. Within Treponema, several different species are found in DD; however, the species Treponema phagedenis is uniformly found in copious quantities and deep within the skin layers of the active, ulcerative stages of disease. The pathogenic mechanisms these bacteria use to persist in the skin and the precise role they play in the pathology of DD are widely unknown. To explore the pathogenesis and virulence of Treponema phagedenis, newly isolated strains of this species were investigated in a subcutaneous murine abscess model. In the first trial, a dosage study was conducted to compare the pathogenicity of different strains across three different treponemes per inoculum (TPI) doses based on abscess volumes. In the second trial, the expression levels of 11 putative virulence genes were obtained to gain insight into their involvement in pathogenesis. During the RT-qPCR analysis, it was determined that genes encoding for two metal-ion import lipoproteins and two adherence genes were found highly upregulated during infection. Conversely, two genes involved in motility and chemotaxis were found to not be significantly upregulated or utilized during infection. These results were supported by gene expression data from natural M2 lesions of dairy cattle. This gene expression analysis could highlight the preference in strategy for T. phagedenis to persist and adhere in the host rather than engage in motility and disseminate.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Treponema , Infecções por Treponema , Animais , Bovinos , Treponema/genética , Treponema/patogenicidade , Treponema/isolamento & purificação , Dermatite Digital/microbiologia , Infecções por Treponema/microbiologia , Camundongos , Doenças dos Bovinos/microbiologia , Aderência Bacteriana , Regulação Bacteriana da Expressão Gênica , Virulência/genética , Feminino , Metais/metabolismo , Abscesso/microbiologia , Fatores de Virulência/genéticaRESUMO
Digital dermatitis (DD) is a bovine claw disease responsible for ulcerative lesions on the planar aspect of the hoof. DD is associated with massive herd outbreaks of lameness and influences cattle welfare and production. Early detection of DD can lead to prompt treatment and decrease lameness. Computer vision (CV) provides a unique opportunity to improve early detection. The study aims to train and compare applications for the real-time detection of DD in dairy cows. Eight CV models were trained for detection and scoring, compared using performance metrics and inference time, and the best model was automated for real-time detection using images and video. Images were collected from commercial dairy farms while facing the interdigital space on the plantar surface of the foot. Images were scored for M-stages of DD by a trained investigator using the M-stage DD classification system with distinct labels for hyperkeratosis (H) and proliferations (P). Two sets of images were compiled: the first dataset (Dataset 1) containing 1,177 M0/M4H and 1,050 M2/M2P images and the second dataset (Dataset 2) containing 240 M0, 17 M2, 51 M2P, 114 M4H, and 108 M4P images. Models were trained to detect and score DD lesions and compared for precision, recall, and mean average precision (mAP) in addition to inference time in frame per second (FPS). Seven of the nine CV models performed well compared to the ground truth of labeled images using Dataset 1. The six models, Faster R-CNN, Cascade R-CNN, YOLOv3, Tiny YOLOv3, YOLOv4, Tiny YOLOv4, and YOLOv5s achieved an mAP between 0.964 and 0.998, whereas the other two models, SSD and SSD Lite, yielded an mAP of 0.371 and 0.387 respectively. Overall, YOLOv4, Tiny YOLOv4, and YOLOv5s outperformed all other models with almost perfect precision, perfect recall, and a higher mAP. Tiny YOLOv4 outperformed all other models with respect to inference time at 333 FPS, followed by YOLOv5s at 133 FPS and YOLOv4 at 65 FPS. YOLOv4 and Tiny YOLOv4 performed better than YOLOv5s compared to the ground truth using Dataset 2. YOLOv4 and Tiny YOLOv4 yielded a similar mAP of 0.896 and 0.895, respectively. However, Tiny YOLOv4 achieved both higher precision and recall compared to YOLOv4. Finally, Tiny YOLOv4 was able to detect DD lesions on a commercial dairy farm with high performance and speed. The proposed CV tool can be used for early detection and prompt treatment of DD in dairy cows. This result is a step towards applying CV algorithms to veterinary medicine and implementing real-time DD detection on dairy farms.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Animais , Bovinos , Dermatite Digital/diagnóstico , Doenças dos Bovinos/diagnóstico , Feminino , Algoritmos , Indústria de Laticínios/métodosRESUMO
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. CONCLUSION: 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.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Desinfecção , Treponema , Infecções por Treponema , Animais , Bovinos , Treponema/isolamento & purificação , Dermatite Digital/microbiologia , Infecções por Treponema/veterinária , Infecções por Treponema/microbiologia , Doenças dos Bovinos/microbiologia , Desinfecção/métodos , Feminino , Noruega , Casco e Garras/microbiologia , DNA Bacteriano/análise , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/instrumentaçãoRESUMO
BACKGROUND: Digital dermatitis (DD) is a contagious hoof infection affecting cattle worldwide. The disease causes lameness and a reduction in animal welfare, which ultimately leads to major decreases in milk production in dairy cattle. The disease is most likely of polymicrobial origin with Treponema phagedenis and other Treponema spp. playing a key role; however, the etiology is not fully understood. Diagnosis of the disease is based on visual assessment of the feet by trained hoof-trimmers and veterinarians, as a more reliable diagnostic method is lacking. The aim of this study was to evaluate the use of an enzyme-linked immunosorbent assay (ELISA) on bulk tank milk samples testing for the presence of T. phagedenis antibodies as a proxy to assess herd prevalence of DD in Swedish dairy cattle herds. RESULTS: Bulk tank milk samples were collected in 2013 from 612 dairy herds spread across Sweden. A nationwide DD apparent prevalence of 11.9% (8.1-14.4% CI95%) was found, with the highest proportion of test-positive herds in the South Swedish regions (31.3%; 19.9-42.4% CI95%). CONCLUSIONS: This study reveals an underestimation of DD prevalence based on test results compared to hoof trimming data, highlighting the critical need for a reliable and accurate diagnostic method. Such a method is essential for disease monitoring and the development of effective control strategies. The novelty of ELISA-based diagnostic methods for DD, coupled with the disease's polymicrobial origin, suggests an avenue for improvement. Developing an expanded ELISA, incorporating antigens from various bacterial species implicated in the disease, could enhance diagnostic accuracy. The significance of this study is underscored by the extensive analysis of a substantial sample size (612). Notably, this investigation stands as the largest assessment to date, evaluating the application of ELISA on bulk tank milk for DD diagnosis at the herd level.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Ensaio de Imunoadsorção Enzimática , Leite , Treponema , Animais , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Leite/microbiologia , Suécia/epidemiologia , Dermatite Digital/diagnóstico , Dermatite Digital/microbiologia , Treponema/isolamento & purificação , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/epidemiologia , Feminino , Infecções por Treponema/veterinária , Infecções por Treponema/diagnóstico , Infecções por Treponema/microbiologia , Prevalência , Anticorpos Antibacterianos/análise , Indústria de LaticíniosRESUMO
BACKGROUND: Claw diseases and mastitis represent the most important health issues in dairy cattle with a frequently mentioned connection to milk production. Although many studies have aimed at investigating this connection in more detail by estimating genetic correlations, they do not provide information about causality. An alternative is to carry out Mendelian randomization (MR) studies using genetic variants to investigate the effect of an exposure on an outcome trait mediated by genetic variants. No study has yet investigated the causal association of milk yield (MY) with health traits in dairy cattle. Hence, we performed a MR analysis of MY and seven health traits using imputed whole-genome sequence data from 34,497 German Holstein cows. We applied a method that uses summary statistics and removes horizontal pleiotropic variants (having an effect on both traits), which improves the power and unbiasedness of MR studies. In addition, genetic correlations between MY and each health trait were estimated to compare them with the estimates of causal effects that we expected. RESULTS: All genetic correlations between MY and each health trait were negative, ranging from - 0.303 (mastitis) to - 0.019 (digital dermatitis), which indicates a reduced health status as MY increases. The only non-significant correlation was between MY and digital dermatitis. In addition, each causal association was negative, ranging from - 0.131 (mastitis) to - 0.034 (laminitis), but the number of significant associations was reduced to five nominal and two experiment-wide significant results. The latter were between MY and mastitis and between MY and digital phlegmon. Horizontal pleiotropic variants were identified for mastitis, digital dermatitis and digital phlegmon. They were located within or nearby variants that were previously reported to have a horizontal pleiotropic effect, e.g., on milk production and somatic cell count. CONCLUSIONS: Our results confirm the known negative genetic connection between health traits and MY in dairy cattle. In addition, they provide new information about causality, which for example points to the negative energy balance mediating the connection between these traits. This knowledge helps to better understand whether the negative genetic correlation is based on pleiotropy, linkage between causal variants for both trait complexes, or indeed on a causal association.
Assuntos
Dermatite Digital , Mastite , Animais , Bovinos/genética , Feminino , Celulite (Flegmão) , Lactação/genética , Análise da Randomização Mendeliana , LeiteRESUMO
Treponema spp. are associated with infectious lameness in livestock and wild ruminants. While extensive research has been conducted on cattle, investigations in wild ruminants are scarce. Hoof disease is common in caribou populations (Rangifer tarandus), but investigations are limited due to the remoteness of the Arctic. Our study aimed to assess the presence of Treponema spp. associated with bovine digital dermatitis in caribou. DNA was extracted from coronary band tissues from forty-eight caribou without visible hoof lesions and analyzed using two PCR methods (qPCR and nPCR). Treponema spp. were detected in low copy numbers/mg of tissue (3.6 to 6.6 × 101). T. phagedenis was the most prevalent and abundant species in 58% of samples by qPCR, followed by T. medium (44%), and T. pedis (10%). The qPCR and nPCR agreement ranged between 65% and 75% (Cohen's kappa 0.22-0.51). Sanger sequencing of thirteen nPCR products confirmed that treponemes in caribou are remarkably similar to those found in domestic ruminants and wild elk. Our study highlights the colonization of treponemes in healthy hooves of a wild ruminant in the Arctic, where there is no presence of livestock, and expands knowledge on the host range and distribution of treponemes. These findings also emphasize the need for further research into the multifactorial nature of treponema-associated hoof diseases and the putative role of treponemes in infectious lameness affecting caribou.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Rena , Infecções por Treponema , Bovinos , Animais , Treponema/genética , Coxeadura Animal , Animais Selvagens , Infecções por Treponema/veterináriaRESUMO
Digital dermatitis is one of the most important causes of lameness in dairy cattle, particularly in housed, intensively-managed cattle. The number of modern intensive dairy farms in China has increased markedly in recent years; however, we lack research on digital dermatitis in Chinese dairy cattle. This preliminary study aimed to estimate the prevalence of digital dermatitis on three conveniently selected farms in Jiangsu, China. The washed hind feet of all lactating cows on all three farms were examined during milking with the aid of a mobile phone light source. True prevalence was then estimated from the apparent prevalence using a Bayesian superpopulation approach to account for the imperfect nature of identifying digital dermatitis in cows during milking. Despite none of the farms having thought it necessary to implement routine digital dermatitis monitoring or control, the disease was found on all three sampled farms. All lesions observed were either chronic M4 or M4.1 type-lesions, with no M2 lesions (i.e. acute ulcerated lesions) observed. The estimated true prevalences on the farms were 7.3% (95% credible interval [CrI]: 5.4%-9.6%), 8.3% (95%CrI: 6.3%-10.8%), and 29.8% (95%CrI: 22.9%-37.2%).
Assuntos
Teorema de Bayes , Doenças dos Bovinos , Indústria de Laticínios , Dermatite Digital , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , China/epidemiologia , Prevalência , Dermatite Digital/epidemiologia , FemininoRESUMO
Bovine digital dermatitis (BDD) is an important cause of lameness in dairy cows worldwide. However, very little is known about this disease in Australian herds, which are predominantly managed on pasture. The primary objectives of this cross-sectional study were to describe the presence and prevalence of BDD in Australian dairy herds and to characterize the microbiota of healthy skin and M4 lesions of BDD-affected, pasture-managed cows. Cows from 71 dairy herds were examined at milking time to identify the presence of BDD lesions. True prevalence was estimated using Bayesian methods with informative priors for sensitivity and specificity. Biopsy samples (n = 60) were collected from cows with and without BDD lesions in 7 pasture-based herds. The microbiota in the superficial and deep strata of each tissue biopsy were characterized via sequencing of the V3-V4 region of the bacterial ribosomal RNA gene. Lesions were detected in 1,817 (11.5%) of 15,813 cows and in 68 of 71 (95.8%) herds. The median herd-level apparent and true prevalences of BDD were 8.5% and 18.1%, respectively, but prevalences varied considerably between farms. On farms with BDD, M4 lesions accounted for 70% to 100% of all lesions (interquartile range = 95.1%-100%, median = 100%); M2 lesions (i.e., large ulcerative lesions) were observed at low prevalence (<2.2%) in the few herds (7/71, 9.9%) where they were found. There was a significant difference in the composition of the microbiota between healthy skin and M4 lesions but not between superficial and deep tissue layers. Several gut- and effluent-associated bacterial taxa, including Lentimicrobium and Porphyromonas, which have previously been associated with BDD, were abundant in BDD lesions but not in control biopsies. Our study supports the idea that such taxa are involved in, although possibly not essential to, lesion development and persistence in pasture-managed cows in Australia. Our results also suggest that Dichelobacter may contribute to the disease process. We conclude that BDD is likely to occur in most Australian dairy farms, but that further studies are needed to identify its effect on cow welfare and productivity. Further investigation of the etiology of BDD in Australian dairy herds is also necessary to inform prevention and control strategies.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Bovinos , Animais , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Feminino , Estudos Transversais , Dermatite Digital/epidemiologia , Dermatite Digital/microbiologia , Austrália/epidemiologia , Indústria de Laticínios , Coxeadura Animal/epidemiologia , PrevalênciaRESUMO
Digital dermatitis (DD) is a polybacterial disease endemic to most UK dairy farms. It poses a major financial and welfare threat and is characterized by high incidence and recurrence rates. We aimed to investigate the association between the UK EBV for resistance to digital dermatitis, the digital dermatitis index (DDI), and the frequency of DD, heel horn erosion (HHE), and interdigital hyperplasia (IH) in a population of Holstein dairy cows. We enrolled and genotyped 2,352 cows from 4 farms in a prospective cohort study. Foot lesion records were recorded by veterinary surgeons for each animal at 4 time points during a production cycle, starting at approximately 2 mo before calving and ending in late lactation. Importantly, these records were not used in the calculation of the DDI. Lesion records were matched to the animal's own DDI (n = 2,101) and their sire's DDI (n = 1,812). Digital dermatitis index values in our study population ranged from -1.41 to +1.2 and were transformed to represent distance from the mean expressed in SD. The relationship between the DDI and the presence of DD was investigated using a logistic regression model, with farm, parity, and a farm-parity interaction fitted as covariates. A multivariable logistic regression model was fitted to evaluate the relationship between HHE and DDI with farm fitted as a covariate. Finally, a univariable logistic regression model with DDI as explanatory variable was used to investigate the relationship between IH and DDI. The odds ratio of an animal being affected by DD was 0.69 for 1 SD increase in the animal's DDI (95% CI = 0.63-0.76). The odds of HHE and IH were 0.69 (95% CI = 0.62-0.76) and 0.58 (95% CI = 0.49-0.68) respectively for 1 SD increase in DDI. The adjusted probability of DD was 32% (95% CI = 27-36%) for cows with mean DDI value of 0, while it was 24% (95% CI = 20-29%) in cows with a DDI value of +1. Sire DDI breeding values were standardized in the same way and then binned into terciles creating an ordinal variable representing bulls of high, medium, and low genetic merit for DD resistance. The daughters of low genetic merit bulls were at 2.05 (95% CI = 1.60-2.64), 1.96 (95% CI = 1.53-2.50), and 2.85 (95% CI = 1.64-5.16) times greater odds of being affected by DD, HHE, and IH, respectively, compared with the daughters of high genetic merit bulls. The results of this study highlight the potential of digital dermatitis genetic indexes to aid herd management of DD, and suggest that breeding for resistance to DD, alongside environmental and management control practices, could reduce the prevalence of the disease.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Animais , Bovinos , Dermatite Digital/genética , Doenças dos Bovinos/genética , Feminino , Estudos Prospectivos , Hiperplasia/veterinária , Doenças do Pé/veterinária , Doenças do Pé/genética , Genótipo , Casco e Garras/patologiaRESUMO
Digital dermatitis (DD) is a painful infectious disease in dairy cattle that causes ulcerative lesions of the skin just above the coronary band, mainly of the hind legs. Estimates for DD prevalence at cow level in the Netherlands range from 20% to 25%. In this study, risk factors for the various stages of DD were identified and quantified. The hind legs of 6766 cows on 88 farms were scored by trained interns, using the M-scoring system (M0-M4.1). Farms in this study were a convenience sample, based on the prevalence of DD as recorded at the latest herd trim, geographical location and willingness of the farmers to participate. A survey with questions about cow environment and herd management was conducted by the intern at the day of scoring. The data were collected between August 2017 and January 2018. DD was found on 38.6% of the scored legs; 49.8% of the cows had DD on at least one leg and M4 was the most frequent stage (20.9%). Not removing manure on a regular basis resulted in lower odds for M2, M4 and M4.1 compared to cleaning by automatic scrapers ten times a day or more (odds ratio [OR]= 0.16, 0.49 and 0.18, respectively). The odds for M2 and M4 lesions were higher in cows aged 3-5 years than in first-calved cows (OR> 1.5 and > 1.7, respectively). Rubber flooring in the passageways resulted in lower odds for both M1 and M2 (OR, 0.06 and 0.32, respectively). Prophylactic use of footbaths treatment with an alternative active compound resulted in significant higher odds for M4 lesions than formalin and a combination of formalin and copper sulphate (OR= 1.69 and 2.04 respectively). The odds for an M4.1 lesion were lower in cows from smaller herds (n = 50-100) compared to large herds (n >100; OR= 0.67).
Assuntos
Doenças dos Bovinos , Dermatite Digital , Feminino , Bovinos , Animais , Lactação , Dermatite Digital/epidemiologia , Dermatite Digital/prevenção & controle , Dermatite Digital/patologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/patologia , Indústria de Laticínios/métodos , Fatores de Risco , FormaldeídoRESUMO
Our objective was to assess potassium monopersulfate as a disinfectant used in footbath to control digital dermatitis (DD) in dairy cows. We hypothesized that a potassium monopersulfate solution would control DD. A 180-day randomized negative controlled trial was conducted in a 265-Holstein free-stall facility. Throughout the trial, foot bathing was performed bi-weekly using a split (left vs. right feet) footbath: one tub filled with 1% potassium monopersulfate (treatment), the other with tap water (control). Digital dermatitis lesions were scored during trimming chute examinations of the unwashed hind heels every 90 days using the modified M-scoring system. Digital dermatitis lesions were re-categorized into four variables: 1) inactive; 2) active; 3) any; 4) inactive or absence of DD lesions. Three longitudinal outcomes were characterized: risks of 1) developing a DD lesion; 2) reactivating an inactive DD lesion; 3) development of an inactive or the absence of the DD lesion. A generalized linear model was used to compare the variables and longitudinal outcomes between treated and control groups. Prevalence of active DD lesions increased from 12.5% to 39.9% between days 0 and 90. This significant increase in prevalence justified the discontinuation of the study on day 90 for ethical reasons. There was no statistical difference between treated and control groups for the first outcome (RR: 1.0; 95% CI: 0.62, 1.7), the second outcome (RR: 1.0; 95% CI: 0.62,-1.7); or the third outcome (RR: 0.88; 95% CI: 0.37, 2.1). A 1% potassium monopersulfate footbath solution appears ineffective to control DD in this study.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Doenças do Pé , Casco e Garras , Compostos de Potássio , Sulfatos , Feminino , Bovinos , Animais , Lactação , Dermatite Digital/tratamento farmacológico , Dermatite Digital/prevenção & controle , Dermatite Digital/epidemiologia , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/epidemiologia , Casco e Garras/patologia , Indústria de Laticínios , Doenças do Pé/prevenção & controle , Doenças do Pé/veterináriaRESUMO
Digital dermatitis (DD) is a skin disease in cattle characterized by painful inflammatory ulcerative lesions in the feet, mostly associated with local colonization by Treponema spp., including Treponema phagedenis. The reason why most DD lesions remain actively inflamed and progress to chronic conditions despite antibiotic treatment remains unknown. Herein, we show an abundant infiltration of proinflammatory (CD14highCD16low) monocytes/macrophages in active DD lesions, a skin response that was not mitigated by topical treatment with oxytetracycline. The associated bacterium, T. phagedenis, isolated from DD lesions in cattle, when injected subcutaneously into mice, induced abscesses with a local recruitment of Ly6G+ neutrophils and proinflammatory (Ly6ChighCCR2+) monocytes/macrophages, which appeared at infection onset (4 days post challenge) and persisted for at least 7 days post challenge. When exploring the ability of macrophages to regulate inflammation, we showed that bovine blood-derived macrophages challenged with live T. phagedenis or its structural components secreted IL-1ß via a mechanism dependent on the NLRP3 inflammasome. This study shows that proinflammatory characteristics of monocytes/macrophages and neutrophils dominate active non-healing ulcerative lesions in active DD, thus likely impeding wound healing after antibiotic treatment.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Animais , Bovinos , Camundongos , Dermatite Digital/microbiologia , Monócitos , Treponema , Abscesso , Doenças dos Bovinos/microbiologia , AntibacterianosRESUMO
The present study aimed to use detailed phenotyping for the claw disorder digital dermatitis (DD) considering specific DD stages in 2 housing systems (conventional cubicle barns [CON] and compost-bedded pack barns [CBPB]) to infer possible genotype × housing system interactions. The DD stages included 2,980 observations for the 3 traits DD-sick, DD-acute, and DD-chronic from 1,311 Holstein-Friesian and 399 Fleckvieh-Simmental cows. Selection of the 5 CBPB and 5 CON herds was based on a specific protocol to achieve a high level of herd similarity with regard to climate, feeding, milking system, and location, but with pronounced housing-system differences. Five other farms had a "mixed system" with 2 subherds, one representing CBPB and the other one CON. The CBPB system was represented by 899 cows (1,530 observations), and 811 cows (1,450 observations) represented the CON system. The average disease prevalence was 20.47% for DD-sick, 13.88% for DD-acute, and 5.34% for DD-chronic, with a higher prevalence in CON than in CBPB. After quality control of 50K genotypes, 38,495 SNPs from 926 cows remained for the ongoing genomic analyses. Genetic parameters for DD-sick, DD-acute, and DD-chronic were estimated by applying single-step approaches for single-trait repeatability animal models considering the whole dataset, and separately for the CON and CBPB subsets. Genetic correlations between same DD traits from different housing systems, and between DD-sick, DD-chronic, and DD-acute, were estimated via bivariate animal models. Heritabilities based on the whole dataset were 0.16 for DD-sick, 0.14 for DD-acute, and 0.11 for DD-chronic. A slight increase of heritabilities and genetic variances was observed in CON compared with the "well-being" CBPB system, indicating a stronger genetic differentiation of diseases in a more challenging environment. Genetic correlations between same DD traits recorded in CON or CBPB were close to 0.80, disproving obvious genotype × housing system interactions. Genetic correlations among DD-sick, DD-acute and DD-chronic ranged from 0.58 to 0.81. SNP main effects and SNP × housing system interaction effects were estimated simultaneously via GWAS, considering only the phenotypes from genotyped cows. Ongoing annotations of potential candidate genes focused on chromosomal segments 100 kb upstream and downstream from the significantly associated candidate SNP. GWAS for main effects indicated heterogeneous Manhattan plots especially for DD-acute and DD-chronic, indicating particularities in disease pathogenesis. Nevertheless, a few shared annotated potential candidate genes, that is, METTL25, AFF3, PRKG1, and TENM4 for DD-sick and DD-acute, were identified. These genes have direct or indirect effects on disease resistance or immunology. For the SNP × housing system interaction, the annotated genes ASXL1 and NOL4L on BTA 13 were relevant for DD-sick and DD-acute. Overall, the very similar genetic parameters for the same traits in different environments and negligible genotype × housing system interactions indicate only minor effects on genetic evaluations for DD due to housing-system particularities.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Estudo de Associação Genômica Ampla , Genótipo , Animais , Bovinos , Feminino , Doenças dos Bovinos/genética , Dermatite Digital/genética , Estudo de Associação Genômica Ampla/veterinária , Fenótipo , Abrigo para Animais , Polimorfismo de Nucleotídeo ÚnicoRESUMO
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.
Assuntos
Doenças dos Bovinos , Dermatite , Dermatite Digital , Doenças do Pé , Úlcera do Pé , Casco e Garras , Úlcera Cutânea , Bovinos/genética , Animais , Doenças do Pé/genética , Doenças do Pé/veterinária , Estudo de Associação Genômica Ampla/veterinária , Dermatite Digital/genética , Úlcera/veterinária , Hiperplasia/veterinária , Doenças dos Bovinos/genética , Fenótipo , Úlcera do Pé/veterinária , Genômica , Dermatite/veterinária , Hemorragia/veterinária , América do NorteRESUMO
The source of infection of digital dermatitis (DD), an infectious lameness condition, is still uncertain. In this cross-sectional study, we aimed to identify potential reservoirs of DD bacteria in dairy cattle body sites with different stages of the disease and farm environments. We collected skin swabs from 85 dairy cows from 5 herds, 3 with and 2 without DD, from foot, hock, and udder cleft skin (with lesions or not), saliva, urine, and feces. We also obtained environmental samples. Real-time quantitative PCR targeted Treponema phagedenis, Treponema medium, Treponema pedis, Porphyromonas levii, Bacteroides pyogenes, Fusobacterium necrophorum, and Fusobacterium mortiferum. Digital dermatitis-associated Treponema spp. were exclusively detected in DD-affected herds in DD-foot and other skin lesions, healthy skin, saliva, and environmental samples. In contrast, the non-Treponema spp. were found in samples from both DD-negative and affected herds. As expected, DD lesions had higher bacterial loads than healthy skin. Interestingly, similar counts were observed in udder cleft lesions, indicating a potential opportunistic behavior on compromised skin. None of the targeted species were detected in fecal samples, but P. levii, B. pyogenes, and F. necrophorum were detected in urine. All 7 species were detected in saliva, although in low quantities. No associations were observed between the presence of each bacterial species in DD lesions and urine; however, there was an association between the presence of DD-Treponema spp. in lesions and saliva, hock, and udder skin. Feces and urine do not seem to be a DD bacteria primary source, but saliva and other skin lesions may play a role. Longitudinal studies would improve our understanding of DD-associated bacteria's transient or persistent presence in these sites. Investigating the sources of DD-associated bacteria will guide future interventions to minimize bacterial shedding and transmission, ultimately more effectively reducing bacterial load, transmission, and sources of infection in dairy herds.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Dermatopatias , Bovinos , Feminino , Animais , Dermatite Digital/microbiologia , Estudos Transversais , Fazendas , Treponema , Bactérias , Dermatopatias/veterinária , Doenças dos Bovinos/microbiologiaRESUMO
Claw lesions in dairy cows contribute significantly to lameness, causing distress and discomfort for affected cows and raising welfare concerns. Despite increased awareness, lameness incidence continues to rise. Defining and recording claw traits are particularly problematic. In South Africa (SA), claw data is limited to paper-based records kept by private hoof trimmers. This research analysed claw-trimming data from five dairy farms over 6 years to examine the occurrence and recording of claw lesions in SA Holstein cattle. Lesion identification followed the Claw Lesion Identification in Dairy Cattle brochure. Among the recorded lesions, digital dermatitis (DD) had the highest prevalence (64.02%), followed by sole ulcers (SU; 8.59%), white line disease (WLD; 6.27%), and sole haemorrhage (SH; 4.28%), and most lesions occurred in the rear feet. Chi-square tests and correspondence analysis (CA) were employed to explore the relationships between lesions, feet, and housing. Results indicated that the prevalence of SU and SH showed high similarity for foot and lesion association, and that these were more highly associated with the rear feet. Additionally, the prevalence of DD and interdigital phlegmon were strongly associated, and closely associated with SU, and all these lesions were associated with both dirt lot and free-stall housing systems. CA further confirmed a close association between WLD and SH, and the prevalence of these lesions in the combination housing system. Results of this study highlight the complexity of lesion data and that specific associations between lesions could lead to simplifying the recording thereof. Consolidating the most informative claw lesions into categories will aid in the practical prevention, management, and treatment of lameness on-farm.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Doenças do Pé , Casco e Garras , Feminino , Animais , Bovinos , Doenças do Pé/epidemiologia , Doenças do Pé/veterinária , Casco e Garras/patologia , Coxeadura Animal/epidemiologia , Coxeadura Animal/etiologia , África do Sul/epidemiologia , Doenças dos Bovinos/prevenção & controle , Dermatite Digital/complicações , Indústria de LaticíniosRESUMO
INTRODUCTION: Diseases of the digits often occur in cattle on larger cattle mountain pastures. In the late spring 2020, at the time of the ascent of 1554 cattle to 11 high altitude alpine pastures in the Lower Engadine region, lesions in the area of the digits were clinically assessed and documented. 254 cattle were of non-cantonal and 1300 of local origin (Lower Engadine; postal code CH-75XX). Skin lesions in the area of the digits, identified as digital dermatitis (DD; Mortellaro's disease), were further classified according to the DD scoring system. Nonspecific skin lesions with clinical evidence of granulation tissue formation were termed chronic penetrating skin lesions (CPSL). At the end of the alpine pasturing season, in the early fall (descent of cattle from the alpine pastures), the procedure was repeated, and biopsies were taken from randomly selected cattle with CPSL. Digital dermatitis lesions were found in 34 of 1551 cattle at ascent, but no case of CPSL was found at that time. At descent, 19 of 1529 cattle had DD lesions and 88 cattle had CPSL. The clinical appearance of the CPSL was consistent with chronic skin lesions caused by penetrating skin lacerations. Histologically, the majority of the CPSL were classified as chronic hyperplastic dermatitis with granulation tissue formation. In all CPSL biopsies examined by PCR, Fusobacterium necrophorum and Porphyromonas levii, but neither Dichelobacter nodosus nor the tested Treponema species were detected. Fluorescence in situ hybridization revealed a negative result for Treponema species in all biopsies. In the regression analysis, cattle in the age group of 365 to 730 days had an increased risk for the presence of CPSL compared to the age group of 160 to 365 days (odds ratio (OR) = 4,95; confidence interval (CI) = 1,97-12,43). Holstein cattle had an increased risk of developing CPSL compared to Brown cattle (OR = 2,92; CI = 1,46-5,86) and cattle of non-cantonal origin showed a massively higher risk compared to local cattle (OR = 10,59; CI = 5,79 - 19,37). The statistically significant associations found in the present study can be taken into account in the selection of animals for summer pasturing on high altitudes in the future in order to reduce the prevalence of CPSL and consequently reduce the antimicrobial use. Spread of DD during the alpine pasturing season within the cattle groups examined was not found.
INTRODUCTION: Des atteintes aux onglons sont souvent observées sur les grands alpages de bovins. Des altérations au niveau des onglons ont été examinées cliniquement et répertoriées chez 1554 bovins lors de leur arrivée sur 11 alpages en Basse-Engadine, en provenance d'un autre canton (n = 254) ou de la localité à laquelle l'alpage appartenait (n = 1300, numéro postal 75XX), au moment de la montée à l'alpage en 2020. Les altérations cutanées diagnostiquées comme dermatite digitale (DD; maladie de Mortellaro) ont de plus été classifiées selon les scores en usage pour la DD. Les lésions cutanées non-spécifiques présentant une formation de tissu de granulation ont été enregistrées comme lésions cutanées perforantes chroniques (LCPC). La procédure a été répétée lors de la désalpe et une biopsie a été prise de chez des animaux présentant des LCPC choisis au hasard. Les caractéristiques de la topographie de l'alpage et celles du sol, ainsi que la densité d'occupation ont été enregistrées pour chaque alpage. Des lésions de DD ont été constatées chez 34 des 1551 bovins lors de la montée à l'alpage, mais aucun cas de LCPC n'a été observé. Lors de la désalpe, 19 des 1551 bovins présentaient des lésions de DD et 88 une LCPC. L'apparence des LCPC correspondait à des lésions cutanées chroniques après une blessure perforante de la peau. À l'histologie, il s'agissait la plupart du temps d'une dermatite chronique hyperplastique avec formation de tissu de granulation. Fusobacterium necrophorum et Porphyromonas levii ont été mis en évidence dans toutes les biopsies de LCPC soumises à une analyse par PCR, mais ni Dichelobacter nodosus ni les Treponema spp. recherchées n'ont été mis en évidence. L'hybridation in-situ en fluorescence était négative pour les tréponèmes dans toutes les biopsies. Selon les résultats d'une analyse de régression, les génisses âgées de 366 à 730 jours avaient un risque augmenté (Odds Ratio (OR) = 4,95; intervalle de confiance (IC) = 1,97 12,43) de présenter une LCPC en comparaison avec le groupe d'âge de 161 à 365 jours. Les bovins de race Holstein avaient un risque augmenté de présenter une LCPC en comparaison avec ceux de race grise (OR = 2,92; IC = 1,46 5,86), et les animaux en provenance d'autres cantons présentaient un risque massivement plus élevé que le cheptel local (OR = 10,59; IC = 5,79 19,37). Aucune différence significative n'a été observée dans la topographie ou dans la densité d'occupation entre les alpages avec et sans cas de LCPC. Les associations statistiquement significatives constatées dans cette étude peuvent être prises en compte à l'avenir lors de la sélection d'animaux pour l'alpage, dans le but de réduire la prévalence de LCPC, de diminuer la quantité d'antibiotiques administrés et d'améliorer le bien-être animal. Une propagation de la DD pendant la saison d'alpage n'a pas été constatée dans les groupes de bovins inclus dans l'étude.
Assuntos
Doenças dos Bovinos , Dermatite Digital , Bovinos , Animais , Dermatite Digital/microbiologia , Hibridização in Situ Fluorescente/veterinária , Suíça/epidemiologia , Doenças dos Bovinos/patologia , Treponema/genética , Fatores de RiscoRESUMO
BACKGROUND: Footbaths can be used to manage digital dermatitis (DD), a common cause of lameness in dairy cattle. Copper sulfate and chelated copper-zinc (CZS) solutions in footbaths are potentially harmful to the environment. HYPOTHESIS/OBJECTIVES: To determine if a quaternary ammonium salt-based disinfectant (QASD) footbath is as effective as a chelated CZS solution in controlling DD in dairy cows. ANIMALS: Fifty-one lactating Holstein cows were randomly assigned to one of two treatment groups, with DD status based on the M-stage scoring system and locomotion score balanced between treatment groups. MATERIALS AND METHODS: The groups were treated with a 1% QASD or a 2.5% chelated CZS. Footbaths were performed once per week for 15 weeks. Logistic regression was used to analyse clinical improvement. All cows received appropriate medical treatment for DD and other hoof diseases. RESULTS: Clinical improvement rates were 67% in the QASD group and 38% in the CZS group (p = 0.03). Logistic regression analysis showed that the odds (95% confidence interval) for clinical improvement rate in the CZS group were 0.30 (0.095-0.948) times that of the QASD group (p = 0.04). The M0 score in the QASD and CZS groups increased significantly (p < 0.05) at the end of the 15 week study period. In the QASD group, the proportion of M2, M3 and M4 scores were significantly decreased (p < 0.05). CONCLUSION AND CLINICAL RELEVANCE: Over a 15 week period, QASD for footbathing was associated with a lower prevalence of active DD lesions than when using CZS.