The cost of different types of lameness in dairy cows calculated by dynamic programming

A Review of the Relationship Between Hoof Trimming and Dairy Cattle Welfare

A narrative integrative review on the evidence for hoof trimming found 16 articles on efficacy, frequency, and associations with behavior and physiologic parameters. Review of these studies revealed (1) hoof trimming is associated with behavior and physiologic changes; (2) increasing the frequency of hoof trimming seems to decrease the incidence of hoof lesions; (3) there is limited research to support any particular technique; and (4) descriptions of the hoof trimming techniques used is inadequate in most articles. To increase scientific support for hoof trimming practices, current knowledge gaps in technique, timing, and frequency of hoof trimming need to be addressed.

Producer estimates of prevalence and perceived importance of lameness in dairy herds with tiestalls, freestalls, and automated milking systems

Lameness is one of the most important welfare and productivity concerns in the dairy industry. Our objectives were to obtain producers' estimates of its prevalence and their perceptions of lameness, and to investigate how producers monitor lameness in tiestall (TS), freestall with milking parlor (FS), and automated milking system (AMS) herds. Forty focal cows per farm in 237 Canadian dairy herds were scored for lameness by trained researchers. On the same day, the producers completed a questionnaire. Mean herd-level prevalence of lameness estimated by producers was 9.0% (±0.9%; ±SE), whereas the researchers observed a mean prevalence of 22.2% (±0.9%). Correlation between producer- and researcher-estimated lameness prevalence was low (r = 0.19) and mean researcher prevalence was 1.6, 1.8, and 4.1 times higher in AMS, FS, and TS farms, respectively. A total of 48% of producers thought lameness was a moderate or major problem in their herds (TS = 34%; AMS =53%; FS = 59%). One third of producers considered lameness the highest ranked health problem they were trying to control, whereas two-thirds of producers (TS = 43%; AMS = 63%; FS = 71%) stated that they had made management changes to deal with lameness in the past 2 yr. Almost all producers (98%) stated they routinely check cows to identify new cases of lameness; however, 40% of producers did not keep records of lameness (AMS = 24%; FS = 23%; TS = 60%). A majority (69%) of producers treated lame cows themselves immediately after detection, whereas 13% relied on hoof-trimmer or veterinarians to plan treatment. Producers are aware of lameness as an issue in dairy herds and almost all monitor lameness as part of their daily routine. However, producers underestimate lameness prevalence, which highlights that lameness detection continues to be difficult in in all housing systems, especially in TS herds. Training to improve detection, record keeping, identification of farm-specific risk factors, and treatment planning for lame cows is likely to help decrease lameness prevalence.

Associations between biosecurity practices and bovine digital dermatitis in Danish dairy herds

The relationship between biosecurity and digital dermatitis (DD) was evaluated in 8,269 cows from a convenience sample of 39 freestall dairy herds. The hypothesis was that poor implementation of biosecurity was associated with higher within-herd prevalence of DD. All lactating cows were scored as negative or positive for DD at the hind legs during milking in the milking parlor. Information about biosecurity was obtained through questionnaires addressed to farmers, on-farm observations, and information from the Danish Cattle Database (www.seges.dk). These assessment tools covered potential infection sources of DD pathogens to susceptible cows (e.g., via animals, humans, manure, vehicles, equipment, and facilities). External and internal biosecurity measures were explanatory variables in 2 separate logistic regression models, whereas within-herd DD prevalence was the outcome. Overall DD prevalence among cows and herds were 24 and 97%, respectively; the within-herd DD prevalence ranged from 0 to 56%. Poor external biosecurity measures associated with higher prevalence of DD were recent animal purchase, access to pasture, lack of boots available for visitors, farm staff working at other dairy farms as well, hoof trimming without a professional attending, and animal transporters having access to cattle area. For internal biosecurity, higher DD prevalence were associated with infrequent hoof bathing, manure scraping less than 8 times a day, manure removal direction from cows to heifers, animal pens' exit without water hoses, manure-handling vehicle used in other activities, and water troughs contaminated with manure. These findings showed that improvements on biosecurity may be beneficial for controlling DD in dairy herds. The study is relevant for farmers facing problems with DD, as well as hoof trimmers, advisors, and veterinarians, who can use the results for optimized recommendations regarding biosecurity in relation to DD. Furthermore, our results might be considered by future studies investigating DD pathogen reservoirs and transmission routes.

Estimating US dairy clinical disease costs with a stochastic simulation model

A farm-level stochastic model was used to estimate costs of 7 common clinical diseases in the United States: mastitis, lameness, metritis, retained placenta, left-displaced abomasum, ketosis, and hypocalcemia. The total disease costs were divided into 7 categories: veterinary and treatment, producer labor, milk loss, discarded milk, culling cost, extended days open, and on-farm death. A Monte Carlo simulation with 5,000 iterations was applied to the model to account for inherent system variation. Four types of market prices (milk, feed, slaughter, and replacement cow) and 3 herd-performance factors (rolling herd average, product of heat detection rate and conception rate, and age at first calving) were modeled stochastically. Sensitivity analyses were conducted to study the relationship between total disease costs and selected stochastic factors. In general, the disease costs in multiparous cows were greater than in primiparous cows. Left-displaced abomasum had the greatest estimated total costs in all parities ($432.48 in primiparous cows and $639.51 in multiparous cows). Cost category contributions varied for different diseases and parities. Milk production loss and treatment cost were the 2 greatest cost categories. The effect of market prices were consistent in all diseases and parities; higher milk and replacement prices increased total costs, whereas greater feed and slaughter prices decreased disease costs.

Effectiveness of a standardized footbath protocol for prevention of digital dermatitis

A footbath is the most common herd-level approach to control digital dermatitis (DD) in intensive dairy farming. However, wide variation in footbath design and protocols suggests a gap between evidence-based management practices and on-farm implementation. The objective was to evaluate effectiveness of a standardized footbath protocol in decreasing prevalence of active DD lesions in lactating dairy cattle. The protocol was based on current scientific literature, including footbath design and management. The M-stage classification system was used to score DD lesions. Scores were also combined into a simplified scoring system: no lesions (M0), active lesions (M1, M2, and M4.1), and chronic lesions (M3 and M4). A controlled intervention trial was conducted on 9 farms over 22 wk. Each farm served as its own control with data collected for 10 wk before and 12 wk after intervention. A total of 1,978 lactating cattle were assessed biweekly for DD lesions and leg cleanliness in the milking parlor. Lactating cattle were also inspected in the trimming chute at 3 time points: start, intervention, and end of trial. Intervention consisted of implementing an automated footbath that measured 3 m long, 0.50 m wide, held a fluid depth of 0.15 m, along with a weekly footbath protocol using 5% CuSO₄ for 4 consecutive milkings, with footbath content replaced at a maximum of 200 cow passes. Multilevel logistic regression models for repeated measures were used to evaluate effects of the standardized footbath protocol in preventing active DD lesions. For the purpose of analysis, farms' within-herd prevalence of active DD lesions (at baseline) was assessed and categorized as low (<15%) or high (≥15%). Farms with low or high within-herd prevalence of active DD lesions at trial outset had a mean cow-level prevalence of active DD lesions of 8% (range, 2 to 13) and 31% (range, 18 to 43), respectively. At milking parlor inspections, apparent prevalence of active DD lesions decreased from the time of footbath intervention, but this effect interacted with the farms' baseline prevalence of active DD lesions. In that regard, on farms with high prevalence of active DD at baseline, apparent prevalence of active DD lesions decreased after intervention, whereas on farms with low prevalence of active DD at baseline, apparent prevalence of active DD lesions did not change. At the cow level, poor leg cleanliness was associated with higher prevalence of active DD lesions. At trimming chute inspections, prevalence of active DD lesions decreased from start to the end of the trial (22 and 14%, respectively); concurrently, prevalence of feet with no DD lesions (M0) increased (39 and 48%). We concluded that on farms with high DD prevalence, implementation of proper footbath design and improvement of footbathing management will decrease prevalence of active DD lesions and increase prevalence of feet without DD lesions. In addition, improving cow cleanliness will further result in control of active DD lesions.

Validation of the M-stage scoring system for digital dermatitis on dairy cows in the milking parlor

A high prevalence of digital dermatitis (DD) and the benefits of early topical treatment highlight the need for simple tools for routine DD detection. The objective of this study was to determine the accuracy of scoring DD lesions using the 5 M-stage scoring system in the milking parlor compared with the trimming chute as the gold standard. Three observers inspected 3,585 cows and 6,991 hind feet from 9 farms in the milking parlor using a mirror (glued to a plastic kitchen spatula) and a headlamp, followed by inspection in a trimming chute within 5 d. Interobserver agreement for scoring DD in various settings was ≥82% (kappa >0.74; weighted kappa >0.76). At trimming chute inspections, 68% of cows had at least 1 DD lesion, 19% had 1 hind leg affected, and 49% had both hind legs affected. Within-herd DD prevalence ranged from 16 to 81% of cows affected. True within-herd prevalence was 2, 6, 0, 36, and 14% for M1, M2, M3, M4, and M4.1 lesions, respectively. At the foot level, DD prevalence was the same (58%) in the milking parlor and trimming chute inspection, but distribution of M-stages differed. Milking parlor inspection as a means of identifying the presence of DD lesions had a sensitivity of 92% and specificity of 88%, with positive and negative predictive values of 91 and 89%, respectively. Agreement between milking parlor and trimming chute inspections was 73% (kappa = 0.59, weighted kappa = 0.65) for the 5 M-stage scoring system and 90% (kappa = 0.80) if only the presence of a lesion was noted. Test characteristics varied greatly among M-stages, with the highest sensitivity for detecting M4 (82%) and M2 (62%) lesions, and the lowest for detecting M4.1 (20%), M1 (7%), and M3 (0%) lesions. In the milking parlor, 20% of M2 lesions were misclassified as M4.1, 8% of M4 lesions were misclassified as M0, and 68% of M4.1 lesions were misclassified as M4. The majority (87%) of DD lesions were located between the heel bulbs; 10 and 2% of DD lesions affected the interdigital space and the front of the foot, respectively. The sensitivity to detect the presence of a lesion when it occurred between the heel bulbs was 93%, but <67% if it occurred elsewhere on the foot. We concluded that inspection of the rear feet in the milking parlor was an inexpensive and simple method of detecting and scoring DD lesions. If the objective is to determine herd-level DD prevalence and routine monitoring, this method was adequately reliable. However, if the objective is to follow up DD in cows with history of interdigital hyperplasia or to detect M1 or M4.1 lesions, this method was not sufficiently reliable. Although DD scoring in the milking parlor as a routine practice should facilitate early detection, prompt treatment interventions, and herd monitoring, it was not sufficiently reliable to replace definitive identification of M-stages in the trimming chute.

Effect of claw disorders on milk production, fertility, and longevity, and their economic impact in Spanish Holstein cows

The aims of this study were (1) to estimate the phenotypic association between different degrees of severity of claw disorders and production, fertility performance, and longevity in Spanish dairy cattle, and (2) to quantify its economic impact at the animal and herd level. In this study, claw data comprised 108,468 trimmings collected between 2012 and 2014 by 25 trimmers from 804 Holstein dairy herds. The claw disorders considered were the 3 most frequent disorders in Spanish dairy herds: dermatitis (DE), sole ulcer (SU), and white line disease (WL). The presence of SU or WL was associated with a significant decrease in milk production and was more important in cows in second or later lactations. A severe lesion of SU or WL lead to twice the milk losses associated with a mild lesion, ranging from 1.47 to 2.66kg/d of energy-corrected milk. The presence of SU or WL during the early lactation period was associated with more days open, fewer inseminations to get pregnant, and longer calving to first service interval (4.83 and 8.0 d longer due to mild and severe lesions of SU, respectively, and 4.94 and 17.43 d longer due to mild and severe lesions of WL, respectively). The occurrence of a case of SU or WL in first lactation had a significant effect on longevity, with severe lesions reducing up to 71 d of productive life. The cost of a mild lesion ranged from $53 to $232 per affected cow and year, whereas the cost of a severe lesion ranged from $402 to $622 per affected cow and year. The annual costs per cow for DE, SU, and WL were $10.80, $50.9, and $43.2, respectively. An average herd with 64 cows had an extra expenditure of $691/yr due to DE, $3,256/yr due to SU, and $2,765/year due to WL. Milk losses, longer calving intervals, and premature culling contributed to more than half of the costs. Therefore, providing this information to farmers could help decide on strategies to reduce the incidence of claw disorders on the farm.

The DD Check App for prevention and control of digital dermatitis in dairy herds

Digital dermatitis (DD) is the most important infectious claw disease in the cattle industry causing outbreaks of lameness. The clinical course of disease can be classified using 5 clinical stages. M-stages represent not only different disease severities but also unique clinical characteristics and outcomes. Monitoring the proportions of cows per M-stage is needed to better understand and address DD and factors influencing risks of DD in a herd. Changes in the proportion of cows per M-stage over time or between groups may be attributed to differences in management, environment, or treatment and can have impact on the future claw health of the herd. Yet trends in claw health regarding DD are not intuitively noticed without statistical analysis of detailed records. Our specific aim was to develop a mobile application (app) for persons with less statistical training, experience or supporting programs that would standardize M-stage records, automate data analysis including trends of M-stages over time, the calculation of predictions and assignments of Cow Types (i.e., Cow Types I-III are assigned to cows without active lesions, single and repeated cases of active DD lesions, respectively). The predictions were the stationary distributions of transitions between DD states (i.e., M-stages or signs of chronicity) in a class-structured multi-state Markov chain population model commonly used to model endemic diseases. We hypothesized that the app can be used at different levels of record detail to discover significant trends in the prevalence of M-stages that help to make informed decisions to prevent and control DD on-farm. Four data sets were used to test the flexibility and value of the DD Check App. The app allows easy recording of M-stages in different environments and is flexible in terms of the users' goals and the level of detail used. Results show that this tool discovers trends in M-stage proportions, predicts potential outbreaks of DD, and makes comparisons among Cow Types, signs of chronicity, scorers or pens. The DD Check App also provides a list of cows that should be treated augmented by individual Cow Types to help guide treatment and determine prognoses. Producers can be proactive instead of reactive in controlling DD in a herd by using this app. The DD Check App serves as an example of how technology makes knowledge and advice of veterinary epidemiology widely available to monitor, control and prevent this complex disease.

Invited review: Opportunities for genetic improvement of metabolic diseases

Metabolic disorders are disturbances to one or more of the metabolic processes in dairy cattle. Dysfunction of any of these processes is associated with the manifestation of metabolic diseases or disorders. In this review, data recording, incidences, genetic parameters, predictors, and status of genetic evaluations were examined for (1) ketosis, (2) displaced abomasum, (3) milk fever, and (4) tetany, as these are the most prevalent metabolic diseases where published genetic parameters are available. The reported incidences of clinical cases of metabolic disorders are generally low (less than 10% of cows are recorded as having a metabolic disease per herd per year or parity/lactation). Heritability estimates are also low and are typically less than 5%. Genetic correlations between metabolic traits are mainly positive, indicating that selection to improve one of these diseases is likely to have a positive effect on the others. Furthermore, there may also be opportunities to select for general disease resistance in terms of metabolic stability. Although there is inconsistency in published genetic correlation estimates between milk yield and metabolic traits, selection for milk yield may be expected to lead to a deterioration in metabolic disorders. Under-recording and difficulty in diagnosing subclinical cases are among the reasons why interest is growing in using easily measurable predictors of metabolic diseases, either recorded on-farm by using sensors and milk tests or off-farm using data collected from routine milk recording. Some countries have already initiated genetic evaluations of metabolic disease traits and currently most of these use clinical observations of disease. However, there are opportunities to use clinical diseases in addition to predictor traits and genomic information to strengthen genetic evaluations for metabolic health in the future.

The effect of lameness on the environmental performance of milk production by rotational grazing

Dairy production leads to significant environmental impacts and increased production will only be feasible if the environmental performance at farm level permits a sustainable milk supply. Lameness is believed to become more prevalent and severe as herd sizes increase, and can significantly reduce milk output per cow while not influencing other attributes of the production system. The objective of this work was to quantify the effect of lameness on the environmental performance of a typical grazed grass dairy farm and evaluate the theoretical value of sensor-based real-time lameness management. Life cycle assessment was used to compare a typical baseline farm with scenarios assuming increased lameness severity and prevalence. It was found that lameness could increase the farm level global warming potential, acidification potential, eutrophication potential and fossil fuel depletion by 7-9%. As increased herd sizes will increase cow: handler ratio, this result was interpreted to suggest that the use of sensors and information and communication technology for lameness detection could improve management on dairy farms to reduce the adverse impact on environmental performance that is associated with lameness.

Patologías podales en ganado lechero y feedlot del partido de Tandil, provincia de Buenos Aires, Argentina

<p>Las patologías podales del bovino son multicausales, incluyendo alta producción, estrés, nutrición, causas ambientales, infecciosas, genéticas, razas, estado fisiológico y comportamiento tanto animal como humano. Están adquiriendo gran importancia debido a la intensificación  de la producción. El objetivo del presente trabajo fue determinar la prevalencia de enfermedades podales en explotaciones lecheras y en comparar ambos tipos de explotación en la región de Tandil, Buenos Aires, Argentina. Se evaluaron 24 tambos en 2005 y un en 2013 en busca de patologías podales. Los animales que presentaron claudicación se separaron del rodeo y se revisaron. Se calculó la prevalencia bruta y por patologías de mayor presentación en ambos tipos de producción y además proporción según miembro afectado. Se estimaron diferencias entre las prevalencias de cada tipo de producción por medio de Chi cuadrado (lt;0,05) y razón de prevalencias. La prevalencia en los 12132 animales lecheros fue del 2,71% y en los 14500 de <em>feedlot</em> del 0,57% (Razón de prevalencia=4,73 (IC95%=3,72–6,02). La prevalencia de traumatismos en <em>feedlot</em> fue del 0,17% y en tambos 0,016% (p&lt;0,05); dermatitis digital (tambo 0,69%, <em>feedlot</em> 0,13%; p&lt;0,05) e interdigital (tambos 0,81%, 0,1%; lt;0,05). En ambas producciones los miembros más afectados fueron los posteriores (90,4% y 88,1% tambos). La baja prevalencia en podría deberse a la baja edad de los animales. En los animales de hay significativamente más prevalencia en traumatismos que en tambos, mientras que en éstos hay más dermatitis digital e interdigital.</p>

Digital dermatitis: Natural lesion progression and regression in Holstein dairy cattle over 3 years

Bovine digital dermatitis (DD) is a leading cause of lameness in dairy cattle in the United States, with prevalence estimates as high as 30%. Whereas clinical lesions have been well described, little is known about the morphologic changes that are associated with the early stages of lesion development from normal skin to clinical lesions. This study used the Iowa DD scoring system to evaluate the epidemiology of natural lesion development by digitally photographing the rear legs of a cohort of dairy cows over a 3-yr period. Sixty-one adult Holstein dairy cows were monitored for 1,032 cow foot-months. The incidence rate of lesion development was 4 lesions per 100 cow foot-months, with the average time for a lesion to develop being 133 d. Whereas 20% of the 1,678 foot observations exhibited clinical DD lesions, an additional 55% of all observations exhibited preclinical stage 1 and 2 lesions that were indicative of DD lesion development. Utilizing the dichotomous categorization of preclinical lesions in the Iowa DD scoring system, it was found that first-lactation heifers had a higher rate of the thickened and crusted "B" type lesions, whereas the ulcerative "A" type lesions were more likely to be identified in multiparous animals. For clinical DD lesions that received topical treatment, scoring of the post-treatment lesions using the Iowa DD scoring system was found to be useful in prognosticating both the risk of recrudescence and the time until recrudescence. Systemic disease, systemic antibiotic therapy, and periparturient stress were not associated with an increase or decrease in DD lesion scores. Treatment with a single topical tetracycline wrap was associated with a significant decrease (-1.17) in DD lesion score. The results of this study demonstrate that the complex morphologic changes associated with digital dermatitis can be readily classified using the Iowa DD scoring system and the scores can be used to predict and monitor the effects of treatment and prevention measures.

Lameness Prevalence and Risk Factors in Large Dairy Farms in Upstate New York. Model Development for the Prediction of Claw Horn Disruption Lesions

The main objectives of this prospective cohort study were a) to describe lameness prevalence at drying off in large high producing New York State herds based on visual locomotion score (VLS) and identify potential cow and herd level risk factors, and b) to develop a model that will predict the probability of a cow developing claw horn disruption lesions (CHDL) in the subsequent lactation using cow level variables collected at drying off and/or available from farm management software. Data were collected from 23 large commercial dairy farms located in upstate New York. A total of 7,687 dry cows, that were less than 265 days in gestation, were enrolled in the study. Farms were visited between May 2012 and March 2013, and cows were assessed for body condition score (BCS) and VLS. Data on the CHDL events recorded by the farm employees were extracted from the Dairy-Comp 305 database, as well as information regarding the studied cows’ health events, milk production, and reproductive records throughout the previous and subsequent lactation period. Univariable analyses and mixed multivariable logistic regression models were used to analyse the data at the cow level. The overall average prevalence of lameness (VLS > 2) at drying off was 14%. Lactation group, previous CHDL, mature equivalent 305-d milk yield (ME305), season, BCS at drying off and sire PTA for strength were all significantly associated with lameness at the drying off (cow-level). Lameness at drying off was associated with CHDL incidence in the subsequent lactation, as well as lactation group, previous CHDL and ME305. These risk factors for CHDL in the subsequent lactation were included in our predictive model and adjusted predicted probabilities for CHDL were calculated for all studied cows. ROC analysis identified an optimum cut-off point for these probabilities and using this cut-off point we could predict CHDL incidence in the subsequent lactation with an overall specificity of 75% and sensitivity of 59%. Using this approach, we would have detected 33% of the studied population as being at risk, eventually identifying 59% of future CHDL cases. Our predictive model could help dairy producers focusing their efforts on CHDL reduction by implementing aggressive preventive measures for high risk cows.

Bovine digital dermatitis: Current concepts from laboratory to farm

Bovine digital dermatitis (DD) is a severe infectious disease causing lameness in dairy cattle worldwide and is an important ruminant welfare problem that has considerable economic issues. Bovine DD is endemic in many regions worldwide and it is important to understand this major disease so that effective control strategies can be identified. There is substantial evidence that specific treponeme phylotypes play an important causative role in bovine DD. This review considers current research, including DD Treponema spp. investigations, associated DD pathobiology, and current and potential treatment and control options. Epidemiological data, alongside new microbiological data, help delineate important transmission routes and reservoirs of infection that allow effective interventions to be identified. Better on-farm housing hygiene, pasture access, routine footbathing and claw trimming with disinfected equipment need to be implemented to significantly reduce the incidence of DD. There is a paucity of peer reviewed research into both commonly used and novel treatments. In vitro antimicrobial susceptibility studies of DD treponemes and effective treatment of human treponematoses clearly indicate that antibiotics frequently selected for DD treatments are not the most efficacious. Whilst there are understandable concerns over milk withdrawal times in dairy cattle, more needs to be done to identify, license and implement more appropriate antibiotic treatments, since continued overuse of less efficacious antibiotics, applied incorrectly, will lead to increased disease recurrence and transmission. More research is needed into methods of preventing DD that circumvent the use of antibiotics, including vaccination and transmission blocking studies, to reduce or hopefully eradicate DD in the future.

Predictive models of lameness in dairy cows achieve high sensitivity and specificity with force measurements in three dimensions

Lameness remains a significant cause of production losses, a growing welfare concern and may be a greater economic burden than clinical mastitis . A growing need for accurate, continuous automated detection systems continues because US prevalence of lameness is 12·5% while individual herds may experience prevalence's of 27·8–50·8%. To that end the first force-plate system restricted to the vertical dimension identified lame cows with 85% specificity and 52% sensitivity . These results lead to the hypothesis that addition of transverse and longitudinal dimensions could improve sensitivity of lameness detection. To address the hypothesis we upgraded the original force plate system to measure ground reaction forces (GRFs) across three directions. GRFs and locomotion scores were generated from randomly selected cows and logistic regression was used to develop a model that characterised relationships of locomotion scores to the GRFs. This preliminary study showed 76 variables across 3 dimensions produced a model with greater than 90% sensitivity, specificity, and area under the receiver operating curve (AUC). The result was a marked improvement on the 52% sensitivity, and 85% specificity previously observed with the 1 dimensional model  or the 45% sensitivities reported with visual observations. Validation of model accuracy continues with the goal to finalise accurate automated methods of lameness detection.

Alterations of Innate Immunity Reactants in Transition Dairy Cows before Clinical Signs of Lameness

The objectives of this study were to evaluate metabolic and innate immunity alterations in the blood of transition dairy cows before, during, and after diagnosis of lameness during periparturient period. Blood samples were collected from the coccygeal vain once per week before morning feeding from 100 multiparous Holstein dairy cows during -8, -4, disease diagnosis, and +4 weeks (wks) relative to parturition. Six healthy cows (CON) and six cows that showed clinical signs of lameness were selected for intensive serum analyses. Concentrations of interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor (TNF), haptoglobin (Hp), serum amyloid A (SAA), lipopolysaccharide binding protein (LBP), lactate, non-esterified fatty acids (NEFA), and β-hydroxybutyrate (BHBA) were measured in serum by ELISA or colorimetric methods. Health status, DMI, rectal temperature, milk yield, and milk composition also were monitored for each cow during the whole experimental period. Results showed that cows affected by lameness had greater concentrations of lactate, IL-6, and SAA in the serum vs. CON cows. Concentrations of TNF tended to be greater in cows with lameness compared with CON. In addition, there was a health status (Hs) by time (week) interaction for IL-1, TNF, and Hp in lameness cows vs. CON ones. Enhanced serum concentrations of lactate, IL-6, and SAA at -8 and -4 wks before parturition were different in cows with lameness as compared with those of the CON group. The disease was also associated with lowered overall milk production and DMI as well as milk fat and fat-to-protein ratio. In conclusion, cows affected postpartum by lameness had alterations in several serum variables related to innate immunity and carbohydrate metabolism that give insights into the etiopathogenesis of the disease and might serve to monitor health status of transition dairy cows in the near future.

The economic impact of subclinical ketosis at the farm level: Tackling the challenge of over-estimation due to multiple interactions

Subclinical ketosis (SCK) is a major metabolic disorder that affects dairy cows, and its lactational prevalence in Europe is estimated to be at 25%. Nonetheless, few data are available on the economics of SCK, although its management clearly must be improved. With this in mind, this study develops a double-step stochastic approach to evaluate the total cost of SCK to dairy farming. First, all the production and reproduction changes and all the health disorders associated with SCK were quantified using the meta-analysis from a previous study. Second, the total cost of SCK was determined with a stochastic model using distribution laws as input parameters. The mean total cost of SCK was estimated to be Є257 per calving cow with SCK (95% prediction interval (PI): Є72-442). The margin over feeding costs slightly influenced the results. When the parameters of the model are not modified to account for the conclusions from the meta-analysis and for the prevalence of health disorders in the population without SCK, the mean cost of SCK was overestimated by 68%, reaching Є434 per calving cow (95%PI: Є192-676). This result indicates that the total cost of complex health disorders is likely to be substantially overestimated when calculations use raw results from the literature or-even worse-punctual data. Excluding labour costs in the estimation reduced the SCK total cost by 12%, whereas excluding contributors with scarce data and imprecise calibrations (for lameness and udder health) reduced costs by another 18-20% (Є210, 95%PI=30-390). The proposed method accounted for uncertainty and variability in inputs by using distributions instead of point estimates. The mean value and associated prediction intervals (PIs) yielded good insight into the economic consequences of this complex disease and can be easily and practically used by decision makers in the field while simultaneously accounting for biological variability. Moreover, PIs can help prevent the blind use of economic results in the field when only the mean value is considered.

Shotgun Metagenomic Sequencing Reveals Functional Genes and Microbiome Associated with Bovine Digital Dermatitis

Metagenomic methods amplifying 16S ribosomal RNA genes have been used to describe the microbial diversity of healthy skin and lesion stages of bovine digital dermatitis (DD) and to detect critical pathogens involved with disease pathogenesis. In this study, we characterized the microbiome and for the first time, the composition of functional genes of healthy skin (HS), active (ADD) and inactive (IDD) lesion stages using a whole-genome shotgun approach. Metagenomic sequences were annotated using MG-RAST pipeline. Six phyla were identified as the most abundant. Firmicutes and Actinobacteria were the predominant bacterial phyla in the microbiome of HS, while Spirochetes, Bacteroidetes and Proteobacteria were highly abundant in ADD and IDD. T. denticola-like, T. vincentii-like and T. phagedenis-like constituted the most abundant species in ADD and IDD. Recruitment plots comparing sequences from HS, ADD and IDD samples to the genomes of specific Treponema spp., supported the presence of T. denticola and T. vincentii in ADD and IDD. Comparison of the functional composition of HS to ADD and IDD identified a significant difference in genes associated with motility/chemotaxis and iron acquisition/metabolism. We also provide evidence that the microbiome of ADD and IDD compared to that of HS had significantly higher abundance of genes associated with resistance to copper and zinc, which are commonly used in footbaths to prevent and control DD. In conclusion, the results from this study provide new insights into the HS, ADD and IDD microbiomes, improve our understanding of the disease pathogenesis and generate unprecedented knowledge regarding the functional genetic composition of the digital dermatitis microbiome.

First-lactation performance in cows affected by digital dermatitis during the rearing period

The long-term effects of prepartum digital dermatitis (DD) on first-lactation performance were evaluated in a cohort of 719 pregnant heifers. All heifers were followed for a period of 6 mo until calving and classified on the basis of the number of DD events diagnosed during this period as type I, type II, or type III (no DD, one DD event, and multiple DD events, respectively). Health during the initial 60d in milk (DIM), reproductive and hoof health outcomes, and milk production were compared between the 3 heifer type groups. All logistic and linear models were adjusted for age, height, and girth circumference at enrollment, and the type of trace mineral supplementation during the prepartum period. Overall, cows experiencing DD during the rearing period showed worse production and health outcomes compared with healthy heifers during the first lactation. The percentages of assisted calvings, stillbirths, culled before 60 DIM, and diseased cows during the fresh period were numerically higher in type III cows compared with type I cows. However, none of these differences were statistically significant at the 95% confidence level. Significantly lower conception at first service [odds ratio (OR)=0.55, 95% confidence interval (95% CI): 0.33, 0.89] and increased number of days open (mean=24d, 95% CI: 5.2, 43) were observed in type III cows compared with type I cows. In relation to hoof health, a significantly increased risk of DD during the first lactation was found in type II and III cows (OR=5.16, 95% CI: 3.23, 8.29; and OR=12.5, 95% CI: 7.52, 21.1, respectively), as well as earlier occurrence of DD following calving (OR=59d, 95% CI=20, 96, and OR=74d, 95% CI: 37, 109). Compared with type I cows, statistically significant milk production losses during the initial 305 DIM of 199 and 335kg were estimated in type II and III cows, respectively. This difference was due to a greater rate of production decline (less persistence) after peak yield. No differences in monthly fat and protein percentages or somatic cell counts were observed between the heifer types. Given the long-term effects of DD on health, reproduction, and production, one of the priorities during the rearing period of dairy heifers should be efficient DD prevention and control programs. Such intensive intervention programs based on active long-term DD surveillance, mitigation of risk factors, and prompt treatment are expected to increase overall animal well-being and farm profitability by minimizing the effect of DD during the first lactation.

Altered microbiomes in bovine digital dermatitis lesions, and the gut as a pathogen reservoir

Bovine digital dermatitis (DD) is the most important infectious disease associated with lameness in cattle worldwide. Since the disease was first described in 1974, a series of Treponema species concurrent with other microbes have been identified in DD lesions, suggesting a polymicrobial etiology. However, the pathogenesis of DD and the source of the causative microbes remain unclear. Here we characterized the microbiomes of healthy skin and skin lesions in dairy cows affected with different stages of DD and investigated the gut microbiome as a potential reservoir for microbes associated with this disease. Discriminant analysis revealed that the microbiomes of healthy skin, active DD lesions (ulcerative and chronic ulcerative) and inactive DD lesions (healing and chronic proliferative) are completely distinct. Treponema denticola, Treponema maltophilum, Treponema medium, Treponema putidum, Treponema phagedenis and Treponema paraluiscuniculi were all found to be present in greater relative abundance in active DD lesions when compared with healthy skin and inactive DD lesions, and these same Treponema species were nearly ubiquitously present in rumen and fecal microbiomes. The relative abundance of Candidatus Amoebophilus asiaticus, a bacterium not previously reported in DD lesions, was increased in both active and inactive lesions when compared with healthy skin. In conclusion, our data support the concept that DD is a polymicrobial disease, with active DD lesions having a markedly distinct microbiome dominated by T. denticola, T. maltophilum, T. medium, T. putidum, T. phagedenis and T. paraluiscuniculi. Furthermore, these Treponema species are nearly ubiquitously found in rumen and fecal microbiomes, suggesting that the gut is an important reservoir of microbes involved in DD pathogenesis. Additionally, the bacterium Candidatus Amoebophilus asiaticus was highly abundant in active and inactive DD lesions.

High-level association of bovine digital dermatitis Treponema spp. with contagious ovine digital dermatitis lesions and presence of Fusobacterium necrophorum and Dichelobacter nodosus

Contagious ovine digital dermatitis (CODD) is an important foot disease in sheep, with significant animal welfare and economic implications. It is thought that CODD emerged from bovine digital dermatitis (BDD) via treponemal bacteria. With wildlife species such as elk now suffering a CODD-like disease, it is imperative to clarify these disease etiologies. A large investigation into treponemal association with CODD is warranted. CODD lesions (n = 58) and healthy sheep foot tissues (n = 56) were analyzed by PCR for the three BDD-associated Treponema phylogroups and two other lameness-associated bacteria, Dichelobacter nodosus and Fusobacterium necrophorum. Spirochete culture was also attempted on CODD lesions. "Treponema medium/Treponema vincentii-like," "Treponema phagedenis-like," and Treponema pedis spirochetes were identified in 39/58 (67%), 49/58 (85%), and 41/58 (71%) of CODD lesions, respectively. One or more BDD-associated Treponema phylogroups were detected in 100% of CODD lesions. Healthy foot tissues did not amplify BDD-associated Treponema phylogroup DNA. D. nodosus and F. necrophorum were present in 34/58 (59%) and 41/58 (71%) of CODD lesions and 22/56 (39%) and 5/56 (9%) of healthy foot tissues, respectively. Thirty-two spirochetes were isolated from CODD lesions, with representatives clustering with, and indistinguishable from, each of the three BDD-associated Treponema phylogroups based on 16S rRNA gene comparisons. This study for the first time demonstrates a high-level association for BDD treponeme phylogroups in CODD and their absence from healthy tissues, supporting the hypothesis that BDD treponemes play a primary causative role in CODD and confirming that the specific PCR assays are an effective differential diagnostic tool for CODD.

Oxidative stress and imbalance of mineral metabolism contribute to lameness in dairy cows

The objective of this study was to investigate correlations between oxidative stress, metabolism of mineral elements, and lameness in dairy cows. Forty multiparous Chinese Holstein dairy cows were selected and divided into two groups (healthy vs lame, n = 20) by gait score. The experiment lasted for 60 days and samples of hair, blood, and hoof were collected at days 0, 30, and 60 of experiment period, individually. Compared with healthy cows, elevation of MDA, CTX-II, COMP levels, and GSSG/GSH ratio together with depletion of SOD and MT levels in the serum were revealed in lame cows. Simultaneously, significant decreased contents of Zn, Cu, and Mn in the serum, hair, and hoof samples were shown in lame cows, but there was no obvious difference in contents of P, Mg, and Ca (except hoof Ca) in the serum, hair, and hoof between healthy and lame cows. In addition, histological examination and the hardness test demonstrated a poor hoof quality in lame cows. In summary, oxidative stress is implicated in the pathogenesis of lameness caused by imbalance of nutrients (especially selective minerals promoting healthy hoof growth) in dairy cows.

From biological models to economic optimization

This article addresses the additional challenges being faced when biological models are used as a basis for decision support in livestock herds. The challenges include dealing with uncertain information, observation costs, herd dynamics and methodological issues in relation to the computational methods applied particularly in the dynamic case. The desired key property of information included in models is that it can be used as the basis for unbiased prediction of the future performance of the animals. Often there will be a tradeoff between uncertainty and costs in the sense that the level of uncertainty can be reduced (for instance through additional tests) at some cost. Thus, the decision about which (and how many) tests to perform can be seen as an optimization problem in itself. Another way of expressing the tradeoff is to talk about the value of information which can sometimes be assessed by modeling different approaches and levels of detail in data collection. Various optimization methods of relevance to herd health management are discussed with the main emphasis on decision graphs in the static case and Markov decision processes (dynamic programming) in a dynamic context.

Short communication: Changes in gait symmetry in healthy and lame dairy cows based on 3-dimensional ground reaction force curves following claw trimming

Lameness is a frequent health problem in dairy cows. This preliminary study aimed to detect gait differences between healthy and lame walking cows using 3-dimensional force plates. We examined left-right leg symmetry changes of healthy and lame Holstein dairy cows following claw trimming. Gait scoring (GS) was performed on d -5, 0, 1, and 7 relative to claw trimming. Before the experiment, 5 cows walked normally (initial GS=1) and 4 cows limped moderately on a hind leg (initial GS=3). Gait was measured on d -2, -1, 0, 1, and 7 relative to trimming by obtaining ground reaction forces as cows walked repeatedly across 2 parallel 3-dimensional force plates. From the ground reaction forces, stance phase data were derived using computerized procedures. Left-right leg symmetries of entire curves in the 3 force directions were calculated. Effects of lameness and trimming were analyzed in a mixed model, using a low lameness threshold (GS>1). One week after claw trimming, only one cow was mildly lame. In addition, the symmetries of all 3 dimensions were significantly improved shortly after trimming. Importantly, lameness significantly worsened vertical symmetry. Lame cows walked significantly more slowly than healthy cows. In conclusion, all force symmetries seemed capable of detecting gait responses to claw trimming. Although our results are based on a small number of animals, vertical leg symmetry was affected by lameness.

Progression to multi-scale models and the application to food system intervention strategies

The aim of this article is to discuss how the systems science approach can be used to optimize intervention strategies in food animal systems. It advocates the idea that the challenges of maintaining a safe food supply are best addressed by integrating modeling and mathematics with biological studies critical to formulation of public policy to address these challenges. Much information on the biology and epidemiology of food animal systems has been characterized through single-discipline methods, but until now this information has not been thoroughly utilized in a fully integrated manner. The examples are drawn from our current research. The first, explained in depth, uses clinical mastitis to introduce the concept of dynamic programming to optimize management decisions in dairy cows (also introducing the curse of dimensionality problem). In the second example, a compartmental epidemic model for Johne's disease with different intervention strategies is optimized. The goal of the optimization strategy depends on whether there is a relationship between Johne's and Crohn's disease. If so, optimization is based on eradication of infection; if not, it is based on the cow's performance only (i.e., economic optimization, similar to the mastitis example). The third example focuses on food safety to introduce risk assessment using Listeria monocytogenes and Salmonella Typhimurium. The last example, practical interventions to effectively manage antibiotic resistance in beef and dairy cattle systems, introduces meta-population modeling that accounts for bacterial growth not only in the host (cow), but also in the cow's feed, drinking water and the housing environment. Each example stresses the need to progress toward multi-scale modeling. The article ends with examples of multi-scale systems, from food supply systems to Johne's disease. Reducing the consequences of foodborne illnesses (i.e., minimizing disease occurrence and associated costs) can only occur through an understanding of the system as a whole, including all its complexities. Thus the goal of future research should be to merge disciplines such as molecular biology, applied mathematics and social sciences to gain a better understanding of complex systems such as the food supply chain.

Association of abnormal hind-limb postures and back arch with gait abnormality in dairy cattle

Detection of lameness in individual cows is important for the prompt treatment of this painful and production-limiting disease. Current methods for lameness detection involve watching cows walk for several strides. If clinical signs predictive of lameness could be observed more conveniently, as cows are undergoing regularly scheduled examinations while standing, detection levels could increase. The objective of this study was to assess the association between postures observed while cows are standing in stanchions and clinical lameness evaluated by locomotion scoring, and to evaluate the observation of these postures as a test for lameness. The study included 1,243 cows from 4 farms. Cows were observed while standing in stanchions for regularly scheduled management procedures and the presence of arched back and cow-hocked, wide-stance, and favored-limb postures were recorded. The same cows were locomotion-scored as they exited the milking parlor. The proportion of cows observed with arched back and cow-hocked and favored-limb postures increased with increasing severity of lameness (higher locomotion score) but did not increase for the wide-stance posture. For the presence of these postures as a test for lameness (locomotion score ≥3), sensitivity and specificity were 0.63 and 0.64 for back arch, 0.54 and 0.57 for cow hocks, and 0.05 and 0.98 for favored limb. Back-arched, cow-hocked, and favored limb postures were associated with lameness but were not highly sensitive or specific as diagnostic tests. However, observation of back arch may be useful to identify cows needing further examination.

Multiresidue screening of milk withheld for sale at dairy farms in central New York State

Many of the drugs commonly used in lactating dairy cows result in residues in the milk, prohibiting its sale for human consumption. Milk withheld for sale because of drug treatment or from cows with high somatic cell counts is commonly called "waste milk." One-third of dairy farms in the United States use waste milk to feed preweaned dairy calves. Limited information is currently available on the effect of this practice on the selection and dissemination of antibiotic-resistant bacteria. Pooled waste milk samples were collected from 34 dairy farms in central New York State with the objective of detecting the presence and quantity of drug residues in these samples. Samples were collected and refrigerated using ice packs and then stored at 4°C upon arrival at the Cornell laboratory (Ithaca, NY). Screening for β-lactam, tetracycline, and sulfonamide residues in the milk was performed using commercial enzyme-linked receptor-binding assay (SNAP) tests (Idexx Laboratories Inc., Westbrook, ME). Samples with a positive SNAP test were selected for screening using a multiresidue liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The SNAP tests revealed that 75, 14.3, and 7.1% of waste milk samples (n=34) contained β-lactam, tetracycline, and sulfamethazine residues, respectively. Of the samples sent for LC-MS/MS (n=28), half had detectable quantities of drug residues. The most prevalent drugs detected by LC-MS/MS were ceftiofur (39.2%; mean ± SE concentration=0.151 ± 0.042 μg/mL), penicillin G (14.2%; mean ± SE concentration=0.008 ± 0.001 µg/mL), and ampicillin (7.1%; mean ± SE concentration=0.472 ± 0.43 µg/mL). In addition, one sample had detectable concentrations of oxytetracycline and one sample had detectable concentrations of sulfadimethoxine. These results provide insight on drug residues present in waste milk from select farm in upstate New York, and additionally indicate the need for additional studies targeting on-farm treatments that could degrade drug residues present in waste milk and reduce the potential effects on the biosphere from the disposal and use of waste milk as a feed source.

Biochemical and molecular characterization of Treponema phagedenis-like spirochetes isolated from a bovine digital dermatitis lesion

Background

Bovine papillomatous digital dermatitis (DD) is the leading cause of lameness in dairy cattle and represents a serious welfare and economic burden. Found primarily in high production dairy cattle worldwide, DD is characterized by the development of an often painful red, raw ulcerative or papillomatous lesion frequently located near the interdigital cleft and above the bulbs of the heel. While the exact etiology is unknown, several spirochete species have been isolated from lesion material. Four isolates of Treponema phagedenis-like spirochetes were isolated from dairy cows in Iowa. Given the distinct differences in host, environmental niche, and disease association, a closer analysis of phenotypic characteristics, growth characteristics, and genomic sequences of T. phagedenis, a human genitalia commensal, and the Iowa DD isolates was undertaken.

Results

Phenotypically, these isolates range from 8.0 to 9.7 μm in length with 6–8 flagella on each end. These isolates, like T. phagedenis, are strictly anaerobic, require serum and volatile fatty acids for growth, and are capable of fermenting fructose, mannitol, pectin, mannose, ribose, maltose, and glucose. Major glucose fermentation products produced are formate, acetate, and butyrate. Further study was conducted with a single isolate, 4A, showing an optimal growth pH of 7.0 (range of 6–8.5) and an optimal growth temperature of 40°C (range of 29°C-43°C). Comparison of partial genomic contigs of isolate 4A and contigs of T. phagedenis F0421 revealed > 95% amino acid sequence identity with amino acid sequence of 4A. In silico DNA-DNA whole genome hybridization and BLAT analysis indicated a DDH estimate of >80% between isolate 4A and T. phagedenis F0421, and estimates of 52.5% or less when compared to the fully sequenced genomes of other treponeme species.

Conclusion

Using both physiological, biochemical and genomic analysis, there is a lack of evidence for difference between T. phagedenis and isolate 4A. The description of Treponema phagedenis should be expanded from human genital skin commensal to include being an inhabitant within DD lesions in cattle.

Comparison of modeled sampling strategies for estimation of dairy herd lameness prevalence and cow-level variables associated with lameness

Monitoring herd lameness prevalence has utility for dairy producers and veterinarians in their efforts to reduce lameness, for animal welfare assessment programs, and for researchers. Locomotion scoring is a method used to quantify lameness and calculate prevalence. Because of the time necessary to locomotion score each cow in large dairy herds, a sampling strategy to determine herd lameness prevalence that allows scoring of fewer cows would be useful. Such a sampling strategy must be validated for accuracy compared with the lameness prevalence when all cows in a herd are locomotion scored. The purpose of this study was to assess 3 previously suggested methods of estimating lameness prevalence by strategic sampling of dairy herds. Sampling strategies tested included (1) sampling a calculated number of cows in the middle third of the milking parlor exit order for each pen, (2) sampling a calculated number of cows weighted across pens and distributed evenly within each pen, and (3) sampling all cows in the high production, low production, and hospital pens. Lactating cows on 5 dairy farms in Washington and Oregon (n=4,422) were locomotion scored using a 5-point scale to determine herd-level lameness prevalence (percentage with locomotion score ≥3). Milking parlor exit order, order in headlocks at the feed bunk within each pen, and breed were recorded for each cow. The number of days in lactation, milk production, and parity were collected from farm computer records. Pen grouping strategy for each farm was obtained by interview with farm management. Sampling strategies were modeled using the locomotion score data set for each herd. Estimates of lameness prevalence obtained from the milking parlor exit order sample and the sample distributed across pens were within 5 percentage points of the whole herd prevalence. The third strategy estimated the lameness prevalence within 5 percentage points on 4 farms, but overestimated prevalence on 1 farm. Pen-level prevalence obtained by locomotion score of all cows in the pen was variable and not reliably predictive of herd-level prevalence. Cows of Holstein breed, parity >1, and exiting the milking parlor in the last 20% of the pen had greater odds of lameness compared with other breeds, parities, and milking parlor exit order groups in a multivariate analysis. This study indicates that the sampling strategies using the middle of milking parlor exit order and a calculated sample distributed across the herd may be used to obtain an estimate of herd lameness prevalence.

Lameness detection based on multivariate continuous sensing of milk yield, rumination, and neck activity

The objective of this study was to develop and validate a mathematical model to detect clinical lameness based on existing sensor data that relate to the behavior and performance of cows in a commercial dairy farm. Identification of lame (44) and not lame (74) cows in the database was done based on the farm's daily herd health reports. All cows were equipped with a behavior sensor that measured neck activity and ruminating time. The cow's performance was measured with a milk yield meter in the milking parlor. In total, 38 model input variables were constructed from the sensor data comprising absolute values, relative values, daily standard deviations, slope coefficients, daytime and nighttime periods, variables related to individual temperament, and milk session-related variables. A lame group, cows recognized and treated for lameness, to not lame group comparison of daily data was done. Correlations between the dichotomous output variable (lame or not lame) and the model input variables were made. The highest correlation coefficient was obtained for the milk yield variable (rMY=0.45). In addition, a logistic regression model was developed based on the 7 highest correlated model input variables (the daily milk yield 4d before diagnosis; the slope coefficient of the daily milk yield 4d before diagnosis; the nighttime to daytime neck activity ratio 6d before diagnosis; the milk yield week difference ratio 4d before diagnosis; the milk yield week difference 4d before diagnosis; the neck activity level during the daytime 7d before diagnosis; the ruminating time during nighttime 6d before diagnosis). After a 10-fold cross-validation, the model obtained a sensitivity of 0.89 and a specificity of 0.85, with a correct classification rate of 0.86 when based on the averaged 10-fold model coefficients. This study demonstrates that existing farm data initially used for other purposes, such as heat detection, can be exploited for the automated detection of clinically lame animals on a daily basis as well.

Effects of rubber flooring during the first 2 lactations on production, locomotion, hoof health, immune functions, and stress

Some housing systems on dairy farms can result in long-term chronic pain. The effects of acute pain on immunity have been explored, but chronic pain's influence on immune responses is still poorly understood. Therefore, the objective of this research was to determine chronic effects of flooring on immune responses and production in freestall housing for dairy cows. Thirty heifers were studied from before calving as first-calf heifers until d 180 of their second lactation. Treatments were rubber (Kraiburg; Agromatic Inc., Fond du Lac, WI) flooring or concrete with diamond grooves in a freestall barn, each in 2 quadrants of the barn. Heifers entered the treatments after calving, so the system was dynamic and each cow was considered an experimental unit. At the end of the first lactation, cows were housed in a bedded pack barn with pasture access until calving was imminent. At that time, they returned to their assigned treatment, but not necessarily into the same quadrant. Production, reproduction, cortisol, acute-phase proteins, and health data were recorded throughout lactation 1, locomotion was scored weekly, and hoof scoring and care was conducted on d 60 and 180 of lactations 1 and 2, and quantitative real-time-PCR of blood leukocytes was analyzed in mid lactation of lactation 1. Mature-equivalent milk fat, milk protein, and protein percentages during the first lactation were greater for cows on the rubber flooring. Hoof and leg therapy treatments per cow were fewer for rubber floor-housed cows. Locomotion scores were less for cows housed on rubber during the second lactation. White blood cell counts were less for cows housed on rubber, and caused by greater lymphocyte counts for cows housed on concrete. The possibility of chronic inflammation was substantiated by less IL-1β and more IL-1 receptor antagonists for cows housed on rubber at d 150 in the second lactation. Cortisol and acute-phase proteins did not differ between the treatments. Interferon-γ, IL-12, the modulator of tissue reconstruction (B-cell-transforming growth factor 1), and pain-modulating neurokinin (tachykinin 1) were not different at d 105. These data show indicators of chronic inflammation for cows housed on the concrete flooring compared with those housed on rubber. Implications for the use of rubber flooring in freestall barns are broader than just lameness and may affect many aspects of cow physiology and production.