Symposium review: Real-time continuous decision making using big data on dairy farms.

We are developing a real-time, data-integrated, data-driven, continuous decision-making engine, The Dairy Brain, by applying precision farming, big data analytics, and the Internet of Things. This is a transdisciplinary research and extension project that engages multidisciplinary scientists, dairy farmers, and industry professionals. Dairy farms have embraced large and diverse technological innovations such as sensors and robotic systems, and procured vast amounts of constant data streams, but they have not been able to integrate all this information effectively to improve whole-farm decision making. Consequently, the effects of all this new smart dairy farming are not being fully realized. It is imperative to develop a system that can collect, integrate, manage, and analyze on- and off-farm data in real time for practical and relevant actions. We are using the state-of-the-art database management system from the University of Wisconsin-Madison Center for High Throughput Computing to develop our Agricultural Data Hub that connects and analyzes cow and herd data on a permanent basis. This involves cleaning and normalizing the data as well as allowing data retrieval on demand. We illustrate our Dairy Brain concept with 3 practical applications: (1) nutritional grouping that provides a more accurate diet to lactating cows by automatically allocating cows to pens according to their nutritional requirements aggregating and analyzing data streams from management, feed, Dairy Herd Improvement (DHI), and milking parlor records; (2) early risk detection of clinical mastitis (CM) that identifies first-lactation cows under risk of developing CM by analyzing integrated data from genetic, management, and DHI records; and (3) predicting CM onset that recognizes cows at higher risk of contracting CM, by continuously integrating and analyzing data from management and the milking parlor. We demonstrate with these applications that it is possible to develop integrated continuous decision-support tools that could potentially reduce diet costs by $99/cow per yr and that it is possible to provide a new dimension for monitoring health events by identifying cows at higher risk of CM and by detecting 90% of CM cases a few milkings before disease onset. We are securely advancing toward our overarching goal of developing our Dairy Brain. This is an ongoing innovative project that is anticipated to transform how dairy farms operate.

Health parameters and their association with price in young calves sold at auction for veal operations in Québec, Canada.

The veal calf industry in Québec depends on young calves' availability at auction. Most of these calves come from dairy farms. The aim of this cross-sectional study was to determine the effect of clinical anomalies and other calf characteristics on their sale price. A total of 3,820 calves from 5 different auctions were included in this observational study. The calves were examined by a veterinarian on arrival at the auction and screened for umbilical anomalies, the presence of nasal or eye discharge, joint abnormality, diarrhea, appearance of neonatal characteristics (compatible with age less than 1 wk), and general health status mainly based on the presence of depression and dehydration. The final multivariable model included 5 different variables (calf weight, sex, breed, abnormal joints, and general health status) and the interaction between sex and general health status. The presence of abnormal joints and unhealthy characteristics was negatively associated with standardized price. Female calves and mixed breed beef calves were positively associated with standardized price. Finally, the calves' weight was associated with standardized price in a quadratic fashion. Ongoing or previous diarrhea had no effects on standardized price. This study will be helpful for both dairy and veal producers for improving the quality of calves sold to the Québec auction market.

Use of a stochastic simulation model to estimate the cost per case of digital dermatitis, sole ulcer, and white line disease by parity group and incidence timing.

A farm-level stochastic simulation model was modified to estimate the cost per case of 3 foot disorders (digital dermatitis, sole ulcer, and white line disease) by parity group and incidence timing. Disorder expenditures considered within the model included therapeutics, outside labor, and on-farm labor. Disorder losses considered within the model included discarded milk, reduced milk production, extended days open, an increased risk of culling, an increased risk of death (natural or euthanized), and disease recurrence. All estimates of expenditures and losses were defined using data from previously published research in stochastic distributions. Stochastic simulation was used to account for variation within the farm model; 1,000 iterations were run. Sensitivity of foot disorder costs to selected market prices (milk price, feed price, replacement heifer price, and slaughter price) and herd-specific performance variables (pregnancy rate) were analyzed. Using our model assumptions, the cost per disorder case over all combinations of parity group and incidence timing, regardless of incidence likelihood, was lowest for digital dermatitis ($64 ± 24; mean ± standard deviation), followed by white line disease ($152 ± 26) and sole ulcer ($178 ± 29). Disorder costs were greater in multiparous versus primiparous cows and were always highest at the beginning of lactation. The greatest contributing cost categories were decreased milk production, an increased risk of culling, and disease recurrence. The contribution of cost categories to the total cost of disorder varied by disorder type, parity group, and incidence timing. For all disorders, the cost per case increased as milk price or replacement heifer price increased and decreased as feed price, pregnancy rate, or slaughter price increased. Understanding how foot disorder costs change according to cow-specific conditions (i.e., disorder type, parity group, and days in milk at incidence) and herd-specific conditions (i.e., market prices and performance variables) can help improve on-farm decisions about treatment and prevention of foot disorders.

Objective assessment of lameness in cattle after foot surgery.

Assessment of lameness in cattle after foot surgery is important to monitor the recovery period, to improve the long-term success and the cows` welfare. This longitudinal multicenter retrospective study was carried out to evaluate the usefulness of automated tools of weight bearing and gait analysis following foot surgery to support the clinician to monitor lameness in cattle. For this purpose, the effect of involvement of different anatomical structures and the use of different surgery methods on gait parameters of post-operative recovery was assessed. The study consisted of 2 experiments and included cattle with unilateral foot pathologies located in the digital region which needed 1 (experiment 1; n = 30) or 2 (experiment 2; n = 4) surgical interventions. The surgical techniques were debridement, joint lavage, partial resection of bones, tendons or synovial structures, total resection of the sesamoid bone and digit amputation. Two accelerometers (400 Hz; kinematic outcome = stance phase duration; kinetic outcome = foot load and toe-off), a 4-scale weighing platform (difference of mean weight distribution across the limbs; Δweight) and a subjective locomotion score were used to evaluate gait parameters every 3 to 4 days after surgery. A repeated measures ANOVA was used in experiment 1 and a receiver operator characteristic analysis was used to determine the optimal cutoff values in experiment 2. Results showed that the differences across limbs for the pedogram variables of stance phases and peaks of foot load and toe-off, Δweight and the locomotion score were highest if joints or sesamoid bones were involved, suggesting that these cattle were more severely lame compared to cattle with more superficial foot pathologies. There was a significantly lower degree of lameness after surgical debridement and after digit amputation compared to partial and total resection of anatomical structures of the foot. The use of accelerometers and a 4-scale weighing platform represent promising objective tools for post-operative monitoring of lameness and can support the clinician in gait assessment to improve the long-term success of surgical interventions in the area of the foot.

A review and quantitative assessment of cattle-related thermal indices.

Many thermal indices have been developed to assess the levels of heat stress imposed on cattle during hot weather. In this paper, the 16 cattle-related thermal indices are critically reviewed. The primary emphasis is to evaluate each index's coherence to the typical heat transfer characteristics of a cow. Other perspectives including incorporated environmental parameters in the equation(s), experimental data, correlated physiological responses, heat-stress thresholds, scope of application, specific cattle breed involved, and experiment location(s) are also well categorised and discussed. The coherence evaluation indicates that the main effects of environmental parameters on heat stress have been properly reflected, while some interactions between the parameters have been treated differently. Given the variety of the equations used to define the 16 indices and the wide range of information used to develop each index, we conclude that each thermal index is distinct to an extent that it should be selected and employed carefully.

Behavioral changes in group-housed dairy calves infected with Mannheimia haemolytica.

Monitoring sickness behavior may improve identification, management, and welfare of sick animals. The objective of this study was to characterize components of sickness behavior in group-housed dairy calves, using an experimental disease challenge model with Mannheimia haemolytica (MH). Holstein bull calves (aged 3-7 weeks; 58.0 ± 12.0 kg of body weight) were group-housed based on age and body weight in sand-bedded pens (6 calves/pen, 6.6 m2/calf) and provided pasteurized waste milk (8 L/d) 2×/d and grain concentrate ad libitum. Within group, calves were randomly assigned to 1 of 2 treatments: (1) inoculation at the tracheal bifurcation with 3 × 109 cfu of MH suspended in 5 mL of sterile phosphate buffered saline (PBS) followed by a 120 mL wash PBS (MH; n = 12, 3/pen), or (2) inoculation with 5 mL + 120 mL of sterile PBS only (control; n = 12, 3/pen). Rectal temperature and health scores were collected from d 0 to +6 of the challenge. A range of behaviors, including feeding patterns and social interactions, were recorded from video from d 0 to +2. The challenge model resulted in calves experiencing a mild disease state: rectal temperatures of MH calves were elevated throughout the challenge compared with control calves, peaking at 12 h postinoculation (39.2 vs. 38.9°C; standard error = 0.14). Many behavioral responses were subject to treatment by day effects, with calves generally becoming less active following inoculation with MH and then returning to baseline. Affected behaviors surrounding feeding included milk feeding time, frequency of competitive displacements, and concentrate feeding time. Lying time was similarly subject to treatment by day effects, and MH calves also spent more time lying on their left side compared with their right (604 vs. 471 min/h; standard error = 32), whereas control calves expressed no laterality. Duration of social lying did not differ, but frequency of social lying bouts decreased in MH calves following inoculation (0.44 vs. 0.75 bouts/h; standard error = 0.04). Social grooming was initiated less by MH calves (0.78 vs. 1.96 min/h; standard error = 0.38), but they tended to receive more social grooming for a greater duration of time (1.59 vs. 1.25 min/h; standard error = 0.13). Overall, we found that infected calves exhibited reduced grooming, feeding, and social interactions, suggesting that these behavioral changes may be useful indicators of early stages of respiratory disease.

Assessment of heat stress in 7-week old dairy calves with non-invasive physiological parameters in different thermal environments.

We estimated thermal stress in 7-week old Holstein bull calves during a warm episode in summer to study acute physiological responses of calves to heat stress. Data were collected over a 5-day period: day 1 (control), day 2 (heat stress), and a 3-day post-stress period in shaded (n = 8) and unshaded (n = 8) thermal environments. On the control day, both groups were shaded. Thermal environment was characterized by relative humidity, ambient temperature, and the temperature-humidity index (THI). Physiological variables included respiratory rate, rectal temperature, ear skin temperature and heart rate. Correlations between animal-based and meteorological indices were calculated, and ambient temperature correlated slightly better with physiological measures than THI. Rectal temperature was the only animal-based parameter that showed stronger correlations with the thermal indices when calculated for the shaded than for the unshaded environment [r = 0.42 vs. r = 0.47, P = 0.032 (ambient temperature), r = -0.39 vs. r = -0.45, P = 0.012 P = 0.015 (relative humidity), r = 0.41 vs. r = 0.46, P = 0.022 (THI)]. No differences were found between groups during the control day for any of the physiological parameters. During days 2 and 3, average and maximal values of respiratory and heart rates were higher in unshaded calves than in shaded ones. Maximal respiratory rates were in average by 25.9, 17.8 and 10.1 breaths/min lower in shaded calves than in unshaded calves for days 2, 3 and 4, respectively (P < 0.001, P < 0.001 and P = 0.024). Maximal heart rate was 127.4 ± 8.5 vs. 99.2 ± 6.3 beats/min on the heat stress day (P < 0.001), and 121.0 ± 6.9 vs. 103.4 ± 7.7 beats/min on day 3 (P = 0.006) in unshaded and shaded calves, respectively. Maximal body temperatures were higher measured either in the rectum or on the ear skin in unshaded calves than in shaded ones (with 0.5 and 1.6°C, P = 0.040 and P = 0.018, respectively), but only on the heat stress day. Based on our results, shading of young calves may be adequate for alleviating acute heat stress in continental regions. Ambient temperature is appropriate to estimate acute heat stress in dairy calves.

Economic Significance of Tropical Theileriosis on a Holstein Friesian Dairy Farm in Pakistan.

The dairy industry in Pakistan is booming, and investors are anxious to fund dairy farms that are using high-milk-producing (exotic) cattle breeds such as Holstein Friesians that are not native to the country. Unfortunately, the benefits of increased milk production do not provide resistance to pathogens present in regions where the exotic breeds are introduced. Therefore, the current study was conducted to evaluate the economic impact of Theileria annulata on a commercial Holstein Friesian dairy farm in the District of Ranjanpur, in the Province of Punjab, Pakistan. The economic impact of T. annulata infection was calculated for cattle with subclinical and clinical theileriosis. Losses were estimated based on milk production, morbidity, mortality, and tick control costs (organophosphate sprays). Animals were classified into groups after screening for mastitis, teat abnormality, abnormal parturition, intestinal parasites, and hemoparasites ( T. annulata, Babesia spp., and Anaplasma spp.). Microscopy was done for hemoparasites and intestinal parasites. PCR was used to confirm microscopic identification of T. annulata. Animals were classified into 3 groups: group A (normal), group B (subclinical theileriosis), and group C (acute theileriosis). Hemoparasites were observed microscopically in 28.7% of cows. Theileria annulata was found in 8%, and the herd incidence (new cases) of T. annulata was 2.8%. Milk production, animal rectal temperature, and body condition scores between group A and groups B and C were significantly different ( P < 0.05). But the enlargement of sub-scapular lymph node and interval of body condition score of the 3 groups were not significant ( P > 0.05). The total expenditure incurred due to theileriosis was US $74.98 per animal and 13.83% of total farm costs. Hence theileriosis caused significant economic loss of US $18,743.76 (0.02 million) on this Holstein Friesian dairy.

Economic costs of recorded reasons for cow mortality and culling in a pasture-based dairy industry.

The objective of this study was to determine the economic costs associated with different reasons for cow culling or on-farm mortality in a pasture-based seasonal system. A bioeconomic model was developed to quantify costs associated with the different farmer-recorded reasons and timing of cow wastage. The model accounted for the parity and stage of lactation at which the cows were removed as well as the consequent effect on the replacement rate and average age structure of the herd. The costs and benefits associated with the change were quantified, including animal replacement cost, cull salvage value, milk production loss, and the profitability of altered genetic merit based on industry genetic trends for each parity. The total cost of cow wastage was estimated to be NZ$23,628/100 cows per year (NZ$1 = US$0.69) in a pasture-based system. Of this total cost, NZ$14,300/100 cows worth of removals were for nonpregnancy and unknown reasons, and another NZ$3,631/100 cows was attributed to low milk production, mastitis, and udder problems. The total cost for cow removals due to farmer-recorded biological reasons (excluding unknown, production, and management-related causes) was estimated to be NZ$13,632/100 cows per year. Of this cost, an estimated NZ$10,286/100 cows was attributed to nonpregnancy, mastitis, udder problems, calving trouble, and injury or accident. There is a strong economic case for the pasture-based dairy industries to invest in genetic, herd health, and production management research focused on reducing animal wastage due to reproductive failure, mastitis, udder problems, injuries or accidents, and calving difficulties.

Mobility Scoring of Finished Cattle.

Lameness is among the most important welfare and production issues affecting dairy cattle. Recently, it has received significant research emphasis. Certain events in 2013 within the cattle industry heightened the focus on mobility issues in finished cattle. Scoring systems are needed in the finished cattle industry to capture and measure mobility issues at packing facilities. The North American Meat Institute Animal Welfare Committee helped facilitate the creation of a scoring system to evaluate mobility of cattle at packing plants, providing the cattle industry with a tool to benchmark and improve the welfare of finished cattle.

Towards practical application of sensors for monitoring animal health: the effect of post-calving health problems on rumination duration, activity and milk yield.

Three sources of sensory data: cow's individual rumination duration, activity and milk yield were evaluated as possible indicators for clinical diagnosis, focusing on post-calving health problems such as ketosis and metritis. Data were collected from a computerised dairy-management system on a commercial dairy farm with Israeli Holstein cows. In the analysis, 300 healthy and 403 sick multiparous cows were studied during the first 3 weeks after calving. A mixed model with repeated measurements was used to compare healthy cows with sick cows. In the period from 5 d before diagnosis and treatment to 2 d after it, rumination duration and activity were lower in the sick cows compared to healthy cows. The milk yield of sick cows was lower than that of the healthy cows during a period lasting from 5 d before until 5 d after the day of diagnosis and treatment. Differences in the milk yield of sick cows compared with healthy cows became greater from 5 to 1 d before diagnosis and treatment. The greatest significant differences occurred 3 d before diagnosis for rumination duration and 1 d before diagnosis for activity and milk yield. These results indicate that a model can be developed to automatically detect post-calving health problems including ketosis and metritis, based on rumination duration, activity and milk yield.

The effect of paratuberculosis on milk yield--A systematic review and meta-analysis.

Bovine paratuberculosis is a disease characterized by chronic granulomatous enteritis causing protein-losing enteropathy. Adverse effects on animal productivity are key drivers in the attempt to control paratuberculosis at the farm level. Economic models require an accurate estimation of the production effects associated with paratuberculosis. The aim of this study was to conduct a systematic review and meta-analysis to investigate the effect of paratuberculosis on milk production. A total of 20 effect estimates from 15 studies were included in the final meta-analysis. Substantial between-study heterogeneity was observed. Subgroup analysis by case definition and study design was carried out to investigate heterogeneity. The majority of between-study variation was attributed to studies that defined cases on serology. Calculation of a pooled effect estimate was only appropriate for studies that defined cases by organism detection. A reduction in milk yield, corrected for lactation number and herd of origin of 1.87 kg/d, equivalent to 5.9% of yield, was associated with fecal culture or PCR positivity in individual cows.

Short communication: Ultrasonographic assessment of lung consolidation postweaning and survival to the first lactation in dairy heifers.

The aim of this prospective cohort study was to assess the association of systematic thoracic ultrasonography findings postweaning on calves' survivability to the first lactation. Three-month-old Jersey heifers (n=250) returning from a custom heifer grower were scanned by thoracic ultrasonography and lungs assessed using a scoring system with a scale from 1 to 4. A score of 1 was attributed to calves with no abnormality. A score of 2 was assigned if multiple comet tails or B-lines (coalescence of multiple comet tails) were observed. A score of 3 was assigned to calves with ≥1 location of lung consolidation ≥1 cm but <6 cm. Calves with extensive consolidation (≥6 cm in one or more locations) or evidence of abscessation or pleural effusion (>1 cm) were assigned a score of 4. Calves with a score of 4 had greater risk of dying or being culled [26% (95% credibility interval: 13-47%)] than calves with a score of 1 [1% (0-6%)], 2 [3% (1-9%)], or 3 [5% (1-17%)]. We found no association between age of first calving in the remaining calves and lung score. Thus, lung lesion severity assessed by thoracic ultrasound is associated with a long-term production outcome.

Reduction in daily milk yield associated with subclinical bovine herpesvirus 1 infection.

The aim of this observational cohort study was to investigate the potential economic impact of subclinical bovine herpesvirus 1 (BoHV-1) infection in a commercial UK dairy herd in terms of milk yield depression. Infection status of cows (infected or not infected) was assigned from serology on a single occasion. A multi-level linear model was used to evaluate the impact of infection status on milk production, using milk records that were routinely collected over two years. BoHV-1 seropositive cows produced 2.6 kg/day less milk over the study period compared with cows that were seronegative. This result highlights the importance of appropriate management of risks associated with subclinical infection with BoHV-1 as part of proactive herd health and production management.

Assessment of the excretion time of electronic capsules placed in the intestinal lumen of cows with cecal dilatation-dislocation, healthy control cows, and cows with left displacement of the abomasum.

OBJECTIVE: To analyze the transit time from various locations in the intestines of cows with cecal dilatation-dislocation (CDD), healthy control cows, and cows with left displacement of the abomasum (LDA). ANIMALS: 15 cows with naturally occurring CDD (group 1), 14 healthy control cows (group 2), and 18 cows with LDA (group 3). PROCEDURES: 5 electronic transmitters were encased in capsules and placed in the lumen of the ileum, cecum, proximal portion of the colon, and 2 locations in the spiral colon (colon 1 and colon 2) and used to measure the transit time (ie, time between placement in the lumen and excretion of the capsules from the rectum). Excretion time of the capsules from each intestinal segment was compared among groups. RESULTS: Cows recovered well from surgery, except for 1 cow with relapse of CDD 4 days after surgery and 2 cows with incisional infection. High variability in capsule excretion times was observed for all examined intestinal segments in all groups. Significant differences were detected for the excretion time from the colon (greater in cows with CDD than in healthy control cows) and cecum (less in cows with LDA than in cows of the other 2 groups). CONCLUSIONS AND CLINICAL RELEVANCE: The technique developed to measure excretion time of capsules from bovine intestines was safe and reliable; however, the large variability observed for all intestinal segments and all groups would appear to be a limitation for its use in assessment of intestinal transit time of cattle in future studies.

Casein hydrolysate for uterine infection treatment: a patent evaluation (WO2011132191).

Metritis, endometritis and pyometra are common uterus inflammatory diseases, occurring mainly in the early postpartum period of livestock and farm animals. These infections are primarily associated with contamination of the reproductive tract, in particular uterine. Uterine infections bring to uterine and cervical involution as well as sub-fertility; the high economic loss, due to costs for treatment, milk withdrawal, reduced reproductive performance and premature culling, clearly demonstrate that uterine health in the postpartum period requires substantial medical veterinary attention. A wide variety of therapies for endometritis have been reported, including mainly antibiotics administered either by systemic or local somministration. Here, the patent application WO/2011/132191, which describes an alternative treatment for uterine infection, using casein peptides, is evaluated and discussed.

Measurement of acceleration while walking as an automated method for gait assessment in dairy cattle.

The aims were to determine whether measures of acceleration of the legs and back of dairy cows while they walk could help detect changes in gait or locomotion associated with lameness and differences in the walking surface. In 2 experiments, 12 or 24 multiparous dairy cows were fitted with five 3-dimensional accelerometers, 1 attached to each leg and 1 to the back, and acceleration data were collected while cows walked in a straight line on concrete (experiment 1) or on both concrete and rubber (experiment 2). Cows were video-recorded while walking to assess overall gait, asymmetry of the steps, and walking speed. In experiment 1, cows were selected to maximize the range of gait scores, whereas no clinically lame cows were enrolled in experiment 2. For each accelerometer location, overall acceleration was calculated as the magnitude of the 3-dimensional acceleration vector and the variance of overall acceleration, as well as the asymmetry of variance of acceleration within the front and rear pair of legs. In experiment 1, the asymmetry of variance of acceleration in the front and rear legs was positively correlated with overall gait and the visually assessed asymmetry of the steps (r ≥ 0.6). Walking speed was negatively correlated with the asymmetry of variance of the rear legs (r=-0.8) and positively correlated with the acceleration and the variance of acceleration of each leg and back (r ≥ 0.7). In experiment 2, cows had lower gait scores [2.3 vs. 2.6; standard error of the difference (SED)=0.1, measured on a 5-point scale] and lower scores for asymmetry of the steps (18.0 vs. 23.1; SED=2.2, measured on a continuous 100-unit scale) when they walked on rubber compared with concrete, and their walking speed increased (1.28 vs. 1.22 m/s; SED=0.02). The acceleration of the front (1.67 vs. 1.72 g; SED=0.02) and rear (1.62 vs. 1.67 g; SED=0.02) legs and the variance of acceleration of the rear legs (0.88 vs. 0.94 g; SED=0.03) were lower when cows walked on rubber compared with concrete. Despite the improvements in gait score that occurred when cows walked on rubber, the asymmetry of variance of acceleration of the front leg was higher (15.2 vs. 10.4%; SED=2.0). The difference in walking speed between concrete and rubber correlated with the difference in the mean acceleration and the difference in the variance of acceleration of the legs and back (r ≥ 0.6). Three-dimensional accelerometers seem to be a promising tool for lameness detection on farm and to study walking surfaces, especially when attached to a leg.

Assessment of Dietzia subsp. C79793-74 for treatment of cattle with evidence of paratuberculosis.

The objective of the present investigation was to determine whether the bacterium Dietzia subsp. C79793-74, previously shown to inhibit growth of Mycobacterium subsp. paratuberculosis under in vitro culture conditions, has therapeutic value as a probiotic for adult cattle with paratuberculosis.  Animals were obtained from several herds with evidence of disease based on seropositivity and/or fecal shedding.  Sixty-eight cows with initial evidence of Stage II or III paratuberculosis and 2 with an initial Stage IV disease were evaluated longitudinally.  Animals were either treated daily with variable, disease-dependent doses of Dietzia (n = 48) or left untreated (n = 22).  Clinical aspects of disease (diarrhea, emaciated, cachectic and appetite) were recorded until the animal recovered or required euthanasia due to advanced clinical paratuberculosis or other severe conditions.  Paratuberculosis parameters-antibody serology (ELISA, AGID) and fecal culture-were longitudinally monitored over the lifetime of each animal.  The results indicated that daily treatment with Dietzia was therapeutic for paratuberculosis cows based on: (a) longitudinal decline in ELISA values only occurred in animals that were treated; (b) prolonged survival was dependant upon treatment--the length being directly associated with low initial ELISA values; and (c) treated animals were the only ones cured of disease.  Further investigations are envisaged to determine optimal, long-term dosages that may result in even better therapeutic outcomes as well as to evaluate potential application for therapy of the Johne's disease, human-counterpart, Crohn's disease.

Time budgets of lactating dairy cattle in commercial freestall herds.

The aim of this study was to examine the time budgets of 205 lactating dairy cows housed in 16 freestall barns in Wisconsin and to determine the relationships between components of the time budget and herd- and cow-level fixed effects using mixed models. Using continuous video surveillance, time lying in the stall, time standing in the stall, time standing in the alleys (including drinking), time feeding, and time milking (time out of the pen for milking and transit) during a 24-h period were measured for each cow. In addition, the number of lying bouts and the mean duration of each lying bout per 24-h period were determined. Time milking varied between cows from 0.5 to 6.0 h/d, with a mean ± standard deviation of 2.7 ± 1.1h/d. Time milking was influenced significantly by pen stocking density, and time milking negatively affected time feeding, time lying, and time in the alley, but not time standing in the stall. Locomotion score, either directly or through an interaction with stall base type (a rubber crumb-filled mattress, MAT, or sand bedding, SAND), influenced pen activity. Lame cows spent less time feeding, less time in the alleys, and more time standing in the stalls in MAT herds, but not in SAND herds. The effect of lameness on lying time is complex and dependent on the time available for rest and differences in resting behavior observed between cows in MAT and SAND herds. In MAT herds, rest was characterized by a larger number of lying bouts of shorter duration than in SAND herds (mean = 14.4; confidence interval, CI: 12.4 to 16.5 vs. mean = 10.2; CI: 8.2 to 12.2 bouts per d, and mean = 1.0; CI: 0.9 to 1.1 vs. mean = 1.3, CI: 1.2 to 1.4h bout duration for MAT and SAND herds, respectively). Lameness was associated with an increase in time standing in the stall and a reduction in the mean (CI) number of lying bouts per day from 13.2 (CI: 12.3 to 14.1) bouts/d for nonlame cows to 10.9 (CI: 9.30 to 12.8) bouts/d for moderately lame cows, and an overall reduction in lying time in MAT herds compared with SAND herds (11.5; CI: 10.0 to 13.0 vs. 12.7; CI: 11.0 to 14.3h/d, respectively). These results show that time out of the pen milking, stall base type, and lameness significantly affect time budgets of cows housed in freestall facilities.

Evaluation of a milk-flow assessment technique in dairy cows with normal teat canals or stenotic teat canals.

OBJECTIVE: To assess the usefulness and reliability of a milk-flow measurement technique and the values obtained in unobstructed teats and teats with teat canal stenosis in dairy cows. ANIMALS: 16 Holstein cows. PROCEDURES: Teats were assessed via hand milking and classified as unobstructed or partially obstructed. Partially obstructed teats were further categorized according to the anatomic location of the obstruction via ultrasonography into teat canal obstruction (TCO) and obstruction at the proximal portion of the teat canal (Fürstenberg rosette obstruction [FRO]) The milk-flow characteristics of the teat canal were assessed by measuring the intracisternal pressure at the start (PSL) and at cessation (PCL) of leakage of an infused solution. RESULTS: The PSL and PCL values among unobstructed teats were not significantly different between lactating and nonlactating cows nor among quarters. In assessment of test-retest intrarater reliability, a high degree of correlation was detected for PSL (correlation coefficient, 0.94; 95% confidence interval, 0.90 to 0.96) and PCL (correlation coefficient, 0.92; 95% confidence interval, 0.86 to 0.95). Teats with TCO and FRO had higher PSL and PCL values, compared with unobstructed teats. Teats with FRO had significantly higher PSL but lower PCL than teats with TCO. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated the usefulness and reliability of the technique in assessing the milk-flow characteristics of the teat canal. The milk-flow pattern of teats with teat canal stenosis varies depending on the location of obstruction. This technique may be a valuable tool in evaluating the effectiveness of teat canal surgery.