A survey of practices and attitudes around cull cow management by bovine veterinarians in Ontario,Canada

The removal (culling) of dairy cows from the farm is a regular and required management practice. The main objectives of this study were to describe the involvement of bovine veterinarians in Ontario, Canada, in dairy cull cow management decisions, their expectations of current producer practices, and their perspectives on welfare issues and best management practices for cull dairy cows. Between February and May 2021, a province-wide survey was conducted among all members of the Ontario Association of Bovine Practitioners (OABP), with questions addressing veterinarians' background and demographics, veterinary clinic characteristics, cull cow management, down cow management, and learning preferences. The response rate for the survey was 25.1%, with 45 responses meeting all eligibility criteria. Dairy veterinarians would like to have greater involvement in cull cow management; when asked for desired involvement in culling decisions, 57.5% of veterinarians would like to be involved in culling decisions most of the time or always. Most (70.0%) veterinarians believed that cull cow welfare has improved over the last decade. However, most respondents also identified at least one area of management (farm of origin, transportation, auction, slaughter) as currently being a high risk to cull cow welfare. Given the frequency of their visits, trust by dairy producers, and knowledge, herd veterinarians are among those in the best position to improve the care of cull dairy cows. Information generated from this survey can be used to inform the development of improved decision-making tools for culling cows, and this, along with increased veterinarians' involvement in cull cow management, could improve the economic and welfare outcomes of culling decisions for dairy producers.     

Dairy nutrition management: Assessing a comprehensive continuing education program for veterinary practitioners

The purpose of this study was to assess the effectiveness of a team-based educational program designed to enhance the flow of applied, research-based, nutrition information to dairy veterinarians. A comprehensive dairy cattle nutrition curriculum was developed and participants from 11 veterinary practices located in 5 states (IN, NY, PA, NM, and OH), serving an estimated 186,150 dairy cattle in 469 herds, attended the 2 advanced nutrition modules (∼2.5 d each and ∼40 h of learning) held in 2009. Nutrients, feeding transition cows, calves, and heifers, dry matter intake, feed storage, metabolic diseases, evaluating cows (scoring body condition, manure, and lameness), metabolic blood profiles, and feeding behavior were discussed. Educational materials were delivered through in-class lectures, followed by case-based learning and group discussions. A farm visit and out-of-class assignments were also implemented. Attendees were assessed using pre- and post-tests of knowledge to determine the level of knowledge gained in both nutrition modules. Participants evaluated the program and provided feedback at the conclusion of each module. Veterinarians (100%) reported that the overall program, presentations, and discussions were useful. Attendees found the presented information relevant for their work (agree = 60% and strongly agree = 40%) and of great immediate use to them (neutral = 6.5%, agree = 56%, and strongly agree = 37.5%). The presented materials and the implemented educational delivery methods substantially increased the knowledge level of the attendees (16.9% points increase from pre-test to post-test scores). Importance of feed particle size, ration evaluation, interpreting feed analysis, balancing carbohydrate components, and metabolic profiling in fresh cows were listed as learned concepts that participants could apply in their practices. Results suggested that both nutrition modules were relevant and effective, offering new information with immediate field application. This program has important implications for dairy veterinarians because they serve as a vital source of information for dairy producers.     

Opinions and practices of wisconsin dairy producers about biosecurity and animal well-being

The objective of this study was to characterize opinions and practices of Wisconsin dairy producers about biosecurity and animal wellbeing. Wisconsin dairy producers were surveyed using a mailed questionnaire and responder herds were categorized based on the number of lactating cows: very small herds (≤50 lactating cows; n = 279); small herds (51 to 100 lactating cows; n = 202); medium herds (101 to 200 lactating cows; n = 42); and large herds (>200 lactating cows; n = 37). Producers from large herds adopted more biosecurity practices than those from small herds, but biosecurity risks were common. Almost half of the responders indicated that they purchased cattle, but few (49.4%) performed diagnostic testing of those cattle. The frequency of diagnostic testing and examination of purchased cattle increased with herd size. Producers generally (80%) believed that they used the “right amount” of antibiotics, but the use of written treatment protocols increased with herd size. Producers from large and medium herds reported much higher usage of computerized (65.7 and 17.5%, respectively) and paper records (42.9 and 22.5%, respectively) compared with producers from smaller herds. Almost all (92.6%) believed that Johne's disease was an important issue for the dairy industry, but only 9% had enrolled in the official Wisconsin control program. Most producers (88.6%) believed that dehorning caused at least a small amount of pain, but the majority (81%) did not use local anesthetics. Producers minimized risks with which they were most familiar. Drinking raw milk was not considered a human health risk by almost half the responders, whereas bovine spongiform encephalopathy was considered “no risk” to only 37%. Raw milk was consumed by more than 60%, but regular consumption of raw milk decreased from 47.7% (very small herds) to 24.3% (large herds); perception of the risk of raw milk increased from 46.2% (very small herds) to 56.8% (large herds) with herd size. Larger farms had more knowledge of personal health risks related to zoonotic pathogens. Overall, most management practices were associated with herd size, but many beliefs regarding important dairy farm issues were consistent.     

Short communication: Correlations between udder morphology, milk yield, and milking ability with different milking frequencies in dairy goats

Tinerfeñ a breed goats were assigned to 2 experimental herds and milked once (n = 28) or twice (n = 24) daily to study correlations between udder morphology, milk yield, and milking ability during the middle stage of the first lactation. Pearson correlation coefficients were significantly higher between yield and measures of udder globulousness (udder volume, r = 0.79 and r = 0.59; perimeter of insertion of the udder, r = 0.47 and r = 0.37; distance between teats, r = 0.77 and r = 0.28, for goats milked once and twice daily, respectively) than for length parameters (cistern floor distance, r = 0.40 and r = −0.29; udder depth, r = −0.20 and r = 0.20). The globulousness of the udder was correlated with easier milking ability, as shown by milk fractioning (r = 0.49 to 0.70) and milk flow measures (r = 0.32 to 0.49). The results showed that the globulousness of the udder is more important than length measurements in assessing milk yield and milking ability.     

Factors affecting the lactoferrin concentration in bovine milk

Lactoferrin (LF) concentrations in the milk with different levels of the somatic cell count score were examined using an ELISA to determine whether milk LF concentration is influenced by parity of the cow, stage of lactation, and the somatic cell count. The study animals were 198 Chinese Holstein cows randomly chosen from more than 1,600 cows in 4 dairy farms in the Beijing area. The cows had shown no sign of mastitis for 2 mo. Daily milk production was recorded, and milk samples were taken from individual cow samples. The LF concentration varied between 31.78 and 485.63 μg/mL in milk from normal animals. Lactoferrin was significantly associated with stage of lactation (r = 0.557) and daily milk production (r = −0.472). Nevertheless, there was no significant relationship with parity. Moreover, milk LF concentration tended to be correlated with the somatic cell count score (r = 0.375). This finding suggests that milk LF may be helpful as an indicator for intramammary infection in dairy cows.     

Short communication: Repeatability of differential goat bulk milk culture and associations with somatic cell count, total bacterial count, and standard plate count

The aims of this study were to assess how different bacterial groups in bulk milk are related to bulk milk somatic cell count (SCC), bulk milk total bacterial count (TBC), and bulk milk standard plate count (SPC) and to measure the repeatability of bulk milk culturing. On 53 Dutch dairy goat farms, 3 bulk milk samples were collected at intervals of 2 wk. The samples were cultured for SPC, coliform count, and staphylococcal count and for the presence of Staphylococcus aureus. Furthermore, SCC (Fossomatic 5000, Foss, Hillerød, Denmark) and TBC (BactoScan FC 150, Foss) were measured. Staphylococcal count was correlated to SCC (r = 0.40), TBC (r = 0.51), and SPC (r = 0.53). Coliform count was correlated to TBC (r = 0.33), but not to any of the other variables. Staphylococcus aureus did not correlate to SCC. The contribution of the staphylococcal count to the SPC was 31%, whereas the coliform count comprised only 1% of the SPC. The agreement of the repeated measurements was low. This study indicates that staphylococci in goat bulk milk are related to SCC and make a significant contribution to SPC. Because of the high variation in bacterial counts, repeated sampling is necessary to draw valid conclusions from bulk milk culturing.     

Microbiological quality and somatic cell count in bulk milk of dromedary camels (Camelus dromedarius): Descriptive statistics,correlations, and factors of variation

The objectives of the present study were to monitor the microbiological quality and somatic cell count (SCC) of bulk tank milk at the world’s first large-scale camel dairy farm for a 2-yr period, to compare the results of 2 methods for the enumeration of SCC, to evaluate correlation among milk quality indicators, and to determine the effect of specific factors (year, season, stage of lactation, and level of production) on milk quality indicators. The study was conducted from January 2008 to January 2010. Total viable count (TVC), coliform count (CC), California Mastitis Test (CMT) score, and SCC were determined from daily bulk milk samples. Somatic cell count was measured by using a direct microscopic method and with an automatic cell counter. In addition, production parameters [total daily milk production (TDM, kg), number of milking camels (NMC), average milk per camel (AMC, kg)] and stage of lactation (average postpartum days, PPD) were recorded for each test day. A strong correlation (r = 0.33) was found between the 2 methods for SCC enumeration; however, values derived using the microscopic method were higher. The geometric means of SCC and TVC were 394 × 10³ cells/mL and 5,157 cfu/mL during the observation period, respectively. Somatic cell count was >500 × 10³ cells/mL on 14.6% (106/725) and TVC was >10 × 10³ cfu/mL on 4.0% (30/742) of the test days. Both milk quality indicators had a distinct seasonal pattern. For log SCC, the mean was lowest in summer and highest in autumn. The seasonal pattern of log TVC was slightly different, with the lowest values being recorded during the spring. The monthly mean TVC pattern showed a clear difference between years. Coliform count was <10 cfu/mL in most of the samples (709/742, 95.6%). A positive correlation was found between log SCC and log TVC (r = 0.32), between log SCC and CMT score (r = 0.26), and between log TVC and CC in yr 1 (r = 0.30). All production parameters and stage of lactation showed strong seasonal variation. Log SCC was negatively correlated with TDM (r = −0.35), AMC (r = −0.37), and NMC (r = −0.15) and positively correlated with PPD (r = 0.40). Log TVC had a negative correlation with AMC (r = −0.40) but a positive correlation with NMC (r = 0.32), TDM (r = 0.16), and PPD (r = 0.45). The linear mixed model with stepwise variable selection showed that the main sources of log SCC variation were PPD, TDM, PPD × season, and season. For log TVC, the same factors and year contributed to the variation.     

Invited review: Antibiotic treatment of metritis in dairy cows: A systematic approach

Acute puerperal metritis (APM) is an acute systemic illness with fever ≥39.5°C and signs of toxemia due to an infection of the uterus occurring within 21 d after parturition. Because of the infectious nature of APM, antibiotics are considered beneficial for its treatment. Each use of an antimicrobial drug, however, is associated with selective pressure for the emergence of resistant bacteria. Hence, there is a significant need to encourage prudent use of antibiotics and alternative therapies to antibiotics. Therefore, the objective of this study was to systematically review the current literature on treatment of APM. A comprehensive and systematic literature search was conducted utilizing the PubMed and CAB Abstracts databases to identify literature focusing on the antibiotic therapy of puerperal metritis in the cow. After application of specific exclusion criteria, 21 publications comprising 23 trials remained for final evaluation. Data extraction revealed that the majority of the studies (n = 19) were attributable to the highest evidence level. Of 21 studies controlled, 11 had an untreated group and 3 a positive control group. The majority of the studies (n = 17) applied ceftiofur for the treatment of APM. Concerning the efficacy of ceftiofur, 7 studies observed clinical improvement, whereas none found improved reproductive performance. Fewer than half of the studies (n = 10) performed a bacteriological examination and only 4 implemented an antibiotic susceptibility test. Also, 3 studies (13.0%) described a self-cure rate per se. Little attention was given to the issue of bacterial resistance (n = 3), the need for reducing the application of antibiotics (n = 2), or guidelines for prudent use of antibiotics (n = 1). Our findings demonstrate that implementation of bacteriological examinations, sensitivity testing, and determination of minimum inhibitory concentrations, as well as reporting and discussion of critical issues (e.g., self-cure rates, resistance, prudent drug use), were suboptimal. On the other hand, the quality of studies on the treatment of APM was good, as indicated by evidence level 1. Nevertheless, more high-quality research considering self-cure rates is necessary to address critical issues related to APM and crucial to the dairy industry, such as resistance, prudent use of antibiotics, animal welfare, and cost-benefit ratios.     

A survey on antibiotic usage in dairy herds in Pennsylvania

A survey was conducted (July 2001 to June 2002) on antibiotic usage of 113 dairy herds from 13 counties in Pennsylvania. Fifty percent of dairy farms surveyed maintained antibiotic treatment records. Only 21% of dairy producers had written plans for treating sick animals. Thirty-two percent of dairy producers sought veterinarian advice before administering antibiotics and on most farms (93%), antibiotics were administered by the owner/manager or designated herdsman. Twenty-four percent of the dairy producers said they always completed the course of antibiotic treatment. Any extra-label use of antibiotics was administered only on the guidelines of a veterinarian on majority of the farms. Comprehensive records from 33 dairy farms indicated that antibiotic usage was largest for calves with enteritis (36%) followed by pneumonia in calves (25%) and foot rot in cattle (16%). Twenty-four antibiotics including beta-lactams, spectinomycin, florfenicol, and tetra-cyclines were used on these farms. Beta-lactam antibiotics were used mostly for dry cow therapy, clinical mastitis, and on some farms for pneumonia and metritis. On 18% of the dairy herds surveyed, ceftiofur was used in an extra-label manner to treat mastitis in lactating cattle. On 70% of farms, calves were fed medicated milk replacers containing oxytetracycline and neomycin. The results of this study suggest that antibiotics are used extensively on dairy herds for both therapeutic and prophylactic purposes. Beta-lactams and tetracyclines were the most widely used antibiotics. There is considerable variation in the management practices associated with antibiotic use on dairy farms. It is anticipated that the findings of this survey will permit developing new strategies for prudent use of antibiotics on dairy herds.     

Strategies to improve the therapy of retained fetal membranes in dairy cows

In this field trial, a protocol for the treatment of retained fetal membranes (RFM) without any intrauterine therapy was compared with 3 protocols based on the intrauterine use of antibiotic pills (AP), the manual removal (MR) of the fetal membranes, or the combination of both (PR). The study was conducted on 5 commercial dairy farms in Germany. Cows with RFM for at least 24 h after calving were assigned to 1 of 4 treatment groups. Cows of all groups with a rectal temperature ≥ 39.5°C received a systemic antibiotic treatment with ceftiofur (1 mg/kg per d) for 3 to 5 consecutive days. In case of continued fever after 5 treatments, cows received a different antibiotic as an escape therapy. In the reference group (REF; n = 131), cows did not receive any additional treatment. All cows in group AP (n = 119) received intrauterine treatment with antibiotic pills consisting of 1,000 mg of ampicillin and 1,000 mg of cloxacillin for 3 consecutive days. In group MR (n = 121), an attempt was made to remove the fetal membranes manually, but uterine pills were not administered. In group PR (n = 130), an attempt was made to remove the fetal membranes manually and all cows received a local antibiotic treatment as in group AP. All cows received 2 doses of 25 mg of PGF_2α: one dose between 18 and 24 d and another between 32 and 38 d postpartum. Statistical analyses were performed using binary logistic regression models and survival analyses with group REF as reference. Of all animals, 79.8% had a body temperature of ≥ 39.5°C at least once within 10 d postpartum and were treated with ceftiofur. Occurrence of fever within 10 d postpartum was significantly lower in groups AP and PR compared with reference group REF, but was not different between groups MR and REF. Risk of receiving an escape therapy in case of fever after 5 treatments with ceftiofur did not differ among groups. Reproductive performance measures did not differ significantly between group REF and any of the comparison groups. Compared with a treatment protocol based only on systemic treatment with antibiotics for cows with a fever, neither intrauterine antibiotics nor manual removal of fetal membranes alone or in combination reduced proportions of cows needing an escape therapy nor did those treatments improve reproductive measures in the current lactation. Systemic treatment alone based on elevated rectal temperature was effective and reduced use of antibiotics compared with therapies that included intrauterine antibiotics.     

Management practices and reported antimicrobial usage on conventional and organic dairy farms

The primary objective was to compare reported antimicrobial usage between conventional and organic dairy farms. A secondary objective was to contrast selected management characteristics of conventional and organic dairy herds. A questionnaire was administered on site to selected dairy farmers located in Michigan, Minnesota, New York, and Wisconsin. Organic herds (n = 32) were smaller and produced less milk than conventional herds (n = 99). Lactating cows in organic dairies were more likely to be housed in tie stalls, whereas most conventional dairies housed cows in free stalls and milked in a parlor. Total mixed rations and purchased feeds were used on more conventional dairy farms compared with organic dairy farms. Conventional dairy producers were more likely to use advice from veterinarians for recommendations of treatment, and organic dairy producers were more likely to rely on advice from other farmers. Based on recall of antibiotic usage in the previous 60 d, 5.1, 84.9, 9.1, and 0.9% of farmers with conventional herds reported treatment of none, 1 to 10%, 11 to 25%, and >25% of milk cows, respectively. Most organic farmers (90.6%) reported no antibiotic treatments of milk cows, whereas 9.4% reported treating 1 to 10% of milk cows. Ceftiofur was the most commonly reported antibiotic for both farm types. Milk replacer containing antibiotics was reportedly used on 49.5% of conventional herds but only on one organic herd (3.1%). Antibiotics were used in heifer calves on 74.7% of conventional herds versus 21.9% of organic herds. Antibiotics to treat mastitis were used on 79.8% of conventional herds but on none of the organic herds. Most organic farms were in compliance with standards in advance of implementation of regulations.     

Lactose in blood plasma and the ability of dairy cows to tolerate once-daily milking in terms of milk loss and milk recovery

This experiment described the variability among cows with the aim of studying the ability of dairy cows to tolerate once-daily milking (ODM) in terms of milk losses and milk recoveries observed when cows are switched from twice- to once-daily milking and then back to twice-daily milking (TDM). It also aimed to investigate whether or not lactose in blood plasma, which indicates the mammary epithelium permeability, is correlated with milk losses and recoveries and, consequently, a potential candidate assessor of dairy cow tolerance to ODM. The study used 86 crossbred dairy cows (Holstein × Normande) split into 5 groups over 2 yr. The trial consisted of 3 successive periods: a 1-wk control period of TDM, then 3 wk of ODM, followed by 2 wk of TDM. Blood samples were collected 1 to 1.5 h before the morning milking and 5 to 6 h after milking on d −3, 0, 1, 3, 7, 21, 23, and 28, where d 0 is the last d of the control period. Milk losses measured as kilograms per day were higher in cows with highest control-period milk yields (r = −0.66). When expressed in relative terms (%), milk losses were weakly correlated with the control-period milk yield (r = −0.22). When switched back to TDM, cows recovered only 47% of the milk lost. Milk recovery (kg/d) was weakly correlated with control milk yield (r = 0.34) and not correlated with ODM milk yield. Milk recovery was correlated with milk yield losses: the higher the milk yield losses (kg/d or %), the higher the milk recovery (kg/d; r = −0.59 and −0.52, respectively). Rate of milk recovery expressed as the quantity of milk recovered per kilogram of milk lost, was not correlated with milk loss expressed as a percentage. This means that to be considered well-adapted to ODM scheduling, a cow must be well adapted to milk loss, and be well adapted to milk recovery. Blood plasma lactose concentration (log₁₀-transformed data) was not correlated with milk production levels in either control, ODM, or back-to-TDM periods. It was poorly correlated with milk loss but was positively correlated with milk recovery (kg/d) and rate of milk recovery. We conclude that blood plasma lactose needs to be coupled with other indicators for evaluating dairy cow tolerance to ODM.     

Biofilm-producing ability of Staphylococcus aureus isolates from Brazilian dairy farms

This study aimed to investigate the in silico biofilm production ability of Staphylococcus aureus strains isolated from milking parlor environments on dairy farms from São Paulo, Brazil. The Staph. aureus isolates were obtained from 849 samples collected on dairy farms, as follows: milk from individual cows with subclinical mastitis or history of the disease (n = 220); milk from bulk tank (n = 120); surfaces of milking machines and utensils (n = 389); and milk handlers (n = 120). Thirty-one Staph. aureus isolates were obtained and categorized as pulsotypes by pulsed-field gel electrophoresis and submitted to assays for biofilm formation on polystyrene, stainless steel, rubber, and silicone surfaces. Fourteen (45.2%) pulsotypes were considered producers of biofilm on the polystyrene microplate assay, whereas 13 (41.9%) and 12 (38.7%) pulsotypes were biofilm producers on stainless steel and rubber, respectively. None of the pulsotypes evaluated produced biofilms on silicone. Approximately 45% of Staph. aureus pulsotypes isolated from different sources on dairy farms showed the ability to produce biofilms in at least one assay, indicating possible persistence of this pathogen in the milking environment. The potential involvement of Staph. aureus in subclinical mastitis cases and its occurrence in milk for human consumption emphasize the need to improve hygiene practices to prevent biofilm formation on the farms studied.     

Herd-level relationship between antimicrobial use and presence or absence of antimicrobial resistance in gram-negative bovine mastitis pathogens on Canadian dairy farms

Concurrent data on antimicrobial use (AMU) and resistance are needed to contain antimicrobial resistance (AMR) in bacteria. The present study examined a herd-level association between AMU and AMR in Escherichia coli (n = 394) and Klebsiella species (n = 139) isolated from bovine intramammary infections and mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Antimicrobial use data were collected using inventory of empty antimicrobial containers and antimicrobial drug use rate was calculated to quantify herd-level AMU. Minimum inhibitory concentrations (MIC) were determined using Sensititre National Antimicrobial Resistance Monitoring System (NARMS) gram-negative MIC plate (Trek Diagnostic Systems Inc., Cleveland, OH). Isolates were classified as susceptible, intermediate, or resistant. Intermediate and resistant category isolates were combined to form an AMR category, and multivariable logistic regression models were built to determine herd-level odds of AMR to tetracycline, ampicillin, cefoxitin, chloramphenicol, trimethoprim-sulfamethoxazole combination, sulfisoxazole, streptomycin and kanamycin in E. coli isolates. In the case of Klebsiella species isolates, logistic regression models were built for tetracycline and sulfisoxazole; however, no associations between AMU and AMR in Klebsiella species were observed. Ampicillin-intermediate or -resistant E. coli isolates were associated with herds that used intramammarily administered cloxacillin, penicillin-novobiocin combination, and cephapirin used for dry cow therapy [odds ratios (OR) = 26, 32, and 189, respectively], and intramammary ceftiofur administered for lactating cow therapy and systemically administered penicillin (OR = 162 and 2.7, respectively). Use of systemically administered penicillin on a dairy farm was associated with tetracycline and streptomycin-intermediate or -resistant E. coli isolates (OR = 5.6 and 2.8, respectively). Use of cephapirin and cloxacillin administered intramammarily for dry cow therapy was associated with increasing odds of having at least 1 kanamycin-intermediate or -resistant E. coli isolate at a farm (OR = 8.7 and 9.3, respectively). Use of systemically administered tetracycline and ceftiofur was associated with cefoxitin-intermediate or -resistant E. coli (OR = 0.13 and 0.16, respectively); however, the odds of a dairy herd having at least 1 cefoxitin-intermediate or -resistant E. coli isolate due to systemically administered ceftiofur increased with increasing average herd parity (OR = 3.1). Association between herd-level AMU and AMR in bovine mastitis coliforms was observed for certain antimicrobials. Differences in AMR between different barn types and geographical regions were not observed.     

Comparison of selected animal observations and management practices used to assess welfare of calves and adult dairy cows on organic and conventional dairy farms

Differences in adoption of selected practices used in welfare assessment and audit programs were contrasted among organic (ORG; n = 192) herds and similarly sized conventional grazing herds (CON-GR; n = 36), and conventional nongrazing herds (CON-NG; n = 64). Criteria from 3 programs were assessed: American Humane Association Animal Welfare Standards for Dairy Cattle, Farmers Assuring Responsible Management (FARM), and the Canadian Codes of Practice (CCP). Data were collected by trained study personnel during a herd visit and included information about neonatal care, dehorning, pain relief, calf nutrition, weaning, record keeping, use of veterinarians, and animal observations. Associations of management type (ORG, CON-GR, or CON-NG) with adoption of selected practice were assessed. Almost all farms (97%) met criteria suggested for age at weaning but fewer CON-NG farmers weaned calves at ≥5 wk of age compared with ORG and CON-GR farmers. Only 23% of farms met program requirements for use of pain relief during dehorning, and fewer CON-NG farmers used pain relief for calves after dehorning compared with ORG and CON-GR farmers. Calves on ORG farms were fed a greater volume of milk and were weaned at an older age than calves on CON-GR and CON-NG farms. Calves on CON-GR farms were dehorned at a younger age compared with calves on ORG and CON-NG farms. The calving area was shared with lactating cows for a larger proportion of ORG herds compared with conventional herds. About 30% of herds met welfare program criteria for body condition score but only about 20% met criteria for animal hygiene scores. The least proportion of cows with hock lesions was observed on ORG farms. Regular use of veterinarians was infrequent for ORG herds. Results of this study indicate that most of the organic and conventional farms enrolled in this study would have been unlikely to achieve many criteria of audit and assessment programs currently used in the US dairy industry.     

Perception of the importance of human-animal interactions on cattle flow and worker safety on Minnesota dairy farms

Proper cattle-handling techniques (stockmanship) are important to ensure calm animals and a safe work environment for dairy workers on farm. The objectives of this study were to (1) assess Minnesota dairy herd owners’ attitudes toward stockmanship, its perceived importance for cow comfort and worker health, and the establishment of calm cattle movement; and (2) identify current resources and methods of stockmanship training on Minnesota dairy farms. A stratified-random sample of Minnesota dairy farmers were contacted via mail to participate in a 28-question survey. One hundred eight bovine dairy producers participated. Most commonly, respondents learned their cattle handling skills from family members (42.6%) and 29.9% of producers had participated in previous stockmanship training. Producers thought that the skill of the human handler was the most important factor in establishing good cattle flow. Cattle-handling techniques was the third most common topic for new-employee orientation after training in milking parlor protocols and milking parlor disinfection. Time limitations and language barrier were considered serious challenges for worker training. Work-related injuries were responsible for lost work days in the previous year in 13.3% of dairy herds and 73.3% of those injuries occurred while working with cattle. Producers perceived that cattle-related injuries were predominantly the handler’s fault: either because of not paying enough attention to the animal or due to poor cattle handling skills. Facility design was considered the least important for the occurrence of worker injuries. Although no causal inference can be made, herds that had workers who had previously participated in stockmanship training had a 810 ± 378 kg (mean ± standard error of the mean) higher rolling herd average than those that did not, even after adjusting for herd size and bulk tank somatic cell count. However, 50% of respondents were not interested in attending future stockmanship training sessions. In conclusion, cattle handling skills are considered important by Minnesota dairy producers to ensure worker safety and cow flow. Limited availability of time, language barrier, and a perceived lack of training materials were considered challenges during the training of workers on farms.     

Dairy producer satisfaction and knowledge transfer with the veterinary-administered risk assessment and management plan in a voluntary Johne's disease control program

The Atlantic Johne's Disease Initiative (AJDI) aims to control Mycobacterium avium ssp. paratuberculosis infection by using veterinary-administered risk assessments to identify high-risk management practices and prompt changes in management behavior. Objectives for this study were to measure producer satisfaction with the veterinary-administered risk assessment and management plan (RAMP) process in a voluntary Johne's disease (JD) control program, compare RAMP-specific satisfaction results based on herd JD status, and measure knowledge transfer from certified veterinarians to producers during the RAMP. A satisfaction questionnaire was adapted to the RAMP process in the AJDI to measure producer satisfaction. The questionnaire included 9 RAMP-specific producer satisfaction items, 1 global RAMP satisfaction item, and 16 questions to assess producer knowledge and knowledge translation about JD, bovine viral diarrhea (BVD), and bovine leukosis virus (BLV) during the RAMP (BVD and BLV used for comparison purposes). A total of 133 dairy producers in the AJDI (79.6% response rate) completed the questionnaire by telephone. The RAMP-specific satisfaction was high among the AJDI producers surveyed, and these results were not found to differ based on herd JD status. The lowest satisfaction scores and the highest number of “unable to assess” responses were for the item relating to cost. Factors that contributed to RAMP-specific producer satisfaction were not identified from the demographic and herd information available in this study. The knowledge scores indicated moderate knowledge about JD and fair knowledge about BVD and BLV. Evidence of knowledge translation from the RAMP was mixed in this study. Bovine viral diarrhea knowledge scores were not found to differ based on whether or not the certified veterinarian discussed BVD during the preceding RAMP, but BLV knowledge scores were higher among dairy producers that discussed BLV during the preceding RAMP. Strengths and gaps in producer knowledge about these 3 infectious diseases were identified. By using this producer questionnaire, interventions aimed at improving the content, delivery, and satisfaction of RAMP in JD control programs, such as the AJDI, can be developed.     

Evaluation of a system for monitoring rumination in heifers and calves

The Hi-Tag electronic rumination-monitoring system (SCR Engineers Ltd., Netanya, Israel), based on capturing audio recordings, provides a reasonable measure of rumination time in dairy cows, but has not been validated for milk-fed or weaned heifers. The objective of this study was to validate the Hi-Tag rumination-monitoring system in heifers and calves and to assess whether suckling from a teat interfered with recording from this system. Assessments of 2 independent observers were highly correlated (r = 0.99, n = 20), indicating that direct visual observations provide a useful standard. Measures from the Hi-Tag system were validated by comparing values with those from a single human observer, using observations from three 2-h intervals from 35 Holstein calves and heifers aged 4, 6, and 9 wk and 3, 6, and 9 mo, respectively. In 9-mo-old heifers, rumination times obtained from the electronic system were highly correlated with visual observations (r = 0.88, R² = 0.77, n = 15), and the mean difference was minor (−4 ± 8 min/2-h interval). The accuracy of data from the automated system decreased when used on heifers less than 9 mo old. Suckling did not interfere with the electronic system (r = −0.1, n = 18). These results indicate that the Hi-Tag system is an accurate tool for monitoring rumination behavior in Holstein Friesian heifers from the age of 9 mo.     

Short communication: Automatic detection of social competition using an electronic feeding system

The objective of this study was to determine if data derived from a system that electronically monitors feeding behavior could be used to identify competitive interactions of dairy cows at the feed bunk. A short interval between successive feeding events of 2 cows at 1 feed bin was predicted to be associated with a competitive replacement: when one cow displaced a feeding cow and then took her position at the bin. To identify the interval between feeding events that best predicted these replacement events, the feeding activity of 5 Holstein dairy cows was monitored using an electronic feeding system and video recordings. The number of times a cow was replaced at the feed bunk over 3 consecutive 24-h periods was determined using video analysis and these events were paired with the corresponding feeding events recorded by an electronic feeding system (Roughage Intake Control system; Insentec B.V., Marknesse, the Netherlands). A pooled analysis of all 5 cows showed that the optimal interval for predicting replacements at the feed bunk was 26 s (sensitivity = 86% and specificity = 82%); this interval was termed the replacement criterion. This criterion was then applied to feeding data from a sample of 24 independent Holstein dairy cows, each observed for 3 d during the week following calving. Video had previously been used to measure the number of times each cow was an actor and reactor of a displacement (when one cow displaced a feeding cow but did not necessarily take her position at the bin). Despite the differences in measures, the number of replacements (as estimated by our algorithm) was positively correlated with the number of displacements [as measured using video; correlation coefficient (r) = 0.63 as actor, r = 0.69 as reactor]. Estimates of an index of success in competitive interactions (number of times actor/number of times actor = number of times reactor) generated using the 2 methods were highly correlated (r = 0.94). These results suggest that competitive behavior at the feed bunk can be automatically quantified using data derived from an electronic feeding system.