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There has been a rapid increase in adoption of recycled manure solids (RMS) as bedding in Midwest dairy herds over the past 10 to 15 years due to perceived advantages such as cost and availability. Several studies have reported increased bedding bacteria counts (BBC) and increased mastitis risk in herds using RMS as compared to inorganic or organic non-manure materials. Although many RMS dairies use either green/raw (GRN) solids or solids first processed through an anaerobic methane digester (DIG), some herds have adopted mechanical composters (COM) or dryers (DRY) in an effort to lower BBC and control mastitis. Research is needed to evaluate potential benefits and costs of adopting these technologies. This research team initiated a study to evaluate udder health, air quality, antimicrobial resistance in solids, and economics, for herds using different RMS processing methods. The objective of this portion of the study was to investigate if method of processing RMS is associated with udder health and milk production on Midwest dairy farms., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2020

There has been a rapid increase in adoption of recycled manure solids (RMS) as bedding in Midwest dairy herds over the past 10 to 15 years due to perceived advantages such as cost and availability. However, several studies have reported increased bedding bacteria counts (BBC) and increased mastitis risk in herds using RMS as compared to inorganic or organic non-manure materials. Although many RMS dairies use either green/raw (GRN) solids or solids first processed through an anaerobic methane digester (DIG), some herds have adopted mechanical composters (COM) or dryers (DRY) in an effort to lower BBC and control mastitis. Research is needed to evaluate potential benefits and costs of adopting these technologies. This research team initiated a study to evaluate udder health, air quality, antimicrobial resistance in solids, and economics, for herds using different RMS processing methods. In a companion abstract, we determined that use of COM or DRY was associated with improved udder health and milk production as compared to GRN. In this abstract, we explore if these benefits are likely to be explained by differences in bedding characteristics, such as BBC, for the 4 processing systems investigated. The objective of this portion of the study is to investigate if method of processing RMS is associated with BBC in ready-to-use (RTU) RMS on Midwest dairy farms., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2020

Though critical to calf health and growth, colostrum exposure of dairy calves to infectious agents, potentially resulting in calfhood illness and/or reduced absorption of colostral antibodies. While FDA-approved preservatives such as potassium sorbate may represent 1 approach to reduce bacterial proliferation in stored colostrum or milk, efficacy studies are relatively limited. Objectives of this study were to describe the effect of a stabilized liquid potassium sorbate preservative product (Dam Fresh™, Solution BioSciences, Inc (SBS), Inc. Morristown, NJ) on 1) bacterial proliferation in bovine colostrum and milk when stored by refrigeration and at room temperature, and 2) immunoglobulin G (IgG) levels in colostrum. We hypothesized that the preservative would reduce bacterial proliferation in stored milk and colostrum while having no negative effect on colostrum IgG levels., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2020

The objectives of this study were to perform an in-lab validation of the Minnesota Easy Culture System II bi-plate method as compared to standardized laboratory culture methods and to describe inter-reader agreement for bi-plate culture results., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2006

Results from this study show that heattreated colostrum can be successfully fed on commercial dairy farms to reduce pathogen exposure without harming passive transfer in newborn calves., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2006

The objectives of this study were to perform an in-lab validation of the Minnesota Easy Culture System II tri-plate method as compared to standardized laboratory culture methods and to describe inter-reader agreement for tri-plate culture results., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2006

There is an opportunity to reduce antibiotic (ABX) use at dry-off in US dairy farms, as approximately 80% of herds practice blanket dry cow therapy (BDCT), despite most quarters (~80%) being uninfected at that time. Selective dry cow therapy (SDCT) strategies use screening tests to determine which quarters or cows require ABX treatment at dry-off. A small number of trials conducted in North America recently found that SDCT reduced ABX use by up to 60% without negatively impacting udder health, culling risk or milk production when compared to BDCT. However, more research is needed to validate SDCT before it can be widely implemented. The objective of this study was to compare 2 SDCT approaches (Culture-based or Algorithm-based) against BDCT in a multiherd randomized, positively controlled, clinical trial for the following outcomes; reduction in ABX use at dry-off, clinical mastitis (CM) risk, culling risk, milk yield, and somatic cell count (SCC) in the first 120 days in milk (DIM)., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2019

The objective of this study was to complete a positive-control, natural exposure, noninferiority design field study to test the efficacy of a novel glycolic acid-based postmilking teat disinfectant as compared with a previously proven iodine-based postmilking teat disinfectant (positive control). The primary outcome of interest was the effect of treatment on incidence of new intramammary infections. Secondary outcomes included the effect of treatment on prevalence of infection, somatic cell count, and teat condition. After blocking by parity, approximately 300 early- to mid-lactation cows on a large Wisconsin dairy farm were randomly assigned to 1 of 2 groups. For a 12-wk period between May and August 2014, the 2 groups were dipped after each milking with either the experimental (EX) or positive control (PC) product. Individual quarters were sampled to establish bacteriological infection status at the beginning of the study, and every 2 wk thereafter, by use of a 2-stage process evaluating somatic cell count (SCC), and then culturing milk samples only when SCC exceeded a parity-specific threshold. Teat condition scoring was completed at the beginning of the study and on wk 4, 8, and 12. Mixed logistic regression was used to evaluate the effect of treatment on dichotomous outcome measures including the odds of acquiring a new infection during a given 2-wk sampling interval (incidence), the odds for presence of infection at sampling (prevalence), and odds for a normal teat skin condition score. Mixed linear regression was used to evaluate the effect of treatment on somatic cell count. For the noninferiority analysis, the upper bound of the 95% confidence interval for the difference in new infection rate between the 2 treatments (EX - PC), had to be to the left of the critical value d (0.035) to conclude that EX was noninferior relative to PC with respect to risk for new infections. Results showed that the incidence of new infections was not different for quarters dipped with EX (3.2%) as compared with PC (4.2%). Similarly, the prevalence of infection tended to be lower for quarters dipped with EX (3.92%) as compared with PC (5.03%). No overall difference was found between treatments when evaluating somatic cell count measures and teat condition scores. Because the upper bound of the 95% confidence interval of the new IMI rate difference was smaller than the predefined noninferiority limit, it was concluded that the experimental product was not inferior compared with the positive control. As such, the glycolic acid-based teat disinfectant evaluated in this study can be considered an effective postmilking teat disinfectant, as well as safe, in so far as the product was not irritating to teat skin and did not negatively affect skin condition measures, as compared with the positive control group.

The major objective of this multi-herd observational study was to describe the relationship between BBC and udder health and to identify cutpoints for interpreting bedding culture results. A secondary objective was to identify bedding characteristics and bedding management strategies that are associated with lower BBC and improved udder health. This abstract presents preliminary results describing some of the relationships between bedding bacteria count (BBC), bedding characteristics, and udder health for 4 bedding materials: new sand (NS), reclaimed sand (RS), manure solids (MS), or other organic bedding materials (OB)., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2018

Pre-milking cleaning and teat disinfection is a common practice on US dairy farms. Studies have shown that towel laundering practices can influence levels of bacteria in towels that are used in teat preparation. Consequently, some laboratories offer towel culture services, which are used by practitioners to evaluate the effectiveness of towel laundering systems. However, the impact of poor towel hygiene on udder health is not well understood, and few surveys have been conducted to describe towel hygiene, or management strategies to improve towel hygiene, on US dairy farms. The objectives of this cross-sectional study are to: 1) describe the levels of bacteria in udder towels on US dairy farms, 2) describe associations between towel total bacteria count (TBC) and intramammary infection (IMI) prevalence for individual pathogens and specific pathogen groups in late lactation cows, 3) identify laundering-related risk factors for high towel bacteria count, and 4) identify critical levels of bacteria in towels, that might be used as cut-points to guide practitioners when interpreting towel culture reports. This study is ongoing, with results currently being assembled. In this abstract we report preliminary results., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2018

Dystocia is a significant issue in Holstein cattle. Injury, pain, inflammation, acidosis, and low overall vitality are common effects seen in calves that survive. In humans, a standard vigor scoring system has been used for over 60 years. This score is based on Appearance, Pulse, Grimace, Activity, and Respiration (Apgar Score). A validated method of assessment of newborn calf vitality has not been developed. Also, pain management in newborn calves after dystocia is not often addressed by veterinarians or producers. It was the overall objective of this research to identify the various effects of calving difficulty on newborn dairy calves, and to relate these effects to easily measurable signs of reduced vigor. These signs were quantified into a VIGOR Scoring System. Also, methods to reduce pain, inflammation, and acidosis resulting from dystocia were investigated., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2018

Pain management in newborn calves after dystocia and assisted calving is still not addressed by most producers or veterinarians. The calf VIGOR scoring system, developed at the University of Guelph, was designed to be applied within minutes after birth to assesses Visual appearance, Initiation of movement, General responsiveness, Oxygenation, and heart and respiration Rates in calves. The VIGOR scoring system was designed to identify high risk/low vigor calves for the purpose of applying interventions to improve vigor and survivability. In different studies conducted at the University of Guelph it was reported that providing pain management with a non-steroidal anti-inflammatory (meloxicam), shortly after birth, may improve calf vitality, health and performance outcomes, particularly in calves experiencing dystocia. The objective of this study was to conduct a randomized controlled trial to evaluate the effect of implementing a novel program that includes assessment of newborns using the VIGOR scoring system followed by provision of meloxicam to calves with low vigor scores, on outcomes reflecting calf well-being and health., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2018

Many cows acquire subclinical intramammary infections (IMI) during lactation, necessitating antimicrobial treatment at dry-off (dry cow therapy). If the dairy industry moves toward the adoption of selective dry cow therapy, one essential strategy to reduce mastitis-associated antimicrobial use at dry off will be to reduce the incidence of new IMI during lactation. One important source of mastitis-causing pathogens is bedding. However studies are needed to investigate the association between bedding management, bedding bacteria count (BBC), and IMI risk in late lactation cows. The objectives of this prospective cross-sectional study are to: 1) describe associations between BBC and IMI prevalence for individual pathogens and specific pathogen groups in late lactation cows, 2) identify bedding-related risk factors for high BBC, and 3) identify critical levels of bacteria in bedding that might be used as cut-points to guide practitioners when interpreting BBC reports. This study is ongoing, with winter 2018 results currently being assembled., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2018

Bovine respiratory disease (BRD) is an important illness of dairy replacement heifer calves that has substantial impacts on growth, survival and profitability. The objective of this research was to determine the effects of one or two doses of a commercial, multivalent, (MLV) vaccine, administered to heifer calves prior to weaning. It was hypothesized that vaccination would reduce the incidence of BRD and that two doses would be more efficacious than one., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2010

The dairy industry must develop mastitis control practices that can use antimicrobials judiciously while maintaining or improving udder health. One opportunity is the adoption of selective dry cow therapy (SDCT) programs that treat only infected quarters or cows. Another approach may be to identify and apply selective treatment to infected quarters soon after calving. However, for such programs to be successful, we require on-farm tests with sufficient accuracy and utility to differentiate infected from uninfected quarters or cows. The objective of this study was to describe the diagnostic test characteristics of an automated milk leukocyte differential (MLD) test to identify intramammary infection (IMI) in early-lactation (EL) and late-lactation (LL) quarters and cows., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2016

High levels of bacteria in bedding (bedding bacteria counts; BBC) are associated with increased bacteria loads on teat ends and, in some reports, with an increased risk for environmental mastitis infections. However, relatively few studies have investigated the relationship between BBC and udder health, and science-based guidelines are lacking to interpret BBC culture results in different bedding materials. Therefore, the primary goal of our study is to conduct a multi-state, multi-herd cross-sectional observational study to describe the relationship between bedding bacteria counts and udder health and to identify cutpoints for interpreting BBC data. A secondary objective is to identify bedding characteristics and bedding management strategies that are associated with lower BBC and improved udder health. In this abstract we present preliminary results that describe BBC in new and used bedding samples collected from herds using new sand (NS), reclaimed sand (RS), manure solids (MS) or other organic bedding materials (OB)., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2017

Group housing of dairy calves offers several advantages for dairy producers, yet calves housed in these systems have an increased risk of disease and it can be more challenging to detect a sick calf in a group. Fever is a widely used indicator of infectious diseases in dairy calves and often accompanies the two most common calf hood morbidities, diarrhea (DIA) and respiratory (RESP) disease. Indwelling rumen temperature bolus (RTB) systems are newly available for calves, but their utility in a field setting has not been formally evaluated. As a first step towards describing the utility (test characteristics) of this technology to detect morbidity, the objective of this study was to describe the relationship between automatically captured RTB temperatures and morbidity in group housed, pre-weaned dairy calves., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2017

While the level of milk intake from birth to weaning is positively associated with pre-weaning health, growth, and improved milk production in the adult dairy cow, producers are still reluctant to offer large volumes of milk during the first week or two of life due to concerns that increasing the daily allowance too quickly may cause nutritional (milk) scours. However, recent observational studies have reported a positive association between levels of milk consumption in the first days of life and future health events. The objective of this study was to describe the effect of offering a more liberal volume of milk immediately from day 1 of life, as compared to a traditional ramp-up program. We hypothesized that calves offered more milk early in life would not experience more scours, but rather would experience improved health and growth as compared to calves that were slowly ramped up in their daily milk allowance over a period of 7 - 14 days., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2017

The study objective was to evaluate the effects of applying a culture-guided, quarter-level selective dry cow therapy (SDCT) program on udder health and antibiotic usage as compared to blanket dry cow therapy (BDCT). Two days prior to dry-off (DO), 56 cows were randomly assigned to a BDCT or SDCT group and aseptic quarter milk samples were collected for laboratory culture. For cows in the SDCT group, milk from each quarter was also cultured using a rapid culture system, with results recorded as bacterial "growth" or "no growth". On the day of DO, cows in the BDCT group were infused with an antibiotic and an internal teat sealant in all 4 quarters. For cows assigned to the SDCT group, quarters with bacterial growth were infused with an antibiotic plus internal teat sealant, while quarters with no growth were infused with internal teat sealant only. Quarter milk samples were collected days 1 through 7 after calving for laboratory culture, and clinical mastitis events were recorded between DO and 30 days-in-milk. Logistic regression was used to evaluate the effect of treatment on measures of udder health after calving. Results showed no effect of treatment on quarter level risk for presence of infection after calving ( 42.1 % vs 39.6%), cures (82.3% vs 88.0%), or new infection ( 41.5% vs 40.2%) for the SDCT and BDCT group, respectively. Antibiotic use was reduced by 48% in the SDCT group. Results of this pilot study suggest that a culture-guided quarter-level SDCT program can achieve equal udder health compared to BDCT, while significantly reducing antibiotic use at DO., The Bovine Practitioner, Vol. 51, No. 1 (2017 Spring)

Criteria for diagnosing intramammary infections (IMI) have been debated for many years. Factors that may be considered in making a diagnosis include the organism of interest being found on culture, the number of colonies isolated, whether or not the organism was recovered in pure or mixed culture, and whether or not concurrent evidence of inflammation existed (often measured by somatic cell count). However, research using these criteria has been hampered by the lack of a “gold standard” test (i.e., a perfect test against which the criteria can be evaluated) and the need for very large data sets of culture results to have sufficient numbers of quarters with infections with a variety of organisms. This manuscript used 2 large data sets of culture results to evaluate several definitions (sets of criteria) for classifying a quarter as having, or not having an IMI by comparing the results from a single culture to a gold standard diagnosis based on a set of 3 milk samples. The first consisted of 38,376 milk samples from which 25,886 triplicate sets of milk samples taken 1 wk apart were extracted. The second consisted of 784 quarters that were classified as infected or not based on a set of 3 milk samples collected at 2-d intervals. From these quarters, a total of 3,136 additional samples were evaluated. A total of 12 definitions (named A to L) based on combinations of the number of colonies isolated, whether or not the organism was recovered in pure or mixed culture, and the somatic cell count were evaluated for each organism (or group of organisms) with sufficient data. The sensitivity (ability of a definition to detect IMI) and the specificity (Sp; ability of a definition to correctly classify noninfected quarters) were both computed. For all species, except Staphylococcus aureus, the sensitivity of all definitions was