Dairy Science Commons^™

Strategic Nutritional Interventions With Probiotics And Their Relationship To Performance, Feeding Behavior, And Reticulorumen Environment In Cows And Calves Under Subacute Ruminal Acidosis Risk, Gustavo Mazon Correa Alves

Theses and Dissertations--Animal and Food Sciences

Subacute ruminal acidosis (SARA) is a digestive disorder in ruminants characterized by extended periods of low reticulorumen pH. This digestive disorder is commonly observed in ruminants fed diets with elevated proportions of non-fibrous carbohydrates. This disorder has been vastly studied in adult dairy cattle and has been associated with losses in milk production, changes in feeding behavior, damage to the gastrointestinal tract, and premature culling. Although vastly studied in adult cattle, there is limited research on the effects of SARA in calves. SARA might be prevented by modifying the reticulorumen environment with probiotic supplements containing lactateutilizing bacteria such as Megasphaera …

Utilizing Precision Technologies To Validate A Real-Time Location System For Dairy Cattle And Monitor Calf Behaviors During Heat Stress, Emily Rice

Theses and Dissertations--Animal and Food Sciences

With the increase in on-farm precision dairy technologies (PDT) utilization, large quantities of information are readily available to producers. A more recently available technology for use in livestock species is the real-time location system. These technologies offer dairy producers the opportunity to monitor and track real-time locations of cows, track locomotion patterns, and summarize specific area usage. However, the usefulness of these insights is heavily dependent on the performance of the technology. Therefore, the first objective of this dissertation was to assess the positioning recording performance and the usefulness of the data recorded of a real-time location system (Smartbow GmbH; …

Precision Livestock Farming And Personality As Tools To Understand Dairy Calf Individual Variation In Performance, Behavior, And Response To Stress, Megan Marie Woodrum Setser

Theses and Dissertations--Animal and Food Sciences

Individual differences impact animal responses to their environments and can be observed with animal personality (stable behavioral differences with populations) and food neophobia (avoidance of unfamiliar feeds). These individual differences can influence cattle performance and welfare. Precision technologies, such as automatic feeding systems (AFS) and accelerometers continuously measure feeding behaviors and activity and may allow us to relate individual differences to behaviors in the home environment. Therefore, the first objective was to determine if food neophobia was associated with feeding behaviors measured by AFS. Food neophobia was associated with rewarded visits to the AFS, but to no other feeding behaviors. …

Personality Traits Of Dairy Calves And Their Relationship With Feeding Behavior, Activity, And Performance, Emily A. Michalski

Theses and Dissertations--Animal and Food Sciences

Detection of individual differences in personality traits of animals may prove beneficial for producers to help tailor management for individuals and to make selection decisions. Therefore, the objectives of this thesis were to

1) review and evaluate literature on relationships between individual cattle personality traits and feeding behavior, activity, and performance; and

2) evaluate and develop tests suitable for characterizing crossbred dairy-beef calves’ personalities and associations with behavioral patterns and performance.

The existing literature indicates that growth, intake, activity, and milk production measures from precision technologies have associations with cattle personality traits and behaviors identifiable through standardized tests. This indicates …

Isolation Box Test (Ibt) And Dairy Calf Personality Traits Relationship With Performance Through Weaning, Megan Marie Woodrum Setser

Theses and Dissertations--Animal and Food Sciences

Personality tests are utilized to characterize individual differences in personality traits across species. Currently, there is no objective personality test that can be implemented on-farm to measure personality in dairy calves. Measuring personality of youngstock in the dairy industry may allow producers to utilize information on individual differences for management decisions and limit the investment in unfit individuals. The isolation box test is a personality test that has potential to be adapted and utilized for dairy calves. The main objective of this thesis is to develop, validate, and utilize an isolation box test for use on-farm in dairy calves. More …

The Economics Of Milk Quality Management Practices And Milk Pricing In Simulated United States Dairy Herds, Derek Thomas Nolan

Theses and Dissertations--Animal and Food Sciences

Mastitis is considered one of the most common and costly diseases in the dairy industry. Intramammary infection status at a herd level is measured using somatic cell count (SCC). Understanding the total cost of an elevated somatic cell count can help influence dairy farmers to lower SCC and select management practices to produce higher quality milk. The first objective of our research was to determine if the cost of an elevated somatic cell count to farms can be decreased through the adoption of management practices with varying expenses. Using stochastic simulation modeling, the adoption of three differently priced management practices …

Microbial Interactions Between Compost Bedded Pack Barn Bedding And Teat Exposure In Transition Dairy Cattle, Tanya Lynn France

Theses and Dissertations--Animal and Food Sciences

Compost bedded pack barns utilize composting methods which provide a soft surface for dairy cows to lie on. This requires optimal microbial growth, which may increase the exposure of mastitis-causing pathogens to the teats of early lactation animals. Bedding characteristics, bedding bacteria, and bacterial counts on the teat skin, teat ends, and in the milk of early lactation dairy cows housed on a compost bedded pack were assessed over a 6-month time. The main objective was to determine the relationship between environmental effects (bedding characteristics and weather conditions) and cow-level (teat skin, teat end, milk) bacteria counts over time in …

Effects Of Yeast-Derived Microbial Protein On Transition Dairy Cow Health And Performance, Gustavo Mazon Correa Alves

Theses and Dissertations--Animal and Food Sciences

The transition period for dairy cows is defined as the three weeks pre and postpartum. During the transition period, dairy cows experience a myriad of metabolic, managerial, and nutritional requirement changes. These changes lead to stress and increased susceptibility to diseases which can negatively affect lactational performance in the short and long term. However, dietary amino acid availability can have a dramatic impact on the health and performance of dairy cows around parturition. Thus, the objective of the thesis was to evaluate the effects of supplementing yeast-derived microbial protein, as an alternative protein source for dairy cows during the transition …

Evaluating Costs Associated With Management Decisions Of Replacement Dairy Heifers And Their Impact On The Total Rearing Investment, Anna Catherine Hawkins

Theses and Dissertations--Animal and Food Sciences

Replacement heifer rearing is critical for the future of the dairy operation, especially to improve genetic merit and maintain herd size. A replacement heifer from the day she is born to the day she calves herself is generally a 2-year investment without potential income. A myriad of options exists on how to manage, fed, and ultimately raise replacement heifers. This study quantifies the costs associated with replacement heifer management decisions from birth to calving related to housing, labor, feed and health. The heifer rearing period can be broken into pre and post weaning sections to allow for more understanding the …

Automated Body Condition Scoring: Progression Across Lactation And Its Association With Disease And Reproduction In Dairy Cattle, Carissa Marie Truman

Theses and Dissertations--Animal and Food Sciences

Body condition scoring is a technique used to noninvasively assess fat reserves. It provides an objective estimate to describe the current and past nutritional status of the dairy cow and has been associated with increased disease risk and breeding success. Traditionally body condition scores are taken manually by visual appraisal on a 1 to 5 scale, in one-quarter increments. However, recent studies have shown the potential of automating the body condition scoring of cows using images. The first objective was to estimate the likelihood of disease development and breeding success, using odds ratios, associated with body condition score scored automatically …

Validation Of An Automated Behavior Monitoring Collar, And Evaluation Of Heat Stress On Lactating Dairy Cow Behavior With Access To A Free Choice Soaker, Lori Nicole Grinter

Theses and Dissertations--Animal and Food Sciences

Precision dairy technologies (PDT) are becoming more accessible and are therefore becoming more common on commercial dairy farms and in dairy research. Prior to any use of PDT, one should understand the precision, accuracy and bias of the device by a validations studies before interpreting the behavior measurements. Thus, the objective of the first section of my thesis is to validate ruminating, feeding and resting measurements of a behavior monitoring collar used in the second section. Precision dairy technology is used in heat stress studies to compare behavior of cows exposed to different heat stress treatments or abatement strategies. Heat …

On-Farm Utilization Of Precision Dairy Monitoring: Usefulness, Accuracy, And Affordability, Elizabeth A. Eckelkamp

Theses and Dissertations--Animal and Food Sciences

Precision dairy monitoring is used to supplement or replace human observation of dairy cattle. This study examined the value dairy producers placed on disease alerts generated from a precision dairy monitoring technology. A secondary objective was calculating the accuracy of technology-generated disease alerts compared against observed disease events. A final objective was determining the economic viability of investing in a precision dairy monitoring technology for detecting estrus and diseases.

A year-long observational study was conducted on four Kentucky dairy farms. All lactating dairy cows were equipped with a neck and leg tri-axial accelerometer. Technologies measured eating time, lying time, standing …

Dairy Cattle Hoof Disease Costs And Considerations For Prevention, Karmella A. Dolecheck

Theses and Dissertations--Animal and Food Sciences

Lameness is considered one of the most important health and welfare issues in the dairy industry. Understanding the total cost per case of disease-specific lameness can help producers select better treatment, prevention, and control strategies for their herds. The first objective of our research was to calculate the costs associated with 3 lameness causing hoof diseases: digital dermatitis, sole ulcer, and white line disease. To accomplish this, a survey of hoof health professionals (hoof trimmers and veterinarians) was conducted to identify treatment related expenditures per case. Data from the hoof trimmer responses to the survey and previously published research were …

An Evaluation Of Physiological And Behavioral Indicators Of Postpartum Diseases And Heat Stress In Dairy Cows, Amanda Renee Lee

Theses and Dissertations--Animal and Food Sciences

Precision dairy monitoring technologies can be used to monitor changes in physiology and behavior associated with transition period postpartum diseases and heat stress. Research Objective One was to evaluate how traditional visual examination, body condition, and locomotion with and without blood, milk, and urine variables and precision dairy monitoring technologies determine variable association with hyperketonemia, metritis, mastitis, hypocalcemia and retained placenta,. This was accomplished by monitoring cows 2 weeks before calving to 3 weeks after calving for any postpartum diseases using daily visual examination and automatically detected variables including activity, milk yield, milk components, lying behavior, feeding behavior, rumination time, …

The Effects Of Housing On Dairy Cow Comfort, Immune Function, Stress, Productivity, And Milk Quality, Matthew Richard Borchers

Theses and Dissertations--Animal and Food Sciences

Mastitis and milk quality affect every dairy farmer across the globe. Sand bedded freestalls are the industry standard for cow comfort, welfare, and the control of environmental mastitis. Compost bedded packs may be a viable alternative to the sand bedded freestall.

Compost bedded packs are maintained at a consistent level of moisture, nutrients, and aeration to favor compost microorganisms. Greater bacteria counts in bedding have traditionally been associated with increased mastitis rates and mastitis pathogens can be found in the pack and on the teats of cattle housed in even well managed compost bedded pack barns. In spite of this, …

Comparing Dairy Farm Performance And Heat Stress Abatment Strategies In The United States Using Summer To Winter Ratios, Jenna M. Guinn

Theses and Dissertations--Animal and Food Sciences

Heat stress abatement is a challenge for producers in the United States, especially in the southern states. Dairy producers could benefit by having a simply metric to measure heat stress abatement strategies with the goal of motivating improvement in heat stress management. Managing heat stress is key to ameliorating the effects on dairy cow performance. A study was performed to explore the use of a heat stress metric called the Summer to Winter performance ratio (S:W ratio), to quantify and compare farm performance variables among regions of the United States. Summer to Winter ratios were closest to 1.0 in the …

Differences In Behavioral And Physiological Variables Measured With Precision Dairy Monitoring Technologies Associated With Postpartum Diseases, I Ching Tsai

Theses and Dissertations--Animal and Food Sciences

The transition period is defined as the three weeks before and three weeks after the cow calves. Transition cow diseases are considered production diseases. Precision dairy monitoring (PDM) technologies measure physiological, behavioral, and production indicators on individual animals to improve management strategies and farm performance. The objective of the first study was to assess how hypocalcemia, hyperketonemia, and metritis affected variables measured by PDM technologies. The objective of the second study was to use variables from multiple commercially available PDM to examine alert performance generated from different analyses.

An Examination Of Milk Quality Effects On Milk Yield And Dairy Production Economics In The Southeastern United States, Derek T. Nolan

Theses and Dissertations--Animal and Food Sciences

Mastitis is one of the most costly diseases to dairy producers around the world with milk yield loss being the biggest contributor to economic losses. The objective of first study of this thesis was to determine the impacts of high somatic cell counts on milk yield loss. To accomplish this, over one million cow data records were collected from Southeastern US dairy herds. The objective of the second study was to determine optimum treatment cost of clinical mastitis by combining two economic modeling approaches used in animal health economics. The last objective of this thesis was to determine how much …

Precision Dairy Farming Technology Solutions For Detecting Dairy Cow Disease To Improve Dairy Cow Well-Being, Amanda Stone

Theses and Dissertations--Animal and Food Sciences

Dairy cow health is multifactorial and complex. High producing dairy cows have been described as metabolic athletes, but metabolic and infectious diseases around calving affect many cows. These diseases have drastic negative effects on dairy cow well-being, milk production, and dairy farm economics. Early disease detection could potentially improve disease management, treatment, and future prevention techniques. The first objective of this research was to evaluate the use of activity, lying behavior, reticulorumen temperature, and rumination time determined by precision dairy farming technologies to detect transition cow diseases including hypocalcemia, ketosis, and metritis. The second objective was to evaluate the ability …

Behavioral Gait Change Characterization And Detection Using Precision Dairy Monitoring Technologies, Barbara Wadsworth Jones

Theses and Dissertations--Animal and Food Sciences

Lameness is a painful disorder that decreases performance and is highly recognized as one of the most important health and welfare concerns for dairy cattle. Visual gait scoring is the most common way to detect gait change in dairy cattle. However, this is not only subjective, but is also time consuming and costly. A need to remove the subjective assessment of human observation exists. Therefore, automatic gait change detection for continuous monitoring by precision dairy monitoring technologies may be beneficial. The first objective of this research was to characterize behavior and production variables as cow gait changed to evaluate potential …

Assessment Of The Technical And Economic Potential Of Automated Estrus Detection Technologies For Dairy Cattle, Karmella Ann Dolecheck

Theses and Dissertations--Animal and Food Sciences

Poor estrus detection can limit the reproductive performance of a dairy herd. One objective of this research was to evaluate an alternative method to traditional estrus detection in the form of automated monitoring technologies. To accomplish this, the first study considered the ability of automatically monitored parameters (activity, number of steps, lying bouts, lying time, feeding time, rumination time, and temperature) to detect estrus. A second study compared automated activity monitoring to timed artificial insemination as reproductive management strategies on commercial herds. The other objective of this research was to evaluate the economic potential of automated estrus detection technologies. This …

An Evaluation Of Precision Dairy Farming Technology Adoption, Perception, Effectiveness, And Use, Matthew Richard Borchers

Theses and Dissertations--Animal and Food Sciences

Precision dairy farming technologies provide a variety of functions to dairy farmers. Little is known about dairy producer perception of these technologies. A study was performed to understand dairy producer perception of parameters monitored by precision dairy farming technologies. Calving has potential to be predicted using these same parameters and technologies. A second study was performed using two commercially marketed technologies in calving prediction. In order for these technologies to generate accurate and useful information for dairy farm use, they must accurately quantify these parameters. The final study evaluated the accuracy of five commercially marketed technologies in monitoring feeding, rumination, …

Algae Or Yeast Supplementation For Lactating Dairy Cows, Maegan E. Weatherly

Theses and Dissertations--Animal and Food Sciences

The objective of the first study was to quantify the effects of feeding Schizochytrium sp. microalgae (SP-1, Alltech, Inc., Nicholasville, KY) on milk fat and DHA content. Eight cows were fed: 0, 100, 300, or 600 g of algae per day. Fat percentage was greater (P < 0.05) for cows on treatments 0 g and 100 g than for cows on treatments 300 g and 600 g (P < 0.05). Docosahexaenoic acid in milk was greater for cows on treatment 300 and 600 than for cows on treatment 0 and 100 (P < 0.05).

The objective of the second study was to assess yeast supplementation effects on high and low forage dairy cow diets. Four cows were assigned to 1 of 4 treatments: 1) low forage (LF), 2) low forage with 10 g/d yeast (Yea-Sacc®; Alltech Inc., Nicholasville, KY; LFY), 3) high …

Assessing The Efficacy Of Automated Detection Of Estrus In Dairy Cattle, Lauren M. Mayo

Theses and Dissertations--Animal and Food Sciences

The detection of estrus continues to be a primary factor contributing to poor reproductive performance in modern dairy cattle. The objectives of this research were 1) to evaluate performance of automated detection of estrus using a reference standard of ovulation detection with temporal progesterone patterns 2) to evaluate the efficacy of parameters measured by automated detection of estrus systems 3) to evaluate the efficacy of alerts generated by several commercially available systems used for automated detection of estrus and 4) to determine the differences in these parameters among cows with or without poor health conditions at the time of estrus. …

The Impact Of Dual Chamber Cow Waterbeds As A Freestall Base, Barbara Alice Wadsworth

Theses and Dissertations--Animal and Food Sciences

The objectives of this research were to compare lying time, milk yield, rumination time, hock score, stall cleanliness, and stall temperature for 97 cows (Holsteins (n = 71), Jerseys (n = 10), and crossbreds (n = 16)) housed on Dual Chamber Cow Waterbeds™ (DCCW, Advanced Comfort Technology, Reedsburg, WI) or conventional rubber mattresses (MAT). This study was conducted at the University of Kentucky Coldstream Research Dairy Farm from January 18, 2012 to May 3, 2013. Lying times were longer (P < 0.01) for cows housed on the DCCW (10:32 ± 0:13) compared to cows housed on the MAT (9:47 ± 0:15). Milk yield was not different (P ≥ 0.05) between cows housed on the DCCW or MAT. Rumination times were greater (P = 0.03) for cows housed on MAT (6:44 ± 0:08) compared to cows housed on DCCW (6:29 ± 0:08). Hock scores were lesser (P = 0.02) for cows housed on DCCW (1.86 ± 0.03) compared to cows housed on MAT (1.97 ± 0.04). Stall cleanliness was not different (P ≥ 0.05) between the DCCW and the MAT. The DCCW stall temperature was warmer (P < 0.01) (13.29 ± 0.21 ⁰C) than the MAT (10.52 ± 0.21 ⁰C).

Compost Bedded Pack Barns For Dairy Cattle: Bedding Performance And Mastitis As Compared To Sand Freestalls, Elizabeth A. Eckelkamp

Theses and Dissertations--Animal and Food Sciences

Lameness and mastitis are the two most costly diseases in the dairy industry. Reduction of these diseases through housing and management is beneficial. Compost bedded pack (CBP) and sand freestall barns were compared in a long-term, on-farm study to assess the effect of housing on each disease. Another research objective was to evaluate the effects of ambient weather conditions on moisture and 20 cm internal temperature of CBP. Compost bedded pack moisture, C:N ratio, and internal temperature effects on cleanliness, mastitis, and bedding bacterial counts were also considered. The last research objective was to evaluate the economics of bedding material …

Compost Bedded Pack Barns: Management Practices And Economic Implications, Randi Alyson Black

Theses and Dissertations--Animal and Food Sciences

Compost bedded pack (CBP) barn design and pack maintenance procedures vary considerably, making advising and problem-solving challenging. One objective of this research was to characterize herd performance and management practices employed by Kentucky CBP managers (42 farms and 47 CBP facilities). Producer satisfaction, changes in historical bulk-tank somatic cell count, and improvement in herd performance parameters after transitioning to a CBP barn support reported CBP barn system benefits. Daily milk production increased from before moving into the CBP barn to the second year after (29.3 ± 0.3 vs. 30.7 ± 0.3 kg, respectively; P < 0.05) for farms using the CBP barn as the primary housing facility (n = 8). Increasing stirring frequency, stirring depth, and ambient temperatures increased pack temperature. Increased drying rate decreased CBP moisture. Increased 20.3 cm depth CBP temperature and ambient temperatures improved cow hygiene. Mastitis-causing bacteria thrive in conditions similar to optimal composting bacteria conditions, making reduction of these bacteria difficult in an active composting environment. Producers must pay attention to other management areas where preventive measures can be employed. The New Dairy Housing Investment Analysis Dashboard provides users an interactive and flexible decision tool to make more informed facility investment decisions.

Estimating The Economic Losses From Diseases And Extended Days Open With A Farm-Level Stochastic Model, Di Liang

Theses and Dissertations--Animal and Food Sciences

This thesis improved a farm-level stochastic model with Monte Carlo simulation to estimate the impact of health performance and market conditions on dairy farm economics. The main objective of this model was to estimate the costs of seven common clinical dairy diseases (mastitis, lameness, metritis, retained placenta, left displaced abomasum, ketosis, and milk fever) in the U.S. An online survey was conducted to estimate veterinary fees, treatment costs, and producer labor data. The total disease costs were higher in multiparous cows than in primiparous cows. Left displaced abomasum had the greatest costs in all parities ($404.74 in primiparous cows and …

Management And Technology Solutions For Improving Milk Quality, Amanda E. Sterrett

Theses and Dissertations--Animal and Food Sciences

Mastitis is one of the most common and expensive dairy cattle diseases. Mastitis prevention and management are key factors in herd health and improved milk quality. One objective of this research was to evaluate management solutions to maintain a low somatic cell count, based on survey responses from Kentucky dairy producers. Because hyperkeratosis may increase mastitis incidence, another objective of this research was to examine changes in teat end hyperkeratosis in a herd transitioning from a standard pulsation milking system to an individual quarter pulsation milking system. The last objective of this research was to evaluate technologies that monitored rumination …

The Effects Of Slow Release Urea On Nitrogen Metabolism In Cattle, Vaughn B. Holder

Theses and Dissertations--Animal and Food Sciences

The objective of this research was to investigate the effects of slow release urea on N metabolism in cattle. The ruminal behavior of Optigen®II and the effect of basal diet on the in situ degradability of urea and Optigen®II were evaluated. The effect of slow release urea and its interaction with degradable intake protein (DIP) level in the diet on N retention and excretion was evaluated utilizing 8 Holstein steers in a 4 x 4 Latin square experiment. In addition, the effect of slow release urea and DIP level on ruminal and systemic urea kinetics was evaluated using stable isotope …