Two lactation trials were used to investigate corn grazing as a management tool for dairies. Control (n = 18) cows, housed in free-stall barns were allowed ad libitum access to TMR while Grazing (n = 18 to 36) cows were limited TMR down to 70% of that in Controls and allowed 24-h access to corn plots. By wk 3, Grazing cows consumed 7.9 +/- 1.5 kg/hd/d of standing corn. By wk 7, the crop had matured and Grazing cows consumed 11.42 kg/hd/d of corn grain. Intake of TMR by Controls was 20.07 +/- 0.46 kg DM/hd/d, 19.78% greater than Grazing groups. Corn grazing had no impact on body weight, condition score, or ruminal pH, but significantly increased milk production in the Grazing group. Corn grazing reduced the need for purchased commodities, while improving milk production and performance. The value of saved commodities and increased milk production was $0.71 per cow/d.

<p>The objective of this study was to evaluate the long-term effects that early life events have on heifer growth up to 400 d of age, heifer conception rate, survivability through first lactation, and first lactation milk production of calves raised in automatic calf feeders. Chapter one evaluates possible early life variables that would affect heifer growth and lifetime production as well as research that has been done to predict future growth. The major points discussed include pre-weaning feeding strategies, automatic calf feeding systems, respiratory disease and ways to diagnose cattle with this disease, and the impact of early life growth on the future productivity of the dairy cow.<br></p> <p>The second chapter discusses in detail the process of creating a predictive equation using significant early life variables that affect Holstein heifer growth up to 400 d of age. Variables collected for the growth analysis included sixty d cumulative milk consumption (MC), serum total protein values, respiratory disease and scours incidences, genetic body size, birthweights, and incremental body weight variables on a commercial dairy farm from October 1, 2015 to January 1, 2019. Calves were fed pasteurized whole milk through an automated calf feeding system (feeders = 8) for 60 d (range: 48 – 126d), with a 30% Crude Protein (CP) and 5% Crude Fat enhancer added at 20 g/L of milk. Calves were weighed at birth and several other times prior to calving. Average birth weight of calves was 40.6 ± 4.9 kg (mean ± SD), serum total protein was 6.7 ± 0.63 g/dL, and cumulative 60 d MC was 508.1 ± 67.3 L with a range of 179.9 to 785.1 L. Daily body weights were predicted for individual animals using a third order orthogonal polynomial to model growth curves. The linear and quadratic effects of cumulative 60 d milk consumption, birthweight, feeder, yr born, season born, respiratory incidence, and genetic body size score were significant (<i>P</i><0.0001) when predicting heifer body weight at 400 d (pBW₄₀₀) of age (R²=0.31). There was up to a 263 kg difference in pBW₄₀₀between the heaviest and lightest animal. Birthweight had a significant effect on predicted weights up to 400 d (<i>P</i><0.0001), and for every 1 kg increase in birthweight, there was a 2.5 kg increase in pBW₄₀₀. The quadratic effect of cumulative 60 d MC was significant for pBW₄₀₀ (<i>P</i><0.0001). When 60 d MC was divided into quartiles, heifers had the highest pBW₄₀₀in the third quartile, when 60 d MC was between 507.8 and 552.5 L. Body size composite (genomic index) showed a 21.5 kg difference in pBW₄₀₀ between the top and bottom 25^th percentile of heifers. Heifers were 4.2 kg lighter at 400 d if treated for respiratory disease 3+ times during the first 60 d of life, compared to heifers not treated for respiratory disease.</p> <p>The third chapter utilizes the data described in chapter two and followed those heifers through breeding and first lactation. Heifer conception age and 280 d first lactation milk production (280M) were collected. Average age at conception was 437.5 ± 45.0 d; range of 308 to 631 d (n=5,193), and average 280M was 9,305 ± 1,371.8 kg; range of 712-13,358 kg (n=1,324). Heifer conception age was impacted by season, yr, and the quadratic effects of predicted bodyweight at 300 d of age (pBW₃₀₀) and ADG (0-400; all <i>P</i> < 0.05; total model R² = 0.08). Season born, ADG (0 - 400 d), genomic milk, and the linear effect of heifer conception age had a significant impact on 280M (all <i>P</i> < 0.05; R² = 0.28). For every 1 kg increase in genomic milk value there is 1.42 kg increase in first lactation 280M. Calves not diagnosed with bovine respiratory disease (BRD) from 60-120 d old had a significantly higher chance for survival to first lactation than animals treated three or more times for BRD (hazard ratio = 0.71, 95% CI = 0.574 to 0.886, <i>P </i>= 0.0023, Table 3.3). Heifers treated twice or more for BRD had reduced likelihood to become pregnant than heifers not treated for BRD from 60-120 d (twice <i>P </i>= 0.02; three or more <i>P </i>= 0.05). </p> <p>In conclusion, the results from this thesis support that early life events in Holstein heifers continue to influence future growth and productivity. Future research aims to validate the predictive equation generated in chapter two on farm as well as adapt the equation to other farms allowing them to utilize it as well. The goal is to have farms utilize this tool to aid in their replacement heifer management decisions and to select the most productive heifers for the future of their herds. </p>

According to the USDA Economic Research service, farm-level prices are on the decline. This decline in prices particularly hurts smaller scale operators with many needing to rely on off-farm income in order to ensure they remain in operation. This thesis studies two problems of key interest to the Southeast region and the State of Kentucky by investigating dairy management practices and the environmental benefits of hemp production. As dairy prices have been on the decline and dairy co-ops have tightened their restrictions on somatic cell count (SCC) levels, dairy farmers and farm managers must decide the best course of action for maintaining milk quality in order to maintain their contract and profitability. Maintenance decisions as well as factors like sanitation and animal living conditions can all contribute to bulk tank SCC and depending on the type of incentives or penalties instituted by the co-op they can have an impact on net farm income. The objective of the dairy study is to determine which dairy management practices have the largest impact on SCC levels. Industrial hemp is produced worldwide. Historically, the major producers of hemp have been China, Europe, and Russia. In 2014, the passage of the Farm Bill opened the door to the production of Industrial hemp through the development of state pilot programs. Then the 2018 Farm Bill removed industrial hemp from the Scheduled Drug list. This has further expanded the opportunities and excitement for this crop. The plant’s versatility and the variety of products that can be made from it are coming to light. Sustainability is one of the key attributes touted concerning industrial hemp. Specifically, in the state of Kentucky, it is expected to be a replacement for tobacco and other traditional crops. However, how does the crop compare to tobacco production in terms of sustainability? The objective of the hemp study is to develop a life cycle analysis on the planting and harvesting of hemp and compare its impacts to more traditional crops.

<p dir="ltr">Consistent intake and feeding behavior records collected on a per-cow basis are useful measures for optimization of feed efficiency, production, and ultimately, resource and economic sustainability of dairy operations. However, current methods for collection are often labor-intensive and impractical to maintain for both individual- and group-housed cows. Across the dairy industry, total mixed rations (TMR) are fed to promote balanced nutrient intake and satisfy evolving energy requirements. TMR intake is an extensively investigated phenotype of dairy cattle and is known to be highly variable due to both intrinsic and extrinsic determinants, which can include composition and palatability of offered TMR, intensity of environmental stressors, and biological aspects of the individual animal. Reductions in TMR intake negatively impact health and production; thus, industry demand has heightened for precise intake monitoring systems. Cyber-physical systems that employ cameras as a sensing device are proposed solutions to ambiguity in existing feeding strategies. Prior studies have demonstrated the efficacy of camera systems to monitor other phenotypes of dairy cattle including body condition, locomotion and gait, social interaction, and early detection of negative health events. In this study, an OAK-D PoE stereo vision camera system was employed to estimate volume of TMR and monitor feeding behavior in a dynamic barn environment. The system leveraged open-source Python software to measure relative depth in near real time and autonomously estimate the amount of TMR present in a feed bunk. Image data were processed to generate a point cloud for which volume of TMR was estimated at a rate of approximately 50 estimates/min. Two experiments were conducted in which mass, volume, and density of TMR, as well as feeding behavior (exclusive to Exp. 2) were manually recorded to be compared to volume estimates of TMR output by the camera system. In Exp. 1, diet type (high-density vs. low-density; HD and LD, respectively), lighting (10,000 Lm vs. existing barn lighting; on vs. off, respectively), and shape of offered TMR (undisturbed vs. simulated post-meal bout; no divot vs. divot, respectively) were assessed for impact on system accuracy across five intervals of known TMR volume. In Exp. 2, system volume estimates were evaluated over time when a cow was present and exhibiting normal feeding behavior. The system accurately estimated volume of TMR across evaluated conditions in Exp. 1, despite significance of the divot condition. As TMR disappeared over time in Exp. 2, system volume estimates decreased with a similar pattern. When the cow was removed and measured TMR volume was unchanged at 2 h collection timepoints in Exp. 2, system volume estimates also remained unchanged and consistent. Post-collection of replicates in Exp. 2, frequency and duration of meal bout events were estimated based on differences in volume when cows were eating. Estimated frequency and durations were similar to manually recorded data and indicated feasibility of behavioral monitoring as an opportunity for further system development. Prior studies have integrated machine learning approaches for refinement of camera monitoring systems and mitigation of reported environmental impact on accurate quantification of TMR volume. Further development of the current system through integration of machine learning applications will improve accuracy and industry applicability as an automated feed bunk management tool for collection of TMR intake and behavioral data on a per-cow basis.</p>

Nowadays those who live or work in the countryside have increasingly access to technologies that favor the development of their daily activities. Smartphones and tablets with android operating systems, which are every day more accessible to the farmers, offer opportunities for the use of applications that support them in decisionmaking. These new tools are available to the rural man, rural extension and/or technical assistance professionals, and can be used to increase the competitiveness of their properties. This study aimed to assess the C7 Milk II application to find out its strengths and weaknesses, as well as to contribute to the provision of a free management system, which is efficient and easy for the farmers and technicians to use, positively influencing the management of dairy farming properties. Thus we tested the use of this application in two family farms: one in the city of Alto Alegre/RS and another in the city of Espumoso/RS. We accompanied the development of the activities related to the tool use, and recorded the farmers´ perceptions on it. We also used contacts and questionnaires to find out the perception of field technicians who work in the region in order to identify the potential and limitations of the use of the applications among the rural men. At the end of the study, we found out that the application has potential as a tool to give greater precision to the dairy management, since it has several strengths. However, it also has some weaknesses, which need to be improved to have greater acceptance by farmers and technicians. Among the limitations of the application use, there are some difficulties for the farmers to adopt a notes routine about the activity, as well as their lack of ability to work with new technologies. These aspects impair their use in a big scale as a complementary tool in the management of dairy farming. The agility and the mobility of the tool; the generating of information for decision-making with low cost access and application service; and the farmer´s thinking on his activity have being considered potential factors. / Atualmente quem mora ou trabalha na zona rural tem cada vez mais acesso a tecnologias que favorecem o desenvolvimento das atividades. Os aparelhos smartphones e tablets com sistema operacional android, cada dia mais acessíveis ao homem do campo, oferecem oportunidades para utilização de aplicativos que auxiliam o produtor (a) rural na tomada de decisões. Estas novas ferramentas disponíveis ao homem do campo, profissionais da extensão rural e/ou assistência técnica podem ser utilizadas para aumentar a competitividade dessas propriedades. Este trabalho buscou avaliar o aplicativo C7 Leite II, seus pontos fortes e a melhorar, com isso, contribuir para a disponibilização de um sistema gerencial gratuito, eficiente e de fácil utilização por parte de produtores e técnicos, influenciando positivamente no gerenciamento de propriedades rurais que trabalham na atividade leiteira. Para esta avaliação foi testado a utilização do aplicativo em duas propriedades rurais da agricultura familiar, uma no município de Alto Alegre/RS e outra em Espumoso/RS, sendo acompanhado o desenvolvimento das atividades de utilização da ferramenta e registro das percepções dos produtores. Também foi levantado através de contatos e aplicação de questionários, a percepção de técnicos de campo que atuam na região de estudo, tentando identificar os potenciais e os limitantes da utilização de aplicativos junto ao seu público assistido. Ao final verificou-se que o aplicativo tem potencial como ferramenta para dar maior precisão no gerenciamento leiteiro, por apresentar vários pontos fortes, mas também precisa melhorar em outros pontos para que tenha maior aceitação pelos produtores e técnicos. Entre os limitantes do uso do aplicativo, aparecem com maior força as dificuldades dos produtores adotarem uma rotina de anotações sobre a atividade, e a falta de habilidade em trabalhar com as novas tecnologias, aspectos que comprometem até certo ponto o uso em maior escala de aplicativos como ferramenta complementar no gerenciamento da atividade leiteira. Já como potenciais aparecem a agilidade e mobilidade da ferramenta, geração de informações para tomada de decisão com baixo custo de acesso e manutenção do aplicativo, e a reflexão gerada no produtor (a) sobre como vem conduzindo sua atividade.

The purpose of this study is to evaluate the value of systematic thoracic ultrasonography (TUS) for detecting bovine respiratory disease (BRD) related lung damage in Holstein x Angus crossbred calves. Because the dairy industry is known to operate on small profit margins, it is important to assess the potential of this technology to help prevent the main source of financial loss related to calf production that dairy producers face. Studies have shown that BRD may impact nearly a fourth of all dairy calves before weaning. In an industry that is currently growing and evolving, it is important that producers have all the necessary resources to operate efficiently. TUS is known to be a quick and accurate predictor of BRD related lung damage, but this study focuses on the financial implications of BRD related lung damage on calf growth and efficiency—average daily gain (ADG) and milk-to-gain (M:G)—and the value of implementing TUS information to make sound management decisions. TUS along with BRD diagnosis information give producers a unique perspective on future growth and development of calves and could be part of the solution to promote larger profit margins for dairy producers. We find that the value associated with TUS and BRD diagnosis information is between $0.88/head and $13.44/head and depends on BRD incidence rate, feed price, and feeder price. Depending on the cost to the farm, it may be beneficial to implement this as a way to manage BRD damage, which we know to influence calf growth and efficiency.