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Title: Milk production and related factor response of dairy herds after enrollment on a production testing program
Creator: Schramski, Edward Alfred
Date: 1969
Collection: Electronic Theses & Dissertations

Title: Variables affecting ration factors for estimating 305-day production from part lactations
Creator: Lamb, Robert C.
Date: 1959
Collection: Electronic Theses & Dissertations

Title: Effects of dietary factors and rumen pH on rumen biohydrogenation pathways and risk of milk fat depression
Creator: Sun, Yan (Graduate of Michigan State University)
Date: 2016
Collection: Electronic Theses & Dissertations
Description: "Yield of milk components continues to be the principal driver of variation in producer milk payments. Therefore, diet-induced milk fat depression negatively impacts financial income of dairy farmers. Our overall objective is to determine the effects of dietary factors and rumen pH and their interactions on biohydrogenation pathways and the formation of biohydrogenation intermediates (e.g. t10, c12 conjugated linoleic acid, [CLA]) that limit fat synthesis in the mammary gland. By using an in...
Show more"Yield of milk components continues to be the principal driver of variation in producer milk payments. Therefore, diet-induced milk fat depression negatively impacts financial income of dairy farmers. Our overall objective is to determine the effects of dietary factors and rumen pH and their interactions on biohydrogenation pathways and the formation of biohydrogenation intermediates (e.g. t10, c12 conjugated linoleic acid, [CLA]) that limit fat synthesis in the mammary gland. By using an in vitro batch culture system in the first three experiments, we determined the effects of common dietary factors (dietary unsaturated fatty acid concentration, starch content and starch fermentability, and Saccharomyces cerevisiae fermentation product) and culture pH on biohydrogenation pathways, as well as their interactions. In all three experiments, culture pH had the greatest influence on biohydrogenation pathways, with low culture pH increasing the formation of t10, c12 CLA in vitro. In the first experiment, low culture pH and increasing concentration of corn oil increased the formation of t10, c12 CLA. Increasing corn oil concentration at low culture pH increased t10, c12 CLA concentration. In the second experiment, low culture pH, combined with highly fermentable starch (high moisture corn), increased t10, c12 CLA concentration. Although starch fermentability did not affect t10, c12 CLA overall, high starch content provided by high moisture corn increased t10, c12 CLA concentration at low culture pH. In the third experiment, highly fermentable starch (high moisture corn) at low culture pH increased t10, c12 CLA concentration. Rumen fluid collected from cows supplemented with Saccharomyces cerevisiae fermentation product decreased t10, c12 CLA concentration, especially when combined with high moisture corn at low culture pH. The fourth experiment was an in vivo study, which determined the effect of production level on severity of diet-induced milk fat depression and biohydrogenation pathways for mid- and late lactation cows. A milk fat depression-inducing diet decreased milk fat content and fat yield, and increased t10, c12 CLA concentration in milk. Higher producing cows were at higher risk for diet-induced milk fat depression, exhibiting greater reductions in milk fat content and yield and a greater increase in milk t10, c12 CLA concentration than lower producing cows. Cows fed a milk fat depression-inducing diet had a lower mean rumen pH and greater rumen pool of t10, c12 CLA than cows fed a control diet. Dietary factors interacted with rumen pH to influence biohydrogenation pathways and t10, c12 CLA concentration, and production level also impacted cow response to diet-induced milk fat depression. Further work is required to clarify interactions between dietary factors and rumen pH and their effects on rumen bacterial populations. Mechanisms behind the interaction between production level and diet induced-milk fat depression are still unclear and should be examined."--Pages ii-iii.
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Title: The relationship between A.I. sires and the index value of their dams
Creator: Everett, R. W. (Robert Wesley)
Date: 1963
Collection: Electronic Theses & Dissertations

Title: A genetic study of milk yield of native breeds of cattle and crosses with Brown Swiss in India
Creator: Ruvuna, Francis
Date: 1980
Collection: Electronic Theses & Dissertations

Title: Effects of stocking rate and supplementation on pasture utilization, cow performance, and rumen environment in a pasture-based and automatic milking system
Creator: Nieman, Christine
Date: 2012
Collection: Electronic Theses & Dissertations
Description: Integration of automatic milking systems (AMS) into Midwestern pasture-based systems has been suggested as an alternative low cost and labor efficient dairy system, but proper integration of this technology into a pasture-based dairy system is not well understood. The objective of this thesis was to determine management guidelines for a pasture-based AMS system by examining the combined effect of stocking rate and feeding strategies on cow performance, AMS use, feed degradation, dairy cattle...
Show moreIntegration of automatic milking systems (AMS) into Midwestern pasture-based systems has been suggested as an alternative low cost and labor efficient dairy system, but proper integration of this technology into a pasture-based dairy system is not well understood. The objective of this thesis was to determine management guidelines for a pasture-based AMS system by examining the combined effect of stocking rate and feeding strategies on cow performance, AMS use, feed degradation, dairy cattle genotype, and pasture utilization. An investigation lasting 8 weeks was conducted using a completely randomized design with a 2 x 2 factorial of two stocking rate systems ( high stocking rate (HSR 2.89 cows/ha); low stocking rate (LSR 1.92 cows/ha)) and two genotypes of Holstein cattle, United States Holstein (USH) and New Zealand Holstein Friesian (NZF). The HSR treatment received a partial mixed ration (PMR; 40% ground corn and 60% legume grass haylage) in variable amounts (average: 4.86 kg /cow; ± 0.14; mean and SEM) to supplement deficits in pasture growth rate and availability. Results indicated no differences in milk production or AMS use between treatments, although differences were found between genotypes. An in situ experiment showed no differences in feed degradation, suggesting that the rumen environment was not affected by PMR supplementation. No differences in pasture utilization or pasture growth were detected between the HSR and LSR treatments. The results of this thesis suggest that dynamic supplementation in the HSR treatment did not affect pasture utilization, cow performance, AMS use, or the rumen environment.
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Title: Mammary development in relation to plane of nutrition and serum hormone concentrations in pre- and postpubertal heifers
Creator: Sejrsen, Kristen
Date: 1981
Collection: Electronic Theses & Dissertations

Title: Regulation of bovine anterior pituitary hormones release and synthesis
Creator: Zolman, Josef, 1942-
Date: 1973
Collection: Electronic Theses & Dissertations

Title: Penicillin blood level studies in dairy cattle
Creator: Ferstl, H. T.
Date: 1949
Collection: Electronic Theses & Dissertations

Title: Variability factors and use of milk fat-protein concentration ratio in Michigan Holstein dairy cows
Creator: Raphael, William
Date: 2001
Collection: Electronic Theses & Dissertations

Title: Relations between weight at first calving and milk production during the first lactation
Creator: Miller, Robert H.
Date: 1958
Collection: Electronic Theses & Dissertations

Title: Isolation of salmonella and escherichia coli in feces of cull (market) dairy cows at slaughter
Creator: Akpinar, Özlem
Date: 2001
Collection: Electronic Theses & Dissertations

Title: Regulation of the ruminal environment by lactating dairy cows
Creator: Mooney, Charles Steven
Date: 2006
Collection: Electronic Theses & Dissertations

Title: Understanding how induced luteolysis in dairy cattle affect corpora lutea characteristics and fertility
Creator: Minela, Thaina
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Efficient manipulation of estrous cycle via exogenous treatments is critical for fertility in dairy cows following timed artificial insemination (TAI) programs. Luteolysis is a key event that warrants reproductive success in manipulated estrous cycles. The main objective of this thesis was to characterize luteolysis following different doses of cloprostenol sodium (CLO) and its effects on luteal blood flow (LBF) and fertility of lactating dairy cows. The first objective was to determine the...
Show moreEfficient manipulation of estrous cycle via exogenous treatments is critical for fertility in dairy cows following timed artificial insemination (TAI) programs. Luteolysis is a key event that warrants reproductive success in manipulated estrous cycles. The main objective of this thesis was to characterize luteolysis following different doses of cloprostenol sodium (CLO) and its effects on luteal blood flow (LBF) and fertility of lactating dairy cows. The first objective was to determine the effect of luteolytic and sub-luteolytic doses of CLO in dairy heifers with an early and mid-cycle corpus luteum (CL). Measurement of LBF was indicative of complete, and partial luteolysis following various doses of CLO. Heifers receiving multiple doses of CLO had complete disappearance of LBF 4 d post-treatment. The second objective was to assess the effects of different CLO dose strategies during TAI programs on pregnancy rates per AI (PR/AI) in lactating dairy cows. We also aimed to verify the association between LBF around TAI with PR/AI in cows that had a d 7 and 14 CL. Cows were treated with a single full dose, two full doses 24 h apart or a double dose of CLO. There was no evidence of differences in PR/AI between CLO doses. But, 3rd+ parity cows treated with a single full dose of CLO had greater pregnancy loss form d 24 to 34 post-AI. Treatment with double dose of CLO resulted in similar PR/AI independent on synchronization status. Amount of LBF at 2 and 4 d post-treatment was a predictor of PR/AI 34 d post-AI. Cows with decreased LBF of both d 7 and 14 CL below a median cutoff had greater PR/AI 24 d post-AI. Multiparous cows treated with double doses of CLO avoided lower fertility in non-synchronized cows and greater pregnancy losses compared to cows treated with a single full dose.
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Title: Predictive modeling for the early identification of cattle at risk for transition diseases
Creator: Wisnieski, Lauren
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "The transition period is defined as the time that spans approximately 3 weeks before to 3 weeks post-partum. During the transition period, dairy cattle experience tremendous physiological changes that occur to prepare for milk production. Cows that transition poorly undergo excessive metabolic stress, which increases the risk for disease. Metabolic stress is a physiological state composed of 3 components: inflammation, oxidative stress, and nutrient metabolism. Cows undergoing metabolic...
Show more"The transition period is defined as the time that spans approximately 3 weeks before to 3 weeks post-partum. During the transition period, dairy cattle experience tremendous physiological changes that occur to prepare for milk production. Cows that transition poorly undergo excessive metabolic stress, which increases the risk for disease. Metabolic stress is a physiological state composed of 3 components: inflammation, oxidative stress, and nutrient metabolism. Cows undergoing metabolic stress are typically identified by measuring biomarkers, monitoring feed intake, and reviewing health records. The biomarkers that are typically used to monitor metabolic stress are non-esterified fatty acids (NEFA) and beta-hydroxybutryrate (BHB), which are nutrient metabolism biomarkers. Although NEFA and BHB are effective for identifying cows undergoing metabolic stress, they are measured too close to calving to make proactive changes in management to reduce disease incidence in the current calving cohort. Therefore, our objective was to build predictive models for transition cow diseases using all 3 components of metabolic stress at dry-off, which would allow more time to intervene with proactive interventions. To address this objective, we designed a prospective cohort study carried out on 5 Michigan herds (N = 277 cows). We randomly selected cows to form 18 calving cohorts, which were defined as cows at the same stage of lactation that were expected to calve at approximately the same time. We followed the cows until 30 days post-partum to monitor for disease occurrence. Disease was defined as an aggregate outcome where a cow was defined as positive if she was diagnosed with 1) one or more clinical transition disease outcome (mastitis, metritis, retained placenta, ketosis, lameness, pneumonia, milk fever, displaced abomasum) and/or 2) one or more adverse health events (i.e. abortion, death of calf or cow). Our first specific aim was to build individual cow-level models, which are presented in Chapter 2. We built separate model sets for each component of metabolic stress, and a model set that included all 3 components. We hypothesized that the combined model would be better able to predict transition cow diseases. Our hypothesis was supported and the area under the curve calculated from receiver operator curve curve analyses was significantly higher for the combined model compared to the separate model sets (P < 0.05). Our second specific aim was to build cohort-level models, which we addressed in Chapters 3 and 4. In Chapter 3, we tested ways to aggregate individual-level biomarker and covariate data to the cohort-level. We tested 3 different methods that we referred to as the "central," "dispersion," and "count" methods. We also tested combining all 3 methods for prediction. We hypothesized that these methods would be effective at aggregating data to the cohort level. We found that the central method, which aggregated data either by calculating the mean (for continuous variables) or the median (for categorical variables) of values within a cohort, was the only method that produced viable models. Chapter 4 tested if individual level predictive probabilities generated from models in Chapter 2 can be aggregated to predict disease incidence at the cohort-level. We tested 3 different methods to aggregate predicted probabilities which we referred to as the "p-central," "p-dispersion," and "p-count" methods, and we tested the efficacy of combining all 3 methods. We hypothesized that the models would produce valid disease estimates. We found that the p-dispersion method was the only method that produced viable models, which involved calculating the standard deviation of predicted probabilities within a cohort."--Pages ii-iii.
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Title: Characterizing the health and welfare of periparturient dairy cows in a pasture-based automatic milking system
Creator: Elischer, Melissa Frances
Date: 2013
Collection: Electronic Theses & Dissertations
Description: The periparturient period, defined as three weeks prior to and three weeks after parturition, is a time of great physiological, environmental, and social stress for dairy cows. This transition into lactation is often marked by negative energy balance, oxidative stress, and impaired immune function. These factors combine to create the perfect storm to challenge a cow's homeorhesis. The periparturient period has been well characterized in cows in traditional dairies that are milked at a fixed...
Show moreThe periparturient period, defined as three weeks prior to and three weeks after parturition, is a time of great physiological, environmental, and social stress for dairy cows. This transition into lactation is often marked by negative energy balance, oxidative stress, and impaired immune function. These factors combine to create the perfect storm to challenge a cow's homeorhesis. The periparturient period has been well characterized in cows in traditional dairies that are milked at a fixed frequency in a parlor and fed a total mixed ration, however, little research on alternative milking and feeding systems exists. One such system is a combined pasture-based automatic milking system (AMS) dairy. This combination of milking system and diet is still relatively uncommon, however, there are many potential benefits for both cows and producers. Despite the growing interest in pastured-AMS dairies, there is little information available regarding how the periparturient cow is impacted by this milking system and diet. Therefore, the aim of this research was to use physiological, production, and behavioral data to evaluate the health and welfare of pastured multiparous and primiparous cows milked in an AMS during the periparturient period. Results indicate that multiparous and primiparous cows experience metabolic and oxidative stress and changes in pro-inflammatory cytokine expression, but that there is not a dramatic difference between parities or during the periparturient period. Non-invasive behavioral measures and production data support these results. Indeed, a well-managed pasture-based system combined with the correct implementation of AMS seems to offer benefits and does not negatively impact cows during the critical periparturient period.
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