Dairy Science Commons^™

Maturation And Culture Media Effects On In Vitro Bovine Embryo Developmental Competence, Ciara M. Helland

Master's Theses

In vitro produced bovine embryos are critical to the cattle industry. However, these embryos have altered morphology, epigenetics, and metabolism when compared to their in vivo counterparts. The aim of this thesis was to alter maturation and culture media to improve the developmental competence of in vitro bovine embryos. This thesis is comprised of three experiments and one proof of concept study. Each experiment followed the same general layout: oocyte aspiration from Jersey or Holstein ovaries, oocyte maturation for 24 hours, fertilization with bull semen for 24 hours, then embryo culture for 7-8 days in 38.5 °C in 5% O …

The Effects Of Providing Social And Nutritional Enrichment To Dairy Calves On Development, Behavior And Learning, Kendra Leigh Kutina

Master's Theses

The objective of this study was to measure the effects of both a nutritional (water nipple) and social (partner calf) enrichment on calf body weight, grain intake, water intake, behavior and learning. The enrichments included 1) water provided from a nipple vs. a bucket (nutritional) and 2) visual and tactile access to a partner vs. isolated rearing with no visual or tactile access to a partner calf (social). A total of 72 Holstein and Jersey dairy calves were pseudo-randomly distributed into 4 treatments at birth [Individual/Bucket (IB), Paired/Bucket (PB), Individual/Nipple (IN), Paired/Nipple (PN)]. Socially and nutritionally enriched calves drank more …

What’S At Steak? The Political Discourse Of Emissions Intensity And Implications Of Animal Agriculture, Kalyn Simon

Master's Theses

This thesis analyzes the international discourse of greenhouse gas emissions in relation to livestock production. Specific government ministries, research institutes, and multilateral organizations are framing a new strategy to mitigate emissions by using emissions intensity metrics. Emissions intensity is a ratio comparing emissions produced per unit of animal product as oppose to measuring absolute emissions. This research is acknowledged as a win-win scenario which allows for a reduction of greenhouse gas emissions while continuing production more efficiently. This thesis outlines the emergence of this metric in international discourse and the implications this shift has on the livestock sector globally. Ultimately, …

Study Of Rehydration Properties Of Powder Produced From Chelated Skim Milk, Kristina Ellice Tan

Master's Theses

Poor rehydration properties of skim milk powder (SMP) can impact processing efficiency and functionality in finished product applications. Rehydration can be split into four stages: wettability, sinkability, dispersibility, and solubility. Previous work has suggested that chelator addition during SMP manufacture leads to higher solubility compared to SMP without chelators. This study focuses on the addition of ethylene diamine tetraacetic acid (EDTA) or sodium citrate dihydrate (SCD) at concentrations of 5, 10, and 15 mM to skim milk prior to evaporating and spray drying. The objective of this investigation was to determine the effects of the chelator additions on each SMP …

Comparison Of Foaming Properties Between Chelated Reconstituted Smp And Caseinates, Boya Liu

Master's Theses

Caseinate powders have been well accepted because of their foaming properties. In this study, 10% solution of reconstituted skim milk powder (SMP) chelated with sodium hexametaphosphate (SHMP) and trisodium citrate (TSC) at 1 mEq, 50 mEq, and 100 mEq were prepared to conduct a comparison with sodium caseinate, potassium caseinate, and calcium caseinate solutions. Foamability, foam stability as well as the preferential locations of αs-casein, β-casein and !-casein in their foams were analyzed. It was hypothesized that the foamability, foam stability and the preferential locations of these three caseins in the milk foams are different from treatment to treatment. Milk …

Separation And Characterization Of Reconstituted Skim Milk Powder Treated With Mineral Chelators, Amy Kringle

Master's Theses

The proteins found in milk are largely important in the functionality of many dairy products and dairy processes. The casein micelle system in milk is a complex and highly studied system. The micelle is thought to be a sponge like structure containing four caseins, α_s1, α_s2, β, and κ casein, and bound together with colloidal calcium phosphate. When a chelating agent such as a citrate, phosphate, or polyphosphate are added to milk systems, the CCP is bound to the chelator and removed from the micelle. It has been shown through past research that the use of …

Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson

Master's Theses

Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.

In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …

The Efficacy Of Antibiotic Residue Screening Tests For The Detection Of Natural Antimicrobials In Milk, Stacey L. O'Donnell

Master's Theses

No abstract provided.

The Expression Of T-Box (Tbx3) In The Bovine Mammary Gland, Maria L. Procopio Ms.

Master's Theses

Development of the bovine mammary gland is a complex process that is regulated by several hormones, growth factors and transcription factors including but not limited to growth hormone (GH), insulin-like growth factor (IGF)-I and T-box (Tbx)2 and 3. Tbx2 and Tbx3 are transcription factors required for mammary gland development in humans and known to regulate cell cycle. In addition, there is recent evidence that GH increases expression of Tbx3 in osteoblasts independent of IGF-I. Based on these findings, we hypothesized GH and IGF-I will increase Tbx2 and Tbx3 expression in bovine mammary epithelial cells (MEC), the cell responsible for milk …

Studying Milk Coagulation Kinetics With Laser Scanning Confocal Microscopy, Image Processing, And Computational Modeling, Richard Joseph Hennessy

Master's Theses

The kinetics of milk coagulation are complex and still not well understood. A deeper understanding of coagulation and the impact of the relevant factors would aid in both cheese manufacturing and also in determining the nutritional benefits of dairy products. A method using confocal microscopy was developed to follow the movement of milk fat globules and the formation of a milk protein network during the enzyme-induced coagulation of milk. Image processing methods were then used to quantify the rate of coagulation. It was found that the texture of the protein network is an indicator of the current status of the …

The Development Of A Novel Technique To Evaluate Binding Between Probiotic Bacteria And Phospholipids, And The Creation Of A Dairy-Based Food Product Rich In Milk Bioactives, Megan Ann Cleveland

Master's Theses

Probiotic bacteria are increasingly prevalent in food and nutritional products today. These remarkable microorganisms are capable of imparting exceptional health benefits on their host, including prevention of infection by pathogens and stimulation of immune system function. Their most common mode of delivery is through dairy products (e.g. yogurt), which are also one of their preferred habitats. The interactions between probiotic bacteria and dairy systems have been studied, but are still not well discerned. There is a need for better understanding of these associations, as well as those surrounding the mode of bacterial transfer from the food product to the human …

Effects Of Filtration Temperature And Heat Treatment On Composition And Rheological Properties Of Whole Milk Ultrafiltration Retentates, John W. Montella

Master's Theses

ABSTRACT

Effects of Filtration Temperature and Heat Treatment on Composition and Rheological Properties of Whole Milk Ultrafiltration Retentates

John William Montella

For the first part of my thesis, the effects of filtration temperature and heat treatment on the compositional properties of whole milk Ultrafiltration retentate (UF) were studied. Ultrafiltration is primarily run at temperatures in the range of 50-55°C but more and more plants are starting to filter at refrigeration temperatures. In the ultrafiltration of milk, filtration temperature can affect the composition of the retentate by affecting the chemistry of milk components. The application of a pasteurization step can also …

Regulatory Cell Biology Of Growth Hormone And Prolactin In The Cow Mammary Gland, David Andrew Walkup

Master's Theses

Prolactin (PRL) acts directly on milk secretory cell nuclei to stimulate lactation in rats. In the cow, PRL has been detected in Golgi apparatus, endoplasmic reticulum, and secretory vesicle subcellular fractions of mammary gland , but not nuclear fractions. However, growth hormone {GH) is the galactopoeitic hormone in cows, not PRL. The possibility of GH acting directly on the cow milk secretory cells, and PRL acting on their nuclei was investigated using an immunocytochemical method. PRL and GH were detected in endoplasmic reticular and Golgi apparatus regions of the milk secretory cells, as well as, on nuclear and fat globule …