Dairy Science Commons^™

Genetic Selection For Improved Production Efficiency In The Mature Dairy Herd, Maeve Williams

Theses

Improving dairy cow production efficiency is highly desirable because of its well-documented impact on profitability and sustainability. Long-term gains in dairy cow production efficiency have already been delivered through genetic selection. Nonetheless, achieving further improvements in production efficiency could cement the economic and environmental efficiency of the dairy industry, globally. To date, several components contributing to production efficiency have been overlooked, with many studies focusing on dairy cow production efficiency over short periods rather than lifetime efficiency. Therefore, the objectives of this thesis were to quantify the genetic variance components of complementary dairy cow efficiency metrics; including dry matter intake, …

Modelling And Simulation Of Renewable Technologies For Economic And Environmental Analysis And Optimization Of Dairy Farms, Michael Christopher Breen

Theses

The aim of this thesis was to develop a dairy optimisation platform to optimise investments in dairy farm technology and changes to on-farm management practices and electricity tariffs, in order to maximise profitability and minimise environmental impacts. Increased dairy herd sizes and milk production levels in Ireland as well as changing regulations concerning emissions, renewable penetration and energy efficiency have necessitated a means of financial decision support for farmers. Therefore this body of work focused on the creation of a comprehensive method for optimising dairy farm technology selection, management practices and electricity tariffs. The measures which could be implemented on …

Inhibition Of Listeria Monocytogenes By Human Gut Bacteria, Patrycja Sylvia Olesky

Masters

Listeria monocytogenes is a foodborne pathogen, which continues to be problematic to the food industry due to its ability survive within food products and persist within food processing environments. The growing trend towards natural food preservatives and antimicrobial agents increases the need for the development of novel, natural anti-Listeria agents. Evidence presented in the literature suggests that the human gut microbiota is a reservoir of novel antimicrobial agents. It was therefore hypothesized that novel anti-Listeria agents are produced by human gut-derived bacteria. The objective of this study was to isolate and characterize gut bacteria with anti-Listeria monocytogenes activity. A total …

Predicting Energy And Water Consumption On Dairy Farms Through Statistical Analysis And Machine-Learning Methods, Philip Shine

Theses

With the abolishment of milking quotas across all European Union member states in April 2015, dairy farmers must adjust their farming practises to minimise milk production costs to adequately prepare for potential periods of reduced revenue. Milk production is an intense energy and water consuming process. Coupled with challenging European greenhouse gas reduction targets and legislation regarding the prevention of groundwater pollution and deterioration, increasing the production of milk in Ireland must be met with the sustainable consumption of on-farm energy and direct water resources, to ensure the future monetary and environmental sustainability of Ireland’s dairy industry. Thus, this body …

The Use Of Machine Learning To Detect Suckling In Pre-Weaned Calves, Sukumar Katamreddy

Theses

The weaning of cattle is a process which is known to be labour intensive and to have stressful effects on both cow and calf Common methods used in the weaning process include the temporary removal of a mother from the calf and manual observation and intervention. Early and speedy weaning is known to have a number of benefits, including health benefits for both cow and calf, additional weight gains for the calves as well as reduced labour and feed requirements. The process known as Two-Stage Weaning is recognised to be an effective low-stress approach to weaning in which the calf …

An Optimal Milk Production Model Selection And Configuration System For Dairy Cows, Fan Zhang

PhDs

Milk production forecasting in the dairy industry has been an independent research topic since the early 20th century. The accurate prediction of milk yield can benefit both the processor (creameries) and the producer (dairy farmer) through developing short-term production schedules, planning long-term road maps, facilitating trade and investment in the dairy industry, improving business operations, optimising the existing infrastructure of the dairy industry, and reducing operating costs. Additionally, due to the innate characteristics of the milk production process, the accurate prediction of milk yield has been a challenging issue in the dairy industry. With the abolishment of EU milk quotas …

The Development Of New Molecular Tools To Detect Mycobacterium Avium Subspecies Paratuberculosis From A Bovine Faecal Environment By Real-Time Pcr, Marcel De Kruijf

Theses

The slow-growing intracellular pathogen Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne’s disease in domesticated and wild ruminants. Johne’s disease inflicts severe annual economic losses to the dairy industry worldwide. This thesis is divided into five chapters that consist of a literature review' chapter and four experimental chapters focusing on MAP strain genotyping and the development of novel molecular MAP detection tools using real-time PCR. Chapter 1 describes published information regarding MAP characteristics, Johne’s disease, MAP genomes, available MAP detection methods, MAP epidemiology and genotyping.

To efficiently control and monitor MAP infection, molecular t>ping of MAP strains provides extensive knowledge …

Low Cost, Multi-Purpose Genotyping Panels For Dairy And Beef Cattle, Michelle Judge

Theses

rhe selection of animals based on DNA has revolutionised animal breeding, but the associated high cost of obtaining genotypes has limited its uptake. The objective of this thesis was to develop a low-cost, low-density, multi-purpose genotyping panel for the procurement of reliable genotype information, and to quantify the long-term consequences of using such low-density genotype panels in breeding programs. The objectives were achieved through a combination of real-life cattle genotype data and simulations to mimic a cattle population. The in-silico development of genotype panels was based on actual genotypes from up to 58,705 beef cattle. Alternative novel strategies were used …

Automating The Milking Process Within A Grass-Based System, John Shortall

Theses

The successful integration of automatic milking (AM) and grazing has resulted in AM becoming a feasible alternative to conventional milking (CM) in pasture-based systems. The objective of this thesis was to establish (i) the social, environmental and economic effects of adopting AM technology and (ii) the factors affecting cow traffic, which once the AM is adopted, can also impact on the sustainability of AM. A theme across this thesis is the examination of AM in the context of a seasonal pasture-based milk production system. Electricity and water meters were installed on seven AM fanns. Milking and livestock/^miscellaneous processes were the …

An Investigation Of The Use Of Natural Agents To Control Mycobacteria, Olga Lesniak

Theses

Economic losses that are caused by Mycobacterium avium paratuberculosis (MAP) infections represent a major obstacle for farmers and also for the dairy industry. In order to control the population of MAP, alternative control agents must be investigated. One of the studies described in this thesis focused on using a bacteriophage therapy based approach to assess its efficacy on simulated industrial environments and food models. Another study described in this thesis investigated the antimicrobial effects of parsley and garlic on a range of mycobacteria species. Both studies used conventional microbiological methods such as plaque assays, AlamarBlue assay (MABA) and growth curves, …

Development And Validation Of Gas Chromatographic Methods For Free Fatty Acid Determination In Dairy Products, David Mannion

Theses

Quantification of free fatty acids (FFA) in dairy products by gas chromatography flame ion'^ation detection is an important requirement for qua'ity, research, nutritional, authenticity and legislative purposes. Common procedures are typically variants of either the fatty acid methyl esterification (FAME) or direct on-column injection methods developed more than two decades ago. This study involved the development of an alternative novel derivatization method using butylation, incorporating automation, reducing solvent usage that is applicable for a wide range of dairy products. The accuracy, precision, linearity, limits of detection and limits of quantification of all three methods were assessed for the quantification of …