Three Essays On The Economics Of Dairy Nutrition And Disease Control

Abstract

This dissertation consists of three essays on the economics of dairy nutrition and disease control, in particular, productivity and profitability associated with the dairy industry. The first essay examines the effect of a dairy feed supplement on milk production and profitability of dairy operations. The second essay develops a conceptual model for examining infectious disease control in livestock using Mycobacterium avium ssp. paratuberculosis (MAP) and Johne's disease (JD) control in dairy herds as an example. The third essay looks into the economic and epidemiological consequences of current and next generation vaccines for MAP and JD in dairy herds. Chapter 1 examines the profitability of rumen-protected methionine (RPMet) supplement on milk protein production. The additional daily profit per cow potentially earned by adding various amounts of RPMet supplement to the diet of lactating cows is analyzed and reported. The optimal amount of RPMet reported to maximize daily profit per cow is compared to the RPMet required to maximize milk protein production. These optimal quantities are very similar given current prices for RPMet and milk protein. Chapter 2 presents a conceptual framework for evaluating the economics of infectious disease control for livestock. An animal compartment model is used to develop a conceptual model that incorporates the complexity inherent in disease-specific epidemiology in livestock. This conceptual model is empirically applied with a discrete optimal control model maximizing net present value to evaluate the economic and epidemiological consequences of various control strategies for MAP, the pathogen causing Johne's disease in dairy herds. Chapter 3 investigates the epidemiological impacts and economic values of hypothetical MAP vaccines in dairy herds. Scenarios for the potential epidemiological impacts of MAP vaccines are created, and then economically justifiable values are estimated at which they would be cost-effective to dairy producers. The estimated economic values of MAP vaccines suggest that some vaccinations can be an economically attractive method of MAP control for dairy producers.