Michael A. Tomaszewski

Dairy herd nutritional analysis using knowledge systems techniques

Abstract A knowledge-based system is used to enhance the ability of producers to interact with a large regional and national database in order to interpret useful management information from production data. The system was developed for use on PC class microcomputers by producers wanting assistance in interpreting changes in milk, fat and protein records and their implications for management and feeding. The expertise embodied in the program was acquired from dairy nutrition specialists.

Profit-Maximizing Dairy Sire Selection Package

The Net Present Value Sire Summary Professional Package (NPVSS) is a microcomputer program designed for technical personnel to help dairy producers better manage investments in genetic improvement. NPVSS is written in C language, utilizes the MS-DOS operating system, and requires 256K of RAM. It is menu driven and includes parameter screens to define herd management characteristics of individual producers. Profit rankings of bulls can be generated to evaluate alternative: a) objective functions (selection policies for genetic merit in milk income and type scores), b) herd management performance factors (conception rate, calving interval, age at first calving), and c) economic factors (milk price, semen price, discount rate, planning horizon).

Assessing the comparative economics of a biotechnology: Artificial insemination dairy sires

Much opportunity exists to increase economic returns from the artificial insemination, dairy sire selection decision. This article measures potential returns to producers with alternative objective functions, management and financial characteristics. The costs of wrong decisions from incorrect information are measured by differences between alternative sets of top-20 Holstein sires selected from more than 400 available. Correct specification of the objective function is most important. Determination of planning horizon and conception rate also merits allocation of some scarce management resources. Correct information about length of calving interval, female mortality rate, and opportunity cost of capital, however, is economically inconsequential.

Management information system impact on dairy production for selected herds in Texas

Yearly production and performance data were obtained for dairy herd improvement members in Texas to determine whether on-farm use of a management information system (MIS) quantitatively impacted performance. Data from 66 dairy operations for the years 1983–1996 were evaluated. Herds enrolled in an MIS program increased rolling herd average milk production by 281 kg and received a return on investment of 212%. Most of the increase in production occurred during the initial year of MIS usage. Throughout the study, larger herds and those that increased in size tended to adopt a management information system.

Estimating the effectiveness of extension information systems using farm trials and subjective probabilities

A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between sec and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.