Document Type

Dissertation - Open Access

Award Date


Degree Name

Doctor of Philosophy (PhD)

Department / School

Animal Science

First Advisor

Michael Gonda


Bovine Respiratory Disease, Classroom Assessment Techniques, DNA Pooling


Bovine respiratory disease (BRD) is the leading cause of morbidity and mortality in the cattle industry. The complexity of host, pathogen, and environmental factors contributing to the incidence of BRD necessitate a multifaceted approach to investigate BRD. A greater understanding of pathogenic and genetics factors associated with BRD would improve prevention and treatment of BRD. Due to the complexity of BRD, genetic technologies have been limited in their ability to identify a genetic basis for BRD. Pooling of DNA samples prior to extraction can increase the ability to conduct genotyping studies of complex traits. Once generated, new information and management methods must be disseminated to the livestock industry. Higher education provides the opportunity to train future livestock producers and promote self-directed learning skills. Therefore, our objectives were to 1) investigate the upper nasal microbiome in BRD affected calves prior to weaning, 2) evaluate the accuracy of pooling samples based on equalized white blood cell counts, and 3) determine the effect of classroom assessment techniques in an introductory level animal science course. Nasal swabs were collected from calves prior to, during a BRD outbreak, and following the outbreak. Analysis by sequencing a variable region of the 16s rRNA gene revealed differences in microbial abundance and community diversity associated with BRD incidence. To evaluate accuracy of blood pooling, whole blood samples were collected from 10 bovine animals and pools were constructed based on number of white blood cells, spectrophotometric readings, spectrofluorometric readings, extracted DNA volume, and whole blood volume. The outcome of this study indicates that pooling based on white blood cell count is an accurate pooling method and has less variability among pools compared to all other methods. Finally, a classroom assessment technique (CAT) was administered in an introductory animal science course. Students completed an assessment form at the conclusion of each class and the instructor provided feedback based on the responses at the beginning of the next class period. While there were no differences in student grades, students perceived that the CAT increased their ability to learn and their engagement in the class.

Library of Congress Subject Headings

Cattle -- Respiratory organs -- Diseases.
Cattle -- Molecular genetics.



Number of Pages



South Dakota State University

Included in

Beef Science Commons



Rights Statement

In Copyright