PCR tech. lowers diagnostic testing costs for dairies

Researchers at CentralStar Cooperative develop and validate a new low-cost PCR system

Dairy veterinarians and producers now have access to low-cost quantitative polymerase chain reaction (PCR) assays to more effectively detect and manage bovine leukosis virus (BLV) and contagious mastitis; as well as genotyping beta-casein allele A1/A2. Recently researchers at CentralStar Cooperative developed and validated a new low-cost PCR system that leverages the sensitivity and specificity of this technology which is widely used in human and companion animal medicine.

“PCR has become a ubiquitous and versatile tool for interrogating genetics, and for the detection of pathogens, however has historically been cost-prohibitive for most producers to utilize so we aimed to change that,” said Dr. Casey Droscha, Associate Director of Research and Development, CentralStar Cooperative. “Our research team has automated the extraction of nucleic acid for all sample types, including blood, milk, feces and tissue, and optimized the performance of our new lineup of tests.”

Compared to traditional culture-based pathogen testing methods, PCR assays are faster, more sensitive and more specific by quantitatively detecting signature DNA sequences of multiple pathogens at one time. In line with methodologies used in forensic science, PCR is capable of amplifying trace amounts of DNA and ribonucleic acid (RNA) located in or on almost any liquid or surface where DNA strands may be deposited.

Through the development of this lower-cost PCR system, CentralStar researchers designed three new tests. The BLV Super-Shedders (SS1) PCR assay determines the concentration of the proviral DNA of the bovine leukosis virus in a cow’s blood, identifying the most infectious cows (super-shedders) in a dairy herd. Developed in collaboration with Michigan State University (MSU) and funded through the United States Department of Agriculture (USDA), CentralStar research demonstrates that focusing management on super-shedders, instead of all infected cows, is the first step towards BLV eradication.

The single-target mastitis PCR assay was developed for contagious pathogens commonly found in dairy herds; Staphylococcus aureus and Mycoplasma bovis. Dairy herds battling high somatic cell counts (SCC) can use this test for greater analytical sensitivity and lower cost compared to traditional methods.

The beta-casein genotyping (A1/A2) assay was developed as an unofficial test to assist with breeding decisions in dairy herds. Research suggests the A2 isoform of beta-casein is more preferentially digested than the A1 isoform, leading some herds to select for A2/A2 genotypes to enhance the market value of their milk.

 

 

A 75-year-old cooperative, CentralStar began providing laboratory services to the dairy industry in 1999 with Dairy Herd Information (DHI) milk analysis. Since then, CentralStar’s investment in research has introduced a series of novel diagnostic tests for Johne’s, bovine viral diarrhea (BVD), BLV, neospora, mastitis, and pregnancy. Through industry and academia collaborations, research interests now span the globe keeping CentralStar at the forefront of advancing agricultural technologies.

CentralStar’s goal of enhancing producer profitability through integrated services is fulfilled by incorporating an array of products and services critical to dairy and beef farm prosperity. CentralStar’s product and service offerings include Accelerated Genetics, GenerVations and Select Sires genetics; extensive artificial-insemination (A.I.) service; genetic, reproduction, and dairy records consultation; DHI services; diagnostic testing; herd-management products; research and development; and more. CentralStar’s administration and warehouse facilities are in Lansing, Mich., and Waupun, Wis., with laboratories in Grand Ledge, Mich., and Kaukauna, Wis. For more information, visit CentralStar Cooperative Inc. www.mycentralstar.com/diagnostic-services