A recent study, funded by the Swine Health Information Center and led by Drs. Cesar Corzo and Marcello Melini at the University of Minnesota, explored the use of tongue tip samples as a viable option for effective disease diagnosis in growing pigs. The industry summary for the SHIC project #23-063 can be found here. Inspired by this project to continue exploring alternative sample types that can be used for swine diagnostics, Drs. Corzo and Melini completed another study to investigate cardiac puncture (CP) blood collection as a practical and biosecure method for post-mortem pathogen detection in pigs. Published in January 2026, the full study is now available in Frontiers in Veterinary Science.
In routine farm settings, sample collection often depends on ease, staff expertise, and the suspected pathogen, yet it must always be guided by a clear diagnostic purpose. Through investigating alternative sample types, researchers sought to identify appropriate, efficient, and easy-to-obtain samples from swine mortalities for pathogen detection. Additionally, project goals included identifying sample types that minimize the risk of environmental contamination which can lead to disease transmission as compared to traditional sample collection through necropsy or tongue-tip fluids.
Researchers investigated post-mortem CP as a minimally invasive, animal-welfare friendly and biosecure alternative that has shown promise for detecting PRRSV and could enhance diagnostic safety during endemic, emerging and foreign animal disease investigations. In the published study report, authors wrote, “This method was not only feasible for obtaining blood and testing the sera, but also avoided environmental contamination with blood, offering an alternative tool for collection during outbreak investigations.”
For this project, blood samples were collected at five Midwestern US farms, three of which were breed-to-wean operations and two of which were growing pig farms undergoing a PRRSV outbreak. To perform the study, researchers collected a total of 286 CP blood samples originating from 196 suckling and 90 growing pigs. Reported outcomes included nine cases where sample collection did not yield enough serum volume for testing, and four instances where the PCR reaction was inhibited. Among the remaining samples, PRRSV was detected in 95% of samples with a median cycle threshold value of 21.5 (Q1 17.1; Q3 28.5), a minimum of 10.8, and a maximum of 35.5.
CP offers a practical and safe alternative for specimen collection during infectious disease investigations in swine. While collection of pre-mortem blood samples remains a preferred diagnostic sample type due to its reliability, post-mortem CP provides an efficient way to obtain blood for pathogen detection without the extensive tissue disruption associated with necropsy. The study notes that necropsy-based sampling, though common for assessing lesions and collecting tissues for histology or molecular testing, often results in blood spillage. This can increase the risk of environmental contamination—a particular concern for highly stable viruses such as African swine fever virus, which can persist in blood for extended periods.
This sampling method should serve as a complementary tool during outbreak investigations, since CP is not meant to substitute for a full necropsy, which remains essential for confirming diagnoses in clinically affected pigs. The study summary states, “Blood collection from dead pigs is a viable welfare-friendly alternative for PRRSV detection. After training to collect this specimen, CP is an alternative to obtaining a blood sample for surveillance and diagnosis of pathogens of interest (i.e., PRRSV, ASF, CSF) while minimizing blood spillage and environmental contamination, which can increase the risk of pathogen dissemination.”
Click here to see more...