Traceability of animal protein byproducts in ruminants by multivariate analysis of isotope ratio mass spectrometry to prevent transmission of prion diseases

 

Rui Seabra Ferreira Jr.^1 2, Daniela Alessandra Fossato da Silva¹, Natália Perussi Biscola^1 6, Maria Márcia Pereira Sartori³, Juliana Célia Denadai⁴, André Mendes Jorge⁵, Lucilene Delazari dos Santos^1 2, Benedito Barraviera^1 2

 

1 Center for the Study of Venoms and Venomous Animals (CEVAP), UNESP - São Paulo State University, Botucatu, SP, Brazil

2 Botucatu Medical School, UNESP - São Paulo State University, Botucatu, SP, Brazil

3 College of Agricultural Sciences (FCA), UNESP - São Paulo State University, Botucatu, SP, Brazil

4 Stable Isotopes Center (CIE), UNESP - São Paulo State University, Botucatu, SP, Brazil

5 College of Veterinary Medicine and Animal Husbandry (FMVZ), UNESP - São Paulo State University, Botucatu, SP, Brazil

6 Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA

 

ABSTRACT

Background:

Ruminant feed containing animal byproduct proteins (ABPs) is prohibited in many countries due to its risk of transmitting prion diseases (PD). In most cases the entire herd is sacrificed, which causes great harm to the producer countries by preventing their exportation of ruminant derived-products.

Methods:

We used stable isotope ratio mass spectrometry (IRMS) of carbon (¹³C/¹²C) and nitrogen (¹⁵N/¹⁴N) to trace the animal protein in the blood of 15 buffaloes (Bubalus bubalis) divided into three experimental groups: 1 - received only vegetable protein (VP) during 117 days; 2 - received animal and vegetable protein (AVP); and 3 - received animal and vegetable protein with animal protein subsequently removed (AVPR). Groups 2 and 3 received diets containing 13.7% bovine meat and bone meal (MBM) added to a vegetable diet (from days 21-117 in the AVP group and until day 47 in the AVPR group, when MBM was removed).

Results:

On the 36th day, differences were detectable in the feeding profile (p <0.01) among the three experimental groups, which remained for a further 49 days (85th day). The AVPR group showed isotopic rate reversibility on the 110th day by presenting values similar to those in the control group (VP) (p> 0.05), indicating that it took 63 days to eliminate MBM in this group. Total atoms exchange (> 95%) of ¹³C and ¹⁵N was observed through incorporation of the diet into the AVP and AVPR groups.

Conclusions:

IRMS is an accurate and sensitive technique for tracing the feeding profile of ruminants through blood analysis, thus enabling investigation of ABP use.

 

Keywords: prion diseases; monitoring; bovine spongiform; encephalopathy; stable isotopes

 

Received: August 22, 2018.

Accepted: December 03, 2018.

 

Correspondence: rui.seabra@unesp.br

 

Competing interests RSFJr and BB are employees of CEVAP-UNESP, which is a public manufacturer of recombinant and plasma‐derived medicinal products to translational research.

 

Authors' contributions

RSFJ conceived of the presented idea and supervised the project. DAFS and NPB verified the analytical methods. MMPS and JCD developed the theory and performed the computations. AMJ and LDS supervised the findings of this work. BB conceived of the presented idea and supervised the project. All authors discussed the results and contributed to the final manuscript.