The use of infrared thermography as a non-invasive method for fever detection in sheep infected with bluetongue virus.
Fever, which is closely linked to viraemia, is considered to be both the main and the earliest clinical sign in sheep infected with bluetongue virus (BTV). The aim of this study was to evaluate the potential use of infrared thermography (IRT) for early detection of fever in sheep experimentally infected with bluetongue virus serotype 1 (BTV-1) and serotype 8 (BTV-8). This would reduce animal stress during experimental assays and assist in the development of a screening method for the identification of fever in animals suspected of being infected with BTV. Rectal and infrared eye temperatures were collected before and after BTV inoculation. The two temperature measures were positively correlated (r=0.504, P<0.05). The highest correlation between rectal and infrared temperatures was observed when temperatures were above physiological levels. IRT discriminated between febrile and non-febrile sheep with a sensitivity of 85% and specificity of 97%. The results showed that eye temperature measured using IRT was a useful non-invasive method for the assessment of fever in sheep infected with BTV under experimental conditions. Further research is required to evaluate the use of IRT under field conditions to identify potentially infected animals in bluetongue surveillance programmes.
VISAVET Center and Animal Health Department, Veterinary School, University Complutense of Madrid, Avenida Puerta de Hierro s/n, 28040 Madrid, Spain. Electronic address: anacristina@sanidadanimal.info.
Ana C
AC
Pérez de Diego
Pedro J
PJ
Sánchez-Cordón
Miriam
M
Pedrera
Beatriz
B
Martínez-López
José C
JC
Gómez-Villamandos
José M
JM
Sánchez-Vizcaíno
D000818:Animals; D001819:Bluetongue / Q000175:diagnosis* / Q000821:virology; D001820:Bluetongue virus / Q000235:genetics / Q000302:isolation & purification*; D001831:Body Temperature; D005334:Fever / Q000175:diagnosis / Q000662:veterinary* / Q000821:virology; D008297:Male; D012367:RNA, Viral / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D012007:Rectum / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D012680:Sensitivity and Specificity; D012756:Sheep; D013817:Thermography / Q000379:methods* / Q000662:veterinary; D014766:Viremia / Q000175:diagnosis / Q000662:veterinary* / Q000821:virology
D012367:RNA, Viral
Bluetongue; Fever detection; Infrared thermography; Sheep