García CL, Socci EG, Barrón FL, Arriaga DC, Morilla GA

Language: English/Spanish
References: 11
Page: 263-267
PDF size: 855.80 Kb.

ABSTRACT

Porcine ileitis is a disease that causes important economical losses to the swine industry. The causing agent of this disease is Lawsonia intracellularis which is a microorganism difficult to culture. For this reason, diagnosis is usually performed only at slaughter. Due to the difficulties of diagnosis in live animals, techniques based on the amplification of the bacterial DNA by the polymerase chain reaction (PCR) have been developed. The aim of this work was to evaluate a PCR technique to diagnose porcine ileitis in intestinal mucosa and fecal samples from swine suspected of being infected. DNA was extracted using diatomaceous earth and guanidine thiocyanate. Specific oligonucleotides that amplify a 319 bp DNA fragment of L. intracellularis DNA were used in the PCR. For standardization of the technique, intestinal mucosa samples from an experimentally infected pig were used. The minimum amount of infected mucosa DNA that was detected by PCR was 3.72 ng. When the infected mucosa was added to normal fecal samples, 12.4 ng of the extracted DNA were necessary to obtain a visible amplification product. The expected amplification product of 319 bp was also obtained from intestinal mucosa or fecal samples from pigs with characteristic clinical signs of porcine ileitis. It is concluded that the PCR technique could be very useful for the diagnosis of this disease, and for the determination of the prevalence of porcine ileitis in different areas.

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