Detection of Mycobacterium avium subsp. paratuberculosis in reproductive tissue and semen of naturally infected rams

José Vicente Velázquez-Morales,César Cortez-Romero,Jaime Gallegos-Sánchez,Marco Antonio Santillán-Flores,Juan Manuel Cuca-García,Reyna Isabel Rojas-Martínez,María Del Carmen Navarro-Maldonado

doi:10.21451/1984-3143-ar2018-0147

Abstract

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis (PTB), disease that causes a syndrome of bad nutrient absorption, weight loss and eventually death. The intestine is the main target organ where the infection develops; however, there is evidence of infection by MAP in extra-intestine sites of sheep, including mesenteric nodes and semen. The aim of the study was to identify the presence of MAP in reproductive tissue and semen of infected Pelibuey rams in clinical state of PTB. Seven rams were used in clinical PTB state and a non-infected ram by MAP of the Pelibuey breed, confirmed by serology, nPCR and bacteriological culture, with average weight and age of 57.23 ± 1.73 kg and 2.91 ± 0.17 years, respectively. The presence of MAP was identified in different tissue samples: spleen (1/7, 14.3% and 2/7, 28.6%), small intestine (3/7, 42.9% and 4/7, 57.1%) and mesenteric lymph nodes (3/7, 42.9% and 3/7, 42.9%), with nPCR and culture, respectively. It was also identified in epididymis tissue (1/7, 14.3%), Cowper gland (2/7, 28.6%) and prostate (1/7, 14.3%), using nPCR, although without detection in culture. It was identified in testicular tissue in 42.8% (3/7; culture or nPCR technique), but in 28.6% (2/7) with both techniques. Finally, the presence of MAP was identified in 42.9% (3/7) of semen samples with nPCR; however, it was not detected through culture. In conclusion, the presence of MAP was identified in lymphatic, digestive tissue, and semen; the presence of MAP was reported for the first time in epididymis, Cowper gland, prostate and testicles of infected Pelibuey rams.

Highlights

PTB or Jhone disease is chronic consumptive and incurable, caused by Mycobacterium avium subsp. paratuberculosis (MAP); intracellular mycobacteria of slow growth, Gram positive, anaerobic, which has 14 to 18 copies of an insertion element called insertion 900 (IS900) in its genotype (Ayele et al, 2001, 2004)
The nested PCR (nPCR) allowed identifying the presence of MAP in semen of infected rams, when visualizing a 210 pb band in amplified products (Figure 1)
It has been reported that the presence of these signs are due to the diffuse hypertrophy caused in the mucosa of the jejunum and ileum, which provokes macroscopic thickening of the intestinal wall; these granulomatous lesions are caused by MAP and generate bad absorption of nutrients, provoking loss in body condition (Clarke, 1997; Verin et al, 2016)

Summary

Introduction

PTB or Jhone disease is chronic consumptive and incurable, caused by MAP; intracellular mycobacteria of slow growth, Gram positive, anaerobic, which has 14 to 18 copies of an insertion element called IS900 in its genotype (Ayele et al, 2001, 2004). It is a disease typical of ruminants (García and Shalloo, 2015), it infects monogastric animals and wild birds (Ayele et al, 2001; Pieper et al, 2014), causing chronic gastroenteritis with lymphangiectasia and lymphangitis; these lesions generate the appearance of the syndrome of bad nutrient absorption, weight loss, chronic or intermittent diarrhea, causing weakness and eventually death (Chiodini et al, 1984; Whittington et al, 2012; Mcgregor et al, 2015). No histological lesions have been observed in bovine testicle, the presence of MAP in this tissue has been determined, with the culture and polymerase chain reaction (PCR) technique (Glawischnig et al, 2004)

Objectives

Methods

Results

Conclusion