Evaluation of Postmortem Inspection Procedures to Diagnose Bovine Tuberculosis at Debre Birhan Municipal Abattoir

Abstract

Routine meat inspection in the abattoir was used to examine carcass for subsequent approval for consumption. However, the chance of missing lesions results in approval of carcass and/or the offal with lesions of tuberculosis. A cross-sectional study was conducted at Debre Birhan Municipal abattoir from October 2016 to May 2017. Lesion prevalence estimation and two meat inspection procedures’ efficacy evaluation was attempted. The breeds of the animals inspected were zebu breeds. Routine abattoir meat inspection involves visual inspection, palpation and incision of intact organs such as the liver and kidneys, as well as inspection, palpation and incision of tracheobronchial, mediastinal and prescapular lymph nodes. The detailed meat inspection involves inspection of each of the carcass. In this case, the seven lobes of the two lungs, lymph nodes and organs were also thoroughly examined. The cut surfaces were examined under bright light sources for the presence of an abscess, cheesy mass, and tubercles in detail. The study involved and compared both routine and detailed meat inspections at the abattoir. Chi-square test of independence and odds ratio were used to see the association of lesion and different risk factors. Based on detailed meat inspection, the overall lesion prevalence of bovine tuberculosis in the carcass of cattle slaughtered at Debre Birhan municipality abattoir was found to be 4.7% but only 0.5% of the carcass examined had detectable bovine tuberculosis lesions when routine abattoir meat inspection alone was used. The majority of the lesions were distributed to the lungs and associated lymph nodes. There was a significant association (p < 0.05) in TB infection rate and body condition score. In conclusion, this study has clearly indicated the prevalence of bovine tuberculosis lesions in the abattoir that are missed by routine abattoir meat inspection. In addition, it showed low sensitivity of the routine meat inspection procedure used. Hence, our study warrants immediate attention to strengthen the current meat inspection practices at Debre Birhan public abattoir.

Estimated Prevalence of Tuberculosis in Ruminants from Slaughterhouses in Constantine Province (Northeastern Algeria): A 10-Year Retrospective Survey (2011–2020)

“…The routine slaughterhouse inspection, as previously described, included the detection of visible abnormalities, meaning tubercular lesions, on different organs (e.g., lungs, liver, kidneys, uterus, spleen, udder, intestines, etc. ), and lymph nodes [ 10 ]. In addition, incisions were performed in the trachea, bronchial, mediastinal, apical, medial retropharyngeal, submaxillary, mesenteric, hepatic, inguinal, and supramammary lymph nodes.…”

“…Tuberculous animals engender reduced milk and meat production, and significant losses of meat and offal. In addition, morbidity and mortality rates increased considerably, giving rise to additional treatment costs [ 10 ]. In low-income countries, TB is considered one of the most widespread and devastating zoonotic diseases, with a cosmopolitan distribution.…”

“…In Algeria, the livestock, composed mainly of sheep, cattle, goats, and camels are screened yearly on an antemortem basis via a tuberculin skin test, or through a postmortem inspection of the meat in the slaughterhouses [ 16 , 17 ]. Veterinary inspectors perform livestock controls and play an important role in the sanitary surveillance of pulmonary infections [ 10 ]. It is known that slaughterhouse surveillance is regarded as a simple, cost-effective, and fairly reliable method of detecting animals with tuberculous, with a high level of sensitivity [ 18 ].…”

A one health-focused literature review on bovine and zoonotic tuberculosis in Pakistan from the past two decades: challenges and way forward for control

“…Animal owners should be incentivized for screening their animals for bTB and maintenance of disease free herds [ 104 ]. Additionally, inspection of the animals prior to slaughtering and detailed post-mortem inspection (following the protocols implemented in UK and the EU) should be ensured to stop entry of meat of any infected animal into the food chain [ 107 , 108 ]. This should be accompanied by tracing back to the herd to which the diseased animal belonged [ 101 ].…”

Pre-slaughter, slaughter and post-slaughter practices of slaughterhouse workers in Southeast, Nigeria: Animal welfare, meat quality, food safety and public health implications

“…Thorough PMI of carcasses/meats (head, pluck, organs and muscles) was conducted as described by Biffa et al [37] and Woldemariyam et al [38] to determine the presence of lesions of common zoonotic or economically important livestock diseases such as bovine tuberculosis, contagious bovine pleuro-pneumonia, porcine cysticercosis, contagious caprine pleuro-pneumonia and fascioliasis. A minimum sample size of 385 for each of the animal/carcass types was computed for the purposes of PMI study, using the Raosoft 1 sample size calculator freely available online at http://www.raosoft.com/samplesize.htm.…”