ISSN 2375-0693
African Journal of Agricultural Economics and Rural Development ISSN 2375-0693 Vol. 13 (1), pp. 001-027, January, 2025. Available online at www.internationalscholarsjournals.org © International Scholars Journals
Review
Bacterial Pathogen Profiles in Pigs: A Systematic Review and Meta-Analysis Highlighting Escherichia coli
Rukayya Hussain Abubakar1, Evelyn Madoroba2,3, Olubukola Adenubi4, Darshana Morar-Leather1 and Folorunso O. Fasina1,5*
1Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, South Africa.
2Bacteriology Section, Agricultural Research Council–Onderstepoort Veterinary Research, South Africa.
3College of Agriculture and Environmental Sciences, University of South Africa, Florida Campus, South Africa.
4Department of Paraclinical Sciences, Faculty of Veterinary Sciences, University of Pretoria, South Africa .
5Emergency Centre for Transboundary Animal Diseases (ECTAD), Food and Agriculture Organization of the United Nations (FAO), UNON, Gigiri, Kenya. *Corresponding author. E-mail: daydupe2003@yahoo.co.uk. Tel: +27719790042; +254 729840367.
Accepted 15 September, 2024
Abstract
Pigs are ungulate animals of the genus Suis and family Suidae. They are globally spread but restricted in certain countries due to religious and cultural beliefs. Pork serves as an important source of protein (38% of meat consumed in the world). While pig production remains a profitable enterprise, commercial and particularly the small-scale farmers face huge constraint in this husbandry practice, one of the most important being bacterial infections and its associated with morbidity and mortality. In this work, we reviewed the prevalence of bacterial infections in pigs with particular reference to Escherichia coli, a bacterium that is regularly isolated and can lead to multiple infections in pigs. Literatures were searched on selected veterinary and biological data bases in 2016 with focus on natural infections and isolates from natural infections with epidemiological details. Pathotypes, serotypes and serogroups of E. coli, the country of origin, source, growth stage, age of pigs infected, disease outbreak, the number of samples and type of samples, numbers and percentage of positive samples and isolates were used as filters. Pathotypes reported include enterotoxigenic E. coli (ETEC) 66.7%, enterotoxigenic E. coli and shiga toxigenic E. coli (ETEC and STEC) 14.3%, STEC only (7.9%), enterotoxigenic E. coli/enteropathogenic E. coli/enteroaggregative E. coli (ETEC/EPEC/EAE) 31.7%. Others were enterohaemorrhagic E. coli (EHEC), diffusely adherent E. coli (DAEC) (ETEC, EPEC, STEC) and extra-intestinal pathogenic E. coli (ExPEC). Twenty-nine countries with documented records of cases of E. coli were included with the USA reporting, the highest number followed by China. About 74% of the samples were taken from farms and others were from samples submitted to research laboratories and veterinary faculties for necropsy. Serogroups O141, O149, O139, O138, O8 and O9 were most common. Piglets were most affected (52.3%) followed by weaners (39.6%) and porkers (7.9%) with age ranging from 1 to 392 days old. A total of 24,854 isolates were considered, 10477 (42.2%) were positives and the following genes were carried: STa, STb, LT, stx1, stx2, Stx-2e, F4, F5, F6, F18, F41, AIDA, EAST1, eae, paa and hlyA. The diseases produced by E. coli were neonatal diarrhoea, colibacillosis, post-weaning diarrhoea and edema disease. The associated risk factors were poor housing, management and feed changes, extensive use of antibiotics as prophylaxis, overcrowding, and high humidity and temperature changes. India, USA, Japan, Slovakia, Denmark Sweden and Poland were countries with significant reports and high detection of virulence factors (72 to 100%).
Key words: Escherichia coli, diarrhea, serogroups, enterotoxigenic, colibacillosis.