Salmonella Characterization in Poultry Eggs Sold in Farms and Markets in Relation to Handling and Biosecurity Practices in Ogun State, Nigeria

Prevalence and serotype of poultry salmonellosis in Africa: a systematic review and meta-analysis

RESEARCH HIGHLIGHTS

The pooled sample prevalence of poultry salmonellosis in Africa is high (14.4%).The highest PPE was recorded in meat and meat products.Salmonella serotypes of zoonotic importance were found in all sample types.Salmonella Enteritidis and Typhimurium are common serotypes spreading in Africa.

Anti-Salmonella activity of plant species in the Benin republic: Artemisia afra and Detarium senegalense with promising in vitro and in vivo activities

Non-typhoidal invasive Salmonella (NTiS) diseases are one of the most important zoonoses in the world. This study explored the antipathogenic potential of twenty-four plants used in Benin folk medicine against NTiS diseases. The in vitro antibacterial and antibiofilm activities of ethanolic plant extracts were screened against clinical resistant isolates and ATCC reference strains of Salmonella. Salmonella enterica serovar Typhimurium-infected rat model was used to examine the in vivo antibacterial potential of plant extracts. Of the 24 plants, 18 plants exhibited antibacterial activity against Salmonella enterica strains with minimum inhibitory concentrations (MICs) ranging from 0.156 to 1.25 mg/mL. Anacardium occidentale, Artemisia afra, Detarium microcarpum, Detarium senegalense, and Leucaena leucocephala were the most active plant species. Extracts from A. afra, D. microcarpum, and D. senegalense showed biofilm inhibition greater than 50% against Salmonella clinical isolates. In the rat model of infection, A. afra and D. senegalense extracts were found to have an effective dose of less than 100 mg/kg and to stop the salmonellosis after 10 days of treatment. Additionally, these extracts did not produce any toxic effects in the treated animals. These results indicate clear evidence supporting the anti-Salmonella activity of A. afra and D. senegalense. Further studies are now needed to isolate bioactive compounds and to ensure the safety of these plant species.

The Occurrence and Genomic Characteristics of mcr-1-Harboring Salmonella from Retail Meats and Eggs in Qingdao, China

Salmonella are widely distributed foodborne pathogens and are often associated with food animal products. Colistin resistance mediated by mcr-1 is an increasing threat; however, data on the characteristics of mcr-1-harboring Salmonella among retail foods are still lacking. In this study, retail meats from 24 supermarkets and eggs from nine markets in Qingdao city were investigated to determine the presence and genomic characteristics of mcr-1-harboring Salmonella. We found the retail meats and eggs were highly contaminated by Salmonella, with detection rates of 17.5% (31/177) and 12.3% (16/130), respectively. A total of 76 Salmonella isolates were obtained in this study, and 77.6% showed multidrug resistance (MDR). The MDR proportion of egg isolates (97.5%) was significantly higher than that in meat isolates (55.6%) (p < 0.05). The most prevalent Salmonella serotypes were Typhimurium (56.6%) and Enteritidis (17.1%). Of the 76 Salmonella isolates, 40 possessed mcr-1. All 40 mcr-1-positive isolates were ST34 S. Typhimurium and were from eggs of eight brands. Different mcr-1-harboring isolates existed in the same egg, and some isolates from different egg samples or brands showed clonal relationships. The mcr-1 was located on similar IncHI2/HI2A MDR non-conjugative plasmids lacking transfer region, resulting in the failure of conjugation. The phylogenetic tree using genome sequences showed that the mcr-1-positive isolates from eggs clustered together with mcr-1-positive isolates from chicken and humans in China, revealing that mcr-1-positive egg-borne Salmonella might be derived from chicken and could potentially trigger outbreaks in humans. The high occurrence of mcr-1-harboring Salmonella in fresh eggs is alarming, and there is an urgent need to monitor mcr-1-harboring Salmonella in retail meats and eggs. We report for the first time the role of retail eggs in disseminating mcr-1-positive Salmonella and the risk of transmission of these MDR pathogens from retail food to humans should be evaluated comprehensively.

Consumer attitudes towards egg production systems and hen welfare across the world

Concurrent with the growth of the human population, global egg production has experienced exponential increase in the last 50 years. This exponential growth has been made possible through the refinement of intensive egg production systems, predominately, conventional cages. The significant amount of liberties conventional cages withhold from hens has also formed the basis of growing challenge to the industry in many countries, with some major regions such as the European Union making sweeping regulatory reform. These reforms were driven by well-organised animal advocacy groups, fuelled by aligning consumer attitudes and behaviours. In the absence of concerted hen welfare advocacy and cage-free movement in much of the rest of the world, it is difficult to know what consumer attitudes and knowledge may exist outside the European Union. This study aimed to contribute to this knowledge by surveying 4,292 members of the public at random across 14 geographically and culturally diverse countries (Australia, Bangladesh, Brazil, Chile, China, India, Malaysia, Nigeria, Pakistan, Philippines, Sudan, Thailand, UK and USA). The findings show that most participants across all countries eat eggs, most state that it matters to them that hens do not suffer in the process of producing the eggs they eat, and importantly, a majority of participants in most countries (except Nigeria) would prefer (to varying degrees) to purchase eggs from hens not kept in cages. Participant knowledge of the dominant system of egg production in their country varied greatly, with frequent uncertainty. This suggests a need for clarity and consistency in communication to consumers during campaigns, in order to mitigate confusion. Most importantly, although these similarities existed across the countries, important regional differences were also present. This underscores the importance of understanding animal and agricultural issues by geopolitical region, and of locally tailoring strategy. The findings of this research will be of strategic use to egg producers and animal welfare advocates alike in understanding and appropriately catering to consumers in the future.

Risk Factors for Persistent Infection of Non-Typhoidal Salmonella in Poultry Farms, North Central Nigeria

Salmonellosis is a bacterial zoonosis causing an array of health conditions. Non-typhoidal salmonellosis (NTS) has a discrete adaptation to certain animals; in poultry, pullorum and fowl typhoid are its primary disease manifestations. The diseases are prevalent in Nigerian poultry and have been well-studied in Nigeria, but less so in North Central Nigeria (NCN). Using field sampling, laboratory methods and a semi-structured questionnaire for 1000 poultry farms in NCN, we explored the incidence and risk factors for the persistence of NTS infection in poultry. Approximately 41.6% of the farms had experienced NTS over the last 18 months. Farm experience of NTS moderately predicted awareness of salmonellosis. Increasing stock in smallholder farms, self-mixing of concentrate on the farm, usage of stream water, pen odour, non-adherence and partial adherence of farms to recommended poultry vaccination against pullorum and fowl typhoid and lack of and non-adherence to biosecurity were identified risk factors that increased the odds of NTS infection in poultry. Antibiotic use practice may have reduced the isolation rate of NTS, yet NTS continues to challenge poultry farms in Nigeria. Identified risk practices must be mitigated intentionally and biosecurity and hygiene must be improved to reduce the burden of NTS.