Türkiye’nin Ege Bölgesi’ndeki ruhsatlı deney hayvanı tesislerinden laboratuvar farelerinde Salmonella spp.’nin moleküler taraması

Abstract

Laboratuvar fareleri biyomedikal araştırmalarda yaygın olarak kullanılmakta olup, deney hayvanı kolonilerinin mikrobiyolojik statüsü deneylerin tekrarlanabilirliğini, hayvan refahını ve mesleki sağlığı etkileyen kritik bir faktördür. Zoonotik etkenler arasında Salmonella spp., laboratuvar kemirgenlerinde enfeksiyonların sıklıkla asemptomatik seyretmesi ve aralıklı dışkı ile saçılımla karakterize olması nedeniyle rutin sürveyans gerektiren önemli bir patojen olmaya devam etmektedir. Türkiye’de laboratuvar farelerinde Salmonella spp. ile ilgili veriler son derece sınırlıdır ve moleküler tarama çalışmaları azdır. Bu çalışmanın amacı, Türkiye’nin Ege Bölgesi’ndeki ruhsatlı deney hayvanı tesislerinde barındırılan laboratuvar farelerinde Salmonella spp.’nin invazyon geni (invA) hedeflenerek moleküler yaklaşımla taranmasıdır. On bir ruhsatlı tesisten toplam 110 laboratuvar faresinden dışkı örnekleri toplanmıştır. Genomik DNA dışkı örneklerinden ekstrakte edilmiş ve invA’ya özgü primerler kullanılarak konvansiyonel polimeraz zincir reaksiyonu (PCR) ile analiz edilmiştir. PCR-pozitif örnekler iki farklı tesiste belirlenmiştir. Salmonella spp. DNA’sı 110 örneğin 3’ünde saptanmış olup, bu durum %2,7’lik genel prevalansa ve %95 güven aralığına (Wilson skoru) göre %0,93–%7,71 değerlerine karşılık gelmektedir. Sonuç olarak, Türkiye’nin Ege Bölgesi’ndeki laboratuvar farelerinde Salmonella spp. düşük prevalansta saptanmıştır. Tesislerin çoğu negatif olmakla birlikte, sporadik pozitif vakaların belirlenmesi Salmonella spp.’nin laboratuvar fare kolonilerinden tamamen elimine edilmediğini göstermektedir. Bu bulgular, hayvan refahı ve deneysel güvenilirliğin sağlanması için rutin moleküler sürveyansın ve Federation of European Laboratory Animal Science Associations (FELASA) temelli sağlık izlem programlarının önemini vurgulamaktadır.

Keywords

• Biyogüvenlik
• FELASA
• invA geni
• Laboratuvar fareleri
• Salmonella

Presence of Salmonella spp. in Laboratory Mice from Licensed Experimental Animal Facilities in the Aegean Region of Türkiye

Abstract

Laboratory mice are widely used in biomedical research, and the microbiological status of laboratory animal colonies is a critical factor affecting experimental reproducibility, animal welfare, and occupational health. Among zoonotic agents, Salmonella spp. remains an important pathogen requiring routine surveillance, as infections in laboratory rodents are often asymptomatic and characterized by intermittent faecal shedding. In Türkiye, data on Salmonella spp. in laboratory mice are extremely limited, and molecular screening studies are scarce. The aim of this study was to perform molecular screening for Salmonella spp. in laboratory mice housed in licensed experimental animal facilities in the Aegean Region of Türkiye using a molecular approach targeting the invasion gene (invA). Faecal samples were collected from 110 laboratory mice from 11 licensed facilities. Genomic DNA was extracted from faecal samples and analyzed by conventional polymerase chain reaction (PCR) using invA-specific primers. PCR positive samples were identified in two different facilities. Salmonella spp. DNA was detected in 3 out of 110 samples, corresponding to an overall prevalence of 2.7% with a 95% confidence interval (Wilson score) of 0.93%–7.71%. In conclusion, Salmonella spp. was detected at a low prevalence in laboratory mice in the Aegean Region of Türkiye. Although most facilities were negative, the identification of sporadic positive cases indicates that Salmonella spp. has not been completely eliminated from laboratory mouse colonies. These findings emphasize the importance of routine molecular surveillance and the Federation of European Laboratory Animal Science Associations (FELASA) based health monitoring programs to ensure animal welfare and experimental reliability.

Keywords

• Biosecurity
• FELASA
• invA gene
• Laboratory mice
• Salmonella

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