Study zone
Lomé is the capital of Togo, a country located in West Africa. The city is located in the southwest of the country and extends on the shore of the Gulf of Guinea. It occupies a total area of 333 km² with several agglomerations among others: Aflao, Agbalépédo, Akodésséwa, Baguida, Kanyikopé, Kélékougan, Agoè, Zanguéra… It is located 150 kilometers away from Cotonou and 200 kilometers away from Accra (Dao, 2010).
Lomé, the capital is renowned for being an industrial, commercial and administrative city. The study was carried out in December 2019 with traders of poultry products (chicken eggs, broilers, laying hens, traditional hens and frozen hens imported or not) in six (6) markets including Adawlato, Adidogomé, Agoè, Akodesséwa, Gbossimé, and Hedrzanawè.
Collection of data
A preliminary survey was previously carried out on the knowledge, attitudes and practices of the use of antibiotics in the chicken trade. Then samples were taken from its stores for analysis. Business managers were previously informed of the study and their agreements were obtained before the activities were carried out.
The information was collected through a smartphone questionnaire for chicken traders. This questionnaire was designed on Google Form and contains 16 questions to the multiple-choice system, the merchant only having to tick the box corresponding to his choice. This system has the advantage of allowing better rapid exploitation of the data obtained.
All of the data was recorded on Google Form Excel and transferred to the Microsoft Excel 2013 for analysis by SPSS version 25.
Sampling
According to study data previously carried out in Togo in 2015 (Dao, 2010), 264 operators of poultry products were registered in 2010 in the maritime region with 135 operators in Lomé. From this study with a frequency of 50% and a confidence interval of 95% and 5% error, the sample size calculated was 100 operators. As for bacteriological analyzes and the detection of antibiotic residues, 54 meat samples were collected, including 36 from imported and 18 from local, as well as 36 samples of chicken eggs (18 sample from local and 18 sample from imported).
Sample preparation
Chickens are slaughtered in order to remove parts containing muscle, especially the wings and thighs. These pieces are then individually put in freezer bags and then in the freezer at – 18 °C. For frozen chickens, the thighs and wings are taken directly from the carcass.
The eggs were acquired in the six markets of Lomé and stored at the temperature of the Laboratory.
Detection of antibiotic residues
The analyzes took place in the Laboratory of Microbiology and Quality Control of Foodstuffs (LAMICODA) of the Higher School of Biological and Food Techniques (ESTBA) of the University of Lomé.
The alternative analysis method Premi®Test reference RBP 31 / 02-04 / 11 validated by AFNOR was used. It is a rapid test for the preventive detection of antibiotic residues in chicken meat and eggs according to the Method used by Diabangouaya (2017) in her study.
About two (02) cm3 pieces of meat were removed and pressed using a meat press to extract the meat juice. Then 100 µl of the meat juice is transferred to the agar in a Premi®Test vial. After standing for 20 minutes at room temperature, the vials were rinsed twice with distilled water to remove the meat juice. The vials are then incubated at 64 °C for 3 hours. The result is negative if the agar changes from yellow to purple after three (03) hours.
Analysis of bacteriological quality
The bacteriological analyzes took place at the Laboratory of Microbiology and Quality Control of Foodstuffs (LAMICODA) of the Higher School of Biological and Food Techniques of the University of Lomé.
The samples of 10 g are weighed in 100 ml bottles containing 90 ml of Tryptone Salt (TS) for the detection of bacteria. 25 g of samples are weighedin the 250 ml bottles containing 225 ml of Buffered Peptone water (EPT) for the detection of Salmonellasp. The mix (sample and media solution) are mixed according to the standardized methods of the French Association for Standardization (AFNOR). After 45 minutes of resting of the ground material, decimal dilutions of 100, 10-1, 10-2 and 10-3 were made. Different methods were used depending on the germ sought (Table 1).
Table 1:
Different techniques for counting germs
Germs searched
|
Media
|
Standard methods
|
Temperature / incubation time
|
Total mesophilic flora (FMT)
|
PCA
|
NF V08-051, Fév. 1999
|
30°C/24 - 72h
|
Enterobacterium
|
VRBL
|
NF V08-050, Déc. 1992
|
30°C/24 - 48h
|
E. coli
|
CM1046 BrillanceTM Ecoli
|
37°C/24h
|
Sulphite-reducing anaerobes (ASR)
|
TSN
|
XP V08-061, Oct. 1996
|
44°C/48h
|
Staphylococcus aureus
|
BP
|
NF V08-057-1, Nov. 1994
|
37°C/24 – 48h
|
Salmonella sp
|
EPT, Rappaport, Hektoen, API 20 E
|
NF V08-052, Mai 1997
|
37°C/24h/étape
|
PCA: Plate Count Agar; VRBL: Violet Red Bile Lactose Agar; BP: Baird Parker, TSN: Tryptone Sulfite Neomycin; EPT: Buffered Peptone Water.
Statistical analysis
The statistical analysis of sample are done using software SPSS v25. The correlation analysis is done using Pearson test of Khi2 with p value 0.05.