Validation of drop plate technique for bacterial enumeration by parametric and nonparametric tests
Journal Title: Veterinary Research Forum - Year 2013, Vol 4, Issue 3
Abstract
Drop plate technique has a priority and preference compared with the spread plate procedure, because of less time, quantity of media, effort requirement, little incubator space, and less labor intensive. The objective of this research was to compare the accuracy and fidelity of drop plate method vs. spread plate method by parametric and nonparametric statistical tests. For bacterial enumeration by drop and spread plate methods, successive dilutions of second subculture of Lactobacillus casei and Salmonella Typhimurium were transferred to selective agar. The correlation of agreement between both methods was evaluated by using statistical proofs. Results showed that mean value (parametric unpaired t-test) comparison at 95 percent confidence level did not reject null hypothesis, which it meant that the equality of the mean data could not be ruled out. Nonparametric method was used because of approximately Gaussian pattern of data distribution. For this purpose, Mann-Whitney test (equivalent nonparametric t-test) was used. It meant that the equality of medians obtained from two methods were similar. Spearman’s rho correlation coefficient (r) via both methods due to data distribution patterns for enumeration of S. Typhimurium and L. casei were 0.62 and 0.87, respectively; which represented moderately strong and strong relationship between two methods, respectively. Besides, there was a significant and strong positive correlation (p < 0.001) between spread and drop plate procedures. Because of aforementioned reasons, the spread plate method can be replaced by drop plate method.
Authors and Affiliations
Hossein Naghili, Karim Mardani, Seyed Mehdi Razavi Rouhani Razavi Rouhani, Ali Ehsani, Payman Zare
Keywords
Related Articles
- EP ID EP120487
- DOI -
- Views 118
- Downloads 0
Protective effects of pomegranate seed oil on ovariectomized rats as a model of postmenopausal osteoporosis: A multi-detector computed tomography evaluation
The pomegranate seed oil (PSO), containing 17-α-estradiol, is one of the newly found phytosterols with synergistic health effects on estrogen related physiological conditions. Herein, PSO was assessed for its potential i...
Chemical composition and in vitro antibacterial activity of essential oil and methanol extract of Echinophora platyloba D.C against some of food-borne pathogenic bacteria
Echinophora Platyloba D.C as a medicinal plant is used for preservation of foods and treatment of many diseases in different regions of Iran. The present study was undertaken to determine the chemical composition and inv...
Effects of chicory root powder on growth performance and histomorphometry of jejunum in broiler chicks
In the present study, chicory root powder (CRP) as growth promoter at 1% and 3% levels was supplemented in broilers’ diet to investigate the growth performance and histo-morphometry of jejunum. One hundred twenty, one-da...
Ameliorative properties of aqueous extract of Ficus thonningii on erythrocyte osmotic fragility induced by acetaminophen in Rattus norvegicus
In vitro antioxidant and erythrocyte protecting activities by aqueous extract of Ficus thonningii leaves on blood cells were studied in acetaminophen treated rats. The extract was safe at limit dose of 5000 mg kg-1 body...
Histomorphometric study of on blood cells in male adult ostrich
In order to perform a histomorphometric study of blood cells in male adult ostrich, blood samples were obtained from jugular vein of 10 clinically healthy male adult ostriches (2 - 3 years old). The slides were stained w...