by Animal Food Factory located at Asser Region. Animals slaughtered at the same day and venous blood was collected from each chicken in a tubes containing.
Journal of Applied Sciences Research, 3(12): 1646-1649, 2007 © 2007, INSInet Publication
Clstogenic Analysis of Chicken Farms Using Micronucleus Test in Peripheral Blood Kamel Saleh and Mohammed A.A. Sarhan Department of Biological Sciences, Faculty of Science, King Khalid University, 61413Abha, P.O.Box 9004, Saudi Arabia. Abstract: The Clastogenic effect of chicken food storage was studied using the micronucleus test in erythrocytes from peripheral blood of chicken from different farms. Examination of blood smears showed that the formation of micronuclei was 7-8 times folded and where more abundant in the same species of chicken according to the form collection. This increase in the formation of micronucleus indicates that feeding method and food contents causes clastogenic effects on peripheral erythrocytes of poultry chicken and might generate similar effects on the human population as consumers. Keywords: Genotoxicity, micronucleus, chicken, Clastogenic INTRODUCTION
M ATERIALS AND M ETHODS
Micronuclei are cytoplasmic chromatin-containing bodies that appears in the cell like a small satellite nucleus around the cell nucleus, due to chromosome fragments or entire chromosomes that are not incorporated in the main nucleus after cell division. The presence of micronuclei (MN) in cells is considered as a biomarker of damage to the DNA. The micronucleus test, is an in vivo and in vitro short-time screening cytogenetic test, introduced by Heddle [1 ] and Schmid [2 ] is a widely used method for assessing genotoxicity of chemicals in organisms [3 ]. The micronucleus test has been used because it is technically easy to master, reliable, least expensive and extremely rapid screening system for both clastogenic (agents that induce chromosomal breaks mainly through interaction with the DNA, to form of acentric fragments) and aneugenic (agents that induce chromosomal loss mainly through interference with the spindle apparatus) effects [4 ,5 ] . Clastogenic and aneugenic agents affect the spindle apparatus, which can be differentiated on basis of the relative induced micronucleus sizes or with the p resence of kinetochores [4 ,6 ,8 ]. The micronucleus test has been well established in several systems i.e. ovary, bone marrow, epithelial tissue, peripheral blood, liver, exfoliated buccal cells and fetus cells of several laboratory animals or human [9 ,1 4 ]. Micronuclei formation occurred in any dividing tissue of any species [4 ,1 5 ]. Micronucleus test was used to investigate environmental pollution in plants [1 6 ], fish [1 7 ], birds [1 8 ] and frogs [1 9 ,2 0 ]. This study aimed to investigate the clastogenic effects of chicken food storage using the micronucleus erythrocyte (MNE) frequency in the peripheral blood of chicken.
A nimals: Chicken weighing 1000-1200g were purchased alive from four different poultry farm (five chicken from each farm) located at Asser region, and five chicken were collected from the rural environment (village) and used as a positive control. The positive control group was feeding on natural food, while the other four groups were feeding on the food produced by Animal Food Factory located at Asser Region. Animals slaughtered at the same day and venous blood was collected from each chicken in a tubes containing 4:1 heparin: distilled water. Slide Preparation and Staining: For each chicken, five microscopic slides were prepared. Clean slides were taken and fresh blood samples from each chicken were smeared onto the slides for experimental as well as control group. The slides were air dried for 1-2 h and then fixed in absolute methanol for 10 min. After fixing, the same slides were stained in aqueous Giemsa (5%) for about 10 min [2 1 ]. Examination of Slides: Five chicken were used for each sample and control; 10,000 cells/chicken were analyzed, totaling 50,000 erythrocytes/sample. The frequencies of micronuclei in erythrocytes were detected under a Binocular microscope (OLYMPUS) using a 1000× oil-immersion lens. Only cells with intact cellular and nuclear membranes were scored. The following criteria was used as described by previous studies: (i) micronuclei should be one-tenth and onethird diameter of the main nucleus, (ii) they should be on the same plane of focus, (iii) they should have the
Corresponding Author: Kamel Saleh, Department of Biological Sciences, Faculty of Science, King Khalid University, 61413Abha, P.O.Box 9004, Saudi Arabia. 1646
J. Appl. Sci. Res., 3(12): 1646-1649, 2007 same color, texture and refraction as the main nucleus, (iv) they should be clearly separated from the main nucleus. Statistical Analysis: To determine whether the micronucleus frequency within erythrocyte of farm chicken was significantly different from the frequency within erythrocytes of normal living chicken, a one tailed single factor analysis of variance (ANOVA) was used. P value of < 0.05 were considered to indicate statistical significance. All the results were expressed as mean± SD for five chickens in each group. RESULTS AND DISCUSSIONS This preliminary study of the clastogenic effect of chicken food using micronucleus revealed that there is a significant induction of micronucleus in farm chicken. A comparison of micronucleus count (per 2,000 RBC's) was made between samples from different farms in Abha city (Asser region) and samples from chicken feeding on natural food (control). Chickens from different farms had significantly more micronucleated RBC's than the control. However, it is interesting to note that the level of micronucleus varied between different farms. Micronucleated RBC's summary data are presented in Table 1. Micronuclei formation also showed variation in their shapes and the number per cell as shown in Table 1 and Fig. 1. The micronucleus type (A) was found in all groups, while, type (B) and (D) micronucleus were found abundantly in farm1 and farm 2 (Fig. 2). The M NE frequencies in red blood cells obtained from all farm chicken were about 7-8 folds higher than the control (28.4±2.6 vs. 3.4±2.7 respectively, p
