JOURNAL OF VETERINARY RESEARCH
Year:2003 | Volume:58 | Issue:4|Papers Count:21

Objective: To evaluate the eletrocardiographic changes in the experimentally induced ascites in broiler chicks using T3 model. Design: Comparative study. Animals: A total of 150 one- day- old male cockerels from Ross breed. Procedure: Chicks were randomly divided into two equal groups (control and test). Chicks were reared for six weeks. T3 (1.5 ppm) was added to the diet of the test group from the 6th day of rearing period to the end of 6th week. At the end of each week, 5 chicks from each group were selected and electrocardiographic recordings were performed. Statistical analysis: Student's "t" test and Analysis of Variance. Results: There were significant elevation of the amplitude of R and S waves at the end of the 3rd and 6th weeks (for R waves), 2nd and 6th weeks (for S waves) in the test group in the leads III, aVF and aVR. The amplitude of both of these waves were elevated significantly in the test group, when they were considered as total means of weeks. There were significant elevations of the amplitude of R waves at the end of 6th compared with the other weeks in all 3 leads and the amplitude of S waves at the end of 6thweek compared with the 5th in the lead Ill. There were no significant changes in the direction of MEA. Conclusion: Recorded electrocardiograms can be used effectively to evaluate the likelihood of development of ascites syndrome in broiler chickens. The increase in the amplitude of R and S waves could be considered as the sign of ventricular hypertrophy.      

Objective: To estimate the normal values of serum lipids and lipoproteins and their correlations with thyroid hormones in clinically healthy male and female Lori-Bakhtiari sheep. Design: Descriptive study (correlation type). Animals: A total of 118 Lori-Bakhtiari sheep. Procedure: Blood samples were collected from the jugular vein of 118 clinically healthy Lori-Bakhtiari sheep according to their age (<1, 1-2,2-3,3-4, and 4-5 years) and sex. In each serum sample the concentrations of cholesterol, triglyceride, total lipids, HDL-colesterol, LDL-cholesterol, VLDL-cholesterol, thyroxine (T4), triiodothyronine (T 3), T3 uptake and free thyroxine index (FTI) were measured by routine procedures. Statistical analysis: Data were analysed by analysis of variance (ANOVA), regression analysis and Duncan's multiple range test to detect significant differences among the means, using SPSS/PC software. All values were expressed as and standard error of mean (SEM). P<0.05 was considered as significant. Results: The concentrations of cholesterol, triglyceride, LDL-cholesterol, T4, T3, T3 uptake and FTI in the different age groups were significantly different (P<0.05). With an increase in the age of the animals there were significant increases in the concentrations of cholesterol (P<0.05; r = 0.24) and LDL-cholesterol (P<0.05; r=0.20). The concentrations of cholesterol, total lipid, HDL-cholesterol, LDL-cholesterol, T4 and FT! were higher in females as compared with males (P<0.05). In contrast, the concentrations of triglyceride and VLDL - cholesterol were higher in male animals as compared to females (P<0.05). There were no significant correlations between thyroid hormones (T3 and T4) and serum cholesterol, triglyceride, total lipids and lipoproteins (HDL, LDL and VLDL). Conclusion: The results of this study indicate that in Lori – Bakhtiari sheep, there were no correlations among thyroid hormones and lipids and lipoproteins probably due to specific lipids metabolism in ruminants.      

Objective: Determination of reference values of serum proteins in Khuzestan indigenous buffaloes. Animals: A total of 154 apparently healthy mature and immature buffaloes including both sexes. Procedure: Blood samples were taken from Jagular vein. Total serum protein and protein fractions were determined by biuret and agarose gel electrophoresis, respectively. Statistical analysis: Two ways ANOVA and the least significant difference test were used to compare mean values of different proteins of male and female, mature and immature buffaloes. Also the student Hest was used to compare mean serum protein values between mature and immature buffaloes in both sexes. The regression analysis was used to compare the effect of age and sex on protein percentage between male and female, mature and immature buffaloes. Results: In this study 4 main serum proteins as albumin, α, β and γ-globulin were separated. γ -globulin mean value in females was higher than males. β and γ -globulin mean values in mature buffaloes were higher than immatures and α-globulin mean value in immatures was significantly higher than matures. In mature males α-globulin mean value was significantly lower than immature. Total globulin, βand β- globulin in mature females were significantly higher than immatures and α-globulin and albumin in immature females were significantly higher than matures. α-globulin and total globulin in mature females were higher than mature and immature males. Conclusion: Blood serum proteins of Khuzestan indigenous buffaloes consist of 4 fractions as albumin, α, β and γ-globulins. The variable age effect on proteins significantly and with increasing age β and γ-globulin mean values increased but albumin and α-globulin mean values decreased. The variable sex just effected on γ-globulin mean value in females and was higher than males.      

Objective: Macroscopic study of different regions of one-humped camel eyes. Design: Descriptive study. Animals: Six pairs of eyes of six mature camel. Procedure: Camel eyes were provided from Semnan slaughterhouse, fixed in 10% fomalin, dissected and studied. The layers of eye were studied by stereornicroscope. The cornea, lens and pupil were measured. Result: The cillia of upper eyelid are longer than lower eyelid in camel. There are many tactile hairs up the medial cantus of eye in the camel. The motion of upper eyelid is more than lower eyelid. Mean six of internal axis to external axis in cornea is around 2.92 in right and 2.93 in left eye. Mean six of dorsoventral axis of cornea is 2 in right eye and 1.95 in left eye of camel. All measurements are shown in tables. Conclusion: There are adipose tissue in the ventral, ventromedial and dorsomedial aspects of eyeball. This adipose tissue is cause of easy motioq. of third eyelid on the cornea of eyes. The cornea and pupil of camel eye are oval shape, but the medial poles are wider. The iris has a few folds in the dorsal and ventral borders. The folds of dorsal border of iris are greater. These folds are absent in other ruminant such as cattle. The tapetum is absent in the camel eye.      

Objective: Evaluation of an ELISA test using the cellular schizont antigen for the diagnosis of Theileria anulata infection. Design: Descriptive study. Animals: A total of 124 cattle, 56 cases with clinical features and 68 samples without clinical features and apparently healthy. Procedure: Serum was collected from cattle for the detection of anti-Theileria antibadies by indirect ELISA, using the cellular schizont antigen and the microplates coated with this antigen. On the blood-smears from the same cases, microscopic observation was done for determine the percentage of positive and negative cases of Theileria infection. Statistical analysis: Descriptive statistics. Results: Out of 56 serum samples, belong to animals with clinical features, 42 cases (75%) were ELISA-Positive and the rest (25%) were ELISA-negative whereas, all of them had positive bloodsmears. Also, out of 68 serum from apparently healthy animals, 19 cases (27.9%) were ELISA-positive and 15 cases (22%) were blood smear-positive. Conclusion: The present study by using of cellular schizont as solid phase antigen, showed high quality for detection of anti-Theileria antibodies by ELISA, and this test could detect 54 cases (76%) from a total of 71 animals with Thieleria-positive blood-smears. The results showed good correlation (80% coincidence between the data obtained by two methods. Therefore, the ELISA could be recommended as a screening test for detecting of Theileria infection in cattle.      

Objectives: To determine the time of appearance and persistence of Toxoplasma gondii in the blood of experimentally infected rat and evaluation of the possibility of early diagnosis of toxoplasmosis in rat blood samples by PCR. Design: Experimental study. Animals: Five healthy rats and ten Toxoplasma gondii infected rats. Procedure: Ten rats were infected experimentaly with Toxoplasma gondii tachyzoites (RH strain) intraperitonealy. As control, 5 toxoplasma free healthy rats were used. Blood was taken from the infected as well as uninfected rats 24 hour intervals for 30 days. Following DNA extraction from blood samples, amplification of DNA of the parasite was done by PCR method, using high sensitive and specific designed primers SDKF and SDKR. Results: Toxoplasma gondii DNA was identified in the blood of rats, 48 hours post infection. The DNA was persist in the blood for 16 days then become undetectable. Implications: SDKF and SDKR are sensitive and specific primers which can be used for detection of early infection of Toxoplasma gondii (RH strain) in rat.      

Objective: To survey on parasites of three barboid fishes from Tajan, and Zarem-roud Rivers in Mazandaran province. Design: Descriptive study. Animals: A total of 162 specimens of Barbus mursa, B.lacerta and B.capito. Procedure: Random sampling out was carried during September 2001 to August 2002 from four different stations of Tajan and Zarem-roud Rivers. The fishes were transported alive to the laboratory where they were killed by transsection of spinal cord and then were examined for different parasites. The infected organs were fixed in formalin and stained by Haematoxilin-Eosin. Statistical analysis: Descriptive statisites. Results: The following parasites were detected: From B.mursa: Myxobolus azerbajdzanicus from primary filaments, M.kovali from secondary filaments, M.squamae from skin of head, M.tauricus from fins, M.rutili from secondary filaments and M.osmaniae from intestinal wall. B.lacerta was infected by M. valdogeli in the secondary filaments and B.capito was infected in the muscles by M.musculi. Discussion: In southern part of the Caspian Sea Fauna Regions till now all together 20 different Myxobolus species were recorded. According to the results of this study Barbus mursa was revealed as a new host for 6 different Myxobolus species: Mazerbajdzanicus, M.kovali, M.squamae, M.tauricus, M.rutili and M.osmaniae.      

Objective: To determine the characteristic features of the cuticle and its supplements in Trichostrongylidae in Iran. Design: Descriptive study. Material and Methods: The samples including Trichostrongylus probolurus, Nematodirus abnormalis, Nematodirella, Haemonchus contortus, Marshallagia marshalli and Comelostrongylus mentulatus were collected from digestive systems of the ruminants in Iran. Sections were prepared and studied by means of light microscope. Results: In this study cuticle and its supplements including cephalic inflation, the spine at the female's end, deirid, synlophe (its length, number and decoration of ridges) and thickness of the cuticle were compared in letween different species. - Cephalic inflation and the spine are present in Nabnormalis and Nematodirella. - Deirids are present in H.contortus, M.marshalli and C.mentulatus. In H.contortus they are closer to the anterior end than two other species. - Synlophe is present in all species except T.probolurus. Synlophe begins from anterior part of the worm and ends just before the vulva in Nabnormalis and Nematodirella. In H.contortus it ends at midbody while it continues up to the posterior end of the body in M.marshalli and C.mentulatus. The number of the ridges from the beginning to the end of the synlophe is decreased in Nabnormalis, while they are increased in Nematodirella. There are at most 29 ridges in both of them. In H.contortus, M.marshalli and C.mentulatus they are increased in anterior half of the synlophe, then decreased in posterior half of the synlophe. The maximum number of ridges in H.contortus, M.marshalli and C.mentolatus are 36, 46 and 42, respectively. Conclusion: In general, presence of synlophe, its length, the number of ridges and their decoration on the cuticle are highly variable in Trichostrongylidae nematodes, so that they can be used as taxonomic criteria at the level of species.    

Objectives: 1) Comparative investigation of normal, partially infected and moldy breads to aflatoxin and their causative agents, 2) Determination of amounts and types of aflatoxin and Aspergillus spp 3) Detennination of total fungal counts in either breads containing aflatoxin or without aflatoxin, 4) Correlations between aflatoxin, Aspergillus and total fungal count. Design: Observational study. Procedure: 222 bread samples which consumed as ruminants foodstuffs were collected from bread shops in Urmia during 2001-2002. The number of normal, partially infected and moldy breads were 54, 56 and 112, respectively. Aflatoxins (AF) were assessed by Thin Layer Chromatography Method using standard aflatoxins BI, B2, GI, G2. Breads were cultured for Aspergillus spp using Saboroud Dextrose Agar Media and total fungal counts were calculated using dilution and culture method. Statistical analysis: Chi-square test and correlations coefficient. Resnlts: Aflatoxin was found in 42 (18.17%) breads in which 4 had 2 types of aflatoxin (1.8%) and in one bread 3 (0.5%) and another 4 types of aflatoxin (0.5%). Distribution and percent of aflatoxin B 1, aflatoxin B2, aflatoxin GI and aflatoxin G2 were 16 (36.67%.), 18 (42.87%), 7 (16.6%) and 10 (247%), respectively. 10 of 42 breads had aflatoxin Blover 20 ppm (4.5%),8 had 10-19 ppm (3.6%) and 24 had less then 10 ppm (10.8%). The percentage of aflatoxin contamination in normal, partially infected and moldy bread were 5.5%, 10.9% and 32.4%., respectively, which were significantly different (P<0.05). The results of fungal culture showed 94.1 % (80/85) infected to A. fumigatus (50 cases), A. niger (56 cases) and A.flavus (2 cases). 53 cases (63.357%) had A.fumigatus or A. niger, 26 cases (31.18%) showed two types of Aspergillus and one case had all three Aspergilluses. 10 of 80 cases were diagnosed in apparently normal and partially infected bread while 70 cases were in moldy breads. Aflatoxins were found in 42 of 85 cultured cases while 43 cases had no aflatoxins. Also 38 samples showed either aflatoxin, Aspergillus or total fungal count while in 41 cases instead of positive total fungal count and Aspergllus, no aflatoxin was detected. Total fungal count varied from 1 to 450000 fungi colony per gram bread. Positive correlations were found between aflatoxin and fungal count (r = 0.44), aflatoxin and A. niger (r = 0.58), aflatoxin and A. fumigatus (r = 0.85), total fungal count and (r = 0.90), total fungal count and (r = 0.70). Clinical implications: It is concluded that 1) aflatoxins produced by Aspergillus in nonnal and moldy breads could be an important as ruminant foodstuffs, 2) aflatoxin B1with over 20 ppm was found as a main aflatoxin in breads, 3) A.fumigatus, A. niger and A. flavus were the main Aspergillus strains in Urmia, and finally 4) It is recommended to modify the collecting and consumption methods of bread as ruminant foodstuffs to minimize the transmission of aflatoxin to ruminants and human as well.      

Objective: To compare the effects of different diluents with levels of 13 and 7% glycerol on motility of buffalo spermatozoa (pre-and post- freezing and thawing). Samples: Comparative experimental study. Animals: Twelve ejaculates of2 buffalo bulls (4.5 and 6 years old). Procedure: Semen samples with initially very good and excellent quality (motility 4 and 5) were selected and immediately evaluated for motility. Then, aliquots of each semen sample were subjected to dilution, cooling, equilibration, freezing and thawing as follow: Experiment 1. Phosphate and citrate extenders with 13 and 7% glycerol were used. Experiment 2. Glucose and cysteine were added in the same extenders and were compared to the effects of tris extender on motility of buffalo spermatozoa. Statistical analysis: Descriptive statistics. Results: The motility of spermatozoa maintained up to a limited time of storage in phosphate and citrate extenders with low level of glycerol and beyond of this storage time (after equilibration and thawing) the motile life of spermatozoa deteriorates quickly. Ttis diluent proved to be superior in maintaining the motility of spermatozoa. Also, the sperm motility and recovery rate were higher in the semen extended in tris diluent with 13% glycerol as compared to those extended with 7% glycerol (70 and 87.5% versus 52 and 65%). Clinical implications: Based of our findings, we suggest the use of tris diluent with 13% glycerol for the cryopreservation of buffalo bull spermatozoa.      

Objective: In this study, the pathologic effects of methenamin in broiler chickens were studied. Design: Experimental study. Procedure: For these purposes 150 day-old broiler chickens of Arian breed were randomly divided into six equal groups as follows. group I: no use of met hen amine (control), group II: Daily use of 1: 1000 methenamine in drinking water continuously for 8 weeks. group III: Daily use of 2:1000 methenamine in drinking water continiously for 8 weeks, group IV: use of 1:1000 methenamine in drinking water for one week of the end of rearing period, group V: Daily use of 4: 1000 methenamine in drinking water continuously for 8 weeks, group VI: use of 2: 1000 methenamine in water for one week of the end of rearing period. All groups were reared in same condition and nutrition and housing except the administration of methenamine. At the end of rearing periods samples of liver and kidneys were taken for histopathologic study. Statistical analysis: Chi square test. Results: The microscopic lesions such as congestion, fatty change, locallymphocyte aggregation, focal heterophil aggregation were observed, in liver and in kidney, congestion, cell swelling, acute tubular necrosis, focal lymphocytic aggregation and focal heterophil aggregation were diagnosed. No significant changes were seen in treatment and control groups by chi-square test (p<0.05). Conclusion: It is concluded that oral administration of methenamine has no significant pathologic effect even with high dose and long period (8 weeks) on liver and kidneys of broiler-chickens.      

Objective: To identify the clinical signs, clinical pathology and pathological findings in experimental Echium italicum poisoning in native calves. Design: Interventional study. Animals: Ten native calves aged 5 to 7 months in two groups (experiment and control). Procedure: The fresh E. italicum was fed as the sole diet to experimental calves during 8 weeks. Calcium, phosphorus, sodium, creatinine, BUN, AST and GGT were determined in serum of calves at weekly intervals during the period of experiment. Histopathological examinations were performed on tissue samples. Statistical analysis: One way ANOVA. Results: This experimental study revealed a significant increase in serum calcium, GGT and AST (P<0.05). During the trial, one of the 5 calves on the Echium diet died in day 49 without showing any symptoms before. The calves of experimental group showed similar histological changes in liver, such as centrilobular necrosis, portal triad fibrosis and bile duct proliferation with polymorph neutrophil infiltration. In the asymptomatic calf, the kidneys showed acute tubular necrosis. Clinical implications: It is concluded that E. italicum is not a suitable fodder for calves and can be toxic due to its pyrrolizidine alkaloids.      

Objective: Assessment of camel sperm motility obtained from cauda epididymis in Green buffer with or without 20% egg yolk. Design: Descriptive study. Samples: Testicles from Dromedary camel. Procedure: Dromedary camel testicles (n=100) were obtained from slaughter-house, cauda were incised in the laboratory. The sperm cells were transferred into Green Buffer medium and sperm motility was assessed. Statistical analysis: Descriptive statistics, χ2-test. Results: No motility was observed in epididymal sperm obtained from testicles transported in warm saline, however, transportation of testicles in 4-5°C supported sperm motility by 80%. After incubation, 5% of sperm cells from caput epididymis were motile. These values were 20%, 50% and 90% for caput-body, body-cauda and cauda regions respectively. No significant different was observed between motility of right and left testicles respectively. Approximately 80% of epididymal sperm cells from cauda epididymis were motile in Green buffer + 20% egg yolk after 1 hour incubation which was significantly higher (P<0.01) than sperm cells from corpus (30%) and caput (5%) epididymis. These values were 70%, 10% and 0 for cauda, corpus and caput epididymis in 2nd hour. Motility of caudal sperm cell were higher in Green buffer without egg yolk at first 2 hours of incubation but it decreased and remained lower during the observation. Conclusion: Dromedary camel epididymal sperm cells motility is supported by Green buffer.    

Objective: Report of a sertoli cell tumor. Animal: An eight-year-old intact male terrier. Procedure: On the basis of clinical signs, laboratory findings, radiographic, ultrasonographic, surgery of tumor, and histopathologic study diagnosis was confirmed. Results: In clinical examination a spherical, rum mass in caudal part of right hypogastric region was observed. Plain radiography survey showed a round radiopaque mass. Ultrasonography delineated an echogenic spherical mass. This mass and atrophied testicle was removed. Microscopically, the tumor consisted of masses of elongated, fusiform cells, with eosinophilic, vacuolated cytoplasm and round or ovoid pleomorphic nucleus. The neoplastic cells were arranged in a palisading pattern in which adjacent tumor cells laid parallel to one another with long axes perpendicular to basement membrane. Clinical implications: The mass on the basis of location, gross and histopathologic characteristics was diagnosed as sertoli cell tumor.      

Objective: Diagnosis causative agent of nodular lesions in gizzard. Design: Case report. Animals: Indigenous birds. Procedure: At necropsy of indigenous birds, nodular lesions in the gizzard together with helminths were observed. For parasitological examination, the isolated helminths were treated with lactophenol solution and for histopathological examination of the nodular lesions, tissue samples were stained with Haematoxilar and Eosin (H&E). Results: In parasitological examination of the isolated helminthes based upon morphological and size characteristics, the parasites were identified as Cheilospirura hamoulosa. In hislopathological examination of the nodular lesions, inflammatory reactions with infiltration of lymphocytes and macrophages were observed along with hyperplastic changes in the glandular region of gizzard Conclusion: Cheilospirura hamoulosa is able to produce nodula lesions in gizzard of indigenous birds.      

Objective: Comparing the efficacy of coccidiostat drugs, Diclazuril, Salinomycin, and Narasin on performance parameters of broiler chickens in experimental coccidial infection. Design: Completely randomized block. Animals: A total number of 300 male day-old Ross 208 broiler chickens. Procedure: The chicks were randomly divided to 5 groups of 60 birds (3 replicates/treatment), and placed in battery cages. The groups were: 1) which did not receive any coccidiostatic drug or oocysts (negative control), 2) which did not receive any coccidiostatic drug but was challenged with oocysts (positive control), 3) Dic1azuril, 4) Narasin, and 5) Salinomycin. Treatment groups received the related coccidiostats from the beginning of the rearing period up to 3 days before slaughter( 49 days of age). Birds in all groups (except group 1), were challenged with 105 of mixed inoculum of E. tenella, E. maxima, and E. acervulina. Eight days post-challenge, fecal samples were taken and oocysts per gram of feces determined for five consecutive days. By weighing the chicks and their consumed feed at 28 (before challenge), 35, 42 and 49 days (end of the rearing period), mean of body weight (BW), weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) of all groups determined weekly. Statistical analysis: Analysis of variance, Tukey's test.Results: At 35 days old (1 week after challenge), the differences among WGs of treated and positive control groups were significant (P< 0.01).  At the same age, there were not any significant differences among FCR of treated and negative control groups, but FCRs of all groups were significantly better than positive control (P<0.01). At 42 days of age, there were no significant differences among the performance of treatment groups (P>0.05). At 49 days old, FCR of Salinomycin was better than positive control (P< 0.05), but no significant differences observed among treatments(P>0.05). Diclazuril and Salinomycin significantly reduced the OPG in comparison with positive control (P< 0.001). Conclusion: According to the results of this study, using these coccidiostats can improve the performance parameters of broiler chickens and their usage can be recommended specially when coccidial infections may occur. Comparison the performance of treatment groups showed partial improvement of BW and FCR by Diclazuril and Salinomycin respectively. In addition these two coccidiostats reduced OPG significantly.      

Objective: The purpose of this study was to designing a simple, sensitive and cheep method based on dot ELISA system for detecting of seroconversion to infectious bovine rhinotracheitis virus (IBRV). Procedure: In the first step rabbit antibovine immunoglobins was conjugated with horseradish peroxidas and purifide IBR virus was used as coated antigen on nitrocellulose membrane. In order to standardization of the kit, 50 positive and 50 negative sera that tested by commercial ELISA kit (Svanova) and evaluated the best dilution o{the materials that used in the test. Results: The optimum dilution of different compound of the dot ELISA kit Was: 1:200 for HRPO conjugated antiglobulin, 1:8 for serum and 1 for tetramethylbenzidin as substrate. In order to evaluation of correlation of dot ELISA method with commercial ELISA kits, 488 serum samples were tested by two mentioned testes. Statistical analysis: Chi squire test. Conclusion: Dot ELISA has revealed 88/9% correlation with plate ELISA and no significant difference between results of these two tests.    

Objective: To compare histological changes of the vaginal wall during follicular and luteal phase of the oestrus cycle in river buffaloes. Design: Descriptive study. Animals: 30 specimens from cyclical buffaloes in the follicular and luteal phase. Procedures: Vaginal specimens were prepared and stained by the method of Hematoxylin - Eosine and three special methods of Verhoof, Toluidine blue and P.A.S. The number of cell layers; type of epithelial cells, vascular activities; distribution of plasma cells, elastic and collagen fibers in the mucosa and submucosa were studied. Statistical analysis: Data from buffaloes in follicular or luteal phase were compared using student "t" test, ANOVA, correlation coefficient and regression analysis. Results: Results of the present histological study indicated that during follicular phase, the epithelial cell structure was stratified cuboidal or squamous, which in some areas especially in the cranial part of vagina one layer of the columnar secretary cells was over the superficial layer of the epithelium. In addition, secretary activity of epithelial cells and blood vessels increased in the follicular phase, which was less active in the cranial part. In the luteal phase, epithelial structure was stratified cuboidal and squamous. There was significant increase in accumulation of lymphocytes, plasma cells and mast cells. This may increase the histological defense mechanism of the organ. Results of the present hystomorphometry study indicated that the thickness and the number of the cellular layers of the vaginal epithelium in the follicular phase, in three different parts of the vagina increased significantly (P<0.001) in comparison with those of the luteal phase. This increasing of thickness related more to the number of cellular layers than to the size of the cells. Clinical implications: Some differences was shown in the histological and histomorphometrical structure of the vaginal wall during the phases of the oestrus cycle in buffaloes, which may be used as a diagnostic method of the follicular and luteal phases in buffaloes.      

Objective: To assess the impact of sodium chloride, pH and acid type on destruction effect of microwave heating on Listeri monocytogenes biotype 4a in liquid medium. Design: Experimental study Procedure: Bacterial suspension (1.5× 107 CFU ml-1) in nutrient broth with different concentrations of sodium chloride (0.5, 1.5 and 3.0 percentage) was prepared at various pH values (4.5, 5.5 and 6.5) induced by hydrochloric acid, and acetic acid. The suspensions were irradiated with microwave at successive five- second intervals and bacterial colonies were counted with standard plate count method. Radiation was continued until the microbial count reached to zero. Each experiment was repeated three times Statistical analysis: One way ANOVA repeated measures. Results: Various concentrations of sodium chloride had no significant effect on destruction of Listeria monocytogenes by microwave heating (p>0.05). At pH=4.5, the destruction effect of microwave radiation was significantly greater than those at pH values of 5.5 and 6.5 (p<0.01). The destruction effect of microwave was not affected by acidulent type at pH=4.5 (p>0.05). Conclusion: Several factors affect both microwave heating and heat resistance of microorganisms. The effect of each factor such as sodium chloride may be affected by interactions among other factors, resulting in opposite effects of the considered factor. The present study shows that sodium chloride in liquid media at levels equal to those of food (0.5-3.0 percentage), had no significant effect on destruction of Listeria monocytogenes by microwave heating The heat sensitivity of bacteria increases by acidic condition Although the destruction effect of microwave radiation increased significantly at pH=4.5, it was not affected at pH levels equal to those of food (5.5 -6.5). At equal pH levels, organic acids increase the destruction effect of heat more than inorganic acids. At the present study, however, no significant difference was observed in liquid media containing acetic acid or hydrochloric acid at pH=4.5