مریم انصاری لاری

In the present study, aflatoxin M1 (AFM1) in bulk milk (n=72) and aflatoxin B1 (AFB1) in concurrent rations (TMRs; n=48) and feed ingredients (n=230) were assessed in 12 dairy farms in winter and summer. Bulk milk was sampled on days 1, 15 and 30 of the study. Feeds were sampled at days 1 and 30. Aflatoxin was measured using ELISA kits (detection ranges: 1-81 ngkg−1 for milk, 1.25-101.25 ngkg−1 for feeds). AFM1 was identified in all milk samples (range: 2.03 to >81 ngkg−1; median: 70 ngkg−1). Overall, 76% of milk samples (n=55/72) had AFM1 levels <81 ngkg−1 (Iranian limit:100 ngkg-1). Contaminations >81 ngkg−1 (n=17/72; 24%) were more frequent in winter (n=15/36 vs. 2/36). Sixty-nine percent of winter (n=25/36) and 31% of summer samples (n=11/36) had contaminations above the median. The chance of contaminations above the median was higher in winter (OR=5.33, P=0.007). All TMRs and ingredients had higher contaminations in summer. Seventy percent of summer and 30% of winter TMRs had contaminations above median (716 ngkg-1). The chance of TMR contamination above median was higher in summer (OR=5.57, P=0.002). The lower AFM1 levels in summer could be due to reduced hepatic AFB1 metabolism and lower dry matter intake induced by heat stress. Grain mix (rs=0.90; P=0.001), corn silage (rs=0.66; P=0.001) and wet beet pulp (rs=0.68; P=0.005) were the most prominent contaminants of TMRs. Due to the limitations of the diagnostic kit and different year-round nutritional conditions, higher or lower AFM1 contaminations are probable. With the current nutritional practices, higher summer contamination may happen if heat stress is efficiently controlled.

The subclinical mastitis can cause economical loss, therefore, access to the methods of prevention, control and reduction of mastitis, especially subclinical form, is so important and valuable. The aim of this study was to investigate the changes of adenosine deaminase enzyme activity in the cow milk with subclinical mastitis. Forty-six cows with subclinical mastitis that have taken positive results in the California mastitis test (CMT), without signs of illness, were considered as the treatment group. Ten cows that have taken negative results in the CMT, were considered as milk samples control group. Fat and protein levels of milk were measured as well as somatic cells count. Adenosines deaminases enzyme activities were also measured. The comparison of fat and protein in milk samples demonstrated no significant difference between healthy group, and the one with subclinical mastitis. The number of somatic cells in the cows with subclinical mastitis was significantly more than the control group. In the cows with subclinical mastitis, adenosine deaminase enzyme activity was significantly higher than the healthy cows. In general, adenosine deaminase enzyme activity can be used as a marker in diagnosis of subclinical mastitis.

Methyl tertiary-butyl ether (MTBE) is used to reduce carbon monoxide and ozone in urban air and to boost fuel octane. There is a lack of knowledge in the literature about the histomorphometric changes of the testis following exposure to MTBE. Therefore، this experimental study was performed to determine the effect of oral exposure to MTBE on histologic and histomorphometric changes of testis in adult rat. A total of 25 adult male Sprague-Dawley rats were randomly divided into five equal experimental groups: control، almond oil and three treatment groups which received 400، 800 and 1600 mg/kg/day MTBE in almond oil by gavages for 30 consecutive days. Histomorphometric analysis showed no significant difference in absolute and relative testis weight، connective tissue thickness، germinal epithelium height، tunica albuginea thickness and Sertoli cell numbers between experimental groups (P>0. 05). However، trend analysis showed that the seminiferous tubule diameter increased and interstitial cell numbers as well as spermatocyte and spermatid cell numbers decreased significantly in MTBE treated groups (P<0. 05). It may be concluded that MTBEcould exert adverse effects on spermatogenic cells in adult rat. Whether the observed changes in the present study are due to the direct effect of MTBE via passing blood-testis barrier or its indirect effect through another mechanism should be elucidated in future studies.

Normal bone structure is formed in childhood and adolescence. Any problem of bone formation at these stages will lead to significant osteoporosis and its complications in adulthood. Genetic factors are the most important factors in skeletal development. This study aimed to evaluate the bone mineral density and it's interfering factors in Iranian girls of Kawar of Fars.

In this cross sectional study 235 healthy girls of Kawar of Fars aged 9-18 years old participated and they underwent Dual-energy X-ray Absorptiometry (DXA) scanning of lumbar spine, femoral neck and total body. The LMS method was applied to calculate smoothed BMC, BMD and BMAD for age related centiles.

Maximum accretion of BMC and BMD was at ages of 11 to 13 and according to 3rd, 25th, 50th, 75th and 97th percentile, BMC and BMD of all sites were increasing with a rather fixed rate up to the age of 15 and then after it increased very slowly.

This study is the first study for normative data of BMC and BMD of Iranian girls and showed that BMC accretion of these girls was slower, but BMD accretion was greater than the girls of the other parts of the world. Absolute amount of bone mineral content in Iranian girls was lower than Indian, Lebanese and Asian girls of USA. Also weight and puberty were the two most important factors efficacious on BMD of the Iranian girls (of Kawar). Further research to evaluate the evolution of bone mineral density in Iranian children and adolescents is needed to identify the reasons for the significant differences in bone density values between our Iranian population and their Asian counterparts.

The objective of this study was to find a relationship between blood gas parameters and thyroid hormone activity with ascites syndrome in broiler chickens exposed to cold temperature and receiving a high quality diet. One hundred and sixty one-day-old broiler chicks were randomly divided in two equal groups. To increase the incidence of ascites, chicks of group 1 were fed ad libitum with a higher condensed diet and reared under a lower ambient temperature. Weekly, blood gas parameters and thyroid hormone levels were measured and growth performance was recorded. The hearts of dead and slaughtered birds were examined for determination of arterial pressure index (API) values. Ascites incidence was clearly higher in cold-exposing chickens compared with normal rearing chickens. The mean values of carbon dioxide tension of group 1 chickens were significantly higher compared with group 2 chickens at the 4th and 5th weeks of age, while the phenomenon of oxygen was reversed in these two experimental groups. The function of thyroid hormone levels were changed at week 4 of age, as observed for blood gas parameters. In conclusion, the present study showed a significant association between thyroid hormones functions, the levels of venous blood carbon dioxide and oxygen pressures in the two groups of chickens.

Unsaturated fatty acids such as turpentine oil can decrease serum leptin level with attention to this effect and the axial role of thyroid hormones and leptin in metabolism, the aim of the present study was to investigate the impact of dietary wild pistachio oil on serum leptin concentration and its relationship with thyroid hormones in experimental hyperthyroidism in Sprague Dawely female rat. 30 healthy adult female rats was selected and divided into five groups. Animals were fed with normal diet, levothyroxine plus normal diet, and 5, 10, 20 percent of turpentine oil plus normal diet respectively. Duration of the study was one month sampling obtained in each ten day intervals. Hyperthyroidism was created in animals with dosage of 12 mg/l of levothyroxine in drinking water for one month. Rats treated with 5%, 10% and 20% concentrations of wild pistachio oil for one month. Blood samples were collected from heart in each ten days interval. No difference was observed in thyroid hormones and leptin in control group (P>0.05). With an increasing in turpentine oil in diet a significant reduction was obtained for T4, T3 and fT4 respectively (P<0.05). A significant decrease also was observed with increase of 10 and 20 percent of turpentine oil in serum leptin level as compared to control group (P<0.05). There is a clear relationship between percent of turpentine oil feeding and thyroid and leptin hormone levels in experimental hyperthyroidism rats (P<0.05). Wild pistachio oil had been positive impression on reducing hyperthyroidism effects especially T4 concentration (P<0.05). Wild pistachio oil usage in the hyperthyroidismic rats caused to decrease significantly the serum concentration of leptin during the experimental period (P<0.05). There is a clear relationship between percent of turpentine oil feeding and thyroid and leptin hormone levels in experimental hyperthyroidism rats. Therefore, this study indicates that consumption of turpentine oil could induce the renovation of hyperthyroidism from regulation of leptin secretion and metabolism.

Fasciolosis is a cosmopolitan parasitic disease with considerable economic and public health importance. Fasciola hepatica is the major cause of fasciolosis in man and domestic animals. Although remarkable research works have been done around the optimum temperature and time required for miracidial development، little is known about the exact susceptibility of Fasciola hepatica eggs to high temperatures. In the present study، Fasciola hepatica eggs were initially incubated at 40°C، 45°C، and 50°C for various times (1، 2، 3، 4 and 5 h)، followed by incubation at 28°C for 16 days. Miracidial formation was subsequently investigated on the 16th day of incubation. Even though the rate of miracidial formation in the control group was 52%، in the eggs incubated at 40°C for 1، 3، and 5 h، the miracidial formations were 51. 4%، 42. 4% and 39. 9%، respectively، and these values in the group incubated at 45°C were 46%، 42. 5% and 33. 7%، as well. However، in the case of incubation at 50°C for 1، 2، 3، 4 and 5 h، these values were recorded as 1. 96%، 0. 57%، 0. 07%، 0. 00% and 0. 00%، respectively. The results indicated that the eggs were susceptible to high temperatures and incubation of the eggs at 50°C for 4 h was enough to significantly inactivate the eggs and prevent miracidial formation (P<0. 001). However، using the livestock faeces as fertilizer in many rural areas may lead to the contamination of pasture. According to the findings of this study، in the areas with a high prevalence rate of Fasciola hepatica، manure storage for a sufficient time or heating the livestock manure before use as fertilizer is strongly recommended.

High frequency waves are widely used in telecommunication and cooking. The biological effects of microwaves are in great attention. It is supposed that microwaves may increase the risk of hematological problems and the age at exposure may play an important role in this process. In this study, we evaluated the hematological parameters in rats by exposing them to microwave radiation at pre and post pubertal stages. In this study, 18 adult (2 months old) and 18 immature (1 month old) male rats were involved and each group was randomly divided into two groups; the test and the control group. The rats in the test group were exposed to 2450 MHz microwaves produced by a microwave oven three times a day for 30 minutes at each time. Control groups were kept in laboratory at the same temperature and light condition. After 60 days, blood samples were taken by heart puncture and hematological parameters including Hb, MCHC, MCV, RBC and WBC counts and total number of platelets were measured. The means of hematological parameters were compared by T-test and P<0/05 considered to be was significant. The results showed a significant decrease in Hb, MCHC, WBC and lymphocyte count in immature group compare to control group; while MCV, RBC and platelet count increased (p<0.05). The RBC count increased significantly in mature group compare to control group (p<0.05). Exposure to microwaves leakage of microwave oven significantly affected hematological parameters in immature rats while changes in matures was limited to RBC count. This effect maybe due to direct effect of microwaves on bone marrow or peripheral blood cells.

The aim of the present study was to determine the relationship between histopathological lesions and tissue enzymes in chickens affected by Marek's disease.Five apparently healthy chickens(as control group)and 25 chickens affected by Marek's disease were selected. After consideration of history and gross lesions, tissue samples were collected from kidney, liver, heart, ovary, pectoral muscle, spleen, crop, proventriculus and bursa of fabricius for histopathological and tissue enzyme studies. In tissue samples, the activity of aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), creatine kinase (CK), superoxide dismutase (SOD)and glutathione peroxidase (GPX)was measured. Histopathologically, lymphomatous lesions in visceral organs were included in local or diffuse ple omorphic small to medium lymphocytes, lymphoblasts,marek cells and rarely plasma cells. The results indicated that the activities of AST, LDH, CK, SOD and GPX were decreased in the crop of affected chickens. The activities of CK, LDH and AST in the liver tumors and the activities of LDH, AST, ALP, SOD, CK and GPX in pectoral muscles were increased. In proventriculus, the activities of AST, ALP, LDH and SOD were shown to be increased,but the activity of CK was decreased. The activities of AST and SOD in the ovary lesions and the activities of SOD, AST, CK and LDH in the heart lesions showed an increase. Fluctuations in the activity of enzymes in different tissues showed that measurement of these enzymes can not be used as a tumor marker in the diagnosis of Marek's disease.