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91.
The aim of the present study was to describe some of the oxidative stress parameters in bitches suffering from spontaneously occurring mammary gland tumours. The experiment involved 28 bitches which had mammary gland tumours removed surgically (15 bitches with malignant tumour and 13 with benign tumour) as well as 10 clinically healthy bitches. The activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were determined in haemolysates of erythrocytes derived from the animals. The concentrations of thiobarbituric acid reactive substances (TBARS), as well as -SH groups, were determined in blood plasma. GSH-Px activity was significantly higher in the malignant tumour group than in healthy animals. SOD activity was significantly higher in animals with tumours compared with the control group. Activities of both enzymes were higher in animals with malignant tumours than in benign groups, but the differences were not statistically significant. The concentrations of TBARS and -SH groups were similar in all examined groups. The increase of antioxidative enzyme activities in these animals may suggest the activation of antioxidative defence mechanisms in mammary gland carcinogenesis. Moreover, it might indicate the participation of oxidative stress in malignancies. Further experiments involving more animals, with more frequent sample collection and the use of other oxidative stress markers are necessary.  相似文献   
92.
Zearalenone is a mycotoxin widely occurring in cereals and animal feed, and it is associated with hyperestrogenism and other reprodutive disorders in animals. A new method of detoxication of feedstuffs involves alkaline hydrolysis of toxic macrolactone (1) (as well as model compounds (2a, 2b)). The method caused modification of zearalenone structure under mild conditions and the toxin underwent irreversible hydrolysis with high efficiency.  相似文献   
93.
The ILT case was observed in laying hen farm where birds of different age (from 40 to 107 weeks) were kept in 10 flocks. A rapid spread of the disease, the decrease in egg production (in flock No. 1 it reached 58%) and higher mortality (the highest in 76 and 77 week-old birds, accounting for 0.11% and 0.36%, respectively ) was recorded during first 2 weeks of disease. Antibodies against ILT virus were detected in serum of the examined birds during the whole observation period (50 weeks after the disease outbreak). The laying hens were vaccinated at 8 weeks of age and boosted after 5 weeks. The vaccine was applied in drinking water, in a dose twice as high as usually recommended per one bird. Immunopropylaxis efficiency was estimated on the basis of immunological response in birds (serum samples, ILT ELISA kit, Guildhay Ltd.) and general health status of hens in flocks. Postvaccinal immunity, the presence of specific antibodies against ILT, was observed in all birds during the observation period (51 weeks). During that time GMT value ranged from 8261,3 (week 10) to 5196 (week 51) after the second vaccination, and CV amounted in this period to 41.1% and 51%, respectively. Subsequently, clinical symptoms of the disease disappeared and the egg production, as well as mortality, returned to the level of technological norms for laying hens.  相似文献   
94.
The aim of the monitoring of zearalenone presence in the blood plasma of women with neoplastic lesions in the reproductive tract was to asses whether the phytosteride is noted in the patients blood and whether the correlation exists between its presence and the incidence of particular neoplasm. The presence of zearalenone or its metabolite--alpha-zearalenole, was noted in 13.51% of the examined women. In 60% of the patients with the confirmed presence of the xenobiotic it was noted in the lowest concentrations. These patients had neoplastic lesions of Carcinoma corpus uteri type.  相似文献   
95.
The aim of the study was to evaluate the influence of low dose (LOEL - lowest observed effect level) of zearalenone (200 microg/kg b.w.), applied per os for 7 days (short-term intoxication), on sexual behavior, concentration of the examined xenobiotic and its metabolite and selected estrogens in sexually immature gilts: ovariohysterectomised (group D1) and intact (group D2) animals. Clinical signs of oestrus (reddening, oedema and hyperaemia of the vulva and serorhoea from the reproductive tract--lack of standing reflex) were obserwed in group D1 on day 6 and in group D2 on day 4 of the experiment. Laboratory analyses of blood plasma were carried out determine the presence of zearalenone and alpha-zearalenole. They revealed an increase in the level of alpha-zearalenol before the oestrus, decrease in total amount of both examined substances on day when the oestrus appeared and increase in the level of both examined xenobiotics in the post oestrus period together with the higher share of zearalenone. Medium concentrations of estrone and estradiol within the borders of method determination in the majority of periods examined. Higher levels of estrone (32.0 pg/ml) were found on day 4, in the group D2 and estradiol (6.5 pg/ml) on day 6 in the D2 group. The presents study revealed that zearalenone applied per os at LOEL dose causes the incidence of apparent sexual readiness (without standing reflex) in sexually immature gilts with the somatically immature reproductive system.  相似文献   
96.
The aim of the study was to evaluate the occurrence of mycotic and protohecal mastitis in herds in south-eastern part of Poland. A total of 3091 milk samples from udder quarters with clinical and subclinical mastitis from 29 dairy herds was investigated in this survey. Milk samples were plated as soon as possible on blood agar (BA), Mac Conkey agar, aesculin-tallium acetate-crystal violet agar, and Sabouraud agar. A hundred and thirty one yeast (4.23%) and eleven Protoheca zopfii (0.35%) strains were isolated from cows with clinical and subclinical mastitis. All the isolated fungi were the yeast classified into 4 genera (Candida, Trichosporon, Saccharomyces and Rhodotorula). The most frequently isolated yeasts were Candida sp., C. kefyr, C. humicola, C. rugosa and C. inconspicua. Both fungi and algae were isolated first of all during a confinement-housing season.  相似文献   
97.
The content of iron, zinc, copper, manganese, lead, and cadmium was determined in the kidney, liver, and abdominal muscle of the brown hare (Lepus europaeus), a species known for its bioindicative potential in environmental quality assessment. The animals assayed were divided into immature (in their first year of life; n=25) and adult (n=39). The hares were acquired in an area situated far away from major cities and direct impacts of industrial and transport pollution. The zinc content found in the assayed hare's muscles (25.9 microg/g w.w.) and that of manganese in the kidneys, liver, and muscles (2, 2.51 i 0.85 microg/g w.w., respectively) tended to be higher than those reported from the brown hare elsewhere in Europe. The content of cadmium (particularly in the kidneys) and lead proved substantial and close to those typical of the hare inhabiting industry-affected areas. Analysis of the data pooled for all the individuals showed Zn and Cd contents to increase with age in the kidneys, the liver Cd content increasing with age as well; on the other hand, the age-Cu content was negative. In addition, a number of significant correlations between the metals themselves were revealed, particularly with respect to Zn-Cd correlation in kidneys (r(s)=0.47), Fe-Cd, Zn-Cu, Mn-Zn, Mn-Cu, and Mn-Pb in the liver (r(s) of 0.42, 0.86, 0.72, 0.79, and 0.42, respectively), and Zn-Cu in the muscle (r(s)=0.56). The kidney cadmium content was higher by 81% in the adult than in the immature hare, the adult hare muscle copper content being lower by 15.5%.  相似文献   
98.
Five-month-old male rates were exposed to 0.5 ppm ozone for 50 days, 5 hours a day. A week before the completion of ozone exposure, a biological test was performed to determine the fertilization rate and the survival rate of newborns in both ozone-exposed and control animals. After 50 days, the rats were sacrificed with an overdose of halotane, and testes were collected to assess the morphology and motility of spermatozoa. Neither the morphology of spermatozoa nor motility parameters determined by the CASA (computer-assisted sperm analysis) system showed statistically significant differences between ozone-exposed and control males. The number of successful matings and the survival rate of newborns per litter within one year postpartum were also similar in both groups. However, sperm concentration was by 17% lower in ozone-exposed rats, compared with the control animals.  相似文献   
99.
The nuclear male sterility gene ms8 is expected to facilitate the production of sweet pepper (Capsicum annuum L.) hybrids as it provides means for hybridization without the labor-intensive hand emasculation of female inbred lines. The development of molecular markers linked to ms8 locus will help the breeding practice for the selection of hybrid parental lines. In this study, F2 population resulting from a cross between the sweet pepper male sterile line 320 and the male fertile variety Elf was used to identify DNA markers linked to the ms8 locus. With the use of RAPD–BSA technique, seven markers linked to the ms8 locus were found. Four of them were converted into SCAR markers. In addition, two COSII/CAPS markers linked to the ms8 locus were identified. Comparative mapping with reference pepper maps indicated that the ms8 locus is located on the lower arm of the pepper chromosome P4. Identified markers are useful for molecular breeding, however, at present markers tightly linked to ms8 locus are still lacking. Identification of molecular markers linked to the ms8 locus and determination of its chromosomal localization are useful for fine mapping and also provide the perspective for ms8 gene cloning.  相似文献   
100.
Vaccines composed of either virulent or attenuated Eimeria spp. oocysts have been developed as an alternative to medication of feed with ionophore drugs or synthetic chemicals. The purpose of this study was to evaluate the use of gel-beads containing a mixture of Eimeria acervulina, Eimeria maxima, and Eimeria tenella oocysts as a vaccine against coccidiosis. Newly hatched chicks (Gallus gallus domesticus) were either sprayed with an aqueous suspension of Eimeria oocysts or were allowed to ingest feed containing Eimeria oocysts-incorporated gel-beads. Control day-old chicks were given an equivalent number of Eimeria oocysts (10(4) total) by oral gavage. After 3 days, chicks were randomly assigned to individual cages, and feces were collected between days 5 and 8 postinfection. All samples were processed for total Eimeria oocysts. At 4 wk of age, all chickens and a control nonimmunized group received a high-dose E acervulina, E maxima, and E. tenella challenge infection. Oocyst excretion by chicks fed gel-beads or inoculated by oral gavage was 10- to 100-fold greater than that of chicks spray-vaccinated with the Eimeria oocysts mixture (log 6.3-6.6 vs. log 4.8). Subsequent protection against challenge as measured by weight gain and feed conversion efficiency was significantly greater (P < 0.05) in gel-bead and oral gavage groups compared with spray-vaccinated or nonimmunized groups. Also, gel-bead and oral gavage groups showed no significant difference (P > 0.05) in weight gain and feed conversion efficiency compared with nonchallenged controls. These findings indicate that incorporation of Eimeria spp. oocysts in gel-beads may represent an effective way to deliver live oocyst vaccines to day-old chicks for preventing subsequent outbreaks of coccidiosis in the field.  相似文献   
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