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The main aim of this study was to evaluate the prevalence of campylobacteriosis in population of Polish heifers. An additional objective was to compare two independent methods used in diagnosis of the disease: culture and PCR. The 1,600 vaginal swabs from heifer origin from different farms of Poland were investigated using both methods. The results showed that the percentage of positive samples was 0.75% when the culture method was used, while the application of PCR method has shown 1.81% positive results.
Since January 2006, and in accordance with EU legislative procedures, the use of antibiotics as growth promotors in feedingstuff has been prohibited. Withdrawal of antibiotic growth promoters in an animal feeding has resulted in a search for new alternatives such as: prebiotics. At present prebiotics are used mostly for preventing and controlling the negative consequences appearing in the aftermath of the prohibition of antimicrobial applications as animal feed additives. The article presents the effect of prebiotics (mannan-oligosacharides, fructo-oligosaccharides, galacto-oligosaccharides) on humoral and cellular mechanisms of specific and non-specific immunity in livestock.
The aim of the study was to estimate the effect of tylosin and prebiotics (β-glucans and mannanooligosaccharides) added to feed on the phagocitc activity of polimorfonuclear leukocytes (PMNL) in calves. The study was performed on 36 clinically healthy, Black and White Lowland calves, aged 6-8 weeks. The animals were randomly divided into three equal groups. Calves in group I were fed a feedingstuff supplemented with tylosin. Group II received prebiotics, and group III (control) was fed the same feedingstuff without additives. The following phagocytic parameters were determined in the peripheral blood of the calves: phagocytic index (IF), the percentages of phagocytic (%kf) and NBT-positive cells, and the spontaneous migration of neutrophils (MG). The results showed that both prebiotics and tylosin caused a significant increase in the phagocytic activity of PMNL in the experimental groups. This was expressed by the higher values of the examined phagocytic parameters compared with the controls.
The objective of this study was to determine the effect of tylosin and prebiotics (β-glucans and mannanooligosaccharides) on fermentation processes, rumen microorganisms and production yield in calves. The study was performed on clinically healthy, Black and White Lowland breed calves, 36 aged 6-8 weeks and 120 aged 10-14 weeks, respectively. The calves were randomly divided into three equal groups. The calves in group I were fed with feedingstuff supplemented by the tylosin. The second group of calves received prebiotics and the control (group III) was fed the same feedingstuff without the additives. The rumen fluid samples were collected at one week intervals for seven weeks. The following parameters of the samples were determined: protozoa and bacteria count, as well as selected basic rumen metabolism parameters (pH, volatile fatty acids, fermentation of glucose, digestion of cellulose, reduction of nitrates). In the field trials on the older animals, production parameters such as the body weight gains, growth (GR) and feed conversion rates (FCR) were investigated. The significant changes in the rumen functions with different characteristics were noted in both experimental groups. The increase in the total number of bacteria and decrease in protozoa were observed in calves treated with prebiotics (Group II). In contrast, in calves that received tylosin (Group I) the parameters behaved in a reverse manner. The positive changes were also observed in the rumen metabolism during the prebiotic applications. A significant improvement in glucose fermentation, cellulose digestion and nitrite reduction was recorded. Moreover, a significant decrease of pH and increase of volatile fatty acid concentration in rumen fluid were observed. The opposite results were noted in the calves receiving tylosin. Additionally, the production parameters were higher in the calves than in the remaining animals; however, in all experimental calves more profitable values of growth rate (GR) and body weight gain were noted than in the controls. Overall, it appears that prebiotics can be a promising alternative for withdrawn antibiotic growth promoters.
The aim of the study was to estimate the effect of tylosin and prebiotics (β-glucans and mannanooligosaccharides) added to feed on the selected humoral immune parameters in calves. Among them, the concentrations of total protein and γ-globulin, titre of conglutinin, and activity of alkaline phosphatase were tested in calf serum. The study was performed on 36 clinically healthy, Black and White Lowland breed calves, aged 6-8 weeks. The animals were randomly divided into three equal groups. The calves in group I were fed with feedingstuff supplemented by the tylosin. The second group of calves received prebiotics and the control (group III) was fed the same feedingstuff without the additives. The results indicated that supplementation of feedingstuff with prebiotics and tylosin had a positive effect on the total protein and gammaglobulin concentrations. The titre of conglutynin was significantly higher in the group of calves fed prebiotics in comparison with the control group. The activity of alkaline phosphatase was higher in both experimental groups of animals but a stronger activity of this enzyme was observed in the calves fed tylosin.
The aim of the study was to evaluate the effectiveness of Q fever treatment with oxytetracycline based on the level of Coxiella burnetii antibodies in the sera of infected goats and cows, and excretion of Coxiella burnetii in milk. The study was performed in naturally infected goats and cattle. Forty-six goat sera and 35 cows' sera were investigated three times before, and twice after treatment with oxytetracycline. The percentage of seronegative goats after treatment (the third examination) was 86.96% while the percentage of seronegative cows after treatment was 52.77%. Moreover, the molecular studies (real-time PCR) of cheese from milk of these animals showed that the specific sequences of DNA for Coxiella burnetii were present despite treatment with oxytetracycline.
The aim of the study was to estimate the effect of tylosin and prebiotics added to feed on the blood morphology and general health condition of calves. The experiment consisted of two independent stages: laboratory examinations and a field trial to determine the general health condition of the animals. The first stage of the experiment involved 36 clinically healthy calves, aged 6-8 weeks, and lasted 7 weeks. During that period, blood samples were taken from the animals twice a week, and routine haematological indices i.e. RBC, HCT, MCV, HGB, MCH, MCHC, WBC, LYM, MID, PMNL, PTL and MPV - were determined. The results obtained in the first stage of the study showed a significant increase in the total number of leukocytes and some of their subsets, i.e. PMNL, and especially LYM and MID, in calves receiving prebiotics. Higher values of these indices were also noted in calves treated with tylosin. Distinct stimulating effects of both additives were also observed in some haematological parameters, such as RBC, HCT, HGB and PTL. In the field stage of the study the general health status of 120 calves was evaluated. The health status of the animals in experimental groups was satisfactory; on the other hand, a few control calves suffered from infectious respiratory problems, which had to be treated with antibiotics.
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