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101.
102.
The pathogenic mechanisms involved in tropical theileriosis, caused by the tick-borne protozoan parasite Theileria annulata, are unclear. Pathology is associated with the schizont stage of the parasite, which resides within bovine macrophages. Breed-specific differences in pathology have been observed in cattle, several Bos indicus breeds are relatively resistant to tropical theileriosis whilst Bos taurus cattle are highly susceptible. Infected cells express pro-inflammatory cytokines and it has been hypothesized that these cytokines play a major role in the pathology of the disease. Therefore, using quantitative RT-PCR we investigated the expression of the key candidates, interleukin 1 beta (IL-1beta), IL-6 and tumour necrosis factor alpha (TNF-alpha), in T. annulata low passage infected cell lines derived ex vivo from experimental infection of resistant and susceptible cattle. mRNA for each cytokine was detected in all cell lines investigated at levels higher than those observed in resting monocytes. However, the analyses did not identify any breed-specific differences. Therefore, these results are not consistent with the hypothesis that differential regulation of infected cell derived pro-inflammatory cytokines (IL-1beta, IL-6 and TNF-alpha) accounts for the breed-related differences in resistance and susceptibility to T. annulata infection. Other, currently unknown mechanisms may be of greater importance.  相似文献   
103.
The study was conducted on 10 buffalo calves with a weight of 98.5 +/- 3.9 kg and age 9.7 +/- 1.3 months. Ten trials of two treatments were carried out using a randomized block design. Atropine at the dose of 0.02 mg/kg bodyweight was administered in both the groups. The animals of group I received romifidine at the dose of 10 microg/kg i.v., 10 min after atropine administration, whereas, animals of group II received triflupromazine at the dose of 0.3 mg/kg i.m. and 10 min later romifidine at the dose of 10 microg/kg i.v. immediately followed by ketamine at the dose of 5 mg/kg i.v. The onset of action of romifidine in group I occurred within 2 min and the animals remained under mild sedation for 31 +/- 4.8 min. In group II, the triflupromazine-romifidine-ketamine combination induced anaesthesia for 14 +/- 2.3 min. Hypothermia, significant bradycardia and respiratory depression was noticed in both groups at different time intervals.  相似文献   
104.
Immunomodulation is a commonly used method of prophylaxis in humans and animals. Lysozyme dimer (KLP-602) was used at a dose of 50 ug/kg b.w. in order to correct the immunosuppression caused by the action of herbicide glyphosate (Roundup- Monsanto), which was used in a single bath for 10 minutes in a concentration of 100 mg/l of water. The investigations were carried out on 2 species of fish: the carp (Cyprinus carpio L.) and european catfish (Silurus glanis L.). Herbicide glyphosate caused a decrease in metabolic and phagocytic activity (RBA and PKA) and in proliferative response stimulated by Con A and LPS in carp and european catfish. The immunosuppression sustained for about 2 weeks. The results obtained indicate the possibility of correction of immunosuppression applying lysozyme dimmer (KLP-602) after use of which, the level of the studied indexes increased.  相似文献   
105.
Different barley varieties, consisting of hulled and hull-less types, of normal, waxy, and high amylose starch, as well as two-rowed and six-rowed types, were analyzed for their main proanthocyanidins and bound phenolic acids. Variations in proanthocyanidin and phenolic acid contents were studied in different barley types as well as inter-relationships between the phytochemicals and polysaccharides. The main flavanols found in the analyzed barley varieties were two dimeric as well as four trimeric forms in addition to catechin. The total amount of flavanols ranged from 325 to 527 microg/g of fresh weight of barley flour. No evident associations were found between variations in proanthocyanidin levels and different barley types. The total amount of phenolic acids ranged from 604 to 1346 microg/g of fresh weight of barley flour, with ferulic acid as the dominating acid. The amount of phenolic acids varied according to occurrence or lack of hull, with significantly higher levels in the hulled varieties.  相似文献   
106.
Negative-strand RNA viruses condense their genome into a helical nucleoprotein-RNA complex, the nucleocapsid, which is packed into virions and serves as a template for the RNA-dependent RNA polymerase complex. The crystal structure of a recombinant rabies virus nucleoprotein-RNA complex, organized in an undecameric ring, has been determined at 3.5 angstrom resolution. Polymerization of the nucleoprotein is achieved by domain exchange between protomers, with flexible hinges allowing nucleocapsid formation. The two core domains of the nucleoprotein clamp around the RNA at their interface and shield it from the environment. RNA sequestering by nucleoproteins is likely a common mechanism used by negative-strand RNA viruses to protect their genomes from the innate immune response directed against viral RNA in human host cells at certain stages of an infectious cycle.  相似文献   
107.
108.
1. The effects of light source and intensity on leg health and performance of female ROSS 308 broiler chickens were investigated in a 2 x 2 experimental design (8 groups of 275 chicks) of two light sources (Osram biolux and Osram warm-white) and two light intensities (5 and 100 clux, adjusted to fowl-perceived illuminance). 2. At 41 d of age, body weight, gait-score, footpad dermatitis and hock-burn were measured on 50 birds from each light environment. In addition, weekly feed intake and body weight were determined on a group basis and mortality was recorded continuously. 3. The light environment did not affect the severity of the gait-score or hock-burns. The risk of moderate to severe lameness and hock-burns increased with body weight. Birds weighing more than 2400 g had an increased probability of moderate footpad lesions in biolux light. 4. Weight and gait-score, as well as gait-score and hock-burn were positively correlated. Podo-dermatitis was weakly correlated with hock-burn, which contradicts earlier findings. The light environment did not affect feed intake, body weight or mortality. 5. The light sources and intensities employed in this study did not adversely affect production or leg health of broiler chickens reared semi-commercially.  相似文献   
109.
Few issues in swine production are as complex as floor space allowances. One method for pork producers to calculate floor space allowance (A) is to convert BW into a 2-dimensional concept yielding an expression of A = k * BW(0.667). Data on ADG, ADFI, and G:F were obtained from published peer-reviewed studies. Five data sets were created: A = grower-finisher pigs, fully slatted floors, and consistent group size; B = grower-finisher pigs and fully slatted floors (group size did not need to be consistent); C = grower-finisher pigs, partially slatted floors, and consistent group size; D = grower-finisher pigs, partially slatted floors (group size did not need to be consistent); and E = nursery pigs, fully slatted or woven wire floors (group size did not need to be consistent). Each data set was analyzed using a broken-line analysis and a linear regression. For the broken-line analyses, the critical k value, below which a decrease in ADG occurred, varied from 0.0317 to 0.0348. In all cases the effect of space allowance on ADG was significant (P < 0.05). Using the linear analyses based on data with k values of < 0.030, the critical k values for the 4 grower-finisher data sets did not differ from those obtained using the broken-line analysis (0.0358 vs. 0.0336, respectively; P > 0.10); however, none of the linear regressions explained a significant proportion of the variation in ADG. The slopes for the nonplateau portion of the broken-line analyses based on percent values varied among data sets. For every 0.001 decrease in k (approximately 3% of the critical k value), ADG decreased by 0.56 to 1.41%, with an average value of 0.98% for the 5%-based analyses. The use of an allometric approach to express space allowance and broken-line analysis to establish space requirements seem to be useful tools for pig production. The critical k value at which crowding becomes detrimental to the growth of the pig is similar in full- and partial-slat systems and in nursery and grower-finisher stages. The critical point for crowding determined in these analyses approximated current recommendations to ensure the welfare of pigs.  相似文献   
110.
The factors affecting the mortality of cows in Danish dairy herds were investigated by analysing data from 6839 herds. The mean risk of mortality during the first 100 days of lactation was 2.5 per cent. The risk of mortality increased with increasing herd size (odds ratio [OR] 1.05 for an increase in herd size of 50 cows), with the proportion of purchased cows (OR 1.05 for an increase in the proportion of purchased cows of 0.1), and with increases in the somatic cell count (OR 1.16 for an increase in average weighted mean somatic cell count of 100,000 cells/ml). The risk decreased with increasing average milk yield per cow (OR 0.93 for an increase in mean yield per cow-year of 1000 kg). The risk was lower in free-stall barns with deep litter (OR 0.79) than in barns with cubicles (OR 1) or tie-stalls (OR 1.04). Herds with Danish Holstein (OR 1) or Danish Jersey (OR 0.93) cows as the predominant breed had a higher risk of mortality than herds of the Danish red dairy breed (OR 0.67). The risk of mortality was lower in organic herds (OR 1) than in conventional herds (OR 1.17), and lower in herds that grazed pasture during the summer (OR 0.78).  相似文献   
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