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Clinical, parasitological and biochemical parameters were evaluated in Corriedale and Crioula Lanada sheep after a single experimental infection with Haemonchus contortus. Ten 4-month-old worm-free lambs, of each breed, were infected with 200 L3 H. contortus per kg live weight and four uninfected animals of each breed were used as controls. Every week, the animals were weighed and blood and faecal samples were collected for measurement of packed cell volume (PCV), total serum protein (TSP) and albumin (ALB), and the number of eggs per gram of faeces (EPG), respectively. Twelve weeks after infection, the animals were slaughtered. The worm burden was determined and samples of the abomasal mucosa were processed for determination of the number of eosinophils, mast cells and globule leukocytes. No significant differences in PCV, TSP, ALB, parasite burden or the cell populations of the abomasal mucosa were observed between breeds, but Crioula lambs had a lower EPG count. The comparison of the infected groups with their respective controls revealed significant alterations in PCV, TSP and ALB in the Corriedale lambs and in PCV, TSP, ALB and the density of eosinophils and mast cells in the Crioula lambs.  相似文献   
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This paper reviews the epidemiology of bovine, swine, ovine, caprine, and canine brucellosis in Brazil. The zoonotic aspects of Brucella infection in Brazil is also discussed. Emphasis is given to the new program for the control of brucellosis in cattle and buffaloes that is likely to provide important insights into the prospects and strategies for controlling brucellosis in developing countries.  相似文献   
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Oestrus and calving records of Anatolian buffaloes were analyzed to investigate influence of climatic conditions on oestrus occurrence and postpartum period. Oestrus records showed a seasonal pattern concentrated between July and September which is the warmest period of the year. Likewise, more than half (52.7%) of the total calvings occurred between May and August. Month of calving significantly influenced the length of calving to first oestrus interval and open period (P < 0.01). The average length of open period was significantly shorter in autumn and summer calvers compared to those calved in spring and winter (P < 0.05) during long days. The humidity rate was negatively correlated with both calving to first oestrus interval and open period (P < 0.05). In conclusion, exposure to high environmental temperatures around 20 degrees C exerted no suppressive influence on ovarian activity in Anatolian buffaloes. Although humidity rate (P < 0.05) and ambient temperature (P < 0.01) was found to be correlated with the duration of postpartum period, day length might be the main factor regulating reproductive biorhythm and postpartum events in Anatolian buffalo cows.  相似文献   
55.
In this study, the genetic relatedness of 22 low chill requiring walnut genotypes adapted to the south east Mediterranean region of Turkey was analysed by amplified fragment length polymorphism (AFLP) markers. Relatively low level of genetic variation was detected among the genotypes examined by five AFLP primer combinations, suggesting that these walnut genotypes selected predominantly for their low chill requirement have relatively narrow genetic base. In addition, the geographical proximity of the genotypes analysed was not correlated with their level of genetic relatedness. These results have implications for walnut breeding and conservation.  相似文献   
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Veterinary Research Communications - The current study aimed at estimating the direct (condemned offal) and indirect (meat, milk, and fecundity losses) production losses due to cystic...  相似文献   
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Crude extracts and fractions of Bertholletia excelsa stem barks were tested for trypanocidal activity. Acetone and methanol extracts showed significant in vitro trypanocidal activity against trypomastigote form of Trypanosoma cruzi since in the concentration of 500 microg/ml, the parasites were reduced in 100% and 90.3% respectively, whereas the triterpene betulinic acid pure isolated from hexane extract presented 75.4%.  相似文献   
59.
Antibacterial activity of seed proteins of Robinia pseudoacacia   总被引:1,自引:0,他引:1  
A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 microg ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed.  相似文献   
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