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71.
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
72.
Aksoy M Kaya A Uçar M Lehimcioglu N Tekeli T 《DTW. Deutsche tier?rztliche Wochenschrift》2002,109(9):416-418
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
73.
Jos Diomedes Barbosa Carlos Magno C. de Oliveira Marcos Dutra Duarte Gabriela Riet-Correa Paulo Vargas Peixoto Carlos Hubinger Tokarnia 《Journal of Equine Veterinary Science》2006,26(9):393-398
The clinical and pathological aspects of a neurological disease observed in 16 horses in Pará, Amazonia, Brazil, are presented. The symptoms were mainly motor incoordination, paresis of the tongue, somnolence, difficulties in apprehension, chewing and swallowing of food, as well as instability and standing with abducted members. The clinical course was subacute or chronic and in most cases was not fatal. Postmortem examination performed in one already very sick, euthanized animal, did not show significant macroscopic lesions; histopathological examination revealed slight edema and degenerative alterations of a few axons, mainly in the medulla oblongata. In all pastures where horses were affected, plenty of bamboo had been eaten, probably because of scarcity of pasture. By feeding large amounts of fresh bamboo leaves of this region, in different growing stages, to three horses (horse 1, 47 g/kg/d for 30 days; horse 2, 10 g/kg/d for 60 days; horse 3, 18 g/kg on the first day, and 31 g/kg/d for 6 more days)—the animals ate the leaves unassisted—it was possible to reproduce nervous symptoms essentially identical to those observed in the natural disease 24 to 72 hours after the first feeding of the plant. In spite of continuous administration of the plant, intensity of the clinical signs did not increase. Based on field observations and comparison of the clinical and pathological pictures seen in the natural and experimental disease, the described illness can be concluded to be caused by the ingestion of large amounts of the leaves of Bambusa vulgaris f. vulgaris. 相似文献
74.
Gabriela Claudia Cangahuala-Inocente Lírio Luiz Dal Vesco Douglas Steinmacher Antonio Carlos Torres Miguel Pedro Guerra 《Scientia Horticulturae》2007
Pineapple guava (Acca sellowiana) syn. Feijoa sellowiana, a Brazilian indigenous Myrtaceae is under domestication in South Brazil. Previous works showed that this species is responsive to somatic embryogenesis and recalcitrant to conventional methods of clonal propagation. In the present work it was evaluated the role of components of culture medium in the induction and development of somatic embryos. The technology of synthetic seeds was also evaluated. Zygotic embryos were inoculated in LPm medium supplemented with 8 mM glutamic acid and 8 mM l-glutamine, 2,4-dichlophenoxiacetic acid (20 μM) and myo-inositol. For conversion of somatic embryos and synthetic seeds it was tested the effect of 6-benzylaminopurine and gibberellic acid combined or not with activated charcoal. The highest values for embryogenetic induction (100%) and number of somatic embryos/explant (113) were observed in the LPm medium supplemented with Glu (8 mM), and 2,4-D. The culture medium supplemented with BA (0.5 μM) and GA3 (1 μM) and activated charcoal (1.5 g L−1) enhanced the conversion of somatic embryos to plantlets. Pre-germinated somatic embryos encapsulated in sodium alginate with BA (0.5 μM) and GA3 (1 μM) developed radicles. The use of synthetic seed was a requisite for the survival of plantlets. 相似文献
75.
76.
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
77.
Campos FR Januário AH Rosas LV Nascimento SK Pereira PS França SC Cordeiro MS Toldo MP Albuquerque S 《Fitoterapia》2005,76(1):26-29
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
78.
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
79.
80.
Characteristics and decomposition rates of pruning residues from a shaded coffee system in Southeastern Brazil 总被引:1,自引:0,他引:1
In the Zona da Mata Mineira of Southeastern Brazil the development of sustainable land requires the integration of crops with trees. The objectives of this study then were to (i) characterize prunings from the main tree species in an agroforestry system; (ii) determine the effects of the physical and chemical characteristics of the prunings on their decomposition patterns in the laboratory; (iii) assess the effect of mixing leaves of different species on decomposition rates; and (iv) propose a decomposition index for the residues studied. The study was carried out with pruning residues from Cajanus cajan, Solanum variable, Cassia ferruginea, Piptadenia gonoacantha, Croton urucurana, and Melinis multiflora. The materials were characterized for total C, N, P, Ca, Mg and K contents; lignin, cellulose, hemicellulose and soluble polyphenols contents. The pruning residues had high polyphenols and lignin contents, high C:N and C:P ratios, and low contents of Ca, Mg, and K. The low decomposition rates of the prunings were related to the P, K, hemicellulose and polyphenol contents. The rates of N mineralization from most of the residues indicate that there is a potential to supply the needs of a crop of maize. The residues of some species, if decomposed alone, would not supply sufficient nutrients, and need to be mixed with leaves of other species.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献