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581.
582.
Agroforestry is a promising method for enhancing land-use sustainability in the Bolivian Andes. However, its benefits in terms of rural development are under-recognized due to gaps in understanding users?? perceptions while taking into consideration both local and global environmental goals. Our study aimed to narrow these gaps by developing an analytical framework for analyzing the site-specific socio-ecological factors and interactions related to local woody species and assessing their ecological, economic, and socio-cultural plant values in order to identify the most promising agroforestry species. The framework was then tested in an indigenous community at 2,760?C3,830?m?a.s.l., incorporating vegetation surveys, environmental studies, and interviews on plant functions. Ecological, economic, and socio-cultural values and the ecological apparency of plants were calculated, and detrended correspondence and principal component analyses helped to reveal the socio-ecological context of significant factors for plant distribution and uses. Results showed dominating seral woody species along an altitudinal gradient. Although shrubs were more ecologically apparent than trees, trees were perceived to be more valuable as the usefulness and cultural importance of species increased with plant height and timber availability. Phytosociological factors played a minor but still significant role in perceived usefulness. Schinus molle and Prosopis laevigata (<3,200?m a.s.l.), Polylepis subtusalbida (>3,200?m a.s.l.), and Baccharis dracunculifolia (both zones) were evaluated as most promising for agroforestry use. In conclusion, our analytical framework proved to be a valuable tool for context-specific agroforestry plant selection. Nonetheless, economic, technical, and socio-cultural limitations of cultivating native agroforestry species were revealed as well. Agroforestry science and practice should, therefore, focus on enhancing reproductive potentials of existing woody vegetation, as well as problem-oriented horizontal dialogues between indigenous, expert, and scientific actors.  相似文献   
583.
The effects on blood serum and colostrum immunoglobulin G (IgG) levels from including conjugated linoleic acid (CLA) in the diet were evaluated in goats. In experiment 1, 20 goats were allotted into two groups; the CLA group received 20 g/kg of dry matter of CLA 60 and the control group received 0 g/kg of CLA 60, from the third month of gestation until partum. Blood samples were taken every 2 weeks from 1 day before CLA inclusion to partum. From partum until 96 hours, blood and colostrum samples were taken every 24 h. Before partum, IgG serum blood levels were 15.6 and 9.4 mg/ml (CLA and control, respectively); the time effect was statistically significant. After partum (96 h), the effect of CLA dietary inclusion was statistically significant.  相似文献   
584.
The purpose of this study was to assess the effects of two currently available commercial European-type modified-live virus (MLV) vaccines against porcine reproductive and respiratory syndrome in a reproductive pig model. Sixteen 90-day pregnant gilts were divided into four groups and allocated to one of the following intranasal treatments: group A gilts served as negative controls; group B gilts were exposed to a virulent European field strain; group C gilts were exposed to vaccine strain VP046 Bis and group D gilts to vaccine strain All-183. The results indicated that MLV strains can replicate in breeding animals and have the ability to cross the placenta. In particular, viraemia was detected in all gilts in group C and 2/4 gilts in group D, at least at one time point. In addition, transplacental infection was demonstrated in 3/4 gilts in group C and 2/4 gilts in group D. However, congenital and early postnatal infection did not have a marked detrimental effect on piglet performance when compared to negative controls, and no statistically significant differences were observed in most cases. Conversely, the reproductive performance of gilts in group B was significantly worse than that of the other groups. Specifically, the number of born-alive piglets, the survival rate of piglets during lactation and the mean weight of weaned pigs were significantly lower. It was concluded that the two commercial European-type MLV vaccines tested had no marked detrimental effects in pregnant gilts, although the MLV strains can cross the placenta leading to the birth of congenitally infected piglets.  相似文献   
585.
The effect of partially replacing fishmeal (FM) by black soldier fly larvae meal (Hermetia meal—HM) in meagre (Argyrosomus regius) diet was evaluated for nutrient digestibility and digestive enzyme activity. For that purpose, triplicate groups of fish (18.0 ± 0.02 g) were fed during 48 days either a control diet (CTR), without HM, or one of three diets including 100, 200 and 300 g/kg of HM, replacing 17, 35 and 52% of FM, respectively. Apparent digestibility coefficients (ADCs) of dry matter, energy, protein, lysine, isoleucine, leucine, phenylalanine, alanine, glutamate, glycine and serine presented a decreasing response with increased HM inclusion. Chitin ADC was null, independent of dietary HM inclusion. Total alkaline protease activity increased while trypsin activity decreased with dietary HM inclusion. No intestinal chitinolytic activity was detected. Intestinal alkaline protease zymogram revealed nine bands with proteolytic activity against casein, with molecular weights ranging between 15 and 75 kDa. Anti‐protease activity in the intestine was not affected by dietary inclusion of HM compared to the CTR diet. Overall, it is concluded that replacement of up to 17% FM with HM (100 g/kg HM inclusion level) in meagre diets has no major adverse effects in diet digestibility and digestive enzyme activity.  相似文献   
586.
A parvovirus was isolated from the feces of an 8- and 9-month-old steer that died acutely with hemorrhagic diarrhea and microscopic evidence of a coccidial infection. The concurrent intestinal parasitism in this steer appeared to play a role in the development of clinical disease. The viral isolate was identified as a bovine parvovirus (BPV) on the basis of its size (22 nm) and icosahedral morphology, the neutralization of viral cytopathology by antiserum to BPV, a strong immunofluorescent reaction with fluorescein-labeled antiserum to BPV, and the inhibition of viral hemagglutination of guinea-pig erythrocytes by antiserum to BPV. Cell cultures infected with this isolate showed a slight nuclear fluorescent reaction with fluorescein-labeled antiserum to canine parvovirus, suggesting an antigenic relationship to canine parvovirus. Patterns of hemagglutination for this isolate with human erythrocytes from 20 donors of various blood types differed from those obtained with the reference Abinanti strain of BPV. These results indicate that blood from multiple donors of a species may be necessary to confirm the presence or absence of viral hemagglutinating activity with clinical isolates of BPV.  相似文献   
587.
Five experiments were carried out to determine the efficacy of immunization against theileriosis in an endemic area of Kenya using artificial infection with a mixture of stabilates of Theileria parva stock or natural infection and treatment with parvaquone or several formulations of oxytetracyclines. For the first four experiments, introduced, susceptible Sahiwal/Friesian crosses were used and in the fifth, calves of Boran/Maasai zebu crosses born on the site. Cattle were infected either artificially with sporozoite stabilates of local isolates of T. parva parva derived from cattle and T. parva lawrencei derived from African buffalo or exposed to natural tick challenge on the ranch mostly derived from buffalo. The cattle were then given various treatment regimens using either parvaquone or long- and short-acting formulations of oxytetracycline. Treatment of natural infections, although it can be effective, was not considered a practical method on a large scale because of the need for intensive monitoring in the case of parvaquone treatment and the possibility of cattle not becoming infected in the case of prolonged application of long-acting formulations of oxytetracycline. Both methods were relatively expensive. Artificial infection treatment proved more practical and methods were developed where the monitoring of cattle was not required during the immunization procedure. Out of a total of 16 drug regimens investigated, one (consisting of two treatments of a short-acting formulation of oxytetracycline at 10 mg kg-1 body weight on Days 0 and 3 or 4 after infection) was found to be the most efficacious and the cheapest, and has now been used on a routine basis. This method can be used successfully on calves greater than 1 month of age.  相似文献   
588.
Summary European cattle breeds are being introduced into Ethiopia in an effort to improve the productivity of indigenous breeds. The Ethiopian cattle breeds Horro and Boran were compared for tick burdens with their crosses with Friesian, Jersey and Simmental. Horro animals had the lowest tick burdens and the Horro × Friesian the highest. Adaptation to their environment and long-term natural selection for tick resistance in Horro cattle is the most likely explanation.Repeatability of tick burdens in all animals considered as one herd were only statistically significant forBoophilus decoloratus, the most abundant tick species. Statistically significant correlations between burdens of femaleB. decoloratus, Amblyomma cohaerens andRhipicephalus praetextatus were observed and the addition of the males resulted in all inter-species correlations becoming significant.Care should be taken when crossing Ethiopian with more productive European cattle breeds in order not to lower their tick and disease resistance.
Resistencia En Diferentes Razas De Ganado Vacuno A Garrapatas (ACARI: Ixodidae) En Bako Ethiopia
Resumen Ganado de raza europea estan siendo introducidos en Etiopia en un esfuerzo de mejorar la produccion de las razas indigenas. Las razas etiopes Horro y Boran fueron comparadas por sus cargas de garrapatas con sus cruzas con Friesian, Jersey y Simmental. El ganado Horro mostró las cargas mas bajas y las cruzas con Friesian las mas altas. La adaptacion al medio ambiente y la seleccion a largo plazo de este tipo de ganado es la explicacion mas probable de los resultados.La repitabilidad de las cargas de garrapatas en todos los animales agrupados en un rebaño fueron estadistícamente significativas paraB. decoloratus, la garrapata mas abundante. Correlaciones estadísticamente significativas entre las cargas de hembras deBoophilus decoloratus, Amblyomma cohaerens y Rhipicephalus praetextatus fueron observadas y la adicion de los machos resulto en que todas las correlaciones entre especies se volvieron significativas.Se debe tener cuidado cuando las razas de ganado etiopes se cruzan con las mas productivas razas europeas para no reducir su resistencia a las garrapatas y enfermedades.

Resistance De L'hote Aux Tiques (ACARI: Ixodidae) Chez Differentes Races De Betail A Bako, Ethiopie
Résumé Des races bovines européennes sont actuellement introduites en Éthiopie dans le but d'accroître la productivité des races indigènes. Ainsi, les races Horro et Boran ont été comparées du point de vue du taux d'infestation par les tiques avec les produits de levi croisement avec les races Frisonne, Jersiaise et Simmenthal. Les animaux de race Horro avaient le taux d'infestation le plus bas et le croisement Horro × Frisonne le taux le plus elevé. L'explication la plus vraisemblable de ces résultats est l'adaptation du bétail Horro à son environnement en meme temps qu'une sélection naturelle de longue date à la résistance aux tiques. La répétabilité de la pression ixodienne chez tous les animaux considérés comme formant un troupeau unique, n'a été statistiquement significative que pourBoophilus decoloratus, espèce la plus abondante. Les auteurs ont observé des corrélations statistiquement significatives entre les taux de charge relatifs aux femelles deBoophilus decoloratus, Amblyomma cohaerens etRhipicephalus praetextatus. La prise en compte des mâles a eu pour effet de rendre significative toutes les corrélations inter-espèces. Il faut donc prendre des précautions lors de croisement du bétail éthiopien avec des races européennes plus productives afin de ne pas diminuer leur résistance aux tiques et aux maladies.
  相似文献   
589.
A new disease of the fruit tree Jocote de Corona (Spondias purpurea L.) was observed in El Salvador, Central America. The symptoms included small chlorotic leaves, highly proliferating shoots, and shortened internodes. Absence of sweet pulp in fruits made them inedible, causing considerable yield losses for farmers. The disease etiology was investigated using polymerase chain reaction with phytoplasma-specific primers, sequencing, and phylogenetic analysis. We obtained no amplification products from symptomless plants, whereas all tests were positive from plants with symptoms. Phylogenetic analysis indicated that this phytoplasma clustered in the 16S rIII group, the type member of which is X-disease phytoplasma. This is the first report of a phytoplasma associated with Jocote de Corona disease in El Salvador and Central America. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession number AJ888471  相似文献   
590.
The aim of this study was to determine the in vitro antifungal activity of several antifungal drugs (posaconazole, nystatin, miconazole and clotrimazole) against Malassezia pachydermatis with microdilution and agar dilution techniques. Malassezia pachydermatis isolates were obtained from the skin and ears of dogs. Tests on solid media were performed using 25-well Petri dishes (2 mL/well containing Sabouraud's dextrose agar and diluted antifungal drug) inoculated with 5 μL suspensions of M. pachydermatis . Microtitre broth dilution used 96-well microtitre plates containing Sabourauds dextrose broth and appropriate dilutions of antifungal drugs, inoculated with 10 μL standard suspensions of M. pachydermatis . Plates were inoculated in duplicate and incubated at 30°C for 5 days and growth assessed. The four antifungal drugs were tested in 10 dilutions (4.0-0.007 μg/mL for posaconazole, and 32--0.06 μg/mL for clotrimazole, miconazole and nystatin). Results obtained for 83 strains of M. pachydermatis and a control reference strain (CBS 1879) exhibited the same pattern. Results of the MIC between microtitre and agar methodologies showed no significant differences (≤ 2-fold) across all drugs. For both solid and liquid methods, posaconazole was the most effective antifungal drug of the four tested with MIC90 of 1–2 μg/mL for posaconazole, 16–32 μg/mL for clotrimazole, and ≥ 32 μg/mL for miconazole and nystatin.
Funding: Schering-Plough.  相似文献   
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