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101.
102.
A serological survey was carried out to assess the occurrence of anti-Neospora caninum antibodies in dogs from the State of Pernambuco. A total of 625 serum samples of dogs (289 from Paulista, 168 from Amaraji and 168 from Garanhuns) were tested by an immunofluorescence antibody assay for the detection of anti-N. caninum antibodies. A total of 177 (28.3%; IC 95%, 24.9-32.1) samples were positive. The seropositivity rates found in Paulista, Amaraji and Garanhuns were 26% (IC 95%, 21-31.4), 26.2% (IC 95%, 19.7-33.5) and 34.5% (IC 95%, 27.4-42.2), respectively. Of the 177 serum samples positive to anti-N. caninum antibodies, 170 were additionally tested for the presence of anti-Toxoplasma gondii antibodies and out of these 57.6% (IC 95%, 49.8-65.2) were positive. The results indicate that dogs from Amaraji, Paulista and Garanhuns are exposed to both N. caninum and T. gondii infections. The presence of dogs infected by N. caninum in Pernambuco represents a potential risk factor for the occurrence of outbreaks of abortion in cattle and small ruminants in this state. This study is the largest serological survey on the presence of anti-N. caninum antibodies in dogs carried out in Brazil and reports for the first time the exposure to N. caninum and T. gondii in dogs from Pernambuco.  相似文献   
103.
This study aimed to characterize the annual reproductive cycle of Santa Inês sheep in the Fluminense lowland region (latitude 22° 27′ 45″ south, Rio de Janeiro, Brazil) between September 2011 and August 2012. Ten ewes were maintained in a semi-intensive system under natural photoperiods with access to pasture and shelter. Blood samples were collected every 2 weeks to determine plasma progesterone concentrations. The body condition score (BCS) was determined each month. There was no seasonal variation in the plasma progesterone concentration from the months of September to January, April, and May to August. In the months of February and April, the plasma hormone levels were higher than August to November. Seventy percent (7/10) of the sheep studied had short seasonal anestrus. The periods of anestrus were concentrated between the months of September and December (spring season) in 85.7 % (6/7) of the cases evaluated. In these cases, 57.1 % (4/7) also had short periods of reproductive inactivity during other months of the year. The progesterone values obtained in the spring corroborate the higher reproductive anestrus observed in this season. Higher plasma progesterone values were found in summer and autumn with reduction in the winter to lower values in the spring. No changes in the BCS during the study period were observed. Under the studied conditions, the Santa Inês sheep showed a low degree of reproductive seasonality. However, some individual ewes had seasonal anestrus during the spring. Further studies that include management techniques are needed to improve reproductive efficiency without hormone therapy in this breed under tropical conditions.  相似文献   
104.
A 6-year-old male, Belgian shepherd dog was presented with lethargy, oliguria, hematuria, and reluctance to move. The dog developed hypertrophic osteopathy secondary to renal pelvis transitional cell carcinoma. A nephrectomy was performed and after a year, the dog was completely asymptomatic, and no evidence of metastatic disease was present.  相似文献   
105.
The effect of colored shade nets with different shade intensities and qualities of irradiation transmittance on pepper powdery mildew was tested in mini-plots and field experiments. Leaf coverage byLeveillula taurica and leaf shedding due to the disease were more severe in the shade, by up to 275% and 70%, respectively, than in the open field. Leaf coverage byL. taurica symptoms and leaf shedding from plants grown under 25% shade black nets were higher, by up to 70% and 180%, respectively, than under 40% shade nets. The color of the shade nets affected the intensity of photosynthetically active (PAR), ultra-violet (UV), blue, red and far red radiations, the UV/blue light ratio, and percent PAR and UV transmitted. The various nets suppressed the disease differently. Black, blue-silver, green and red nets were associated with lower levels of disease in the field experiments. The red net was also superior in the mini-plots. The other results from the mini-plots were not similar to those from the field, probably reflecting more intensive epidemic development in the mini-plots. No interaction between net type and cultivar was found when two cultivars were grown under the nets. Yield was higher under nets than in the open; nevertheless, the yield from plants grown under the 40% shade black net was not higher than that of the plants under the 25% black net, despite the significantly lower levels of disease at the higher shade intensity. B-quality pepper yield was significantly higher in the plots covered by 25% shade. Yield differences between the different colored nets were also not well correlated with disease levels, probably due to factors negating the direct effect of the nets on the plants and their yield. Implementation of either ‘friendly’ (Ampelomyces quisqualis AQ10/Trichoderma harzianum T39/ sulfur/ neem seed extract) or chemical (sulfur/ pyrifenox/ Polyoxin AL/ myclobutanil/ azoxystrobin) spray regimes successfully reduced disease severity under the different nets. There was no interaction between net type and spray regime. Thus, growing sweet pepper under shade nets results in increased yields and also in higher powdery mildew severity. Disease is negatively associated with the rate of shading and is variably affected by the quality of light filtered through the different colored shade nets. http://www.phytoparasitica.org posting May 8, 2007.  相似文献   
106.
1. In a study spanning two breeding seasons, we assessed the effect of different dietary energy and protein levels on body mass, body condition, and egg production of female ostriches. 2. During the first breeding season, groups were given diets with energy concentrations of 8.5, 9.5 and 10.5 MJ/kg dry mass (DM) metabolisable energy (ME) and protein concentrations of 135, 150 and 165 g/kg. In the second breeding season, groups were given diets with ME of 7.5, 8.5 and 9.5 MJ/kg and protein contents of 105, 120 and 135 g/kg. 3. Body mass of birds on diets of 7.5 and 8.5 MJ/kg ME decreased significantly in the course of the breeding season compared with birds fed on diets with higher energy contents and body measurements decreased, suggesting a loss of body condition. 4. Females fed on diets containing only 7.5 MJ/kg ME produced significantly fewer eggs at significantly longer intervals, resulting in fewer chicks hatched. 5. There was no significant difference in egg mass, initial chick mass, chick survival to one month of age and body mass of chicks at one month. 6. Dietary protein concentrations had no effect on egg production, egg mass, hatchability, initial chick mass, chick survival or chick mass at one month old. 7. The female ostriches regained their original body mass during the 4-month rest period between breeding seasons, but significant differences in some parameters during the second breeding season suggest that they may not have fully recovered their body condition. 8. A dietary energy content of 7.5 MJ/kg proved to have an adverse effect on egg production by breeding female ostriches, and it may be concluded from this study that a diet containing 8.5 MJ ME/kg DM and 105 g/kg protein should be regarded as the minimum that can be used for breeding female ostriches without compromising egg production.  相似文献   
107.
for wood manufacturers around the world, the single biggest cost factor is known to be its raw material. Maximum volume recovery of this raw material is, therefore, of key importance for the industry. The wood products industry consists of several interrelated manufacturing steps for converting trees into logs and logs into finished lumber. Each operation usually optimises its functionality in isolation from the preceding and following operations. It is a well documented fact that the optimisation of decisions through the whole chain of operations is considerably more profitable than the optimisation of individual operations. The objective of this study was to determine the optimal machine settings for two interrelated operations, namely the sawing and ripping operations which have tradition? ally been optimised individually. A model, having two decision variables, was developed which aims to satisfy market demand at a minimal cost. The first decision was how to saw the log supply into different thicknesses by choosing specific sawing patterns. The second was to decide on a rip saw's priority value settings, which determines how the products from the primary sawing operation are ripped into products of a certain thickness and width. The techniques used to determine the machine settings included static simulation with the SIMSAW software to represent the sawing operation and mixed integer programming to model the ripping operation. A metaheuristic, namely the Population Based Incremental Learning algorithm, was used to link the simulation and mixed integer models and to determine the optimal settings for the combined process. The model's objective function was to minimise the cost of production. This cost included the raw material waste cost and the over or under production cost. The over production cost included the stock keeping costs and the under production cost was estimated as the buy?in cost of under supplied products from another wood supplier. The model performed well against current decision software available, namely the Sawmill Production Planning System package, which combines simulation and mixed integer programming techniques to maximise profit. The model added further value by modelling and determining the ripping priority settings in addition to the primary sawing patterns.  相似文献   
108.
Reduction in the rotation ages of softwood saw-log plantations in South Africa is causing increased proportions of low stiffness sawn lumber at final harvest. It has been shown for some species that the microfibril angle (MFA) of the S2 layer of tracheids is strongly related to the modulus of elasticity (MOE) of wood, even more so than wood density, especially in wood formed during juvenile growth. The objectives of this study were to describe the variation in MFA in young Pinus patula trees and to determine the relationship between MFA and the dynamic MOE of sawn P. patula lumber. Thirty 16- to 20-year-old trees from six compartments from the Mpumalanga escarpment were processed into discs and lumber. The MFA, density and ring width were measured at two height levels using Silviscan 3. The average annual ring MFA varied between 7° and 29°; the pattern of variation depended mainly on height level and the ring number from the pith. The MFA in P. patula followed the same within-tree variation trends as in New Zealand-grown Pinus radiata but the average MFA was lower in absolute terms and differences between height levels were less pronounced. The MFA and density exhibited highly significant Pearson correlations of 0.73 and 0.70, respectively, with board dynamic MOE. A multiple regression model, which included MFA, density and ring width, explained 71% of the variation in the dynamic MOE of boards. A sensitivity analysis on the model showed that MFA and density had approximately similar influences on predicting the dynamic MOE of Pinus patula boards.  相似文献   
109.
110.
N-Methyl,N-phenyl-2-aminonaphthalene-6-sulfonate, a fluorescence probe, adsorbs to cycloheptaamylose with a stoichiometry of 1 : 1. The fluorescence of the complex is similar to that observed when the dye is dissolved in organic solvents. Similar fluorescence is observed with the dye in ice. The results are interpreted in terms of "solvent" relaxation during the excited state lifetime of the dye.  相似文献   
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