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1.
Crias, newborn alpacas (Lama pacos), that were almost agammaglobulinemic at birth had a 70% increase in total serum proteins within 24 hours largely because of absorption of gamma globulins from colostrum. Immunoglobulin G was the isotype in highest concentration in colostrum and in serum from 24-hour-old crias. The serum IgG concentration of 10 crias increased linearly (r = 0.97) from a mean of 0.3 mg/ml (+/- 0.1 SD) for serum collected before crias suckled to a maximal mean of 30.1 mg/ml (+/- 8.1 SD) at 24 hours. The 24-hour concentration decreased by half in 10 days. Immunoglobulin M also was absorbed from colostrum and increased linearly (r = 0.99) from a mean of 0.5 mg/ml (+/- 0.1 SD) for serum collected before crias suckled to a maximal mean of 4.2 mg/ml (+/- 2.2 SD) 24 hours after birth. The 24-hour serum concentration of IgM decreased by half in 7 days. Therefore, on a weight basis, 7 times more IgG than IgM was transferred to crias; IgG accounted for greater than 85% of the passively transferred proteins in serum of 24-hour-old crias. Absorption of functional antibodies of IgG and IgM isotypes from colostrum of immunized dams by crias also was demonstrated. Immunoglobulin G and IgM antibody titers to chicken RBC increased linearly to maximal geometric mean titers of 1,139 and 843, respectively, 24 hours after birth. The 24-hour IgG and IgM antibody titers decreased by half in 6 and 3.8 days, respectively. Purified alpaca IgG had a molecular mass of 166 kilodaltons, a predominant gamma mobility, and an extinction coefficient of 14.1.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
The objective of this study is to evaluate the dilation of the ureter using endoureterotomy and an expanding-sheath double pigtail ureteral stent in the treatment of experimentally induced ureteral strictures in the porcine animal model. This is a new treatment in the ureteral strictures resolution in Veterinary Urology, although it is not a common affection, it usually appears as a consequence of ureteritis and in the iatrogenic female genital surgery. The experimental study is design in three phases: induction of experimental stricture, diagnosis and treatment of the stricture and follow-up. We have used 10 healthy Large White female pigs. The internal ureteral diameter was measured prior to laparoscopic ligature stricture induction using retrograde ureteropyelography (RUPG). Experimental stricture was diagnosed 4 weeks after intervention, using RUPG and ultrasound, and treated by endoureterotomy and subsequent placement of a double pigtail ureteral stent, which was removed 6 weeks later. The study finished 4 weeks later with measurement of ureteral diameters using RPUG and ultrasound evaluation. Except in one case, all ureters displayed permanent dilation of the strictured area for 10 weeks after treatment (6 weeks with ureteral stent and 4 more weeks without stent). Finally, this technique proved to be effective in cases of short-length and short-living ureteral strictures, and represents a viable alternative to conventional surgery in animals.  相似文献   
3.
Land-use change is forcing many animal populations to inhabit forest patches in which different processes can threaten their survival. Some threatening processes are mainly related to forest patch characteristics, but others depend principally on the landscape spatial context. Thus, the impact of both patch and landscape spatial attributes needs to be assessed to have a better understanding of the habitat spatial attributes that constraint the maintenance of populations in fragmented landscapes. Here, we evaluated the relative effect of three patch-scale (i.e., patch size, shape, and isolation) and five landscape-scale metrics (i.e., forest cover, fragmentation, edge density, mean inter-patch isolation distance, and matrix permeability) on population composition and structure of black howler monkeys (Alouatta pigra) in the Lacandona rainforest, Mexico. We measured the landscape-scale metrics at two spatial scales: within 100 and 500 ha landscapes. Our findings revealed that howler monkeys were more strongly affected by local-scale metrics. Smaller and more isolated forest patches showed a lower number of individuals but at higher densities. Population density also tended to be positively associated to matrices with higher proportion of secondary forests and arboreal crops (i.e. with greater permeability), most probably because these matrices can offer supplementary foods. The immature-to-female ratio also increased with matrix permeability, shape complexity, and edge density; habitat characteristics that can increase landscape connectivity and sources availability. The prevention of habitat loss and isolation, and the increment of matrix permeability are therefore needed for the conservation of this endangered Neotropical mammal.  相似文献   
4.
Lettuce can be associated with arbuscular mycorrhizal fungi (AMF). This symbiosis involves a molecular dialogue between fungus and plant that includes the activation of antioxidant, phenylpropanoid, or carotenoid pathways. The objective of this study was to test if the association of lettuce with AMF benefited plant growth and increased the contents of compounds potentially beneficial for human health. Results showed that AMF improved growth of lettuce, thus producing a dilution effect on the concentrations of some mineral nutrients (e.g., Ca and Mn). However, Cu, Fe, anthocyanins, carotenoids, and, to a lesser extent, phenolics appeared in higher concentrations (on a wet basis) in mycorrhizal than in nonmycorrhizal plants.  相似文献   
5.
To compare the effect of substrate-based and commercial arbuscular mycorrhizal fungi (AMF) in salt stress tolerance of Romaine lettuce a bifactorial analysis was carried out. Under non-saline conditions, only plants inoculated with formulation 1 stimulated shoot weight but not related with greater root AMF colonization. Phosphorus and potassium concentrations in leaves were improved by mycorrhizal association. Irrigation with 100 mM sodium chloride (NaCl) did not affect leaf relative water content and we observed no osmotic adjustment in leaves from non-mycorrhizal plants. However, root dry biomass and its starch content decreased, while leaf starch and root soluble sugar concentrations were enhanced. Lettuce inoculated with formulation 2 and substrate-based Glomus intraradices showed the highest root colonization percentages. Nevertheless, none of the mycorrhizal treatments induced a significant improvement on growth of lettuce subjected to salt stress. Romaine lettuce seems to be a moderately tolerant variety to salinity and therefore, the contribution of AMF was minimized.  相似文献   
6.
The aim of this paper is to analyse the sustainability of fisheries exploitation through taking into account both the multidisciplinary and intertemporal dimension of the Basque trawl fisheries. The Rapfish methodology is used for the analysis of the ecological, economic and technological sustainability of the Basque trawl fisheries between 1992 and 2003. In accordance with what has been observed in other Rapfish studies, the analysis shows that the contribution towards sustainability depends on many different attributes. Moreover, given that the results obtained are consistent with what other bioeconomic models predict, the technique is postulated as a complementary tool for defining justifiable policy recommendations and fishery management options.  相似文献   
7.
This work reports the use of laparoscopic-transducer sonography for the examination of the urinary system in a swine model. Animals underwent a two-phase study. In the first phase, the urinary system was examined using laparoscopic sonography. In the second a partial ureteral obstruction was induced, and sonographic changes were recorded and evaluated. Sonography was used to evaluate kidneys, ureters, and bladder. Anatomic structures were evaluated and the following pathological findings were identified: renal cysts, one polycystic kidney, dilation of the renal pelvis, hydronephrosis, and one perirenal pseudocyst. Where necessary, contrast digital fluoroscopy (excretory urography and retrograde ureteropyelography) was also performed. Laparoscopic sonography mainly is used for evaluation prior to laparoscopic surgery to guide decisions relating to surgery. The quality of the images obtained laparoscopically is superior to that of percutaneous or transabdominal images, because artifacts are reduced and the contact surface of the transducer is placed directly over the study area. Laparoscopic sonography proved highly effective for studying renal and ureteral disorders prior to minimally invasive surgery.  相似文献   
8.
Red wine was stored in different oak barrels or in stainless steel, and samples were taken for two years to determine 79 aroma compounds. Aging in oak affects 41 compounds. The type of wood affects 11 compounds. At least seven different processes seem to take place concurrently in aroma evolution, and five such processes, affecting 37 compounds, are linked to the oak cask. These are extraction from the wood, oxidation of wine alcohols and amino acids, microbiological formation of ethyl phenols, sorption processes, and condensation of acetaldehyde with polyphenols. The wood can release linear gamma- and delta-lactones, beta-damascenone, and ionones. Some compounds are released very fast from wood, which suggests they lie in the external part of the wood. Some extraction profiles are too complex to be explained by physical processes. Finally, the levels of 2,5-dimethyl-4-hydroxy-3(2H)-furanone and 2-ethyl-5-methyl-4-hydroxy-3(2H)-furanone increase even in the reference wine, which suggests the presence of a precursor.  相似文献   
9.
10.
Failure of passive transfer (FPT) of immunoglobulin from colostrum was demonstrated as a major determinant of mortality in newborn alpacas (Lama pacos; crias). Serum IgG concentrations of dying crias were significantly (P less than 0.0001) lower than were serum IgG concentrations of crias that lived. Of 82 crias, 10 (12%) died within 1 month of age, and 7 of these had 0 to 9 mg of IgG/ml of serum at 48 hours after birth; 5 of the 7 had evidence of infectious diseases. The serum IgG concentrations of the remaining dead crias were 12, 13, and 20 mg/ml. On the basis of serum IgG concentrations of crias that died in the first month, FPT was defined as a 48-hour serum IgG concentration less than 9 mg/ml, which was greater than 2 SD below the 48-hour mean of clinically normal crias. Using this definition, the prevalence of FPT in the 82 crias studied was 9%. Corroborative evidence of the relationship between FPT and mortality was obtained from a retrospective study of 21 dead crias. The postmortem serum IgG concentration of 5 crias that died 2 to 10 days after birth ranged from less than 1 to 3 mg/ml; all were greater than 2 SD below the mean of age matched clinically normal crias. The range of serum IgG concentration was 2.2 to 21 mg/ml in 8 crias that died 11 to 20 days after birth; serum IgG concentration in 1 cria was greater than 2 SD below the normal mean, and 6 were greater than 1 SD below the normal mean.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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