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81.
The influence of five rootstocks (Evrica, Krymsk® 86, Torinel, PAC 00-08 and PADAC 01-47) on flowering, fruit set, trunk cross-sectional area, yield efficiency and fruit quality parameters of apricot cultivars (Prunus armeniaca L.) grown in a Mediterranean agro-climatic environment was evaluated. The five rootstocks were grafted with ‘E-101’ and ‘E-404’ apricot cvs., and established in an experimental orchard in the Region of Murcia (South-eastern of Spain) in 2004. Rootstock had no significant influence on the number of flowers but affected fruit set. Evrica, PAC 00-08 and PADAC 01-47, induced a higher percentage of fruit set on the apricot cultivar ‘E-101’. The greatest TCSA was exhibited with Torinel, Evrica and PADAC 01-47. The yield efficiency was significantly greater on PADAC 01-47, because of its higher yield and cumulative production compared with the other rootstocks. Thus, differences in precocity among rootstocks became evident, PADAC 01-47 being the most efficient rootstock for the first bearing years. The fruit quality traits were also significantly affected by rootstocks. In the case of ‘E-101’, the highest fruit weight was induced by Evrica, Krymsk® 86 and Torinel. In relation to fruit size, the smallest equatorial, suture and polar diameters were produced by fruit on PADAC 01-47 for both cultivars. The highest firmness was induced by PAC 00-08 for ‘E-101’, while in ‘E-404’ the highest firmness was induced by PADAC 01-47. The colour of fruit was also affected by the rootstock. The brightest coloured skin (high L* values) was found on Evrica, PADAC 01-47, Torinel and Krymsk® 86. The fruit weight was positively correlated with pulp yield and negatively correlated with TCSA. According to these results, higher fruit quality was found on PADAC 01-47 and Evrica.  相似文献   
82.
A field study was conducted in Brazil to evaluate the efficacy of single vaccination of pigs with two bacterins to prevent Mycoplasma hyopneumoniae lung lesions. The first (T1) treatment group (174 pigs) was injected with 2 mL of saline solution; group T2 (177 pigs) with 2 mL of bacterin A, and group T3 (174 pigs) with 2 mL of bacterin B. On days-on-test (DOT) 0, 35, 66, 97 and 125, blood samples and tonsil swabs were collected from selected pigs for antibody determination (indirect ELISA) and PCR assay for the presence of M. hyopneumoniae. Pigs were slaughtered on DOT 126-129 and lung lesions were scored blindly. Bacterin A vaccinated pigs had significantly (P < or = 0.05) lower lung lesion scores (0.2%) than bacterin B (0.4%) or saline-treated pigs (1.2%); there was also a significantly lower (P < or = 0.05) number of pigs with lung lesions (27.1%), than bacterin B (38.2%) or saline-treated (55.4%) pigs. The two vaccines had similar (P>0.05) results in terms of mean weight gain, average daily weight gain, feed efficiency, frequency of PCR positives, and there was similar antibody conversion (ELISA). It was concluded that although the productivity parameters and antibody conversions were similar, bacterin A was more effective in preventing and reducing the severity of lung lesions than bacterin B.  相似文献   
83.
Maedi-Visna (MV) and ovine pulmonary adenocarcinoma (OPA) are two retroviral diseases occurring worldwide that affect adult sheep. Differences in incidence, which may be related to sheep-rearing and housing choices, as well as to genetics, and disease progression have been reported for both diseases. In this work four microsatellites located in immune-relevant regions, the major histocompatibility complex (MHC) region, interferon-γ and interleukin-12p35, were genotyped to determine their association with disease progression. The analysed sample included Latxa sheep with and without OPA and MV-characteristic lesions in their lungs. The microsatellites in the MHC were the most diverse, while the ones located in the cytokines were the less polymorphic. In the case of IFN-γ the results suggested the presence of null alleles. Significant results were detected for several microsatellite alleles in the association analysis carried out by logistic regression. All statistical analyses included a flock effect adjustment to avoid false positives due to genetic structuration. MHC Class I microsatellite alleles OMHC1*205 and OMHC1*193 were associated with disease progression for Maedi and OPA, respectively. Moreover, MHC Class II microsatellite allele DRB2*275 was associated with presence of lesions in Maedi. Furthermore, the MHC microsatellites were combined for a bioinformatic haplotype inference with the PHASE software. In total, 73 haplotypes were detected, 18 of them in more than 6 animals. After standard and weighted logistic regression analysis, two of them were significantly associated with susceptibility: OMHC1*205-DRB2*271 for Maedi and OMHC1*193-DRB2*271 for OPA, both with the Class I microsatellite alleles associated in the marker by marker study. Although more extensive analyses are needed to disentangle the relationship between host genetics and disease, as far as we know this is the first study demonstrating a significant association between sheep MHC Class I microsatellite alleles and susceptibility to Maedi-Visna and OPA viral diseases.  相似文献   
84.
The relationship between the immune response and the pathogenesis of the disease was studied in different primary and secondary experimental Fasciola hepatica infections of goats. The establishment of the infection, measured as percentage of recovered flukes at the necropsy, was similar in primarily and secondarily infected animals (between 19.7% and 24.3%), but the hepatic damage was much more severe in secondarily infected goats, as revealed by the levels of serum hepatic enzymes GGT and LDH. Primary infection evolves to chronic fasciolosis that did not induce the development of resistance, since goats were highly susceptible to secondary infection, showing severe acute and chronic hepatic lesions that led to the death of some animals in each group. The immune response to the infection was proved by the production of specific IgG antibodies to ESP of F. hepatica and the involvement of CD3+ T lymphocytes and lambda IgG+ plasma cells in the hepatic infiltrate. Secondary infection did not induce any difference in either IgG response or in the cellular composition of the infiltrate of hepatic lesions, although this was much more extended. However, neither antibodies nor cell-mediated response were protective: there was no correlation between IgG levels and fluke burden and there was no evidence of cell-mediated killing of the parasite. This suggests the existence of some immune evasion mechanisms in goat infection with F. hepatica. The parasite may depress the local inflammatory and immune response, as suggested by the scarcity of CD3+ T cells in the infiltrate surrounding acute migratory tunnels. Moreover, in secondary infected goats can be suspected an immunological damage of the liver, since a very severe infiltrate of immune cells replaced wide areas of hepatic parenchyma and an immune-mediated damage of hepatocytes could occur.  相似文献   
85.
Brucellosis control and eradication requires serological tests and vaccines. Effective classical vaccines (S19 in cattle and Rev 1 in small ruminants), however, induce antibodies to the O-polysaccharide of the lipopolysaccharide which may be difficult to distinguish from those resulting from infection and may thus complicate diagnosis. Rough attenuated mutants lack the O-polysaccharide and would solve this problem if eliciting protective immunity; the empirically obtained rough mutants 45/20 and RB51 have been used as vaccines. Strain 45/20 is reportedly unstable and it is not presently used. RB51 is increasingly used instead of S19 in some countries but it is rifampicin resistant and its effectiveness is controversial. Some controlled experiments have found good or absolute protection in adult cattle vaccinated orally (full dose) or subcutaneously (reduced dose) and in one field experiment, RB51 was reported to afford absolute protection to calves and to perform better than S19. Controlled experiments in calves, however, have shown reduced doses of RB51 to be ineffective, full doses only partially effective, and RB51 less effective than S19 against severe challenges. Moreover, other observations suggest that RB51 is ineffective when prevalence is high. RB51 is not useful in sheep and evidence in goats is preliminary and contradictory. Rough mutants obtained by molecular biology methods on the knowledge of the genetics and structure of Brucella lipopolysaccharide may offer alternatives. The B. abortus manBcore (rfbK) mutant seems promising in cattle, and analyses in mice suggest that mutations affecting only the O-polysaccharide result in better vaccines than those affecting both core and O-polysaccharide. Possible uses of rough vaccines also include boosting immunity by revaccination but solid evidence on its effectiveness, safety and practicality is not available.  相似文献   
86.
Ocular ultrasonography in horses represents a valuable imaging diagnostic tool for the diagnosis of intraocular and periocular diseases, particularly when cornea or lens opacities preclude ophthalmoscopy of deeper structures. The authors studied normal and pathological aspects of the eye. Nineteen horses with opacities of the dioptric structures underwent an ultrasound examination. This technique allowed the diagnosis of a posterior synechia (1), cataracts (8), vitreous opacities (6), retinal detachment (3), and a foreign body (1). Ultrasonography provided helpful information about the structure and vascular pattern when the conventional ophthalmic evaluation was unable to achieve a correct diagnosis.  相似文献   
87.
Short- and long-term field experiments are necessary to provide important information about how soil carbon sequestration is affected by soil tillage system; such systems can also be useful for developing sustainable crop production systems. In this study, we evaluated the short- and long-term effects of conservation tillage (CT) on soil organic carbon fractions and biological properties in a sandy clay loam soil. Both trials consisted of rainfed crop rotation systems (cereal–sunflower–legumes) located in semi-arid SW Spain. In both trials, results were compared to those obtained using traditional tillage (TT). Soil samples were taken in flowering and after harvesting of a pea crop and collected at three depths (0–5, 5–10 and 10–20 cm). The soil organic carbon fractions were measured by the determination of total organic carbon (TOC), active carbon (AC) and water soluble carbon (WSC). Biological status was evaluated by the measurement of soil microbial biomass carbon (MBC) and enzymatic activities [dehydrogenase activity (DHA), o-diphenol oxidase activity (DphOx), and β-glucosidase activity (β-glu)].The contents of AC and MBC in the long-term trial and contents of AC in the short-term trial were higher for CT than TT at 0–5 cm depth for both sampling periods. Furthermore, DHA and β-glucosidase values in the July sampling were higher in the topsoil under conservation management in both trials (short- and long-term). The parameters studied tended to decrease as depth increased for both tillage system (TT and CT) and in both trials with the exception of the DphOx values, which tended to be higher at deeper layers.Values of DHA and β-glu presented high correlation coefficients (r from 0.338 to 0.751, p ≤ 0.01) with AC, WSC and TOC values in the long-term trial. However, there was no correlation between either TOC or MBC and the other parameters in the short-term trial. In general, only stratification ratios of AC were higher in CT than in TT in both trials. The results of this study showed that AC content was the most sensitive and reliable indicator for assessing the impact of different soil management on soil quality in the two experiments (short- and long-term).Conservation management in dryland farming systems improved the quality of soil under our conditions, especially at the surface layers, by enhancing its storage of organic matter and its biological properties, mainly to long-term.  相似文献   
88.
An experiment was performed to evaluate the performance of Patagonian pejerrey during net cage rearing in the oligomesotrophic reservoir Exequiel Ramos Mexía. Survival, growth, nutrition and reproduction were evaluated for two lots of pejerrey, initial weights 4.0 and 2.5 g, reared in net cages for 22 and 14 months respectively. Fish were stocked at 29 and 48 individuals m?3 densities and fed with an experimental pejerrey feed. During the experiment, temperature fluctuated between 6.6 and 19.6 °C. The two lots did not show substantial differences in survival (pooled survival at the end of the experiment >80%) and the thermal‐unit growth coefficient (TGC), daily feed intake and feeding efficiency were 0.43±0.19, 1.70±0.80 and 53.6±9.9 respectively. Digestive tract analysis showed that caged pejerrey can consume substantial quantities of natural food, taking advantage of its planktivorous condition. Pejerrey showed high percentage survival, slow growth and early sexual maturation in captivity. The use of the TGC is proposed as a model for describing the growth pattern of this species and other pejerrey under culture conditions.  相似文献   
89.
One alternative to contribute to the reduction of the pressure on coral reef ecosystems brought about by an increasing demand for marine aquarium ornamentals is to improve and further develop the culture of desirable species for trade. Peppermint shrimp from the genus Lysmata are among the most intensively traded decapod in the trade and while several studies have been conducted to improve its culture, individuals obtained from culture facilities are generally paler than those collected from the wild. Because color is a fundamental component of the price tag on most marine ornamental live species, poorly colored animals command a lower price, reducing competitiveness. In this study, we evaluate the influence of tank background color (reflected light) on the morphological coloration change of Lysmata boggessi. In a 15‐d experiment, 30 individuals were exposed either to reflected‐red or white light and the relative change of coloration between initial and final moments was quantified with photography (RGB color model). At the end of the experimental period, shrimp exposed to red‐reflected light presented a more intense red coloration than those exposed to white‐reflected light. These results demonstrate that a simple change in background tank color can enhance shrimp external coloration. Such a cheap‐to‐implement procedure can support the culture of more colorful, hence more valuable ornamental shrimp that can compete with those captured from the wild.  相似文献   
90.
This is the first morpho-histological comparison of guanaco ovaries between reproductive (long-days) and non-reproductive (short-days) seasons, and oestrogen receptor-alpha (ERα) and beta (ERβ) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long-day ovaries than short-days, consistent with ovarian activity in this season. Differential expression of ERα and ERβ was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non-reproductive seasons of guanaco ovaries.  相似文献   
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