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21.
Tracheal collapse is a common problem that is typically observed in middle-aged and older small-breed dogs. It is a structural, obstructive airway disease with a dynamic component that can affect the intra- and extrathoracic portions of the trachea and mainstem bronchi. Many methods of treatment have been suggested, including medical management and provision of extraluminal and intraluminal support. All techniques used to treat intrathoracic and mainstem bronchial collapse have been associated with major complications or limitations. This report describes the implantation of intraluminal nitinol stents to successfully treat intrathoracic as well as extrathoracic tracheal collapse in a dog. The stents are composed of material that has characteristics similar to those of the trachea; nitinol stents may provide a method of supporting intrathoracic tracheal and mainstem bronchial collapse in dogs.  相似文献   
22.
Castanea sativa is susceptible to Phytophthora spp., a serious root pathogen causing ink disease, while C. crenata and C. mollissima show resistance to infection. Interspecific controlled crosses were established for introgression of resistance genes from the resistant species into the susceptible C. sativa, and two mapping populations were created. Phytophthora cinnamomi resistance of each progeny was evaluated by root and excised shoot inoculation tests. The number of days of survival after root inoculation was the best discriminator of resistance to P. cinnamomi while the percentage of shoots with internal lesions was the symptom most associated with survival. The lesion progression rate in the excised shoot inoculation test was strongly and negatively correlated with survival in the root inoculation test. The excised shoot inoculation test appears to be a reliable approach for screening the resistance of chestnut genotypes to P. cinnamomi. Strong genetic correlations were obtained between survival and ink disease symptoms and among symptoms, indicating that common or linked genes might influence resistance to P. cinnamomi. The most resistant genotypes selected from this study will be tested for other commercial variables, such as ease of vegetative propagation and stock–scion compatibility.  相似文献   
23.
The tomato fruit quality results of biochemical and physiological changes that occur during the ripening process. Although, the pericarp total protein profiles are less polymorphic than DNA-based markers the polymorphism in those could be directly associated with fruit quality traits. The aim of this work was to identify associations between polymorphic polypeptides from fruit pericarp at two ripening stages and fruit quality traits evaluated in two segregating populations of tomato. A cross between a normal ripening cultivar of Solanum lycopersicum (C, Caimanta) and a genotype carrying the nor (non ripening) gene (N) as well as a cross between Caimanta and a cherry type tomato of S. lycopersicum var. cerasiforme (Ce) showed genetic variance for several fruit quality traits such as fruit weight, shape, solids soluble content, acidity, color and fruit shelf life. The quantitative variations observed at phenotypic level had correspondence with the polymorphism detected in the protein profiles. Indeed, the polymophic polypeptides associated with quality fruit traits and fruit shelf life would be useful to assist tomato breeding programs as protein molecular markers.  相似文献   
24.
Toxoplasma gondii strains are genetically diverse in South America. To date, hundreds of T. gondii isolates from different animal hosts were genotyped in Brazil, most of them are different from those identified around the world. This study aimed to determine T. gondii infection rate in sheep from Brazilian slaughterhouses, as well as the genotype of these isolates. T. gondii antibodies were detected in 66/602 (10.96%) serum samples through modified agglutination test (MAT) and indirect fluorescent antibody test (IFAT). MAT-HS and IFAT-IgG presented high concordance (0.95) and strong correlation (r=0.79). T. gondii DNA was detected in tissue samples of 33% (22/66) serum positive sheep by PCR of the 529 bp repetitive element. In the bioassay in mice, T. gondii were detected in mice brain or muscle tissues in 30% (20/66) of serum positive sheep. Positive samples were typed through Restriction Fragment Length Polymorphism (RFLP-PCR) using 11 markers: SAG1, SAG2 (5'-3'SAG2 and alt.SAG2), SAG3, BTUB, GRA6, L358, c22-8, c29-6, PK1, Apico and CS3. Of 22 samples, 13 were positive and 9 genotypes were identified. Four of these 9 genotypes are unique. Nine samples had negative results in RFLP-PCR typing, which may be due to low DNA concentration. Six isolates were virulent killing mice between 12 and 25 days postinfection. Two non-virulent isolates belonged to clonal type II genotype, which were not observed in Brazil previously. These findings confirm the high diversity and high frequency of virulent genotypes among Brazilian animals. This study also proved the presence of type II T. gondii in Brazil.  相似文献   
25.
This review of the use of thermographic technique in equines introduces the principles upon which infrared radiation and thermoregulatory physiology are based and describes the instrumentation used and its practical use. The advantage of this imaging technique is that it is a noninvasive thermographic examination, both from an operational (the animal and the operator) and health (no penetrating radiation is used) standpoint. Advantages and disadvantages of this technique, equine applications, and physiological assessments are discussed.  相似文献   
26.
Summary

Alternate bearing is a serious problem in many apple varieties. In fact, each year, apple trees have to be thinned in order to ensure a correct and constant balance between the reproductive and vegetative tendencies of the plant. In organic fruit growing, there is no alternative to the expensive and time-consuming process of hand-thinning. Under these conditions, the use of natural bio-stimulants which enhance the efficiency of nutrient uptake, plant fitness to different pedoclimatic conditions, and plant tolerance to stress, offers new opportunities to reduce the negative effects of alternate bearing. The aim of this work was to evaluate the effects of Actiwave®, a metabolic enhancer derived from the alga, Ascophillum nodosum, on ‘Fuji’ apple trees affected by experimentally-imposed alternate bearing. The experiments were carried in open field conditions over four consecutive years. Although the effect of Actiwave® was erratic from year-to-year, the compound generally reduced those problems linked to alternate bearing. Actiwave® had its most significant effect on alternate bearing plants that were also affected by nutrient deprivation due to the absence of fertilisation. In these trees,Actiwave® decreased the oscillations in yield between “on” and “off” years and increased the average fruit weight on plants affected by too-high a crop load. Treated trees also showed higher leaf chlorophyll contents (increased by 12%), with a consequent increase in the rates of photosynthesis and respiration. On the other hand, under standard conditions, in well-fertilised balanced plants, Actiwave® did not have any significant effect. This evidence corroborates the hypothesis that Actiwave® may be a useful tool to reduce alternate bearing in organic and low-input farming.  相似文献   
27.
The objectives of this study were to evaluate the dry matter intake (DMI), digestibility, average daily gain (ADG), microbial efficiency, empty body weight (EBW) gain, and body composition of Nellore bulls. Additionally, Nellore bull maturity was estimated, and the prediction equation for DMI, suggested by the Brazilian nutrient requirements system (BR CORTE; Azevêdo et al. 2010), was evaluated. Thirty-three Nellore bulls, with a mean initial weight of 259?±?25 kg and age of 14?±?1 months, were used in this study. Five animals were slaughtered at the beginning of the experiment (control group), and the remaining 28 were divided into 4 groups, each slaughtered at 42-day intervals. Their diet was composed of corn silage and concentrate (55:45). The power model was used to estimate muscle tissue, bone tissue, crude protein (CP), mineral matter (MM), and water present in the empty body, while the exponential model was used to estimate adipose tissue and ether extract (EE) present in the empty body. When expressed in kilograms per day, differences were observed (P?<?0.05) only for the intake of EE and neutral detergent fiber as a function of feedlot time periods. Although there was a difference in relation to nutrient intake, it did not affect (P?>?0.05) digestibility, with the exception of EE digestibility. The equation suggested by BR CORTE correctly estimates the DMI of Nellore bulls. ADG was not affected (P?>?0.05) by time spent in the feedlot. No differences were observed (P?>?0.05) for microbial efficiency; a mean value of 142 g microbial crude protein/kg total digestible nutrients was achieved. The muscle and bone tissues, CP, MM, and water present in the empty body increased as the animal grew, although at a lower rate. The adipose tissue and EE present in the empty body increased their deposition rate when the animal reached its mature weight. Maturity is defined as when an animal reaches 22 % EE in the empty body, which corresponds to 456 kg of EBW in Nellore bulls. Therefore, this study can conclude that the feedlot time period does not affect DMI, nutrient intake, ADG, or microbial efficiency. The equation proposed by BR CORTE (Azevêdo et al. 2010) correctly estimates the DMI of Nellore bulls, which reach maturity when an EBW of 456 kg is attained.  相似文献   
28.
The variability between and within breeds with respect to nematode egg counts (EPG), packed cell volume (PCV) and hemoglobin (Hb) was studied in 36 yearling female goats of the Caninde (15), Bhuj (6) and Anglo-Nubian (15) breeds, exposed to Haemonchus contortus. Nematode-free goats were turned to a contaminated paddock in late February. From then on, fecal egg per gram counts (EPG), packed cell volume (PCV) and hemoglobin (Hb) were determined at 2-week intervals up to Week 18. The EPG, transformed as [log(EPG + 75)], varied (P < 0.01) between goats within breeds and between weeks of exposure, but not between goat breeds (P > 0.05). PCV and Hb were affected by goat breeds (P < 0.05), by goats within breeds (P < 0.01) and by weeks of exposure (P < 0.01). Anglo-Nubians had higher (P < 0.01) PCV and Hb than Caninde; Bhuj had intermediate values. There were two EPG rises; one between Weeks 6 and 10 and the other between Weeks 14 and 16. The within breed variability was marked during the EPG rise on Week 6, when individual egg counts ranged from 130 to 2500. The EPG rises coincided with drops in Hb. PCV presented a similar trend, though not as marked. Haemonchus was responsible for more than 95% of nematode eggs counted. Considering the goat as experimental unit, the correlation coefficients (r) were: -0.45, P = 0.0064, between log(EPG + 75) and PCV; and -0.53, P = 0.0009, between log(EPG + 75) and Hb. The negative correlation between egg counts and blood values suggested breed differences in PCV and Hb were related to resistance to H. contortus infection and/or to its effects.  相似文献   
29.
To investigate the impact of different dietary lipid sources on fillet composition and lipid transport, we conducted a feeding trial and evaluated the proximate composition of muscle tissue, fatty acid profiles, total cholesterol (in muscle and plasma), triglycerides, and lipoprotein concentrations in Nile tilapia, Oreochromis niloticus. Five semi‐purified diets, containing different oils (soybean – SO, corn – CO, linseed – LO, fish – FO, and olive – OO), were supplied to tilapia for 160 d. Fish fed with LO and FO diets had a lower percentage of total lipids in muscle compared with the others (P < 0.05). The highest percentage of protein was found in fish fed with FO diet (P < 0.05). The muscle fatty acid profile was influenced differently by diets (P < 0.05). The group supplemented with SO and CO had a higher concentration of 18:2n‐6, whereas the fish fed with LO diet had a higher level of 18:3n‐3 and those that received the FO diet had more 22:6n‐3 in comparison with those supplemented with vegetable oils. Plasma lipid transport was also affected by the diets: the fish fed with FO diet had higher total cholesterol and high‐density lipoprotein and lower very‐low‐density lipoprotein concentrations (P < 0.05).  相似文献   
30.
CTX‐M‐type extended‐spectrum β‐lactamase (ESBL)‐producing Enterobacteriaceae have become identified in marine ecosystem constituting a serious ecological issue. In this respect, although contamination of coastal waters and seafood, and even colonization of seabirds and fishes have been increasingly reported, molecular data are lacking to elucidate the clinical impact of ESBL producers in infected marine animals. In this study, using a genomic approach, we have analysed the genetic background of CTX‐M‐15‐producing Enterobacter hormaechei (belonging to the international human clone ST114) and Citrobacter freundii (ST265) co‐infecting a free‐living green turtle (Chelonia mydas) suffering from septic arthritis, which progressed to generalized coelomitis and death. Wide resistome of these pathogens contributed to treatment failure and death of the animal.  相似文献   
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