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51.
In Brazil, citrus black spot (CBS) caused by Guignardia citricarpa is a major disease that has different symptoms on fruit. In this study, fruit of Citrus sinensis infected by G. citricarpa and showing the symptoms false melanosis, freckle spot and hard spot were cross-sectioned and analysed anatomically and histochemically by light microscopy. Immuno-histological assays were performed. All symptoms were accompanied by a thickening of the cuticle. False melanosis lesions did not contain pycnidia and remained restricted to the epicarp or to the first layers of the mesocarp. The stomata in this type of lesion showed phenolic compounds in the guard cells and in the sub-stomatal chamber. In some samples, the guard cells and their surrounding cells lysed, and a wound meristem began to form underneath them. Freckle spot and hard spot lesions had very similar histological alterations to the epicarp and mesocarp, but in our samples only hard spot lesions contained pycnidia. Both of these symptoms were accompanied by protein inclusions. Epidermal and sub-epidermal cells located in the oil-gland region were obliterated, causing alterations in these structures. All symptoms had regions that stained strongly for lipids and phenols.  相似文献   
52.
Canine babesiosis is an infectious disease caused by either Babesia gibsoni or Babesia canis protozoans. The latter is also classified under three different phylogenetic groups, referred to as subspecies B. canis canis, B. canis vogeli and B. canis rossi. The objective of the present study was to validate and standardize a PCR assay to discriminate the organisms at the subspecies level. First, the reference sequences of the 18S rRNA, 5.8S rRNA and 28S rRNA genes, including the internal transcribed spacer 1 (ITS1) and 2 (ITS2) of the most common species and subspecies of the genus Babesia were retrieved from the GenBank database. Subspecies-specific primers (BAB3, BAB4 and BAB5) and one genus-specific primer were designed from the alignment of the sequences. The PCR assays were evaluated in three different combinations of primer pairs in order to assure complete specificity for each reaction. The results of the tests had demonstrated effectiveness of the novel primer pairs BAB1/BAB3, BAB1/BAB4 and BAB1/BAB5 for the amplification of the subspecies-specific target fragments of 746 bp (B. c. canis), 546 bp (B. c. vogeli) and 342 bp (B. c. rossi) by PCR. The original enzymatic amplification assays with novel primers reported in this paper were confirmed to be a reliable tool for the specific discrimination among B. canis subspecies by single-step PCR assays.  相似文献   
53.
Our study assessed the efficiency of a formulated new extender in maintaining viability and morphological integrity of Colossoma macropomum spermatozoa under chilling storage. Semen was diluted in the test extender and BTS? (Beltsville Thawing Solution) and exposed to a short‐term storage at 4.6 ± 0.6°C for 96 hr. Both extenders were able to maintain 17% ± 8% motile spermatozoa by the end of experiment. Sperm dilution in test extender did not affect the morphologically normal cells (61% ± 6%) up to 48 hr of chilling, being higher than in BTS? (50% ± 6%) (p < 0.05). After 96 hr, samples kept in the test extender had 50% of normal spermatozoa, whereas those kept in BTS? presented only 38% of normal cells. Chilling storage increased the incidence of cells with strongly coiled flagella in BTS?. Our study is the first to evaluate in detail the spermatozoa morphology as indicative of C. macropomum semen viability. The new extender was able to protect the spermatozoa against increase in coiled flagellum injuries.  相似文献   
54.
55.
The growth hormone receptor (GHR) is the cell surface receptor for growth hormone (GH) and is required for GH to carry out its effects on target tissues. The objectives of the present study were to estimate the allele and genotype frequencies of the GHR/Alu I gene polymorphism located in the regulatory region in beef cattle belonging to different genetic groups and to determine associations between this polymorphism and growth and carcass traits. Genotyping was performed on 384 animals, including 79 Nellore (Zebu), 30 Canchim (5/8 Charolais + 3/8 Zebu), 30 Simmental × Nellore crossbred and 245 Angus × Nellore crossbred cattle. Alleles Alu I(+), Alu I(−) and Alu I(N)null allele–were evidenced for the GHR/Alu I polymorphism and the frequency of the Alu I(N) allele was significantly higher than the frequency of the Alu I(+) and Alu I(−) alleles in all genetic groups. Genotype Alu I(N/N) of the GHR/Alu I predominated in Nellore animals, while the Alu I(N/+) and Alu I(N/−) predominated in the other genetic groups. In the association studies, traits of interest were analyzed using the General Linear Model (GLM) procedure of the SAS program and least squares means of the genotypes were compared by the Tukey test. Significant associations (P < 0.05) were observed between the Alu I(N/N) genotype of the GHR/Alu I polymorphism and lower weight gain and body weight at slaughter, although a confounding between genotypes and genetic groups may have occurred.  相似文献   
56.
A tiletamine hydrochloride-zolazepam hydrochloride combination was used successfully to immobilize 27 free-ranging maned wolves (Chrysocyon brachyurus) at a mean dose of 2.77+/-0.56 (mean+/-SD) mg/kg. The induction time ranged from 3-15 min. Animals remained immobilized for periods of 48.56 +/-12.65 min. Compulsive licking, excessive salivation, muscle twitching, muscle tremors, tachypnea, and bradycardia were observed associated with the induction of the anesthesia in 13 of 27 maned wolves. Muscle twitching, pedal withdrawal reflex, muscle tremors, and ataxia were observed during recovery in three (11%) maned wolves. There were no significant differences in heart rates (P = 0.44), respiratory rates (P = 0.82), and rectal temperatures (P = 0.54) recorded at 5, 15, and 25 min after induction at these dosages. The tiletamine hydrochloride-zolazepam hydrochloride combination was shown to be an effective and safe immobilizing agent for free-ranging maned wolves.  相似文献   
57.
OBJECTIVE: To estimate intraocular pressure (IOP) in eyes of healthy camelids, using applanation tonometry. ANIMALS: The eyes of 34 camelids (16 llamas [Lama glamal and 18 alpacas [L. pacos]) that did not have major abnormalities of the ocular surface or intraocular abnormalities. PROCEDURE: Tonometry measurements were obtained from each eye 3 times during a 24-hour period. Each measurement was the mean of several corneal applanations obtained by use of an applanation tonometer. Data were analyzed, using an ANOVA for a repeated-measures design. RESULTS: Mean (+/- SEM) IOP of llamas and alpacas was 13.10+/-0.35 and 14.85+/-0.45 mm Hg, respectively. Range of IOP was 7 to 18 mm Hg for llamas and 11 to 21 mm Hg for alpacas. Mean IOP of llamas was significantly less than the mean IOP of alpacas. Significant differences in IOP were not detected between the right and left eye of animals. Significant differences in IOP were not attributed to sex, age, or time of measurement within llamas or alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Establishing the mean and range of IOP of clinically normal llamas and alpacas provides a frame of reference that is important for use in a complete ophthalmic examination of camelids, which can assist clinicians in the diagnosis of glaucoma and uveitis. Reasons for the difference in mean IOP between llamas and alpacas are unknown. Although the difference may be unimportant clinically, this finding reiterates the fact that caution must be used when extrapolating IOP among species.  相似文献   
58.
Ninety-one Escherichia coli isolates obtained from diarrheic and normal feces of newborn piglets (0-11 days of age) from three states of Brazil were assessed for phenotypic and genotypic characteristics associated with pathogenic processes. These isolates expressed fimbriae F18ac and type 1, but not fimbriae K88, K99, 987P or F41. Genes for toxins (LT-I, STa, SLT-I, SLT-II, SLT-IIv) either individually or combined were found to be present in most of the diarrheic strains (65.7%) and in 42.8% of the non-diarrheic ones. The eaeA gene was present in 25.7% of the diarrheic isolates and in 9.5% of the non-diarrheic ones. Colicin, hemolysin and aerobactin were also found to be produced by some strains from both sources. Because of the great variety of biological characteristics associated with different illness processes, we suggest that, in Brazil, pigs may act as a reservoir for transmission of Escherichia coli strains to other animals.  相似文献   
59.
The effects of atmospheric deposition upon elementcycling and turnover in three rain forest ecosystems ofthe Serra do Mar, a mountain range along the atlanticcoast of Brazil, have been investigated as part of aninterdisciplinary German-Brazilian research project ondispersion, transformation and deposition of airpollutants in the vicinity the industrial complex ofCubatão, State of São Paulo. The projectincluded on-site measurements from 1991 to 1995, fieldexperiments and mathematical modelling with the goalof providing damage evaluation and risk assessment,and elucidating damage mechanisms with respect tosoils and vegetation. The role of the `Soil Module'sub-project reported here was to assess atmosphericdeposition and fluxes with precipitation and soilwater, and to investigate possible soil changesinduced by atmospheric deposition as well asbiological effects of pollutants via the soil path.Part I of this paper deals with concentrations ofchemicals in precipitation, soil water, surface waterand in litter. Part II will cover fluxes of chemicalsand element budgets.Three sites were chosen which differed significantlywith respect to pollution impact. Annual averages ofionic concentrations in precipitation found in openfield and below the tree canopy amounted to 5 and10 mg L-1, respectively, for sulfate-S, 0.4 and0.7 mg L-1 for nitrate, 0.65 and 1.1 mg L-1 for fluoride,1.8 and 2.6 mg L-1 for ammonium-N, 0.76 and 2.3 mg L-1for Mg, and 3.5 and 7.5 mg L-1 for Ca at the mostpolluted site. The relatively `clean' reference siteattained 1/3 to 1/9 of these averages, thus clearlyreflecting the difference in air pollution load.Chemical composition in the liquid phase is completelychanged when precipitation infiltrates the soilprofile. Nitrate concentration increases by the factor5 to 20. A clear increase is also found for sulfateand chloride. Concentration changes during ecosystempassage of seepage are interpreted in relation tochemical reactions taking place in differentcompartments. They are characterized by an almostcomplete retention of ammonium and some retention ofsulfate in the upper soil layers, and at the mostpolluted site by mobilization of Al from soil mineralsand very high leaching of nitrate as a consequence ofnitirification of organic matter.  相似文献   
60.
The intensification of dog, cat and livestock vaccination campaigns significantly reduced rabies cases in humans and domestic animals in Ceará State, Brazil. However, sylvatic animals—bats (order Chiroptera), wild canids, raccoons and non‐human primates— remain as reservoirs for the virus. Our hypothesis is that surveillance and monitoring of rabies virus in bats, especially passive surveillance, is of fundamental importance, besides the implementation of health education and strengthening of surveillance actions in humans exposed to aggressions. Thus, we assessed the occurrence of rabies virus in animals focusing on bats, before and after launching of the Sylvatic Rabies Surveillance Program in 2010. Surveillance data from the 184 municipalities of Ceará State were analysed, collected during the periods 2003–2010 (active surveillance) and 2011–2016 (passive surveillance), respectively. A total of 13,543 mammalian samples were received for rabies diagnosis from 2003 to 2016. Of these, 10,960 were from dogs or cats (80.9%), 1,180 from bats (8.7%), 806 from other sylvatic animals (foxes, marmosets, raccoons; 6.0%) and 597 from herbivores (cattle, goats, sheep, equines, pigs; 4.4%). A total of 588 (4.3%) samples were positive for rabies. About 8.4% (99/1,180) of the bat samples were infected with rabies virus, 92 (92.9%) of these were from non‐haematophagous bat species and 7 (7.1%) from haematophagous species. The number of bat samples received and infection rates increased considerably, after a shift from active surveillance (9/355 [2.5%] samples positive), to passive surveillance (90/825 [10.9%] samples positive). Surveillance of rabies virus in bats is fundamental for human and domestic animal health in Ceará State. Bats have to be considered as targets in surveillance and control programmes. Virus lineages should be characterized to increase knowledge on transmission dynamics of sylvatic rabies virus to domestic animals and the human population, and to provide additional evidence for planning and implementation of improved control measures.  相似文献   
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