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91.
The objective of the research was to evaluate the efficiency of the spermatogenesis through the morphology of the testicular parenchyma in bulls of different zebu breeds. We used testicular fragments from bull of the breeds Nelore (n = 10), Polled Nelore (n = 6), Gyr (n = 5), Guzerat (n = 5) and Tabapuã (n = 5). The tissue was perfused with Karnovsky solution, included in glycol methacrylate and stained with toluidine blue–sodium borate 1%. Animals of the Nelore breed presented higher population of primary spermatocyte in pre‐leptotene/leptotene (38.30) and in pachytene (38.14) and round spermatids (113.30), higher yield of spermatogonia mitosis (21.2) and higher daily spermatic production per gram of testicular parenchyma (32.8 × 106) than those from breeds Gyr, Guzerat and Tabapuã and higher general yield of spermatogenesis (62.4) than breeds Gyr and Tabapuã. There was no significant difference in any of the evaluated parameters between breeds Nelore and Polled Nelore. The rate of Sertoli cells did not vary between the studied breeds. Apparently, the genetic selection applied to the breeds has been improving the yield in the spermatogenic process by decreasing cellular loss, although it did not increase the support capacity of the Sertoli cells.  相似文献   
92.
  1. The Balbina hydropower dam in the Central Amazon basin, established in the Uatumã River in the 1980s, is emblematic for its socio-environmental disaster. Its environmental impacts go far beyond the reservoir and dam, however, affecting the floodplain forests (igapó) in the downstream area (dam shadow), which have been assessed using a transdisciplinary research approach, synthesized in this review.
  2. Floodplain tree species are adapted to a regular and predictable flood pulse, with high- and low-water periods occurring during the year. This was severely affected by the operation of the Balbina dam, which caused the suppression of both the aquatic phase at higher floodplain elevations and the terrestrial phase at lower floodplain elevations (termed the ‘sandwich effect’).
  3. During the period of construction and reservoir fill, large-scale mortality already occurred in the floodplains of the dam shadow as a result of reduced stream flow, in synergy with severe drought conditions induced by El Niño events, causing hydraulic failure and making floodplains vulnerable to wildfires.
  4. During the operational period of the dam, permanent flooding conditions at low topographical elevations resulted in massive tree mortality. So far, 12% of the igapó forests have died along a downstream river stretch of more than 125 km. As a result of flood suppression at the highest elevations, an encroachment of secondary tree species from upland (terra firme) forests occurred.
  5. More than 35 years after the implementation of the Balbina dam, the downstream impacts caused massive losses of macrohabitats, ecosystem services, and diversity of flood-adapted tree species, probably cascading down to the entire food web, which must be considered in conservation management.
  6. These findings are discussed critically, emphasizing the urgent need for the Brazilian environmental regulatory agencies to incorporate downstream impacts in the environmental assessments of several dam projects planned for the Amazon region.
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93.
94.
N-butyl-cyanoacrylate tissue adhesive was evaluated as a skin closure material in a population control programme. Fifty-two female cats underwent ovariohysterectomy: skin closure of 25 of those cats was undertaken with nylon (3-0) and in 27 with the adhesive. Twenty-three cats spent the postoperative period confined in cages and 29 were free within a 50-square-metre fenced area. The parameters used for evaluation were: dehiscence or secretion and presence and extension of erythema at the surgical site. It was observed that the time required for closure of the surgical site with the adhesive was shorter than with nylon, saving approximately 1 min per animal. The adhesive or conventional suture allowed similar healing, and independent of material used for skin closure or the postoperative exercise, there was no statistical difference in wound cicatrization. As the adhesive eliminates the need for suture removal and decreases surgery time, without additional risk to the cat, it may be indicated for surgical population control programmes.  相似文献   
95.
ABSTRACT Bean golden mosaic geminivirus (BGMV) is the single most devastating virus of common beans in the tropical and subtropical Americas and the Caribbean Basin. The BGMV from Brazil, named BGMV-BZ, is considered distinct from BGMV-PR isolates from Puerto Rico, Guatemala, and the Dominican Republic because of DNA sequence data, the ability to form pseudorecombinants, and mechanical transmissibility properties. In bean-growing areas of Brazil, samples were collected from beans, lima beans, and the weed Leonurus sibiricus displaying typical symptoms of infection by geminiviruses. Viral DNA fragments comprising part of the rep gene, the common region, and part of the cp gene were amplified by polymerase chain reaction, cloned, and sequenced. The bean samples had geminivirus with sequences nearly identical to that of BGMV-BZ collected in Goiania, state of Goiás, in 1986. The sample from lima bean contained a new species of geminivirus that induces symptoms similar to those induced by BGMV-BZ and was named lima bean golden mosaic virus (LBGMV-BR). While all sequences from bean samples clustered with BGMV-BZ, the sequence from the lima bean isolate stood alone. A mixed infection with abutilon mosaic geminivirus was also found in a single sample from the state of S?o Paulo. DNA sequence comparisons indicate that the virus isolate from L. sibiricus represents a new geminivirus species, designated here as leonurus mosaic virus.  相似文献   
96.
OBJECTIVE: To compare the efficacy of 2 doses of recombinant human bone morphogenetic protein-2 (rhBMP-2) on tibial osteotomy healing in dogs. STUDY DESIGN: Experimental, randomized complete block (n=7). ANIMALS: Adult female dogs (n=21). METHODS: Right midshaft tibial osteotomies were created and stabilized with a 1-mm gap using type I external fixators. Seven dogs were untreated controls and 14 with osteotomies were treated with either 0.05 or 0.2 mg/mL rhBMP-2 delivered in an absorbable collagen sponge (ACS). At 8 weeks, dogs were euthanatized and bones were mechanically tested and examined by microscopy. RESULTS: Bone healing based on radiographic scoring, was significantly improved in dogs treated with 0.2 mg/mL of rhBMP-2 compared with the other groups; these tibiae were also significantly stronger and stiffer than 0.05 mg/mL rhBMP-2 and control osteotomized tibiae. Histologic scores were significantly better for 0.2 mg/mL rhBMP-2 group than 0.05 mg/mL rhBMP-2 group, but neither was significantly different from control. CONCLUSIONS: rhBMP-2 in ACS at a concentration of 0.2 mg/mL improves healing of tibial osteotomies in dogs compared with untreated controls and 0.05 mg/mL rhBMP-2 based on force plate analysis and radiographic evaluation. This was not confirmed histologically but treated bones had improved mechanical properties at 8 weeks. CLINICAL RELEVANCE: After a long bone fracture, dogs may face a long recovery period before full return of limb function. rhBMP-2, in association with good fracture fixation principles, may enhance bone healing in dogs with diaphyseal fractures.  相似文献   
97.
The prevalence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies was investigated in goats slaughtered in the public slaughterhouse of Patos, State of Paraíba, Northeast region of Brazil, and possible associations between sex of the animals and antibody prevalence were verified. Three-hundred six blood samples from goats collected before slaughter by jugular venopuncture were used. For the serologic diagnosis of T. gondii and N. caninum, the indirect fluorescent-antibody test (IFAT) with cut-off values 64 and 50, respectively, was carried out. The prevalence of anti-T. gondii antibodies was 24.5% [95% CI=19.8-29.7%] with titers ranging from 64 to 4096, and anti-N. caninum antibodies was 3.3% (95% CI=1.6-5.9%) with titers ranging from 50 to 400. There were no associations between sex of animals and prevalence of anti-T. gondii and anti-N. caninum antibodies.  相似文献   
98.
Carotenoids are pigments responsible for the yellow-reddish color of many foods and are related to important functions and physiological actions, preventing several chronic-degenerative diseases. The objective of this study was to confirm the carotenoid composition of jackfruit by high-performance liquid chromatography connected to photodiode array and mass spectrometry detectors (HPLC-PDA-MS/MS). The main carotenoids were all-trans-lutein (24–44%), all-trans-β-carotene (24–30%), all-trans-neoxanthin (4–19%), 9-cis-neoxanthin (4–9%) and 9-cis-violaxanthin (4–10%). Either qualitative or quantitative differences, mainly related to the lutein proportion, were found among three batches of jackfruit. Since the fruits from batch A showed significantly lower contents for almost all carotenoids, it also had the lowest total carotenoid content (34.1 μg/100 g) and provitamin A value, whereas the total carotenoid ranged from 129.0 to 150.3 μg/100 g in the other batches. The provitamin A values from batches B and C were 3.3 and 4.3 μg RAE/100 g, respectively. The carotenoid composition of jackfruit was successfully determined, where 14 of the 18 identified carotenoids were reported for first time. Differences among batches may be due to genetic and/or agricultural factors.  相似文献   
99.
On‐board Brazilian sardinella (Sardinella brasiliensis) conservation system based on cooling in ice, but in recent years, fishing boats have been applying immersion in chilled brine as a storage system on‐board. This study evaluated this system concerning physicochemical quality (total volatile bases, pH, histamine, moisture) of the fish and cation concentrations. Offshore (on‐board) data were collected (total storage time, over time temperature, fish mass captured by bid, load capacity in use and available) to assess the efficiency and viability. The results showed that this system is useful in maintaining the physicochemical quality of the fish since the samples met the quality standards required by law. Data showed high levels of sodium in fish muscle, which are strongly influenced by the immersion time, suggesting the need for standardization of the method considering the risks associated with consumption of foods with high levels of sodium.  相似文献   
100.
The objective of this work was to adapt the FT Raman spectroscopy analysis in the differentiation of haploid and diploid kernels in maize, developing a new efficient, agile, precise, and nondestructive methodology. The main difference observed in FT Raman readings was a peak in the region between 1600 and 1700 cm−1 in possibly haploid kernels. It was possible to correlate the characteristics of the kernels with the presence of the R1-nj gene and the readings obtained in the Raman spectrometry technique. Most of the kernels previously classified as haploid showed positive values for principal component analysis (PCAs), indicating a correlation in the identification of haploids by the techniques adopted. The identification of haploids by R-Navajo was superior to FT Raman. However, FT Raman spectroscopy is an agile analysis technique that enables the development of non-invasive and non-destructive analytical methods in maize kernels, in addition to providing relevant information about the chemical structures present in the composition of the samples.  相似文献   
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