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31.
ObjectiveTo evaluate the effects of dexmedetomidine alone or in combination with different opioids on intraocular pressure (IOP) in dogs.Study designExperimental, prospective, crossover, randomized, blinded study.AnimalsA total of six Beagle dogs (two males and four females) aged 2 years and weighing 15.9 ± 2.9 kg (mean ± standard deviation).MethodsDogs were distributed randomly into seven treatments (n = 6 per treatment) and were administered dexmedetomidine alone (10 μg kg–1; Dex) or in combination with butorphanol (0.15 mg kg–1; DexBut), meperidine (5 mg kg–1; DexMep), methadone (0.5 mg kg–1; DexMet), morphine (0.5 mg kg–1; DexMor), nalbuphine (0.5 mg kg–1; DexNal) or tramadol (5 mg kg–1; DexTra). All drugs were administered intramuscularly. IOP was measured before drug injection (time 0, baseline) and every 15 minutes thereafter for 120 minutes (T15–T120).ResultsThere were significant reductions in IOP compared with baseline in treatments Dex and DexMep at times T30–T120, and in treatment DexMet at T15–T90. IOP decreased compared with baseline in treatments DexBut, DexNal and DexTra at all evaluation times. No changes in IOP were seen in treatment DexMor. The mean IOP values in treatment DexMet at T105–T120 were higher than those for other treatments.Conclusions and clinical relevanceDexmedetomidine alone or in combination with butorphanol, meperidine, methadone, nalbuphine or tramadol resulted in decreased IOP for 120 minutes in dogs. The magnitude of the reduction was small and lacked clinical significance.  相似文献   
32.
The total phenolic, flavanol, monomeric anthocyanin contents and the antioxidant activity of flesh and peel of 11 apple cultivars from Brazil were investigated. Concentrations of the parameters measured differed significantly among the apple cultivars and were highest in the peel compared to the flesh. Total phenolic content (mg GAE/100 g fresh matter) ranged from 128.3 (Golden Delicious) to 212.0 (Epagri-F5P283) in the flesh and 304.6 (Golden Delicious) to 712.6 (Catarina) in the peel. Total flavanol content (mg CAE/100 g fm) varied from 11.7 (Epagri-SJ11) to 28.2 (Epagri-F43P23) and from 32.4 (Epagri-SJ11) to 147.7 (Catarina) in the flesh and peel, respectively. COOP-24 peel had the highest total anthocyanin content. The Epagri-F5P283 and Epagri-F43P23 flesh and Catarina peel had the highest antioxidant activity while Golden Delicious flesh and peel had the lowest. The total phenolic content and antioxidant activity were significantly correlated in both flesh (R2 = 0.717) and peel (R2 = 0.716). The contribution of phenolics to the antioxidant activity in peel suggests that their removal may induce a significant loss of antioxidants.  相似文献   
33.
Copepods have a number of advantages for use as live food in cultures of fish and crustacean larvae. This study aimed to develop culture techniques of Tisbe biminiensis Volkmann‐Rocco 1973 in volumes of 500 mL. The first experiment tested the effect of salinity on survival and fecundity. The other experiments studied the population growth comparing two levels of daily ration and the effect of sand sediment in cultures. The cultures were carried out on plastic boxes at 29°C, salinity of 34 g L?1 and 12 h light/12 h dark photoperiod with aerated filtered seawater, total renewal every other day. Adult females tolerated the decrease of salinity from 34 to 27 g L?1 but the offspring production decreased significantly. The salinity of 20 g L?1 was not tolerated at all. Tisbe biminiensis attained one of the highest rates of increase in cultures among harpacticoids (0.33 day?1) and a high density of 205 individual ind. mL?1. The carrying capacity of the population was estimated as 67 200 ind. in 500 mL recipients. In conclusion, T. biminiensis grow fast and attain high densities in cultures of 500 mL volume without sediment, feeding a daily ration of 50–100% of copepodite biomass.  相似文献   
34.
The objective of this study was to evaluate the effects of supplying the by-product of peach-palm (Bactris gasipaes) on performance and characteristics of carcass and non-carcass components of feedlot lambs. Twenty Santa Ines lambs of 150 days average age and 22.4?±?3.4 kg body weight were confined in individual pens. A completely randomized design was utilized with four experimental diets composed of: fresh peach-palm by-product enriched with urea, fresh peach-palm by-product + concentrate, silage of peach-palm by-product + concentrate, and silage of peach-palm by-product enriched with 15 % corn meal + concentrate. Intake was evaluated daily, and at the end of 42 days of experiments, lambs were slaughtered and the characteristics of carcass and non-carcass parts were evaluated. Performance and carcass characteristics showed differences between the animals’ intake of total mixed rations (TMR) and only the diet with roughage. For the lambs that intaked TMR, the form of utilization of roughage (fresh or as silage) affected animal performance but did not change the carcass characteristics. Dry matter intake and feed conversion were influenced by the form of utilization of the silage (with and without additive). Providing fresh by-product plus concentrate improves lamb performance but does not interfere in the carcass characteristics, compared with the use of by-product in the form of silage.  相似文献   
35.
A concomitant study was carried out, of the association of positive serology for Toxocara spp. in 90 children who played in public squares used for leisure, with the frequency with which each child used these areas, and the presence of eggs of Toxocara spp. in the sand or grass in these locations. The sand and grass of their peridomiciles and school playgrounds, as well as the feces of their dogs were also analyzed for Toxocara. Serum samples were tested for IgG antibodies to Toxocara canis excreted-secreted larval antigens by ELISA, and blood samples for eosinophilia. The water-sedimentation technique was used to evaluate the presence of parasite eggs in the sand and grass turfs, and in feces of the dogs that also frequented these locations. 16/90 (17.8%) of the children were seropositive for Toxocara spp. There was a positive association between seropositivity in children who played in the public squares six or seven times a week, with a parasite load above 1.1 eggs/g of sand, as well as with contamination of the peridomicile, even at less than 1.0 egg/g of sand. Eosinophilia, the habit of geophagy, age from one to four years, and the presence of parasitized pet dogs were also positively correlated with seropositivity in the children. Eggs were found in 15/15 (100%) of the public squares, 17/90 (18.9%) of the peridomiciles, 3/13 (23.1%) of the schools, and 12/41 (29.3%) of the dogs living in the peridomiciles investigated.  相似文献   
36.
The choice of planting density and tree genotype are basic decisions when establishing a forest stand. Understanding the interaction between planting density and genotype, and their relationship with biomass production and potential water stress, is crucial as forest managers are faced with a changing climate. However, few studies have investigated this relationship, especially in areas with highly productive forests. This study aimed to determine the interaction between biomass production and leaf water potential, as a surrogate of potential water stress, in different clonal Eucalyptus genotypes across a range of planting densities. Four clones (two clones of E. urophylla × E. grandis, one clone of E. urophylla, and one clone of E. grandis × E. camaldulensis) and four planting densities (ranging from 591 to 2 949 trees ha?1) were evaluated in an experimental stand in south-eastern Brazil. Biomass production was estimated 2.5 years after planting and predawn (ψpd) and midday (ψmd) leaf water potential were measured 2 and 2.5 years after planting, in February (wet season) and August (dry season) in 2014. For all clones, total stand stemwood biomass production increased and leaf water potential decreased with planting density, and their interaction was significant. Thus, wood biomass at tighter spacings was higher but exhibited lower leaf water potentials, resulting in a trade-off between productivity and potential water stress. These are preliminary findings and still need to be supported by more experimental evidence and repetitions. However, in light of the increased frequency of extreme climate events, silvicultural practices that are tailored to the potential productivity of each region and that result in low potential water stress should be considered.  相似文献   
37.
This study aimed to evaluate the vitellogenic transference and incorporation of long‐chain polyunsaturated fatty acids (LC‐PUFA) into the membranes of Prochilodus lineatus embryos, aiming to increase the permeability to cryoprotectants and resistance to electric fields. One hundred thirty broodstock of P. lineatus were fed with control (C) or fish oil‐supplemented diets (FO) for 12 months. The fatty acid (FA) profle was determined using gas chromatography. For the neutral fraction, the FO group had a decrease in monounsaturated fatty acids (MUFA) and an increase in n3PUFA and, n6PUFA. To test for cryoprotectant toxicity, embryos were exposed for 20 min to a cryoprotectant solution of 1,2‐Propanediol (Prop) at a concentration of 5 or 6 molar (M). For FO, a reduction in survival of 33.1% was observed in 5 M, and no survival was observed at 6 M. Embryo samples were exposed the six polarized electric fields (3.4–51.6 joules), and with 11.2 J of energy, the control group exhibited reduced survival in 98.3% of the fish, whereas the FO presented superior resistance, exhibiting a survival similar to that of the OJ up to 40.2 J. We conclude that FA were transferred between P. lineatus broodstock to the embryos, with an increase in LC‐PUFA resulting in lower survival rates in the cryoprotectant test in the FO group and a greater physical plasticity of FO embryos to electrical field tests.  相似文献   
38.
The aim of this work was to evaluate the chemical properties of the residues from erva-mate processing and also to determine the candy-making performance with addition of residues from erva-mate on consumers' acceptance and purchase intent of this new product. The candies containing different amounts of mate powder were evaluated through overall acceptability test and purchase intent. Mate powder showed high contents of dietary fiber, total ash, and total polyphenols. The total dietary fiber content of the mate candies ranged from 5.7 to 6.29% on a dry matter basis. Supplementation with mate powder caused significant increases in polyphenol and mineral contents of mate candies. The incorporation of mate powder increased the hardness of the candies and produced desirable results in their nutritional characteristics. The sensory tests indicated that mate candies were acceptable and approved in relation to purchase intent.  相似文献   
39.
Silicon (Si) can increase phosphorus (P) use efficiency (PUE) by increasing P availability in the soil and altering P metabolism in the plant, thus resulting in improved yield under low soil P conditions. The objective was to evaluate the effect of P (10, 50, 100, and 200?mg dm?3) and Si (0, 50, and 200?mg dm?3) interrelationship on P and Si uptake by plants, forms of P in leaves and tubers, plant growth, and tuber yield of potato plants. Silicon supply increased organic and inorganic P in the leaves. At low soil P rates, Si also increased organic P in the tubers. However, alterations in the P metabolism of potato plants with Si supply did not promote significant changes in dry matter (DM) production and tuber yield. Phosphate fertilization increased growth and yield of plants. Silicon uptake by the plants were also increased by phosphate fertilization with soil Si supply.  相似文献   
40.
Corneal degeneration may occur with a deposition of lipids or calcium, or both. Calcareous and lipid degeneration may be either primary or secondary, associated with systemic diseases such as primary hyperlipidemia, hyperlipidemia associated with hyperadrenocorticism, and hypothyroidism. The authors report a case of bilateral corneal lipid and calcium degeneration in a 7-year-old female Poodle with hyperadrenocorticism. The condition worsened with Lysodren therapy but responded to surgical excision.  相似文献   
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