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71.
Antinociceptive effect and acute toxicity of the Hyptis suaveolens leaves aqueous extract on mice 总被引:1,自引:0,他引:1
Santos TC Marques MS Menezes IA Dias KS Silva AB Mello IC Carvalho AC Cavalcanti SC Antoniolli AR Marçal RM 《Fitoterapia》2007,78(5):333-336
The aqueous extract of Hyptis suaveolens leaves was studied for their antinociceptive property in chemical and thermal models of nociception in mice. Oral administration of the aqueous extract (100, 200, and 400 mg/kg) dose-dependently reduced the number of writhings induced by acetic acid, decreased the licking activity of the early phase in formalin test and increased the reaction time in hot-plate test. The antinociceptive effect was significantly antagonized by naloxone (3 mg/kg; i.p.). Preliminary acute toxicity study showed that no animal death with doses up to 5 g/kg (p.o.). 相似文献
72.
Interest in magnetic resonance (MR) imaging as a major diagnostic tool in veterinary clinical medicine is increasing. Most MR studies are performed with the use of contrast enhancement via intravenous injection of paramagnetic gadolinium-containing contrast media. A vast number of publications are available regarding the use of contrast media in humans. The purpose of this paper is to assist practicing veterinary radiologists in understanding mechanisms of MR contrast enhancement. This paper reviews certain aspects of MR contrast enhancement, including physical, chemical and biologic characteristics of most common MR contrast media targeted primarily at the central nervous system (CNS). Authors also describe processes that explain changes in signal intensity on the MR images. 相似文献
73.
DIAGNOSTIC SENSITIVITY OF ULTRASOUND,RADIOGRAPHY AND COMPUTED TOMOGRAPHY FOR GENDER DETERMINATION IN FOUR SPECIES OF LIZARDS 下载免费PDF全文
Francesco Di Ianni Antonella Volta Igor Pelizzone Sabrina Manfredi Giacomo Gnudi Enrico Parmigiani 《Veterinary radiology & ultrasound》2015,56(1):40-45
Gender determination is frequently requested by reptile breeders, especially for species with poor or absent sexual dimorphism. The aims of the current study were to describe techniques and diagnostic sensitivities of ultrasound, radiography, and computed tomography for gender determination (identification of hemipenes) in four species of lizards. Nineteen lizards of known sex, belonging to four different species (Pogona vitticeps, Uromastyx aegyptia, Tiliqua scincoides, Gerrhosaurus major) were prospectively enrolled. With informed owner consent, ultrasound, noncontrast CT, contrast radiography, and contrast CT (with contrast medium administered into the cloaca) were performed in conscious animals. Imaging studies were reviewed by three different operators, each unaware of the gender of the animals and of the results of the other techniques. The lizard was classified as a male when hemipenes were identified. Nineteen lizards were included in the study, 10 females and nine males. The hemipenes were seen on ultrasound in only two male lizards, and appeared as oval hypoechoic structures. Radiographically, hemipenes filled with contrast medium appeared as spindle‐shaped opacities. Noncontrast CT identified hemipenes in only two lizards, and these appeared as spindle‐shaped kinked structures with hyperattenuating content consistent with smegma. Hemipenes were correctly identified in all nine males using contrast CT (accuracy of 100%). Accuracy of contrast radiography was excellent (94.7%). Accuracy of ultrasound and of noncontrast CT was poor (64.3% and 63.1%, respectively). Findings from the current study supported the use of contrast CT or contrast radiography for gender determination in lizards. 相似文献
74.
It is important to predict how many individuals of a predator species can survive in a given area on the basis of prey sufficiency and to compare predictive estimates with actual numbers to understand whether or not key threats are related to prey availability. Rugged terrain and low detection probabilities do not allow for the use of traditional prey count techniques in mountain areas. We used presence–absence occupancy modeling and camera‐trapping to estimate the abundance and densities of prey species and regression analysis to predict leopard (Panthera pardus) densities from estimated prey biomass in the mountains of the Nuvadi area, Meghri Ridge, southern Armenia. The prey densities were 12.94 ± 2.18 individuals km?2 for the bezoar goat (Capra aegagrus), 6.88 ± 1.56 for the wild boar (Sus scrofa) and 0.44 ± 0.20 for the roe deer (Capreolus capreolus). The detection probability of the prey was a strong function of the activity patterns, and was highest in diurnal bezoar goats (0.59 ± 0.09). Based on robust regression, the estimated total ungulate prey biomass (720.37 ± 142.72 kg km?2) can support a leopard density of 7. 18 ± 3.06 individuals 100 km?2. The actual leopard density is only 0.34 individuals 100 km?2 (i.e. one subadult male recorded over the 296.9 km2), estimated from tracking and camera‐trapping. The most plausible explanation for this discrepancy between predicted and actual leopard density is that poaching and disturbance caused by livestock breeding, plant gathering, deforestation and human‐induced wild fires are affecting the leopard population in Armenia. 相似文献
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Andressa Santanna Natel Adibe Luiz Abdalla Rafael Canonenco de Araujo Concepta McManus Tiago do Prado Paim Adibe Luiz de Abdalla Filho Patrícia Louvandini Carina Nazato 《Animal Science Journal》2019,90(10):1350-1361
The objective of this study was to evaluate the effects of using encapsulated nitrate product (ENP) replacing soybean meal in diets differing in concentrate to forage ratio on ruminal fermentation and methane production in vitro using a semi‐automatic gas production technique. Eight treatments were used in a randomized complete design with a 2 × 4 factorial arrangement: two diet (20C:80F and 80C:20F concentrate to forage ratio) and four levels of ENP addition (0%, 1.5%, 3.0%, and 4.5% of DM) replacing soybean meal. There was a diet × ENP interaction (p = 0.02) for methane production. According to ENP addition, diets with 80C:20F showed more intense reduction on methane production that 20C:80F. A negative linear effect was observed for propionate production with ENP addition in diet with 80C:20F and to the relative abundance of methanogens Archaea, in both diet. The replacement of soybean meal by ENP in levels up to 3% of DM inhibited methane production due to a reduction in the methanogens community without affecting the organic matter degradability. However, ENP at 4.5% of DM level affected fiber degradability, abundance of cellulolytic bacteria, and propionic acid production, indicating that this level of inclusion is not recommended for ruminant production. 相似文献
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Tiago S. Nascimento Isabelle S. M. Silva Maria Cecília M. A. Alves Bruna B. Gouveia Lara Mariane R. Barbosa Taís J. S. Macedo Jamile M. S. Santos Alane P. O. Monte Maria Helena T. Matos Francine F. Padilha Isabel B. Lima‐Verde 《Reproduction in domestic animals》2019,54(1):31-38
This study aimed to characterize the hydroethanolic extract of red propolis (HERP) and nanoparticles containing HERP for using as an additive in the culture medium of isolated ovine preantral follicles. HERP was characterized by high‐performance liquid chromatography (HPLC) and determination of flavonoid content, and the nanoparticles by the mean particle diameter, polydispersity index (PI) and encapsulation efficiency (EE). The effect of HERP (10 and 20 ηg/ml—HERP10 and HERP20 groups) and nanoparticles (NP10 and NP20 groups) on isolated secondary follicles cultured in vitro for 12 days was observed by morphological evaluation, oxidative stress markers (reactive oxygen species—ROS and glutathione—GSH) and active mitochondria. HPLC showed formononetin as the major compound in the HERP (63.92 ± 0.21 μg/mL). The content of flavonoids ranged from 2.14% to 11.00%. The nanoparticles showed mean diameter of 287.5 ± 3.9 and 479 ± 18.1 ηm; PI of 0.117 ± 0.018 and 0.316 ± 0.039; and EE of 67.15% and 41%, respectively, for the NP10 and NP20 groups. After 12 days of culture, HERP20 and NP20 increased (p < 0.05) the percentage of normal follicles compared to NP10. HERP20 showed significantly higher percentages of antrum formation than control medium (MEM) and NP10 (p < 0.05). HERP20 also showed an increase (p < 0.05) in mitochondrial activity compared to the other treatments, except NP20 (p > 0.05), and increased GSH levels (p < 0.05) compared to MEM and HERP10. In conclusion, use of HERP (20 ηg/ml) on in vitro culture of isolated ovine preantral follicles can increase antrum formation, mitochondrial activity and GSH levels. 相似文献
80.
Tiago Facury Moreira Rafael Romero Nicolino Leandro Silva de Andrade Elias Jorge Facury Filho Antônio Ultimo de Carvalho 《Tropical animal health and production》2018,50(8):1829-1834
Lameness is a growing concern to the dairy industry worldwide. However, little is known about lameness and its causes in grazing cattle, especially in tropical climates. This study aimed to assess the prevalence of hoof lesions and lameness in dairy herds of all year-round grazing cattle under tropical condition, and to identify the main lesions associated with lameness. We visited 48 farms located in the Minas Gerais state, Brazil, equally divided into four groups based on daily milk production. All lactating cows in the visited farms were locomotion scored, and a representative sample was randomly chosen for hoof inspection. Among the 2267 lactating cows evaluated, 16% were scored as lame and 7% as severely lame. Nearly all cows presented at least one type of hoof lesion, of which heel horn erosion (90%), white line fissure (50%), and digital dermatitis (33%) were the most prevalent. Heel horn erosion was present in all farms and digital dermatitis was present in 96% of the farms. Sole ulcer was observed in a single animal. Additionally, digital dermatitis and white line fissure were correlated to a 2.5 times increase in the odds of a poor mobility score. Collectively, our results demonstrate that digital dermatitis and white line fissure are the main concern and the biggest cause of lameness in grazing cattle under tropical conditions. 相似文献