Cyclooxygenases 1 and 2 inhibition and analgesic efficacy of dipyrone at different doses or meloxicam in cats after ovariohysterectomy

ObjectiveTo evaluate the cyclooxygenases (COX) inhibition, adverse effects and analgesic efficacy of dipyrone or meloxicam in cats undergoing elective ovariohysterectomy.Study designProspective, blinded, randomized, clinical study.AnimalsA total of 30 healthy young cats.MethodsThe cats were randomly assigned to three postoperative groups: D25 (dipyrone 25 mg kg^?1 every 24 hours), D12.5 (dipyrone 12.5 mg kg^?1 every 12 hours) and M (meloxicam 0.1 mg kg^?1 every 24 hours). In the first 24 hours, the drugs were administered intravenously (IV), and then orally for 6 (dipyrone) or 3 days (meloxicam). Prostanoids thromboxane B₂ and prostaglandin E₂ concentrations served as indicators of COX activity and, with physiological variables and pain and sedation scores, were measured for 24 hours after first analgesic administration. Rescue analgesia (tramadol, 2 mg kg^?1 IV) was provided if Glasgow feline composite measure pain scale (CMPS-Feline) ≥5. Laboratory tests included symmetric dimethylarginine and adverse effects were evaluated regularly up to 7 and 10 days after surgery, respectively. Parametric and nonparametric data were analyzed with two-way anova and Kruskal-Wallis tests, respectively (p < 0.05).ResultsIn the first half hour after analgesic administration, COX-1 activity was close to zero and remained significantly lower than before drug administration for 24 hours in all groups. The inhibition of COX-2 activity was significant for 30 minutes in all groups and up to 4 hours in group M. No alterations in laboratory tests or significant adverse effects were observed. Pain scores and need for rescue analgesia did not differ statistically among groups.ConclusionsDipyrone at both doses and meloxicam provided a nonselective inhibition of COX-1 and -2 activities and effective analgesia without causing significant adverse effects or laboratory tests alterations.Clinical relevanceDipyrone at both doses provides equally effective analgesia without causing adverse effects in cats undergoing ovariohysterectomy.     

Assessing possible effects of fish-culture systems on fish swimming: the role of stability in turbulent flows

Fish are cultured in ponds, recirculating systems, raceways, and cages. Turbulence is associated with one or more of mechanisms to facilitate food accessibility, maintain adequate levels of oxygen, remove carbon dioxide, urinary and fecal wastes, as well as from locomotion of fishes themselves. Turbulence has been shown to have positive and negative effects on fish swimming, feeding, and energetics, usually with negative impacts at very low and at high levels, and least effects and sometimes positive effects at intermediate levels. Differences in responses of fishes with varying levels of turbulence are related to the size of eddies relative to the size of a fish (larvae, juveniles, and adults). Impacts on locomotor functions are associated with eddy diameters of the order of 0.5–1L, where L is the total length of a fish. Negative locomotor impacts of turbulence are associated with eddies challenging stability, while positive effects promote drafting and station holding with reduced locomotor motions. Deployment of control surfaces increases with the level of turbulence up to a threshold where control is overwhelmed. The design of culture facilities is expected to affect levels of turbulence and may be engineered to provide optimal levels facilitating high growth.     

Intake and digestion of wethers fed with dwarf elephant grass hay with or without the inclusion of peanut hay

The aim of this study was to evaluate the effect of the inclusion of peanut (Arachis pintoi cv. Amarillo) hay in diets based on dwarf elephant grass (DEG, Pennisetum purpureum Schum cv. Kurumi) hay of different regrowth ages on forage intake and digestibility in wether lambs. The experimental treatments consisted of DEG hay with an interval of regrowth of 30 or 45 days offered as the only feed or in mixture with peanut hay (300 g/kg of total dry matter (DM)), which were tested in eight Texel?×?Suffolk crossbred wethers in a replicated 4?×?4 Latin square experiment. Both organic matter (OM) and digestible OM intakes were higher (P?<?0.05) in animals receiving the legume forage. Total apparent OM digestibility was higher (P?<?0.05) at an increased grass regrowth age. Ruminal OM digestibility increased (P?<?0.05) with legume inclusion and at a higher grass regrowth age. The nitrogen (N) intake was higher (P?<?0.05) in legume treatments and lower (P?<?0.05) as the grass regrowth age increased, but retention of N was not affected by treatments. Duodenal flow of both, non-ammonia N and microbial N, were not affected by legume inclusion and were lower (P?<?0.05) as grass regrowth age increased. The efficiency of rumen microbial protein synthesis (ERMPS) was negatively affected (P?<?0.05) by legume inclusion and was lower (P?<?0.05) as the grass regrowth age increased. Supplementation of dwarf elephant grass hay cut at the vegetative stage with peanut legume hay improves nutritional supply to wethers due to an increase in the forage intake.     

The transmission potential of Rift Valley fever virus among livestock in the Netherlands: a modelling study

Abstracts

Rift Valley fever virus (RVFV) is a zoonotic vector-borne infection and causes a potentially severe disease. Many mammals are susceptible to infection including important livestock species. Although currently confined to Africa and the near-East, this disease causes concern in countries in temperate climates where both hosts and potential vectors are present, such as the Netherlands. Currently, an assessment of the probability of an outbreak occurring in this country is missing. To evaluate the transmission potential of RVFV, a mathematical model was developed and used to determine the initial growth and the Floquet ratio, which are indicators of the probability of an outbreak and of persistence in a periodic changing environment caused by seasonality. We show that several areas of the Netherlands have a high transmission potential and risk of persistence of the infection. Counter-intuitively, these are the sparsely populated livestock areas, due to the high vector-host ratios in these areas. Culex pipiens s.l. is found to be the main driver of the spread and persistence, because it is by far the most abundant mosquito. Our investigation underscores the importance to determine the vector competence of this mosquito species for RVFV and its host preference.     

Mars surface diversity as revealed by the OMEGA/Mars Express observations

The Observatoire pour la Minéralogie, l'Eau, les Glaces, et l'Activité (OMEGA) investigation, on board the European Space Agency Mars Express mission, is mapping the surface composition of Mars at a 0.3- to 5-kilometer resolution by means of visible-near-infrared hyperspectral reflectance imagery. The data acquired during the first 9 months of the mission already reveal a diverse and complex surface mineralogy, offering key insights into the evolution of Mars. OMEGA has identified and mapped mafic iron-bearing silicates of both the northern and southern crust, localized concentrations of hydrated phyllosilicates and sulfates but no carbonates, and ices and frosts with a water-ice composition of the north polar perennial cap, as for the south cap, covered by a thin carbon dioxide-ice veneer.     

Early seedling establishment of two tropical montane cloud forest tree species: The role of native and exotic grasses

Tropical montane cloud forest has been undergoing a drastic reduction because of its widespread conversion to pastures. Once these forests have been cleared exotic grasses are deliberately introduced for forage production. Exotic grass species commonly form monodominant stands and produce more biomass than native grass species, resulting in the inhibition of secondary succession and tree regeneration. The purpose of this study was to assess the effect of native vs. exotic grass species on the early establishment of two native tree seedlings (Mexican alder, Alnus acuminata and Jalapa oak, Quercus xalapensis) on an abandoned farm in central Veracruz, Mexico. Seedling survival and growth were monitored (over 46 weeks) in relation to grass cover and height, and available photosynthetic active radiation (PAR). More seedlings survived in the presence of the native grass Panicum glutinosum than those growing with the exotic grass Cynodon plectostachyus (92% vs. 48%). The causes of seedling mortality varied between species; Q. xalapensis was affected by herbivory by voles but mainly in the exotic grass-dominated stands, whereas A. acuminata seedlings died due to competition with the exotic grass. A. acuminata seedlings increased more in height in the exotic grass-dominated stands (102 ± 7.8 cm) compared to native grass-dominated stands (51 ± 4.7 cm). Grass layer height, cover and available PAR were correlated (Pearson; p < 0.05). In the exotic grass dominated plots, grass layer height was correlated with the relative height growth rates of Q. xalapensis (Pearson; p < 0.05). These results indicate that the exotic grass may be affecting tree regeneration directly (grass competition) and indirectly (higher herbivory). Passive restoration may occur once P. glutinosum dominated pastures are abandoned. However, when C. plectostachyus dominates, introduction of early and mid successional tree seedlings protected against vole damage is needed.     

Strategies of supplementation of female suckling calves and nutrition parameters of beef cows on tropical pasture

The performance of female calves in creep feeding under different strategies of supplementation and milk production, intake, and digestibility of grazing Nellore and crossbred cows (Nellore?×?Holstein) during the dry-rainy transition season were assessed. Forty-four female beef suckling calves, with initial age between 90 and 150?days and average initial body weight of 117.7?±?4.3?kg, and their respective dams (24 Nellore and 20 crossbred) with average initial body weight of 417.5?±?8.3?kg, were used. The experimental treatments consisted of: control group-mineral mixture only; strategy 1-supplementation from 112?days prior to weaning (0.375?kg/animal/day); strategy 2-supplementation from 112?days prior to weaning, in increasing amounts of 0.15, 0.30, 0.45, and 0.60?kg/animal/day through the four experimental periods, respectively; and strategy 3-supplementation from 56?days prior to weaning (0.750?kg/animal/day). Calves from strategy 1 had greater (P??0.05) for nutrient digestibility among genetic types. It can be concluded that strategies of supplementation that present an equitable distribution of supplement provides greater weight gain in suckling female beef calves. Crossbred cows produce more milk and present greater DMI than Nellore cows. There are no differences in the nutrient digestibility between Nellore and Nellore × Holstein crossbred cows.