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401.
Leemans J Kirschvink N Bernaerts F Clercx C Cambier C Gustin P 《Veterinary journal (London, England : 1997)》2009,180(2):236-245
This study compared the duration and magnitude of the antispasmodic effects of salmeterol (SLM), salbutamol (SAL), ipratropium bromide (IB) and the combination of SAL and IB (SAL/IB) against carbachol-induced bronchoconstriction in healthy cats, and investigated the gain in efficacy using a two or fourfold increase in drug dosages. The drug regimens used were: (1) SLM 25 microg, SAL 100 microg, IB 20 microg and SAL/IB 100 microg/20 microg for bronchodilators delivered by a metered-dose inhaler (MDI); (2) SAL 3.75 mg and IB 62.5 microg for nebulised (NEB) medications. To monitor the bronchodilator effect, airway responsiveness was assessed at different time points using barometric whole-body plethysmography and calculation of the concentration of inhaled carbachol inducing a 300% increase of baseline Penh (enhanced pause), an estimator of airflow limitation. Maximum C-Penh300 was recorded 15 min after NEB SAL, IB MDI, NEB IB and 1h after SAL MDI and 4h after SLM MDI, respectively. C-Penh300 was significantly different from control values (without treatment) up to 24h for SLM MDI, 8h for IB MDI and 4h for other drugs. In terms of efficacy, SAL/IB MDI showed a synergistic antispasmodic effect at 15 min, 4h and 8h after administration. A fourfold increase of the initial dose of IB MDI and NEB IB significantly increased C-Penh300. Despite a fourfold dose increase, SLM displayed the weakest degree of bronchoprotection compared to other bronchodilators. The study provides evidence that inhaled bronchodilators are efficient at preventing muscarinic-induced bronchospasm in healthy cats and that SAL and IB appear to be short-acting bronchodilators in contrast to SLM. 相似文献
402.
Billy Nzau Matondo Micha?l Ovidio Jean-Claude Philippart Pascal Poncin 《Fisheries Science》2012,78(6):1173-1178
The gonadosomatic index at spawning, absolute fecundity, and egg size for the female sexual products as well as the density and consistency of semen for the male sexual products were examined in cultured Abramis brama?×?Blicca bjoerkna F1 hybrids and compared with the parental species at their first sexual maturity. Females ovulated under environmental conditions, and their eggs were weighed, counted and measured. Semen of males was macroscopically examined and spermatozoa counted using a hemocytometer. Results revealed that hybridization affected the quality of female and male gametes but with an overlap between hybrids and parents. The gonadosomatic index and fecundity were significantly lower than those of parental species. Egg sizes in hybrids showed a parental effect but to the benefit of hybrids. Semen of hybrids was more diluted which was classified into two groups: the white semen overlapping slightly with parents and the aqueous without any overlap with parents. Overlapped areas between hybrids and parents in term of quality of sexual products could translate that females and males of these hybrids have the biological capacity to produce high quality gametes and thus, a greater chance to produce F2 and backcross generations in rivers. 相似文献
403.
Elie Montchowui Philippe Lalèyè Emile N'tcha Jean‐Claude Philippart Pascal Poncin 《Aquaculture Research》2012,43(8):1243-1250
This study aimed at (1) evaluating the efficacy of live food organisms (Artemia and natural zooplankton) and an artificial diet in the larval rearing of African carp Labeo parvus and (2) determining appropriate rearing conditions. After yolk sac resorption, the larvae were separated into five different feeding trials with two replicates. At the end of the larval rearing period (28 days post‐hatching), the highest (94.6%) and the lowest (53.7%) cumulative survival rates were found when larvae were fed with natural zooplankton for 7 days followed by Nippai food for 21 days, and when larvae were fed from the beginning of exogenous feeding with Nippai food only respectively. The significant highest body weight (351.6 mg), total length (34.4 mm) and specific growth rates (15.5%day?1) were recorded when the larvae were fed with Artemia nauplii for 14 days followed by Nippai food for 14 days. The lowest growth performance (body weight and specific growth rates) were obtained when larvae were fed exclusively Nippai food. These results indicate that L. parvus can be successfully cultured in indoor nursery systems from hatching to the early juvenile stage. 相似文献
404.
Ioannis E. Papadakis Stavros Chatzifotis Pascal Divanach Maroudio Kentouri 《Aquaculture International》2008,16(1):13-25
The weaning of greater amberjack (Seriola dumerilii Risso 1810) to a dry diet was studied in two consecutive experiments. The experimental fish were hatchery-produced and grown
to their initial size on a soft pellet containing 50% trash fish and 50% commercial dry pellet. In the first experiment, three
homogenous groups of greater amberjacks (n = 153, mean weight: 374 ± 43 g), initially adapted for a period of 30 days to a diet with a 40% moisture content, were fed
on commercial pellets containing three different levels of dietary moisture (7, 20 and 40%, respectively) for 126 days. We
found that fish needed a month to adapt to the 7%- and 20%-moisture diets and that moisture content of the diet had a significant
effect on fish growth in terms of increasing feed consumption and lowering feed conversion ratio. The group fed on the 20%-moisture
diet not only compensated for the initial adaptation period but presented the higher growth rate and best feed conversion
ratio. In the second experiment, all groups of experiment 1 were fed the same commercial diet with a 7% moisture content for
72 days. The group that had been previously fed on the 20%-moisture diet showed the best growth performance. The implication
of the above results for the weaning of greater amberjack to dry diets is discussed in terms of the digestion process and
physiology. 相似文献