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排序方式: 共有521条查询结果,搜索用时 15 毫秒
501.
Lilenbaum W de Souza GN Ristow P Moreira MC Fráguas S Cardoso Vda S Oelemann WM 《Veterinary journal (London, England : 1997)》2007,173(2):408-412
In spite of the large number of goats found in several developing tropical countries, milk production remains unsatisfactory. The occurrence of infectious diseases, such as leptospirosis, brucellosis and caprine arthritis-encephalitis (CAE) may in part be responsible for sub-optimal production. In this study, 1000 serum samples were tested for leptospirosis, 953 for brucellosis and 562 for CAE. All tested flocks presented at least one seroreactive animal for leptospirosis and for CAE. Reactivity to leptospirosis was 11.1%, and serovar hardjo was the most frequently found. Anti-B. abortus agglutinins were found in 0.5% of the samples presented and 14.1% were seroreactive to CAE. Leptospirosis was considered to represent the major infectious problem in the studied goat flocks. The occurrence of infectious diseases in the tested flocks may represent an important factor contributing to the decreased productivity of the animals. These findings may be similar to those observed in other developing countries and require further study to define the relationship between seropositivity and reduced production. 相似文献
502.
Valencia Echavarria Diana Marcela Giraldo Valderrama Luis Alfonso Marín Gómez Alejandra 《Tropical animal health and production》2020,52(2):565-571
Tropical Animal Health and Production - The aim of this trial was to determine the effect of ruminal fluid adapted to crude glycerol supplementation on in vitro methane and fermentation parameters... 相似文献
503.
Joao H.N. Soares Christina Braun Marcela L. Machado Renato L. Oliveira Natalia Henao-Guerrero Sherryl Countermash-Ott Irving C. Allen David C. Grant Antonio Giannella-Neto 《Veterinary anaesthesia and analgesia》2021,48(3):324-333
ObjectivesTo compare pulmonary gas exchange, tissue oxygenation and cardiovascular effects of four levels of end-expiratory pressure: no positive end-expiratory pressure (ZEEP), positive end-expiratory pressure (PEEP) of maximal respiratory system compliance (PEEPmaxCrs), PEEPmaxCrs + 2 cmH2O (PEEPmaxCrs+2), PEEPmaxCrs + 4 cmH2O (PEEPmaxCrs+4), in isoflurane-anesthetized dogs.Study designProspective randomized crossover study.AnimalsA total of seven healthy male Beagle dogs, aged 1 year and weighing 10.2 ± 0.7 kg (mean ± standard deviation).MethodsThe dogs were administered acepromazine and anesthesia was induced with propofol and maintained with isoflurane. Ventilation was controlled for 4 hours with ZEEP, PEEPmaxCrs, PEEPmaxCrs+2 or PEEPmaxCrs+4. Cardiovascular, pulmonary gas exchange and tissue oxygenation data were evaluated at 5, 60, 120, 180 and 240 minutes of ventilation and compared using a mixed-model anova followed by Bonferroni test. p < 0.05 was considered significant.ResultsCardiac index (CI) and mean arterial pressure (MAP) were lower in all PEEP treatments at 5 minutes when compared with ZEEP. CI persisted lower throughout the 4 hours only in PEEPmaxCrs+4 with the lowest CI at 5 minutes (2.15 ± 0.70 versus 3.45 ± 0.94 L minute–1 m–2). At 180 and 240 minutes, MAP was lower in PEEPmaxCrs+4 than in PEEPmaxCrs, with the lowest value at 180 minutes (58 ± 7 versus 67 ± 7 mmHg). Oxygen delivery index (DO2I) was lower in PEEPmaxCrs+4 than in ZEEP at 5, 60, 120 and 180 minutes. Venous admixture was not different among treatments.Conclusion and clinical relevanceThe use of PEEP caused a transient decrease in MAP and CI in lung-healthy dogs anesthetized with isoflurane, which improved after 60 minutes of ventilation in all levels of PEEP except PEEPmaxCrs+4. A clinically significant improvement in arterial oxygenation and DO2I was not observed with PEEPmaxCrs and PEEPmaxCrs+2 in comparison with ZEEP, whereas PEEPmaxCrs+4 decreased DO2I. 相似文献
504.
Jeremy Hansford Natalia Henao-Guerrero Marcela L. Machado Bruno H. Pypendop 《Veterinary anaesthesia and analgesia》2021,48(4):509-516
ObjectiveTo describe the pharmacokinetics of buprenorphine in dogs following administration of a high-concentration formulation of buprenorphine.Study designProspective, randomized, crossover study.AnimalsA total of six healthy male intact Beagle dogs, aged 9–13 months and weighing 10.3 ± 1.4 kg (mean ± standard deviation).MethodsDogs were randomized to be administered buprenorphine (0.12 mg kg–1; Simbadol, 1.8 mg mL–1) via the intravenous (lateral saphenous) or subcutaneous (dorsal interscapular) route followed by the alternative route of administration after a 14 day interval. Blood was sampled before administration and at set times up to 72 hours after injection. Plasma buprenorphine concentration was measured using liquid chromatography–tandem mass spectrometry.ResultsA three-compartment model with zero or biphasic rapid and slow first-order input in (intravenous or subcutaneous data, respectively) and first-order elimination from the central compartment best fitted the data. The rapid first-order input accounted for 63% of the dosage absorption. Typical values (% interindividual variability) for the three compartment volumes were 900 (33), 2425 (not estimated) and 6360 (28) mL kg–1. The metabolic and two distribution clearances were 25.7 (21), 107.5 (74) and 5.7 (61) mL minute–1 kg–1. The absorption half-life for the fast absorption phase was 8.9 minutes with a 0.7 (103) minute delay. The absorption half-life for the slow absorption phase was 347 minutes with a 226 (42) minute delay. Median (range) bioavailability calculated from noncompartmental analysis was 143 (80–239)%. Calculated terminal half-life was 963 minutes.Conclusions and clinical relevanceThe high-concentration formulation of buprenorphine administered subcutaneously had a large volume of distribution and a rapid absorption phase followed by slower, delayed absorption. The high estimate of bioavailability should be interpreted with caution as values above 100% are most commonly related to experimental issues. 相似文献
505.
Ricardo Calado Rui Rosa Sofia Morais Maria Leonor Nunes & Luís Narciso 《Aquaculture Research》2005,36(5):493-504
The present work evaluated the effect of three inexpensive diets (frozen minced mussel and edible cockle (MMC), frozen minced squid (MS) and gilthead seabream feed (GSF)) on growth, survival, sex reversal, lipid classes and fatty acid (FA) profile of juvenile ornamental shrimp Lysmata seticaudata. Shrimp fed GSF displayed the highest survival rate (±SD) (85.2±1.8%) and the highest percentage (±SD) of shrimp changing from male to simultaneous hermaphrodite (SH) phase (25.2±2.2%). All diets promoted growth rates superior to those reported in the wild, with SH shrimp displaying higher total lengths (TL). Shrimp in SH phase fed GSF displayed the highest TL (±SD) (40.6±1.2 mm). Cultured shrimp reflected the lipid content of experimental diets, with shrimp fed GSF displaying the highest triacylglycerols and sterols (ST) contents. The higher rearing density induced by lower mortality rates of shrimp fed GSF, and the high ST levels present in the diet, may explain the higher proportion of shrimp in SH phase. The higher levels of highly unsaturated fatty acids (HUFA) displayed by MS did not promote higher survival or growth rates. The low polyunsaturated fatty acids and HUFA content of MMC was not reflected in cultured shrimp, probably because of a selective retention of these FA. 相似文献
506.
João Gomes Cristina Lobo Vilela Ricardo Bexiga Gonçalo D Nunes Nuno Pereira & Lina M Cavaco 《Aquaculture Research》2007,38(6):613-617
Optimization of antibiotic delivery strategies to aquatic environment and to the specific characteristics of the target species is essential for the improvement of bacterial infection control measures. This work aimed at standardizing the use of Artemia salina to deliver flumequine to fish as antimicrobial treatment. Adult Artemia were used to bioencapsulate flumequine. A flumequine concentration of 358 μg mL−1 was found adequate to perform bioencapsulation during 24 h without causing mortality. Antibiotic concentration in Artemia, quantified by means of a microbiological assay based on MIC determination, using Escherichia coli ATCC 25922 as control strain was 256.55 mg g−1 (±71.22). The therapeutic doses of 10 mg kg−1 BW, calculated on the basis of a consumption of about 4% BW/day, would then be delivered by the consumption of 7.8 Artemia g−1 of fish. 相似文献
507.
Miguel Avendaño DÍAZ Marcela Cantillánez Silva Juan Peña Forner 《Aquaculture International》2006,14(3):267-283
A pilot program to evaluate the feasibility of collecting juvenile (seed) scallops using Japanese technology was carried out from October 2001 to April 2002 in the Marine Reserve at La Rinconada, Antofagasta, Chile. The continuous presence of larvae in waters in the reserve allowed for collection of 400–15,340 spat per collector and showed the high reproductive capability of local scallops and the relationship between numbers of larvae in the water and amount of spatfall. Highest rates of settlement were proportional to high numbers of umbone larvae in the water at >5000 larvae m−3 when collectors were first immersed. Absence of a relationship between larval numbers and postlarval settlement with trophic factors such as chlorophyll and particulate organic matter in the water suggests that productivity was not limited by these factors. Harvest of spat from collectors immersed for four and five months had recovery efficiencies of 5.5% and 59.4% compared with settlement in collectors after immersion for one month. Cohort analyses of recovered spat suggested that settlement occurred over the lengthy immersion period and was due to the continuous presence of larvae in the water. The loss of a high percentage of spat over the 4–5 immersion period compared with settlement in the first month can be attributed to intraspecific competition of spat density and growth as well as clogging of the collectors by sediment and marine fouling that impeded a flow of water through the nets. 相似文献
508.
Maria Alice Schnaider Henrique Mendonça Nunes Ribeiro-Filho Gilberto Vilmar Kozloski Tatiana Reiter Aline Cristina Dall Orsoletta Ademar Luiz Dallabrida 《Tropical animal health and production》2014,46(6):975-980
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. 相似文献
509.