José Ramón Rodríguez Pérez

Clinical efficacy of anti-pneumococcal vaccination in patients with COPD

Background: A study was undertaken to evaluate the clinical efficacy of the 23-valent pneumococcal polysaccharide vaccine (PPV) in immunocompetent patients with chronic obstructive pulmonary disease (COPD). Methods: A randomised controlled trial was carried out in 596 patients with COPD of mean (SD) age 65.8 (9.7) years, 298 of whom received PPV. The main outcome was radiographically proven community acquired pneumonia (CAP) of pneumococcal or unknown aetiology after a mean period of 979 days (range 20–1454). Results: There were 58 first episodes of CAP caused by pneumococcus or of unknown aetiology, 25 in the intervention group and 33 in the non-intervention group. Kaplan-Meier survival curves for CAP did not show significant differences between the intervention and non-intervention arms (log rank test = 1.15, p = 0.28) in the whole group of patients. The efficacy of PPV in all patients was 24% (95% CI −24 to 54; p = 0.333). In the subgroup aged <65 years the efficacy of PPV was 76% (95% CI 20 to 93; p = 0.013), while in those with severe functional obstruction (forced expiratory volume in 1 second <40%) it was 48% (95% CI −7 to 80; p = 0.076). In younger patients with severe airflow obstruction the efficacy was 91% (95% CI 35 to 99; p = 0.002). There were only five cases of non-bacteraemic pneumococcal CAP, all in the non-intervention group (log rank test = 5.03; p = 0.025). Multivariate analysis gave a hazard ratio for unknown and pneumococcal CAP in the vaccinated group, adjusted for age, of 0.20 (95% CI 0.06 to 0.68; p = 0.01). Conclusions: PPV is effective in preventing CAP in patients with COPD aged less than 65 years and in those with severe airflow obstruction. No differences were found among the other groups of patients with COPD.

The possibilities for artificial incubation of white-clawed crayfish (Austropotamobius pallipes Lereboullet) eggs: comparison between maternal and artificial incubation

Abstract The development of artificial incubation techniques for freshwater crayfish eggs and the incorporation of these practices to the working scheme in production centres would have numerous advantages. This study evaluates the efficacy of one particular device, designed by this research group, for the artificial incubation of white-clawed crayfish ( Austropotamobius pallipes ) eggs. Comparisons between maternal and artificial incubation demonstrated the suitability of the tested system for artificial incubation for eggs of this species, during a period of 42% of the total duration of the embryonic development. Overall survival rate to juvenile stage 2 was significantly higher ( P

Effects of shelter type and food supply frequency on survival and growth of stage-2 juvenile white-clawed crayfish (Austropotamobius pallipes Lereboullet) under laboratory conditions

Two shelter substrates (fibre-cement sheets and PVC pipes) and two foodsupply frequencies (once and twice daily) were tested on white-clawed juvenilecrayfish in two separate experiments performed under laboratory conditions.Juvenile crayfish were maintained at an initial density of 50 animals persquaremetre in a flow-through system and fed on fresh Daphniapulex and a feed formulated for rainbow trout. After 120 days,highersurvival (50.5%), but lower growth, was obtained when fibre-cement sheets wereprovided as shelter. A comparison between food supply frequencies showed abetter survival rate (60.5%) when food was provided twice per day althoughtherewere no differences in growth after 80 days of trial. The number of animalswith chela autotomy is positively correlated (r between 0.33 and 0.48 depending ontreatments) with decreases in survival rate. The combination of adequate shelterand frequency of food supply could reduce the agonistic behaviour of juvenilecrayfish.

Effects of different thermal treatments during embryonic development on the artificial incubation efficiency of crayfish (Austropotamobius pallipes Lereboullet) eggs. Control of the embryogenetic duration and implications for commercial production

Summary The development and improvement of artificial incubation techniques for freshwater crayfish eggs and their incorporation into the working schedule of breeding centres is of great interest for commercial production. Factors such as the water circulation system, flow rate, thermal treatment, etc., could strongly influence the success of the process. The present study attempts to test the possible influence of one of these variables, the thermal regime, on both the duration of embryonic development and the efficiency rates obtained in the artificial incubation of white-clawed crayfish (Austropotamobius pallipes) eggs. Four different thermal treatments were tested (three of them included a period at low temperature: 4°-5°C). Survival rates to juvenile stage 2 were similar in the four cases, ranging between 66.7 and 72.7%. We conclude that water cooling (an expensive management procedure) is not necessary in astacid breeding centres provided that egg development takes place at moderately low temperatur...

EFFECTS OF DIFFERENT THERMAL TREATMENTS ON THE MATERNAL INCUBATION EFFICIENCY OF THE ASTACID CRAYFISH AUSTROPOTAMOBIUS PALLIPES (LEREBOULLET,1858) UNDER CONTROLLED CONDITIONS

[Adult freshwater crayfish, Austropotamobius pallipes, were maintained in the laboratory in such a way that mating, spawning, and maternal egg incubation took place under controlled conditions. This allowed to obtain data on reproductive biology from spawning to stage 2 juveniles. Three different thermal treatments were tested during embryonic development: a constant temperature of 11°C, ambient room temperature, and the incorporation of a cold period (3 weeks at 4°C). Females used in the three treatments tested were of a similar size (Mean Carapace Length ± Mean Standard Error = 34.06 ± 0.11 mm). Stage 2 juvenile production was not significantly different among the three regimes applied. The highest mean number of stage 2 juveniles per female (23) was obtained in animals maintained at constant temperature. Statistical differences were not detected, neither with regard to reproductive efficiency, in which the best value (33%) again was obtained at constant temperature. Although thermic manipulation thus did not provide better results as regards efficiency, this practice allowed to obtain stage 2 juveniles in different batches, spaced in time. Cangrejos de rio de la especie Austropotamobius pallipes se mantuvieron en laboratorio durante la fase reproductiva. De esta forma, apareamiento, puesta y todo el proceso de incubacion maternal de los huevos tuvieron lugar bajo condiciones controladas. Esto permitio la obtencion de datos biologicos reproductivos desde la puesta hasta el segundo estado juvenil. Durante el desarrollo embrionario, se ensayaron tres tratamientos termicos: temperatura constante de 11°C, temperatura ambiente y la inclusion de un periodo frio (3 semanas a 4°C). Las hembras presentaron una talla similar en los tres tratamientos (Longitud Media de Cefalotorax ± E.S.M. = 34,06 ± 0,11 mm). La produccion de juveniles estado 2 no mostro diferencias significativas entre regimenes termicos, aunque el numero medio mas alto obtenido por hembra (23) correspondio a animales mantenidos a temperatura constante. Igualmente, tampoco fueron detectadas diferencias significativas en los resultados de eficiencia reproductiva. El valor mas elevado (33%) fue obtenido con temperatura constante. Aunque la manipulacion termica no mejoro significativamente los resultados de eficiencia, esta practica permite la obtencion de juveniles estado 2 en diferentes lotes dentro de amplios margenes de tiempo., Adult freshwater crayfish, Austropotamobius pallipes, were maintained in the laboratory in such a way that mating, spawning, and maternal egg incubation took place under controlled conditions. This allowed to obtain data on reproductive biology from spawning to stage 2 juveniles. Three different thermal treatments were tested during embryonic development: a constant temperature of 11°C, ambient room temperature, and the incorporation of a cold period (3 weeks at 4°C). Females used in the three treatments tested were of a similar size (Mean Carapace Length ± Mean Standard Error = 34.06 ± 0.11 mm). Stage 2 juvenile production was not significantly different among the three regimes applied. The highest mean number of stage 2 juveniles per female (23) was obtained in animals maintained at constant temperature. Statistical differences were not detected, neither with regard to reproductive efficiency, in which the best value (33%) again was obtained at constant temperature. Although thermic manipulation thus did not provide better results as regards efficiency, this practice allowed to obtain stage 2 juveniles in different batches, spaced in time. Cangrejos de rio de la especie Austropotamobius pallipes se mantuvieron en laboratorio durante la fase reproductiva. De esta forma, apareamiento, puesta y todo el proceso de incubacion maternal de los huevos tuvieron lugar bajo condiciones controladas. Esto permitio la obtencion de datos biologicos reproductivos desde la puesta hasta el segundo estado juvenil. Durante el desarrollo embrionario, se ensayaron tres tratamientos termicos: temperatura constante de 11°C, temperatura ambiente y la inclusion de un periodo frio (3 semanas a 4°C). Las hembras presentaron una talla similar en los tres tratamientos (Longitud Media de Cefalotorax ± E.S.M. = 34,06 ± 0,11 mm). La produccion de juveniles estado 2 no mostro diferencias significativas entre regimenes termicos, aunque el numero medio mas alto obtenido por hembra (23) correspondio a animales mantenidos a temperatura constante. Igualmente, tampoco fueron detectadas diferencias significativas en los resultados de eficiencia reproductiva. El valor mas elevado (33%) fue obtenido con temperatura constante. Aunque la manipulacion termica no mejoro significativamente los resultados de eficiencia, esta practica permite la obtencion de juveniles estado 2 en diferentes lotes dentro de amplios margenes de tiempo.]

Duration of egg storage at different temperatures in the astacid crayfish Pacifastacus leniusculus: critical embryonic phase

Abstract The critical phase that would limit duration of egg storage in the astacid crayfish Pacifastacus leniusculus was investigated. Weekly monitoring was conducted during an 84-day period of storage at three different constant temperatures (15.5±1, 10.5±1.5 and 4±0.5 °C). After artificial incubation, stage 2 juveniles were only obtained from the lowest storage temperature, the sole treatment in which eggs did not reach the critical embryonic stage by the end of the storage. This limiting stage occurs at phase XII (embryo with pulsating heart) when embryogenesis of stored eggs ceased and phase XIII (eyed stage) was not reached. Eggs were also stored at a constant refrigeration temperature (4±0.5 °C) for periods ranging from 84 to 126 days. Mean survival rates to juvenile stage 2 were acceptable (approximately 50%) and different batches of juveniles were obtained over a 3-month period, depending on the duration of storage. The combined use of storage and artificial incubation techniques could have important applications to the development of astacid crayfish culture.

Successful storage and transport of eggs of the white-clawed crayfish (Austropotamobius pallipes Lereboullet)

Embryonated eggs of theEuropean native white-clawed crayfish Austropotamobius pallipes Lereboullet weresubjected to three periods of storage usingpolystyrene boxes and, afterwards, artificiallyincubated. At the end of the longest storage(42 days) survival rate was 98.3%, with 65%developed to stage 2 juvenile. Differentstorage periods allowed the staggeredproduction of juvenile batches within a monthperiod. The same containers used for storagewere also suitable for transport.

Effects of the presence or absence of males throughout spawning and maternal incubation on the reproductive efficiency of astacid crayfish (Austropotamobius pallipes) under controlled conditions.

Summary The separation of females and males after mating is a usual practice when the reproductive phase of astacids takes place under controlled conditions and is carried out to avoid egg losses due to male disturbance during spawning and embryonic development. In order to determine the possible effects of male presence on reproductive efficiency, two treatments were tested in the white-clawed crayfish (Austropotamobius pallipes): females alone, and females and males together throughout egg laying and embryonic development, respectively (mean female carapace length = 36.35 ± 0.57 mm). The mating period lasted 19 days. The overall rate of insemination was 98.3%. After 200 days of the experiment, a similar average number of stage-2 juveniles per female was obtained in the two treatments: 48.9± 7.1 in females alone and 46.3± 5.9 with males. In view of the difficulties in separating males and females, and the apparent lack of effect on reproductive efficiency, continued use of the practice should be reconsidered.

Storage and Transport of Embryonated Eggs of the Signal Crayfish Pacifastacus leniusculus

Abstract We evaluated storage of embryonated eggs of the signal crayfish Pacifastacus leniusculus in polystyrene boxes for 1, 3, 6, 28, and 56 d at two temperatures, 12 ± 1°C and 4 ± 0.5°C. For periods up to 4 weeks, survival at the end of storage for both temperatures exceeded 95%, and survival to stage-2 juvenile (after first molt) exceeded 63%. Following 8 weeks of storage, survival to stage-1 and stage-2 juveniles was significantly reduced. These experiments have shown the feasibility of egg storage for up to 4 weeks. In addition, 6-h transport (300 km) of embryonated eggs followed by up to 2 d of storage did not have a negative effect on egg viability.

Effects of breeder reuse on the reproductive potential of the signal crayfish ( Pacifastacus leniusculus Dana. Astacidae) in culture

The aim of this work was to evaluate the reproductive potential of the signal crayfish (Pacifastacus leniusculus Dana) in the second cycle under culture conditions. The experiment was carried out using 5,653 animals placed in six earthen ponds in August. Three treatments were performed, each in two ponds: breeder reuse (males and females used in the former reproductive cycle), female reuse (new males from the wild and females used in the former reproductive cycle) and new breeders (males and females from the wild). In April, close to hatching, egg-bearing females were transferred to the hatchery. Mortality of the reused breeders (around 30% of females and 41.4% of males) was significantly higher than that of the new breeders (11.4% of females and around 19.5% of males). The proportion of berried females close to hatching was significantly higher for the new ones (77.4% of the initial number), and the percentage of new females with a large quantity of eggs (63.6%) was higher than that of the reused females (25.6 and 20.9%). Differences among the percentages of females without eggs in the new breeders (11.2%) and the rest of the treatments (30.7 and 39.6%) were significant. The reproductive capacity of reused females was not improved by providing new males. Considering the number of females initially stocked into ponds, mean yield per new female was greater than that of the reused females, mainly due to the higher mortality recorded in the reused broodstock. Although the yield that can be obtained using the same breeders in two reproductive cycles drops in the second one, the production was not negligible.