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51.
J. Iglesias J.J. Otero C. Moxica L. Fuentes F.J. Sánchez 《Aquaculture International》2004,12(4-5):481-487
This paper shows innovating results on Octopus vulgaris Cuvier 1797 growth under culture conditions during the whole life cycle. Experiments were conducted at the Spanish Institute of Oceanography of Vigo (Spain). Using mean water temperature of 22.5°C, salinity of 35‰ and adult Artemia (1–4 mm of total length) along with a diet complement of Maja squinado zoeae as living prey, it was possible to obtain a 31.5% paralarval survival at day 40 after hatching. At this age, paralarvae had reached a dry weight of 9.5 mg, 23 suckers per arm, and they began the settlement process. First results on juvenile growth showed that they reached 0.5–0.6 kg at the age of 6 months after hatching, and 2 months later, they attained weights ranging between 1.4 and 1.8 kg. Mean temperature of the ongrowing process was 18°C. 相似文献
52.
53.
José Iglesias María Jesús Lago Juan José Otero Castora Gómez Rosa Cal Francisco Javier Sánchez 《Aquaculture Research》2014,45(11):1754-1758
The effect of the adherence of the lipid droplet in the yolk‐sac on the growth and survival of the European hake (Merluccius merluccius) larvae was studied under starved and feeding conditions. Recently hatched hake larvae with adhered and non‐adhered lipid droplet (ALD and non‐ALD) were maintained during 8 days under starvation conditions. The adherence of the lipid droplet positively affected larval survival during starvation. At the end of the yolk consumption period (7–8 days after hatching), 90% of the surviving larvae had an ALD, while 10% of the survivors had a non‐ALD and showed a higher mortality rate. In a month feeding experiment, results show that the presence of non‐ALD in newly hatched hake larvae negatively affected their growth and survival. Dry weight and length (TL) of 20‐days‐old larvae with ALD were significantly higher than those with non‐ALD. Furthermore, lifespan of those larvae with non‐adhered lipid droplet was shorter, with most of them dying during the first 15–20 days of culture. As conclusion, the percentage of the lipid droplet adherence at hatching could be used as an indicator of ‘quality’ for European hake larvae: the greater the number of larvae with adhered lipid droplet, the better larval growth and survival. 相似文献
54.
55.
G Pazos J Fernández F Linares J Sánchez J J Otero J Iglesias P Domingues 《Aquaculture Research》2018,49(7):2440-2445
The present research describes the complete life cycle in captivity, including spawning, larval culture and fattening of juveniles until commercial size. Additionally, size, weight and age at each moulting stage were recorded, as well as zoeas biochemical composition. The most significant results obtained were as follows. Embryonic development lasted for 33 days. Each female had between three and five spawns, separated by 4–5 days each. Larval culture lasted for 20 days at 14–17°C. The zoeas turn to megalopa at ~11 days after hatch/DAH), and from megalopa to juvenile at ~20 DAH. Average survival was ~13%. Juvenile growth rate was higher during the first 8 months (0.22%–0.46% bw/day), and then gradually decreased when changing from live to frozen diets. Survival during the fattening phase was 63%. The final moult occurs at 450 DAH, when males and females have a carapace total length of 12.38 + 1.23 and 13.57 + 1.23 cm, respectively, and 541.56 + 104.26 and 670.68 + 162.6 g in total weight respectively. Biochemical composition of cultured zoeas showed a high amount of phospholipids and long‐chain fatty acids, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (ARA). Low survival rates in larval culture and especially after passing to the benthic life style are the main problems regarding spider crab culture, and need to be improved. 相似文献
56.
R. López D. Gondar A. Iglesias S. Fiol J. Antelo F. Arce 《European Journal of Soil Science》2008,59(5):892-899
We studied the acid‐base properties of 16 fulvic acids and 16 humic acids isolated from the surface (3–15 cm) and subsurface (> 45 cm) horizons of two types of acid forest soils, derived respectively from amphibolite and granite rocks, under five different types of vegetation. The observed differences between the contents of humic substances in the two types of soils were related to the degree of Al‐saturation of the soil organic matter, as indicated by the molar ratio between pyrophosphate extractable Al and C. Humic fractions were characterized in terms of elemental composition, and CPMAS 13C NMR spectrometry. The contents of carboxylic and phenolic groups were estimated by potentiometric titrations conducted in 0.1 m KNO3 in a nitrogen atmosphere. The fulvic acids contained more carboxylic groups but less phenolic groups than the humic acids: the ratio of phenolic to carboxylic groups in the humic acids was 0.48 ± 0.10 and in the fulvic acids 0.23 ± 0.05. The mean values of the protonation constants of each of the humic substance fractions can be used as generic parameters for describing the proton binding properties. The fulvic acids isolated from the subsurface horizon of the soil contained between 2.6 and 23% more carboxylic groups, and the humic acids between 8 and 43% more carboxylic groups than those isolated from the surface horizon of the same soil. 相似文献
57.
The species complex Arion hortensis s.l. is among the most important pestiferous slugs in Europe. The species A. distinctus Mabille and A. hortensis de Férussac have traditionally been grouped together under the denomination A. hortensis. Therefore, neither the feeding behaviour nor the susceptibility of the individual species to control measures are known. In the laboratory, mean daily consumption of lettuce was similar for both species. In a series of laboratory bioassays, A. distinctus and A. hortensis s.s. were exposed to the rhabditid nematode Phasmarhabditis hermaphrodita and to the chemical molluscicides metaldehyde and iron phosphate, and their feeding and health were measured. Both species showed a similar and low susceptibility to the biocontrol agent P. hermaphrodita. In field-collected slugs, the incidence of nematodes was much lower in A. hortensis s.l. than in Deroceras reticulatum or Arion lusitanicus. Metaldehyde and iron phosphate affected both slug species similarly. Therefore, our results do not indicate any major difference between the two slug species of agronomical relevance. 相似文献
58.
M L Sanmartín F Alvarez H Gijón Botella R Iglesias J Estévez R López-Román 《Folia parasitologica》1992,39(4):355-367
We have carried out a morphometric study of the ascaridoid nematode Toxocara genettae, parasite of the small intestine of the genet Genetta genetta, with the aid of scanning electron microscopy (SEM). Host specimens were trapped in Galicia, NW Spain. The most characteristic features of this nematode are the absence of cervical alae, replaced by narrow lateral crests running along the length of the body and the presence of a mucron at the end of the male tail. Other features of interest include the number of labial denticles (90-98 and 96-102 on the dorsal lip, 82-96 and 90-96 on the subventral lip of male and female, respectively), the width of the transverse striations (25-28 microns) and, in many of the specimens examined, the position of the precloacal median papilla at the base of a well-defined cuticular pit. 相似文献
59.
Lacau-Mengido IM Mejía ME Díaz-Torga GS Gonzalez Iglesias A Formía N Libertun C Becú-Villalobos D 《Journal of animal science》2000,78(4):817-824
Continuous treatment with ivermectin from birth to puberty advanced sexual maturation by 3.7 wk in Holstein heifers grazing pastures naturally infected with nematodes. Every 14 d jugular blood samples were taken from birth to 45 wk of age from all heifers. No differences in serum FSH, estradiol, or thyroxine levels were observed during the trial between the treated and untreated group. Mean LH levels were diminished in untreated heifers 4 wk before the first estrus and the amplitude of LH pulses was augmented in treated heifers when puberty was reached. Serum IGF-I levels increased from birth to 22 wk of age and then reached a plateau in both groups, but levels were consistently higher in treated heifers from 26 wk of age onward. Body weight gain was retarded in parasitized heifers and IGF-I values were positively correlated with body weight only during the first 20 wk of life. We suggest that enhanced prepubertal IGF-I levels in conjunction with increased prepubertal LH levels and pubertal LH pulse amplitude might be involved in the accelerated somatic maturation and in puberty advancement observed in ivermectin-treated heifers. 相似文献
60.