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1.
The impact of feeding, fish size (body weight from 18.5 to 56.5 g) and water temperature (20 and 23 °C) on oxygen consumption (OC, mg O2 kg–1 h–1) and ammonia excretion (AE, mg TAN kg–1 h–1) was studied in Eurasian perch held in recirculation systems. OC for both fed and feed-deprived (3 days) fish was higher at 23 °C (278.5 and 150.1 mg O2 kg–1 h–1) than at 20 °C (249.3 and 135.0 mg O2 kg–1 h–1; P < 0.01). AEs for both fed and feed-deprived fish were also significantly higher at 23 °C than at 20 °C (P < 0.001). Water temperature and fish size had a significant impact on the oxygen:feed ratio (OFR, kg O2 kg–1 feed fed day–1) and ammonia:feed ratio (AFR, kg TAN kg–1 feed fed day–1; P < 0.001). Their average values at temperatures of 20 and 23 °C were 0.17 and 0.19 kg O2 kg–1 feed fed day–1 and 0.009 and 0.011 kg TAN kg–1 feed fed day–1, respectively. 相似文献
2.
The effect of supplemented commercial diets with crystalline l-tryptophan (TRP—5, 10 and 20 g TRP kg?1) on cannibalism, survival and growth parameters of pikeperch post-larvae (Sander lucioperca) was evaluated. Fifteen-day-old pikeperch larvae (mean weight—6.8 mg) were reared during the next 28 days (20.5 °C, 16L:8D) in glass aquaria in a recirculating aquaculture system. The enzyme-linked immunosorbent assay showed that TRP-supplemented diets were effective in increasing the levels of serotonin (5-HT) in the body tissue of pikeperch. TRP supplementation resulted in a slight decrease in both types of cannibalism, although the reduction in cannibalism impact did not amount to more than a few percent. TRP treatment had no significant influence on the final survival of pikeperch post-larvae (ranged from 20.1 ± 12.4 to 29.0 ± 12.9 %). However, contrary to the earlier studies conducted on other fish species, no significant difference in the growth rates and feeding behavior of pikeperch between TRP-fed and control group were found. The final body weight and growth rate ranged from 0.211 ± 0.014 to 0.243 ± 0.016 and from 12.19 ± 0.38 to 12.76 ± 0.35 % day?1, respectively. To our knowledge, this is the first study reporting the effects of TRP supplementation on the cannibalism–survival–growth relations in fish in the post-larval stage. 相似文献
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Monika Modzelewska-Kapituła Renata Pietrzak-Fiećko Zdzisław Zakęś Mirosław Szczepkowski 《Journal Of Aquatic Food Product Technology》2017,26(10):1312-1323
The aim of the study was to investigate the effects of northern pike origin (wild vs. farmed) and sex (female vs. male) on chemical composition, including fatty acids, and technological properties of fresh fillets. Fish origin influenced moisture, protein, fat, and ash contents, pH and color of the fillets, and the proportion of 22 out of 25 determined fatty acids, whereas sex affected expressible water, pH, lightness and redness of fillets, and only a single fatty acid (C20:0) proportion. Farmed pike had higher protein and fat content and lower moisture and ash than wild pike. Higher proportion and content of total polyunsaturated and n-3 fatty acids, as well as lower n-6/n-3 ratio, were found in farmed pike. Thus, it can be concluded that the commercial feed positively affected fatty acid proportion and content in the fish tissue and increased its nutritional value. 相似文献
5.
Andrzej K. Siwicki Zdzisław Zakęś John C. Fuller Jr Steven Nissen Krzysztof Kazuń Edward Głąbski 《Aquaculture International》2006,14(1-2):153-161
$\upbeta$ -Hydroxy- $\upbeta$ -methyl butyrate (HMB) has been shown to counteract many of the negative effects of intensive fish production methods and results in increased growth and protection against diseases. In the present study, the in vitro and in vivo effect of HMB on the immunocompetence cell activity in tench Tinca tinca (L.) was examined. In the in vitro study pronephric phagocytes and lymphocytes were isolated from the fish and grown in culture medium (RPMI-1640) containing 0, 0.1, 1, 5, 10, 25, 50 or $100\,\upmu$ g HMB cm?3 of medium. The effects of HMB on the respiratory burst activity (RBA), the potential killing activity (PKA) and lymphocyte proliferation stimulated by concanavalin A (ConA) or lipopolysaccharide (LPS) were examined. The in vitro study showed that HMB increased the RBA and PKA of the phagocytes, compared to the medium over that of cells grown without HMB. Lymphocyte proliferation stimulated by ConA and LPS was also increased approximately when HMB was added to the culture medium at concentrations between 10 and $100\,\upmu$ g HMB cm?3. In the in vivo study fish were fed daily with pellets containing HMB at doses 0, 10, 25 and 50 mg kg?1 body weight day?1. The study showed that HMB statistically increased the RBA and PKA and highest activity at 50 mg kg?1 body weight day?1 were observed. Also lymphocyte proliferation stimulated by ConA and LPS were maximally stimulated at dose 50 mg kg?1 body weight day?1. In conclusion, the current study shows that HMB could potentially improve immunocompetence cell activity in tench through increased cell proliferation and functionality. 相似文献
6.
Janina Przybylska Zdzisława Zimniak-Przybylska Paweł Krajewski 《Genetic Resources and Crop Evolution》1999,46(3):261-266
Electrophoretic analysis of seed albumins covered 66 Lathyrus accessions representing L. amphicarpos, L. blepharicarpus, L. cicera, L. gorgoni, L. marmoratus, L. pseudocicera and L. stenophyllus. The number of major albumin bands recorded in particular species varied from two in L. amphicarpos to eight in L. gorgoni. Apart from L. amphicarpos, all the species under study showed intraspecific variation. In total, 21 bands were distinguished. The results were compared with the corresponding data reported earlier for L. sativus. All the data were statistically analysed. The species examined in this study proved to be distantly related to L. sativus. Distinctness of particular Lathyrus species was quite marked except for L. cicera and L. marmoratus which produced similar electrophoretic seed albumin patterns. 相似文献
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Janina Przybylska Zdzisława Zimniak-Przybylska Paweł Krajewski 《Genetic Resources and Crop Evolution》1998,45(5):423-430
Electrophoretic analysis of seed albumins covered 105 Lathyrus sativus accessions originating from different geographical regions. Four major albumin bands were responsible for the detected variation. Due to differences in the number and combination of these bands, eleven electrophoretic seed albumin patterns were distinguished; four of them were rare phenotypes found in less than 1% of the 817 examined individuals. Electrophoretic data were subjected to statistical analysis using hierarchical UPGMA grouping and biplot techniques. Generally, no correlation was found between occurrence of either the seed albumin patterns or the major albumin bands and geographical origin of the forms under study. On the other hand, data concerning frequency distribution of the major albumin bands tended to separate two groups of accessions, white-seeded with large seeds and coloured-seeded with relatively small seeds; coloured-seeded accessions with rather large seeds mixed with the above groups. 相似文献
8.
ZdzisŁaw Zakęś Krystyna Demska-Zakęś PrzemysŁaw Jarocki Konrad Stawecki 《Aquaculture International》2006,14(1-2):127-140
The effect of feeding frequency (one, three, and continuous feeding), feed ration (0.2, 0.5, 0.8% of total fish biomass),
and feeding per se on the oxygen consumption (OC, mg O2 kg−1 h−1) and ammonia excretion (AE, mg TAN kg−1 h−1) of juvenile tench (body weight 15–19 g) and variations in these parameters in daily cycles were examined. Fish metabolism
was studied in a recirculating system (rearing tanks of 0.2 m3, water temperature 23 °C). It was found that oxygen consumption and ammonia excretion depended significantly on feed ration.
An increase of feed ration from 0.2 to 0.8% of fish biomass caused an increase of OC and AE from 126.80 mg O2 kg−1 h−1 and 1.95 mg TAN kg−1 h−1 to 187.35 mg O2 kg−1 h−1 and 8.80 mg TAN kg−1 h−1 (p<0.05). There was no dependence between feeding frequency and the mean rate of oxygen consumption. However, the relationship
between feeding frequency and ammonia excretion by juvenile tench was statistically significant (p<0.05). Feeding frequency significantly affected daily fluctuations of AE and OC. It was found that diurnal variations in
metabolic rates were strictly related to tench feeding, and the daily variations of AE were significantly higher than OC. 相似文献
9.
The effect of stocking density on the survival and growth of pikeperch, Sander lucioperca (L.), larvae was examined in two consecutive experiments. In experiment I, 4-day-old larvae [body wet weight (BW): 0.5 mg;
total body length (TL): 5.6 mm] were reared in 200-l cylindro-conical tanks in a closed, recirculating system (20 ± 0.5°C)
at three stocking densities (25, 50 and 100 larvae l−1) and fed a mixed feed (Artemia nauplii and Lansy A2 artificial feed) for 14 consecutive days. At densities of 25 and 100 larvae l−1, growth rate and survival ranged from 2.7 to 1.9 mg day−1 and from 79.2 to 72.3%, and fish biomass gain ranged from 0.6 to 2.0 g l−1, respectively. There were two periods of increased larval mortality: the first was at beginning of exogenous feeding and
the second during swim bladder inflation. In experiment II, 18-day-old larvae (BW: 35 mg; TL: 15.6 mm) obtained from experiment
I were reared under culture conditions similar to those of experiment I, but at lower stocking densities (6, 10 and 15 larvae
l−1). The fish were fed exclusively with artificial feed (trout starter) for 21 consecutive days. At densities of 6 and 15 larvae
l−1, the growth rate and fish biomass gain ranged from 28.8 to 23.1 mg day−1 and from 2.0 to 3.3 g l−1, respectively. The highest survival (56.5%) was achieved at a density of 6 larvae l−1. Mortality at all densities was mainly caused by cannibalism II type behaviour (27–35% of total). In both experiments, growth
and survival were negatively correlated and fish biomass gain positively correlated with stocking densities. The present study
suggests that the initial stocking density of pikeperch larvae reared in a recirculating system can be 100 individuals l−1 for the 4- to 18-day period post-hatch and 15 individuals l−1 for the post-19-day period. 相似文献
10.
Monika Fliszkiewicz Zdzis£aw Wilkaniec 《The Journal of Horticultural Science and Biotechnology》2013,88(5):457-460
SummaryMale wild bees visit flowers to feed and, despite their lack of specialised organs for carrying pollen, simultaneously pollinate them. We analysed the pollinating efficiency of the males of two bee species for blackcurrant (Ribes nigrum L.): red mason bee (Osmia rufa L.) and bufftailed bumblebee (Bombus terrestris terrestris L.). Both bee species are commercial pollinators and many males are produced during their rearing. Gauze sleeves were used to isolate the inflorescences and to keep the males inside (one per sleeve). In each experimental group, there were six shoots with four neighbouring inflorescences (n = 24). The sleeves were also used to prevent other bees from reaching the flowers, and to allow self-pollination. Non-isolated flowers were pollinated by free-range bees. The effect of male bee pollination was similar to that of free-range bee pollination. The percentages of flowers that developed into fruit were as follows: male bufftailed bumblebee pollination, 79.5%; free-range bee pollination, 71.1%; male red mason bee pollination, 65.1%; and self-pollination, 46.4%; while the mean numbers of fruit per raceme were 5.0, 4.4, 3.6, and 2.4, respectively. The number of non-pollinated flowers per raceme (ranging from 1.3 – 2.8) exhibited an inverse relationship to these numbers of fruit. Our observations showed that male wild bees can pollinate blackcurrant flowers successfully, and could potentially be useful in other crops. 相似文献