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Effects of L-carnitine administration via drinking water on growth performance, carcass traits, blood serum parameters and abdominal fatty acid composition of ducks was examined. One hundred day-old Turkish native duck chicks were divided into two groups, each with five replicates and given the same diets with 0 and 200 mg/l carnitine chlorhydrate via drinking water. The study lasted 8 weeks, with the first 4 weeks as a starter and the last 4 weeks as grower period. At the end of the study five ducks were randomly selected from each subgroup for slaughter. Growth performance parameters of ducks were not affected significantly by L-carnitine administration. Live weight, daily weight gain, cumulative feed consumption and average feed conversion efficiency were found to be 1490 and 1621 g, 26.0 and 28.1 g, 5386 and 5662 g, 3.75 and 3.54 kg/kg in the control and in the carnitine groups respectively. L-carnitine administration did not effect carcass traits and serum cholesterol, total lipid, triglyceride and glucose levels. Total saturated fatty acid content of abdominal fat significantly decreased, mono- and polyunsaturated fatty acid content were not affected by L-carnitine administration. In conclusion, L-carnitine administration by drinking water did not affect growth performance, carcass traits and blood parameters in ducks. 相似文献
663.
CHARLES‐ANTOINE DEDRYVER JEAN‐FRANÇOIS LE GALLIC FRÉDÉRIQUE MAHÉO NICOLAS PARISEY DENIS TAGU 《Ecological Entomology》2012,37(4):293-299
1. To explore the possible causes of apparent changes in reproductive mode from obligate to cyclical parthenogenesis over time in recombinant clones of the aphid Sitobion avenae Fabricius, all F1 progenies from various crosses were tested for several consecutive years for sexual morph production, after several weeks' exposure to a short photoperiod. 2. Variable proportions of the F1 progenies from selfing and outcrossing holocyclic clones did not produce mating females when induction was attempted in the year of hatching, but only after further induction, the following year or after. This ‘delayed setting of the photoperiodic response’ (DSPR) was much stronger in recombinants from crosses involving only clones from oceanic regions than in those involving one clone from a region with a continental climate. 3. F1 progenies resulting from crosses between one holocyclic and one intermediate clone did not show DSPR. It appeared again in the F2. 4. DSPR preferentially affected the latest hatched clones in a given progeny. 5. This phenomenon is neither an experimental artefact nor as a result of clone contamination. It appears to be because of a genetically controlled quantitative trait affecting the length of the ‘interval timer’, and may represent an adaptation of holocyclic aphid clones from oceanic regions to unpredictable winter climates. 相似文献
664.
RODRIGO B. GONÇALVES 《Systematic Entomology》2016,41(2):430-440
The Augochlorini Beebe is a New World tribe of bees comprising 663 described species. Relationships among the genera of this monophyletic tribe remain uncertain. Here I provide a comprehensive phylogeny using morphological and molecular information. In all, 54 Augochlorini species plus 16 outgroups and 3017 molecular and 105 morphological characters were analysed. Sequences for four genes were analysed using Bayesian inference, maximum likelihood and parsimony. Morphological characters were taken from a literature review and analysed alone and in combination with molecular data using parsimony. The monophyly of Augochlorini and most genera is confirmed, with divergence of the main lineages of the tribe around 55–20 Ma. Seven clades were supported by most analyses and are here treated as genus‐level groups, as follows (combined analysis topology): (Corynura group, (Chlerogella group, (Rhinocorynura group, (Augochloropsis, (Megaloptidia group, (Neocorynura group, (Augochlora group, Megalopta group))))))). According to this topology, dim‐light foraging and cleptoparasitism arose three times in the tribe. According to my hypothesis, the diversification of Augochlorini may have begun as a response to vicariant events, including the split of the Neotropical/Andean regions and marine transgressions in the Amazon region. 相似文献
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Hüseyin Çavdar Oktay Talaz Deniz Ekinci 《Bioorganic & medicinal chemistry letters》2012,22(24):7499-7503
Here we synthesized four novel indole conduritol derivatives 1–4 for the first time in the literature and probed their biological activities with the α and β-glucosidases. The compounds showed quite effective glucosidase inhibitory action. IC50 values of the compounds were compared with the known glucosidase inhibitor acarbose and it was determined that newly synthesized indole conduritols had more powerful effect against β-glucosidase in addition to exhibiting moderate influence against α-glucosidase. Our molecules thus constitute an important starting point for the design and exploitation of novel glucosidase inhibitors since glucosidase inhibitors have widespread applications in the treatment of diabetes, viral infections, lysosomal storage diseases and cancers. 相似文献
667.
Fernando GONÇALVES Erich FISCHER Luiz Felipe Alves da Cunha CARVALHO Cláudia Márcia Marily FERREIRA 《Mammal Review》2012,42(4):304-309
Polydactyly in bats has rarely been observed; a few cases are recorded for insectivorous molossid and vespertilionid species in North America. Here we report polydactyly in the foliage‐roosting phyllostomid Artibeus lituratus, in the southern Pantanal floodplain and adjacent uplands, Brazil. Bats were mist‐netted in six populations, and capture rate per population was estimated. Of 444 A. lituratus individuals sampled, one female and one male exhibited supernumerary toes. These cases occurred in the two densest populations, in sites where forests are distributed in small disconnected fragments. This situation could favour increased inbreeding in A. lituratus and, indirectly, the manifestation of polydactyly. 相似文献
668.
Ece Terzioğlu Kara Ferdi Rıdvan Kiral Arzu Öztürk Çolak Arzu Çelik 《Archives of insect biochemistry and physiology》2020,104(2):e21675
The Drosophila inner photoreceptors R7 and R8 are responsible for color vision and their differentiation starts at the third instar larval stage. Only a handful of genes with R7 or R8-cell-specific expression are known. We performed an enhancer-trap screen using a novel piggyBac transposable element, pBGay, carrying a Gal4 sequence under the control of the P promoter to identify novel genes expressed specifically in R7 or R8 cells. From this screen, three lines were analyzed in detail: piggyBacAC109 and piggyBacAC783 are expressed in R8 cells and piggyBacAC887 is expressed in R7 cells at the third instar larval stage and pupal stages. Molecular analysis showed that the piggyBac elements were inserted into the first intron of CG14160 and CG7985 genes and the second intron of unzipped. We show the expression pattern in the developing eye imaginal disc, pupal retina as well as the adult retina. The photoreceptor-specific expression of these genes is reported for the first time and we propose that these lines are useful tools for studying the development of the visual system. 相似文献
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