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41.
The total body composition of 4 x 10 female, 5-month-old New Zealand White rabbits was determined, using direct chemical analysis and computerised tomography (CT). Ten non-pregnant rabbits (control) and 3 x 10 pregnant rabbits at days 14, 21 and 28 of gestation, respectively, were included in the study. With the advancement of pregnancy, the body weight (BW) of does significantly (P < 0.05) increased (control: 3255 g, day 28: 3938 g), while the dry matter, DM (control: 43.02%, day 28: 40.94%), ether extract, EE (control: 20.15%, day 28: 18.13%), crude protein, CP (control: 20.15%, day 28: 18.13%), and energy concentration decreased (control: 12.41 MJ/kg BW, day 28: 11.81 MJ/kg BW). During pregnancy the protein content of uteri (control: 12.24%, day 28: 49.45% of DM) and the retained energy in the form of uterus with fetuses (day 14: 0.824 MJ, day 28: 2.189 MJ) increased, while the dry matter (control: 82.39%, day 28: 28.96%) and ether extract content (control: 86.05%, day 28: 45.92% of DM) of uteri decreased. With the advancement of pregnancy the dry matter (day 14: 39.70%, day 28: 18.65%) and crude protein (day 14: 75.74%; day 28: 63.63% of DM) content and the number of fetuses (day 14: 8.8; day 28: 6.4) decreased, while their fat concentration (day 14: 10.13%, day 28: 24.34% of DM) increased. According to the equations created from the CT pictures, body fat (R2 = 0.871) and energy (R2 = 0.926) content can be predicted with high accuracy. The accuracy of predicting body protein content is much lower (R2 = 0.356), which can be improved by introducing the body weight as a new dependent variable (R2 = 0.797). It can also be concluded that, in contrast to other animal species, rabbit fetuses show considerable development not only in the last trimester of gestation but already from the second half of pregnancy.  相似文献   
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Horseflies (Diptera: Tabanidae) can cause severe problems for humans and livestock because of the continuous annoyance performed and the diseases vectored by the haematophagous females. Therefore, effective horsefly traps are in large demand, especially for stock-breeders. To catch horseflies, several kinds of traps have been developed, many of them attracting these insects visually with the aid of a black ball. The recently discovered positive polarotaxis (attraction to horizontally polarized light) in several horsefly species can be used to design traps that capture female and male horseflies. The aim of this work is to present the concept of such a trap based on two novel principles: (1) the visual target of the trap is a horizontal solar panel (photovoltaics) attracting polarotactic horseflies by means of the highly and horizontally polarized light reflected from the photovoltaic surface. (2) The horseflies trying to touch or land on the photovoltaic trap surface are perished by the mechanical hit of a wire rotated quickly with an electromotor supplied by the photovoltaics-produced electricity. Thus, the photovoltaics is bifunctional: its horizontally polarized reflected light signal attracts water-seeking, polarotactic horseflies, and it produces the electricity necessary to rotate the wire. We describe here the concept and design of this new horsefly trap, the effectiveness of which was demonstrated in field experiments. The advantages and disadvantages of the trap are discussed. Using imaging polarimetry, we measured the reflection-polarization characteristics of the photovoltaic trap surface demonstrating the optical reason for the polarotactic attractiveness to horseflies.  相似文献   
44.
The genetic diversity present in the breeding programs of southeast Europe was assessed in a set of 114 winter wheat (Triticum aestivum L.) cultivars using AFLP and SSR markers. The average genetic diversity characterised with the Jaccard’s distance coefficient was 0.605 with an interval of 0.053 and 0.889. The wheat cultivars originating from the four countries differed from each other in their clustering patterns, including the numbers of clusters and the most prevalent cluster, which was breeding program-specific. Hungarian and Romanian cultivars showed closer relationships, and Serbian and Macedonian cultivars grouped together more frequently. The phenotypic variability of the same cultivars was assessed under diverse ecological conditions of the four growing sites, measuring the disease resistance against two foliar diseases, and several agronomic traits. Of the phenotypic traits, powdery mildew and leaf rust responses showed significant associations with genetic diversity, whereas heading date, plant height and yield components did not. Through parallel assessment of genotypic and phenotypic diversity it was possible to separate winter wheat cultivars with similar genotype but diverse phenotype from those with similar phenotype but diverse genotype. This information will allow breeders to make informed decisions in selecting parents for new crosses.  相似文献   
45.
Invasive Phytophthora species are responsible for severe tree diseases in many forest ecosystems in Europe. In Hungary, the symptoms were first noted when P. alni infection led to a serious decline and mortality of alder stands in the late 1990s. Between 2001 and 2009, over 300 soilborne Phytophthora isolates were collected from declining broadleaf forests in Hungary, and 10 Phytophthora species identified based on morphological traits and the molecular characteristics of the internally transcribed spacer (ITS) regions of the nuclear ribosomal DNA. The most diverse species spectrum, found in diseased alder stands, included P. gonapodyides, P. gregata, P. inundata, P. lacustris, P. megasperma, P. plurivora, one informally designated taxon: P. taxon hungarica, and one unnamed species P. sp.1. P. cactorum and P. plurivora isolates were prevalent in the soil of a declining eastern black walnut forest, and three species, P. gonapodyides, P. multivora and P. plurivora were recovered from a declining oak stand. More than one ITS-based genotype was identified for four species, including six genotypes for P. gonapodyides, and two each for P. cactorum, P. plurivora and P. inundata. The high genetic diversity of the P. gonapodyides isolates may indicate that the species is indigenous to the region. In contrast, the frequently recovered, widely distributed P. lacustris with a single ITS genotype may represent a recent colonizer. The P. multivora isolates are, to date, the first reported from a European native forest.  相似文献   
46.
Journal of Plant Diseases and Protection - Apricot aphid, Myzus mumecola (Matsumura) (Homoptera: Aphididae), was recorded as a new pest of apricot in Hungary in the spring of 2020. Identification...  相似文献   
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48.
Having repeatedly retrieved an object from a location, human infants tend to search the same place even when they observe the object being hidden at another location. This perseverative error is usually explained by infants' inability to inhibit a previously rewarded search response or to recall the new location. We show that the tendency to commit this error is substantially reduced (from 81 to 41%) when the object is hidden in front of 10-month-old infants without the experimenter using the communicative cues that normally accompany object hiding in this task. We suggest that this improvement is due to an interpretive bias that normally helps infants learn from demonstrations but misleads them in the context of a hiding game. Our finding provides an alternative theoretical perspective on the nature of infants' perseverative search errors.  相似文献   
49.
Molecular markers (PCR–RFLP and microsatellite) were used to investigate the genetic background of the only brown trout (Salmo trutta m fario) broodstock in Hungary which due to the hydrogeography of the country should theoretically belong to the Danubian lineage. PCR–RFLP (mitochondrial DNA control region and lactate dehydrogenase and somatolactin genes) as well as microsatellite (BFRO002, OMM1064, Ssa408uos, SsoSL417, SsoSL438) markers were used to distinguish between Danubian and Atlantic lineages of brown trout in the Lillafüred broodstock. Altogether 435 fish were tagged during the experimental period. Due to mortalities, fin clips were collected from 401 individuals. According to the genetic analysis of the mitochondrial DNA, the Danubian haplotype is present in only one individual (0.2 %) of the broodstock. Analysis of the nuclear markers revealed that alleles characteristic of both the Atlantic and the Danubian lineages are found in the population. However, Atlantic alleles dominate throughout the broodstock which is in Hardy–Weinberg equilibrium according to the investigated markers. Results indicate that the original broodstock that was introduced to the farm following its construction in 1933 was of the Atlantic lineage. Although later fish from a local stream were collected and added to the broodstock, the number of these was limited and they were almost exclusively males. Fish from this farm that are stocked by anglers can have a significant genetic impact on trout populations of natural streams.  相似文献   
50.
The transfer of L-ascorbic acid (AA) from broodstock to the fertilised eggs and it's dynamics in embryos and fasting larvae, has been studied in sea bass (Dicentrarchus labrax L.) and sea bream (Sparus aurata L.). Two types of diets were fed to the broodstocks: one containing sufficient ascorbate for normal growth and the other with an extra addition of a very high dose (2,000 mg/kg feed) of ethyl-cellulose-coated L-ascorbic acid.The concentration of AA and total ascorbate (L-ascorbic acid plus dehydroascorbic acid) was detected through several embryo and larval development stages, including larvae just before feeding. In sea bass and sea bream, the mean (SD) concentration of total ascorbate in fertilised eggs originating from broodstock fed AA supplemented diet, was 218.5 (17.7) and 122.4 (5.1) g/g wet weight respectively. This was significantly higher (P < 0.01) than the unsupplemented groups, which contained only 155.9 (6.9) and 103.9 (3.5) g/g wet weight respectively. A diet with a vitamin C content adequate for normal growth, may not be sufficient for broodstock when the goal is transfer of TAA to embryos. © Rapid Science Ltd. 1998  相似文献   
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