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41.
Application of Bacillus thuringiensis tenebrionis (Bt) and expression of the Bt protein Cry3Aa in genetically modified crops are used for targeted control of the Colorado potato beetle Leptinotarsa decemlineata (Say). The Cry3A proteins are selectively toxic for the beetles but the present study describes effects of Cry3Aa on the Egyptian armyworm, Spodoptera littoralis (Boisduval). Cry3Aa expressed in potatoes or added to an agar-base wheat-germ diet reduced the growth of S. littoralis caterpillars and the fertility of adults. The effect of 1.4 mg kg(-1) Cry3Aa in potato leaves was comparable with that of 3.3 mg kg(-1) in the diet. This difference in activity was correlated with better digestibility and higher conversion efficiency of the diet that also supported higher reproduction rate: S. littoralis grown on the potatoes reached a similar size to those on the diet but laid only 702 instead of 1077 eggs per female. Cry3Aa consumption reduced body growth as a consequence of lower food intake without significantly affecting food digestibility and the conversion efficiency of nutrients. The 11% and 5% body weight reductions caused by 1.4 mg kg(-1) Cry3Aa in potatoes and 3.3 mg kg(-1) in the diet, respectively, were associated with 74% and 65% reduction in the number of progeny; S littoralis grown on a diet with 9.1 mg kg(-1) Cry3Aa were 10% smaller and produced no viable progeny. These data suggest that the curtailment of reproduction was not caused by a general shortage of nutrient reserves but by a more direct Cry3Aa effect on the reproduction process.  相似文献   
42.
43.
Examination of the original literature concerning species of Philometra (Philometridae, Dracunculoidea) parasitic in the abdominal cavity of European cyprinids revealed that P. abdominalis Nybelin, 1928 is a junior synonym of P. ovata (Zeder, 1803), a parasite of cyprinids of the genera Gobio, Phoxinus and Leuciscus. The valid name of the species parasitizing cyprinids of the genera Abramis, Rutilus and Vimba, mostly reported erroneously as P. ovata, is P. cyprinirutili (Creplin, 1825) comb. n.  相似文献   
44.
Andrya cuniculi (Blanchard, 1891) (Cestoda: Anoplocephalidae) is redescribed from Oryctolagus cuniculus (L.) from Spain. Large ranges of variability in body length and width, testes number and position of the cirrus sac were observed. An external seminal vesicle covered with small glandular cells is present. The pattern of development of the uterus is similar to that of Andrya rhopalocephala (Riehm, 1881). The only reliable differential characters to distinguish A. cunliculi from A. rhopalocephala are the position of the uterus in gravid segments and the position of the testes in mature segments. The uterus of A. cuniculi occupies the median field and parts of the lateral fields but is restricted to the median field in A. rhopalocephala. Testes are distributed more symmetrically lateral to the female organs in A. cuniculi but are mostly antiporal in A. rhopalocephala.  相似文献   
45.
Genetic variability and relationships among five cattle breeds (Holstein, Pinzgau, Limousin, Slovak Spotted and Charolais) bred in the Slovak Republic were investigated separately using 11 microsatellite markers and 61 blood group systems. Allele frequency, heterozygosity (Ho, HE) and PIC values were investigated. F-statistics were computed separately. For microsatellite markers FIS, FIT, FST and for blood groups HS, HT, GST parameters were calculated. Microsatellite and blood group comparison showed similar results by F-statistics but some differences were marked using the other methods. Both methods were able to detect close relation between Slovak Pinzgau and Slovak Spotted cattle breeds. Their relation was confirmed by genetic distance, principal component analysis (PCA) and coefficient of admixture (mY). Important divergences between different markers used in the study were observed by the characterisation of Limousin and Charolais breeds.  相似文献   
46.
Reexamination of the male holotype of the rhabdochonid nematode Rhabdochona leucaspii Kritscher, 1979, originally described from the intestine of the cyprinid fish Leucaspius prosperi [= Ladigesocypris ghigii (Gianferrari)] from Rhodes Island, Greece, confirmed its morphological and biometrical identity with Rhabdochona denudata (Dujardin, 1845), a common and widespread parasite of cyprinids and some other fishes in palaearctic Eurasia. Consequently, R. leucaspii is considered a junior synonym of R. denudata.  相似文献   
47.
Abstract: Over a 7-year period, parasites have been collected from 28 species of groupers (Serranidae, Epinephelinae) in the waters off New Caledonia. Host-parasite and parasite-host lists are provided, with a total of 337 host-parasite combinations, including 146 parasite identifications at the species level. Results are included for isopods (5 species), copepods (19), monogeneans (56), digeneans (28), cestodes (12), and nematodes (12). When results are restricted to those 14 fish species for which more than five specimens were examined and to parasites identified at the species level, 109 host-parasite combinations were recorded, with 63 different species, of which monogeneans account for half (32 species), and an average of 4.5 parasite species per fish species. Digenean records were compared for 16 fish species shared with the study of Cribb et al. (2002); based on a total of 90 parasite records identified at the species level, New Caledonia has 17 new records and only seven species were already known from other locations. We hypothesize that the present results represent only a small part of the actual biodiversity, and we predict a biodiversity of 10 different parasite species and 30 host-parasite combinations per serranid. A comparison with a study on Heron Island (Queensland, Australia) by Lester and Sewell (1989) was attempted: of the four species of fish in common and in a total of 91 host-parasite combinations, only six parasites identified at the species level were shared. This suggests strongly that insufficient sampling impairs proper biogeographical or ecological comparisons. Probably only 3% of the parasite species of coral reef fish are already known in New Caledonia.  相似文献   
48.
The enzymic hydrolysate of gluten from spelt wheat (Triticum aestivum subsp. spelta), an ancient protein-rich wheat subspecies, was subjected to repeated chromatography runs on the small pore size exclusion chromatography matrix, Biogel P-2. Two small peptide fractions were purified by rechromatography. The amino acid analyses carried out upon total hydrolysis of these fractions have shown a very high proportion of glutamic acid/glutamine, leucine, and methionine. The biological activity of the peptide fractions was tested on a model hybridoma at a concentration range from 0.02 to 0.2%. The most striking effect of peptide fractions, apparent even at the lowest concentrations tested, was a significantly higher persistence of viable cells on day 6, i.e., at the decline phase of the cultures. Culture viability values in the presence of peptide fractions were 64-74%, in comparison with 56% in the control culture. The results of this work are consistent with the concept that peptide molecules may act as antiapoptotic agents, survival factors, rather than serving as metabolic substrates.  相似文献   
49.
This is the first study describing the relation between the phase of the oestrous cycle and the number of mast cells (MCs) in the canine ovaries and uterine horns. The total number of MCs was counted in cortex ovarii, medulla ovarii, endometrium and myometrium. The number of MCs was compared in all of these areas among the bitches in the early follicular phase, luteal phase and anoestrus. MCs were the most numerous in the early follicular phase and in the luteal phase; however, they were significantly less numerous during anoestrus. Based on the results, it was concluded that the number of MCs in ovaries and uterine horns fluctuates during the oestrous cycle. The results of this study may contribute to clarifying the role of MCs in the reproductive organs of bitches.  相似文献   
50.
Two new gonad-infecting species of Philometra Costa, 1845 (Philometridae), P. brevicollis sp. n. and P. mira sp. n., are described from the ovary of the brownstripe red snapper, Lutjanus vitta (Quoy et Gaimard) (Lutjanidae, Perciformes), from the South Pacific Ocean off the coast of New Caledonia. Based on light and scanning electron microscopy examination, these new nematodes are compared with all other gonad-infecting species of Philometra. The former species (males and mature and gravid females available) mainly differs from its congeners in the length of males (5.39-5.92 mm), equally long spicules (279-312 microm), and the gubernaculum (151-168 microm), in that the distal end of the gubernaculum bears dorsolateral transverse lamella-like structures, and in the structure of the male caudal end. The latter species (only males available) is characterized by the length of males (3.47-3.66 mm), equally long spicules (96-105 microm), and the gubernaculum (78-84 microm), the absence of a dorsal reflected barb or lamella-like structures on the distal end of gubernaculum, and by the structure of the male caudal end. Judging from the occurrence in the host, P. brevicollis is the main philometrid parasitizing the gonads of L. vitta, in which it can reproduce, whereas this fish probably serves as only the paradefinitive host for P. mira. Both P. brevicollis and P. mira are the first nominal species of Philometra described from fishes of the family Lutjanidae.  相似文献   
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