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31.
The diagnostic value of the cement gland and other abdominal structures in aleyrodid taxonomy 总被引:1,自引:0,他引:1
J. M. GUIMARÃES 《EPPO Bulletin》1996,26(2):413-419
The morphological characters on which the taxonomy of the Aleyrodidae is based are found in the last instar larvae (pupae). Since in many situations only adults are available (as in sticky trap catches), difficulties may arise if specific determination is needed. In fact, the information given by the vasiform structure of adults and the male genitalia is not always conclusive. In the course of the present study, two sources of useful information were found in the female abdomen, namely the morphology of the cement gland and the setal pattern of the gonapophyses. Both structures can easily be examined by light microscopy, with a simple method of preparation. These characters (mainly those concerning the cement gland) have been consistent enough to allow identification of the main whitefly pest species in Portugal. An identification key mostly based on these structures is presented for Aleurothrixus floccosus, Aleyrodes proletella, Bemisia tabaci, Parabemisia myricae, Siphoninus phillyreae, Trialeurodes vaporariorum and Dialeurodes citri (this last not yet found in Portugal). 相似文献
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M.V. DO CARMO E SÁ L.E. PEZZATO M.M. BARROS & P. DE MAGALHÃES PADILHA 《Aquaculture Nutrition》2005,11(4):273-281
A 90‐day feeding experiment was conducted with sex reversed Nile tilapia (Oreochromis niloticus) fingerlings fed purified or practical diets supplemented with different zinc sources to evaluate fish growth performance and zinc and iron retention in fish bones, fillets, liver, skin and eyes. The relative bioavailability value (RBV) of zinc in the supplemental sources tested was also calculated. Fish were fed with isonitrogenous and isoenergetic purified or practical diets supplemented with 150 mg Zn kg?1, as zinc sulphate monohydrate (ZnSO4), zinc oxide (ZnO) or zinc amino acid complex (Zn‐AA). The feeding trial was conducted in 30, 50 L aquaria where four 0.66 ± 0.01 g (mean ± SD) fingerlings were initially stocked. No significant differences were observed for any growth performance variables (P > 0.05). In practical diets, only ZnSO4 and ZnO presented bone zinc retention similar to that for the standard zinc source. Zinc concentration in the bone of fish fed practical diet supplemented with Zn‐AA (171 ± 3.62 μg g?1) was significantly lower than that verified for the practical diets supplemented with the standard zinc source (200 ± 17.7 μg g?1) or with ZnSO4 (204 ± 19.9 μg g?1). Assuming the concentration of zinc in bones as the response criterion, the supplemental zinc RBV from ZnSO4 (105%) was higher than the RBV for Zn‐AA (95.1%) or ZnO (94.9%). Iron concentration in the bones of animals fed the non‐zinc‐supplemented purified diet was significantly higher than that observed for purified diet supplemented with Zn‐AA (P < 0,05). The results of the present work allowed us to conclude that ZnSO4 in relation to ZnO or Zn‐AA was the supplemental zinc source with higher zinc bioavailability to Nile tilapia. 相似文献
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Apparent amino acid availability coefficients and protein digestibility of four animal products [fish meal (FM), meat and bone meal (MBM), poultry by‐product and feather meal] and four plant protein‐rich products [soybean meal (SBM), cottonseed meal‐28, cottonseed meal‐38 and corn gluten meal (CGM)] were determined for Nile tilapia, Oreochromis niloticus. Ingredients were incorporated to a practical reference diet at a 7 : 3 ratio (70% of reference diet and 30% of test ingredient). Chromic oxide was used as external digestibility marker. Among animal products poultry by‐product meal (PBM; 89.7%) and FM (88.6%) presented the highest apparent protein digestibility (APD) while MBM (78.4%) and feather meal (78.5%) presented the lowest APD. Among plant protein‐rich products CGM (91.4%) and SBM (92.4%) presented the highest APD values while cottonseed meal‐28 presented the lowest APD (78.6%). Average apparent amino acid availability of feed ingredients was similar to protein digestibility with 92.3%, 89.6%, 73.4%, 80.7%, 88.9%, 84.4%, 91.2% and 79.7% values for SBM, CGM, cottonseed meal‐28 and 38, FM, MBM, PBM and feather meal respectively. These results indicate that O. niloticus is able to utilize efficiently different feedstuffs. 相似文献
35.
Savani ES de Oliveira Camargo MC de Carvalho MR Zampieri RA dos Santos MG D'Auria SR Shaw JJ Floeter-Winter LM 《Veterinary parasitology》2004,120(3):229-233
A case of feline cutaneous leishmaniasis is reported in a domestic cat (Felis catus) as an apparently natural infection in a non-endemic area. Amastigotes were seem in smears of a nodular lesion on the cat's nose. No parasite could be seen in cytological preparations of liver or spleen but DNA obtained from a sample of the spleen produced the expected fragment in a Leishmania specific rDNA based PCR assay. The PCR product, a 520 bp fragment, was sequenced and the nucleotide sequence was identical to that of Leishmania (Leishmania) infantum chagasi. These results are surprising since no autochthonous human or canine cases of visceral leishmaniasis have ever been reported from this region. This case suggests that natural transmission of this disease is occurring in this area, and that cats could act as a reservoir of L. (L.) infantum chagasi. 相似文献
36.
NRO Paula G Galeati DIA Teixeira ES Lopes Júnior VJF Freitas D Rondina 《Reproduction in domestic animals》2005,40(2):108-110
For 6 months, 10 adult Saanen crossbred goats were fed undernutrition diet (70% maintenance), and finally five goats were refed for 6 weeks with 150% maintenance. In all animals oestrus was synchronized using 45 mg FGA vaginal sponge for 11 days, 300 IU eCG and 50 microg cloprostenol 48 h prior to sponge removal. From oestrus onset, during a 24-h period, blood samples were collected for oestradiol and NEFA assay. Ovulation was verified by laparoscopy 3 days after sponge removal. Body mass loss was 18.62 +/- 3.03% of initial weight and in refed goats body weight recovery was 90.63 +/- 3.56%. NEFA level was higher in restricted goats (p < 0.05). Fifty per cent of underfed goats (2/4) and all refed goats (4/4) exhibited oestrus and ovulation. Significant relationship (p < 0.05) was found between weight loss and the interval sponge removal-oestrus onset (r = 0.91) or ovulation rate (r = 0.70). Only in the refed group was the ovulation rate related to the oestradiol amount (r = 0.99) (p < 0.05). Collectively results showed that a short period of improved feeding re-established the responsiveness of oestrus synchronization in chronically fasted goats. 相似文献
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Mesoscale physical processes and the distribution and composition of ichthyoplankton on the southern Brazilian shelf break 总被引:1,自引:0,他引:1
BÁRBARA CRISTIE FRANCO JOSÉ HENRIQUE MUELBERT MAURICIO MAGALHÃES MATA 《Fisheries Oceanography》2006,15(1):37-43
The southern Brazilian shelf supports the largest fish stocks in the country, and studies on physical–biological processes in the ecology of ichthyoplankton have been recommended to provide a better understanding of the variability of the recruitment of fishing resources. This study is the first to examine the influence of mesoscale physical processes on the distribution of early life stages of fish in this shelf‐break region. Collections of fish eggs and larvae and measurements of temperature and salinity were made at 13 stations along cross‐shelf transects in December 1997. Myctophidae, Bregmacerotidae, Clupeidae, Synodontidae and Engraulidae were the most abundant larvae in the northern region, while Engraulidae and Bregmacerotidae prevailed further south. In situ hydrographic data, NOAA/AVHRR images and merged TOPEX/POSEIDON + ERS‐1/2 satellite altimetry taken during the cruise revealed an anticyclonic eddy dominating the shelf around 31°S. Larval fish abundance was lower at the centre of this feature, suggesting that the eddy advected poorer offshore waters of tropical origin towards the inner shelf‐concentrating the larvae around the eddy. 相似文献
39.
E Reddington A Sapienza B Gurau R Viswanathan S Sarangapani ES Smotkin TE Mallouk 《Science (New York, N.Y.)》1998,280(5370):1735-1737
Combinatorial screening of electrochemical catalysts by current-voltage methods can be unwieldy for large sample sizes. By converting the ions generated in an electrochemical half-cell reaction to a fluorescence signal, the most active compositions in a large electrode array have been identified. A fluorescent acid-base indicator was used to image high concentrations of hydrogen ions, which were generated in the electrooxidation of methanol. A 645-member electrode array containing five elements (platinum, ruthenium, osmium, iridium, and rhodium), 80 binary, 280 ternary, and 280 quaternary combinations was screened to identify the most active regions of phase space. Subsequent "zoom" screens pinpointed several very active compositions, some in ternary and quaternary regions that were bounded by rather inactive binaries. The best catalyst, platinum(44)/ruthenium(41)/osmium(10)/iridium(5) (numbers in parentheses are atomic percent), was significantly more active than platinum(50)/ruthenium(50) in a direct methanol fuel cell operating at 60 degreesC, even though the latter catalyst had about twice the surface area of the former. 相似文献