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91.
Changes in crude protein (CP), non protein nitrogen (NPN), total sulphur (TS) contents, carbon/nitrogen (C/N) and nitrogen/sulphur (N/S) ratios and albumin protein (AP) were studied in four sizes of peas at various stages of the commercial canning process. Of all the parameters considered, NPN, AP, and TS showed the most regular trend to decrease during the commercial canning process. In this paper the use of these three parameters is proposed to obtain a Heat Treatment Index (HTI) applicable to raw, blanched and canned peas, according to the equation: HTI=(NPN×AP)/TS.  相似文献   
92.
93.
Canine hepatozoonosis is a tick-borne disease caused by protozoans of the genus Hepatozoon. Several tick species have been implicated as potential vectors. Therefore, extensive studies are needed to determine the 'natural' endemic cycle of this parasite. This paper presents the first report of the presence of Hepatozoon canis oocysts in Rhipicephalus (Boophilus) microplus collected from an infected dog.  相似文献   
94.
The pulping wood quality of Acacia melanoxylon was evaluated in relation to the presence of heartwood. The sapwood and heartwood from 20 trees from four sites in Portugal were evaluated separately at 5% stem height level in terms of chemical composition and kraft pulping aptitude. Heartwood had more extractives than sapwood ranging from 7.4% to 9.5% and from 4.0% to 4.2%, respectively, and with a heartwood-to-sapwood ratio for extractives ranging from 1.9 to 2.3. The major component of heartwood extractives was made up of ethanol-soluble compounds (70% of total extractives). Lignin content was similar in sapwood and heartwood (21.5% and 20.7%, respectively) as well as the sugar composition. Site did not influence the chemical composition. Pulping heartwood differed from sapwood in chemical and optical terms: lower values of pulp yield (53% vs 56% respectively), higher kappa number (11 vs. 7), and lower brightness (28% vs 49%). Acacia melanoxylon wood showed an overall good pulping aptitude, but the presence of heartwood should be taken into account because it decreases the raw-material quality for pulping. Heartwood content should therefore be considered as a quality variable when using A. melanoxylon wood in pulp industries  相似文献   
95.
Recent research is underway to study cork oak (Quercus suber L.) wood potential for production of wood components. A total of 35 stems of young and mature cork oaks were sampled, live sawn into flitches, scanned using VTT’s WoodCIM®, and the measured data computed by VTT’s PuuPilot software, allowing stem 3D reconstruction. Sawing simulations were run for 0.5 m and 1 m logs and the whole stem. Sawn products were (1) planks, (2) parquet, (3) lamparquet, and (4) external component of multilayer planks. Cork oak stems showed a moderate to small taper (mean 24 mm/m). Curviness varied between straight to significantly crooked stems (mean value 40 mm) Batch yields for the tested products ranged 25–43% and 37–50% for 0.5 m logs of young and mature trees, respectively; for 1 m logs, batch yields ranged 19–41% and 25–54%. When using the whole stem, batch yields were lower, ranging 11–38% and 15–50%. Higher yields were obtained for all log lengths and samples for production of lamparquet, parquet, and multilayer component.  相似文献   
96.
We investigated the genotype diversity and dynamics of Campylobacter in a commercial broiler flock during rearing and slaughter. In total, 220 Campylobacter jejuni isolates collected on four sampling occasions during rearing and from routine sampling during slaughter were subtyped by SmaI macrorestriction and pulsed-field gel electrophoresis, PFGE. Eight different SmaI types were found. During rearing, a subsequent addition of genotypes occurred, with two SmaI types found at 2 weeks of age and six types on the day before slaughter. All types that were detected in more than one isolate were also found on all succeeding sampling occasions, including the slaughter sampling. Two new types were found in the slaughter samples. In two-thirds of the individual birds sampled the day before slaughter, more than one SmaI type were found, although there was a clear tendency for dominance of one type in individual birds. Our results show that multiple genotypes of C. jejuni may be present in a commercial broiler flock during rearing and even in gastrointestinal tracts of individual birds. Both recurring environmental exposure and genetic changes within the population may explain the genotype diversity. Although the distribution of genotypes varied between different sampling occasions, we found no indication that any subtype excluded another during the rearing of the broiler flock.  相似文献   
97.
Tomato chlorosis virus causes yellow leaf disorder epidemics in many countries worldwide. Plants of Physalis ixocarpa showing abnormal interveinal yellowing and plants of Physalis peruviana showing mild yellowing collected in the vicinity of tomato crops in Portugal were found naturally infected with ToCV. Physalis ixocarpa and P. peruviana were tested for susceptibility to ToCV by inoculation with Bemisia tabaci, Q biotype. Results confirmed that ToCV is readily transmissible to both species. The infection was expressed in P. ixocarpa by conspicuous interveinal yellow areas on leaves that developed into red or brown necrotic flecks, while P. peruviana test plants remained asymptomatic. Infected plants of both P. ixocarpa and P. peruviana served as ToCV sources for tomato infection via B. tabaci transmission. This is the first report of P. ixocarpa and P. peruviana as natural hosts of ToCV.  相似文献   
98.
This study describes the immunocytochemical localization of the Bacillus sphaericus 2362 binary toxin components, BinA and BinB, in Culex quinquefasciatus larvae that had been intoxicated with this entomopathogen. Ultrathin sections of C. quinquefasciatus larvae midgut embedded in the hydrophilic resin L.R. White were incubated with the antibodies anti-BinA or anti-BinB and then revealed with goat anti-rabbit IgG coupled to gold particles. Immunocytochemical detection demonstrated the presence of specific labeling in ultra-thin sections that had been incubated with the BinA antiserum. Gold particles were detected on the apical areas of cell membranes and inside the epithelial cell cytoplasm, particularly the mitochondria, of cells from the gastric caeca and posterior stomach in larvae exposed during 2 or 24 h to the entomopathogen. A similar labeling pattern was observed in ultrathin sections from both midgut regions when incubated with BinB antiserum.  相似文献   
99.

This study aimed to compare feed efficiency measures of Nellore beef cattle on different residual intake and gain (RIG) classes. We used data from 610 animals weighing on average 236.33 kg and average of 283 days of age from feedlot performance tests carried out between 2005 and 2012. Animals were grouped based on RIG into three different classes: high RIG (>?mean?+?0.5 standard deviation (SD), most efficient; n?=?193), medium RIG (mean?±?0.5 SD; n?=?235), and low RIG (<?mean – 0.5 SD, least efficient; n?=?182). Residual feed intake (RFI), residual gain (RG), feed conversion ratio (FCR), feed efficiency (FE), relative growth rate (RGR), and Kleiber ratio (KR) of animals in each RIG class were compared by Tukey test at 1% of probability. Phenotypic correlations between variables were evaluated as well. Animals on high RIG class showed lower dry matter intake (P?<?0.01) and higher average daily gain (P?<?0.01) than low RIG animals. Consequently, high RIG animals had lower FCR (P?<?0.01) and higher FE (P?<?0.01) than those animals in low RIG class. The most efficient animals based on RIG were also the most efficient animals based on RG and RFI. RIG was negatively correlated to dry matter intake (P?<?0.01) and FCR (P?<?0.01), and a positive correlation was found between RIG and FE (P?<?0.01). Therefore, RIG appears to be a good parameter to select animals with reduced dry matter intake and high productive performance.

  相似文献   
100.
The present study was undertaken to examine the effect of recombinant chicken leptin administered to fed ad libitum and feed-restricted immature chickens of a layer strain on ovarian development and the timing of sexual maturity. In the first experiment 11-week-old pullets (77 days of age) fed ad libitum were injected daily with leptin at four dose levels (4, 16, 64 and 256 microg/kg body weight) until sexual maturity (lay of the first egg). Leptin treatment at the highest dose significantly (P<0.05) advanced the onset of puberty (day 116.3+/-1.0) in comparison to controls (day 121.3+/-1.2). The rises of luteinizing hormone, estradiol and progesterone in blood plasma were also advanced by leptin treatment. In the second experiment, both full-fed and feed-restricted pullets (79 days of age) were injected daily with leptin (256 microg/kg body weight). In birds fed ad libitum, exogenous leptin again significantly (P<0.05) advanced first ovipostion (day 118.4+/-1.4 versus day 124.4+/-1.7), while abolishing the significant (P<0.05) delay caused by feed restriction (day 131.5+/-1.6) and restoring the normal onset of sexual maturity (day 125.7+/-1.6). Analysis of the ovaries in 106-day-old pullets revealed that leptin injections advanced follicular development, particularly in birds fed ad libitum, and significantly (P<0.01) reduced follicular apoptosis both in full-fed and feed-restricted birds. In conclusion, we have shown that in female chickens exogenous leptin advances the onset of puberty by attenuation of ovarian apoptosis and enhancement of folliculogenesis.  相似文献   
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