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21.
An experiment was conducted to determine chemical composition of raw and treated bitter vetch seed for use in poultry diets. Processing methods were: soaked in water for 12 h, then autoclaved and dried (SA); coarsely ground, soaked in water for 24 h, autoclaved and dried (GSA); coarsely ground, soaked in water for 47 h with exchange of water every 12 h, cooked and dried (GSC); coarsely ground, soaked in solution of 1% acetic acid for 24 h at 60°C and dried (GAA). Raw bitter vetch seed was contained 94.52, 26.56, 0.4, 58.86, 3.38, 5.32, 12.28 and 14.20 percent DM, CP, EE, NFE, Ash, CF, ADF and NDF, respectively. Its GE, AME, AMEn, TME and TMEn values were 18.10, 13.15, 14.38, 14.10 and 14.69 MJ/kg, respectively. Results indicated that bitter vetch is a good source of Fe (340 ppm) and Cu (46.7 ppm). It s amino acid profile was suitable and methionine was the first limiting amino acid when compared with broiler and layer chicks requirements. Its canavanine and tannin content were 0.78 and 6.7 mg/kgDM, respectively. Processing methods improved CP and in some cases AMEn. All processing methods especially GSC resulted in a significant (P < 0.05) reduction in canavanine and tannin.  相似文献   
22.
OBJECTIVE: To develop rapid (< 8 hour) tests using polymerase chain reaction (PCR) for the diagnosis of equine herpesvirus 3 (EHV3; equine coital exanthema virus), equine gammaherpesviruses 2 (EHV2) and EHV5, equine adenovirus 1 (EAdV1), EAdV2, equine arteritis virus (EAV), equine rhinitis A virus (ERAV; formerly equine rhinovirus 1) DESIGN: Either single round or second round (seminested) PCRs were developed and validated. METHODS: Oligonucleotide primers were designed that were specific for each virus, PCR conditions were defined and the specificity and sensitivity of the assays were determined. The application of the tests was validated using a number of independent virus isolates for most of the viruses studied. The PCRs were applied directly to clinical samples where samples were available. RESULTS: We developed a single round PCR for the diagnosis of EHV3, a seminested PCR for EHV2 and single round PCRs for EHV5, EAdV1, EAdV2 and RT-PCRs for EAV and ERAV. The PCR primer sets for each virus were designed and shown to be highly specific (did not amplify any recognised non-target template) and sensitive (detection of minimal amounts of virus) and, where multiple virus isolates were available all isolates were detected. CONCLUSION: The development and validation of a comprehensive panel of PCR diagnostic tests, predominantly for viruses causing equine respiratory disease, that can be completed within 8 hours from receipt of clinical samples, provides a major advance in the rapid diagnosis or exclusion diagnosis of these endemic equine virus diseases in Australia.  相似文献   
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The present experiment was conducted to determine the effect of muscle temperature during the prerigor and early postrigor period on meat tenderness, postmortem proteolysis, calpain system activity, water-holding capacity, and color. Lamb longissimus muscle (n = 14) from the right and left carcass sides was excised immediately after dressing, divided into an anterior and posterior sample, vacuum-packaged, and stored overnight at 5 to 35 degrees C. Further storage, up to 14 d postmortem, was at 2 degrees C. Tenderness at 1 d postmortem, tenderization during further storage, and postmortem proteolysis were negatively affected by overnight incubation above 25 degrees C. This effect could be explained by an effect of temperature on muscle contraction and activity of the calpain system. Muscle contraction was at a minimum after incubation at 15 degrees C. Water-holding capacity was negatively affected by incubation above 25 degrees C. Color scores improved with increasing incubation temperature at 1 d postmortem. However, after 14 d of postmortem storage, no differences in color scores were observed. Based on the present results and results of other groups, a temperature around 15 degrees C at the onset of rigor seems optimal to maximize tenderness without having detrimental effects on water-holding capacity or color.  相似文献   
25.
We investigated the effects of calpain-system genetic markers on consumer beef quality ratings, including interactions of marker effects with hormonal growth promotant (HGP) use and tenderstretch hanging. Brahman cattle in New South Wales (NSW; n = 164) and Western Australia (WA; n = 141) were selected at weaning from commercial and research herds to achieve balance and divergence in calpastatin (CAST) and calpain 3 (CAPN3) gene marker status. Genotypes for μ-calpain (CAPN1-4751 and CAPN1-316) were also determined. Angus cattle (49 in NSW, 17 in WA) with favorable CAST and CAPN3 alleles, balanced for CAPN1-316 status, were also studied. Half the cattle at each site had HGP (Revalor-H, containing 200 mg trenbolone acetate and 20 mg 17β-estradiol) implants during grain finishing. One side of each carcass was suspended from the Achilles tendon (AT) and the other from the pelvis [tenderstretch (TS)]. Meat Standards Australia consumer panels scored 7-d aged striploin steaks from both AT and TS sides, and 7-d aged rump and oyster blade steaks from the AT side of each carcass. Two favorable CAST alleles increased tenderness ratings of AT-striploin, TS-striploin, rump, and oyster blade steaks by, respectively, 6.1, 4.2, 4.2, and 3.1 units, and overall liking by 4.7, 2.8, 2.9, 3.7 (all P < 0.04). Two favorable CAPN1-4751 alleles increased tenderness of AT-striploin, TS-striploin, and rump steaks by 6.5, 4.3, and 3.9 units, and overall liking by 5.6, 3.1, and 4.1 units. Two favorable CAPN3 alleles improved rump steaks by 3.7, 3.3, 3.7, and 3.5 units, for tenderness, juiciness, liking the flavor, and overall liking. There were no significant CAPN1-316 effects. The effect of HGP was greatest for the AT-striploin (reducing tenderness and overall liking by 8.2 units, P < 0.001), then TS-striploin (-5.6 for tenderness, -5.0 for overall liking, P < 0.001), and then rump (-4.4 for tenderness, -3.3 for overall liking, P < 0.007). Processing conditions differed considerably between NSW and WA. Rump steaks from NSW scored about 10 units greater than those from WA, but Angus and Brahman steaks from the same location with the same marker alleles had similar scores. In contrast, NSW Angus striploin steaks scored about 15 units greater for tenderness and overall liking (P < 0.001) than cattle with the same marker alleles at the other 3 location × breed combinations, which had generally similar scores. Therefore, calpain-system gene markers have beneficial effects on eating quality, consistent with our previous findings for objective meat quality.  相似文献   
26.
上海嘉定区杨白潜蛾的生物学特性及防治   总被引:1,自引:0,他引:1  
2002~2004年对杨白潜蛾(LeucopterasusinellaHerrich-Schаffer)的生物学特性进行了研究,结果发现杨白潜蛾在上海1年发生5代,幼虫共5龄,1年有2个发生高峰期:6月中旬和9月中下旬;老熟幼虫作白色“H”形茧化蛹;以蛹在树干周围场所越冬;成虫产卵单列成行。药剂试验表明杀虫安、甲氨基阿维菌素、快绿扬、斑潜净对喷雾杨白潜蛾具有很高的防效,对杨树也有很好的保叶效果。  相似文献   
27.
Structural analysis from powder neutron and single-crystal x-ray diffraction data for a sample of the Tl2Mn2O7 pyrochlore, which exhibits colossal magnetoresistance (CMR), shows no deviations from ideal stoichiometry. This analysis gives an Mn-O distance of 1.90 angstroms, which is significantly shorter than the Mn-O distances (1.94 to 2.00 angstroms) observed in phases based on LaMnO3 perovskites that exhibit CMR. Both results in Tl2Mn2O7 indicate oxidation states very close to Tl23+Mn24+O7. Thus, Tl2Mn2O7 has neither mixed valence for a double-exchange magnetic interaction nor a Jahn-Teller cation such as Mn3+, both of which were thought to have an important function in CMR materials. An alternate mechanism for CMR in Tl2Mn2O7 based on magnetic ordering driven by superexchange and strong spin-fluctuation scattering above the Curie temperature is proposed here.  相似文献   
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29.
Relationships between temperament and a range of performance, carcass, and meat quality traits in young cattle were studied in 2 experiments conducted in New South Wales (NSW) and Western Australia (WA), Australia. In both experiments, growth rates of cattle were assessed during backgrounding on pasture and grain finishing in a feedlot. Carcass and objective meat quality characteristics were measured after slaughter. Feed intake and efficiency during grain finishing were also determined in NSW. Brahman (n = 82 steers and 82 heifers) and Angus (n = 25 steers and 24 heifers) cattle were used in the NSW experiment. In NSW, temperament was assessed by measuring flight speed [FS, m/s on exit from the chute (crush)] on 14 occasions, and by assessing agitation score during confinement in the crush (CS; 1 = calm to 5 = highly agitated) on 17 occasions over the course of the experiment. Brahman (n = 173) and Angus (n = 20) steers were used in the WA experiment. In WA, temperament was assessed by measuring FS on 2 occasions during backgrounding and on 2 occasions during grain feeding. At both sites, a hormonal growth promotant (Revalor-H, Virbac, Milperra, New South Wales, Australia) was applied to one-half of the cattle at feedlot entry, and the Brahman cattle were polymorphic for 2 calpain-system markers for beef tenderness. Temperament was not related (most P > 0.05) to tenderness gene marker status in Brahman cattle and was not (all P > 0.26) modified by the growth promotant treatment in either breed. The Brahman cattle had greater individual variation in, and greater correlations within and between, repeated assessments of FS and CS than did the Angus cattle. Correlations for repeated measures of FS were greater than for repeated assessments of CS, and the strength of correlations for both declined over time. Average FS or CS for each experiment and location (NSW or WA × backgrounding or finishing) were more highly correlated than individual measurements, indicating that the average values were a more reliable assessment of cattle temperament than any single measure. In Brahman cattle, increased average FS and CS were associated with significant (P < 0.05) reductions in backgrounding and feedlot growth rates, feed intake and time spent eating, carcass weight, and objective measures of meat quality. In Angus cattle, the associations between temperament and growth rates, feed intake, and carcass traits were weaker than in Brahmans, although the strength of relationships with meat quality were similar.  相似文献   
30.
In several mammalian species, the configuration of germinal vesicle (GV) chromatin correlates with the developmental competence of oocytes. Yet, no study has been published on the configuration of GV chromatin in ferret, nor is it known whether a specific configuration predicts meiotic competence in this species, in spite of the potential importance of ferret cloning to the study of human disease and to species conservation efforts. Here, we report on an analysis of the chromatin configuration in ferret GV oocytes and on how they correlate with meiotic development. Three distinct configurations were identified based on the degree of chromatin condensation: (1) fibrillar chromatin (FC), featuring strands of intertwined chromatin occupying most of the visible GV region; (2) intermediate condensed chromatin (ICC), characterized by dense, irregular chromatin masses throughout the GV; and (3) condensed chromatin (CC), which is highly compact and centered around the nucleolus. We also found that chromatin configuration was related to the extent of association with cumulus cells in cumulus–oocyte complexes; CC-configured oocytes were most often surrounded by a compact cumulus layer and also a compact corona but FC-configured oocytes were associated with neither. In addition, increasing chromatin condensation corresponded to an increase in oocyte diameter. Finally, following in vitro culture, significantly more CC-configured oocytes underwent maturation to meiotic metaphase II than did FC- or ICC-configured oocytes. We conclude that, in ferret, chromatin condensation is related to the sequential achievement of meiotic competencies during oocyte growth and differentiation, and thus can be used as a predictor of competence.  相似文献   
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