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Effect of whole-body vibration in the vertical axis on cortisol and adrenocorticotropic hormone levels in piglets 总被引：5，自引：0，他引：5
Vibration, being a consequence of motion during transport, may impair the welfare of pigs. Therefore, the primary objectives of this study were 1) to evaluate during transport simulation the use of ACTH and cortisol plasma levels, which are part of a basic adaptation mechanism of pigs and 2) to define comfort conditions for pigs related to the frequency and acceleration of vibration. Pigs with a body weight between 20 and 25 kg were vibrated in the vertical direction for 2 h at 2, 4, 8, and 18 Hz, in combination with root mean square acceleration magnitudes of 1 or 3 m/s2. Blood was sampled at regular intervals before, during, and after vibration as the pig's behaviors were recorded. Data on ACTH, cortisol, and behavior could be collected from 104 vibrated pigs and 21 controls. In addition, eight animals (3 controls, 5 vibrated) were treated with 0.1 mg of dexamethasone/kg BW, eight animals (3 controls, 8 vibrated) with 0.1 mg naloxone/kg BW, and six (2 controls, 4 vibrated) with a physiological salt solution. Blood samples were taken and products were administrated via an intravenous catheter. The pigs spent less time lying during both hours of vibration treatment than during control conditions. Compared with 2 and 4 Hz, time spent lying was 10 times shorter at 8 Hz and 18 times shorter at 18 Hz. At 1030, ACTH levels were significantly higher than basal levels in animals vibrated at 2 (P < 0.0001), 4 (P < 0.002), and 18 Hz (P < 0.0006). After 1 h, levels returned to basal values. Cortisol levels increased very rapidly after the beginning of vibration (P < 0.0001) and remained higher until 1 h after cessation of vibration (P < 0.003). An inferrence of the lines of equal responses for ACTH and cortisol indicated that, in the beginning of vibration exposure, pigs were extremely susceptible to vibrations at lower frequencies (2 and 4 Hz), whereas at the end of vibration exposure the responses were higher at 18 Hz. The application of dexamethasone and naloxone underpinned the emotional component of the response strategy of pigs to vibration. Hence, vibration during transport should be minimized in order to enhance the adaptive capacities of pigs. 相似文献
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Bert Lagrain Ine Rombouts Herbert Wieser Jan A. Delcour Peter Koehler 《Journal of Cereal Science》2012
The high molecular weight subunits of wheat glutenin (HMW-GS) are important for bread-making quality. Their composition is routinely identified by Tris-glycine SDS-PAGE after reduction of glutenin disulfide bonds. However, the relation between their molecular weight and, hence, their primary structure, and their mobility in Tris-glycine SDS-PAGE has proven to be ambiguous. We demonstrate a Bis-Tris SDS-PAGE procedure with a neutral, instead of alkaline, pH in the gel and running buffers. In this method commonly occurring HMW-GS from wheat migrated in the order 5 > 2 ≈ 3 > 1 > 6 ≈ 2* > 7 > 8 > 9 > 12 > 10, which is different from the order obtained in the Tris-glycine system. HMW-GS were identified by N-terminal sequencing after isolation with RP-HPLC. Protein sequences of HMW-GS were further confirmed by LC-MS/MS analyses of chymotryptic peptides after comparing the MS data to amino acid sequences in protein databases. The numbers of amino acids of HMW-GS reflected well the mobility order in Bis-Tris SDS-PAGE. The results indicate that Bis-Tris SDS-PAGE may not only be used to identify HMW-GS, but also to estimate the length of their polypeptide chain, as such avoiding previously observed anomalies in migration order. 相似文献
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Koen J.A. Jansens Bert LagrainIne Rombouts Kristof BrijsMario Smet Jan A. Delcour 《Journal of Cereal Science》2011,54(3):434-441
A plastic-like material can be obtained by thermomolding wheat gluten protein which consists of glutenin and gliadin. We studied the effect of molding temperature (130-170 °C), molding time (5-25 min) and initial wheat gluten moisture content (5.6-18.0%) on the gluten network. Almost no glutenins were extractable after thermomolding irrespective of the molding conditions. At the lowest molding temperature, the extractable gliadin content decreased with increasing molding times and moisture contents. This effect was more pronounced for the α- and γ-gliadins than for the ω-gliadins. Protein extractabilities under reducing conditions revealed that, at this molding temperature, the cross-linking was predominantly based on disulfide bonds. At higher molding temperatures, also non-disulfide bonds contributed to the gluten network. Decreasing cystine contents and increasing free sulfhydryl and dehydroalanine (DHA) contents with increasing molding temperatures and times revealed the occurrence of β-elimination reactions during thermomolding. Under the experimental conditions, the DHA derived cross-link lanthionine (LAN) was detected in all gluten samples thermomolded at 150 and 170 °C. LAN was also formed at 130 °C for gluten samples containing 18.0% moisture. Degradation was observed at 150 °C for samples thermomolded from gluten with 18.0% moisture content or thermomolded at 170 °C for all moisture contents. 相似文献
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Ine Rombouts Bert Lagrain Kristof Brijs Jan A. Delcour 《Journal of Cereal Science》2010,52(3):362-367
The aim of this study was to increase insight into gluten polymerisation. While previous research on this topic focused on disulfide (SS) bonds, the present paper focuses on cross-links based on dehydro-protein formation through β-elimination reactions. Gliadin, the monomeric fraction of gluten containing no free sulfhydryl (SH) groups, was heated for 120 min at pH 8.0 and 130 °C, and cross-link formation was evaluated by determining extractability in sodium dodecyl sulfate containing buffer, reaction products of β-elimination reactions, and cross-links involving the latter. Heating decreased gliadin extractability. Reduction of SS bonds increased extractability of heated gliadin, but did not restore it to that of non-heated gliadin, suggesting contribution of both SS and non-SS bonds to gliadin cross-linking. Decreased SS levels and the presence of dehydroalanine and SH groups in heated gliadin samples indicated cleavage of SS bonds by β-elimination reactions. Some of the formed free SH groups were then involved in oxidation and/or SH–SS interchange reactions leading to intermolecular SS bonds. In addition, amino acid analysis revealed formation of an irreversible non-SS cross-link between dehydroalanine and the free SH group of cysteine, namely lanthionine. In conclusion, non-SS bonds may well contribute to the gluten network under specified reaction conditions. 相似文献
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Rombouts I Lagrain B Brunnbauer M Koehler P Brijs K Delcour JA 《Journal of agricultural and food chemistry》2011,59(4):1236-1243
Results in this paper confirm heat-induced isopeptide bond formation in wheat gluten. Heating (24 h, 130 °C) of wheat gluten [moisture content 7.4%] decreased its extractability in sodium dodecyl sulfate containing buffer (pH 6.8), even after reduction of disulfide (SS) bonds. Thus, both SS bonds and non-SS bonds were responsible for the extractability loss. Cross-links of the lysinoalanine and lanthionine type were not present in the heated samples, but heat treatment reduced levels of available amino groups. Heating of purified and alkylated high molecular weight glutenin subunits (HMW-GS) under similar conditions also resulted in extractability loss, demonstrating that cross-linking did not solely depend on the availability of cysteine or cystine. These observations indicated that heat treatment had induced isopeptide bond formation, resulting in larger and unextractable molecules. Heating HMW-GS lysine- and glutamine-containing peptides induced the formation of isopeptide bonds, thereby supporting the above hypothesis. The level of isopeptide bond formation increased with heating time. 相似文献
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R Akter AW Stent FM Sansom JR Gilkerson C Burden JM Devlin AR Legione CM El-Hage 《Australian veterinary journal》2020,98(11):570-573
Chlamydia psittaci was detected by PCR in the lung and equine foetal membranes of two aborted equine foetuses and one weak foal from two different studs in Victoria, Australia. The abortions occurred in September 2019 in two mares sharing a paddock northeast of Melbourne. The weak foal was born in October 2019 in a similar geographical region and died soon after birth despite receiving veterinary care. The detection of C. psittaci DNA in the lung and equine foetal membranes of the aborted or weak foals and the absence of any other factors that are commonly associated with abortion or neonatal death suggest that this pathogen may be the cause of the reproductive loss. The detection of C. psittaci in these cases is consistent with the recent detection of C. psittaci in association with equine abortion in New South Wales. These cases in Victoria show that C. psittaci, and the zoonotic risk it poses, should be considered in association with equine reproductive loss in other areas of Australia. 相似文献
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The dry milling of maize and accelerated fermentation of dough for kenkey production were studied as part of a wider investigation into the possibility of industrial production of a dehydrated kenkey flour. Dough containing an enrichment of lactic acid bacteria was used successfully to achieve, within 24-h incubation at 30°C, the required level of acidification of dry-milled maeze flour to obtain kenkey dough. Cabinet and drum drying were used to prepare dehydrated kenkey flour and pre-gelatinised aflata, respectively. Drum-drying was an effective method for the preparation of pre-gelatinised aflata, but it resulted in a 34% reduction in the titratable acidity (TA) of the fermented dough. Cabinet drying, on the other hand, had a less drastic effect on the TA of fermented dough, suggesting the possible use of a mixture of drum-dried aflata and uncooked cabinet-dried flour for convenient preparation of kenkey at the household level. Dry-milled maize flours had pasting and set-back viscosities that were inferior to those of the traditionally prepared doughs, and consequently they were unsuitable for the production of pre-gelatinised aflatas. Pre-getalinised aflata from unfermented dry-milled flours resulted in a crumbly and friable kenkey product. It was concluded, therefore, that, although dry-milling of maize and accelerated fermentation of dough could drastically reduce kenkey production time, from about 6 days to within 24 h, omission of the soaking step practised traditionally results in a product with inferior textural quality. 相似文献