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In seminomadic farming practice, dry and lactating ewes are exposed to different degrees of water deprivation, leading to stress followed by various disease outbreaks. This study compares quantitatively the immunosuppression to Salmonella Enteritidis (SE) fimbriae (14 and 21 kDa) and other major polypeptides (28.9, 37.7, 42.9, 68.0, 92.6 and 96.8 kDa) in water-deprived dry and lactating ewes. Sixteen dry and lactating multiparous Awassi ewes were divided into four treatment groups (A, A', B and B'). Ewes in groups A and B were lactating, whereas ewes in groups A' and B' were dry. All ewes were administered a killed SE vaccine, subcutaneously in the neck, at the initiation of the experiment. The water availability for ewes in groups B (lactating) and B' (dry) was ad libitum, while that for ewes in groups A (lactating) and A' (dry) was once every 4 days. A serum sample was collected from the jugular vein of each ewe at zero time (initiation of the experiment, when SE bacterin was delivered) and at 2, 9, 12, 15 and 18 days post SE vaccination. The percentage reduction in the level of humoral antibody response to polypeptides of > or = 21 kDa was more apparent in water-deprived lactating ewes of group A between 9 and 18 days post initiation of thirst. In this period, immunosuppression to polypeptides > or = 21 kDa was present in 14 out of 16 observations in group A (water-deprived lactating), with significant immunosuppression in 9 observations in relation to the respective control (p<0.05), while it was present in only 4 out of 16 observations in group A' (water-deprived dry), with significant immunosuppression in 2 observations (p <0.05). In conclusion, immunosuppression to polypeptides of > or =21 kDa is more significant in lactating water-deprived ewes in the period 9-18 days post initiation of thirst, a result that will influence our future sheep welfare awareness programmes targeting an elimination of the practice of water deprivation in seminomadic sheep farming.  相似文献   
2.
Delignified cellulosic-supported biocatalyst, prepared by immobilization of kefir yeast on delignified cellulosic material (DCM), was found to be suitable for continuous, modified whey fermentation. The modified whey contained 1% raisin extract and molasses. Ethanol productivities ranged from 3.6 to 8.3 g L(-1)day(-1), whereas parameters such as ethanol concentration, residual sugars, and daily fermented whey productivity were acceptable for the production of potable alcohol and alcoholic drinks in industrial fermentations. The continuous fermentation bioreactor was operated for 39 days, stored for 18 days at 4 degrees C, and operated again for another 15 days without any diminution of the ethanol productivity. The concentrations of higher alcohols (propanol-1, isobutyl alcohol, and amyl alcohols) were low. The main volatile byproducts formed in the continuous process were similar to those observed in alcoholic beverages, and the fermented whey had a good aroma. The concentrations of higher alcohols were very low when compared to that of ethyl acetate, therefore resulting in a quality product. The possibility of using such a process for the production of potable alcohol or a novel, low-alcohol content drink is proposed.  相似文献   
3.
Forty-six surface sediment samples taken along the beds of boththe Jordan and Yarmouk Rivers were analysed for Pb, Cd, Zn, Fe andHg by atomic absorption spectrophotometer. Extraction techniqueswere used to establish the association of the total concentrations of Pb, Cd, Zn and Fe in the sediment samples withtheir contents in the exchangeable, carbonate, Fe/Mn oxides, organic and residual fractions.In the sediments of the Jordan River the recorded heavy metalsconcentrations were as follow: 8.1 ppm for Pb, 0.63 ppm for Cd, 20.3 ppm for Zn, 6 ppm for Hg and 1265.6 ppm for Fe; whereas in the sediment of Yarmouk River were 8.4 ppm for Pb, 0.67 ppm for Cd, 26.4 ppm for Zn, 6.2 ppm for Hg and 1370 ppmfor Fe. Pb, Cd, Zn, and Fe concentrations in the sediments ofboth rivers reflect the natural background value in shale, whereas Hg is moderately enriched. I-geo (geo-accumulation index) of metals in the sediments under study indicates thatthey are uncontaminated with Pb, Zn and Fe; contaminated tomoderately contaminated with Cd; and strongly contaminated with Hg. Heavy metal content in the sediments were found to be significantly influenced by different physico-chemical parameters. The effect of these physico-chemical parameters canbe arranged in the following order: clay fraction > organicmatter fractions > carbonate fraction > silt fraction. As sequential extraction procedure shows that the total concentration of the heavy metals are largely bound to the residual phase (retained 79.5% of Pb, 38% of Cd, 54.4% of Zn and 51.6% of Fe in Jordan River Sediments; and 88.6% of Pb, 48.2% of Cd, 37.6% of Zn and 59.5% of Fe in the YarmoukRiver sediments). The following sequence of mobility are suggested: Fe > Cd > Zn > Pb in Jordan River sediments, and Fe > Zn > Cd > Pb. in Yarmouk River sediments.  相似文献   
4.
A comparative study of the storage and reuse of immobilized yeast cells on apple pieces, kissiris, and gamma-alumina was carried out. The immobilized biocatalysts were allowed to remain in the fermented alcoholic liquid after the end of each fermentation batch for extended periods at 30 degrees C before reactivation in batch fermentation for wine-making. The results showed that the biocatalysts were able to reactivate and ferment after successively increased periods of storage compared to free cell systems both on glucose medium and on grape must. In glucose medium, apple-, kissiris-, and gamma-alumina-supported biocatalysts reactivated after 120, 80, and 83 days, respectively. Possible storage periods for grape must were lower but remained high. Immobilized yeast biocatalyst on apple pieces produced wines with an improved volatiles composition compared to kissiris- and gamma-alumina-supported biocatalysts. There were no significant negative effects on the fermentation activity and volatile byproduct composition.  相似文献   
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