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21.
Two hundred eighty-eight crossbred feeder pigs were used in 2 trials to determine the effects of feed and/or water deprivation at an auction market, and the effects of restricting the intake of the receiving diet on their serum chemical profile. The study also was designed to assess the value of the serum chemical profile as a diagnostic data base for stress disorders in feeder pigs. Performance data indicated that feeder pigs provided water only at the auction facilities lost significantly more weight than did those provided feed and water. Feeder pigs deprived of both feed and water were not significantly different in body weight from either group. Several serum chemical values (creatinine, triglycerides, cholesterol, blood urea nitrogen, and lactate dehydrogenase) were significantly influenced by feed deprivation, but not by feed and water deprivation. However, only the serum creatinine values were significantly different after the 24-hour posttransport period. There were no significant differences in pig weight or serum chemical values 84 days after pigs had arrived at the finishing unit. The serum chemical profile, widely used in human medicine, appears not to provide a reliable marker for identification of short-term nutritional deprivation, nor for transport stress in feeder pigs.  相似文献   
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An experiment was conducted to determine the effects of 1) long-acting oxytetracycline injection at market arrival, 2) feed or water access at the auction market and 3) receiving diet management on commingled feeder pig performance. A total of 288 commingled feeder pigs transported over 1,000 km after market management treatments were used in two trials. Pigs given access to feed and water (FW) at the market weighed more (P less than .001) following marketing and transport than pigs given water only (W). Pigs given neither feed nor water (N) were intermediate in arrival weight (19.7, 18.7 and 18.9 kg). There was no effect (P greater than .1) of feed and water offering at the market on final weight (96.6, 95.9 and 96.6 kg), overall average daily gain (.70, .69 and .70 kg/d), overall gain/feed (.31, .31, .32) or percentage death loss (1.0, 2.1 and 4.2%). Injection of long-acting oxytetracycline upon arrival at auction market had no effect (P greater than .1) on pig weight following marketing and transport (19.0 vs 19.2 kg), final weight (96.1 vs 97.0 kg), percentage death loss (3.4 vs 1.4%) or percentage of pigs treated (3.4 vs 4.9%). Compared to providing ad libitum access to feed, restricting feed intake by floor feeding for the first 7 d post-arrival reduced (P less than .01) rate of gain for the first 9 d (-.04 vs. .08 kg/d), but overall there was no effect (P greater than .1) on daily gain (.70 vs .69 kg/d) or gain/feed (.31 vs .31).  相似文献   
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The potential use of non-arable land in the al-Wusta region of the Sultanate of Oman for the production of algae biomass was examined. Brackish cleaned production water from oil production supplemented with commercial fertilizer was used as growth medium. The indigenous isolate Cyanobacterium aponinum WP7(1) was grown in open ponds using batch or semi-continuous cultivation. Biomass production rates of 15–24 g/m2/day were achieved. The change of salinity due to evaporation, which was thought to be a major challenge, did not exceed 35 ppt. All cultures showed contaminations with weed algae. Contaminations with green algae or diatoms were detectable using fluorescence pattern excited by four different wavelengths using a pulse-amplitude-modulation chlorophyll fluorometer (PAM). It is possible to estimate the health level and the mayor groups of which a culture is composed using the PAM method. Therefore, the fluorescence of the photosynthetically inactive sample is compared with the fluorescence after all copies of photosystem II were closed by exposing the sample to a high-intensity light beam. A detection limit of one weed algae cell in a hundred cells was achieved.  相似文献   
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After flavonol glycosides, monomeric flavan-3-ols, and dimeric and trimeric proanthocyanidins were fractionated from an extract of sea buckthorn (Hippophae rhamnoides) pomace by Sephadex LH-20 gel chromatography, oligomeric proanthocyanidins were eluted. The oligomeric fraction accounted for 84% of the total proanthocyanidins and 75% of the total antioxidant activity of the sea buckthorn pomace extract. To elucidate the structure of the oligomeric fraction, it was depolymerized by acid catalysis in the presence of phloroglucinol. The structure of the resulting flavan-3-ol monomers and flavan-3-ol-phloroglucinol adducts was determined by electrospray ionization mass spectrometry (ESI-MS) and (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy. Quantitative high-performance liquid chromatography investigations demonstrated (+)-gallocatechin as the predominating subunit in the oligomeric fraction. This observation was confirmed by ESI-MS, matrix-assisted laser desorption/ionization mass spectrometry, and (13)C NMR spectroscopy. The results showed that the majority of the flavan-3-ol subunits possessed a 2,3-trans configuration. The oligomers consisted mainly of prodelphinidin subunits whereas procyanidins were present in smaller amounts, indicating a very uncommon composition of the sea buckthorn proanthocyanidins. The mean degree of polymerization of the oligomeric proanthocyanidins was between 6 and 9.  相似文献   
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Abundant skeletal remains demonstrate that lambeosaurine hadrosaurid, tyrannosaurid, and troodontid dinosaurs lived on the Alaskan North Slope during late Campanian-early Maestrichtian time (about 66 to 76 million years ago) in a deltaic environment dominated by herbaceous vegetation. The high ground terrestrial plant community was a mild- to cold-temperate forest composed of coniferous and broad leaf trees. The high paleolatitude (about 70 degrees to 85 degrees North) implies extreme seasonal variation in solar insolation, temperature, and herbivore food supply. Great distances of migration to contemporaneous evergreen floras and the presence of both juvenile and adult hadrosaurs suggest that they remained at high latitudes year-round. This challenges the hypothesis that short-term periods of darkness and temperature decrease resulting from a bolide impact caused dinosaurian extinction.  相似文献   
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Fragmentary mandibles of Purgatorius unio Van Valen and Sloan from the Puercan (approximately early Paleocene), Garbani Locality, Montana, preserve associated postcanines. Their morphology indicates that this mammal was an early paromomyid primate and suggests that primate ancestry does not include currently known members of the palaeoryctid and leptictid Insectivora or of the Condylarthra.  相似文献   
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Cachexia is a multifactorial wasting syndrome most common in patients with cancer that is characterized by the uncontrolled loss of adipose and muscle mass. We show that the inhibition of lipolysis through genetic ablation of adipose triglyceride lipase (Atgl) or hormone-sensitive lipase (Hsl) ameliorates certain features of cancer-associated cachexia (CAC). In wild-type C57BL/6 mice, the injection of Lewis lung carcinoma or B16 melanoma cells causes tumor growth, loss of white adipose tissue (WAT), and a marked reduction of gastrocnemius muscle. In contrast, Atgl-deficient mice with tumors resisted increased WAT lipolysis, myocyte apoptosis, and proteasomal muscle degradation and maintained normal adipose and gastrocnemius muscle mass. Hsl-deficient mice with tumors were also protected although to a lesser degree. Thus, functional lipolysis is essential in the pathogenesis of CAC. Pharmacological inhibition of metabolic lipases may help prevent cachexia.  相似文献   
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