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101.
A 6‐wk feeding trial was conducted to reevaluate the phosphorus (P) requirement of juvenile olive flounder and the bioavailability of various inorganic phosphorus sources (IPS). Eight experimental diets were prepared such that all diets contained the same amount of calories, nitrogen, and calcium. Each diet included 0.33% total phosphorus (TP) and 0.60 % total calcium supplied by the basal diet. The eight experimental diets were: the basal diet without P supplementation (BD), three diets consisting of the BD supplemented with NaH,PO4.2H2O (NaP0.45 NaP0.57 or NaP1.14) to supply 0.45, 0.57 or 1.14% TP, and four diets consisting of the BD supplemented with K2HPO4 (KP0.57), Ca(H2PO4);H2O (Cap0.57), CaH2PO4;2H2O (CaHP0.57) or flounder bone meal (FBP0.57) to supply 0.57% TP. Fish (N = 480)averaging 4.02 ± 0.03 g (Mean ± SD) were distributed randomly into 24 aquaria (20 fish per aquarium), and were fed one of the eight experimental diets in triplicate groups. The weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER) and feed efficiency (FE) of fish fed the NaP0.57 diet were significantly higher than those of fish fed the BD, NaP1.14, KP0.57, CaHP0.57 and FBP0.57 diets (P > 0.05). There was no significant difference in WG, SGR, PER, and FER among fish fed the Nap0.45, NaP0.57 and Cap0.57, diets. Whole body P retention (WBPret) in fish fed the Nap0.57 diet was significantly higher than in fish fed the BD, NaP1.14, KP0.57 CaHP0.57 and FBP0.57diets (P > 0.05). There was no significant difference in WBPret among fish fed the NaP0.47, NaP0.57, and CaP0.57, diets. The ability of the fish to digest the phosphorus in the NaP0.45, Nap0.57, NaP1.14, and CaP0.57 diets was significantly better than that of fish fed the other diets (P > 0.05). These results indicated that the dietary P requirement for juvenile olive flounder could be 0.45457%. Also, NaH,PO; 2H2O and Ca(H2PO4);H2O appeared to have a better bioavailability than the other P sources in juvenile olive flounder.  相似文献   
102.
Objective — To determine the minimum alveolar concentration (MAC) of desflurane (DES) in the horse.
Study Design — Prospective study.
Animals — Six healthy adult horses (three males and three females) weighing 370 ±16 kg and aged 9 ±2 years old.
Methods — Anesthesia was induced with DES vaporized in oxygen via a face mask connected to a large-animal, semiclosed anesthetic circle system. The horses were endotracheally intubated and positioned in right lateral recumbency. Inspired and end-tidal DES were monitored using a calibrated Ohmeda RGM 5250 multigas analyzer (Ohmeda-BOC, Spain). The MAC of desflurane that prevented gross purposeful movement in response to 60 seconds of noxious electrical stimulation of oral mucous membranes was determined.
Results — The time from the start of DES administration to lateral recumbency was 6.1 ±0.9 min. The MAC of DES in these horses was 7.6 ±0.4%. Time required for the animal to regain sternal recumbency after 98 ±4 minutes of anesthesia was 6.6 ±0.5 minutes and the time to standing was 14.3 ±2.7 minutes.
Conclusions — The MAC of desflurane in these horses was 7.6 ±0.4%. DES provided a rapid induction to, and recovery from, anesthesia.
Clinical Relevance — Desflurane offers the potential for more precise control during anesthesia, and may allow a faster and uneventful recovery. It is important to know the MAC of an inhalant to use it clinically.  相似文献   
103.
An 11-year-old, castrated male Miniature Poodle dog was referred due to daily plant eating followed by vomiting for 7 years. Each time the dog went out for a walk, he had been munched grass, and then vomited. There were no abnormal findings on medical examinations. Through behavior examination and consultation, we diagnosed this dog as having a plant eating problem. Because we assumed that the dog had eaten plants to supply of dietary deficiency or relieve digestive problems, advised the owner to discontinue supplying previous diet and to feed high-fiber diet. On the follow up, the owner said that the dog had not eaten plants and vomited from 3 days after initial dietary change. The dog has not shown any clinical signs for 13 months. This clinical finding shows a possibility that deficient diet, especially fiber, relates to the plant eating behavior of a dog.  相似文献   
104.
To determine the effectiveness of dietary lysine supplementation in cats with enzootic upper respiratory disease (URD), 50 cats were fed a ration containing 11 or 51 g lysine/kg diet for 52 days. Food intake, body weight, clinical signs, plasma amino acid concentrations and presence of Chlamydophila felis or feline herpesvirus (FHV)-1 DNA within the conjunctival fornix were assessed. Food and lysine intake of both dietary groups decreased between days 17 and 22, coinciding with peak disease and viral presence. Mean disease score for cats fed the supplemented ration (0.94) was higher than for those fed the basal diet (0.21); however, this could be attributed to a small subset of male cats which demonstrated fighting behavior that may have contributed to stress within that cage. FHV-1 DNA was detected on 12 occasions in six cats receiving the supplemented diet and on one occasion in one cat fed the basal diet. C felis DNA was never detected. Mean plasma arginine concentration was lower and plasma lysine concentration was higher in supplemented cats. Mean plasma arginine concentration declined throughout the study in both dietary groups. Data from the present study raise important questions but do not permit a definitive conclusion regarding the efficacy of dietary lysine supplementation in cats with enzootic URD.  相似文献   
105.
106.
Seasonal behaviour in sheep, which varies in tropical and temperate environmental conditions, is a matter of study, because it can provide a clue to address the problem of seasonality in sheep. Melatonin receptor is the membrane‐bound G‐coupled receptor, sensing the message of photoperiodic cues thorough melatonin. Restriction fragment length polymorphism (RFLP) studies were carried out to assess the variability of gene at G612A and C606T SNPs in MTNR1A gene, which have been studied to be markers for out‐of‐season breeding. Allelic frequency distribution corresponded to higher frequency of GG and CC genotype, in tropical arid sheep breed in comparison with temperate region sheep breed. PCR amplification of MTNR1A gene of 30 animals was performed and single nucleotide polymorphisms (SNPs) identification was carried out using Lasergene software. Seven SNPs/mutations were identified, but most of them were synonymous, except the one G706A, leading to substitution of valine by isoleucine. Polyphen‐2 analysis of G706A mutation revealed that it is a benign mutation. Two important SNPs C426T and G555A, which were identified in temperate sheep breeds, could not be traced in Magra and Marwari breeds of sheep. Thus, the Magra and Marwari breeds of tropical, arid region demonstrated the presence of both polymorphic SNPs markers G612A and C606T, associated with out‐of‐season breeding. GG and CC genotypes were having a higher prevalence in the studied population.  相似文献   
107.
Porcine circovirus type 2 (PCV2) is the primary causative agent for post-weaning, multisystemic, wasting syndrome. Consequently, serologic detection of and vaccination against PCV2 are important for the swine industry. Among several serological tests, the enzyme-linked immunosorbent assay (ELISA) is commonly used to measure anti-PCV2 antibody levels. In the present study, we used two commercial ELISA systems to comparatively evaluate anti-PCV2 antibodies in field pigs treated with three different PCV2 vaccines. Among a total of 517 serum samples, the results of the two ELISAs were fully concordant for 365 positive and 42 negative samples, indicating 78.7% agreement. In addition, the Pearson coefficient (0.636) indicated a moderate correlation between data from the two ELISAs. Results from the farms with pigs vaccinated with the three different PCV2 vaccines demonstrated that most of the vaccinated animals underwent seroconversion. However, the increase and duration of antibody titers varied depending on the vaccine, the presence of maternal antibodies, and the vaccination program. PCV2 serologic status and anti-PCV2 antibody levels of herds from this study could be utilized to determine the best timing for vaccination and assessing vaccination compliance.  相似文献   
108.

Purpose

Activated carbons (ACs) were applied to evaluate the effects of surface oxidation on bioavailability and bioaccumulation of cadmium (Cd) and copper (Cu) in freshwater sediment along with Eisenia fetida biomass change.

Materials and methods

A modified sequential extraction procedure was conducted to measure the changes in bioavailable fractions of heavy metals 6 weeks after the addition of nitric acid-oxidized AC. Bioaccumulation of heavy metals in E. fetida was analyzed after 2 weeks of exposure to AC-amended contaminated sediments. Changes in biomass of earthworms caused by AC amendments were observed over 2 weeks of exposure to clean sand.

Results and discussion

Surface oxidation of AC caused little impact on AC surface properties except for oxygen contents leading to enhanced sorption capacity for heavy metals. Bioavailable fractions of the heavy metals increased after 6 weeks, and less was bioavailable with various ACs than without AC. The earthworms were exposed to the sediments mixed with ACs for 6 weeks. After 2 weeks of exposure, bioaccumulation of Cd and Cu decreased drastically. More than 76 % of Cd and 80 % of Cu reductions were observed with each type and dose of AC. Weight loss of E. fetida incubated in clean sand for 13 days after AC amendments was observed, but was not affected by surface oxidation.

Conclusions

Inhibited growth of E. fetida due to AC could be responsible for the reduced bioaccumulation of Cd and Cu in the earthworms as AC inhibited the movement of earthworms, leading to less bioturbation and decreased consumption of nutrients.  相似文献   
109.
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter.  相似文献   
110.
Yoo CS  Nellis WJ 《Science (New York, N.Y.)》1991,254(5037):1489-1491
C(60) powders were shock-compressed quasi-isentropically and quenched from pressures in the range 10 to 110 GPa (0.1 to 1.1 Mbar). Recovered specimens were analyzed by Raman spectroscopy and optical microscopy. C(60) fullerenes are stable into the 13- to 17-GPa pressure range. The onset of a fast ( approximately 0.5 micros) reconstructive transformation to graphite occurs near 17 GPa. The graphite recovered from 27 GPa and about 600 degrees C is relatively well ordered with crystal planar domain size of about 100 A. Above 50 GPa a continuous transformation to an amorphous state is observed in recovered specimens. The fast transformation to graphite is proposed to occur by pi-electron rehybridization which initiates breakup of the ball structure and formation of the graphite structure at high density.  相似文献   
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