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991.
A comparison of the effect of dietary fungal phytase and dicalcium phosphate supplementation on growth performances,feed and phosphorus utilization of tra catfish juveniles (Pangasianodon hypophthalmus Sauvage, 1878)
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Six isonitrogenous (320 g kg?1) and isolipidic (60 g kg?1) diets were formulated with graded levels (0, 5, 10 and 15 g kg?1) of dicalcium phosphate (DCP) and fungal phytase (750 and 1500 FTU kg?1 diet). Tra catfish (Pangasianodon hypophthalmus), 9.6 g, were fed the diets for 12 weeks. Each experimental diet was fed to eight replicates of fish to apparent satiation. At the end of the trial, fish fed the diets containing 15 g kg?1 DCP, 750 and 1500 FTU kg?1 phytase had higher growth performances, protein efficiency ratio and phosphorus retention than those fed the control diet, 5 g kg?1 DCP and 10 g kg?1 DCP diets (P < 0.05). Whole body ash and phosphorus concentration of fish fed the 10 g kg?1 DCP and 15 g kg?1 DCP diets were significantly higher than those of fish fed the control diet. Higher apparent digestibility coefficient of phosphorus was observed in fish fed the phytase supplemented diets. The present results indicate that supplementation of phytase at 750 FTU kg?1 and 1500 FTU kg?1 improves growth performances, feed and phosphorus utilization. The supplementation can completely replace dicalcium phosphate or other phosphorus sources in tra catfish feed and reduce the phosphorus discharge into environment. 相似文献
992.
Hai T. H. Nguyen Geoff Deverteuil Neil Wrigley Kanchana N. Ruwanpura 《Growth and change》2014,45(2):377-396
Academic interest on domestic regulatory (and re‐regulatory) impacts of retail foreign direct investment remains surprisingly under‐researched, despite high‐profile campaigns, particularly in Southeast Asia, to rein in the expansion of retail transnational corporations. This paper focuses on the trends of re‐regulation of foreign retailers, particularly in the food sector, in Vietnam before and after the accession to the World Trade Organization (WTO) in 2007. The findings reveal a complex layering of regulation, some of it a holdover from the pre‐2007 period and some of it occurring since WTO accession, in the form of the controversial Economic Needs Test. 相似文献
993.
Jasper E. Burke Thuy Hien T. Nguyen Tanya Davis Amie Koenig Selena L. Lane Jennifer Good Benjamin M. Brainard 《Journal of veterinary diagnostic investigation》2021,33(4):703
Many point-of-care (POC) analyzers are available for the measurement of electrolytes and acid-base status in animals. We assessed the precision of the i-STAT Alinity v, a recently introduced POC analyzer, and compared it to 2 commonly used and previously validated POC analyzers (i-STAT 1, Stat Profile pHOx Ultra). Precision was evaluated by performing multiple analyses of whole blood samples from healthy dogs, cats, and horses on multiple i-STAT Alinity v analyzers. For comparison between analyzers, whole blood samples from dogs and cats presented to the emergency room were run concurrently on all 3 POC instruments. Reported values were compared by species (dogs and cats only) using Pearson correlation, and all values from all species were analyzed together for the Bland–Altman analysis. Results suggested that the i-STAT Alinity v precision was very good, with median coefficients of variability <2.5% for all measured parameters (except the anion gap), with variable ranges of coefficients of variation. In addition, good-to-excellent correlation was observed between the i-STAT Alinity v and i-STAT 1, and between the i-STAT Alinity v and Stat Profile pHOx Ultra for all parameters in both cats and dogs, respectively. In this cohort, the i-STAT Alinity v had clinically acceptable bias compared to the currently marketed analyzers and can be used for monitoring measured analytes in cats and dogs, although serial measurements in a single animal should be performed on the same analyzer whenever possible. 相似文献
994.
Evaluation of the water-quality dynamics in a eutrophic agricultural pond by using a one-box ecosystem model considering several algal groups 总被引:1,自引:1,他引:0
The Okubo pond is an agricultural pond located in the Itoshima area of Fukuoka Prefecture, Japan. It was constructed for irrigating
a nearby cultivated area. A monitoring program from August 11 to November 26, 2008, suggested the risk of eutrophication in
the water body. The high total nitrogen concentration (1.34 mg/l), high total phosphorus concentration (0.06 mg/l) and extreme
oxygen depletion (2 mg/l on 5 November 2008) exceeded the Japanese standards for paddy irrigation water. Furthermore, luxuriant
algal blooming in October indicated a hypereutrophic status according to the OECD (1982) criteria. In this study, a one-box ecosystem model was developed to obtain an insight into the seasonal variations in the
algal concentrations and chemical components of the Okubo pond with the aims of protecting its aquatic ecosystem and maintaining
its water quality. The model was based on a completely mixed system and included 12 water-quality indices: green algae, blue-green
algae, diatoms and dinoflagellates, cryptophytes, zooplankton, particulate organic matter, dissolved organic matter, phosphate–phosphorus,
ammonia–nitrogen, nitrite–nitrogen, nitrate–nitrogen, and dissolved oxygen. The monitoring data were used to verify the model
simulation. Model evaluation suggested good agreement between the predicted and the observed data for the seasonal variations
in the algal, nutrient, and dissolved oxygen concentrations. To determine the sensitivity of the model parameters, a sensitivity
analysis was conducted leading to the conclusion that the optimal temperature, growth rate, and respiratory rate of the four
algal groups, especially the ideal temperature for blue-green and green algae are the most influential factors determining
the variability affecting the model inference. From the model simulation, the water temperature and nutrient concentration
were considered to be the key limiting factors controlling alternative algal blooms in this period. 相似文献
995.
Seven years of performance data from a free surface flow constructed wetland system receiving agricultural runoff were used
to determine treatment performance and to develop regression and wetland design models. Removal rates by the wetland were
21–43.6% for 5-day biochemical oxygen demand (BOD5), 49.0–58.1% for total phosphorous (TP), 24.1–46.0% for total nitrogen (TN), and 57.6–77.8% for total suspended solids (TSS).
First-order area-based rate constant (k
20) values for BOD5 were 15.48 m/year in the early stage of observation and decreased to 12.00 m/year for the stable period. Similar results
were found for TP, for which k
20 values were 18.72 m/year in the early stage and 14.92 m/year for the stable period. For TN, k
20 values in the early stage (21.32 m/year) were slightly lower than those for the stable period (38.02 m/year). Finally, TSS
had values of 132.4 and 172.6 m/year in the early and stable periods, respectively. The low k
20 for BOD5 was not important for nonpoint source pollution control in the constructed wetland because these kinds of wetlands mainly
focus on nitrogen and phosphorus retention. The wetland area and outlet concentration could be approximately predicted using
the first-order kinetic model, but the maturity and hydraulic loading rate should be considered for more accurate prediction. 相似文献
996.
997.
Jae-Ik Han Hyoung-Won Son Seung-Cheol Park Ki-Jeong Na 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(4):341-344
P-glycoprotein (P-gp) is encoded by the ABCB1 gene and acts as an efflux pump for xenobiotics. In the Border Collie, a nonsense mutation caused by a 4-base pair deletion in the ABCB1 gene is associated with a premature stop to P-gp synthesis. In this study, we examined the full-length coding sequence of the ABCB1 gene in an ivermectin-sensitive Border Collie that lacked the aforementioned deletion mutation. The sequence was compared to the corresponding sequences of a wild-type Beagle and seven ivermectin-tolerant family members of the Border Collie. When compared to the wild-type Beagle sequence, that of the ivermectin-sensitive Border Collie was found to have one insertion mutation and eight single nucleotide polymorphisms (SNPs) in the coding sequence of the ABCB1 gene. While the eight SNPs were also found in the family members'' sequences, the insertion mutation was found only in the ivermectin-sensitive dog. These results suggest the possibility that the SNPs are species-specific features of the ABCB1 gene in Border Collies, and that the insertion mutation may be related to ivermectin intolerance. 相似文献
998.
Teck C. LOH Nguyen T. THANH Hooi L. FOO Mohd HAIR‐BEJO Bin K. AZHAR 《Animal Science Journal》2010,81(2):205-214
The effects of feeding different dosages of metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456) on the performance of broiler chickens was studied. A total of 504 male Ross broilers were grouped into 7 treatments and offered different diets: (i) standard corn‐soybean based diet (negative control); (ii) standard corn‐soybean based diet +100 ppm neomycin and oxytetracycline (positive control); (iii) standard corn‐soybean based diet + 0.1% metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456); (iv) standard corn‐soybean based diet + 0.2% of Com3456; (v) standard corn‐soybean based diet + 0.3% of Com3456 (vi) standard corn‐soybean based diet + 0.4% of Com3456 and (vii) standard corn‐soybean based diet + 0.5% of Com3456. Supplementation of Com3456 with different dosages improved growth performance, reduced Enterobacteriaceae and increased lactic acid bacteria count, and increased villi height of small intestine and fecal volatile fatty acid concentration. Treatment with 0.4% and 0.2% Com3456 had the best results, especially in terms of growth performance, feed conversion ratio and villi height among other dosages. However, the dosage of 0.2% was recommended due to its lower concentration yielding a similar effect as 0.4% supplementation. These results indicate that 0.2% is an optimum level to be included in the diets of broiler in order to replace antibiotic growth promoters. 相似文献
999.
Tolina T. Son DVM Lisa Thompson DVM DACVECC Sergi Serrano LV DACVECC Ravi Seshadri DVM DACVECC DAVBP 《Journal of Veterinary Emergency and Critical Care》2010,20(4):426-435
Objective – To evaluate clinical characteristics and outcomes of cats undergoing surgical intervention in the course of treatment for severe acute pancreatitis. Design – Retrospective observational study from 2003 to 2007 with a median follow‐up period of 2.2 years (range 11 d–5.4 y) postoperatively. Setting – Private referral veterinary center. Animals – Eight cats. Interventions – None. Measurements and Main Results – Quantitative data included preoperative physical and clinicopathologic values. Qualitative parameters included preoperative ultrasonographic interpretation, perioperative and intraoperative feeding tube placement, presence of free abdominal fluid, intraoperative closed suction abdominal drain placement, postoperative complications, microbiological culture, and histopathology. Common presenting clinical signs included lethargy, anorexia, and vomiting. Leukocytosis and hyponatremia were present in 5 of 8 cats. Hypokalemia, increased total bilirubin, and hyperglycemia were present in 6 of 8 cats. Elevated alanine aminotransferase and aspartate transferase were present in all cats. Surgery for extrahepatic biliary obstruction was performed in 6 cats, pancreatic abscess in 3 cats, and pancreatic necrosis in 1 cat. Six of the 8 cats survived. Five of the 6 cats that underwent surgery for extrahepatic biliary obstruction and 1 cat that underwent pancreatic necrosectomy survived. All 5 of the cats with extrahepatic biliary obstruction secondary to pancreatitis survived. The 2 nonsurvivors included a cat with a pancreatic abscess and a cat with severe pancreatitis and extrahepatic biliary obstruction secondary to a mass at the gastroduodenal junction. Postoperative complications included progression of diabetes mellitus, septic peritonitis, local gastrostomy tube stoma inflammation, local gastrostomy tube stoma infection, and mild dermal suture reaction. Conclusion – Cats with severe acute pancreatitis and concomitant extrahepatic biliary obstruction, pancreatic necrosis, or pancreatic abscesses may benefit from surgical intervention. Cats with extrahepatic biliary obstruction secondary to severe acute pancreatitis may have a good prognosis. 相似文献
1000.
Sangkeun Son Sung-Kyun Ko Mina Jang Jong Won Kim Gil Soo Kim Jae Kyoung Lee Eun Soo Jeon Yushi Futamura In-Ja Ryoo Jung-Sook Lee Hyuncheol Oh Young-Soo Hong Bo Yeon Kim Shunji Takahashi Hiroyuki Osada Jae-Hyuk Jang Jong Seog Ahn 《Marine drugs》2016,14(4)
Salterns, one of the most extreme natural hypersaline environments, are a rich source of halophilic and halotolerant microorganisms, but they remain largely underexplored ecological niches in the discovery of bioactive secondary metabolites. In continued efforts to investigate the metabolic potential of microbial populations from chemically underexplored sites, three new lipopeptides named iturin F1, iturin F2 and iturin A9 (1–3), along with iturin A8 (4), were isolated from Bacillus sp. KCB14S006 derived from a saltern. The structures of the isolated compounds were established by 1D-, 2D-NMR and HR-ESIMS, and their absolute configurations were determined by applying advanced Marfey’s method and CD spectroscopy. All isolates exhibited significant antifungal activities against various pathogenic fungi and moderate cytotoxic activities toward HeLa and srcts-NRK cell lines. Moreover, in an in vitro enzymatic assay, compound 4 showed a significant inhibitory activity against indoleamine 2,3-dioxygenase. 相似文献