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1.
Abdullahi Iliyasu Zainal Abidin Mohamed Mohd Mansor Ismail Amin Mahir Abdullah Salleh Mohamed Kamarudin Hashim Mazuki 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):221-247
Most research works on the production frontier in aquaculture focus on efficiency measurement using either Stochastic Production Frontier (SPF) or Data Envelopment Analysis (DEA). The studies on productivity growth in aquaculture were limited, perhaps due to lack of time-series data. Nevertheless, total factor productivity analysis (TFP) in fish farms has started gaining popularity in recent years. In addition, the majority of the efficiency studies have centered on technical efficiency analysis but substantial increases in the output levels can be fully realized through improving overall economic efficiency. Therefore, this review suggests that future research should estimate all three efficiency indices (i.e., technical, allocative and economic efficiencies). 相似文献
2.
Yeast cell wall and live yeast products and their combination in broiler diets formulated with weekly ingredient variations 下载免费PDF全文
J. Fowler M. Hashim A. Haq C. A. Bailey 《Journal of animal physiology and animal nutrition》2015,99(5):932-937
A 6‐week broiler study was conducted to evaluate whether subjecting the intestinal microflora of broilers to the effect of weekly variations in feed ingredients could be ameliorated by the inclusion of yeast‐derived feed additives: a yeast cell wall extract (YCW), live yeast culture (LY) or their combination (YCW + LY). Recent changes in ingredient prices have motivated producers to formulate diets not necessarily based primarily on corn and soya bean meal. Intestinal microflora in birds can vary significantly based on the ingredient composition of their diet, and the make‐up of the flora can influence overall bird performance. Within the three nutrient phases of this study, birds were fed either a traditional corn–soya ingredient profile or a variable‐ingredient regimen, which had weekly changes in the ingredient composition. There were consistent ameliorative effects of the yeast treatments in both the corn–soya and the variable‐ingredient groups throughout all 6 weeks, with the YCW + LY combination showing a reduced effect when compared to either product fed alone. The effectiveness of YCW and LY on ameliorating the effects of weekly ingredient variations appeared most effective during the starter and grower phases, but was less significant during the sixth week. 相似文献
3.
Based on biochemical assays and electrophoretical methods, the inhibitory effects of three plant meals (soybean meal, wheat meal, winged bean meal) on digestive alkaline proteases of discus were investigated. Casein assays revealed that increasing levels of soybean meal caused a linear inhibitory effect on activity of protease. SDS-PAGE images revealed that trypsin and chymotrypsin were the inhibited enzymes. Soybean showed the lowest inhibition rate followed by wheat meal and raw winged bean. There was a quadratic relationship between wheat meal levels and its inhibition of protease acitivity. The highest inhibitory effect was obtained with the winged bean meal with inhibition of caseinolytic activities ranging from 3.6–98.6%. Results from this study showed the potential of both soybean meal and wheat meal as ingredients for practical diet for discus, while demonstrating the need for further improvement in processing method for winged bean meal. 相似文献
4.
T cell receptor peptide therapy triggers autoregulation of experimental encephalomyelitis 总被引:12,自引:0,他引:12
Encephalitogenic T cells specific for myelin basic protein share common V beta 8 peptide sequences in their T cell receptor (TCR) that can induce autoregulatory T cells and antibodies that prevent clinical signs of experimental autoimmune encephalomyelitis (EAE). It is not known, however, if TCR peptides can treat established disease. To test its therapeutic value, TCR-V beta 8-39-59 peptide was injected into rats with clinical signs of EAE. This treatment reduced disease severity and speeded recovery, apparently by boosting anti-V beta 8 T cells and antibodies raised naturally in response to encephalitogenic V beta 8+ T cells. These results demonstrate that synthetic TCR peptides can be used therapeutically, and implicate the TCR-V beta 8-39-59 sequence as a natural idiotope involved in EAE recovery. Similarly, human TCR peptides may be effective in enhancing natural regulation of autoreactive T cells that share common V genes. 相似文献
5.
Effects of thiopentone and propofol on lower oesophageal sphincter and barrier pressure in the dog 总被引:1,自引:0,他引:1
The effects of thiopentone and propofol on oesophageal pressures were examined in 39 bitches. The dogs were premedicated with either atropine (n = 13), acepromazine maleate (n = 13) or a combination of atropine and acepromazine. Anaesthesia was induced with either thiopentone (15 dogs) or propofol (24 dogs), both given intravenously. Immediately following the induction of anaesthesia, gastric pressure and lower oesophageal sphincter pressure (LOSP) were measured and oesophageal barrier pressure determined. There were no significant differences attributable to the premedication regimens used but both LOSP and barrier pressure were significantly lower in the dogs anaesthetised with propofol compared to the animals given thiopentone (LOSP 12-2 ± 4-2 cm H2O propofol group versus 26-8 ± 6-5 cm H2O thiopentone group). 相似文献
6.
Mohammed Abdullah Al-Dohail Roshada Hashim & Mohammed Aliyu-Paiko 《Aquaculture Research》2009,40(14):1642-1652
This experiment was carried out to evaluate the effects of the probiotic, Lactobacillus acidophilus , on the growth performance, haematology parameters and immunoglobulin concentration in African catfish Clarias gariepinus fingerling. Two experimental diets were formulated to contain 35 g kg−1 crude protein and 10 g kg−1 lipids accordingly and fed three times daily for 12 weeks to 25 C. gariepinus fingerlings per fibreglass tank in 12 replicates each. The control diet was prepared with no probiotic supplementation whereas the second diet was prepared supplemented with a probiotic, L. acidophilus , containing about 3.01 × 107 colonies/g of diet. The results show that growth performance [specific growth rate (SGR) and relative growth rate (RGR)], nutrient utilization [protein efficiency ratio (PER) and feed conversion ratio (FCR)] and survival were significantly ( P <0.05) higher in fish maintained on the probiotic-supplemented diet compared with those on the control diet. Haematology parameters (packed cell volume, haemoglobin, erythrocyte sedimentation rate, red blood cell and white blood cell, total serum protein, Ca2+ , Mg2+ , Cl− , glucose and cholesterol) and total immunoglobulin concentrations were also significantly better in fish fed the probiotic-supplemented diet than in the control. Although the water quality parameters monitored were better in the fish fed the probiotic-supplemented diet than in the control, the parameters were not significantly different ( P >0.05). From the results of this experiment, we conclude that L. acidophilus can be used as a probiotic agent in African catfish culture, to enhance fish health, survival and better feed efficiency and growth performance. 相似文献
7.
Sutriana Amalia Akter Mst. Nahid Hashim Roshada Nor Siti Azizah Mohd 《Aquaculture International》2021,29(6):2769-2791
Aquaculture International - Single or combined effect of yeast, galactooligosaccharide (GOS), mannanoligosaccharide (MOS), and β-glucan was evaluated on the growth performance, nutrient... 相似文献
8.
对马来西亚2年和4年生巨草竹属天然林分的形态与解剖特征进行了研究。形态特征随着竹秆的年龄和高度发生变化。4年生薄壁组织和纤维的细胞壁厚度比2年生竹薄壁组织和纤维的细胞壁厚。在两个年龄组中,底部和上部的维管束的频率比中部频率大,在秆壁中部,2年和4年竹秆的导管直径没有区别。竹子的解剖结构与含水率和基本密度密切相关。 相似文献
9.
The objective of this study is to investigate the effect of different time and rates of boron (B) foliar application on olive (Olea europaea L.) tree's tissue boron concentration, total phenol, chlorophyll, total soluble sugars, and endogenous hormones. A field experiment was conducted during two successive seasons 2010/2011 and 2011/2012 using 20 years old olive trees cv. Frantoio. The trees are grown in sandy soil planted at 5 × 5 m apart under drip irrigation system at the Nuclear Research Center Experimental Farm, Inshas, El-Qaliubiya Governorate, Egypt. Boron was applied foliarly as boric acid at the following rates (0.0, 100, 200, 300, 400, 500 mg L?1) at flower initiation and after 1 and 2 months from flower initiation. Results showed that boron was significantly effective in increasing leaf, bud, and fruit boron concentration. Total phenol concentration in leaves and buds were significantly highest in the control treatment, significantly decreased as the boron application rate increased. Total chlorophyll, chlorophyll a and b, and total soluble sugars significantly increased as the boron application rate increased and the highest increase was achieved at 200 mg L?1 boron concentration rate. Leaf and bud endogenous indole acetic acid (IAA) and abscisic acid (ABA) were highest in the control treatment; they decreased as the boron application rate increased. However, gibberellic acid (GA3) increased in response to boron treatments compared with the control. The maximum increase was observed at 200 mg L?1 boron rate. We concluded that boron is mobile in olive tree as reproductive organs accumulated more boron than vegetative organs. There is evidence that boron is involved in reduction of phenols, increase in fruit set, and in sugar transport. A balance in endogenous hormones (IAA, GA, ABA) concentrations in olive tree has induced the maximum fruit set and yield. 相似文献
10.
Discus (Symphysodon spp.), a valuable ornamental species (mean initial weight 4.40–4.65 g) were fed five isoenergetic (gross energy: 200–209 kJ g–1), semipurified diets (casein, gelatine and Danish fish meal as protein sources) twice a day to satiation for 12 weeks. Five levels of protein were evaluated (350, 400, 450, 500 and 550 g kg–1 diet) and each fed to four replicates. Growth rate increased significantly with protein level up to 500 g kg–1 diet and then decreased. Feed conversion rates (FCRs) ranged from 2.2 to 3.8, varying inversely with observed growth rate. A similar trend was also observed in the efficiency of protein utilization (PER). Analysis of dose (protein level)‐response (growth rate) with second order polynomial regression suggested a requirement of 449–501 g kg–1. 相似文献