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1.
The use of molecular methods for rotavirus characterisation provides increased sensitivity for typing and allows the identification of putative reassortant strains. Reagents and methods for genotyping the virus need constant modification because of the reassortant nature of the virus. This study was aimed at designing and evaluating new oligonucleotide degenerate primer pairs that provide increased sensitivity and specificity for detecting avian rotavirus. Gene-specific primer pairs were designed by analysing different rotavirus strains isolated during the last decade by downloading them from the GenBank. The alignments were generated using clustal analysis from the BioEdit program. Degenerate nucleotides were included due to the reassortant nature of rotavirus. The consensus sequences were aligned using the BioEdit program and then treated with the Fast PCR software to derive the primers. The derived primer sequences were submitted for a BLAST search to ensure alignment was exclusive to the desired target genes. The designed primers had specific bands and were efficient in detecting rotavirus in faecal samples than previously published primers. Thus, a successful surveillance of rotaviruses requires that primer pairs be updated regularly in order to detect the emergence of novel or “unusual types”, which have occurred by genetic drift causing nucleotide changes at the primer binding sites that result in typing failures. We recommend the use of the proposed primers in molecular surveillance studies for efficient detection of avian rotavirus.  相似文献   
2.
Experiments were performed on 11 adult Red Sokoto goats (RSG) with the aim of determining their diurnal temperature fluctuations during the harmattan season. The rectal temperatures (RT) of goats were recorded with a standard clinical thermometer every hour from 06:00 to 19:00 hours. The RT of goats rose gradually from its minimum value of 38.3+/-0.1 degrees C at 06:00 hours and attained its peak value of 39.2+/-0.1 degrees C at 18:00 hours (P < 0.001). Thus, the RT values rose concurrently with increase in ambient temperature. The overall mean RT obtained was 38.7+/-0.1 degrees C. The diurnal fluctuation in the RT of the goats was 1.9+/-0.1 degrees C. There was a highly significant correlation between time of day and RT values (r = 0.947, P < 0.001). The results indicate a diurnal rhythm in the RT of the RSG, which agree with the established pattern of fluctuations in the RT of other breeds of goats. The high diurnal range of 1.9+/-0.1 degrees C confirms that the harmattan season is thermally stressful to the RSG.  相似文献   
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4.
This paper describes the physical features, climate, vegetation and animals of the Kwiambana Game Reserve as well as the history and the land use patterns around the Reserve. It also outlines the management problems and makes proposals to solve them. The management programme includes recommendations for game and habitat management, and general administration of the Reserve.  相似文献   
5.
Two forms of rhodanese were purified from the liver of Clarias gariepinus Burchell, designated catfish rhodanese I (cRHD I) and rhodanese II (cRHD II), by ion-exchange chromatography on a CM-Sepharose CL-6B column and gel filtration through a Sephadex G-75 column. The apparent molecular weight obtained for cRHD I and cRHD II was 34,500 ± 707 and 36,800 ± 283 Da, respectively. The subunit molecular weight determined by sodium dodecyl sulphate–polyacrylamide gel electrophoresis was 33,200 ± 283 and 35,100 ± 141 Da for cRHD I and cRHD II, respectively. Atomic absorption spectrophotometric analysis revealed that cRHD II contained a high level of iron (Fe), which presumably was responsible for the brownish colour of the preparation. In contrast, no Fe was identified in cRHD I, and its preparation was colourless. Further characterization of cRHD II gave true Michaelis–Menten constant (K m) values of 25.40 ± 1.70 and 18.60 ± 1.68 mM for KCN and Na2S2O3, respectively, an optimum pH of 6.5 and an optimum temperature of 40°C. The Arrhenius plot of the effects of temperature on the reaction rate consisted of two linear segments with a break occurring at 40°C. The apparent activation energy values from these slopes were 7.3 and 72.9 kcal/mol. Inhibition studies on the cRHD II enzyme showed that the activity of the enzyme was not affected by Mn2+, Co2+, Sn2+, Ni2+ and NH4 +, but Zn2+ inhibited the enzyme considerably.  相似文献   
6.
Vitamin E is an essential nontoxic fat‐soluble micronutrient whose effects on livestock performance and products can be attributed to its antioxidant and nonantioxidant properties. Although it is needed in small quantity in the diet, its roles in livestock production are indispensable as it is required in boosting performance, nutritional qualities, and yield of animal and animal products. The dietary or oral supplementation of vitamin E is essential in reducing lipid oxidation in muscle, egg, and dairy products as well as lowering cholesterol concentrations and improving antioxidant status of livestock. Evidence has shown that bioavailability of vitamin E–enriched animal products could serve as an invaluable nutritional benefit to consumers; especially those in regions of limited resources where vitamin E deficiencies pose a risk that may be detrimental to some cellular activities of the body and on human health. It is therefore important to redirect research on the impact of vitamin E supplementation as antioxidant on livestock performance and animal products.  相似文献   
7.
Glutathione transferase (GST) was purified from the hindgut of grasshopper (Zonocerus variegatus) a polyphagous insect. The purified enzyme had a native molecular weight of 40 kDa and a subunit molecular weight of 19 kDa. The purified enzyme could conjugate glutathione (GSH) with 1-chloro-2,4-dinitrobenzene (CDNB), paranitrobenzylchloride, paranitrophenylacetate, 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBDCl), and 1,2-dichloro-4-nitrobenzene (DCNB) with specific activities of 3.3 ± 0.3, 0.49 ± 0.10, 0.10 ± 0.002, 1.2 ± 0.2, and 1.7 ± 0.4 μmol/min/mg protein, respectively. CDNB appears to be the best substrate with a specificity constant, kcat/Km, of 1.8 ± 0.1 × 10−4 M−1 S−1. The kinetic mechanism of Z. variegatus GST (zvGST) in the conjugation of GSH with some electrophilic substrates appears complex. Conjugation of GSH with DCNB was inhibited by high DCNB concentration, while with NBDCl, as the electrophilic substrates, different values of Km were obtained at high and low concentrations of the substrates. Cibacron blue, hematin, S-hexylglutathione, and oxidized glutathione inhibited the enzyme with I50 values of 0.057 ± 0.004, 0.80 ± 0.2, 33 ± 2 μM, and 5.2 ± 0.3 mM, respectively. The nature of inhibition by each of these inhibitors is either competitive or non-competitive at varying GSH or CDNB as substrates. NADH and NAD+ inhibited the enzyme with an I50 value of 0.4 ± 0.01 and 11 ± 1 mM, respectively. NADH at a concentration of 0.54 mM completely abolished the activity. As part of its adaptation, the flexible kinetic pathway of detoxication by zvGST may assist the organism in coping with various xenobiotics encountered in its preferred food plants.  相似文献   
8.
Solanum nigrum was subjected to five fertilizer treatments on the field and glasshouse to determine the wild vegetable’s nutritional response to fertilizers with maturity and best fertilizer option for optimum harvesting period of the leaves for nutritional benefits. The application of 50 kg N/ha + 4.07 t manure/ha fertilizer increased protein uptake on the field and glasshouse, vitamin C in the glasshouse, and lipid on the field. The addition of 100 kg N/ha + 8.13 t manure/ha increased the uptake of vitamin C on the field and lipid content in the glasshouse. The control increased the accumulation of fiber on both the field and glasshouse while also lowering the phytate content in the glasshouse. Fiber was at peak 11 and 4 weeks after transplanting on the field and glasshouse, respectively, while lipids were highest 11 and 6 weeks after transplanting. Vitamin C was highest 9 and 6 weeks after transplanting on the field and glasshouse, respectively, after which it sharply declined toward senescence. Protein was at peak between the third and fourth weeks after transplanting. Although various nutrients responded differently to fertilizer treatments, these results indicate the potential of S. nigrum to meet the human nutritional recommended daily adequate intake values. Also, the results of this study indicate that the cultivation of this wild vegetable increases its nutritional composition as compared with the wild species. The best fertilizer option and best time to harvest the plant is best advised according to specific nutritional challenges. The consumption of S. nigrum could be expected to contribute a large proportion of the nutritional requirements in the human body.  相似文献   
9.
The effect of three smoking durations (60, 90, and 120 min) and two smoking temperatures (60°C and 70°C) on proximate composition and quality of brackish cultured milkfish steaks of 3 cm size was studied. No significant difference was observed in the sensory properties across all the samples, except in the overall acceptability of sample smoked at 60°C for 60 min. There was significant difference in the values obtained for the textures of all the samples. The L*a*b* values showed a significant difference in the raw and smoked samples. The moisture content showed significant difference in all six samples. Naphthalene, fluorine, and anthracene were detected in the raw sample and in all the smoked samples with significant difference, except for naphthalene. The effect of smoking on the sensory properties and the moisture content of a smoked fish sample are dependent on the smoking time and temperature. Polycyclic aromatic hydrocarbon (PAH) concentration in smoked fish can be a factor, based on both water pollution and the smoking procedure. Benzo-a-pyrene and PAH4, which are acceptable indicators of total PAH presence in smoked foods, were not detected in all the smoked samples, thereby indicating the products to be safe for consumption.  相似文献   
10.
Foliar micromorphology of Hippobromus pauciflorus (L.f.) Radlk (Sapindaceae) was investigated by scanning electron microscope examination. The leaves were characterized by anisocytic stomata which were found only on the abaxial surface. The leaves have long unicellular non-glandular trichomes which were distributed over the mid rib and densely populated at the edges of the upper and lower surfaces. Crystal deposits were also observed on the abaxial surface of the leaves. Energy dispersive X-ray spectroscopy SEM of the crystals showed predominant mineral components of Na, Al, Si, K and Ca ions. These micro (Si, Na and Al) and macro (K and Ca) elements are very essential to plant growth. Their presence in the trichomes could contribute to the mechanical stability of the leaf appendages.  相似文献   
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