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61.
Forty‐eight castrated male goats were used to determine the effects of feeding green tea by‐products (GTB) on growth performance, meat quality, blood metabolites and immune cell proliferation. Experimental treatments consisted of basal diets supplemented with four levels of GTB (0%, 0.5%, 1.0% or 2.0%). Four replicate pens were assigned to each treatment with three goats per replicate. Increasing dietary GTB tended to linearly increase the overall average weight gain and feed intake (p = 0.09). Water holding capacity, pH and sensory attributes of meat were not affected by GTB supplementation, while cooking loss was reduced both linearly and quadratically (p < 0.01). The redness (linear; p = 0.02, quadratic; p < 0.01) and yellowness (quadratic; p < 0.01) values of goat meat were improved by GTB supplementation. Increasing dietary GTB quadratically increased protein and decreased crude fat (p < 0.05), while linearly decreased cholesterol (p = 0.03) content of goat meat. The proportions of monounsaturated fatty acid, polyunsaturated fatty acid (PUFA) and n‐6 PUFA increased linearly (p < 0.01) and n‐3 PUFA increased quadratically (p < 0.05) as GTB increased in diets. Increasing dietary GTB linearly increased the PUFA/SFA (saturated fatty acid) and tended to linearly and quadratically increase (p ≤ 0.10) the n‐6/n‐3 ratio. The thiobarbituric acid‐reactive substances values of meat were lower in the 2.0% GTB‐supplemented group in all storage periods (p < 0.05). Dietary GTB linearly decreased plasma glucose and cholesterol (p < 0.01) and quadratically decreased urea nitrogen concentrations (p = 0.001). The growth of spleen cells incubated in concanavalin A and lipopolysaccharides medium increased significantly (p < 0.05) in response to GTB supplementation. Our results suggest that GTB may positively affect the growth performance, meat quality, blood metabolites and immune cell proliferation when supplemented as a feed additive in goat diet.  相似文献   
62.

A total of 1000 clinically healthy small ruminants comprising 500 sheep and 500 goats from five districts within Riyadh Province in Saudi Arabia were investigated by routine Giemsa staining for hematozoan parasites. Out of these, 100 sheep and 95 goat samples were investigated by PCR using three pairs of hemoprotozoan-specific primers. Based on microscopic examination, 33.2% of sheep and 25.2% of goats were found infected with hemoprotozoan parasites, while PCR detected hematozoan infection in 46% of sheep and 33.7% of goats. Extensive molecular characterization of hematozoan infection using six pairs of species-specific primers revealed the dominance of Theileria ovis, rather than any other species, which is recorded for the first time in small ruminants in Saudi Arabia. Prevalence of T. ovis in sheep and goats was found to be the highest in Riyadh (32, 48%) followed by AL-Kharj (31, 35%), Ad-Dawadimi (31, 33%), AL-Majmaah (15, 27%), and Rumah (17, 23%). The highest parasite prevalence was recorded in the 3 years of age and >?4 years of age ruminants, while the lowest prevalence was recorded in <?1 year of age ruminants. No noticeable differences in parasite prevalence between male or female ruminants were recorded. Partial sequencing of 18S rRNA gene revealed the infection of the studied ruminants with four new isolates of T. ovis. Further characterization of the pathogenicity and the clinical effects of these T. ovis isolates in sheep and goats is highly needed. The current results can be helpful in protecting and improving livestock industry in the countries that depend on a high number of small ruminants.

  相似文献   
63.
Methods are described for the determination of acidic herbicides and related compounds in water and soil. Eight acidic herbicides and related compounds were extracted from water using either dichloromethane or an XAD-2 resin column. The acidic moieties were derivatized with 2-cyanoethyldimethyl(diethyl)aminosilane. The derivatized compounds were separated using capillary gas chromatography and quantitated using a nitrogen-phosphorus detector. Extraction from water using dichloromethane or an XAD-2 resin column resulted in recoveries greater than 90% at 0.1 ppb with an average coefficient of variation (CV) of 6%. In soils extracted with aqueous acetonitrile-acetic acid and partitioned into dichloromethane, recoveries at 500 ppb were greater than 75% with an average CV of 3.3%. The methods are rapid and there are few interferences.  相似文献   
64.
The efficient use of water by modern irrigation systems is becoming increasingly important in arid and semi-arid regions with limited water resources. This study was conducted for 2 years (2005 and 2006) to establish optimal irrigation rates and plant population densities for corn (Zea mays L.) in sandy soils using drip irrigation system. The study aimed at achieving high yield and efficient irrigation water use (IWUE) simultaneously. A field experiment was conducted using a randomized complete block split plot design with three drip irrigation rates (I1: 1.00, I2: 0.80, and I3: 0.60 of the estimated evapotranspiration), and three plant population densities (D1: 48,000, D2: 71,000 and D3: 95,000 plants ha−1) as the main plot and split plot, respectively. Irrigation water applied at I1, I2 and I3 were 5955, 4762 and 3572 m3 ha−1, respectively. A 3-day irrigation interval and three-way cross 310 hybrid corn were used. Results indicated that corn yield, yield components, and IWUE increased with increasing irrigation rates and decreasing plant population densities. Significant interaction effects between irrigation rate and plant population density were detected in both seasons for yield, selected yield components, and IWUE. The highest grain yield, yield components, and IWUE were found for I1D1, I1D2, or I2D1, while the lowest were found for I3D2 or I3D3. Thus, a high irrigation rate with low or medium plant population densities or a medium irrigation rate with a low plant population density are recommended for drip-irrigated corn in sandy soil. Crop production functions with respect to irrigation rates, determined for grain yield and different yield components, enable the results from this study to be extrapolated to similar agro-climatic conditions.  相似文献   
65.
Summary

Overhead irrigation is a common irrigation practice in nurseries, yet it can be wasteful of water and nutrients. We compared the water use, fertilizer use and growth of ‘Top Gun’ lettuce (Lactuca sativa L.) and ‘Grosse Lisse’ tomato (Lycopersicon esculentum Mill.) seedlings in sub and overhead irrigation systems. Five rates of controlled release fertilizer were used – 0.625, 1.25, 2.5, 5 and 10 kg m–3. Sub-irrigation used 86% less water than overhead irrigation. Irrigation type had a significant effect on some growth measurements by final harvest, 43 d after sowing. The sub-irrigated lettuce seedlings were significantly taller. The overhead irrigated lettuce seedlings had a higher dry weight and more leaves. The sub-irrigated tomato seedlings were taller, had longer leaves, a larger leaf area and more leaves. Increasing levels of controlled release fertilizer produced quadratic type responses over time for shoot dry weight, with 10 kg m–3 producing tomato and lettuce transplants with a higher biomass in a shorter time than lower levels of fertilizer.  相似文献   
66.
The trnL (UAA) intron and the intergenic spacer between the 3′ exon of trnL (UAA) and trnF (GAA) sequences were used as genetic markers for differentiating Ficus carica cultivars and establishing refined genetic relationships. The study was based on 20 fig cultivars, collected from south and centre of Tunisia. Since, the intron was thought to be more variable among close relatives than is the chloroplast spacer. The size of these non-coding regions varied from 554 to 589 and from 989 to 1022 bases pairs for the intron and the combined sequences correspondingly. The average of GC content was 33.9% and 34.6% in the intron and the combined intron and spacer respectively. High values of A + T contents were detected in both data sets and may explain the high proportions of transversions founded. The observed variation pattern of plastid DNA provides evidence of an important genetic diversity. The overall transition/transversion bias (R) was 0.202 in the intron and 0.27 in the combined regions. The RI index of 0.592 indicates that these combined sequences have clearly more homoplasy then the intron (RI = 0.705) and spacer (RI = 0.777) sequences separately. Phylogenetic trees were generated based on maximum parsimony (MP) and neighbor-joining (NJ) analysis of the chloroplast sequences data. Results proved that a typically continuous genetic diversity characterizes the local fig germplasm. In fact, relationships inferred from the cpDNA analysis suggest several clades, which do not show geographical or tree sex correspondence. Although the level of apparent diversity is considerable, we may conclude that non-coding regions of chloroplast genome provide a new and practical opportunity to evaluate genetic diversity and to discriminate fig cultivars. Revealed cytoplasmic DNA markers are reliable to elaborate a molecular data base to conduct management and breeding programs on local fig germplasm.  相似文献   
67.

Purpose

Ornamentals can beautify the environment and resolve heavy metal pollution at the same time. Thus, the present study aimed at studying the growth and physiological response of Tagetes patula on iron ore tailings.

Materials and methods

Pot-culture experiments were conducted to investigate the effect of iron ore tailings both individually as well as in combination with soil (at different proportions) on the growth, pigment production as well as accumulation and translocation of various heavy metals from the tailings.

Results and discussion

The results suggested an increase in growth, chlorophyll content, as well as metal accumulation capacity of T. patula with increasing proportion of tailings in the soil. Furthermore, an increase in antioxidant activities in plants grown on tailings as compared to control was observed which suggests plant efficiency to overcome any stress generated due to excess of heavy metals. The order of accumulation of various heavy metals in the plant parts was observed to be Fe?>?Cr?>?Zn?>?Cu?>?Pb?>?Ni?>?Cd. Both bioaccumulation and translocation values were maximum for Fe and minimum for Ni and Cd, respectively.

Conclusions

The overall study clearly suggests plant ability to grow well on the tailings and survive excess of heavy metals present in the tailings. Thus, the plant qualifies well as a potential tool for phytostabilization of iron ore tailings and probably a source of income generation from wasteland owing to its multiple commercial values.  相似文献   
68.
The present study was conducted to evaluate the …effect of dietary selenium on growth performance and antioxidant enzymes activity in Cirrhinus mrigala for a period of 45 days. Four numbers of experimental diets were prepared, Tc for Control (0 mg organic selenium/kg of diet), T1 (2.5 mg organic selenium/kg of diet), T2 (5.0 mg organic selenium/kg of diet) and T3 (10 mg organic selenium/kg of diet). The water quality parameters (temperature, DO, pH, conductivity, hardness, ammonia, nitrate and nitrite) were found to be insignificant (p > .05) among all the treatments. Superoxidase dismutase (SOD) was found to be significantly highest in T2 (6.10 ± 0.07) when compared with the other treatments. Similarly, catalase (CAT) activity in T1 (13.21 ± 0.13) was significantly (p < .05) different with that of Control, T2 and T3. Present study also revealed that 2.5mg organic selenium/kg supplemented diet (T1) showed highest results in net weight gain (15.55 ± 1.36 g), net weight gain percentage (185.88 ± 8.98%) and SGR (2.35 ± 0.06 g) compared with other experimental diet.  相似文献   
69.
Despite the importance of mucilage for soil–plant relations, little is known about the effect of soil drying on mucilage exudation. We introduce a method to collect mucilage from maize growing in wet and dry soils. Mucilage was collected from brace roots. The amount of mucilage exuded did not change with soil water content and transpiration rate. Mucilage exuded in dry soils had a higher degree of hydrophobicity, suggesting that the wetting properties of mucilage change in response to soil drying.  相似文献   
70.
The efficacy of copper sulphate (CuSO4) against the early stages of an experimental acute infection of Flavobacterium columnare in channel catfish (Ictalurus punctatus) was evaluated. Fish were challenged, by waterborne exposure to F. columnare in an ultra‐low flow‐through water delivery system, and treated with CuSO4 at 4.2 and 2.1 mg L?1 at 5.5 h post challenge for 4 h. Bacterial challenged non‐treated fish acted as a positive control and non‐challenged non‐treated fish acted as a negative control. Fish challenged with F. columnare and treated with CuSO4 at 4.2 and 2.1 mg L?1 post challenge had mortalities of 6.4% and 18.3%, respectively, compared with the positive control, which had 90.2% mortality. The mortality of challenged fish treated with CuSO4 at 4.2 and 2.1 mg L?1 was significantly different from the positive control. There was no significant difference between the mortalities of the 4.2 and 2.1 mg L?1 treatments. The results suggest that CuSO4 has clear therapeutic value against columnaris infections.  相似文献   
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