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951.
By the radiographic examination of pet and wild birds, veterinary clinicians may relatively easily obtain additional information that can be used routinely in their everyday diagnostic and therapeutic work. The first part of the present review summarizes the basic technical conditions of radiological examinations, analyses the radiographic features of healthy birds, and describes the procedure and radiological indications of contrast radiography.  相似文献   
952.
Carrots were grown on soils polluted by heavy metal salts. Each particular microelement reached a high concentration [molybdenum (Mo) 39.00, cadmium (Cd) 2.30, lead (Pb) 4.01, mercury (Hg) 30.00, and selenium (Se) 36.20 mg/kg dry matter] in the carrot. In a metabolic balance trial conducted with 15 male and 15 female New Zealand White rabbits, the control animals (n = 5) were fed ad libitum with concentrate as basal diet, while the other rabbits received the basal diet and carrots containing the particular microelement. Blood samples were taken to determine the activity of serum enzymes. To investigate the metabolism of Mo, Cd, Pb, Hg and Se, samples were taken from the heart, liver, lungs, kidneys, spleen, ovaries/testicles, entire digestive tract, adipose tissue, femur, hair, faeces and urine. Carrot had significantly higher digestibility for all nutrients than the rabbit concentrate. Carrot samples of high Pb content had the lowest digestibility of crude protein. The microelements differed in their rate of accumulation in the organs examined: Mo and Cd accumulated in the kidneys, Pb in the kidneys, liver, bones and lungs, Hg in the kidneys and liver, while Se in the liver, kidneys and heart. The proportions of microelements eliminated from the body either via the faeces and urine (Mo 80.18% and Se 47.41%) or via the faeces (Cd 37.86%, Pb 66.39%, Hg 64.65%) were determined. Pathohistological examination revealed that the rate of spermatogenesis was reduced in the Mo, Cd, Pb and Hg groups compared to the control. Lead, Cd and Hg intake resulted in a considerable decrease in gamma-glutamyltransferase (GGT) and in an increase of alkaline phosphatase (ALP) activity because of damages to the kidneys and bones. All experimental treatments decreased the activity of cholinesterase (CHE) because of lesions in the liver.  相似文献   
953.
954.
为了克服确定作物需水量所遇到的困难,该文介绍一种简单、可靠、易掌握、实用的生物气候测定方法.该方法根据被测地的土壤、气候和作物参数,得到玉米在生长季节的光水热系数平均值为0.15 mm/℃.该方法应用于南斯拉夫伏霍基拉省取得成功.由于光水热系数是由各地的特殊条件确定的,只要确定了该系数,该方法可在任何地方应用.灌溉时间和灌溉强度以及干旱的发生都可由该方法确定.玉米生长期的需水量为467 mm.  相似文献   
955.
Many predatory arthropods occur naturally in turfgrass, and they provide adequate control of lepidopteran pests, such as fall armyworm, Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), and black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae). Recording predation is challenging under field conditions because predators rarely leave any evidence. Clay models were successfully employed for studying predation, and this technique is underutilized in turfgrass. Little is known about whether the characteristics of clay models, such as color, shape, and size, influence arthropod interactions in turfgrass. To improve the utility of clay models in turfgrass, the influence of the color, shape, and size of clay models on arthropod interactions was studied by exposing clay models during daytime and nighttime in a turfgrass field. The results showed that arthropods interacted with clay models, and various types of impressions were recorded, including paired marks, scratches, cuts, and pricks. Although the color of the clay model had no significant effects on arthropod interactions during the night, significantly greater numbers of impressions were noticed on the blue and green models than on the yellow models during the daytime. The caterpillar-shaped models captured significantly greater densities of impressions than the beetle-shaped models. Additionally, the number of impressions significantly increased with an increase in the size of the model regardless of shape.  相似文献   
956.
The present study was to determine in vitro effect of levamisole on the immune functions of Barbel chub (Squaliobarbus curriculus), head–kidney‐derived (HKM), spleen‐derived (SM) and peripheral blood monocyte‐derived macrophage (PBM). Macrophages were incubated with levamisole 103, 101, 10−1 and 10−3 ng mL−1 to assay the cell viability, respiratory burst and phagocytosis. The results showed that macrophages treated with levamisole 10−3 ng mL−1 gave a maximum respiratory burst response, whereas levamisole 103 ng mL−1 had no effect. Phagocytosis activity of the macrophages treated with levamisole enhanced significantly when compared to control, maximum response being at 10−3 ng mL−1. While using the methylthiazoletetrazolium method to measure the cell activity for 12, 24, 36, 48, 60 h, there was no significant role on proliferation and the cell viability began to decline after 24 h. In conclusion, levamisole is a potent enhancer of Barbel chub macrophage activity with low concentration.  相似文献   
957.
This study was conducted to evaluate the effects of supplementation of crystalline methionine or coated methionine supplemented in diets of Pacific white shrimp (Litopenaeus vannamei) on growth performance and feed utilization. Five iso‐nitrogen and iso‐caloric diets were prepared in which diets were supplemented with cellulose‐acetate‐phthalate (CAP), tripalmitin‐polyvinyl alcohol (TPA), acrylic resin (RES) coated l ‐methionine, hydroxyl‐methionine calcium (MHA) and crystalline l ‐methionine diet (MET, control), respectively. After 7 weeks, shrimp (0.81 ± 0.01 g in initial body weight) weight gain fed with MET and RES diets were significantly higher than that of the others (P < 0.05), while feed conversion ratio of shrimp fed with RES was significantly lower than the others (P < 0.05). Crude protein (as wet weight basis) in whole body of shrimp fed the RES diet was markedly higher than the others (P < 0.05). Methionine contents in muscle of CAP and MHA groups were significantly higher than those of MET group (P < 0.05). Apparently digestibility for essential amino acid of MET group was the highest except methionine. In the present study, RES coating methionine appeared to effectively improve feed protein utilization and enhance growth performance of Pacific white shrimp fed with low fishmeal practical diet.  相似文献   
958.
The 8‐week experiment was conducted to evaluate the effects of partial replacement of fish meal (FM) with soybean protein concentrate (SPC) on juvenile black sea bream, Acanthopagrus schlegelii (10.70 ± 0.04 g). Diets were formulated to replace FM protein by SPC at 0, 8, 16, 24, 32 or 40% (designated as T1, T2, T3, T4, T5 and T6, respectively). Diets except T1 were supplemented with phytase at 2000 phytase activity U kg?1. The results showed that survival rate, growth performance and feed utilization were not significantly affected by increasing dietary SPC. Fish fed diet T3 had higher feed intake compared to those fed T1, T2 and T5 diets. Whole body compositions of black sea bream were significantly influenced by SPC replacing FM except for protein, ash and phosphorus content. Condition factor of fish was significantly lower in T2 than that of fish in T3 group. Apparent digestibility coefficients (ADCs) of dry matter was higher in fish fed T6 diet than those of fish fed T1 and T2 diets, ADCs of phosphorus increased with dietary SPC level up to T3 and then decreased. The results obtained in this study indicate that FM protein could be effectively replaced by SPC protein with phytase in diet of black sea bream.  相似文献   
959.
960.
This study was conducted to evaluate the potential of graded levels of GroBiotic®‐A to improve performance of Nile tilapia, Oreochromis niloticus, fed a 29% crude protein (CP) diet. A 29% CP diet was formulated and supplemented with 0, 0.4, 0.8, and 1.2% GroBiotic®‐A and compared to performance of fish fed a 33% CP diet. Enhanced weight gain and feed efficiency were generally observed in fish fed the diets supplemented with GroBiotic®‐A compared to the 29% CP diet. No significant differences in these responses were observed between fish fed diets supplemented with GroBiotic®‐A compared to those fed the 33% CP diet. Supplementation of 0.8 and 1.2% GroBiotic®‐A induced significantly lower condition factor and hepatosomatic index compared to fish fed the 29% CP diet, but those values were similar to that of fish fed the 33% CP diet. GroBiotic®‐A supplementation and protein reduction had no effect on the viscerosomatic index of fish or moisture, lipid, and protein content of muscle samples. However, muscle ash increased significantly with protein reduction (29% CP diet), but GroBiotic®‐A supplementation (0.8 and 1.2%) reduced muscle ash content. Activities of catalase and superoxide dismutase were markedly reduced in fish fed GroBiotic®‐A (0.8 and 1.2%) compared to those fed the control diet. GroBiotic®‐A supplementation also induced significantly higher neutrophil oxidative radical production compared to fish fed the 29% CP diet, but no significant difference was observed in comparison with the 33% CP diet. After 8 wk of feeding, exposure to Aeromonas hydrophila for 3 wk resulted in 40% (0.4, 0.8% GroBiotic®‐A) and 27% (1.2% GroBiotic®‐A) mortality and reduced signs of disease, while 47% mortality was observed in fish fed the 29% CP diet. Based on the result of this study, it is concluded that 0.8 and 1.2% GroBiotic®‐A positively influenced growth performance and feed efficiency of tilapia fed diets containing 29% crude protein to levels comparable to fish fed the 33% CP diet. GroBiotic®‐A supplementation also significantly increased neutrophil oxidative radical production as well as resistance to Ae. hydrophila infection.  相似文献   
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