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151.

Purpose

The aim of this study was to determine the mutual relations between polycyclic aromatic hydrocarbons (PAHs) originated from atmospheric emissions and enzymatic activity and humic substances in soils at differently urbanized area, on an example of the Lublin city, east Poland.

Materials and methods

The chosen areas represented three differently urbanized environments: old tenement houses and modern residential blocks, mixture of different building and rural landscape, and typical rural environment with smallholding farms, respectively. On each of the urban, suburban, and rural areas, one representative plot was chosen on fallow lands classified as luvisol derived from loess. The soil samples were collected from the top 25 cm layer. The following properties were determined: pH, organic carbon, total nitrogen, humic and fulvic acids, PAHs content (14 PAHs from US EPA list), and the activities of the following enzymes: dehydrogenases, acid phosphatase, alkane phosphatase, protease, and urease.

Results and discussion

Higher contents of organic C and total N were found in the rural soil samples. The share of humic acid was similar in all soils investigated, ranging from 19.38 to 25.27%, while fulvic acid values differ significantly between urban and rural areas. The urban soils indicated much lower share of fulvic acids (9.78–10.99%) than those of rural (29.02–29.32%). Consequently, the values of the CHA:CFA ratio of the urban soil were approximately two times higher than those of the rural soil. The results showed that both the rate of humification and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases in the soils increased in the following sequence: urban < suburban < rural.

Conclusions

The results showed that an increase of PAHs in the urbanized areas affect other soil properties. The phenanthrene/anthracene and fluoranthene/pyrene ratios pointed to coal combustion as the principal source of PAHs in the investigated soils. The PAH content in the urbanized area inhibit humification processes in the soil and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases.
  相似文献   
152.
The aim of this study was to estimate the genetic parameters and inbreeding effect on the fertility, embryo mortality and hatchability traits in the Zatorska goose covered by the animal genetic resources conservation program. The material for this study contains information about results of hatching of 18 863 eggs from 721 dams and 168 sires, laid between 1998–2015. Genetic parameters were estimated based on the threshold animal model by the use of Restricted Maximum Likelihood and Gibbs sampling. The percentage of fertilized eggs ranged yearly between 37–80%. The percentage of embryo mortality was very low, ranging between 4.63–23.73%. The percentage of the hatched goslings from the total number of analyzed eggs was on average 33.18%, and 53.72% from fertilized eggs. On average based on both methods, the heritability estimates of the fertility, embryo mortality and hatchability reached 0.36, 0.07, 0.24 for males and 0.44, 0.11, 0.32 for females. The genetic trend had increasing tendency for fertility and hatchability and was stable for embryo mortality for both sexes. The obtained result shows that the Zatorska goose can be still maintained in the reserves of the local gene pool according to current rules and use in the local market as a breed with good reproductive potential.  相似文献   
153.
The aim of this experiment was to determine what dosage of copper (Cu) nanoparticles, added to a standard dietary supplementation with copper sulfate, would improve antioxidant and immune defense in chickens. The experiment was conducted with 126 broiler chickens assigned to seven treatments with three pens per treatment and six broiler chickens per pen. The basal‐diet treatment did not receive Cu nanoparticles (nano‐Cu) and as shown by analyses it was Cu‐deficient (?29% vs. National Research Council (NRC) recommendations; 5.7 vs. 8 mg/kg). Broiler chickens received nano‐Cu (0.5, 1.0 or 1.5 mg/kg body weight per day) via a tube into the crop over three 3‐day periods (days 8–10, 22–24 and 36–38) or three 7‐day periods (days 8–14, 22–28 and 36–42). As a result, in the nano‐Cu‐treated broilers the total experimental Cu intake was from ?11% to +96% versus NRC recommendations. At the age of 42 days of broilers, their blood indices were determined. The obtained results showed that correction of the deficient basal diet of chickens with nano‐Cu to a level of copper exceeding the NRC recommendation by 54% increased the antioxidant potential of the organism and inhibited lipid peroxidation. At the dosage of +96% versus NRC, some symptoms of a deterioration in antioxidant status appeared (a decrease in the level of glutathione plus glutathione disulfide and an increase in superoxide dismutase, catalase and ceruloplasmin activity and in lipid hydroperoxide content). Additionally, +7% versus the recommended Cu dietary level was followed by unfavorable results, indicating a deterioration in red blood cell parameters and stimulation of the immune system (an increase in interleukin‐6, immunoglobulin A (IgA), IgM and IgY). To conclude, it was shown that it is possible to simultaneously increase antioxidant and immune defense of chickens by supplementing their diets with nano‐Cu – up to 12 mg per bird during 6 weeks of feeding, that is to a level no more than 7% over the NRC recommendation for growing broiler chickens.  相似文献   
154.
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156.
The present study was aimed at identifying the key thermographic diagnostic areas essential for monitoring the effect of training on racehorses. The study involved monitoring 15 racehorses in 13 imaging sessions over a period of 10 months. Temperature measurements were made at a total of 46 regions of interest (ROIs) at the distal parts of the limbs and the back. To account for the influence of ambient temperature on each ROI measurement, values were adjusted to a constant ambient temperature of 12°C, estimated using regression analysis. The horses in the study were divided into two groups based on the value of success rate in racing competition. During the research period, none of the horses were identified as injured by routine veterinary investigation. Successful horses had significantly warmer adjusted ROI temperatures than their less successful counterparts at both carpal joints, the third metacarpal bones, the left fetlock joint, the left front short pastern bone, the left tarsus joint, and the caudal part of the thoracic vertebrae. The study tested a protocol for recording body surface temperature in racehorses, which was shown to increase reliability by adjusting for variations in ambient temperature. When analyzed on the basis of sporting performance, the protocol identified 14 ROIs that were associated with superior performance, most of which were at the limbs on the left side.  相似文献   
157.
Cyprinid herpesvirus 3 (CyHV-3) causes a lethal disease in common and koi carp (Cyprinus carpio). The present study investigated the ability of CyHV-3 to infect common carp during the early stages of its development (from embryos to fingerlings) after inoculation by immersion in water containing the virus. Fish were inoculated at different times after hatching with a pathogenic recombinant CyHV-3 strain expressing luciferase. The sensitivity and permissivity of carp to CyHV-3 were investigated using in vivo bioluminescence imaging. The susceptibility of carp to CyHV-3 disease was investigated by measuring the survival rate. Carp were sensitive and permissive to CyHV-3 infection and susceptible to CyHV-3 disease at all stages of development, but the sensitivity of the two early developmental stages (embryo and larval stages) was limited compared to later stages. The lower sensitivity observed for the early developmental stages was due to stronger inhibition of viral entry into the host by epidermal mucus. In addition, independent of the developmental stage at which inoculation was performed, the localization of light emission suggested that the skin is the portal of CyHV-3 entry. Taken together, the results of the present study demonstrate that carp are sensitive and permissive to CyHV-3 at all stages of development and confirm that the skin is the major portal of entry after inoculation by immersion in infectious water. The results also stress the role of epidermal mucus as an innate immune barrier against pathogens even and especially at the early stages of development.  相似文献   
158.
A hypophysial homogenate injection increased blood gonadotropin level in adult female carp and maintained it at that level for three days after injection.The blood gonadotropin level in adult female carp seems to be dependent on the physiological condition of the ovary expressed by the relation of old oocytes with a completed vitellogenesis process to the new ones, and the relation of the oocytes with the nucleus shifted to the periphery to those with a centrally placed nucleus.  相似文献   
159.
The aim of this study was to compare four micronutrient soil-test extractants currently in common use in Poland, Rinkis, Mehlich 3, modified Lindsay and Norvell, and Yanai, for ability to determine the plant-available concentration of copper (Cu) and manganese (Mn) in two acidic soils (pH 4.8–4.9) that had been amended with different doses of Cu and Mn fertilizers. The comparison was based on two pot experiments (each with a different soil) with corn (Zea mays), barley (Hordeum vulgare), spring wheat (Triticum aestivum), rape (Brassica napus), red clover (Trifolium pratense), and English ryegrass (Lolium perenne). The extractants were evaluated based on a correlation analysis of the microelement concentrations in plants at the end of the vegetative phase and micronutrient concentration in the fertilized soil determined by each extractant at the end of the experimental period. The largest extractable concentrations of Cu and Mn in soils were obtained with Rinkis. The modified Lindsay and Norvell soil test extracted the lowest amount of both microelements. For soil Cu, the results with the Mehlich 3 and Yanai extractants were highly correlated with the Rinkis procedure results (r = 0.98). The modified Lindsay and Norvell results were not as well correlated with Rinkis (r = 0.84). For soil Mn, the correlation of results of Yanai, Mehlich 3, and modified Lindsay and Norvell to Rinkis ranged from r = 0.80 to r = 0.86. Levels of Mn and Cu measured with each of the extractants were highly correlated with plant tissue concentrations of Mn and Cu in most of the six plant species. The exceptions to this were the following: The modified Lindsay and Norvell soil Cu levels were not correlated with ryegrass and wheat plant Cu levels; Mehlich 3 Cu was not correlated with red clover Cu; and the Rinkis-extractable Mn was not correlated with the wheat Mn. It is concluded that the Yanai and Mehlich 3 procedures are suitable alternatives to the Rinkis for Cu but not for Mn.  相似文献   
160.
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