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1.
Ultrasonography of the liver was performed in 200 Holstein-Friesian dairy cattle using a 3.5 MHz transducer with a linear array electronic scanner. Liver samples were taken, processed and examined microscopically and the fat occupying rate was calculated. The hepatic ultrasonograms were evaluated according to the presence of bright pattern, dark pattern, deep attenuation, vascular blurring and blurring of edges. Of the 200 animals, 96 had a normal liver, 63 had hydropic degeneration of the liver, 37 had fatty infiltration of the liver, 3 had liver dystrophy and I had hepatic amyloidosis, diagnosed through histopathological examination. Amyloidosis was characterized by bright pattern and blurring of edges. Liver dystrophy had higher percentages of bright pattern and blurring of edges than normal liver. Hydropic degeneration had higher percentages of dark pattern and blurring of edges than normal liver. Fatty infiltration had higher percentages of bright pattern, deep attenuation, vascular blurring and blurring of edges than normal liver. The present results suggest that different ultrasonographic patterns can be observed in various diffuse hepatocellular disorders in dairy cattle  相似文献   
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Tropical Animal Health and Production - Avian influenza virus (AIV) H9N2 subtype is endemic in Iran and causes substantial economic loss to the growing poultry industry within the country. In this...  相似文献   
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The objective of this study was to consider endocannabinoid system as inflammatory markers in bovine endometrium to better understand the role of this system in regulating many of the functions that are related to inflammatory condition. At day 26 post‐partum, fourteen cows were divided into two groups depending on the inflammatory condition: 1‐ subclinical endometritis (n = 7, with purulent or mucopurulent uterine discharge detectable in the vagina) and 2‐ healthy (n = 7, No (muco)) purulent discharge. Blood samples were collected at 26 and 30 days relative to calving to determine plasma tumour necrosis factor (TNF) and lipopolysaccharide‐binding protein (LBP) concentrations; moreover, uterine biopsy was carried out on day 26 post‐partum to measure mRNA abundance of TNF, interleukin‐1B (IL1B), interleukin‐6 (IL‐6), C‐X‐C motif chemokine ligand 8 (CXCL8), endocannabinoid receptor (CNR2), N‐acyl phosphatidylethanolamine phospholipase D (NAPEPLD), fatty acid amide hydrolase (FAAH), N‐acylethanolamine acid amidase (NAAA) and monoglyceride lipase (MGLL) by real‐time PCR. Results showed mean plasma concentrations of TNF and LBP were lower in healthy cows compared to subclinical endometritis cows (p < .05). Relative mRNA expression for NAAA and FAAH was decreased (p < .05), and relative mRNA expression for CNR2 and NAPEPLD increased in cows with subclinical endometritis compared to healthy cows. In conclusion, relative mRNA expression of TNF, IL1B and CXCL8 and plasma concentration of LBP increased during inflammatory condition along with decreased endocannabinoids hydrolyzing enzyme (NAAA and FAAH), increased enzymes that synthesize endocannabinoids (NAPEPLD) and relative gene expression of the endocannabinoid receptor; together, these contribute to increased endocannabinoids levels during inflammation. Overall, we provide evidence that endocannabinoid system is altered in endometrium tissue during inflammation through increased mRNA expression of CNR2 and synthesis enzyme and decreased mRNA expression of hydrolyzing enzymes interfere with pro‐cytokine production and signalling, which may interfere with the onset and progression of inflammation.  相似文献   
4.
Decision support systems (DSSs) are indispensable tools in preparing a forest management plan for a better combination of multiple forest values. This study attempted to develop and explain a stand-based forest management DSS (Ecosystem-based multiple-use forest planning [ETÇAP]) comprising a traditional simulation, linear programming (LP), metaheuristics and geographic information system. The model consists of five submodels; traditional management approach to handle inventory data, an empirical growth and yield model, a simulation to conceptualize management actions, a LP technique to optimize resource allocation and a simulated annealing approach to directly create a spatially feasible harvest schedule. The ETÇAP model has been implemented in a comparative two case study areas; Denizli–Honaz and Akseki–Ibrad?. Both simulation and optimization models outperformed to the traditional management plan. The periodical change of growing stock, allowable cuts, carbon sequestration and water production are used as performance indicators. The results showed that more amount of wood could be harvested over time compared to traditional level of harvesting. It could be concluded that various management strategies allowed managers to stimulate more decision options for better outputs through intertemporal trade-offs of management interventions as the model provided tools to quantify forest dynamics over time and space. Challenges exist to establish the functional relationships between forest structure and values for better quantification and integration into the management plans.  相似文献   
5.
The present investigation was conducted to assess the ameliorative effects of foliar‐applied trehalose on growth, photosynthetic attributes, water relation parameters and oxidative defence mechanism in two maize cultivars under field water deficit conditions. Various components of the experiment comprised two maize cultivars (EV‐1098 and Agaiti‐2002), two water‐stress levels (irrigation after 2 weeks and irrigation after 3 weeks during the entire period of growth), and two levels of trehalose (0 and 30 mm ) and four replicates of each treatment. Water stress significantly reduced the plant biomass production, photosynthetic attributes and water relation parameters in both maize cultivars. In contrast, water stress considerably increased the leaf malondialdehyde (MDA) contents, the activities of antioxidant enzymes such as peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT), and the levels of non‐enzymatic compounds such as ascorbic acid and tocopherols. In contrast, water stress caused a marked reduction in leaf phenolic contents. Foliar‐applied trehalose significantly increased plant biomass production, and improved some key photosynthetic attributes and plant–water relation parameters. The ameliorative effect of exogenously applied trehalose was also observed on the activities of some key antioxidant enzymes (POD and CAT) and non‐enzymatic compounds (tocopherols and phenolics). Overall, exogenously applied trehalose considerably improved drought tolerance of maize plants by up‐regulating photosynthetic and water relation attributes as well as antioxidant defence mechanism.  相似文献   
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This study investigated the effects of low potassium diets with different levels of Ca compared to two diets low in dietary cation–anion difference (DCAD) fed prepartum as a strategy to prevent hypocalcemia on sorting behaviour, total tract digestibility, oxidative status and energy and protein metabolism of transition cows. Forty-eight pregnant dairy cows were assigned to 4 treatment groups: Low Ca, low K (LCLK), High Ca, low K (HCLK), Supplementation with anionic mineral mixture (AMS) supplementation with SoyChlor (CAS). After parturition, all animals were fed a standard postpartum diet. Data were collected until 21 DIM. Prepartum urinary pH was significantly reduced by the low DCAD diets, while postpartum Ca homeostasis was affected by the HCLK ration. Feeding AMS induced sorting against particles <1.18 mm in favour of particles >19 mm prepartum. In contrast, cows fed CAS showed an increase in selective consumption of fine particles and sorted against longer particles similar to the HCLK and LCLK groups. Postpartum sorting activity was not affected by the dietary treatments. After calving, apparent digestibility of NDF was significantly reduced in the HCLK group. Prepartum, we observed effects on serum concentrations of non-esterified fatty acids were higher and insulin sensitivity was lower in the AMS group. Blood urea nitrogen (BUN) was decreased in cows fed the CAS ration. Postpartum, we found serum protein to be decreased with the low DCAD diets while BUN was decreased in the CAS group. The low DCAD rations increased prepartum serum malondialdehyde concentrations, while postpartum total antioxidant capacity was lower in the HCLK and the AMS group. From these data, we conclude that AMS decreased prepartum intake due to compromised palatability. Intermediate protein metabolism was affected by the low DCAD diets, while parameters of oxidative stress were probably affected by acid–base balance and Ca homeostasis.  相似文献   
10.
Recent studies have demonstrated a strong relationship between the intestinal microbiota and the host health. As such, consumers are increasingly becoming more concerned about the potential effect of certain foods/feeds, particularly of transgenic origin on the gut microbiota. Although the European Food Safety Authority has recommended in their guidelines, to study the effect of transgenic food/feed on host-microbiota, yet, few studies have focused on the evaluation of such effects mainly due to culturing difficulties. Therefore, this study was intended to evaluate the potential adverse effects of transgenic diet consumption on some specific gut microflora (Lactobacillus group, Bifidobacterium genus, Escherichia coli subgroup and Enterococcus genus) of rabbits. A total of forty-eight rabbits were randomly assigned into four groups and fed a diet containing a variable proportion of transgenic cottonseeds at 0, 20, 30 and 40% inclusion level, respectively. Changes in the specific or total faecal bacterial population were monitored at five different experimental stages (i.e. 0, 45, 90, 135 and 180 days) using both the traditional plate count method (TM) and quantitative real-time PCR (qPCR). No significant differences (p > .05) were observed concerning numbers of specific bacteria or total bacteria between the control and experimental groups, though qPCR showed numerically higher values in terms of 16S rRNA gene copies as compared to the values obtained from TM. However, such numerical differences were biologically insignificant (p > .05). Similarly, no significant variations were noticed in the calculated B/E (log10 copies of Bifidobacterium per g faces/log10 copies of E. coli genome per g faeces) ratios in all the groups. All the ratios were in the range of 1.24 to 1.30 throughout the experiment, indicating a good balance of intestinal microflora and greater resistance to intestinal disorders. It is therefore concluded that feeding transgenic cottonseeds could not adversely affect the gut microflora of rabbits during a long-term study.  相似文献   
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