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11.
Tropical Animal Health and Production - Corn gluten feed (CGF) is a co-product of wet milling that can replace energy or fiber ingredients in dairy cow rations. The present meta-analysis examines...  相似文献   
12.
A biological assay was carried out to evaluate the impact of dietary tryptophan (TRP) in aflatoxin B1‐contaminated diets (AFB1‐D) on performance, blood parameters, immunity, meat quality and microbial populations of intestine in Japanese quails. Six experimental diets were formulated to include two levels of dietary TRP; 2.9 (moderate high: MH‐TRP) and 4.9 g/kg (excess: Ex‐TRP); and three levels of AFB1 (0.0, 2.5, and 5.0 mg/kg). Each experimental diet was fed to the one of the six groups of birds from 7 to 35 days of age in a completely randomized design with 2 × 3 factorial arrangement. Decrease in feed intake, body weight gain and gain:feed in birds fed 5.0 mg/kg AFB1‐D was restored to the control level by 4.9 g TRP/kg of the diet. The hepatic enzymes in blood were elevated in quails fed on AFB1‐D but attenuated by 4.9 g TRP/kg of the diet (Ex‐TRP; p ≤ .01). High serum uric acid in birds challenged with AFB1 significantly decreased by Ex‐TRP (p ≤ .01). The skin thickness to 2,4‐dinitro‐1‐chlorobenzene challenge suppressed by AFB1 but increased by Ex‐TRP diet (p ≤ .02). The AFB1 increased the malondialdehyde in meat, whereas TRP efficiently diminished malondialdehyde production (p ≤ .01). The greatest drip loss and pH in meat were observed in the birds fed 5.0 mg/kg AFB1‐D but Ex‐TRP augmented the adverse effects of AFB1 (p ≤ .01). The Ex‐TRP reduced the total microbial and Escherichia coli counts (p ≤ .01). The adverse effect of AFB1 on ileal Lactic acid bacteria was completely prevented by Ex‐TRP (p ≤ .03). This study showed that tryptophan supplementation could be considered as a powerful nutritional tool to ameliorate the adverse effects of AFB1 in growing quails.  相似文献   
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The aim of the present study was to investigate the normal blood parameters of Iranian fat-tailed sheep (Zandi) and their changes due to rapid liver biopsy technique with a tru-cut biopsy needle. In ten ewe lambs, blood samples were collected from jugular vein and biopsy needle was inserted through the dorsal one third of the 11th intercostal space, on the right hand side of the lambs and liver specimen was collected. Physical examinations were performed on alternate days during the experiment. Blood collection was done on both before (day 1) and after (day 17) the biopsy. All animals were slaughtered at day 17. Values were compared using paired t test. While biopsy did not make any significant changes in mean values of body temperature, heart rate, respiratory rate, PCV, WBC, neutrophil, lymphocyte, eosinophil, monocyte, total serum protein, AST, ALT, and serum calcium (p > 0.05), it made a significant difference on the values of ALP (p < 0.001), serum inorganic phosphate (p = 0.035), and magnesium (p = 0.013). Necropsy examination revealed the points of hitting the biopsy needles on the diaphragmatic surface of the livers, surrounded by a zone of intense hyperemia. Peritoneal adhesions accompanying with typical strands of fibrous connective tissue between diaphragmatic surface of the liver and adjacent abdominal wall were found in two cases.  相似文献   
15.
This study was undertaken to compare patterns of agronomic characters and yellow pigment content diversity between Iranian durum landraces and modern varieties. In four field experiments, a collection of 127 accessions of landraces and 23 modern cultivars tetraploid wheat representing Iranian and global genetic diversity were tested under optimum and rain-fed conditions. Across the environments, the yellow pigment concentrations ranged from 1.85 mg kg?1 to 8.95 mg kg?1 in the field-grown samples. Multivariate analysis detected five groups, four including landraces and one comprising modern cultivars. As a group, modern cultivars were the most productive and showed high mean values for harvest index, grains per spike and yellow pigment, but they had the lowest plant height. Landraces had the highest mean number of spikes per m2 and 1000-kernel weight, but were characterized by low plant height and yellow pigment content. Clustering analysis also showed that, based on yield and yellow pigment content, the accessions in different groups were of different origins, suggesting that there was no clear relationship between accessions and geographical diversity. According to our results, Iranian landraces can be particularly useful as germplasm in breeding programmes to improve spikes per m2 and 1000-kernel weights.  相似文献   
16.
To investigate the effects of agronomic practices and farmer demographics on levels of weed infestation in chickpea fields, a survey was conducted during 2015 in Sanjabi district, Kermanshah, Iran. Two sets of data were collected: (a) weed sampling from the selected chickpea fields, and (b) questionnaire recording of farmer demographics and agronomic management. The farmers were asked about their residence status (resident or migrant), occupation (farming only, farming plus a second job), experience and education levels, as well as seedbed preparation, sowing date and method, source of seed supply, crop cultivar, sowing seed rate, weed control operation and crop rotation history. The results showed that weed species composition was similar across the studied fields. The use of a row crop planter, a sowing rate of 45 kg ha‐1, and weed control resulted in 30.2, 23.03 and 34.2% reductions in weed infestation compared with hand sowing, a sowing rate of 30 kg ha‐1 and lack of weed control, respectively. Weed density decreased with increasing farmer experience and decreased by 33.0% and 23.5% in chickpea fields of resident farmers and owners whose sole occupation was agriculture. We found that 89.5% of the most experienced farmers adopted weed control operations and most resident landowners (77.4%) opted for crop planter (77.4%) and weed control (90.3%) compared to migrant farmers (50 and 68.5%, respectively). More landowners who were exclusively farmers performed weed control (90.6%) than owners who had a second job (67.9%).  相似文献   
17.
Background: Oxidative modification of low-density lipoprotein (LDL) appears to be an early step in the pathogenesis of atherosclerosis. Meanwhile, myeloperoxidase (MPO)-catalyzed reaction is one of the potent pathways for LDL oxidation in vivo. The aim of this study was to evaluate in vitro antioxidant effects of vitamins C and E on LDL oxidation mediated by MPO. Methods: MPO was isolated from fresh plasma by sequential centrifugation using density ultracentrifugation. It was incubated with LDL and the LDL oxidation level was determined spectrophotometrically by measuring conjugated diene absorbance at 234 nm. Furthermore, vitamin C (50-200 mM) and vitamin E (10-40 mM) were added and the LDL oxidation level was determined. Results: The purity index of MPO and its enzymatic activity were 0.69 and 1127 U/mg protein, respectively. It was demonstrated that vitamin C in vitro inhibited LDL oxidation mediated by MPO; however, vitamin E was unable to act in the same way. The protection by vitamin C was concentration dependent and maximum protective effect of vitamin C was observed at 150 mM, where about 64% of the LDL oxidation was inhibited. Vitamin C increased lag time of LDL oxidation mediated by MPO up to 2.4 times. Conclusion: It can be concluded from our results that vitamin C is able to improve LDL resistance to oxidative modification in vitro. In addition, vitamin C might be effective in LDL oxidation mediated by MPO in vivo, resulting in reduction of atherosclerosis process rate. Key Words: Antioxidant, Myeloperoxidase (MPO), Low-density lipoprotein (LDL), Vitamin E  相似文献   
18.
Maedi-visna (MV) is an important slow viral disease of sheep leading to a progressive lymphoproliferative disease. It affects multiple organs primarily the lungs, where it causes interstitial pneumonia (maedi). In this study, the lungs of 1,000 sheep carcasses were grossly inspected and those suspected to have maedi were studied at histopathological and molecular levels. A polymerase chain reaction (PCR) technique that amplified a 291-base pair DNA in the long terminal repeat (LTR) sequence of MV provirus was conducted on all the 50 suspected lungs together with 10 normal appearing lungs as controls. Amplicons of the expected size were detected in 11 (n = 11/50) suspected sheep, and one of the 10 control sheep. Histopathologic study of the pulmonary lesions of all 11 (n = 11/11) positive sheep showed MV lesions, including hyperplasia of the perivascular and peribronchiolar lymphoid cells, interstitial lymphoplasmacytic infiltration and smooth muscle hyperplasia and the histopathologic findings were correlated with PCR results. In contrast, the tissue sections of control animals were almost normal at histopathological level; however, PCR technique demonstrated that one of them was affected by maedi. This study showed that the LTR-PCR had high specificity and sensitivity in diagnosis of this viral infection. This study is the first to evaluate the prevalence of MV virus infection in sheep in Iran.  相似文献   
19.
BACKGROUND: When fetal red cells enter the maternal circulation from placenta, an event would be happened that is described as feto-maternal hemorrhage (FMH). This life-threatening condition could be detected by using RBC antigens (surface antigens and intracellular antigens). Therefore, the measurement of fetal RBC in an artificial model would be useful to calculate FMH and consequently the dosage of Rhogam for prophylaxis. The aim of the present study was to evaluate FMH in an artificial mixture model. METHODS: A series of 40 artificial specimens were prepared consisting of Rh(D) negative adult blood (non-immunized) spiked with varying amounts of Rh(D) positive cord blood from mothers between 20-30 years old in Shahid Beheshti Hospital, Tehran, Iran. Monoclonal anti-D and anti-HbF (fetal hemoglobin) were used for detection of fetal RBC in artificial mixture sample modeling. RESULTS: This study showed that the percentage of fetal cells in artificial sample for anti-D antigen is in ranges of 0.28%-0.32% for a 0.25% dilution mixture, and 1.3%-2.05% for the mixture with dilution 2%. In addition, the ranges of data for anti-HbF staining was obtained 0.2%-0.34% for the 0.25% dilution sample, and the ranges of 1.04-1.8% for the 2% dilution. The regression analysis indicated that the correlation of anti-D assessment with expected standard method was r2 = 0.9672 and anti-HbF assessment was r2 = 0.8842. CONCLUSION: Although both molecule targets could be used for detection of fetal RBC, in this model, anti-D staining was more accurate than anti-HbF staining. However, since anti-D can not be utilized for low-density or weak phenotype and other incompatibility, the anti-HbF labeling could be used for all FMH.  相似文献   
20.
The objective of present study was to record the sequential alterations in liver echo-texture through digital analyzing of the B-mode ultrasonography in three groups of under-conditioned (UC), moderate-conditioned (MC), and over-conditioned (OC) clinically healthy Holstein cows from 30 days to calving until 30 days in milk. Furthermore, to compare their changes in association with the changes of fat mobilization parameters of non-esterified fatty acids (NEFA), betahydroxybutyric acid (BHBA), and body condition score (BCS). Although the cows lost significant (P < 0.05) BCS from calving and the NEFA values showed an increasing trend near calving and the BHBA values significantly inclined postparturition, the mean grey scale histogram (MGSH) of liver images did not reveal significant fluctuations unless a significant decrease on calving day (P < 0.05). The MGSH drop was predicted to be the result of anatomical changes in abdominal cavity, related to delivery and liver’s blood flow. OC cows had higher NEFA on day +20 than UC and MC cows (P < 0.05). UC cows showed higher MGSH values on day −30 than MC cows and again on day −10 comparing to MC and OC cows (P < 0.05). MGSH values correlated with BCS values (r UC = −0.186; r MC = −0.283; r OC = −0.158). It was concluded that the studied cows did not show significant alterations in textural changes in their liver ultrasound whilst going through fat mobilization. As quantitative ultrasonography has shown the potential to detect cases of fatty liver, it could gain the attention to become a feasible device for liver health monitoring on a herd basis.  相似文献   
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