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排序方式: 共有19条查询结果,搜索用时 15 毫秒
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Immunological basis of differences in disease resistance in the chicken   总被引:9,自引:0,他引:9  
Genetic resistance to diseases is a multigenic trait governed mainly by the immune system and its interactions with many physiologic and environmental factors. In the adaptive immunity, T cell and B cell responses, the specific recognition of antigens and interactions between antigen presenting cells, T cells and B cells are crucial. It occurs through a network of mediator proteins such as the molecules of the major histocompatibility complex (MHC), T cell receptors, immunoglobulins and secreted proteins such as the cytokines and antibodies. The diversity of these proteins that mainly is due to an intrinsic polymorphism of the genes causes phenotypic variation in disease resistance. The well-known linkage of MHC polymorphism and Marek's disease resistance difference represents a classic model revealing immunological factors in resistance differences and diversity of mediator molecules. The molecular bases in any resistance variation to infectious pathogens are vaguely understood. This paper presents a review of the major immune mediators involved in resistance and susceptibility to infectious diseases and their functional mechanisms in the chicken. The genetic interaction of disease resistance with production traits and the environment is mentioned.  相似文献   
3.
The effect of phenylbutazone on gastric emptying in horses was determined by measuring serum concentrations of acetaminophen. Gastric emptying was determined in normal fasted horses (n = 6), horses given endotoxin intravenously (n = 6), horses given intravenous phenylbutazone (n = 6), and horses given intravenous phenylbutazone plus endotoxin (n = 6). The mean time to reach maximum serum acetaminophen concentration (Tmax), the maximum serum concentration (Cmax), and the area under the serum acetaminophen concentration versus time curve (AUC) were compared among treatment groups. Phenylbutazone did not alter gastric emptying in normal horses. Endotoxin caused a profound delay in gastric emptying, and pretreatment with phenylbutazone abolished this effect.  相似文献   
4.
The effect of metoclopramide on gastric emptying of a liquid marker in horses was evaluated by measuring serum concentrations of acetaminophen. Gastric emptying was determined in normal, fasted horses (n = 7), horses given endotoxin intravenously (n = 7), and horses given intravenous metoclopramide plus endotoxin (n = 6). The mean time to reach maximum serum acetaminophen concentration (Tmax), the maximum serum concentration (Cmax), and the area under the serum acetaminophen concentration vs time curve (AUC) were compared among treatment groups. Endotoxin caused a profound delay in gastric emptying, and pretreatment with metoclopramide significantly (P < 0.05) ameliorated this effect.  相似文献   
5.
This study was aimed to determine gene action for grain yield and yield‐related traits of newly developed tef populations under drought‐stressed and nonstressed conditions to improve drought tolerance. Ten crosses, along with the parents, were evaluated in the F2 generation under drought‐stressed conditions at Hastebo and Adigdad sites in 2015 and Dura site in 2016 and under nonstressed conditions at Dura site in 2016. Additive gene action predominantly controlled the inheritance of the grain yield and majority of the yield‐related traits under drought‐stressed and nonstressed conditions. Under both test conditions, the genotypes DZ‐Cr‐387 and 9415 were the best general combiners for increased grain yield and morphological traits. Conversely, genotype 222076 was the best general combiner for reduced maturity period only. The selected parents are novel genetic materials for tef breeding programmes to improve grain yield and morphological traits with reduced days to maturity for drought tolerance breeding. The family of the cross DZ‐Cr‐387 × 222076 was selected for high grain yield and early maturity in both the drought‐stressed and nonstressed environments.  相似文献   
6.
ABSTRACT

Malnutrition in children is a current global burden. A common snack for children is biscuits prepared from cereals. However, these types of biscuits have low protein content. Therefore, producing healthier biscuits enriched with essential amino acids (EAAs) and other micronutrients is of great interest to researchers and manufacturers. In this study, biscuits produced from low gluten wheat flour fortified with sturgeon fillet powder (SFP) in various mixing ratios (100:0, 95:5, 93:7, and 90:10, respectively) were investigated. The results revealed that the nutritional and proximate composition of biscuits were significantly (P ≤ 0.05) improved: moisture (6.77 ± 0.06–7.65 ± 0.06), protein (13.23 ± 0.35–17.12 ± 0.02), fat (15.57 ± 0.18–15.85 ± 0.25), ash (0.84 ± 0.07–0.92 ± 0.06), spread ratio (14.0 ± 0.92–14.33 ± 0.21), and hardness (2,057.90 ± 28.33–3,089.02 ± 51.53). Total amino acids were 6.91, 9.34, 10.32, and 10.58; and EAAs were 2.43, 3.97, 4.48, and 4.22 g/100 g for 0%, 5%, 7%, and 10% SFP, respectively. Leucine was the major amino acid with 5% and 10% SFP, while methionine was the major amino acid with 7% SFP. Fungal counts were not observed, and quality indices were below the maximum acceptable limits in the products. Biscuits supplemented with 7% SFP showed the highest sensory evaluation score. Overall, the inclusion of 7% SFP could produce protein enriched cereal-based fortified biscuits with acceptable sensory and quality attributes and ultimately could insure effective fish utilization and solve malnutrition problems.  相似文献   
7.
Journal of Crop Science and Biotechnology - A field experiment was conducted to identify drought tolerant, high yielding and stable tef genotypes using drought tolerance indices. Sixty-four tef...  相似文献   
8.
ABSTRACT

The aim of the present study was to evaluate the quality of wheat flour noodles supplemented with 0%, 10%, 20% and 30% grass carp protein concentrate (GCPC). Proximate composition, color analyses, cooking properties (cooking time, cooking loss, swelling index and water absorption index), texture profile analyses (TPA), and sensory evaluations were performed. Significant (p ≤ 0.05) increases in the crude protein (18.94–35.19%), crude fat (0.88–1.06%), and ash (0.89–1.02%) were recorded for GCPC supplemented cooked noodles. Brightness (L*), redness (a*) and yellowness (b*) of GCPC 10–30% fortified cooked noodles was recorded as 77.00–69.97, 1.50–2.81 and 19.08–22.25, respectively. Cooking loss (CL) and optimal cooking time were significantly (p ≤ 0.05) increased with increased level of GCPC from 0%-30%, with readings of 6.13% ?8.90% and 7.53–11.77 min, respectively. Swelling and water absorption indices showed a decreasing trend at 2.33–1.77 and 102.6–78.49%, respectively. A significant (p ≤ 0.05) decreasing trend in hardness (24.50–19.03N) was observed for cooked noodles with increased level of GCPC, while the remaining TPA parameters were significantly different at p> .05. Sensory analyses showed higher preference for control noodles and noodles fortified with 10% GCPC.  相似文献   
9.
Current agricultural practices and their impacts on the sustainability of crop production can be evaluated by simple and reliable soil structure assessment tools. The study was conducted to determine the effects of long-term (2006–2017) tillage systems on structural quality of a clayey soil using the visual evaluation of soil structure (VESS) and classical field and laboratory measurements. A field experiment with seven tillage systems, representing both traditional and conservation tillage methods, was conducted on a clayey soil in the Cukurova region, Turkey. Soil samples from 0–10, 10–20 and 20–25 cm depths were analysed for mean weight diameter (MWD), porosity and organic carbon. Penetration resistance (PR) was determined in each treatment plot. The VESS scores (<2) of upper 0–5 cm indicated a good structural quality for all tillage systems. The VESS scores were positively related to PR and MWD and negatively to macroporosity (MaP) and total porosity. In reduced and no-till systems, poorer soil structures were observed in subsurface layers where firm platy and angular blocky structures were defined. Mean VESS score (3.29) in 20–25 cm depth where PR was 3.01 MPa under no-till indicated a deterioration of soil structural quality; thus, immediate physical interventions would be needed. Lower VESS scores and PR values under strategic tillage which was created by ploughing half of no-till plots in November 2015 indicated successful correction of compaction caused by long-term no-till. The results suggest that the VESS approach is sensitive and useful in distinguishing compacted layers within the topsoil.  相似文献   
10.
Thirty samples of grassland surface soil, which had a diverse management history and consequently displayed a wide range of soil properties, were studied to analyze the relationships between soil microbial activity and soil properties. The microbial measurements included the number of bacteria, number of Gram negative bacteria, number of fungi obtained by the plate method, TTC reducing activity and nitrifying activity. In the uppermost layers (at the 0 to 2 cm depth), Simple correlation analyses showed that bacterial numbers were positively correlated with soil pH and negatively correlated with Bray No. 2 P, total C, and grassland age. TTC reducing activity and nitrifying activity were also positively correlated with soil pH, while the fungal number was not significantly related to any soil properties. In the lower layer (at the 5 to 15 cm depth), all of the microbial measurements were negatively correlated with grassland age and were positively correlated with microbial substrate level. soil pH and exchangeable K were positively correlated with the microbial measurements except for the Gram negative bacteria, and significant correlations among almost all the microbial measurements were observed. These results suggest that soli pH accounted primarily for microbial activities in the uppermost layers. Also microbial substrate level, soil pH and probably amounts of exchangeable K, which inevitably decreased with grassland age, appeared to control the microbial activities in the lower soil layers.  相似文献   
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