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91.
Glycine betaine (GB) is an important organic compound mediating plant responses to environmental stresses. However, despite ample research on this biomolecule, the potential of GB in mitigating the effects of waterlogging in plants has not been established. Therefore, we studied the influence of GB on growth and physiology of tomato plants under waterlogged conditions. Waterlogging reduced plant growth, degraded chlorophyll, and increased concentration of malondialdehyde and hydrogen peroxide that deteriorated membrane integrity. Waterlogging increased catalase and peroxidase activities. Waterlogging increased the concentration of Na and reduced concentrations of K. Reductions in root Ca were also recorded. GB enhanced growth, concentration of chlorophyll and activities of superoxide dismutase, catalase, and peroxidase that in turn protected the plants from oxidative damage. GB decreased Na while increasing leaf and root K and stem and fruit Ca under waterlogging. Waterlogging reduced fruit quality. There was decrease in protein, fat, and total dissolved solids and an increase in fruit moisture, P, and Na in plants under waterlogging. GB enhanced fruit quality largely by improving fruit protein, ash, fat, TDS, and Ca, while it decreased fruit Na. The results of this study suggest the use of GB for commercial production of tomato where waterlogging is likely.  相似文献   
92.

The aim of this study was to determine the prevalence, serological diversity, and virulence of Dichelobacter nodosus in footrot lesions of sheep and identification of its predominant serotype as a potential vaccine candidate. The overall prevalence of footrot in sheep was 16.19%, and ranged from 13.69 to 19.71%, respectively. A total of 759 flocks with 22,698 sheep were investigated for footrot and 2374 clinical samples were collected from naturally infected sheep exhibiting footrot lesions. Of the 2374 samples collected, 1446 (60.90%) were positive for D. nodosus by polymerase chain reaction (PCR). These positive samples when subjected to serogroup-specific multiplex PCR, 1337 (92.46%) samples carried serogroup B, 247 (17.08%) possessed serogroup E, 86 (5.94%) serogroup I, and one (0.069%) serogroup G of D. nodosus. While mixed infection of serogroups B and E was detected in 127 (8.78%), B and I in 46 (3.18%) and B, E, and I in 26 (1.79%) samples, respectively. The serogroup B of D. nodosus was the predominant (92.47%) serogroup affecting sheep population with footrot followed by serogroup E (19.91%) and serogroup I (4.57%), respectively. Virulent status of D. nodosus strains were confirmed by presence of virulence-specific integrase A (intA) gene and the production of thermostable proteases. The intA gene was detected in 709 (72.79%) samples while gelatin gel test carried out on 246 representative isolates all positive for intA gene produced thermostable proteases, confirming their virulence nature. The PCR-restriction fragment length polymorphism (PCR-RFLP) of whole fimA gene of serogroup B revealed the predominance of serotype B5 (82.97%) of serogroup B. This information suggests that serotype B5 is the predominant serotype of D. nodosus associated with severe footrot lesions in sheep in Jammu & Kashmir (J&K), India. Hence, this serotype can be a potential vaccine candidate for the effective control and treatment of ovine footrot.

  相似文献   
93.
Zinc (Zn) deficiency is frequently observed in mangoes grown in calcareous soils. Inherent inability of mango to extract sufficient Zn from the soil exacerbates this situation. Therefore, mitigating effects of Zn application was investigated on flowering, fruit setting, yield and quality of mango cv. Samar Bahisht Chaunsa growing in calcareous soils. The experiment consisted of five treatments: control—no Zn, soil application of 50 and 100 g ZnSO4 per tree and foliar application of 0.5? and 1.0?% ZnSO4 solution. Zn was applied twice in the 2nd week of November, 2011 and 3rd week of March, 2012, respectively. The experiment was repeated on the same dates during the next growing season. Zn application significantly increased number of flower panicle, fruits matured panicle, leaf Zn concentrations, fruit size, peel thickness, fruit weights at harvest and after ripening and fruit yield tree, whereas it reduced malformed panicles and early fruit drop. However, flower sex ratio and fruit set remained statistically unaffected. Similarly, fruit quality in terms of total soluble solids, flesh color, aroma, flavor and overall acceptability significantly improved as compared to control. Foliar application mitigated Zn deficiency more effectively than the soil application in calcareous soils.  相似文献   
94.
1. The effect of including Leucaena (Leucaena leucocephala) leaf meal (LLM) in broiler diets was investigated employing LLM at 0, 50, 100, 150 and 200 g/kg diet. Experiments were also conducted to investigate whether reduced food intake of diets containing LLM is responsible for the growth depression.

2. LLM appears to be a good source of protein and calcium.

3. Food intake was not significantly affected (P>0.05) with dietary LLM inclusion up to 200 g/kg.

4. Inclusion of LLM up to 150 g/kg diet did not influence significantly (P>0.05) the performance of broilers in terms of body weight gain and food efficiency. However, inclusion of LLM at 200 g/kg diet had an adverse effect on weight gain and food efficiency, when compared to other dietary treatments. The profitability over food costs was low with the 200 g LLM/kg diet compared to those of other diets.

5. It may be inferred from these experiments that LLM can safely be included in broiler diets up to 150 g/kg.

6. Studies using force‐feeding and restricted feeding techniques indicated that reduced food intake was not responsible for the growth depression in diets containing higher amounts of LLM.  相似文献   

95.
This study investigated the influence of Bacillus‐based probiotics on performance and intestinal health in broiler challenged with Clostridium perfringens‐induced necrotic enteritis. One‐day‐old Arbor Acre (n = 480) were randomly assigned to four treatments with 10 cages of 12 birds: (a) basal diet negative control (NC), with no probiotics nor antibiotics formulated to contain 2,930 and 3,060 kcal/kg with 24.07 and 15.98% CP, for starter and finisher diet, respectively, (b) basal diet + enramycin (5 mg/kg), an antibiotic growth promoter (AGP); (c) basal diet + Bacillus subtilis B21 at 2 × 109 CFU per g (BS); (d) basal diet + Bacillus licheniformis B26 at 2 × 109 CFU per g (BL); growth performance, intestinal morphology, intestinal lesion scores, short‐chain fatty acids (SCFAs) and mucosal barrier tight junction's (TJ) mRNA expression were assessed. NC‐ and BL‐fed groups showed higher (p = 0.005) average daily feed intake from d1 to d21 than AGP and BS, whereas BS‐ and AGP‐fed groups showed higher average daily weight gain from d22 to d42 and d1 to d42 of age. Higher mortality rate of (12.5%) and lower of (5.5%) were recorded in AGP and NC fed‐groups respectively, lesion score was higher in BS and BL than in AGP, while no lesion was observed in NC group, results revealed higher duodenum and jejunum villus height to crypt depth (VH:CD) compared with NC and BS. Probiotics‐fed groups showed higher total (SCFAs), acetic and butyric acid concentrations at d21 post‐challenge (PC) than other groups. The expression of claudin‐1 was upregulated in duodenum (d7) PC and in jejunum (d7) and (d21) PC in BL group, while at d21 PC, the expression of occludens was higher in jejunum and ileum by AGP and BL. The present study indicated both BS and BL have some similarity with AGP in preventing or partially preventing NE effect in broilers.  相似文献   
96.
Foot and mouth disease (FMD) remains subclinical and self-limiting in small ruminants, but risk of spread of infection to susceptible cohorts is of great epidemiological significance; therefore, small ruminants must be included in vaccination campaigns in FMD endemic regions. Three groups of goats already immunized against peste des petits ruminants (PPR) were vaccinated with FMD and PPR vaccines alone or concurrently. The specific antibody response against three FMD virus strains and PPR virus were evaluated by competitive enzyme-linked immunosorbent assay (cELISA). Goats concurrently vaccinated with PPR + FMD vaccines had significantly (p < 0.05) higher antibody titers to two serotypes of FMD virus at 28, 45, and 60 days post-immunization compared to goats vaccinated with FMD vaccine alone, while goats vaccinated with PPR vaccines alone or PPR + FMD vaccines concurrently showed similar antibody kinetics against PPR virus up till 60 days post-vaccination. Overall, antibody kinetic curves for all three tested strains of FMD virus and PPR virus were similar in vaccinated groups during the course of experiment.  相似文献   
97.
Photosensitization is severe dermatitis or oxidative/chemical changes in the epidermal tissues activated by the light-induced excitation of molecules within the tissue. It is a series of reactions mediated through light receptors and is more common when the plant-produced metabolites are heterocyclic/polyphenols in nature. The areas affected are exposed body parts and mostly non-pigmented areas with least ultraviolet protection. Similarly, cellular alteration also occurs in the affected animal’s dermal tissues and body parts and grazing animals by the accumulation and activation of photodynamic molecules. Photo-oxidation can also occur within the plant due to the generation of reactive oxygen species causing damage and degradation in the form of free radicals and DNA. During the last few decades, many new tropical grass species have been introduced in the grazing lands which are genetically modified, and the animals grazing on them are facing various forms of toxicity including photosensitization. The plant’s secondary metabolites/drugs may cause toxicity when bacteria, viral agents, fungi (Pithomyces chartarum), or neoplasia injures the liver and prevents the phylloerythrin excretion. All these may disturb the liver enzymes and blood profile causing a decrease in weight and production (wool and milk etc.) with severe dermal, digestive, and nervous problems. Recent advancements in OMICS (cellomics, ethomics, metabolomics, metabonomics, and glycomics) have enabled us to detect and identify the plants’ secondary metabolites and changes in the animal’s physiology and histopathology as a causative of photosensitivity. The review focuses on types of photosensitization, reasons, secondary metabolic compounds, chemistry, and environmental effect on plants.  相似文献   
98.
Alpha‐lipoic acid (ALA) is a multifunction antioxidant that is produced in small amount by cells as well as its dietary provision facilitates fatty acid mobilization, energy expenditure as well as can scavenge free radicals in poultry birds. It exists in oxidized as well as reduced form, characterized by growth promoting, anti‐inflammatory, antioxidative, immunostimulatory, and hypocholesterolemic properties when fed as dietary supplement to farm animals particularly chicken birds. Recently, several studies reported that dietary supplementation of ALA can influence growth performance indicators, immunological, biochemical characteristics, lipid metabolism, and oxidative stress as well as increase antioxidant potential and storability of poultry meat and meat products. Accordingly, this paper adds the reviews and discusses the outcomes of studies documenting the effect of lipoic acid dietary fortification on growth performance, biochemical, and immunological characteristics as well as the effects on lipid peroxidation of fresh meat and meat‐based products. Furthermore, this paper also describes the possibilities of utilization of ALA as a feed additive in poultry nutrition to improve the growth performance of poultry as well as meat quality of resultant chicken birds.  相似文献   
99.
Plants respond to their external environment to optimize their nutrition and production potential to minimize the food security issues and support sustainable agriculture system. Phosphorus (P) is an important nutrient for plants and is involved in plant metabolic processes. It is mostly available as orthophosphate and has a tendency to form complexes with cations. It has low mobility in soil, thus becoming unavailable for plant uptake that causes a reduction in plant growth and yield. Besides free P, phytate is the major form of organic P in soil and plant tissues. Phytases obtained from different sources, that is, plants, animals, and microorganisms, catalyze the hydrolysis of phytate and release available forms of inorganic P. The knowledge of mechanisms involved in catalytic activity of phytase obtained from microorganisms in soil is limited. This review summarizes the role of microbial phytase in releasing organic P by hydrolysis of phytate and factors affecting its activity in the soil.  相似文献   
100.
Limited water availability hampers the sustainability of crop production. Exogenous application of glycinebetaine (GB) and salicylic acid (SA) has been found very effective in reducing the adverse effects of water scarcity. This study was conducted to examine the possible role of exogenous GB and SA application in improving the growth and water relations of hybrid sunflower ( Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation, viz. control (normal irrigations), water stress at budding stage (irrigation missing at budding stage) and water stress at flowering stage (FS) (irrigation missing at FS). GB and SA were applied exogenously at 100 and 0.724 m m respectively, each at the budding and FS. Control plants did not receive application of GB and SA. Water stress reduced the leaf area index (LAI), leaf area duration (LAD), crop growth rate (CGR), leaf relative water contents, water potential, osmotic potential, turgor pressure, achene yield and water use efficiency. Nevertheless, exogenous GB and SA application appreciably improved these attributes under water stress. However, exogenous GB application at the FS was more effective than other treatments. Net assimilation rate was not affected by water stress as well as application of GB and SA. The protein contents were considerably increased by water stress at different growth stages, but were reduced by exogenous GB and SA application. The effects of water stress and foliar application of GB were more pronounced when applied at FS than at the budding stage. Moreover, exogenous GB application was only advantageous under stress conditions.  相似文献   
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