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51.
Undifferentiated acute calf diarrhoea is a major concern for the dairy industry and its aetiopathogenesis remains diverse. The present study aimed to examine the role of oxidative stress through estimation of erythrocyte lipid peroxide levels and blood zinc and copper concentrations using natural cases of diarrhoea in calves aged 15–30 days old. The calves were kept under identical managemental conditions and were provided with pooled whole colostrum during the first three days and thereafter with only whole milk until they were 1 month old. Diarrhoeic (n = 11) and normal calves (n = 11) of the same age group (15–30 days old) were randomly selected from an organized dairy farm for the study. The mean blood zinc concentration (50.01±2.45 μmol/L vs 66.06±3.06 μmol/L) was significantly (p < 0.05) lower and copper concentration was significantly (p < 0.05) higher in diarrhoeic calves (12.90±0.31 μmol/L vs. 9.44±0.16 μmol/L) than in the healthy calves. The erythrocyte lipid peroxides level was higher (p < 0.05) in diarrhoeic calves (6.88±0.23 nmol malondialdehyde (MDA) per mg of haemoglobin (Hb)) than healthy calves (6.27±0.07 nmol MDA per mg Hb). From the results of the study it is concluded that oxidative stress and antioxidant minerals (zinc and copper) might play important roles in the aetiopathogenesis of bovine calf diarrhoea.  相似文献   
52.
A 60-day feeding trial was conducted to study the effect of exogenous enzymes (xylanase and phytase) supplementation in the non-fermented and fermented de-oiled rice bran (DORB)-based diet of Labeo rohita. Four test diets (T1-DORB-based diet, T2-fermented DORB-based diet, T3-phytase and xylanase supplemented DORB-based diet, and T4-phytase and xylanase supplemented fermented DORB-based diet) were formulated and fed to the respective groups. Test diets T3 and T4 were supplemented with 0.01% xylanase (16,000 U kg?1) and 0.01% phytase (500 U kg?1) enzymes. One hundred twenty juveniles of L. rohita, with an average weight 5.01?±?0.02 g, were stocked in 12 uniform size plastic rectangular tanks in triplicate with 10 fishes per tank following a completely randomized design (CRD). Exogenous enzyme supplementation to the T3 group significantly improved the growth performance of L. rohita (p?<?0.05). Fermented DORB fed groups registered significantly lower growth irrespective of the supplementation of exogenous enzymes. The carcass composition (except CP %), enzyme activities (except amylase activity), globulin, and A/G ratio did not vary significantly (p?>?0.05). Based on the results of the present study, it is concluded that exogenous enzyme supplementation significantly increases the growth of fish fed with DORB-based diet.  相似文献   
53.
1.?The effects of injecting threonine in ovo on early growth, some immunological responses and the activity of digestive enzymes of broiler chicks were investigated. Fertile eggs were distributed into 6 groups, each of 60. These were: untreated control, sham control, 10, 20, 30 or 40 mg threonine. Threonine was dissolved in 0·5 ml sterile saline and inoculated into the yolk sac of the 14-d-old embryo through the narrow end of the egg.

2.?The ratio of chick to egg weight was 1·6% higher in the group given 30 mg threonine and at 28 d of age chicks receiving threonine were 29 to 79 g heavier than untreated controls.

3.?Food conversion ratio until 7 d after hatching was improved in those chicks receiving 10, 20 or 40 mg threonine but there was no significant effect on the activities of amylase, pepsin or trypsin.

4.?The humoral response to sheep red blood cells was significantly greater in those groups receiving 10, 20 or 30 mg threonine supplementation than in untreated controls.

5.?The response to phytohaemagglutinin-P, a measure of the cell-mediated immune response, was not affected, however.

6.?It is concluded that injections of 20 to 30 mg threonine into yolk sac can improve post-hatching growth and humoral responses of broiler chicks.  相似文献   

54.
Status of certain oxidative stress indices and zinc and copper concentrations in blood were estimated in dogs with localized demodicosis (LD) and generalized demodicosis (GD). In comparison to healthy control, erythrocytic lipid peroxides level and superoxide dismutase activity were significantly (P < 0.01) higher in both LD as well as GD. However, level of reduced glutathione and activity of catalase were significantly (P < 0.01) lower in both LD and GD. Blood zinc and copper levels in dogs with LD and GD were significantly (P < 0.01) lower than healthy control. Significant (P < 0.01) differences were also observed in different oxidative stress indices and zinc and copper levels in between LD and GD groups. From the present study, it was concluded that demodicosis is associated with oxidative stress and antioxidant supplementation may be beneficial in management of canine demodicosis.  相似文献   
55.
The present study was aimed to examine the status of antioxidants in water buffaloes with sarcoptic mange. Sixty-three buffaloes were divided into three groups, healthy control (group I, n=19), subclinical sarcoptic mange (group II, n=22) and clinical sarcoptic mange (group III, n=22). Lipid peroxides (LPO), superoxide dismutase (SOD), catalase (CAT), zinc and copper in hepatic tissues and serum alpha-tocopherol concentrations were measured. In comparison to group I, LPO was significantly (P<0.05) higher, while SOD and CAT were significantly (P<0.05) lower in group III. LPO and SOD activities were comparable between group I and II, but CAT was significantly (P<0.05) lower in group II. In group III, zinc, copper and alpha-tocopherol concentrations were significantly (P<0.05) lower than group I. Decrease in antioxidant enzyme activities and trace mineral concentrations suggested that sarcoptic mange in buffaloes is associated with compromise in antioxidant defense and oxidative stress may play important role in pathogenesis.  相似文献   
56.
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58.
Nutrients play an important role in improving productivity and quality of banana. It has been observed that the nutrient applied alone was less effective in improving banana production as compared to nutrients applied in combination with organic manures and biofertilizers. Keeping in view the conservation of soil health and quality production on a long-term basis, a field experiment was conducted during 2009–2011 to find out the influence of Integrated Nutrient Management of banana on leaf characteristics, growth and nutrient status of tissue cultured banana cv. ‘Grand Naine’. The study indicates that combination of inorganic fertilizers with organic manures, biofertilizers and bioagents significantly increased growth parameters, leaf characteristics, and leaf nutrient status of banana. The leaf characteristics in terms of functional leaves, total number of leaves, phyllochron, leaf area, and leaf area index were significantly influenced by the combination of inorganic fertilizers with different biofertilizers and organic manures. Similarly, leaf nutrient status like nitrogen, phosphorus pentoxide, (P2O5), potassium dioxide (K2O), and leaf relative water content were also influenced greatly by different nutrients. Treatment involving combination of 100% recommended dose of fertilizer (RDF) + arbuscular mycorrhizal fungi (AMF) + Azospirillum+ Trichoderma harzianum showed overall superiority in most of the parameters.  相似文献   
59.

De-oiled rice bran (DORB) is obtained after oil is removed from the rice bran. This is the commonly used ingredient in the feeding of Indian major carps due to its cheaper cost. DORB is used as a feed ingredient in cattle, poultry, and fish diet. Along with this, they are also used in making fiber-rich biscuits and extraction of an antioxidant compound like oryzanol and other industrial uses. Due to the increased competition, there will be a huge imbalance in the demand and supply for this ingredient in the years to come. DORB is associated with high fiber content, anti-nutrients, and non-starch polysaccharides which lead to its poor utilization resulting in a higher feed conversion ratio (FCR) in fish. Hence, the strategic utilization of this ingredient by solid-state fermentation, exogenous enzyme supplementation, and supplementing it with deficient nutrients like amino acids and fatty acids will help in improving the utilization of this ingredient.

  相似文献   
60.

Purpose

The balance of micronutrients in soils is important in nutrient use efficiency, environmental protection and the sustainability of agro-ecological systems. The deficiency or excess of micronutrients in the plough layer may decrease crop yield and/or quality. Therefore, it is essential to maintain appropriate levels of micronutrients in soil, not only for satisfying plant needs in order to sustain agricultural production but also for preventing any potential build-up of certain nutrients.

Materials and methods

A long-term fertilizer experiment started in 1969 at Central Rice Research Institute, Cuttack, Odisha, India. Using this experiment, a study was conducted to analyze the balance of micronutrients and their interrelationship. The experiment was composed of ten nutrient management treatments viz. control; nitrogen (N); N + phosphorus (NP); N + potassium (NK); nitrogen, phosphorus and potassium (NPK); farmyard manure (FYM); N + FYM; NP + FYM; NK + FYM; and NPK + FYM with three replications. Micronutrients in soil (total and available), added fertilizers and organic manures and in rice plant were analyzed. Besides, atmospheric deposition of the micronutrients to the experimental site was also calculated. A micronutrient balance sheet was prepared by the difference between output and input of total micronutrients.

Results and discussion

Application of FYM alone or in combination with chemical fertilizer increased the diethylenetriamine pentaacetate (DTPA)-extractable Fe, Mn and Zn over the control treatment. The treatment with NPK + FYM had the highest soil DTPA-extractable Fe, Mn, Zn and Cu after 41 years of cropping and fertilization. Application of chemical fertilizers without P decreased the DTPA-extractable Zn over the control while the inclusion of P in the fertilizer treatments maintained it on a par with the control. The application of P fertilizer and FYM either alone or in combination significantly increased the contents of total Fe, Mn, Zn and Cu in soil mainly due to their micronutrient content and atmospheric depositions. A negative balance of Zn was observed in the N, NP, NK and NPK treatments, while a positive balance observed in the remaining treatments. The balance of Mn was negative in all the treatments, due to higher uptake by the rice crop than its addition.

Conclusions

Long-term application of chemical fertilizers together with FYM maintained the availability of micronutrients in soil and, thus, their uptake by rice crop.
  相似文献   
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