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101.
A study was undertaken to investigate the changes of plasma non-esterified fatty acids (NEFA), glucose and alpha-amino nitrogen and their relationship with age, body weight (BW) and plasma growth hormone (GH) in growing buffaloes. For the purpose, six growing female Murrah buffalo calves of 6-8 months of age were selected on the basis of their BW and fed according to Kearl standard (Nutrient Requirements of Ruminants in Developing Countries, International Feedstuffs Institute, Utah State University, Utah, USA, 1982, p. 89) for growing buffaloes (target growth rate 500 g/day) to meet energy and protein requirement of the animals. Blood samples collected at fortnight intervals for 1 year were analysed for plasma NEFA, glucose, alpha-amino nitrogen and GH. The animals were also weighed at fortnight intervals. Plasma NEFA and glucose levels were found to decrease (p < 0.01) with age. Unlike plasma NEFA and glucose, plasma alpha-amino nitrogen level increased (p < 0.01) as the buffaloes become older. Plasma NEFA and glucose concentrations in growing buffaloes were found to be positively correlated with plasma GH (r = 0.379 and 0.420 respectively), but these were non-significant (p > 0.01). However, plasma NEFA and glucose showed a good correlation (p < 0.01; r = 0.780 and 0.652 respectively) with plasma GH per 100 kg live weight. Plasma alpha-amino nitrogen exhibited non-significant (p > 0.01) negative correlation (r = -0.295) with plasma GH but a negative correlation (p < 0.01; r = -0.641) with GH per 100 kg BW. So, plasma metabolites showed a definite pattern of change during growth and these have a significant (p < 0.01) correlation with plasma GH per 100 kg BW than GH.  相似文献   
102.
Malted cereals are rich sources of alpha-amylase, which catalyzes the random hydrolysis of internal alpha-(1-4)-glycosidic bonds of starch, leading to liquefaction. Amylases play a role in the predigestion of starch, leading to a reduction in the water absorption capacity of the cereal. Among the three cereal amylases (barley, ragi, and jowar), jowar amylase is found to be the most thermostable. The major amylase from malted jowar, a 47 kDa alpha-amylase, purified to homogeneity, is rich in beta structure ( approximately 60%) like other cereal amylases. T(m), the midpoint of thermal inactivation, is found to be 69.6 +/- 0.3 degrees C. Thermal inactivation is found to follow first-order kinetics at pH 4.8, the pH optimum of the enzyme. Activation energy, E(a), is found to be 45.3 +/- 0.2 kcal mol(-)(1). The activation enthalpy (DeltaH), entropy (DeltaS*), and free energy change (DeltaG) are calculated to be 44.6 +/- 0.2 kcal mol(-)(1), 57.1 +/- 0.3 cal mol(-)(1) K(-)(1), and 25.2 +/- 0.2 kcal mol(-)(1), respectively. The thermal stability of the enzyme in the presence of the commonly used food additives NaCl and sucrose has been studied. T(m) is found to decrease to 66.3 +/- 0.3, 58.1 +/- 0.2, and 48.1 +/- 0.5 degrees C, corresponding to the presence of 0.1, 0.5, and 1 M NaCl, respectively. Sucrose acts as a stabilizer; the T(m) value is found to be 77.3 +/- 0.3 degrees C compared to 69.6 +/- 0.3 degrees C in the control.  相似文献   
103.
Effects of long-term growth hormone-releasing factor (GRF) on growth performance, feed conversion efficiency (FCE) and dry matter intake (DMI) were studied in growing buffaloes. Twelve female Murrah buffaloes of 6-8 months of age were divided into two groups of six each on the basis of their body weights so that the average body weights of the groups did not differ (p > 0.05). Animals of each group were administered intravenously with either sterile distilled water (control group) or equal volume of GRF solution containing 10 mug GRF (1-44)-NH2/100 kg body weight (treatment group) at fortnight interval from week 6 (5-week pre-treatment period) for 36 weeks (weeks 6-42 treatment period). Thereafter a 10-week post-treatment period was added. All the animals were weighed consecutively 2 days in a week and the average body weight of the two observations in the week was thus considered for further calculation. Dry matter intake was recorded daily. Average daily gain, FCE and DMI/100 kg body weight were also calculated. Plasma progesterone was estimated in the samples collected twice a week at 3-4-day intervals to assess whether either group had begun ovarian cycles. It was found that ADG and FCE were higher (p < 0.01) in GRF-treated animals during treatment and even 10-week post-treatment period. Interestingly, total DMI was not different (p > 0.05) between the groups during treatment period but found to be lower in GRF treated animals during post-treatment period. The DMI/100 kg body weight was lower (p < 0.01) in GRF-treated animals during treatment and even after cessation of treatment for 10 weeks. The GRF administration for long-term increased (p < 0.05) plasma progesterone. Plasma progesterone concentrations suggest that no animal from either group reached puberty till the end of the experiment. In conclusion, repeated GRF administration for longer term decreased (p < 0.01) DMI/100 kg body weight and increased (p < 0.01) FCE and enabled the animals to grow faster.  相似文献   
104.
To investigate the effects of long-term growth hormone-releasing factor (GRF) administration on plasma growth hormone (GH), LH and progesterone and body weight gain in growing buffalo calves, 12 female Murrah buffaloes within the age group of 6-8 months of age were divided into two groups (treatment and control groups) of six each in such a way so that average body weights between the groups did not differ (p > 0.05). Control buffaloes were not given any hormonal treatment and treatment group buffaloes were treated with synthetic bovine GRF [bGRF (1-44)-NH(2)] at the rate of 10 microg/100 kg body weight intravenously at an interval of 15 days from week 6 (5-week pre-treatment period) till 18 injections were completed (week 6-42 treatment period) and thereafter, effect of exogenous GRF were observed for 10-week post-treatment period. Jugular blood samples were drawn twice a week at 3-4-day intervals for plasma GH, LH and progesterone quantification. Body weight of all animals was recorded twice a week. During pre-treatment period, mean plasma GH, LH and progesterone did not differ (p > 0.05) between the groups. But during treatment as well as post-treatment period, mean plasma GH levels were found to be significantly (p < 0.01) higher in treatment than control group of buffaloes. Administration of GRF for longer term sustained a higher level of plasma GH even after cessation of treatment. GRF-treated buffaloes attained higher (p < 0.01) body weight than the controls. Repeated GRF administration for long-term significantly (p < 0.01) increased plasma LH and progesterone. In conclusion, repeated long-term exogenous GRF administration induces and even enhances GH release without any sign of refractoriness. GRF may, therefore, be used to induce daily GH release without loss of responsiveness over an extended period of time in young growing female buffaloes and it may assist these animals to grow faster.  相似文献   
105.
Chlorpyrifos is an organophosphorus insecticide used to control insect pests in soil. The fate of chlorpyrifos in soils under different moisture regimes is of interest because application directions specify soil-surface treatments for a number of agricultural and urban pests. Chlorpyrifos was degraded rapidly in all air-dry soils and slightly more slowly in soils at field capacity and/or under submerged conditions. Degradation rates were influenced by clay-catalysed hydrolysis under air-dry conditions and neutral or alkaline hydrolysis under submerged conditions. Degradation was faster in Bellary soil (chromic haplustert) and slower in Chettalli soil (ustic palehumult) under all three moisture regimes. The calculated half-lives ranged from 1·6 to 10·0, 5·2 to 22·0 and 8·7 to 25·1 days under air-dry, field capacity and submergence respectively at an application rate of 10 mg kg-1. © 1997 SCI.  相似文献   
106.
Water, Air, &; Soil Pollution - Application of soluble forms of nitrogen (N) fertilizers to citrus trees in sandy soils of central Florida may cause leaching of NO 3 ? below the rooting...  相似文献   
107.
Several Indian snack foods consist of an outer coating made with a wheat flour batter and a sweet or savoury filling. In order to study the possibilities of improving the rheological characteristics of batters used in the batter-coated products, wheat flour was steamed for varying periods of time (5, 15 and 30 min). The studies indicated that SDS-sedimentation values decreased from 35 to 24·5 mL, gluten forming protein was completely denatured, gel mobility increased and solubility of gliadin in the β-region decreased with an increase in the steaming period.The steamed wheat flour was used to make batters having 30, 33 and 36% solids suspended in water. The apparent viscosities of the batter increased from 9·6 to 19·2 Pa·s; the yield stress increased from 5·3 to 7·15 Pa; the consistency index increased from 27·86 to 78·31 Pa·sn. The maximum values of all three parameters were observed in the batter which had a solids concentration of 36%, and which had been made with a flour steamed for 30 min. On the other hand, the flow behaviour index decreased slightly with duration of steaming and with increasing solid concentrations in the batter.  相似文献   
108.
Cowpea, Vigna unguiculata (L.), is an important grain legume grown in the tropics where it constitutes a valuable source of protein in the diets of millions of people. Some abiotic and biotic stresses adversely affect its productivity. A review of the genetics, genomics and breeding of cowpea is presented in this article. Cowpea breeding programmes have studied intensively qualitative and quantitative genetics of the crop to better enhance its improvement. A number of initiatives including Tropical Legumes projects have contributed to the development of cowpea genomic resources. Recent progress in the development of consensus genetic map containing 37,372 SNPs mapped to 3,280 bins will strengthen cowpea trait discovery pipeline. Several informative markers associated with quantitative trait loci (QTL) related to desirable attributes of cowpea were generated. Cowpea genetic improvement activities aim at the development of drought tolerant, phosphorus use efficient, bacterial blight and virus resistant lines through exploiting available genetic resources as well as deployment of modern breeding tools that will enhance genetic gain when grown by sub‐Saharan Africa farmers.  相似文献   
109.
Single blood samples from 106 pregnant and seven non-pregnant Karan Swiss cows and 104 pregnant and nine non-pregnant Murrah buffaloes were measured for oestrone and oestrone sulphate hormones by radioimmunoassay. Mean plasma oestrone level was below detection limit (less than 2.5 pg/ml) in non-pregnant and 1 month pregnant cows and buffaloes. In cows the mean oestrone level fluctuated narrowly between 10.25 and 26.65 pg/ml between the second and eight months of pregnancy, followed by a steep rise in the ninth and especially in the tenth month (151.24 pg/ml). In buffaloes mean oestrone concentrations were lower and fluctuated between 14.81 and 23.56 pg/ml during the second to ninth months of pregnancy, rising sharply in the tenth month to a peak of 47.37 pg/ml. Mean oestrone sulphate levels were below detection limit (less than 16 pg/ml) during non-pregnancy, first and second months of pregnancy in cows, increasing sharply thereafter to a peak of 6401.38 pg/ml in the tenth month of pregnancy. In buffaloes, low mean levels of oestrone sulphate were recorded in the non-pregnant and up to the fourth month of pregnancy with the levels rising sharply thereafter to a peak of 6559.82 pg/ml in the tenth month. The hormone levels were not significantly different in the two species (P greater than 0.01). The possibility of using oestrone sulphate measurement as a test of pregnancy confirmation has been indicated for both species.  相似文献   
110.
A method of estimating progesterone in buffalo whole milk by EIA using progesterone 6 beta-OH-hemisuccinate-horseradish peroxidase as the enzyme label and an antiserum raised against progesterone-7 alpha-carboxyethyl-thioether-BSA was developed. The microtitration plates used in the assay were first coated with affinity purified sheep IgG developed against rabbit IgG. The immune reaction was performed by incubating a mixture of 1 microliter of whole milk (diluted to 20 microliters with assay buffer), 100 microliters of enzyme label and 100 microliters of antiserum for 90 min in the dark. After washing the plates, 150 microliters of the substrate solution was added. The mixture was incubated in the dark for 40 min before the reaction was stopped and the optical density was measured at 450 nm. The calibration curve was sensitive in the range 0.8-40 pg/well, corresponding to 0.8-40 ng/ml. Milk samples from cycling buffaloes were tested for progesterone concentration by running parallel EIA and RIA. A good correlation of 0.91 was obtained and the estimated values were similar using both techniques. The method has demonstrated about 10 times greater sensitivity than RIA in buffalo milk.  相似文献   
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