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151.
152.
Livestock production is an integral part of the rain-fed and irrigated agriculture system in Pakistan. Animal production is
closely interlinked with the cropping systems and play a crucial role in the rural economy. Participatory rural appraisals
and economic opportunity surveys were conducted in two ecological zones (irrigated and rain-fed) and two dairy production
systems (peri-urban and mixed livestock). Major constraints in animal health, nutrition and reproduction were identified and
interventions were suggested to overcome these difficulties. The economic opportunity survey revealed that maximum opportunity
to enhance farmers’ income is to increase milk production per day per animal, which can be accomplished through coordinated
improvements in nutrition, reproduction and genetics. 相似文献
153.
Effect of Gibberellic Acid Spray during Ontogeny of Mustard on Growth, Nutrient Uptake and Yield Characteristics 总被引:2,自引:0,他引:2
In a field trial conducted during 1993–1994, mustard ( Brassica juncea L. Czern & Coss.) cv. Varuna was sprayed with either deionised water or 10−5 M GA3 at 40 (vegetative stage), 60 (flowering stage) or 80 (pod fill stage) days after sowing (DAS) to select the suitable growth stage for spray for augmenting productivity of the crop. Shoot length per plant, leaf number per plant, leaf area per plant, dry weight per plant and leaf area index and accumulation of N, P and K were recorded at 100 DAS. Pods per plant, seeds per pod, 1000 seed weight, seed yield, biological yield, harvest index and seed yield merit were computed at harvest. Growth, NPK accumulation and yield were maximal when spraying was done at 40 DAS. However, spraying at 40 and 60 DAS gave at par values for most of the growth and yield parameters. It was also noted that there was a significant difference in spray treatment at different growth stages only when G A, was sprayed and not when water was sprayed. 相似文献
154.
Gluten proteins from two cultivars of hard red spring (HRS) wheat with good and poor breadmaking quality were fractionated into 13 fractions by sequential extraction with dilute hydrochloric acid. Each subfraction was characterized by multistacking (MS) SDS‐PAGE under nonreducing conditions, followed by imaging densitometry. The glutenin polymers from the origins of MS‐SDS‐PAGE were analyzed by SDSP‐PAGE under reducing conditions to determine the composition of high and low molecular weight subunits. The results showed that fractions differed significantly in glutenin‐to‐gliadin ratios and in the size distribution of glutenin polymers. The earlier precipitated fractions were composed of more gliadins but fewer glutenin polymers. However, the glutenin polymers gradually increased in their relative quantities with the residue having the largest glutenin‐to‐gliadin ratio. The size distribution of glutenin polymers differed significantly from early precipitated to later fractions. The relative quantities of glutenin aggregates at the 4% origins increased significantly. The ratio of high molecular weight (HMW) to low molecular weight (LMW) glutenin subunits increased significantly from early to intermediate fractions. Between the two cultivars, significant differences were found in the ratio of HMW to LMW glutenin subunits and quantity of SDS insoluble glutenin polymers in the residue fraction with the better breadmaking quality cultivar ND706 having a greater ratio than the cultivar Sharp. It was concluded that the size distribution of glutenin polymers played an important role in determining the differences in breadmaking quality between the good and poor HRS wheat cultivars. 相似文献
155.
Singh D. Sanyal P.K. Swarnkar C.P. Khan F.A. Bhagwan P.S.K. 《Veterinary research communications》1999,23(4):229-240
The influence of the quality and quantity of diets on the disposition kinetics of albendazole were studied in sheep in two different experiments. The plasma concentration profiles of albendazole sulphoxide and albendazole sulphone were measured following intraruminal administration of albendazole at 5.0 mg/kg body weight in weaner sheep offered three different diets: 100% green Sorghum spp., 100% dry mature Cenchrus ciliaris hay and a 50:50 mix of these two diets. The peak plasma concentrations and the availability of the albendazole metabolites, as measured by the area under the concentration–time curve, were significantly higher (p<0.01) in the animals offered exclusively dry fodder compared to other diets. Changing the diet from dry to green fodder resulted in a significantly lower systemic availability of the drug metabolites. It is suggested that a decreased transit time of the digesta in the bowel on the green diet, with its high water content, limited the systemic availability of the drug by reducing the time available for gastrointestinal absorption.An experiment on the influence of different levels of pretreatment fasting on the pharmacokinetics of albendazole revealed significantly higher (p<0.05) plasma concentrations of the anthelmintically active sulphoxide metabolite from 12 h onwards following administration of the drug in animals subjected to 24 h of pretreatment fasting compared to other groups with pretreatment fasting of 8, 12 or 18 h. The area under the concentration–time curve and the minimum residence time of the drug metabolites were significantly greater (p<0.05) in animals that had been fasted for 24 h. It is suggested that fasting induces a decrease in the flow of digesta through the gastrointestinal tract of ruminants and prolongs the duration of dissolution of the drug, resulting in enhancement of the absorption of albendazole and of the systemic availability of its metabolites. 相似文献
156.
Many predatory arthropods occur naturally in turfgrass, and they provide adequate control of lepidopteran pests, such as fall armyworm, Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), and black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae). Recording predation is challenging under field conditions because predators rarely leave any evidence. Clay models were successfully employed for studying predation, and this technique is underutilized in turfgrass. Little is known about whether the characteristics of clay models, such as color, shape, and size, influence arthropod interactions in turfgrass. To improve the utility of clay models in turfgrass, the influence of the color, shape, and size of clay models on arthropod interactions was studied by exposing clay models during daytime and nighttime in a turfgrass field. The results showed that arthropods interacted with clay models, and various types of impressions were recorded, including paired marks, scratches, cuts, and pricks. Although the color of the clay model had no significant effects on arthropod interactions during the night, significantly greater numbers of impressions were noticed on the blue and green models than on the yellow models during the daytime. The caterpillar-shaped models captured significantly greater densities of impressions than the beetle-shaped models. Additionally, the number of impressions significantly increased with an increase in the size of the model regardless of shape. 相似文献
157.
The use of capillary electrophoresis in SDS (SDS‐CE) for separation and quantification of HMW glutenin subunits (HMW‐GS) was investigated. HMW‐GS were precipitated with 40% acetone from 50% 1‐propanol extract of flour under reducing conditions after removal of monomeric proteins with 50% 1‐propanol. Poly (ethylene oxide) was used in the running buffer (3% w/v) for SDS‐CE. The results indicated that HMW‐GS could be well separated by SDS‐CE, including subunits 7+8, 7+9, 2+12, 5+10, and 17+18. However, HMW‐GS showed delayed migration times compared with molecular weight protein standards. Some HMW‐GS were reversed in their mobilities in SDS‐CE compared with their mobility and molecular weights by SDS‐PAGE. Therefore, the SDS‐CE was unsuitable for MW determination of HMW‐GS. A linear response was obtained from SDS‐CE of a plot of the concentration of HMW‐GS of the 40% acetone precipitate versus corrected areas for absorbance at 214 nm. Quantification of HMW‐GS for the two biotypes (subunits 5+10 vs. 2+12) of an Australian wheat cultivar Warigal confirmed the differences between the two biotypes in their quantity of HMW‐GS. Therefore, the technique could be used to quantify HMW‐GS in conjunction with SDS‐PAGE. 相似文献
158.
Dietary copper requirement of Heteropneustes fossilis (6.74 ± 0.03 g) was determined by feeding purified diets containing same protein (400 g/kg) and gross energy (17.89 kJ/g) but different levels of copper for 12 weeks. Graded amount of CuSO4.5H2O (0, 1.96, 3.93, 5.89, 7.86, 9.82, 11.79 mg/kg) was supplemented to basal diet to attain desired dietary copper levels (0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mg/kg). Analysed dietary copper concentrations were 4.28, 4.63, 5.28, 5.70, 6.19 and 6.69 mg/kg. Absolute weight gain, feed conversion ratio and protein gain improved with the increasing levels of dietary copper up to 5.28 mg/kg. Further inclusion of copper at a level of 5.70 mg/kg did not improve the above parameters. Significantly higher (p < .05) plasma ceruloplasmin, liver copper‐zinc superoxide dismutase, catalase activities and lower thiobarbituric acid reactive substances were evident in fish receiving diets with 5.28 and 5.70 mg/kg copper compared to other groups. Whole body and liver copper concentrations increased significantly (p < .05) with increasing dietary copper levels. Quadratic regression analysis of absolute weight gain, feed conversion ratio, protein gain and broken‐line regression analysis of plasma ceruloplasmin activity and liver TBARS value against the variable dietary copper levels depicted the dietary copper requirements for fingerling H. fossilis in the range of 5.24–5.68 mg/kg. 相似文献
159.
Mohammad Redwanur Rahman Md. Asaduzzaman Md. Mahiuddin Zahangir SM Rashadul Islam Sk Ahmad‐Al Nahid Durin Akter Jahan Yahia Mahmud Mohammed Nurul Absar Khan 《Aquaculture Research》2020,51(6):2555-2572
Soft‐shell crab, a newly moulted crab having non‐calcified and hydrated soft exoskeleton, farming has been increasing tremendously in recent years throughout the world due to its high market price and consumer preferences. However, high aggressiveness and cannibalistic behaviour of mud crab limit its culture to an individual chamber system which ultimately makes the soft‐shell mud crab farming space and labour‐intensive. Therefore, the aim of this study was to improve the efficiency of soft‐shell crab production by autotomy of the claw and/or walking legs to reduce the moulting duration and intensify the culture system through double stocking in the existing individual chamber culture system. To achieve our objectives, a series of experiment were conducted at both indoor and on‐farm levels by removing the claw and/or walking legs of Scylla olivacea for two consecutive moulting cycles. Results showed that both claw ablation significantly (p < .01) shortened the moulting duration and increased the carapace width, weight gain, specific growth rate, feeding efficiency and yield parameter compared to the non‐ablated crabs more prominently at 1st moulting than the 2nd moulting in both indoor and on‐farm trials. Ablation of all walking legs while keeping the claw intact did not significantly influence (p > .05) the moulting duration and carapace width, but significantly (p < .01) improved the specific growth rate, weight gain, feeding efficiency and yield parameters at 1st moulting compared to the non‐ablation and unilateral three walking leg ablation groups. However, ablation of all appendages (both claw and walking legs) showed significant (p < .01) improvements of carapace width, weight gain, specific growth rate, feeding efficiency and yield parameters, and shortened the moulting duration up to 23 days from 34 days during 1st moulting and up to 27 days from 40 days at 2nd moulting. The survivals of different autotomized mud crabs were statistically non‐significant (p > .05) to the non‐autotomized crabs in various indoor and on‐farm trials. Besides improving the production performances, ablation of bilateral claw and all appendages allowed to double the stocking density in the existing individual chamber‐based soft‐shell crab farming that enhanced the production about threefold higher than the existing individual chamber‐based culture system. Finally, our results suggest that autotomy could be a promising technology for the commercial farming of soft‐shell mud crab in near future. 相似文献
160.
Disadvantages of frozen doughs are their variable performance and loss of stability over long‐term frozen storage. Changes in rheological properties of frozen doughs have been reported to be due to the physical damage of the gluten network caused by ice crystallization and recrystallization. The objective of this study was to determine the effect of hydrophilic gums on ice crystallization and recrystallization for improvement of the shelf‐life stability of frozen dough. The present research involved use of the Hard Red Spring wheat cultivar Grandin and hydrophilic gums such as carboxymethyl cellulose (CMC), gum arabic, kappa carrageenan (κ‐carrageenan), and locust bean gum at three different levels each on doughs stored frozen for up to 16 weeks. The dough characteristics were analyzed after day 0, day 1, and after 4, 8, 12, and 16 weeks of frozen storage using data from differential scanning calorimetry (DSC), water activity, extensigraph, and proof time. The ΔH value of freezable water endothermic transitions obtained using DSC increased with storage time for all treatments. However, addition of different levels of the four gums lowered the ΔH value, indicating a decrease in freezable water. Doughs with locust bean gum gave a higher peak force, measured using the Kieffer dough extensibility rig of the texture analyzer, and lower proof time, indicating better retention of baking quality. Maximum resistance to extension increased upon addition of 1 and 3%; CMC; 1 and 3%; κ‐carrageenan; and 1, 2, and 3% locust bean gum as compared with the control. The various periods of storage or gum treatments did not affect the water activity of the thawed frozen doughs. Doughs with locust bean gum gave significantly lower proof time compared with the other treatments and the control. CMC gave the second lowest values, followed by gum arabic treatment. Addition of κ‐carrageenan increased the proof time compared with the control. In summary, locust bean gum, gum arabic, and CMC improved the dough characteristics to varying degrees. κ‐Carrageenan was the only gum that showed a detrimental effect on frozen dough. 相似文献