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51.
Yatoo Mohd. Iqbal Parray Oveas Raffiq Mir Muheet Bhat Riyaz Ahmed Malik Hamid Ullah Fazili Mujeeb ur Rehman Qureshi Sabia Mir Masood Salim Yousuf Raja Wasim Tufani Noor Alam Dhama Kuldeep Bashir Shah Tauseef 《Tropical animal health and production》2019,51(8):2127-2137
Tropical Animal Health and Production - Therapeutic management of contagious caprine pleuroneumonia (CCPP) involves mostly the use of oxytetracycline followed by enrofloxacin and rarely tylosin. In... 相似文献
52.
53.
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
54.
Xiaoyun Zhou Khalid Abbas Mingyun Li Libao Fang Su Li Weimin Wang 《Aquaculture International》2010,18(3):349-359
To determine the cytotype with better traits for the aquaculture practices of the dojo loach Misgurnus anguillicaudatus from the viewpoint of fish farming improvement, factorial crosses (2n♀ × 2n♂, 2n♀ × 4n♂, 4n♀ × 2n♂, 4n♀ × 4n♂) were conducted
between natural diploids (D) and tetraploids (T), producing DD, DT, TD, and TT groups (female listed first). The potential
benefits of the different cytotypes in culture were evaluated by comparing growth performance and survival rate for a 15-month
rearing trial under the same production conditions. The average fertilization rate in DT and TT was significantly lower than
in the DD and TD groups, possibly indicating the poor fertilizing capacity of the tetraploid sires. Survival rate in DT and
TD was slightly lower than in DD but significantly higher than in the TT groups. Tetraploid females produced obviously larger
eggs than diploids and, subsequently, significantly longer initial body length of TT and TD than DD and DT fry. However, from
the second month of the growth trial, TT suffered higher mortality than other cytotypes, which significantly influenced morphometric
growth parameters. The TD group exhibited superior growth performance throughout the experiment. The mean body length of DT
was comparable with that of DD fish during the first 7 months but began to outgrow DD from the 9th month. This study suggests
that the relatively better growth of tetraploid and higher survival rate of diploid can be integrated via inter-ploidy hybridization
to get TD triploids with better culture traits. 相似文献
55.
Felipe Pierezan Khalid Shahin Taylor I. Heckman June Ang Barbara A. Byrne Esteban Soto 《Journal of fish diseases》2020,43(4):485-490
Outbreaks of an infectious disease affecting cultured white sturgeon (Acipenser transmontanus) were investigated. Clinical signs included erratic swimming, arching of the back and mortality. Necropsy findings included poorly demarcated yellow to dark-red and friable lesions in the epaxial muscle, ulcerative skin lesions and haemorrhages in the swim bladder and coelomic wall. Histological evaluation revealed areas of necrotizing and heterophilic myositis with aggregates of bacterial cocci. The lumen of blood vessels in the dermis, under ulcerated areas, and in the posterior kidney, was occluded by fibrin thrombi. Aggregates of Gram-positive cocci were observed in the muscle lesions and within the fibrin thrombi in the dermis and kidney. Genetically homogeneous Streptococcus iniae strains were recovered from affected fish from different outbreaks. The isolates shared high degree of similarity at gene locus (gyrB) with previously characterized S. iniae from cultured fish in California, confirming the emergence of this particular strain of S. iniae in US aquaculture. 相似文献
56.
Perspectives of Using L-Tryptophan for Improving Productivity of Agricultural Crops: A Review 总被引:1,自引:0,他引:1
Plant growth regulators are biologically active signaling molecules that regulate a number of plant physiological processes. Auxin (indole-3-acetic acid) is an important plant growth regulator and is synthesized within plant tissues through L-tryptophan (L-TRP)-dependent and -independent pathways. It has been found that plants respond to exogenously applied L-TRP due to insufficient endogenous auxin biosynthesis. The exogenous application of L-TRP is highly significant for normal plant growth and development. L-tryptophan is applied through foliar spray, seed priming, and soil application. Soil-applied L-TRP is either directly taken up by plants or metabolized to auxin by soil microbiota and then absorbed by plant roots. Similarly, foliar spray and seed priming with L-TRP stimulates auxin synthesis within plants and improves the growth and productivity of agricultural crops. Furthermore, L-TRP contains approximately 14% nitrogen (N) in its composition, which is released upon its metabolism within a plant or in the rhizosphere and plays a role in enhancing crop productivity. This review deals with assessing crop responses under the exogenous application of L-TRP in normal and stressed environments, mode of action of L-TRP, advantages of using L-TRP over other auxin precursors, and role of the simultaneous use of L-TRP and auxin-producing microbes in improving the productivity of agricultural crops. To the best of our knowledge, this is the first review reporting the importance of the use of L-TRP in agriculture. 相似文献
57.
Rana M. Sabir Tariq Khalid P. Akhtar Amjad Hameed Najeeb Ullah Muhammad Y. Saleem Imran ul Haq 《European journal of plant pathology / European Foundation for Plant Pathology》2018,150(4):911-922
Shoe-string disease caused by Cucumber mosaic virus (CMV) is one of the major threats to tomato production worldwide. The alteration in some biochemical parameters in leaves of the susceptible tomato genotype (Nagina) associated with CMV infection and the effect of exogenous application of salicylic acid (SA) and benzothiadiazole (BTH) were studied in this paper. Results showed that exogenous treatment with SA and BTH not only led to plants which gave significantly more yield than diseased controls (DC), but also delayed symptom expression and reduced disease severity. Analysis of biochemical parameters indicated that exogenous application of elicitors and viral infection, significantly affected the activity of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). Compared to the DC plants, minimum disease severity and maximum number of fruit were recorded after a single dose of SA + BTH. Maximum plant height was recorded after weekly application of SA and maximum fruit yield per plant was gained with single dose of SA. Moreover, the activity of POD was significantly elicited many-fold after weekly application of SA + BTH, while higher amount of SOD was recorded with single dose of SA. The activity of CAT was also significantly accelerated after weekly application of SA + BTH while increased level of APX was noticed with single dose of BTH. In conclusion, the combined application of SA and BTH played an important role in induction of defense mechanism against CMV infection and can be useful in tomato disease management programs. 相似文献
58.
Noureen Arshad Khalid Mahmood Zia Farukh Jabeen Muhammad Naveed Anjum Nadia Akram Muhammad Kaleem Khosa 《Fibers and Polymers》2018,19(11):2219-2228
The research work was carried out to synthesize a series of novel chitosan based water dispersible polyurethanes (CS-WDPUs). The three step synthesis involves the formation of end capped PU-prepolymer was formed through the reaction between polyethylene glycol (PEG) (Mn=600 g/mole, dimethylolpropionic acid (DMPA) and isophorone diisocyanate (IPDI) followed by the preparation of neutralized NCO terminated PU-prepolymer, which lead to the chain extension by using the chitosan. The dispersion of the obtained product was carried out by adding proper proportion of water. The synthesized CS-WDPUs were applied onto the different qualities of plain weave poly-cotton printed and dyed textile swatches by employing pad-dry-cure procedures. The textile assets of the treated and untreated textile swatches were assessed, as color fastness, pilling resistance, tear and tensile strength. The results showed that the chitosan incorporation into PU backbone has significant effect on the assets of treated textiles. These synthesized CS-WDPUs are eco-friendly bio-based finishes with potential applications for polyester/cotton textiles. 相似文献
59.
Pugliese Massimo Rettori Andrea Alberto Martinis Roberto Al-Rohily Khalid Al-Maashi Ali 《Precision Agriculture》2018,19(6):1049-1061
The date palm (Phoenix dactylifera L.) and other palm species have recently been threatened by the red palm weevil (RPW) Rhynchophorus ferrugineus Olivier, which is very difficult to be detected at early stage. This research tested non invasive approaches to detecting RPW including: a TreeRadarUnit? (TRU); a densitometer, a penetrometer used for evaluation of the standing trees stability; a thermal camera and a digital camera. The technologies were applied in Italy on 715 palms (173 P. dactylifera, 453 Phoenix canariensis Chabaud and 311 of other palm species), and on 86 adult date palms in Saudi Arabia. In Italy, the thermal camera showed a high accuracy (96.29%) compared to close visual observation over the following nine months. The digital camera did almost as well (92.57%). Tree Radar Unit and densitometer also showed good accuracy (83.33 and 88.89% respectively). In the Kingdom of Saudi Arabia, the thermal camera showed a good accuracy (77.73%) when compared to invasive diagnosis (i.e. cutting down and opening up palm trunks). The digital camera showed a lower accuracy of 66.67% due to the fact that the red weevil mainly attacks the base of the stem and therefore there are no visible symptoms on the crown shape that would be picked up in image analysis. TRU gave good results (74.73% compared to invasive diagnosis), with the best accuracy at ground level (80.65%). The densitometer results were similar to the TRU case, with higher accuracy (82.26% compared to invasive diagnosis) and the highest at ground level (87.10%). 相似文献
60.
Comparative effect of drought duration on growth,photosynthesis, water relations,and solute accumulation in wild and cultivated barley species 下载免费PDF全文
Maroua Mejri Kadambot H. M. Siddique Tark Saif Chedly Abdelly Kamel Hessini 《植物养料与土壤学杂志》2016,179(3):327-335
Drought is a major factor limiting crop production worldwide. Barley is a well‐adapted cereal that is largely grown on dry marginal land where water and salinity are the most prevalent environmental stresses. This study was carried out to investigate the effects of drought stress and subsequent recovery on growth, photosynthetic activity, water relations, osmotic adjustment (OA), and solute accumulation of wild (Hordeum maritimum) and cultivated barley (H. vulgare L.). In a pot experiment, 60 d old seedlings were subjected to drought stress for 0, 7, 14, 21, or 28 d, and then re‐watered to recover for up to 21 d. Plants were harvested at the end of each of these drought/recovery treatments. Drought significantly reduced fresh and dry weights at the whole‐plant level, photosynthetic activities, and solute and water potentials, while increasing leaf Na+ and K+ concentrations. The adverse effects of drought on growth were more marked in cultivated barley than in wild barley and the reverse was true for photosynthetic activities. During recovery, all wild barley seedlings completely recovered. For cultivated barley seedlings, rehydration had a beneficial effect on growth and photosynthesis, independent of treatment duration, but complete recovery did not occur. The reduction in leaf solute potential at full turgor in drought‐stressed barley, relative to the control, suggests active OA which was more significant in wild barley than in cultivated barley. OA was mainly due to the accumulation of inorganic (K+ in cultivated barley and Na+ in wild barley) and organic (soluble sugars and proline) solutes. The results suggest that OA is an important component of the drought‐stress adaptation mechanism in wild barley, but is not sufficient to contribute to drought tolerance in cultivated barley. In the latter species, the results show that even short periods (as little as 7 d) of water deficit stress had considerable long‐term effects on plant growth. 相似文献