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排序方式: 共有239条查询结果,搜索用时 328 毫秒
231.
Iqbal Z Sarwar M Jabbar A Ahmed S Nisa M Sajid MS Khan MN Mufti KA Yaseen M 《Veterinary parasitology》2007,144(1-2):125-131
Anthelmintic activity of condensed tannins (CT) was evaluated both in vitro and in vivo. In vitro tests included egg hatch test and paralysis/mortality assay on adult Haemonchus contortus. In vivo anthelmintic effect was determined by faecal egg count reduction test in lambs. To this end, 18 lambs were divided into three groups (low tannin, high tannin and control). The lambs of low and high tannin groups were fed diets containing 2 and 3% CT while the control group was fed on diets without CT. In vitro trials showed a dose-dependent inhibition of nematode egg hatching; whereas, there was no effect of CT on adult H. contortus. In vivo trials indicated reduction in faecal egg counts in lambs fed diets containing CT. Feed intake and nutrient digestibility of CT-fed sheep was lower and nitrogen balance was higher as compared to control. Maximum weight gain was observed in animals fed diets containing 3% CT. The direct anthelmintic effect of CT, therefore, was evidenced by inhibited egg hatching; whereas, faecal egg counts reduction in sheep was through improved nutrient utilization. 相似文献
232.
Tariq Ali Abdur Rahman Muhammand Subhan Qureshi Muhammad Tariq Hussain Muhammad Shauib Khan Siraj Uddin Muhammad Iqbal Bo Han 《Tropical animal health and production》2014,46(7):1279-1285
Buffalo is an economically important dairy animal in South Asia but mostly ignored in research priorities. In this retrospective study, the effect of management practices and age of animal on the incidence of mastitis in Nili Ravi buffaloes was investigated. A total of 1,560 quarters of buffaloes (n?=?390) were screened by visual examination of the udder and milk (clinical mastitis) and California mastitis test (subclinical mastitis). Household data was collected on a predesigned questionnaire and analyzed. The prevalence of subclinical mastitis, clinical mastitis, and blind quarters was 41.8, 13.6, and 9.7 %, respectively. The highest prevalence was noted in the hind quarters and left side as compared to that in the forequarters and right side. This data significantly (p?0.05) supported the idea that larger herd size has more chances of mastitis, with the highest prevalence (40, 32, and 27 %) in the large, medium, and small herds, respectively. Stage of lactation was significantly (p?0.01) involved in mastitis, and the highest incidence (43.3 %) was noted in early lactation. Milk production of lactating buffaloes that ranged 6–10 l/day showed a higher rate of mastitis occurrence (p?0.05). The cleanliness condition of a farm also contributed significantly. Animal age significantly affected the incidence of mastitis. Results revealed that age of the animal has a positive correlation (R 2?=?0.772) with mastitis. This study concluded that some factors alone or in combination with other factors influence significantly the occurrence of mastitis, and to minimize the infection, these factors should be considered. The outcome of the study will be valuable for policy-making for positive management practices and implementation of preventive measures. 相似文献
233.
R Ejaz MS Ansari BA Rakha N Ullah AU Husna R Iqbal S Akhter 《Reproduction in domestic animals》2014,49(1):122-125
Cryopreservation process reduces lipids and phospholipids from buffalo bull spermatozoa. It was therefore hypothesized that supplementation of fatty acid to extender may improve the post‐thaw quality of buffalo semen. The objective was to evaluate the effect of arachidic acid supplementation in extender on post‐thaw quality of buffalo bull (Bubalus bubalis) spermatozoa. Semen was collected from three adult Nili‐Ravi buffalo bulls of similar age group with artificial vagina (42°C) for 3 weeks (replicate). Qualified semen ejaculates (n = 18) were split into four aliquots and diluted in tris–citric acid extender containing 0.0 (control), 5.0, 10.0 and 20.0 ng/ml at 37°C having approximately 50 × 106 spermatozoa/ml. Diluted semen was cooled to 4°C in 2 h and equilibrated for 4 h at 4°C. Cooled semen was filled in 0.5‐ml straws at 4°C, kept on liquid nitrogen vapours for 10 min and plunged in liquid nitrogen for storage. Thawing of frozen semen was performed after 24 h at 37°C for 30 s. Sperm progressive motility (%) was improved in a dose‐dependent manner by supplementing arachidic acid at 5.0, 10.0 and 20.0 ng/ml compared with control. Structural and functional integrity of sperm plasma membrane (%), number of acrosome‐intact live sperm (%) and sperm chromatin integrity (%) were better (p < 0.05) in extender having 5.0 ng/ml of arachidic acid compared with control. At 10.0 ng/ml, these values did not vary (p > 0.05) from those at 5.0 ng/ml. Further improvement in structural and functional integrity of sperm plasma membrane, number of acrosome‐intact live sperm and chromatin integrity was observed at 20.0 ng/ml of arachidic acid in extender. In conclusion, arachidic acid supplementation in extender improved the post‐thaw quality parameters of cryopreserved Nili‐Ravi buffalo bull spermatozoa. Among the arachidic acid concentrations studied, maximum improvement in post‐thaw semen quality parameters was observed at 20.0 ng/ml. 相似文献
234.
High grain yield and grain protein content, and early maturity are important traits in global bread wheat ( Triticum aestivum L.)-breeding programmes. Improving these three traits simultaneously is difficult due to the negative association between grain yield and grain protein content and the positive association between maturity and grain yield. We investigated the genetic relationship between maturity, grain yield and grain protein content in a population of 130 early maturing spring wheat lines in a high latitude (52–53°N) wheat-growing region of Canada. Grain protein content exhibited negative genetic correlation with maturity (−0.87), grain fill duration (−0.78), grain fill rate (−0.49), grain yield (−0.93) and harvest index (−0.71). Grain yield exhibited positive genetic correlation with maturity (0.69), rate (0.78) and duration (0.49) of grain fill, and harvest index (0.55). Despite the positive association between maturity and grain yield, and negative association between grain yield and grain protein content, higher yielding lines with medium maturity and higher grain protein content were identified. Broad-sense heritabilities were low (<0.40) for rate and duration of grain fill, grain protein content, spike per m2 , grains per spike, harvest index and grain yield, and medium to high (>0.40) for grain weight, days to anthesis and maturity, and plant height. Selection for longer preanthesis and shorter grain fill periods may help circumvent the negative association between grain yield and grain protein content. Selection for shorter grain fill periods and higher grain fill rate may be a useful strategy for developing early maturing cultivars with acceptable grain yields in northern wheat-growing regions. 相似文献
235.
Ammonia emission is one of the most important pathways of nitrogen loss from agricultural cultivated field. In this paper, we report the measurement of ammonia emission from paddy rice field obtained by surface application of urea fertilizer with water management. The main objective of the present study were to assess the amount of NH3 emission and the loss of nitrogen from paddy field as affected by various N doses, i.e., 0 (control), 90 (N1), 180 (N2), 270 (N3) and 360 (N4) kg ha-1, following field surface application of urea fertilizer with water management. Ammonia emissions were measured by continuous airflow enclosure method from plots fertilized with the application of surface urea. Increase in urea-N dosage increased NH3 emission thatwas measured from paddy rice field. Ammonia emission started immediately and was almost complete within 12 days after top dressing of urea application to the soils. Ammonia emissions were nearly constant in all treatments from 12 days after fertilizer application. Highest ammonia emission rate was 28 g/day and total amount of ammonia emission was 56.21 kg ha-1 for 360 kg N ha-1 dose. No remarkable observation was found about temperature for ammonia emission. Due to proper water management practices less emission was observed throughout the experiment period. The results also show that N loss through NH3 emission accounted for 11 to 16% during the ricegrowing season. These magnitudes of loss of N appear to be most important for environmental point of view. 相似文献
236.
Sher Muhammad Shahzad Azeem Khalid Muhammad Saleem Arif Muhammad Riaz Muhammad Ashraf Zafar Iqbal Tahira Yasmeen 《Biology and Fertility of Soils》2014,50(1):1-12
The present study was designed with the objective of improving the nodulation and growth of chickpea (Cicer arietinum L.) by integrating co-inoculation of Rhizobium sp. (Mesorhizobium ciceri) and plant growth promoting rhizobacteria (PGPR) carrying ACC (1-aminocyclopropane-1-carboxylate) deaminase activity with P-enriched compost (PEC) under irrigated and rainfed farming systems. PEC was prepared from fruit and vegetable waste and enriched with single super phosphate. The results demonstrated that co-inoculation significantly (P?<?0.05) increased the number of nodules per plant, nodule dry weight, pods per plant, grain yield, protein content, and total chlorophyll content under irrigated and rainfed conditions compared to inoculation with rhizobium alone. Integrating PEC with co-inoculation showed an additive effect on the nodulation and growth of chickpea under both farming systems. Analysis of leaves showed a significantly (P?<?0.05) higher photosynthetic rate and transpiration rate in comparison with inoculation with Rhizobium. Compared to irrigated farming system, co-inoculation with PEC under rainfed conditions was more beneficial in improving growth and nodulation of chickpea. Post-harvest soil analysis revealed that the integrated use of bioresources and compost enhanced microbial biomass C, available N content, dehydrogenase, and phosphomonoesterase activities. 相似文献
237.
Differential Utilization of Dissolved Organic and Inorganic Nitrogen by Wheat (Triticum Aestivum L.)
Zafar Iqbal Muhammad Khalid Nawaf Soleman Davey L. Jones 《Journal of plant nutrition》2014,37(13):2094-2107
A study was conducted under greenhouse conditions on wheat to investigate the utilization of dissolved organic nitrogen (N) in comparison with conventionally applied inorganic N sources (INS). Nitrogen was applied at a rate of 90 kg N ha?1 in an inorganic form, an organic high molecular weight (MW) form (casein, haemoglobin, albumin), and an organic low MW amino acid form (glycine, alanine, valine). Inorganic N sources recorded the maximum response (126% to 150%) in total dry matter (DM) production while dissolved organic nitrogen (DON) sources showed 61% to 116% increase in comparison to the control treatment. Glycine gave the maximum DM production, which was comparable with both INS treatments. In hydroponics, greater utilization occurred and the shoots had a higher N content in comparison to those grown in soil. The concentration of DON and NO3? in soil after wheat harvest was similar in all the treatments. 相似文献
238.
Muhammad Kasib Khan Muhammad Sohail Sajid Zafar Iqbal 《Research in veterinary science》2009,87(1):70-75
The present study reports the prevalence, effects of treatment and cost benefit analysis of bovine fasciolosis in five districts of Punjab Province viz Sargodha, Jhang, Muzaffargarh, Lodhran and Layyah. From each of the five districts, 80 animals were selected and fortnightly screened through standard coprological procedures for a period of one year for the presence of eggs of Fasciola species. Of 4800 faecal samples analyzed, 1222 (25.46%) were found positive for fasciolosis. The occurrence of Fasciola (F.) gigantica (22.40%) was higher (P < 0.05) than F. hepatica (3.06%). Highest month-wise prevalence (P < 0.05) of fasciolosis was found in winter (39.08%) followed in decreasing order by spring (29.50%), autumn (20.33%) and summer (12.92%). District-wise prevalence of fasciolosis was highest (P < 0.05) in Sargodha (40.31%) and lowest in Layyah (11.77%) while other districts were having intermediate values of prevalence of fasciolosis. Species-wise prevalence of fasciolosis was found higher (P < 0.05) in buffaloes (30.50%) as compared to cattle (20.42%). However, there were no age and sex-related differences (P > 0.05) in prevalence of fasciolosis. A strong positive association of grazing (OR = 1.81), mixed farming of small and large ruminants (OR = 1.39), stagnant pond bathing (OR = 2.24) and river/canal bathing (OR = 2.06) was found with the prevalence of fasciolosis as compared to stall feeding, separate farming of small and large ruminants and rivers/canal/ tap water bathing, respectively. Post-treatment average milk increase of 0.62 L per animal per day with 0.35% higher fat was observed in fasciolicide-treated animals with the cost benefit ratio of 3.9. The results provided significant data on the epidemiology of five districts of Punjab province which may be helpful for the planners and small holder dairy farmers for control of fasciolosis in the study districts. 相似文献
239.
Muhammad Ayaz Urte Stulpinaite Dalia Feiziene Vita Tilvikiene Kashif Akthar Edita Baltrėnaitė-Gedienė Nerijus Striugas Urooj Rehmani Sahib Alam Rashid Iqbal Monika Toleikiene Modupe Doyeni 《Soil Use and Management》2022,38(2):1307-1321
Management of heavy metal-contaminated soil under drought and other harsh hydrological conditions is critical for protecting soil ecosystem services. In this study, we examined the effect of pig manure digestate-derived biochar as a soil amendment (15 t ha−1) with N fertilizer (180 kg ha−1) on soil and plant heavy metal levels and nutrient availability under various moisture regimes (optimal moisture ~15%, drought condition ≤5%, and flooded condition ≥35% wt.). It was observed that biochar applications significantly decreased heavy metals in the spring wheat plants, lowering Cr by 90%, Ni by 50%, Cd by 9% and Pb by 34% compared to non-biochar (control) treatments. However, the pig digestate-derived biochar increased heavy metals in soil under all moisture regimes, increasing soil Cr by 21%, Ni by 43%, Cu by 55%, Zn by 70%, and Pb by 12%. The availability of macroelements also increased with the biochar applications under the optimum moisture regimes in both soil and plants, increasing Mg2+ by 11%, P by 4%, K+ by 50%, and Ca2+ by 56% in the soil, and Mg2+ by 13%, P by 69%, K+ by 29, and Ca2+ by 39% in plants. Biochar addition also improved chlorophyll fluorescence (CF) levels in the crop for the entire season (12th to 62nd day) and the aboveground crop biomass and dry matter contents both increased. Consequently, the use of pig manure digestate-derived biochar with N fertilizer under normal moisture conditions was able to reduce heavy metal availability to plants and thus could be used in contaminated soils to maintain better crop growth and development. 相似文献