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71.
Kumar N Jadhao SB Jha AK Kumar K Chandan NK Akhtar MS Aklakur M Kumar S Rana RS 《Fish physiology and biochemistry》2012,38(5):1343-1353
A 2-month preliminary study was conducted to delineate the effect of dietary methyl donors (choline, betaine, and lecithin) on the growth performance and metabolic status of Labeo rohita fingerlings subjected to endosulfan alone and in combination with elevated temperature. Four iso-caloric and iso-nitrogenous diets viz. basal diet, betaine-supplemented diet, choline-supplemented diet and lecithin-supplemented diet were prepared and fed to the different experimental groups throughout the experimental period as per the design. Two hundred and seventy fingerlings (average weight 7.95?±?0.04?g) were randomly distributed in six treatment groups each having three replicates. The experimental groups were as follows: fish subjected to normal water (without endosulfan) and fed with control diet (control group T(0)), fish subjected to endosulfan-treated water and fed with control diet (T(1)), fish subjected to concurrent exposure of endosulfan and elevated temperature and fed with control diet (T(2)), fish subjected to endosulfan and elevated temperature and fed with choline-supplemented diet (T(3)), fish subjected to endosulfan and temperature and fed with betaine-supplemented feed (T(4)), and fish subjected to endosulfan and temperature and fed with lecithin-supplemented feed (T(5)). The result shows that in both the groups, that is, endosulfan exposed and concurrent exposure to endosulfan and elevated temperature group of L. rohita the growth performance like percentage weight gain, feed conversion ratio and specific growth rates were significantly different (P?0.01) when fed with supplemented diet compared with control fed group. The liver LDH and MDH activity were significantly lower in lecithin, betaine, and choline fed groups. The muscle AST as well as G6PDH, AST, and ALT did not vary but liver ALT, gill and liver ATPase, intestine ALP, muscle and liver glycogen varied significantly with dietary supplementation. The liver and gill glutathione-S-transferase (GST) activities were significantly lower in methyl donors-supplemented groups and brain AChE activity showed lower inhibition in supplemented groups in both endosulfan alone and concurrently exposed endosulfan and temperature groups. The result obtained in this study concludes that inclusion of methyl donors, particularly lecithin and betaine in feed as nutritional supplements have potential to improve growth and stress mitigating effect in L. rohita fingerlings. 相似文献
72.
Shoaib Akhtar Gu-cheng LI Adnan Nazir Amar Razzaq Raza Ullah Muhammad Faisal Muhammad Asad Ur Rehman Naseer Muhammad Haseeb Raza 《农业科学学报》2019,18(2):460-470
Farmers in Pakistan continue to produce maize under various types of risks and adopt several strategies to manage those risks. This study is the first attempt to investigate the factors affecting the concurrent adoption of off-farm income diversification and agricultural credit which the farmers use to manage the risk to maize production. We apply bivariate and multinomial probit approaches to the primary data collected from four districts of Punjab Province in Pakistan. The results show that strong correlations exist between the off-farm diversification and agricultural credit which indicates that the use of one risk management strategy leads to another. The findings demonstrate that education, livestock number, maize farming experience, perceptions of biological risks and risk-averse nature of the growers significantly encourage the adoption of diversification as a risk management tool while farm size inversely affects the adoption of diversification. Similarly, in the adoption equation of credit, maize farming experience, farm size, perceptions of price and biological risks and risk attitude of farmers significantly enhance the chances of adopting agricultural credit to manage farm risks. These findings are important for the relevant stakeholders who seek to offer carefully designed risk minimizing options to the maize farmers. 相似文献
73.
Muhammad Zahid Mumtaz Muhammad Saqib Ghulam Abbas Javaid Akhtar Zia-ul Qamar 《Journal of plant nutrition》2018,41(2):233-242
A field experiment was conducted under two natural field conditions at the Research Farm (normal soil) and Proka Farm (salt-affected soil) of The Institute of Soil and Environmental Sciences (ISES), University of Agriculture, Faisalabad, Pakistan, to evaluate the performance of 11 rice genotypes in normal and salt-affected conditions. The experiment was laid out in randomized complete block design (RCBD) with three replications. The gas exchange attributes were measured at vegetative stage whereas the grain and straw yields and the yield components were recorded at maturity. After harvesting, the ionic parameters including sodium (Na+) and potassium (K+) were determined. Afterward, grain quality in terms of length, width, milling recovery, broken fraction, and chalkiness was also determined for the selected genotypes. Salt-affected conditions adversely affected the physiology, yield, and quality of the tested genotypes. The genotypes KS-282 followed by Shaheen Basmati showed significantly higher photosynthetic rate, transpiration rate, and stomatal conductance under both normal and salt-affected conditions, whereas the genotypes 99404 followed by 99417 showed minimum values of gas exchange attributes. The grain and straw yields were the highest in the case of KS-282 at both sites, whereas the lowest grain and straw yields were observed in the case of 99440 followed by 99417 under both normal and salt-affected conditions. Regarding the quality attributes, Super Basmati produced longer grains but with higher broken fraction and lower milling recovery, whereas the reverse was observed in the case of KS-282. 相似文献
74.
Antibody Prevalence and Risk Factors for Toxoplasma gondii Infection in Women from Multan,Pakistan 下载免费PDF全文
M. M. Nazir M. Akhtar A. Maqbool A. Waheed M. A. Sajid M. A. Ali M. Oneeb M. A. Alam A. N. Ahmad N. Nazir S. Fatima D. S. Lindsay 《Zoonoses and public health》2017,64(7):537-542
Toxoplasma gondii infections are prevalent in humans and warm‐blooded animals. Maternal infections during pregnancy may have devastating consequences for transplacentally infected neonates. This study was conducted to examine the seroprevalence of antibodies to T. gondii in pregnant women of childbearing age and determine risk factors associated with pregnancy history, pet ownership, social and cultural factors at Nishtar Hospital, Multan. Samples were collected from 403 women and examined using a commercially available enzyme‐linked immunosorbent assay (ELISA). The overall prevalence of antibodies to T. gondii was 17.6% (71) in the 403 samples collected from women. Antibodies to T. gondii were present in 19.4% (45) of 232 pregnant women and 15.2% (26) of the samples from 171 non‐pregnant women. This study identified miscarriage history, pet ownership, type of residence, marital status, source of drinking water and eating habits as significant (P < 0.05) risk factors associated with the presence of antibodies to T. gondii infection. Seroprevalence was not significantly different (P > 0.05) in women from different ethnic groups based upon lifestyle and culture. 相似文献
75.
76.
Phytosociological parameters, soil and temperature conditions, importance values of species, life form, leaf size, and biomass
were investigated at the village Tabai during autumn 2006. There was very little difference in air and soil temperature due
to similar elevation. There was a great difference in biomass production for various stands. The original vegetation structure
has been altered due to deforestation and overgrazing. There is a need for restoration of the habitat. 相似文献
77.
Yasmin Akhtar Murray B. Isman Lourdes A. NiehausChi-Hoon Lee Hoi-Seon Lee 《Crop Protection》2012,31(1):8-14
We investigated the feeding deterrent effects and toxicity of naturally occurring and synthetic quinones to the cabbage looper, Trichoplusia ni. Feeding deterrent effects were determined via a leaf disc choice bioassay. Based on DC50 values, 1,4-naphthoquinone was the most active antifeedant (DC50 = 1.8 μg/cm2) followed by juglone (DC50 = 2.1 μg/cm2), 2-methoxy-1,4-naphthoquinone (DC50 = 2.6 μg/cm2), plumbagin (DC50 = 3.3 μg/cm2), and 2,3-dimethoxy-5-mehtyl-1,4-benzoquinone (DC50 = 4.2 μg/cm2) in third instar cabbage looper larvae. 2-Bromo-1,4-naphthoquinone, 2-chloro-3-morpholino-1,4-naphthoquinone, 1,8-dihydroxy-anthraquinone, 2-methyl-1,4-naphthoquinone and naphthazarin had DC50 values ranging from 8.4 to 10.1 μg/cm2. Juglone and plumbagin were able to provide protection to intact cabbage plants in a greenhouse experiment. Cabbage looper larvae consumed less leaf area and weighed less on cabbage plants treated with either of these naturally occurring quinones. Most of the quinones demonstrated levels of antifeedant activity greater than neem, a positive control, in laboratory bioassays. The level of activity for juglone was comparable to neem in the greenhouse experiment. There was also a reduction in the number of larvae on treated plants compared with the negative control. Structure-activity relationships suggest that the antifeedant effects of the tested quinones depend on the number and position of hydroxyl and methoxyl substituents of quinones. Most of the quinones were of medium-low toxicity to third instar cabbage looper larvae via topical administration. Some of these quinones could have potential for development as commercial insect control agents targeting the feeding behavior of insects with minimal toxicity, provided that their impacts on non-target organisms and environment are minimal. 相似文献
78.
Prakash Sharma M. S. Akhtar A. K. Singh Partha Das Debajit Sarma 《Fish physiology and biochemistry》2016,42(6):1681-1698
Histomorphological changes in digestive tract of golden mahseer (Tor putitora) were examined in larvae [starting from hatching to 45 days post-hatching (dph)], fry, fingerling, and adult. Digestive tract appeared during hatching, on the dorsal side of yolk sac, as a straight tube with a narrow lumen. Mouth opening and appearance of liver and pancreas were observed at 2 dph, and subsequently anal opening, appearance of goblet cells in esophagus, and posterior intestine were evident at 3 dph. The remodeling of oral cavity in terms of epithelial stratification, appearance of taste buds, and goblet cells were observed in a window of 4–5 dph. Intestinal folding was found to be initiated at 8 dph. From 12 to 45 dph, thickening of oral and esophageal mucosal/extramucosal layers, increase in intestinal folding, increases in the density of goblet cells in entire gut were observed. Within the same time window, other histological changes such as disappearance of vacuoles in liver, and abundance of zymogen granules in pancreas were also observed. Supranuclear vesicles in mid-to-posterior intestine were found to be prominent from first feeding to 45 dph; however, this phenomenon was no longer evident in fry and fingerling. Overall, the increase in intestinal folding and complexity of extramucosal layer were found to be continuous from the first appearance to adult, and this inferred the fact that the nutritional physiology, in terms of digestion and assimilation, progressively changes throughout the life stages of golden mahseer. Findings of this study will, therefore, help in preparing diets for different life stages of this fish, and in addition, the present information widens the understanding of digestive physiology of golden mahseer. 相似文献
79.
Performance of mono‐sex tilapia (Oreochromis niloticus) in rice field with different ditch size 下载免费PDF全文
Md. Akhtar Hossain Md. Anisur Rahman Mridha Abul Kalam Md. Azad Shah Md. Nahiduzzaman Md. Sharif Uddin 《Aquaculture Research》2015,46(8):1891-1901
The effects of ditch size on growth and production of mono‐sex tilapia, Oreochromis niloticus in rain fed concurrent rice–fish system were technically and economically evaluated for a period of 4 months. Three different ditch sizes were tried: 5%, 10% and 15% of the total cultivable rice field. The fish fingerlings stocking density (5000 ha?1) and management practices were similar in all plots. The water temperature, dissolve oxygen, pH, Secchi disc visibility, ortho‐phosphate, ammonia nitrogen and alkalinity were found to be in the range of 31.5–31.9°C, 5.10–5.27 mg L?1, 7.56–7.62, 34.81–35.41 cm, 0.88–0.96 mg L?1, 0.014–0.021 mg L?1 and 66.23–69.76 mg L?1, respectively, and all the values were found suitable for tilapia fish farming. Sediment organic matter, available nitrogen and phosphorous were increased significantly (P < 0.05) in all plots after cultivating the fish. Larger ditch size (15% of the total land area) resulted in significantly (P < 0.05) higher specific growth rate, survival and fish production compared with the smaller (5%) and medium (10%) ditch sizes. However, significantly (P < 0.05) higher net income and benefit–cost ratio were obtained in medium ditch size with the values of 2.6% and 3.6% higher than the smaller and larger ditch sizes respectively. It is concluded that rice–fish farming in a rain fed ecosystem of Bangladesh with medium ditch size and stocking density of 5000 ha?1 mono‐sex tilapia can achieve better economic return. 相似文献
80.
M. Ramzan M. Akhtar F. Muhammad I. Hussain E. Hiszczyńska-Sawicka A. U. Haq M. S. Mahmood M. A. Hafeez 《Tropical animal health and production》2009,41(7):1225-1229
Toxoplasmosis, an infection caused by Toxoplasma (T.) gondii Apicomplexa protozoan, is widespread in humans and other animal species, having already been reported in many countries and
different climates. In Pakistan, no data is available on this aspect among food animals. This study was undertaken to determine
the seroprevalence of T. gondii infection in sheep and goats. A total of 200 serum samples from sheep and goats, were collected from urban area of Rahim
Yar Khan (Punjab), Pakistan and tested for Toxoplasmosis with a commercial latex agglutination kit (Eiken Chemical Co., Ltd.
Japan). The overall seroprevalence of Toxoplasmosis was 19%. Goats had a significantly higher (p < 0.01) prevalence (25.4%)
as compared to the sheep (11.2%); and higher (p < 0.01) in the female (24%) than in the males (19%) for both species. In the
present study the male (both in sheep and goat) are found less seropositive T. gondii (OR = 0.23; 99% C.I. = 0.01, 1.81) as compared to female sheep and goat. The prevalence was significantly higher (p < 0.01)
in adult sheep than younger animals. Among both the sheep and goats the group from 1–1.5 years are highly seropositive (OR = 1.75;
99% C.I. = 0.47, 6.51) as compared to the group less than one year of age followed by the 2–2.5 years age group (OR = 1.63;
99% C.I. = 0.50, 5.74) whereas group with more than 3 years of age least seropositive. 相似文献