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1.
Tropical Animal Health and Production - Avian influenza virus (AIV) H9N2 subtype is endemic in Iran and causes substantial economic loss to the growing poultry industry within the country. In this...  相似文献   
2.
Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms.  相似文献   
3.
The objective of this study was to evaluate the effects of organic and inorganic fertilizers on the yield and quality of sugar beet genotypes (Beta vulgaris L.). Therefore, a field trial was carried out in Peshawar, Pakistan, during the winters in 2012–2013. The field experiment was conducted in a randomized complete block design with split plots, having three replications. Fertilizer treatments (control, composted manure Higo Organic Plus at 5 t ha?1, Maxicrop Sea Gold seaweed extract at 5 L ha?1, farm yard manure at 10 t ha?1, inorganic nitrogen–phosphorus (NP) at 90:60 kg ha?1, NP at 120:90 kg ha?1 and NP at 150:120 kg ha?1) were allotted to main plots, while genotypes (Sandrina, Serenada and Kawe Terma) were allotted to the sub-plots. Plots treated with the application of NP at 120:90 kg ha?1 produced the highest beet yield (76.4 t ha?1) and sugar yield (11.1 t ha?1), and had the second highest polarizable sugar content (14.52%) and more economic return (Rs. 553,000 per hectare) as compared to control plots. Sugar beet genotype Serenada had significantly higher beet yield (55.5 t ha?1) and sugar yield (7.9 t ha?1) and a higher economic return (Rs. 380,000 per hectare) than the other genotypes. Sugar beet genotype Serenada supplied with NP at 120:90 kg ha?1is recommended for the general cultivation in the agro-climatic conditions of Peshawar valley.  相似文献   
4.
5.
This study evaluated the effect of specific calcium and magnesium ratios at two hardness values on reproductive performance and offspring quality of Macrobrachium rosenbergii brood‐females. Hatchery water containing 110.5 mg/L CaCO3 hardness was considered baseline as it has been used successfully to hatch and rear larvae and was used as the control treatment. At each hardness value of 150 and 190 mg/L CaCO3, four experimental water treatments were made in triplicate. Each treatment was adjusted using soluble salts (CaCl2·H2O, MgSO4·7H2O, and MgCl2·6H2O) to provide the hardness and calcium to magnesium ratios of 0:20, 20:80, 50:50, and 80:20 needed. Each of the experimental tanks (140 L) were stocked with six females and one male. The results indicated that both hardness and Ca:Mg ratios affect brood‐female reproductive qualitative parameters such as intermolt period, egg hatchability, egg dry weight, and egg‐clutch somatic index (ESI) parameters (P < 0.05) but not fecundity and eggs per spawn. The results revealed that brood‐females at 150 mg/L hardness showed greater reproductive performance than at 190 and 110.5 mg/L hardness. The findings also demonstrated that the treatment 50Ca50Mg at 150 mg/L hardness with 38.8 mg/L calcium and 12.9 mg/L magnesium had optimum reproductive performance and offspring quality for M. rosenbergii brood‐females.  相似文献   
6.
Interferon (IFN)-γ has been shown to be associated with immunity to Marek’s disease virus (MDV). The overall objective of this study was to investigate the causal relationship between IFN-γ and vaccine-conferred immunity against MDV in chickens. To this end, 3 small interfering RNAs (siRNAs) targeting chicken IFN-γ, which had previously been shown to reduce IFN-γ expression in vitro, and a control siRNA were selected to generate recombinant avian adeno-associated virus (rAAAV) expressing short-hairpin small interfering RNAs (shRNAs). An MDV challenge trial was then conducted: chickens were vaccinated with herpesvirus of turkey (HVT), administered the rAAAV expressing shRNA, and then challenged with MDV. Tumors were observed in 4 out of 10 birds that were vaccinated with HVT and challenged but did not receive any rAAAV, 5 out of 9 birds that were administered the rAAAV containing IFN-γ shRNA, and 2 out of 10 birds that were administered a control enhanced green fluorescent protein siRNA. There was no significant difference in MDV genome load in the feather follicle epithelium of the birds that were cotreated with the vaccine and the rAAAV compared with the vaccinated MDV-infected birds. These results suggest that AAAV-based vectors can be used for the delivery of shRNA into chicken cells. However, administration of the rAAAV expressing shRNA targeting chicken IFN-γ did not seem to fully abrogate vaccine-induced protection.  相似文献   
7.

The aim of this study was to investigate the possibility of improving the growth and physiological indices of plant and fish by adding different levels of ascorbic acid (vitamin C) to water in the aquaponic system using Nile tilapia (Oreochromis niloticus) and saffron plant (Crocus sativus). 240# fish (12.5?±?0.21 gr) and 120# saffron corms (2.8?±?0.12 gr) were randomly assigned to 15 experimental units and underwent treatments of adding 0 (control), 2, 4, 6, and 8 mg L?1 ascorbic acid to water, every 6 days, for 8 weeks. The fish final weight and subsequently other growth performance indices increased in the treatment of 4 mg L?1 vitamin C compared to other treatments (P?≤?0.05). Some growth performances of saffron plants such as saffron production, in treatment of 6 mg L?1, were significantly higher than the control group and reached from 17.34?±?0.27 mg flower?1 in the control group to 25.4?±?1.61 mg flower?1 in treatment of 6 mg L?1. Measuring the serum biochemical parameters of the fish showed that, in the treatment of 8 mg/L ascorbic acid, the cortisol content in the blood reached its maximum (21.49?±?2.42 µg dL?1). The trypsin activity in proximal intestine and mid-intestine significantly increased in treatments of 2, 4, and 6 mg L?1, respectively. The current experiment showed that, by adding 4–6 mg/L ascorbic acid to the aquaponic system water (every 6 days), the optimal levels of Nile tilapia and saffron plant growth performances would occur.

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8.
Plasmin is a protease in milk, which concentration is increased during mastitis. The aim of the study was design and characterize short, tailor made fluorogenic substrates for plasmin to see differences in plasmin activity in healthy milk compared to mastitic milk. According to the specificity matrix of plasmin, containing 125 currently known plasmin substrates, six novel plasmin specific substrates were designed and characterized. Eight other substrates were insensitive for plasmin, which was in line with our expectations. The plasmin-sensitive substrates showed no cross-reactivity with proteases from mastitogenic bacteria in vitro. A proof of concept to distinguish healthy milk from mastitic milk is described. Potentially, these substrates present a rapid alternative to the currently established methodologies to detect mastitis in milk.  相似文献   
9.
当前,基于正积温的度日模型广泛应用于冰川消融研究中,该模型的核心参数是度日因子。根据印度河上游Sachen、Gharko、Barpu冰川2014—2016年的物质平衡和气温实测资料,计算得到消融期内各冰川研究区的度日因子,并分析了度日因子的时空变化特征及影响因素。研究结果显示:Sachen、Gharko、Barpu冰川度日因子均值分别为2.83 mm?d-1?℃-1、3.74 mm?d-1?℃-1、3.91 mm?d-1?℃-1;各冰川度日因子皆随着海拔升高而递增,海拔递增率分别为0.003 7 mm?d-1?℃-1?m-1、0.007 4 mm?d-1?℃-1?m-1、0.004 1 mm?d-1?℃-1?m-1;对于同一观测点而言,度日因子不是一个常数,会随着时间的变化而改变,冰川度日因子随着年际变化呈增加的趋势;度日因子受表碛影响显著,度日因子整体上随着表碛厚度的增加而递减。然而表碛厚度低于2 cm时,表碛的覆盖作用促进了冰川的消融,表碛覆盖区冰川度日因子大于裸露区冰川;冰川朝向的变化对度日因子产生了一定的影响,面向阳坡的冰川度日因子随海拔递增率大于阴坡。  相似文献   
10.
To check the efficacy of potassium in alleviating oxidative stress under salt stress, salt-tolerant (Indent-1) and salt-sensitive (Red Ball) tomato (Lycopersicon esculentum Mill.) genotypes were exposed to three levels of sodium chloride (NaCl) (0, 75, 150 mM) and two levels of potassium (4.5 and 9 mM) in solution and foliar form. Thirty days of treatments revealed that increasing NaCl stress increased lipid peroxidation (malondialdehyde, MDA) and correspondingly the activity of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; and glutathione reductase GR) in both genotypes. However, higher potassium (K) level in solution or foliar spray during the salt-induced stress decreased MDA and antioxidant activity and increased the growth in salt-tolerant genotype than in the salt-sensitive genotype. Decrease in MDA concentration, activity of antioxidant enzymes, and increase in the growth of tomato plants by the application of potassium under salt stress suggest that potassium is an effective ameliorating agent against salt-induced oxidative damage.  相似文献   
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