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651.
Insulin-like growth factor 2 (IGF2) plays an important role in muscle growth and it might be used as a marker for the growth traits selection strategies in farm animals. The objectives of this study were to detect polymorphisms in exon 10 of IGF2 and to determine associations between these polymorphisms and growth traits in Egyptian water buffalo. PCR-single-strand conformation polymorphism (SSCP) and DNA sequencing methods were used to detect any prospective polymorphism. A novel single nucleotide polymorphism (SNP), C287A, was detected. It was a non-synonymous mutation and led to replacement of glutamine (Q) amino acid (aa) by histidine (H) aa. Three different SSCP patterns were observed: AA, AC, and CC, with frequencies of 0.540, 0.325, and 0.135, respectively. Association analyses revealed that the AA individuals had a higher average daily gain (ADG) than other individuals (CC and AC) from birth to 9 months of age. We conclude that the AA genotype in C287A SNP in the exon 10 of the IGF2 gene is associated with the ADG during the age from birth to 9 months and could be used as a potential genetic marker for selection of growth traits in Egyptian buffalo.  相似文献   
652.
Summary A reverse trancription-polymerase chain reaction (RT-PCR) assay was devised and shown to be sensitive and reliable for the detection of potato mop-top virus (PMTV) RNA sequences in the flesh of virus infected potato tubers, and in the roots and leaves of soil-bait plants. This assay was compared with an enzyme-linked immunosorbent assay incorporating PMTV specific monoclonal antibodies (TAS-ELISA). The tests were devised to improve the efficiency of detection of viruliferousSpongospora subterranea in agricultural soils, and PMTV in potato tubers. RT-PCR detected PMTV RNA sequences in the roots and leaves of bait plants after three weeks growth in viruliferous soil, three weeks before the bait plants themselves developed symptoms, and two weeks before the virus was detected by TAS-ELISA. Both RT-PCR and TAS-ELISA detected PMTV in the tubers of primary-infected potatoes. RT-PCR and TAS-ELISA were shown to be more sensitive and reliable than conventional baittests and sap inoculation methods for the detection and diagnosis of PMTV.  相似文献   
653.
Walleye dermal sarcoma virus (WDSV) is a type of retrovirus, which affects most of the adult walleye fishes during the spawning time. The virus causes multiple epithelial tumors on the fish’s skin and fins that are liable for more than 50% of the mortality rate of fish around the world. Till now, no effective antiviral drug or vaccine candidates have been developed that can block the progression of the disease caused by the pathogen. It was found that the 582-amino-acid (aa) residues long internal structural gag polyprotein of the virus plays an important role in virus budding and virion maturation outside of the cell. Inhibition of the protein can block the budding and virion maturation process and can be developed as an antiviral drug candidate against the virus. Therefore, the study aimed to identify potential natural antiviral drug candidates from the tropical mangrove marine plant Avicennia alba, which will be able to block the budding and virion maturation process by inhibiting the activity of the gag protein of the virus. Initially, a homology modeling approach was applied to identify the 3D structure, followed by refinement and validation of the protein. The refined protein structures were then utilized for molecular docking simulation. Eleven phytochemical compounds have been isolated from the marine plant and docked against the virus gag polyprotein. Three compounds, namely Friedlein (CID244297), Phytosterols (CID12303662), and 1-Triacontanol (CID68972) have been selected based on their docking score −8.5 kcal/mol, −8.0 kcal/mol and −7.9 kcal/mol, respectively, and were evaluated through ADME (Absorption, Distribution, Metabolism and Excretion), and toxicity properties. Finally, molecular dynamics (MD) simulation was applied to confirm the binding stability of the protein-ligands complex structure. The ADME and toxicity analysis reveal the efficacy and non-toxic properties of the compounds, where MD simulation confirmed the binding stability of the selected three compounds with the targeted protein. This computational study revealed the virtuous value of the selected three compounds against the targeted gag polyprotein and will be effective and promising antiviral candidates against the pathogen in a significant and worthwhile manner. Although in vitro and in vivo study is required for further evaluation of the compounds against the targeted protein.  相似文献   
654.
Single applications of different antisprouting agents like hot water treatment, spearmint oil and clove oil were carried out on potato cultivar “Lady Rosetta” to compare their efficacy with that of synthetic chloro isopropyl N-phenyl carbamate (CIPC). The tubers were stored at ambient storage conditions (25?±?2 °C) for 81 days to assess changes in their sugar-starch concentrations and antioxidant potential. Antioxidant potential in the tubers was assessed as their total phenolic concentrations and radical scavenging activities. In addition, the enzymatic activities were also determined in order to evaluate the possible depletion of these antioxidants as substrate during storage. Results revealed significant response of stored potatoes to all antisprouting agents compared with the control (P?≤?0.05). CIPC and clove oil applications maintained tuber dormancy almost twice as long (81 days) as observed in the control (45 days). Application of spearmint oil and hot water treatment maintained tuber dormancy for almost 2 months. However, it was associated with an increased percentage sprouting during the last weeks of storage. At the end of storage, the highest starch (16.83%) and lowest sugar (0.99%) concentrations were estimated after CIPC application and maximum total phenolic concentration (143.57 mg gallic acid equivalent (GAE)/100 g), and highest antioxidant activity (39.73%) were found after clove oil application. Enzymatic activities were not statistically different between CIPC and clove oil application during most of the storage period. Results showed that efficient replacement of CIPC with clove oil in the premium potato cultivar might be useful; this may avert related food safety and environmental issues and would also ensure organic potato storage.  相似文献   
655.
The relative abundance of isoprenoids and other volatile components in the aerial parts of Artemisia annua Linn. (Asteraceae) after different nutritional treatments was analyzed by GC and GC/MS. Hydro-distillation of untreated (control) plants yielded 0.28 ± 0.04% essential oil on fresh weight basis. Monoterpenes were predominant in the essential oil of which cis-limonene-1,2-epoxide (22.1%), artemisia ketone (11.5%), iso-pinocamphone (11.4%), thujyl alcohol (9.9%) and camphor (8.4%) were the major components. The essential oil distilled from A. annua treated with Azospirillum (2 ml/plant) amounted to 0.30 ± 0.03% of fresh weight and consisted mainly of neral (31.1%), β-caryophyllene (25.1%), artemisia ketone (10.0%), thujyl alcohol (9.4%), trans-bergamotene (8.5%) and spathulenol (4.8%). The essential oil from plants treated with basal N, P, K and S application (in the form of urea P2O5, K2O and gypsum at a rate of 120, 50, 100 and 50 kg/ha, respectively) amounted to 0.32 ± 0.03% of fresh weight and consisted mainly of thujyl alcohol (33.3%), β-caryophyllene (15.5%), cis-undec-5-ene (14.4%), artemisia ketone (6.0%), trans-nerolidol (5.8%) and undec-4-ene (4.6%). The hydrodistillation of A. annua treated with Glomus (Mycorrhizal soil 50 g/plant) yielded 0.50 ± 0.02% essential oil on fresh weight basis. The sesquiterpenes were predominant in this essential oil and consisted of β-caryophyllene (51.2%), trans-bergamotene (15.4%), α-gurjunene (14.3%), germacrene D (5.1%) and ledol (4.5%) as major components. The only monoterpenes in the essential oil were neral, nerol and pulegone (each less than 1%). These findings suggest that A. annua treated with Glomus lacks glandular trichomes—the primary sites of synthesis of monoterpenes.  相似文献   
656.
Early pregnancy diagnosis could be associated with decreased diagnostic accuracy or increased fetal loss, which might lead to increased culling. We determined the relationship between pregnancy diagnosis at various intervals after artificial insemination and subsequent calving for cows from five dairy herds in California. Palpations were done by either of two experienced veterinarians. Cows diagnosed pregnant at a first pregnancy examination 41 days or less after insemination were significantly less likely to subsequently have a calf than were cows diagnosed later.  相似文献   
657.
The effects of different estrus synchronization techniques on follicular development and estrus response were studied in 81 nulliparous Boer does. The does were divided into nine groups. Eight of the nine groups were synchronized with prostaglandin F2-alpha (PGF(2α)) or flugestone acetate (FGA) or their combinations, and the ninth group was a control group. In addition to the above combinations, four of the eight synchronized groups were given 5?mg follicle-stimulating hormone (FSH) and the remaining four groups were administered 300?IU equine chorionic gonadotrophin (eCG). Posttreatment follicular development was monitored until ovulation occurred using a real-time B-mode ultrasound scanner (Aloka, 500 SSD, Japan), with a 7.5-MHz transrectal linear probe. All the does from the synchronized groups that were given eCG exhibited oestrus while only 88.9% of the does synchronized with FSH showed estrus. The estrus response was observed to be the least among the does synchronized with PGF(2α) + FSH (33.3%) combination followed closely by the FGA + FSH (42.9%) combinations. It was observed that the combinations of FGA + PGF(2α) + FSH resulted in increased percentage of estrus response, duration of estrus, and ovulation. The number of follicles was higher (P?相似文献   
658.
SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) is a novel coronavirus strain that emerged at the end of 2019, causing millions of deaths so far. Despite enormous efforts being made through various drug discovery campaigns, there is still a desperate need for treatments with high efficacy and selectivity. Recently, marine sulfated polysaccharides (MSPs) have earned significant attention and are widely examined against many viral infections. This article attempted to produce a comprehensive report about MSPs from different marine sources alongside their antiviral effects against various viral species covering the last 25 years of research articles. Additionally, these reported MSPs were subjected to molecular docking and dynamic simulation experiments to ascertain potential interactions with both the receptor-binding domain (RBD) of SARS CoV-2’s spike protein (S-protein) and human angiotensin-converting enzyme-2 (ACE2). The possible binding sites on both S-protein’s RBD and ACE2 were determined based on how they bind to heparin, which has been reported to exhibit significant antiviral activity against SARS CoV-2 through binding to RBD, preventing the virus from affecting ACE2. Moreover, our modeling results illustrate that heparin can also bind to and block ACE2, acting as a competitor and protective agent against SARS CoV-2 infection. Nine of the investigated MSPs candidates exhibited promising results, taking into consideration the newly emerged SARS CoV-2 variants, of which five were not previously reported to exert antiviral activity against SARS CoV-2, including sulfated galactofucan (1), sulfated polymannuroguluronate (SPMG) (2), sulfated mannan (3), sulfated heterorhamnan (8), and chondroitin sulfate E (CS-E) (9). These results shed light on the importance of sulfated polysaccharides as potential SARS-CoV-2 inhibitors.  相似文献   
659.
OBJECTIVE: To determine the total number of Cryptosporidium parvum oocysts and Giardia spp cysts shed by dairy calves during the period when they are most at risk after natural infection. ANIMALS: 478 calves naturally infected with C. parvum and 1,016 calves naturally infected with Giardia spp. PROCEDURE: Oocysts or cysts were enumerated from fecal specimens. Distribution of number of oocysts or cysts versus age was used to determine the best fitting mathematic function. Number of oocysts or cysts per gram of feces for a given duration of shedding was computed by determining the area under the curve. Total number of oocysts or cysts was calculated by taking the product of the resultant and the expected mass of feces. Results: Intensity of Cparvum oocyst shedding was best described by a second-order polynomial function. Shedding increased from 4 days of age, peaked at day 12, and then decreased. An infected 6-day-old calf would produce 3.89 x 10(10) oocysts until 12 days old. Pattern of shedding of Giardia spp cysts was best described by exponential functions. Intensity of shedding increased from 4 days of age, peaked at day 14, and then decreased. An infected calf would produce 3.8 x 10(7) cysts from day 50 until day 56. CONCLUSIONS AND CLINICAL RELEVANCE: The large number of oocysts and cysts shed indicates that shedding by dairy cattle poses a risk for susceptible calves and people. Estimates reported here may be useful to aid in designing cost-effective strategies to manage this risk.  相似文献   
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