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51.
In order to differentiate infectious bursal disease virus (IBDV) isolates/strains, a quick method of RT-PCR followed by restriction enzyme analysis of VP1 gene sequence is being reported for the first time. A 480 bp fragment, comprising one of the RNA dependent RNA polymerase motifs of VP1 gene sequence of an Indian classical virus, an attenuated vaccine strain, Georgia and two Indian field isolates, genetically similar to reported very virulent strains of IBDV, was amplified by RT-PCR. Restriction enzyme digestion of PCR products with Taq1 enzyme generated distinct profile for field isolates, different from the classical and attenuated viruses, whereas restriction profile with BstNI restriction enzyme was similar in all the viruses, irrespective of the pathotype. Therefore, the present results suggest that Taq1 digestion can be taken up for the differentiation of field isolates from the classical and vaccine strains. The sequence analysis of VPI gene of reported very virulent IBD viruses from Europe and Japan, using 'MapDraw' programme of Lasergene software, revealed similar restriction enzyme profile as in Indian field isolates.  相似文献   
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Objective To measure the plasma cortisol response in calves dehorned by four different methods (scoop, guillotine shears, saw, embryotomy wire) for 9 h after dehorning.
Design A physiological study with controls.
Procedure Horn amputation was carried out on calves restrained manually in a race.
Results The four methods of dehorning provoked similarly increased cortisol responses which lasted for 6 h. During the first hour after dehorning the plasma cortisol concentrations were similar to those following ACTH injection. The overall cortisol response to control handling was about 30% of the responses to dehorning.
Conclusions The similarity of the cortisol responses produced by the four methods of dehorning suggests that the distress experienced by calves following dehorning by amputation is similar regardless of method used.  相似文献   
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Degenerate primers based RT-PCR (previously described by [Avian Dis 26 (1997) 837]) has been used for the detection and differentiation of Newcastle disease (ND) viruses. Two sets of primers (A+B and A+C), with common forward primer and distinct reverse degenerate primers, designed from fusion protein gene encoding for cleavage site, could differentiate virulent and avirulent Newcastle disease viruses (NDV). Both sets of primers amplified "F" gene sequence of virulent (velogenic and mesogenic) viruses, whereas in avirulent strains, amplification was only with primer set A+C. Total 10 NDV isolates and two clinical samples including both known and unknown pathotypes, were checked. Based on amplification results 5 viruses were found to be virulent type and 6 as avirulent with one of the two clinical samples, earlier positive by RT-PCR using non-degenerate "F" gene specific primers was found negative in this study. The technique has been found to be a simple and quick for the detection and differentiation of virulent and avirulent NDV, which is important for control of the disease in the events of the outbreaks.  相似文献   
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Fish waste water nutrient recycling in an aquaponic system was studied under different stocking densities of Koi Carp, Cyprinus carpio var. koi, along with spinach, Beta vulgaris var. bengalensis. Fish growth performance, plant growth, nutrient dynamics, and nutrient removal and their dependence on different stocking densities, namely 1.4, 2.1, and 2.8, were observed, of the different combinations, fish stocked at 1.4 kg/m3 had the best growth. Percent nutrient removal (NO3–N, PO4–P, and K) was significantly higher at 1.4 kg/m3. Thus, 1.4 kg/m3 stocking density can be suggested as optimum for Koi Carp production in spinach aquaponic systems.  相似文献   
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Brucellosis is a zoonotic disease of great animal welfare and economic implications worldwide known since ancient times. The emergence of brucellosis in new areas as well as transmission of brucellosis from wild and domestic animals is of great significance in terms of new epidemiological dimensions. Brucellosis poses a major public health threat by the consumption of non-pasteurized milk and milk products produced by unhygienic dairy farms in endemic areas. Regular and meticulous surveillance is essentially required to determine the true picture of brucellosis especially in areas with continuous high prevalence. Additionally, international migration of humans, animals and trade of animal products has created a challenge for disease spread and diagnosis in non-endemic areas. Isolation and identification remain the gold standard test, which requires expertise. The advancement in diagnostic strategies coupled with screening of newly introduced animals is warranted to control the disease. Of note, the diagnostic value of miRNAs for appropriate detection of B. abortus infection has been shown. The most widely used vaccine strains to protect against Brucella infection and related abortions in cattle are strain 19 and RB51. Moreover, it is very important to note that no vaccine, which is highly protective, safe and effective is available either for bovines or human beings. Research results encourage the use of bacteriophage lysates in treatment of bovine brucellosis. One Health approach can aid in control of this disease, both in animals and man.  相似文献   
59.
AFLP technique was used to assess genetic diversity in 72 soybean varieties under cultivation in India. Selected 12 AFLP primer pairs produced 1319 products of which 1257 were polymorphic (95%). Wide variations were observed for the number of amplification products, percent polymorphism and average polymorphism information content (PIC). The Jaccard's similarity indices (J) based on the AFLP profiles of the 72 soybean varieties were subjected to UPGMA cluster analysis. The dendrogram generated revealed four major clusters, which were strongly supported by the high bootstrap values obtained from analyses of 1000 bootstrap samples. In addition, the Mantel's test for cophenetic correlation with r = 0.955 indicated very good fit of the varieties to a group in the cluster analysis. Some correspondence between the clustering pattern and the pedigree, place of release or target area of the variety was observed. Overall moderately high genetic diversity was observed which appears to be due to the higher genetic diversity prevalent in 12 of the varieties included in three diverse clusters and was indicative of the need to include more diverse germplasm in the soybean improvement programs.  相似文献   
60.
Summary A strong epidemiological association is known to exist between the consumption of grass pea and lathyrism. A neurotoxin, -N-Oxalyl-L-, -diaminopropanoic acid (ODAP) has been identified as the causative principle. This study was undertaken to investigate the mode of inheritance of the neurotoxin ODAP, flower and seed coat colour in grass pea. Five grass pea lines with low to high ODAP concentration were inter-crossed in all possible combinations to study the inheritance of the neurotoxin. Parents, F1 and F2 progenies were evaluated under field condition and ODAP analyzed by an ortho-phthalaldehyde spectrophotometric method. Many of the progenies of low x low ODAP crosses were found to be low in ODAP concentration indicating the low ODAP lines shared some genes in common for seed ODAP content. The F1 progenies of the low ODAP x high ODAP crosses were intermediate in ODAP concentration and the F2 progenies segregated covering the entire parental range. This continuous variation, together with very close to normal distribution of the F2 population both of low x low and low x high ODAP crosses indicated that ODAP content was quantitatively inherited. Reciprocal crosses, in some cases, produced different results indicating a maternal effect on ODAP concentration. Blue and white flower coloured lines of grass pea were inter-crossed to study the inheritance of flower colour. Blue flower colour was dominant over the white. The F2 progenies segregated in a 13:3 ratio indicating involvement of two genes with inhibiting gene interactions. The gene symbol LB for blue flower colour and LW for white flower colour is proposed.  相似文献   
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