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1.
In the past five decades, constant research has been directed towards yield improvement in pigeonpea resulting in the deployment of several commercially acceptable cultivars in India. Though, the genesis of hybrid technology, the biggest breakthrough, enigma of stagnant productivity still remains unsolved. To sort this productivity disparity, genomic research along with conventional breeding was successfully initiated at ICRISAT. It endowed ample genomic resource providing insight in the pigeonpea genome combating production constraints in a precise and speedy manner. The availability of the draft genome sequence with a large‐scale marker resource, oriented the research towards trait mapping for flowering time, determinacy, fertility restoration, yield attributing traits and photo‐insensitivity. Defined core and mini‐core collection, still eased the pigeonpea breeding being accessible for existing genetic diversity and developing stress resistance. Modern genomic tools like next‐generation sequencing, genome‐wide selection helping in the appraisal of selection efficiency is leading towards next‐generation breeding, an awaited milestone in pigeonpea genetic enhancement. This paper emphasizes the ongoing genetic improvement in pigeonpea with an amalgam of conventional breeding as well as genomic research.  相似文献   
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By PCR using the ant(3")-Ia primer pair the aadA gene was detected in 34 streptomycin- and spectinomycin-resistant Salmonella enterica serotype Typhimurium strains. Out of them 12 belonged to DT104 and 22 to non-DT104 phage type. Using different primer combinations it was demonstrated that this gene was integron-associated in all cases: in the DT104 strains it was generally contained by a 1 kb integron while in the majority of the non-DT104 strains by a 2.05 kb (less often by a 1.9 or 1 kb) integron. In the case of integrons carrying multiple cassettes the cassette containing the aadA gene was located closer to the 3' end of the integron. The aadA genes of DT104 and non-DT104 strains were different: in the former group the aadA2 gene, while in the latter group (constituted by strains of five different phages types as well as unclassifiable and untypable strains) the aadA1 gene could be identified. The RH50/RH51 primer pair described by Collis and Hall (1992) proved to be suitable for rapid discrimination between the aadA1 and aadA2 genes on the basis that the RH51 primer bound exclusively to the aadA2 gene.  相似文献   
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Forty-six cats with clinical haemobartonellosis were studied; 75 per cent of the cats of known age were two-and-a-half years old or younger, 50 per cent were intact males and 19.5 per cent were castrated males. The predominant signs of the disease were tachypnoea, lethargy, depression, anorexia, infestation with fleas, pale mucous membranes, icterus, emaciation, dehydration, splenomegaly, anaemia, leucocytosis, increased activities of alanine aminotransferase and aspartate aminotransferase, and azotaemia. Thirty-eight per cent of the cats that were tested for feline leukaemia virus (FeLV) antigen were positive, and 22 per cent of those tested for feline immunodeficiency virus (FIV) antibodies were positive. The prevalence of both FeLV and FIV was much higher than in the general Israeli cat population. The cats infected with both Haemobartonella felis and FeLV had a significantly lower body temperature, were more anaemic and the mean cell volume of their erythrocytes was greater than in the cats with haemobartonellosis alone.  相似文献   
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Therapy of canine dirofilariois due to Dirofilaria repens is indicated for dogs suffering from clinical signs of this disease, such as dermal swelling, sub-cutaneous nodules and pruritus. It is also important in order to decrease the risk of infection to other dogs and humans in the vicinity of the infected animal when suitable mosquito vectors are present. Combined therapy with the arsenic adulticide melarsomine and the avermectin microfilaricidal doramectin was effective in clearing infection with D. repens in a dog. The number of microfilariae dropped from 17 microl(-1) blood pre-treatment to 7 microl(-1) following the first adulticide injection and reached 0 a day after the microfilaricidal administration. The dog remained negative for D. repens microfilaremia during a follow-up period of 90 days. Euthanasia and necropsy performed 3 months after the initiation of therapy due to a progressive neoplastic disease revealed no evidence of filariae.  相似文献   
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Reports on the internationally emerging significance of multiresistant zoonotic Salmonella in animals and man prompted studies to estimate the significance of multiresistant Salmonella enterica subspecies enterica serotype Typhimurium (S. Typhimurium) phage type DT104 of animal origin in Hungary. A collection of 231 strains (primarily of goose, turkey, poultry and porcine origin from the years 1997-1998) was tested for resistance against 7 selected antibiotics (ampicillin, chloramphenicol, enrofloxacin, nalidixic acid, streptomycin, tetracycline and sulphamethoxazole). Strains with resistance against 3 or more were defined as multiresistant. All strains were phage typed using Felix-Callow's S. Typhimurium phage typing system, and 91 of them (suspect DT104) were also typed according to Anderson's definitive typing (DT) system. In this study, 14% of animal strains from 1997-1998 was classified as DT104, for which turkey, pig and duck seemed to be the main carriers, and the multiresistant non-DT104 strains represented a further 6% of this collection. The prevalence of DT104 was highest among strains of turkey origin (50%), followed by strains of pig (29%), chicken (25%), duck (19%), and goose (3%) origin. The other DT104 related phage types (DT12 and U302) were only detected in the case of 4 strains (2 of porcine, and one each of turkey and of goose origin). The DT104 corresponded to the Felix-Callow types 2/3 or 2c/3 in each case, except in the case of 3 turkey strains where they corresponded to type 35/3. Nalidixic acid resistance was detected in all multiresistant turkey strains and in some of other animal origin but none of these strains were resistant to enrofloxacin. A retrospective analysis (based on the above relationship) indicated that S. Typhimurium strains corresponding to DT104 could be present and increase in the Hungarian farm animal population from about 2% to 20% between 1985 and 1990, in a manner similar to the emergence of human DT104, as reported elsewhere (Pászti et al., 2000). The 91 suspect DT104 strains were also tested for plasmid profile and for spvC gene indicating the presence of the large serotype specific plasmid (Ssp). No characteristic plasmid profile could be attributed to S. Typhimurium DT104. The serovar-specific large plasmid was detected by PCR for spvC in 100% of DT104 strains and in 77% of the non-DT104 strains. The virulence of two DT104 strains was tested in orally infected day-old chicks and compared with virulence of 4 non-DT104 strains. Higher colonizing virulence of DT104 strains could be established as compared to the other strains.  相似文献   
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The objective of this survey was to investigate the prevalence of Hepatozoon infection in dogs in the rural and urban areas of Uberlândia, Brazil by PCR and molecular characterization. DNA was obtained from blood samples collected from 346 local dogs from both genders and various ages. Seventeen PCR products from positive blood samples of urban dogs and 13 from the rural dogs were sequenced. Partial sequences of the 18S rRNA gene indicated that all 30 dogs were infected with Hepatozoon canis similar in sequence to H. canis from southern Europe. Four local dog sequences were submitted to GenBank (accessions JN835188; KF692038; KF692039; KF692040). This study indicates that H. canis is the cause of canine hepatozoonosis in Uberlândia and that infection is similarly widespread in rural and urban dogs.  相似文献   
8.
Ferritin and paraoxonase-1 (PON-1) were measured in dogs experimentally infected by Leishmania infantum (during experimental infection and following treatment) and also in naturally-infected dogs which presented different degrees of proteinuria. Experimentally-infected dogs were monitored for 7 months post-infection, then treated for 3 months with allopurinol, and their response to therapy was followed for 11 additional months. Naturally-infected dogs were staged based on the urine protein/creatinine (UPC) ratio into three groups as follows: group 1 (non-proteinuric; UPC ratio: <0.2), group 2 (borderline proteinuric; UPC ratio: 0.2–0.5) and group 3 (proteinuric; UPC ratio >0.5). An increase in serum ferritin values and a decrease in PON-1 activity were observed 2 months after infection. Both analytes returned to preinfection values following treatment. Significantly higher concentrations of ferritin were observed in dogs classified as either borderline or proteinuric when compared with non-proteinuric dogs whereas serum PON-1 activity was decreased only in proteinuric dogs.  相似文献   
9.
Shrimp and fish pond soils: processes and management   总被引:7,自引:0,他引:7  
The pond bottom soil and the accumulated sediments are integral parts of ponds. Concentrations of nutrients, organic matter and microorganism density in the pond bottom are several orders of magnitude greater than in the water. The accumulation of organic sediments may limit pond intensification. The intensive organic matter degradation at the pond bottom and high sediment oxygen demand exceeds the oxygen renewal rate. This leads to the development of anoxic conditions in the sediments and at the sediment–water interface. A series of anaerobic processes, affected by the redox potential of the system, are taking place. A large number of potentially toxic materials are generated. Among those are organic acids, reduced organic sulfur compounds, reduced manganese and sulfides.

Shrimp, as animals that normally live on or near the bottom, are exposed to conditions on the pond bottom. Exposure to toxic materials endanger the well being of the cultured shrimp. Reduced feeding, slower growth, mortality and possibly higher sensitivity to disease are reported.

The rational use of aerators to minimize the area of sludge accumulation, construction of ponds to trap sludge, stirring sediments, chemical poising of the redox system and environmentally accepted treatment and reuse of drained sediments are means to control the conditions at the pond bottom.  相似文献   

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