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1.
The present investigation describes detection of a mammalian-like electropherogroup A rotavirus in chicken with diarrhoea. This also records the first detection of a rotavirus in an avian species from India. During the investigation 75 diarrhoeic faecal samples collected from adult chicken were screened for the presence of group A rotavirus antigen by sandwich ELISA. All three samples positive for rotavirus antigen revealed 11 bands of RNA in polyacrylamide gel electrophoresis (PAGE). In contrast to avian group A rotavirus, segment 5 was found to migrate closer to 6 as is the case with mammalian group A rotaviruses. Segments 7, 8 and 9 were found to migrate as a tight triplet, which is characteristic of group A rotavirus.  相似文献   
2.
Objective To evaluate standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals, as techniques for obtaining tissue for assessment of copper status. The techniques were evaluated with respect to ease of use and effect on the animal.
Procedure Twenty of 24 Thoroughbred mares and 21 of their foals were biopsied. The animals were part of a larger study of the effect of copper supplementation on copper status and the prevalence of developmental orthopaedic disease. Livers were also collected from unrelated horses and sampled to investigate the variability in the distribution of copper in liver tissue.
Result The biopsy technique caused no lasting effect on the mares, but there was an increased risk of viscus penetration associated with taking multiple biopsy cores. The use of ultrasonography to scan the target area for the liver identified four cases that were not appropriate candidates for liver biopsy, because of large intestine being located in the biopsy area. In the foals there were no serious postoperative adverse effects, nor was there any evidence of problems caused by the procedure when the abdomen was examined post-mortem at 5 months of age. In livers collected to investigate the variability of copper concentration, copper appeared to be relatively evenly distributed through the liver.
Conclusion Standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals are convenient procedures for obtaining liver tissue for assessing copper status in horses. The use of ultrasound to identify liver tissue is recommended, especially in older mares.  相似文献   
3.
The effect of a bronchodilator (or ciprenaline sulphate) and intravascular oxygen releaser (sodium dihydrogen orthophosphate) on the host in experimental Dictyocaulus filaria infection was studied. Fifteen male lambs of Dorset-Muzaffarnagri breed, aged 4-6 months, were divided into four groups of four (infected bronchodilator), four (infected i.v. O2 releaser), four (infected untreated controls) and three (uninfected controls). The administration of i.v. O2 releaser helped in increasing the length of useful patency, estimated total larval production and survival rate of D. filaria producer lambs. The administration of I.V. O2 releaser and bronchodilator helped in efficiently restoring the altered values of blood pH, haemoglobin, packed cell volume, erythrocyte sedimentation rate and osmotic fragility of erythrocytes to near normal levels. However, the blood clotting time and level of lactate dehydrogenase activity remained altered and followed a course typical of ovine dictyocauliosis.  相似文献   
4.
Genetic Resources and Crop Evolution - Correcting taxonomic misidentifications is crucial to ensuring the conservation and use of wild relatives in crop breeding programmes. Macrotyloma...  相似文献   
5.
Jan  Sami  Khan  M. N.  Jan  Sofora  Zaffar  Aaqif  Rashid  Rizwan  Khan  M. A.  Sheikh  F. A.  Bhat  M. Ashraf  Mir  R. R. 《Genetic Resources and Crop Evolution》2022,69(2):661-676
Genetic Resources and Crop Evolution - Barley (Hordeum vulgare L.) is one of the principal cereal crops grown in Western-Himalayas of India. A set of 105 barley genotypes including 38...  相似文献   
6.
7.
Summary 1201 tomato cultivars, breeding lines and accessions of Lycopersicon species were screened for tomato leaf curl virus (TLCV) under field and laboratory conditions during summer seasons of 1986 to 1989. Two lines of L. hirsutum (PI 390658 and PI 390659) and 2 lines of L. peruvianum (PI 127830 and PI 127831) were resistant to TLCV infection. These accessions did not produce any leaf curl symptoms either in field or after inoculation by whitefly Bemisia tabaci with TLCV. Adult whiteflies died within 3 days after releasing on resistant accessions (PI 390658, PI 390659, PI 127830), whereas the whiteflies survived upto 25 days on susceptible tomato cultivars. Under field conditions 0–4 and 5–25 adult whiteflies were observed on resistant and susceptible cultivars respectively. Hybridization was effected using the popular tomato cultivars Arka Sourabh, and Arka Vikas, as the female parents and the resistant Lycopersicon wild species as the pollen parents, to incorporate the resistant gene(s) into the edible tomatoes.  相似文献   
8.
Summary A population improvement programme in pyrethrum had progressively increased the mean pyrethrins content from 1.33 percent in the unselected base population to 1.97 percent in the population developed after one cycle of each of mass and recurrent selections. The selection had also increased the range of variation and the relative frequency of desirable plants.  相似文献   
9.
A Brassica juncea line carrying an introgression from Moricandia arvensis restored male fertility to two cytoplasmic male‐sterile (CMS) B. juncea lines carrying either M. arvensis or Diplotaxis catholica cytoplasm. Genetics of fertility restoration was studied in the F1, F2, F3 and backcross generations of the cross between CMS and fertility‐restorer lines. No male‐sterile plants were found in F1‐F3 generations of the cross between CMS [M. arvensis] B. juncea and the restorer. However, a 1: 1 segregation for male sterility and fertility was observed when the F1 was pollinated with non‐restorer pollen from a euplasmic line. These results clearly show that restoration is mono‐genic and gametophytic. In CMS lines carrying D. catholica cytoplasm, the restorer conferred male fertility to the F1 and showed 3: 1 and 1: 1 segregations for male fertility and sterility in F2 and BC1 generations, respectively, indicating a monogenic, sporophytic mode of fertility restoration. The results were also supported by pollen stainability in the F1 which was about 65% in M. arvensis‐based CMS and >90% in D. catholica‐based CMS. The above results are discussed in the light of previous molecular studies which showed association between CMS and atpA in both systems.  相似文献   
10.
Identification of a small core germplasm set representing the available genetic diversity is essential for its proper evaluation and subsequent utilization in rice improvement programmes. For constituting a small diverse mini‐core panel of Indian rice germplasm, a representative set of 6912 accessions drawn based on their geographic origin from the whole rice germplasm collection available in the National Gene Bank was genotyped using 36 microsatellite markers. Automated fragment analysis of amplicons yielded a total of 435 alleles, with an average 12.4 and range of 3–29 alleles per locus. Polymorphism information content (PIC) ranged from 0.08 (RGNMS190) to 0.86 (RM552) with an average of 0.528. Based on genotyping data, a mini‐core consisting of 98 genotypes was identified. Ninety‐four per cent of the alleles present in the core set were present in the mini‐core. The identified small but diverse panel will be useful for further intensive trait‐specific evaluation and utilization in allele mining.  相似文献   
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