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Tahir Yaqub

Bio: Tahir Yaqub is an academic researcher from University of Veterinary and Animal Sciences. The author has contributed to research in topics: Newcastle disease & Population. The author has an hindex of 18, co-authored 115 publications receiving 1304 citations.


Papers
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Journal ArticleDOI
11 Jun 2009-PLOS ONE
TL;DR: Analysis of the gene sequences of all eight RNA segments from 12 viruses isolated between 2005 and 2008 indicates that during recent years the H9N2 viruses have undergone extensive genetic reassortment which has led to the generation of H9n2 viruses of novel genotypes in the Indian sub-continent.
Abstract: The impact of avian influenza caused by H9N2 viruses in Pakistan is now significantly more severe than in previous years. Since all gene segments contribute towards the virulence of avian influenza virus, it was imperative to investigate the molecular features and genetic relationships of H9N2 viruses prevalent in this region. Analysis of the gene sequences of all eight RNA segments from 12 viruses isolated between 2005 and 2008 was undertaken. The hemagglutinin (HA) sequences of all isolates were closely related to H9N2 viruses isolated from Iran between 2004 and 2007 and contained leucine instead of glutamine at position 226 in the receptor binding pocket, a recognised marker for the recognition of sialic acids linked α2–6 to galactose. The neuraminidase (NA) of two isolates contained a unique five residue deletion in the stalk (from residues 80 to 84), a possible indication of greater adaptation of these viruses to the chicken host. The HA, NA, nucleoprotein (NP), and matrix (M) genes showed close identity with H9N2 viruses isolated during 1999 in Pakistan and clustered in the A/Quail/Hong Kong/G1/97 virus lineage. In contrast, the polymerase genes clustered with H9N2 viruses from India, Iran and Dubai. The NS gene segment showed greater genetic diversity and shared a high level of similarity with NS genes from either H5 or H7 subtypes rather than with established H9N2 Eurasian lineages. These results indicate that during recent years the H9N2 viruses have undergone extensive genetic reassortment which has led to the generation of H9N2 viruses of novel genotypes in the Indian sub-continent. The novel genotypes of H9N2 viruses may play a role in the increased problems observed by H9N2 to poultry and reinforce the continued need to monitor H9N2 infections for their zoonotic potential.

163 citations

Journal ArticleDOI
TL;DR: The co-evolution of at least three different sub-genotypes reported here and the apparent close relationship of some of those genotypes from ND viruses isolated from wild birds, suggests that identifying wild life reservoirs may help predict new panzootics.

161 citations

Journal ArticleDOI
TL;DR: It was concluded that MOS or PM supplementation, alone or as a SYN, may reduce some of the detrimental effects of HS, whereas MOS alone or with their combination as a symbiotic may improve the absorption of trace minerals.

104 citations

Journal ArticleDOI
TL;DR: The results highlight the ease of spread of this group of H9N2 viruses between domesticated poultry and sparrows and show that sparrow’s need to be considered as a high risk species for transmitting H8N3 viruses between premises.
Abstract: Genetic changes in avian influenza viruses influence their infectivity, virulence and transmission. Recently we identified a novel genotype of H9N2 viruses in widespread circulation in poultry in Pakistan that contained polymerases (PB2, PB1 and PA) and non-structural (NS) gene segments identical to highly pathogenic H7N3 viruses. Here, we investigated the potential of these viruses to cause disease and assessed the transmission capability of the virus within and between poultry and wild terrestrial avian species. Groups of broilers, layers, jungle fowl, quail, sparrows or crows were infected with a representative strain (A/chicken/UDL-01/08) of this H9N2 virus and then mixed with naive birds of the same breed or species, or different species to examine transmission. With the exception of crows, all directly inoculated and contact birds showed clinical signs, varying in severity with quail showing the most pronounced clinical signs. Virus shedding was detected in all infected birds, with quail showing the greatest levels of virus secretion, but only very low levels of virus were found in directly infected crow samples. Efficient virus intra-species transmission was observed within each group with the exception of crows in which no evidence of transmission was seen. Interspecies transmission was examined between chickens and sparrows and vice versa and efficient transmission was seen in either direction. These results highlight the ease of spread of this group of H9N2 viruses between domesticated poultry and sparrows and show that sparrows need to be considered as a high risk species for transmitting H9N2 viruses between premises.

74 citations

Journal ArticleDOI
TL;DR: One year after a virulent Newcastle disease virus (vNDV) outbreak in Pakistan, the causative strain was present in vaccinated chickens of multiple farms despite the existence of high-average NDV-specific antibody titers (>4.75 log2).
Abstract: One year after a virulent Newcastle disease virus (vNDV) outbreak in Pakistan, the causative strain was present in vaccinated chickens of multiple farms despite the existence of high-average NDV-specific antibody titers (>4.75 log2). The data suggest a possible role of vaccinated birds as reservoirs of vNDV.

59 citations


Cited by
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01 Jun 2012
TL;DR: SPAdes as mentioned in this paper is a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler and on popular assemblers Velvet and SoapDeNovo (for multicell data).
Abstract: The lion's share of bacteria in various environments cannot be cloned in the laboratory and thus cannot be sequenced using existing technologies. A major goal of single-cell genomics is to complement gene-centric metagenomic data with whole-genome assemblies of uncultivated organisms. Assembly of single-cell data is challenging because of highly non-uniform read coverage as well as elevated levels of sequencing errors and chimeric reads. We describe SPAdes, a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler (specialized for single-cell data) and on popular assemblers Velvet and SoapDeNovo (for multicell data). SPAdes generates single-cell assemblies, providing information about genomes of uncultivatable bacteria that vastly exceeds what may be obtained via traditional metagenomics studies. SPAdes is available online ( http://bioinf.spbau.ru/spades ). It is distributed as open source software.

10,124 citations

Journal ArticleDOI
01 Mar 1941-Nature
TL;DR: In this article, Gray has written a book on diseases of poultry, Diseases of Poultry Their Aetiology, Diagnosis, Treatment and Control; with a Section on the Normal Anatomy and Physiology of the Fowl.
Abstract: VERY few veterinary surgeons have thought fit to write a book on diseases of poultry. Mr. Ernest Gray has done justice to the subject and is to be congratulated on his effort. A book of this size, written by one with specialized knowledge, will add to the value of any library or private bookshelf. Diseases of Poultry Their Aetiology, Diagnosis, Treatment and Control; with a Section on the Normal Anatomy and Physiology of the Fowl. By Ernest Gray. (Lockwood's Agricultural and Horticultural Handbooks.) Pp. x + 198 + 16 plates. (London: Crosby Lockwood and Son, Ltd., 1940.) 9s. 6d. net.

1,282 citations

Journal Article
TL;DR: In order to succeed academically, in the rigorous veterinary school curriculum, veterinary schools are looking for individuals with a highly developed science background, which is critical for admission.
Abstract: Transfer Requirements The following requirements for the major are subject to change without notice. To assure accuracy of the information on this sheet, you should consult with a counselor, the articulation officer, or review articulation agreements via the internet at www.assist.org Veterinary medicine uses problem-solving skills and in-depth knowledge to diagnose, treat and prevent animal diseases. It is the broadest and most comprehensive of all the health professions. The profession is concerned with enhancing the health, welfare, and productivity of animals and assuring the safety of animal products used by people. Veterinarians are highly trained medical professionals who provide for the health needs of all kinds of animals while maintaining sensitivity to human health and well-being. Most veterinarians in the United States are engaged in private practice. Other veterinarians work in a wide range of fields relating to public health, animal disease control, environmental protection, the biotechnology industry, higher education and research. Academic preparation for veterinary school takes place at the undergraduate level through a comprehensive educational experience with special emphasis in the sciences. In order to succeed academically, in the rigorous veterinary school curriculum, veterinary schools are looking for individuals with a highly developed science background. Since Pre-Veterinary is not a major, it is important to meet with a counselor during your first semester at El Camino College to help with the selection of classes. 1. Academic preparation and grade point average is critical for admission. Cumulative GPA, strong grades in science courses, and GPA in the last two years of undergraduate study are critical in the selection process. 2. Many, but not all veterinary schools require a bachelor's degree. In some instances, a bachelor's degree may make an applicant more competitive in the admission process. 3. Score on a standardized graduate admissions test (e.g. GRE, MCAT, and VCAT). Check with the individual program for the specific test required. 4. Strong letters of recommendation-Most schools require a minimum of three letters of recommendation. Some schools require on letter from a Doctor of Veterinary Medicine. 5. Undergraduate course of study-Veterinary schools are looking for both lower and upper division preparation. 6. Applicant's personal statement or narrative. 7. Extracurricular activities, work experience, community activities, motivation, individual character, personality, and other post-undergraduate experiences. 8. Animal related activities and/or animal related work experience-Most colleges are looking for a strong commitment to working with animals. Some require employment by a Veterinarian. 9. Personal interview. …

638 citations

Journal ArticleDOI
TL;DR: This review is focused on current status of neosporosis in animals based on papers published in the last five years and strategies for control and prevention are discussed.

559 citations

Journal ArticleDOI
TL;DR: The results showed that chronic HS reduces broiler production performance, intestinal microarchitecture, and increases adrenal hormone concentrations, and supplementation of the MOS prebiotic and the PM can partially lessen these changes.

293 citations