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1.
Haemorrhagic pancarditis has been studied microscopically and ultrastructurally. Haemorrhages, oedema, mononuclear cell infiltration, degeneration, fragmentation, atrophy and lysis of myofibres, and extravascular localisation of the parasite were observed. 相似文献
2.
Nyaga Justine M. Onyango Cecilia M. Wetterlind Johanna Söderström Mats 《Precision Agriculture》2021,22(4):1217-1236
Precision agriculture (PA) has a huge potential for growth in sub-Saharan Africa (SSA), but it faces a number of social-economic and technological challenges. This study sought to map existing PA research and application in SSA countries following the methodology for systematic mapping in environmental sciences. After screening for relevance, the initial about 7715 articles was reduced to 128. Results show that most of the studies were conducted in countries with socio-economic and technological advancement, mainly South Africa followed by Nigeria and Kenya. The studies were conducted at various scales ranging from field to country level with field scale studies being the most common. Most studies were conducted in relatively small farms typical of most farmlands in SSA. Studies done in relatively large farms are fewer, and such farms would likely belong to a few organisations and individuals with high economic capacity. Many of these studies have been conducted by researchers from outside SSA and a combination of researchers from within and outside SSA. However, based on authorship of the articles, it appears that most of the studies conducted in SSA on precision agriculture have either involved or depended on non-African researchers. It is concluded that there have been significant strides towards use of precision agriculture in SSA. However, with about 21 countries having no research done, there exists greater potential for precision agriculture in the region. Besides, there is need for more research to investigate the low usage of precision agriculture for livestock management.
相似文献3.
Isaac R. Mulei Phillip N. Nyaga Paul G. Mbuthia Robert M. Waruiru Cheng Xu
ystein Evensen Stephen Mutoloki 《Journal of fish diseases》2019,42(5):751-758
Infectious haematopoietic necrosis virus (IHNV) is the causative agent of infectious haematopoietic necrosis, a disease of salmonid responsible for great economic losses. The disease occurs in most parts of the world where rainbow trout is reared but has not been previously reported in Kenya. In this study, rainbow trout fry and growers from two farms in Nyeri County were screened for IHNV. Whole fry (n = 4 from each farm) and kidney samples from growers (n = 15 and n = 6 from the two farms, respectively) were collected and preserved for cell culture examination or PCR analysis. Screening of samples was done by PCR followed by sequencing of the glycoprotein gene of the virus. Demonstration of the virus was done by propagation in EPC cells followed by the indirect fluorescence antibody test (IFAT). The results revealed the presence of IHNV at low prevalence of 0.1 and 0.4 for the two farms. The virus was confirmed both by IFAT and by partial sequencing of the G gene. Phylogenetic analysis revealed that the Kenyan isolates were identical to those of the J genogroup found mostly in Asia. The findings have implications for biosecurity measures and import regulations for the Kenyan rainbow trout industry. 相似文献
4.
Christiana Eleojo Aruwa Charlene Pillay Martin M.Nyaga Saheed Sabiu 《畜牧与生物技术杂志(英文版)》2022,(2):338-352
The gastrointestinal tract(GIT)health impacts animal productivity.The poultry microbiome has functions which range from protection against pathogens and nutrients production,to host immune system maturation.Fluctuations in the microbiome have also been linked to prevailing environmental conditions.Healthy poultry birds possess a natural resistance to infection.However,the exploration of environmental impacts and other relevant factors on poultry growth and health have been underplayed.Since good performance and growth rate are central to animal production,the host-microbiome relationship remains integral.Prior to the emergence of metagenomic techniques,conventional methods for poultry microbiome studies were used and were low-throughput and associated with insufficient genomic data and high cost of sequencing.Fortunately,the advent of high-throughput sequencing platforms have circumvented some of these shortfalls and paved the way for increased studies on the poultry gut microbiome diversity and functions.Here,we give an up-to-date review on the impact of varied environments on microbiome profile,as well as microbiome engineering and microbiome technology advancements.It is hoped that this paper will provide invaluable information that could guide and inspire further studies on the lingering pertinent questions about the poultry microbiome. 相似文献
5.
Duncan M. Mwangi William K. Munyua P. N. Nyaga 《Tropical animal health and production》1990,22(2):95-100
Trypanosoma congolense infected goats were vaccinated with Bacillus anthracis spore vaccine to determine the effect of such infection on the humoral immune response to the vaccine. The anti-anthrax antibody levels were severely depressed in infected goats. When trypanocidal therapy was administered to T. congolense infected goats 14 days after infection they developed antibody levels against Bacillus anthracis similar to uninfected controls. 相似文献
6.
Viral nucleoprotein localization and lesions of Newcastle disease in tissues of indigenous ducks 总被引：1，自引：0，他引：1
Njagi LW Mbuthia PG Nyaga PN Bebora LC Minga UM 《Tropical animal health and production》2012,44(4):747-750
Localization of Newcastle disease viral nucleoprotein and pathological lesions was evaluated in tissues of 55 indigenous ducks
(45 experimentally infected and 10 sentinel ones). In addition, ten Newcastle disease infected chickens were used to ensure
that the virus inoculum administered to the ducks produced the disease in chickens, the susceptible hosts. Ducks were killed
on day 1, 4, 8 and 14 post-infection. Post-mortem examination was done with six tissues (liver, spleen, lung, caecal tonsils,
kidneys and brain) being collected from each bird. The tissues were preserved in 10% neutral formalin for 24 h. They were
then transferred to 70% ethanol for histology and immunohistochemical staining. Airsacculitis, necrotic splenic foci, congested
intestines, lymphoid depleted caecal tonsils and focal infiltrations by mononuclear cells were the main pathological lesions
in infected ducks. Over 28.9% of the infected ducks had Newcastle disease viral nucleoprotein in macrophage-like large mononuclear
cells in the caecal tonsils and kidney tubular epithelium. The viral antigens were located in the cytoplasm and nucleolus
of the cells. The other organs had no detectable viral antigens. This study shows that the kidneys and caecal tonsils are
the likely predilection sites for the virus in ducks. They thus need to be considered as diagnostic indicators for the viral
carriage in ducks. 相似文献
7.
Infectious pancreatic necrosis virus isolated from farmed rainbow trout and tilapia in Kenya is identical to European isolates 
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下载免费PDF全文 I R Mulei P N Nyaga P G Mbuthia R M Waruiru L W Njagi E W Mwihia A.A.A. Gamil Ø Evensen S Mutoloki 《Journal of fish diseases》2018,41(8):1191-1200
Infectious pancreatic necrosis virus (IPNV) is an aquabirnavirus that causes serious diseases in a variety of fish species worldwide. It has been isolated from a large number of healthy fresh and marine water fish. Prior to this study, there was no record of the presence of IPNV infection in Kenya. Here, the presence of IPNV in farmed rainbow trout and tilapia was examined in Nyeri County of central Kenya. Head kidney samples taken from five rainbow trout and three tilapia farms and stored in RNALater® were processed by PCR followed by sequencing of a segment A fragment covering nucleotide positions 2,120–2,343 bp. IPNV was detected in all the farms sampled with infection ratios ranging from 0.3 to 0.78 although the infections were not associated with any specific clinical signs of disease. These findings were supported by immunohistochemistry staining of the virus in the kidney and exocrine pancreas of rainbow trout. Sequence alignment and phylogenetic analysis revealed that the Kenyan isolates were identical to European isolates, suggesting a common origin. These findings highlight the need for better biosecurity procedures with more stringent surveillance programmes and control for fish diseases, especially focusing on imported breeding materials to Kenya. 相似文献
8.
Panshin A Shihmanter E Weisman Y Orvell C Kydyrmanov A Sayatov M Asanov N Nyaga PN Kasiiti JL Macharia MJ Lipkind M 《Comparative immunology, microbiology and infectious diseases》2001,24(1):21-37
Twenty six Newcastle disease viruses--12 reference strains and 14 strains isolated in Kenya and Kazakhstan--were characterized by means of a large panel of 38 monoclonal antibodies (MAB) directed against all the three envelope proteins: matrix, hemagglutinin-neuraminidase and fusion. The essential distinctions were revealed between the viruses isolated in Kenya and Kazakhstan while the differences amongst the viruses belonging to the same local group were much smaller. The heterogeneity amongst the viruses isolated in Kenya was more expressed as compared to the Kazakhstanian strains. 相似文献
9.
Namu John Alakonya Amos Karuri Hannah Nyaga Justin Masanga Joel Njeri Editah 《Journal of Crop Science and Biotechnology》2019,22(1):47-54
Journal of Crop Science and Biotechnology - Meloidogyne incognita causes huge yield losses in rice which is the third most important cereal crop in Kenya. The aim of this study was to identify M.... 相似文献
10.
J S Kaminjolo P N Nyaga J K Omuse E R Mutiga 《American journal of veterinary research》1975,36(1):123-125
Infectious bovine rhinotracheitis-infectious pustular vulvovaginitis (IBR-IPV) viral isolates were obtained from cattle affected with epididymitis-vaginitis. Isolation of virus from the diseased animals indicated that the genital form of IBR-IPV virus infection exists in Kenya and that epididymitis-vaginitis may be associated with IBR-IPV virus. Serums prepared from cattle having the genital form of the disease did not always have detectable antibody titers. 相似文献