Livestock Fish Flagship: Animal Health

Permanent URI for this collectionhttps://hdl.handle.net/10568/16627

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Role of the polymorphic immunodominant molecule in entry of Theileria parva sporozoites into bovine lymphocytes
(Journal Article, 2014-05) Toye, Philip G.; Musoke, A.J.; Naessens, Jan
Theileria parva is a tick-transmitted apicomplexan parasite that infects cattle and African buffalo. In cattle, it causes a fatal lymphoproliferative disease called East Coast fever. The polymorphic immunodominant molecule (PIM) is expressed by two stages of the parasite: the sporozoite, which is inoculated by the tick to infect mammalian lymphocytes, and the schizont, the established intralymphocytic stage. Here, we demonstrate that monoclonal antibodies (MAb) to PIM can reduce the ability of sporozoites to infect bovine lymphocytes in vitro. This reduction appears to be due to blocking of sporozoite attachment by binding of the MAb to several regions of PIM. Interestingly, one MAb, which recognizes an epitope in the central variable region of PIM, did not inhibit sporozoite infectivity. We also demonstrate that PIM antigen, as a recombinant molecule, can also reduce sporozoite infectivity in vitro by blocking both attachment and internalization of sporozoites. Electron microscopic studies showed that PIM is present in microspheres below the sporozoite surface and is transported to the parasite surface soon after contact with bovine lymphocytes. The results suggest that at least two sporozoite molecules, PIM and the previously described p67, are involved in the entry of T. parva into mammalian lymphocytes.
An assessment of chemical and biological product use in aquaculture in Bangladesh
(Journal Article, 2016-03) Ali, H.; Rico, A.; Murshed-e-Jahan, K.; Belton, Ben
The aim of this study is to describe current chemical use practices in the aquaculture sector of Bangladesh and to identify the factors that influence them. A survey on the use of chemical and biological products was conducted between November 2011 and June 2012 using structured questionnaires administered to operators of nine farm groups, including homestead ponds, carps, tilapias, koi fish, shrimps, shrimps and prawns, prawns, rice and fish, and pangas. Farm type and farm owner characteristics were used as independent variables to explain observed chemical use. Forty-six chemical and biological products (7 water and sediment treatment compounds, 13 disinfectants, 7 antibiotics, 7 pesticides, 8 fertilizers and 4 feed additives and probiotics) were reported to be applied in aquaculture. The use of disinfectants and antibiotics was found to be highest in intensive koi and pangas farms as compared to other farm groups, whereas the use of fertilizers was lowest in these farm groups. A higher percentage of prawn and shrimp/prawn farmers applied pesticides than other farm groups. A multivariate analysis showed that patterns of use of chemical and biological products were significantly different across aquaculture farm groups, with the largest number of chemical compounds used by the intensive koi farm group. The study shows that, despite rapid expansion of commercial aquaculture in Bangladesh, use of chemical and biological products is still relatively low compared to other aquaculture producing countries in Asia. However, despite this finding, the study identified a large number of compounds that are currently in use, and that require further regulation and evaluation regarding their potential environmental and human health impacts, as already done in most developed countries.
PmPPAF is a pro-phenoloxidase activating factor involved in innate immunity response of the shrimp Penaeus monodon
(Journal Article, 2014-05) Ma, T.H.T.; Benzie, John A.H.; Jian-Guo He; Cheng-Bo Sun; Siuming F. Chan
One of the major steps in the innate immune response of shrimp includes the activation of serine proteinases of the pro-phenoloxidase pathway by the prophenoloxidase activation enzyme (PPAF). In this study, the cDNA encoding a serine proteinase homologue (SPH) with prophenoloxidase activating activity of Penaeus monodon (PmPPAF) was cloned and characterized. PmPPAF cDNA consists of 1444 nucleotides encoding a protein with 394 amino acid residues. The estimated molecular weight of PmPPAF is 43.5 kDa with an isoelectric point of 5.19. PmPPAF consists of a signal peptide, a CLIP domain and a carboxyl-terminal trypsin-like serine protease domain. It is highly similar to the masquerade-like protein 2A (61% similarity) of the crayfish Pacifastacus leniusculus, other serine proteases (42.9–67% identity) of P. monodon, and the PPAF of the crab (61% similarity). Unlike other SPH of P. monodon, which express mainly in the hemocytes, PmPPAF transcripts were detected in the hemocytes, eyestalk, hypodermis, gill, swimming leg and brain. Similar to the crab PPAF, PmPPAF transcript level is high in shrimp at the premolt stages and PmPPAF expression is up-regulated in shrimp infected with white spot syndrome virus (WSSV). Gene silencing of PmPPAF decreased expression of a prophenoloxidase-like gene and injection of Anti-PmPPAF antibody causes a decrease in PO activity. Taken together, these results provided evidence that PmPPAF is a serine proteinase homologue, and is involved in the pro-PO activation pathway of the shrimp innate immune system.
Risk factors for African swine fever in smallholder pig production systems in Uganda
(Journal Article, 2017-06) Dione, Michel M.; Akol, Joyce; Roesel, Kristina; Kungu, J.; Ouma, Emily A.; Wieland, Barbara; Pezo, Danilo A.
Smallholder pig production in Uganda is constrained by poor management and high disease burden, with African swine fever (ASF) being one of the most important contributors. However, data to develop appropriate evidence-based disease mitigating interventions along the pig value chain are lacking. This study aimed at determining risk factors associated with the occurrence of outbreaks of ASF in selected districts. A cross-sectional survey of 1195 pig-keeping households in three districts was carried out between April and July 2013. Households were classified into one of three value chain domains (VCDs) based on where the production was located and where most of the products were sold: rural-rural (R-R), rural-urban (R-U) and urban-urban (U-U). Findings revealed that crop farming is the most common primary activity in the R-R and R-U VCDs, while pig keeping was the most common primary activity in the U-U VCDs. Pigs are mostly kept tethered or left to roam in the R-R and R-U VCDs, while in the U-U VCDs, they are mostly confined in corrals. Nearly 20% of the farmers whose farms were hit by an ASF outbreak subsequently sold all their pigs (healthy and sick) to the market in panic. Factors that positively correlated with recent ASF outbreaks were prompt disposal of dead pigs on farms (P < 0.001, OR = 2.3), wild animals present in the village (P < 0.001, OR = 1.7) and farmers sourcing drugs from stockists (P < 0.001, OR = 1.6); while protective factors were the presence of perimeter fences (P = 0.03, OR = 0.5), attendance of farmers at secondary-school level and above (P < 0.001, OR = 0.6), routine cleaning of the pig pens (P < 0.001, OR = 0.6) and pigs being the only livestock kept by farmer (P = 0.01, OR = 0.7). Given the current situation, there is a need to raise awareness among farmers and other value chain actors of biosecurity measures and create incentives for farmers to report ASF cases.
Understanding the dynamics and spread of African Swine fever at the wildlife livestock interface: Insights into the potential role of the bushpig Potamochoerus larvatus
(Journal Article, 2014-06-15) Stahl, K.; Ogweng, P.; Okoth, Edward A.; Aliro, T.; Muhangi, D.; LeBlanc, N.; Atimnedi, P.; Berg, M.; Bishop, Richard P.; Rasmussen, H.B.; Masembe, C.
Improved vaccines for the control of ECF in cattle in Africa: Notes from the ECF Consortium Workshop, Addis Ababa, 9-11 February 2015.
(Report, 2015-02-09) Ballantyne, Peter G.; Nene, Vishvanath M.
Identification of MHCI-associated peptides using LC-MS/MS
(Presentation, 2015-02-09) Ternette, Nicola
Use of heat shock proteins for induction of CTL immunity
(Presentation, 2015-02-09) Muthoni, C.; Nzau, Benjamin M.; Pelle, Roger
CTL-induction, adjuvants and reagents
(Presentation, 2015-02-09) Steinaa, Lucilla
Yeast expression systems and RVC activities
(Presentation, 2015-02-09) Goh, S.; Werling, D.
Bovine Herpesvirus-4 as a delivery platform for Theileria parva antigens
(Presentation, 2015-02-09) Williams, Laura B.; Morrison, W. Ivan; MacHugh, Niall D.; Brown, Wendy; Fry, Lindsay M.; Knowles, Donald P.; Donofrio, Gaetano
Evaluating the Ad5/MVA antigen delivery systems
(Presentation, 2015-02-09) Svitek, Nicholas; Saya, R.; Awino, Elias; Munyao, S.; Njoroge, T.; Gilbert, S.; Nene, Vishvanath M.; Steinaa, Lucilla
Determining requirements for induction and recall of an effective CD8 T cell response
(Presentation, 2015-02-09) Morrison, W. Ivan
Identifying new schizont antigens recognised by parasite-specific T cells from immune cattle
(Presentation, 2015-02-09) Morrison, W. Ivan
Selection of T. parva CD4+ T-cell Candidate Antigens and T. parva Immunopathogy
(Presentation, 2015-02-09) Fry, Lindsay M.; Knowles, Donald P.; Nelson, D.; Morrison, W. Ivan; Connelley, T.; Silva, Joana C.; Scoles, Glen A.; Olds, Cassandra L.; Brown, L.
Development of a Tick Challenge Model
(Presentation, 2015-02-09) Olds, Cassandra L.; Fry, Lindsay M.; Knowles, Donald P.; Brown, Wendy
Characterizing the magnitude, kinetics and functional profile of the protective T-cell response and evaluate Ad5/MVA antigen delivery systems
(Presentation, 2015-02-09) Connelley, T.
PIM immunization studies
(Presentation, 2015-02-09) Goeyse, I. de
ITM Process Improvement at CTTBD, Lilongwe
(Presentation, 2015-02-09) Kalenzi, D.
Genome re-annotation and identification of putative antigens: 2014 brief review
(Presentation, 2015-02-09) Silva, Joana C.; Tretina, Kyle; Orvis, J.; Gotia, T.; Pelle, Roger; Abolude, K.; Kumari, P.; Iqbal, S.; Bishop, Richard P.; Daubenberger, C.A.

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