A Multicenter, Randomized Field Trial on the Efficacy and Safety of VEPURED®, A New Vaccine Against Edema Disease in Pigs
Eva Perozo,
Joaquim Mallorquí,
Ainhoa Puig,
David Sabaté,
Laura Ferrer-Soler,
Ricard March
Issue:
Volume 6, Issue 6, November 2018
Pages:
95-101
Received:
11 December 2018
Accepted:
2 January 2019
Published:
31 January 2019
DOI:
10.11648/j.avs.20180606.11
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Abstract: The aim of this study was to evaluate under field conditions the efficacy and safety of Vepured, a new recombinant vaccine against Edema Disease in pigs. The study was conducted on five commercial farrow-to-finish pig farms, which had historical records of clinical signs and presented F18-positive E.coli producing VT2e. The study was designed as a multicenter, randomized, placebo-controlled, blinded field trial comparing Vepured vaccine to a placebo (phosphate-buffered saline). Animals, at the age of 2-3 days, were administered intramuscularly with 1mL of Vepured (n=945) or with 1mL of phosphate-buffered saline (n=824). After product administration, animals were followed-up until slaughter. During this period, several efficacy and safety parameters were evaluated. On each farm, animals from both groups were held in the same unit and subjected to the same husbandry practices throughout the study. Clinical outbreaks of edema disease were only reported on four farms. On these farms, vaccination with Vepured resulted in a statistically significant reduction in both the mortality rate and the occurrence of clinical signs related to the disease. A statistically significantly higher mean growth performance was also reported in the vaccinated group compared to the placebo group. In the farm without clinical outbreak of edema disease differences were also observed in growth performance in favor of the vaccinated group. No systemic reactions were observed during or immediately after vaccination with Vepured. Only mild transient local reactions, and slight clinically non-relevant temperature increases were reported in some animals. The results obtained in this study demonstrate that vaccination with Vepured is safe and efficacious against naturally occurring edema disease infection.
Abstract: The aim of this study was to evaluate under field conditions the efficacy and safety of Vepured, a new recombinant vaccine against Edema Disease in pigs. The study was conducted on five commercial farrow-to-finish pig farms, which had historical records of clinical signs and presented F18-positive E.coli producing VT2e. The study was designed as a ...
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Potential of Water Extracts from Reticulitermes Flavipes on Control of Solenopsis Gayi
Joaquín Ipinza-Regla,
Alejandra Olivares,
Jaime Eduardo Araya
Issue:
Volume 6, Issue 6, November 2018
Pages:
102-106
Received:
4 September 2018
Accepted:
11 October 2018
Published:
15 March 2019
DOI:
10.11648/j.avs.20180606.12
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Abstract: Five nests each of Reticulitermes flavipes Kollar (Isoptera: Rhinotermitidae) and Solenopsis gayi Spinola (Hymenoptera: Formicidae) were collected in sites distanced at least 1 km in the Metropolitan Region, Santiago, Chile, to study the modification of hermeticism conducts of termites exposed to ant specimens on transparent plastic arenas lined with filter paper sprayed or bathed with a water extract of the termite, obtained by setting 20 of them on test tubes that were frozen, added acetone, and stirred in a vortex mixer. Finally the termites were eliminated and the acetone evaporated with gaseous nitrogen. Then, the extracts were dissolved in H2O. A control group was used per nest. The behavior of S. gayi receiving R. flavipes treated or untreated was observed during 6 min, registering antennal exploration (AE), mandible opening (MO), biting (BI), abdomen flexed dorsally or ventrally (AFD and AFV, respectively), fighting (FI), backward movement (BM), transport of intruder (TI), and death (DE). The behavior of R. flavipes receiving treated or untreated termites was also observed during 6 min, registering the approach to the intruder and brief pursuit by one or more termites (API), mandible opening (MO), and biting (BI). The transference of ants treated to their original nests increased the frequency of recognition events (AE and MO), as well as BI, which occurred earlier, compared with control groups. In contrast, when treated ants were transferred to receiving termites, a decreased frequency and a delayed appearance occurred in API and MO. Intruder death (DE) did not occur in both transference bioassays. In summary, S. gayi treated were recognized as intruders and rejected by the ants of their nests. In contrast, the recipient R. flavipes termites recognized the extract-treated ants as members of their nests.
Abstract: Five nests each of Reticulitermes flavipes Kollar (Isoptera: Rhinotermitidae) and Solenopsis gayi Spinola (Hymenoptera: Formicidae) were collected in sites distanced at least 1 km in the Metropolitan Region, Santiago, Chile, to study the modification of hermeticism conducts of termites exposed to ant specimens on transparent plastic arenas lined wi...
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