250 research outputs found
Einfluss von Haltung und Management auf Ferkelverluste in einer freien Abferkelbucht
Projektvorstellung:
Videoaufzeichnungen im Ferkelnest (während der ersten 72 Stunden nach der Abferkelung), in der Bucht (während der Abferkelung und den 72 folgenden Stunden) und im Auslauf (während der ersten zehn Tage nach der Abferkelung)
Zusätzliche Erfassung von allgemeinen Leistungsparametern der Tiere (u.a. Ferkelanzahl, Lebendmasse wöchentlich, medizinische Behandlungen), Temperaturen innerhalb und außerhalb des Stalls sowie ökonomischen Kennzahlen
Auswertung der Videos unter Verwendung von Behavioral Observation Research Interactive Software (BORIS).
Zielsetzung:
Optimierte Frequentierung des Ferkelnests zur Reduktion früher Saugferkelverluste;
Überprüfung der Buchtengestaltung und eine eventuelle Früherkennung von Problemgeburten oder von gesundheitlichen Problemen der Sauen nach der Geburt;
Untersuchung der Auslaufnutzung im Hinblick auf Tierwohl und Tiergesundhei
Behavioural observations of sows and piglets in an organic free far-rowing pen with a focus on the piglet nest
Piglet losses in the early suckling period, in particular due to crushing by the sow, must be kept as low as possible. A prolonged stay in the piglet nest can improve the probability of piglet survival because there is a reduced risk of hypothermia and crushing or kicking by the sow. Different piglet nest designs and management strategies will be compared to find the condi-tions under which piglets are most likely to be in the nest: electric lid heating vs. underfloor heating, with vs. without LED-light, and with vs. without confinement in the piglet nest during the first feeding times of the sow after farrowing, resulting in eight combinations of treatments. To evaluate the whereabouts and behaviour of the animals, video cameras in the piglet nest, the pen and the outdoor run will record the first 72 hours after farrowing
Combined pasture and housing systems in Germany: year-round outdoor housing for pregnant sows
This organic farm is a best practice example in Germany of the combination of indoor and outdoor housing throughout the breeding cycle. This publication presents pasture management and costs as well as the Core Organic Cofund project POWER’s assessment of productivity, animal welfare and environmental impact of this farm
Erste Ergebnisse eines Grundfuttervergleichs zur Senkung der Skatolbelastung in der ökologischen Ebermast
Skatole, one of the main causes of boar taint, derives from tryptophan in the large intestine and accumulates in the fat tissue of boars, thus decreasing meat quality. We hypothesize that energy of roughage promotes growth of skatole reducing microbes. Therefore, we compare the two roughages grass-clover-silage and straw, regarding the effect on concentrations of skatole and androstenone in the fat tissue. The experiments are currently ongoing and will help to evaluate special feeding strategies as an alternative to castration, thereby promoting animal welfare and product quality
Oncolytic measles viruses to support BiTE and CAR T cell re-direction immunotherapies of solid tumors
Bispecific T cell engagers (BiTEs), artificial antibodies designed to cross-link T cells to tumor
cells, and chimeric antigen receptors (CARs), expressed on the surface of modified T cells and
transferring activating signals via intracellular domains, can re-direct T cells to tumor surface
antigens for efficient treatment of hematological malignancies. In solid tumors, however, these
novel immunotherapies face fundamental challenges: Physical exclusion of T cells and an immunosuppressive
microenvironment prevent efficacy while systemic administration is associated with
severe toxicities. Oncolytic viruses have emerged as ideal agents for combination immunotherapies,
as lytic replication in tumors does not only induce tumor debulking, but also immunogenic cancer
cell death and local inflammation. We therefore hypothesized that oncolytic virotherapy, by
eliminating physical barriers and reversing local immunosuppression, can promote anti-tumor T
cell responses and thus provide a potent treatment option for solid tumors in combination with T
cell re-direction. We furthermore hypothesized that tumor-targeted expression of a virus-encoded
BiTE could achieve local BiTE activity without systemic side effects.
To test these hypotheses, we engineered oncolytic measles viruses (MV) encoding BiTEs targeting
CD20 or carcinoembryonic antigen, respectively, as model antigens (MV-BiTE). Kinetics of viral
replication and virus-mediated cytotoxicity showed minor differences compared to unmodified
virus, and functional BiTEs could be obtained from the supernatant of virus-infected cells.
A newly established syngeneic solid tumor model of B16-CD20-CD46 murine melanoma cells
stably expressing human antigens CD20 and CD46 as BiTE target antigen and measles virus
entry receptor, respectively, engrafted in immunocompetent C57BL/6 mice when implanted
subcutaneously. In this model, treatment with MV-BiTE targeting CD20 significantly prolonged
survival compared to control treatments with unmodified MV, MV encoding CEA-specific control
BiTE, purified BiTE, or carrier fluid only, respectively. UV irradiation of MV-BiTE completely
inhibited viral replication but did not abrogate efficacy in this model. Treatment efficacy was
furthermore not impaired in mice previously immunized with MV. Increased T cell infiltration
into tumors and an effector T cell phenotype characterized by high intratumoral CD8+ T cell
levels and low relative abundance of regulatory T cells was observed upon MV-BiTE treatment.
Targeted transcriptome analysis revealed upregulation of genes associated with T cell activation,
proliferation, and differentiation, but also with inhibition and exhaustion, providing a rationale
for combination with checkpoint inhibitors.
Combinations of MV, BiTE, and CAR T cell therapies were investigated in a pancreatic cancer
model. Cytotoxic potential of each treatment alone towards human pancreatic adenocarcinoma
cells was observed in vitro. However, no significant benefit of combinations was observed in a
pilot experiment in immunodeficient mice, and T cell persistence was limited. For future in vivo
monitoring of T cells by magnetic resonance imaging, labeling with iron oxide nanoparticles was
established. In addition, we describe a mathematical model for in silico predictions of treatment
outcome to optimize scheduling of combination therapies.
Taken together, this study shows for the first time efficacy of a BiTE-encoding oncolytic virus in an
immunocompetent mouse model. This warrants further investigations towards future translation.
We furthermore introduced a mathematical model of combination immunovirotherapy to further
support the development of novel treatment options for cancer patients
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