12 research outputs found
Immune response of healthy horses to DNA constructs formulated with a cationic lipid transfection reagent
Background Deoxyribonucleic acid (DNA) vaccines are used for experimental
immunotherapy of equine melanoma. The injection of complexed linear DNA
encoding interleukin (IL)-12/IL-18 induced partial tumour remission in a
clinical study including 27 grey horses. To date, the detailed mechanism of
the anti-tumour effect of this treatment is unknown. Results In the present
study, the clinical and cellular responses of 24 healthy horses were monitored
over 72 h after simultaneous intradermal and intramuscular application of
equine IL-12/IL-18 DNA (complexed with a transfection reagent) or comparative
substances (transfection reagent only, nonsense DNA, nonsense DNA depleted of
CG). Although the strongest effect was observed in horses treated with
expressing DNA, horses in all groups treated with DNA showed systemic
responses. In these horses treated with DNA, rectal temperatures were elevated
after treatment and serum amyloid A increased. Total leukocyte and neutrophil
counts increased, while lymphocyte numbers decreased. The secretion of tumour
necrosis factor alpha (TNFα) and interferon gamma (IFNγ) from peripheral
mononuclear blood cells ex vivo increased after treatments with DNA, while
IL-10 secretion decreased. Horses treated with DNA had significantly higher
myeloid cell numbers and chemokine (C-X-C motif) ligand (CXCL)-10 expression
in skin samples at the intradermal injection sites compared to horses treated
with transfection reagent only, suggesting an inflammatory response to DNA
treatment. In horses treated with expressing DNA, however, local CXCL-10
expression was highest and immunohistochemistry revealed more intradermal
IL-12-positive cells when compared to the other treatment groups. In contrast
to non-grey horses, grey horses showed fewer effects of DNA treatments on
blood lymphocyte counts, TNFα secretion and myeloid cell infiltration in the
dermis. Conclusion Treatment with complexed linear DNA constructs induced an
inflammatory response independent of the coding sequence and of CG motif
content. Expressing IL-12/IL-18 DNA locally induces expression of the
downstream mediator CXCL-10. The grey horses included appeared to display an
attenuated immune response to DNA treatment, although grey horses bearing
melanoma responded to this treatment with moderate tumour remission in a
preceding study. Whether the different immunological reactivity compared to
other horses may contributes to the melanoma susceptibility of grey horses
remains to be elucidated
Immune response of healthy horses to DNA constructs formulated with a cationic lipid transfection reagent
Effects of Overcheck Use on Stress Parameters and Welfare Implications in Driving Horses
Environmental Justice and American Indian Tribal Sovereignty: Case Study of a Land–Use Conflict in Skull Valley, Utah
Gordura corporal e eficiência reprodutiva em éguas doadoras de embrião Mangalarga Marchador Body fat and reproductive efficiency of Mangalarga Marchador embryo donor mares
Foi comparado o julgamento do escore de condição corporal (ECC) com a espessura de gordura subcutânea (EGS) e sua relação com a eficiência reprodutiva de éguas Mangalarga Marchador doadoras de embrião. O experimento foi conduzido com 56 éguas doadoras entre os meses de agosto/08 e abril/09. O ECC foi maior em éguas mais velhas e aumentou com os dias de permanência no experimento. Houve correlação positiva entre peso e tempo de experimento. O peso não foi associado à idade, porém aumentou ao longo do experimento. A EGS na região da cauda e entre a 12ª e 13ª costelas aumentou com a idade e diminuiu com os dias de permanência no experimento. Houve correlação positiva entre EGS e ECC para a cauda e costela. O diâmetro do folículo dominante aumentou ao longo do ciclo estral, e foi menor em éguas com ECC abaixo de 6,5. O diâmetro folicular não foi influenciado pela idade. O diâmetro médio do folículo ovulatório foi 38,43 ± 3,09 mm. A recuperação embrionária não foi afetada pela idade ou ECC, mas foi menor (41%) eméguas que ovularam folículos menores que 40 mm quando comparados às que ovularam folículos maiores que 40 mm (59%). A idade da doadora não foi associada à taxa de gestação dos embriões nas receptoras. A gordura corporal afetou a eficiência reprodutiva das éguas, além disso, a ultrassonografia parece ser essencial para a avaliação precisa e correta do escore de condição corporal.<br>Body condition scoring (BCS) was compared to an ultrasound subcutaneous fat thickness (SFT) determination in relation to the reproductive efficiency of Mangalarga Marchador embryo donor mares. Fifty six barren mares were studied throughout the 2008/2009 breeding season (August through April) and the experiment was designed in a completely randomized scheme. BCS was higher in older mares and increased with time in the experiment, and there was a positive interaction between weight and time. Weight was not associated with age, but increased throughout the experiment. Tail and rib BCS increased with age, and decreased with time. There was a positive correlation between BCS and tail and rib SFT. The diameter of the dominant follicle increased during the estrous cycle and was smaller for mares with BCS below 6.5. Age did not influence the dominant follicle diameter. The mean ovulatory follicle diameter was 38.43 ± 3.09. Embryo recovery was not affected by age or BCS but was lower (41%, P=0.003) in mares that ovulated follicles smaller than 40mm compared to mares ovulating follicles greater than 40mm (59%). Donor age was not associated with recipient pregnancy rates. Body fat affected the reproductive efficiency in mares, and seems that ultra-sonography may be essential for correct and reliable body condition scoring