Clinical Evaluation and Preventative Care in Donkeys.

Clinical evaluation and preventative care in donkeys should follow similar guidelines as for horses. There are species-specific differences due to the desert-adapted physiology of the donkey. Donkeys are mainly used as pack animals, companions and for production of meat or milk - they may be kept well into old age.

Respiratory Disorders of the Donkey.

Donkeys suffer from the same respiratory diseases as horses; however, owing to their nonathletic nature many conditions can present in a more advanced state before becoming clinically apparent. Anatomically, their respiratory tract is similar to the horse, with certain species-specific differences that are important to be aware of. Often donkeys do not receive the same level of routine care as horses, so many are not vaccinated against respiratory pathogens such as influenza or herpesviruses.

Modulation of equine neutrophil adherence and migration by the annexin-1 derived N-terminal peptide, Ac2-26.

Neutrophil activation, whilst a key component of host defence, must be tightly regulated in order to avoid an inappropriate cellular response. Annexin-1, which is present in large amounts in neutrophils, and its N-terminal peptides, reduce neutrophil accumulation but annexin peptides have also been shown to exhibit neutrophil activating properties. We have recently shown annexin-1 to be present in equine neutrophils and demonstrated that the annexin-1-derived peptide, Ac2-26, can both reduce superoxide production by these cells in response to other stimuli and directly induce free radical production at a higher concentration.

CXCL8 attenuates chemoattractant-induced equine neutrophil migration.

The chemokine, CXCL8, is a potent chemoattractant but it has also been shown to attenuate the migratory response of human neutrophils to the bacterial peptide, FMLP; this could lead to retention of cells in infected tissue and, potentially, to enhanced clearance of bacteria. This study has examined the effect of CXCL8 on equine neutrophil migration and adherence in response to PAF and LTB(4), chemoattractants that may play a role in non-infectious inflammatory conditions of the horse associated with neutrophil recruitment to the target tissue. The effects of CXCL8 on PAF- and LTB(4)-induced responses were determined using a ChemoTx plate migration assay and by measuring adhesion to protein-coated plastic.

Validating 123I-metaiodobenzylguanidine as a platelet marker for non-invasive imaging in rabbits.

Introduction: Recent in vitro studies in our laboratory have demonstrated that platelets are necessary for leukocyte recruitment and airway remodelling in models of allergic airway inflammation, and also migrate to lung tissues in response to anti-IgE or relevant allergens in allergic asthma. Non-invasive imaging of platelet migration in vivo would provide a further insight into the roles of platelets in inflammatory diseases such as asthma, and metaiodobenzylguanidine (MIBG) was considered as a suitable platelet marker.

Methods: The kinetics of MIBG uptake into rabbit platelets, the effect of MIBG on platelet function and the effect of platelet activation on MIBG uptake and retention were investigated.

Evaluation of the effect of phosphodiesterase on equine platelet activation and the effect of antigen challenge on platelet phosphodiesterase activity in horses with recurrent airway obstruction.

Objective: To determine whether expression of equine platelet activation-dependent surface markers is influenced by phospodiesterase (PDE) isoenzyme activity and whether antigen challenge alters platelet PDE activity in horses with recurrent airway obstruction (RAO).

Animals: 16 horses.

Procedures: 7 healthy horses were used for in vitro experiments, 6 horses with RAO were used for antigen challenge, and 6 healthy horses were used as control animals.

Expression of annexin-1 in equine leucocytes and the effects of the N-terminal annexin-1 peptide, Ac2-26, on equine neutrophil superoxide production.

N-terminal peptides derived from the anti-inflammatory peptide, annexin-1, inhibit neutrophil function but can also induce pro-inflammatory effects. Although equine annexin-1 has been sequenced, its cellular expression and properties have not been reported. This study has examined whether annexin-1 is present in equine leucocytes and how the N-terminal peptide, Ac2-26, affects equine neutrophil superoxide production.

Phosphodiesterase isoenzymes in equine platelets and their influence on platelet adhesion.

Objective: To determine the phosphodiesterase (PDE) isoenzymes in equine platelets and evaluate their influence on platelet adhesion.

Sample Population: Platelets obtained from healthy New Forest Pony geldings that ranged from 12 to 20 years of age (mean +/- SEM, 17.3 +/- 1.