Respiratory airflow patterns in ponies at rest and during exercise.

The exercise-induced changes in the equine breathing pattern were studied by analyzing tidal breathing flow-volume loops recorded in ten ponies both at rest and during a standardized exercise. Airflow, tidal volume, esophageal pressure and mask pressure were simultaneously recorded before, during and after a treadmill exercise. From the collected data, respiratory frequency and total pulmonary resistance were calculated, tidal breathing flow-volume loops were retraced using a computerized method and loop indices were measured for each period of the experimental protocol. For each pony, results of three consecutive daily measurements were averaged. The exercise loop indices were compared with the corresponding resting values using a one-way analysis of variance. The significantly changed indices were correlated with respiratory frequency and total pulmonary resistance. Several types of respiratory patterns were observed at rest as well as during exercise, although each pony was relatively constant in its own pattern of breathing. Most resting inspiratory and expiratory airflow curves were found to be biphasic. When ponies started running, the airflow developed an increasingly rectangular pattern. During strenuous exercise, both inspiratory and expiratory airflow curves showed a substantial increase of the volume acceleration and tended to a plateau. The loop indices relating the expiratory to the inspiratory airflow were significantly increased compared with their rest values. Correlations of these indices with respiratory frequency and total pulmonary resistance were weak.(ABSTRACT TRUNCATED AT 250 WORDS

Investigation of nursing strategies to improve adaptation to extra-uterine life in Belgian White and Blue calves and Holstein calves during the first 24 hours after birth.

peer reviewe

Respiratory syncytial virus pneumonia in Friesian calves : physiological findings

Clinical, serological and physiological values were measured during and after naturally occurring respiratory syncytial virus pneumonia in four Friesian calves weighing between 120 and 160 kg. Clinical and serological findings were in agreement with the description of spontaneous calf pneumonia, associated with respiratory syncytial virus infection. Pulmonary function values, recorded one, eight, 15 and 57 days after the clinical onset of the disease, provided good evidence that the clinical syndrome associated with respiratory syncytial virus infection in Friesian cattle is at first an acute obstructive disease which is progressively replaced by a moderate subclinical restrictive disease

Plasma Beta-Endorphin Response of Thoroughbred Horses to Maximal Exercise

Ten horses underwent a standardised strenuous treadmill exercise test, before, during and after which measurements were made of plasma beta-endorphin and cortisol concentrations, blood lactate, glucose, haemoglobin and pH, the activities of creatine kinase, lactate dehydrogenase and aspartate amino-transferase, and heart rate, oxygen uptake and expired minute volume. The correlations between the exercise-induced response of beta-endorphin and the changes observed in the other physiological measurements were examined. There was a large variation in the beta-endorphin response of the horses to exercise. The increase in beta-endorphin was correlated significantly and inversely with the treadmill velocity at which maximal oxygen uptake was reached. It was also significantly and directly correlated with the heart rate during recovery, the increase in plasma lactate concentration and the change in blood pH, indicating that the exercise-induced increase in beta-endorphin concentration was smaller in horses with a higher aerobic capacit

Cytokine and anti-cytokine strategies in inflammatory reaction modulation

Evidence of the importance of a cytokine cascade in the induction and control of the inflammatory reaction is increasing. Although cytokines are required in the inflammatory process in response to infection or injury, their overproduction, particularly that of interleukin-1 (IL-1) and tumor necrosis factor (TNF), can lead to local/systemic pathology. Selective inhibition of the synthesis or of the action of specific cytokines may be of therapeutic benefit. Various strategies for blocking IL-1 and TNF activities have been presented. While selective inhibition of cytokine synthesis is still in the early experimental phase, specific blockade of soluble cytokine action following synthesis and release from cells is undergoing preliminary clinical trials in humans. Animal data suggest that antimonoclonal therapy such as monoclonal antibodies to TNF, IL-1 receptor antagonists or soluble receptors to TNF and IL-1 can be effective in the modulation of the inflammatory reaction. Modulation of the cytokine network in some diseases might also include the use of anti-inflammatory cytokines. Nonetheless, the possibilities of side effects due to impaired host-defense mechanisms with the IL-1 or TNF blockade must also be taken into consideration

Come migliorare la caduta di respirazione nel vitello appena nato attraverso un "nursing" appropriato.

peer reviewe

Intrathoracic pressure measurement in cattle: standardized procedure.

A procedure to standardize the position of an esophageal catheter (eso-cat) tip, used to measure intrathoracic pressure, was tested in ten healthy Dutch Friesians. The cattle were in normal condition with body weights (BW) between 52 and 670 kg and thoracic perimeters (TP) between 80 and 210 cm. The position of the neck and head was standardized. The eso-cat was introduced via the nose into the thoracic portion of the esophagus. The distance between the nares and the eso-cat tip (Lcat), which was positioned between the crossing point with the aorta and the caudal mediastinal lymph nodes, was measured for each animal. The regression equation, calculated between the Lcat and the BW and TP was, respectively: Lcat (cm) = 65 + 0.115 x BW (kg) (r2 = 0.99) and Lcat (cm) = 22 + 0.535 x TP (cm) (r2 = 0.97). The corresponding residual standard deviations were respectively 2.52 and 4.37 cm. The multiple and curvi-linear regression equation did not give a significantly better fit of the data

Oxygen Transport Chain in Double-Muscled Blue Belgian Cattle

The physiological peculiarities of the oxygen transport chain in double-muscled Blue Belgian cattle are described. The investigations performed at several levels of the oxygen transport chain suggest that the increased susceptibility of these cattle to stress, resulting mainly in respiratory diseases, is due to an insufficient functional reserve capacity mainly involving the pulmonary and cardiovascular systems. The resulting lack of 'functional hardiness' of the oxygen transport chain is seen in those double-muscled cattle which do not react in an appropriate or predictable way when submitted to a hostile environment