OROPHARYNGEAE DYSPHAGIAS IN THE DOG: A CINEFLUOROGRAPHIC ANALYSIS OF EXPERIMENTALLY INDUCED AND SPONTANEOUSLY OCCURRING SWALLOWING DISORDERS

Cinefluorography and videoflurography were used to record and analyze the functional swallowing deficits of nine dogs with spontaneous oropharyngeal swallowing problems. Based on the clinical and radiographic signs observed in one dog with experimentally induced bilateral hypoglossal palsy and comparison with cinefluorograms of normal dogs, the nine spontaneous dysphagias were divided into five oral dysphagias and four pharyngeal dysphagias. Dogs with oral dysphagias had problems with tongue control and in prehending and transporting food and fluid to the oropharynx. On cinefluorograms, a poor closure of the oral egress led to the loss of contrast medium from the mouth, and a weak tongue-thrust action caused retention of contrast medium in the oropharynx. The clinical and radiographic signs could be duplicated by hypoglossal neurectomy. In contrast to the pharyngeal dysphagias, aspiration pneumonia was noticeably absent in oral dysphagias. The dogs with pharyngeal dysphagia had severe difficulties in transporting the food from the oropharynx to the laryngopharynx owing to a poor contractility of the pharyngeal muscles. The latter resulted in contrast medium retention in the pharynx and laryngotracheal aspiration. The need was stressed for a careful differentiation between oral and pharyngeal dysphagias on one hand, and cricopharyngeal dysphagias on the other hand. In oral dysphagias, cricopharyngeal myotomy appeared of no use. In pharyngeal dysphagias, cricopharyngeal myotomy severely aggravated the clinical signs by causing a cricopharyngeal chalasia.     

Nitrogen and phosphorus release from poultry manure composts: the role of carbonaceous bulking agents and compost particle sizes

Rice hulls and sawdust are commonly used to compost poultry manure in several countries. We studied the effects of these two bulking agents and different sizes of compost particles on the release of N and P from poultry manure composts. Five composts, produced with a 2:1 and 1:1 ratio of sawdust or rice hulls to poultry manure and 1:1:1 of all three materials, were separated into fractions >10, 5–10, 1–5, and <1 mm. The >10-mm fraction was less than 1.5% and was not further analyzed. In all other fractions, pH, electrical conductivity, organic C, lignin, cellulose, and total N, P, Ca, K, and Si were determined and related to N and P release in 16-week incubations of a sandy soil amended with 40 g kg⁻¹ of each fraction. Nitrogen release with composts containing sawdust was higher than with rice hull composts (114–189 vs. 78–127 mg kg⁻¹ at week 16), and this was highly correlated with TN (1.9–3.7% vs. 1.4–2.7%) and negatively with pH (5.5–6.2 vs. 6.7–6.9). Extractable P was very high (85–340 mg kg⁻¹ at week 16), and the highest values were associated with the composts with more proportion of poultry manure. An increase in stability with decreasing particle size was apparent from the gradient of N and P dynamics: from net P release and an exponential pattern of net N mineralization with the coarsest fraction to net P retention and a linear pattern of N mineralization with the smallest one. Despite its higher fertilizer value, the 5- to 10-mm fraction posed the highest environmental risk due to elevated P release over time.     

The Pharmacokineties of Alfentanil in Healthy Cats

Alfentanil (50 μg/kg) was administered intravenously, over 1 minute, to 6 healthy cats. Blood samples were collected from a preplaced arterial catheter at 0.625, 1.25, 2.5, 5, 10, 15, 20, 30, 45, 60, 90, 120, 180, 240, 360, and 480 minutes after the end of the alfentanil injection. A radio-immunoassay technique was used to measure alfentanil concentrations in plasma obtained from these samples. Arterial blood pressure was measured at 0.625, 1.25, 2.5, 5, 10, 15, 20, and 30 minutes and pH and blood gas measurements were carried out at 5, 10 and 30 minutes after the alfentanil. Analgesia, tested by placing a clamp on the base of the tail for 5 seconds, was assessed at each blood sampling time until analgesia was absent. The cats were observed for behavioural changes at each sample time. Alfentanil caused a transient increase in blood pressure and respiratory and metabolic acidosis. Following alfentanil all cats became excited and showed pupillary dilation. Analgesia was present for 21.7 ± 14 minutes. The plasma concentration-time data for 5 cats were best described by a 3 compartment open model with the curve fitting the equation: C_to= 162.6e^-0.2062t+ 60.le^-0.041t+ 13.2e^-0.0062t The harmonic means for the half lives of the rapid distribution, the slow distribution and the elimination phases were 4.12, 18.8, 119.2 minutes respectively.     

Normal Swallowing in the Dog: A Cineradiographic Study

Normal dog swallowing dynamics were analyzed and correlated with specific structures. There were oropharyngeal, esophageal, and gastroesophageal phases. The oropharyngeal phase was characterized by food prehension and bolus formation (oral stage), reflex pharyngeal peristalsis (pharyngeal stage), and reflex cricopharyngeal sphincter relaxation (cricopharyngeal stage). The esophageal phase was characterized by primary peristalsis initiated by the oropharyngeal phase and secondary peristalsis which occurred in response to mechanical stimuli from a bolus in the esophagus. There was a post-peristalsis refractory period during which new peristalsis would not occur. Repeated rapid swallowing would, therefore, result in accumulation of ingesta in the esophagus. The gastroesophageal phase occurred when a bolus passed through the gastroesophageal junction, an area which serves as a lower esophageal sphincter. Gastroesophageal reflux was observed as a normal, infrequent event followed by rapid esophageal clearance. Low doses of tranquilizers had no significant influence on swallowing function. The differences observed between sternal and lateral recumbent postures related only to the rate of food consumption which, in turn, influenced esophageal motor response and inhibited gastroesophageal closure. These differences did not adversely affect the autonomous phases of swallowing.     

Allergen-specific ELISA for horse IgE

An enzyme-linked immuno sorbent assay (ELISA) for measuring horse IgE specific to ovalbumin, bencylpenicilloic acid and odinitrocarboxyphenol is described. We used a sandwich type of ELISA by which horse serum was incubated in antigen-coated tubes containing one additional polystyrene ball, followed by rabbit anti horse IgE serum. The tubes were then incubated with biotinylated goat anti rabbit globulin followed by avidin coupled to phosphatase. Endpoint titrations were compared. The ELISA is highly reproducible due to the pretreatment of the polystyrene with glutaraldehyde. The increased antigen surface area led to a higher sensitivity of the test. The assay can be easily modified for the measurement of other Ig classes and of IgE of other antigen specificities.