Hyperglycemia, hypernatremia, and hyperosmolarity in 6 neonatal llamas and alpacas

Neonatal camelids can develop hyperglycemia, hypernatremia, and hyperosmolarity in response to a combination of stress and inadequate water intake. Clinical signs of this syndrome include a fine head tremor, ataxia, and a base-wide stance of the hind limbs, but biochemical analyses are necessary to confirm the diagnosis. Camelids appear to be susceptible to this syndrome because of a poor insulin response to hyperglycemia; hypernatremia results from free water loss associated with glucose diuresis. Water loss associated with glucose diuresis may necessitate a higher rate of fluid administration in camelids with this syndrome than is typically used for treatment of hypernatremia in calves.     

Factors affecting the natural transmission of bovine leukaemia virus infection in Queensland dairy herds

Natural transmission of bovine leukaemia virus (BLV) infection in south-eastern Queensland dairy herds was slow in 2 herds with a low to moderate (13 to 22%) prevalence of infection. Infection spread much more rapidly in a herd that had a higher prevalence (42%) when first tested. In a 13 month study of this herd, the cumulative incidence of infection was 24%. In one herd new infections were confined almost entirely to calves of uninfected dams. Following the end of feeding bulk milk to calves, a common practice in dairy herds, no more calves in this herd became infected. In laboratory experiments, neither prolonged housing of susceptible calves with infected cattle, consumption of drinking water contaminated with infected blood, nor inoculation of sheep with saliva from infected cattle resulted in transmission of BLV infection. Sheep were infected by subcutaneous inoculation of a suspension of purified lymphocytes from an infected heifer. The minimum infective dose was 10(3) lymphocytes, equivalent to the number of lymphocytes in approximately 0.1 microliter blood. Thus, procedures involving the transfer of a very small volume of blood from animal-to-animal have the potential to transmit infection.     

Fatal gastrointestinal parasitism in goats: 31 cases (2001-2006)

OBJECTIVE: To evaluate signalment, history, clinical and pathologic findings, and seasonal weather patterns in association with fatal gastrointestinal parasitism in goats. DESIGN: Retrospective case series. ANIMALS: 152 goats that were > 1 day of age. PROCEDURES: Characteristics including age and counts of coccidia oocysts and trichostrongyle ova (eggs) per gram of feces (EPG) in goats that died because of gastrointestinal parasitism and goats that died because of other causes were compared. Weather data and annual incidence of caprine fatal gastrointestinal parasitism were investigated. RESULTS: Death was attributed to gastrointestinal parasitism in 31 of 152 (20%) goats (median age, 5 months; range, 1 month to 7 years); deaths were attributed to coccidiosis (n = 7 goats; median age, 4 months; median EPG, 2,225), trichostrongylosis (6 goats; median age, 1.25 years; median EPG, 3,700), or dual infection (18 goats; median age, 6.7 months; median EPG, 8,088 coccidia and 5,475 trichostrongyles). Sudden onset of weakness or death was a common historical finding; diarrhea was evident in 15 goats. Common postmortem findings in these goats included cachexia, tissue pallor, poorly formed feces, and mesenteric lymphadenomegaly. Wet weather in spring and summer was associated with increased annual incidence of fatal gastrointestinal parasitism in goats. CONCLUSIONS AND CLINICAL RELEVANCE: Gastrointestinal parasitism is an important cause of death in goats. Clinical signs may not develop until just prior to death, and diagnosis is achieved via parasitologic evaluation of feces and necropsy. Seasonal weather patterns should be considered on an annual basis when designing parasite control programs for goats.     

Gas-phase ionic reactions: dynamics and mechanism of nucleophilic displacements

Nucleophilic displacement reactions (the SN2 reaction) of ions in the gas phase are a prototypical reaction system that allows a study of dynamics, mechanisms, and structure-energy relations. This article reviews aspects of the kinetics (especially the applicability of statistical reaction rate theory), the relation of structure and reactivity, and the effects of small numbers of solvent molecules on the reaction and compares the behavior of the ionic reaction in the gas phase with that in solution.     

Minimum alveolar concentration of desflurane in llamas and alpacas

OBJECTIVE: To determine the minimum alveolar concentration (MAC) of desflurane in llamas and alpacas. DESIGN: Prospective study. Animals Six healthy adult llamas and six healthy adult alpacas. PROCEDURE: Anesthesia was induced with desflurane delivered with oxygen through a mask. An endotracheal tube was inserted, and a port for continuous measurement of end-tidal and inspired desflurane concentrations was placed between the endotracheal tube and the breathing circuit. After equilibration at an end-tidal-to-inspired desflurane concentration ratio >0.90 for 15 minutes, a 50-Hz, 80-mA electrical stimulus was applied to the antebrachium until a response was obtained (i.e. gross purposeful movement) or for up to 1 minute. The vaporizer setting was increased or decreased to effect a 10-20% change in end-tidal desflurane concentration, and equilibration and stimulus were repeated. The MAC was defined as the average of the lowest end-tidal desflurane concentration that prevented a positive response and the highest concentration that allowed a positive response. RESULTS: Mean +/- SD MAC of desflurane was 7.99 +/- 0.58% in llamas and 7.83 +/- 0.51% in alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: The MAC of desflurane in llamas and alpacas was in the range of that reported for other species.     

Clinical, ultrasonographic, and laboratory findings in 12 llamas and 12 alpacas with malignant round cell tumors

Clinical signs, duration of illness, clinicopathologic findings, and ultrasonographic findings were evaluated in 12 llamas and 12 alpacas with malignant round cell tumors (MRCT). All but 1 animal died or was euthanized. Common clinical findings were anorexia, recumbency or weakness, and weight loss or poor growth. Peripheral lymphadenomegaly occurred in only 7 animals and was detected more often at necropsy than during physical examination. Common clinicopathologic abnormalities were hypoalbuminemia, acidosis, azotemia, anemia, hyperglycemia, and neutrophilia. Ultrasonography detected tumors in 4/6 animals. Cytologic evaluation of fluid or tissue aspirates or histopathology of biopsy tissue was diagnostic in 5/6 cases. A clinical course of 2 wk or less prior to death or euthanasia was more common in animals ≤ 2 y of age (9/11) than in older animals (6/13). Regular examination of camelids to include clinical pathology and evaluation of peripheral lymph nodes may result in early detection of MCRT.