Aeromonas hydrophila conjunctivitis in a pet parrot (Amazona versicolor).

A bilateral conjunctivitis in a pet parrot (Amazona versicolor) is reported. Aeromonas hydrophila was isolated in pure culture from both eyes and considered of diagnostic significance. Biochemical characteristics and antimicrobial susceptibility of the strain were studied, as were the factors that could have contributed to the clinical conjunctivitis and the role of A. hydrophila as an opportunistic pathogen.     

Validation of diagnostic tests for determination of magnesium status in horses with reduced magnesium intake

OBJECTIVE: To evaluate the diagnostic value of serum concentrations of total magnesium (tMg) and ionized magnesium (iMg), concentrations of magnesium (Mg) in muscle, intracellular Mg (icMg) concentrations, urinary Mg excretion (EMg), Mg clearance (CMg), and fractional clearance of Mg (FCMg) in horses fed diets with Mg content above and below National Research Council recommendations. ANIMALS: 9 young female horses. PROCEDURES: 6 horses were fed a reduced-Mg diet for 29 days followed by an Mg-supplemented diet for 24 days. Control horses (n = 3) were fed grass hay exclusively. Blood, urine, and tissue samples were collected, and an Mg retention test was performed before and after restriction and supplementation of Mg intake. Serum tMg, serum iMg, muscle Mg, icMg, and urine Mg concentrations were measured, and 24-hour EMg, CMg, and FCMg were calculated. RESULTS: Reductions in urinary 24-hour EMg, CMg, and FCMg were evident after 13 days of feeding a reduced-Mg diet. Serum tMg and iMg concentrations, muscle Mg content, and results of the Mg retention test were not affected by feeding the Mg-deficient diet. Spot urine sample FCMg accurately reflected FCMg calculated from 6- and 24-hour pooled urine samples. Mean +/- SD FCtMg of horses eating grass hay was 29 +/- 8%, whereas mean FCtMg for horses fed a reduced-Mg diet for 29 days was 6 +/- 3%. CONCLUSIONS AND CLINICAL RELEVANCE: The 24-hour EMg was the most sensitive indicator of reduced Mg intake in horses. Spot sample FCMg can be conveniently used to identify horses consuming a diet deficient in Mg.     

Effect of oxytocin treatment in sows on umbilical cord morphology,meconium staining,and neonatal mortality of piglets

OBJECTIVE: To evaluate the effect of 2 oxytocin products administered to sows at the onset of fetal expulsion on the integrity of umbilical cords, meconium staining, and piglet mortality. ANIMALS: 2099 neonatal pigs. PROCEDURE: 180 parturient sows were randomly assigned to 3 stratified groups of 60 sows each. Two groups of sows were injected IM at the onset of fetal expulsion with 1 of 2 oxytocin commercial products (20, 40, or 50 U for sows weighing 120 to 150 kg, 151 to 250 kg, or > or = 251 kg, respectively). Control sows were treated IM with saline (0.9% NaCI) solution. Farrowing time, expulsion intervals, and numbers of stillborn and liveborn piglets were recorded for each sow. Piglets were evaluated for inspiratory effort, heart rates, and degree of meconium staining of skin (nonstained, and moderately or severely stained). Umbilical cords were classified as normal in appearance, edematous, congested, hemorrhagic, or ruptured. RESULTS: Oxytocin-treated sows had a significant decrease in farrowing time and expulsion intervals and also had a significantly higher number of stillborn piglets per litter, compared with control sows. The number of piglets per litter with ruptured and hemorrhagic umbilical cords was significantly greater in oxytocin-treated sows, compared with control sows. In near-death stillborn piglets, oxytocin treatment significantly decreased inspiratory efforts at birth and increased the rate and severity of meconium staining, compared with saline treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Oxytocin given to sows at the onset of fetal expulsion significantly increases the rate of fetal distress, anoxia, and intrapartum death in piglets.     

Pharmacokinetics of marbofloxacin in mature horses after single intravenous and intramuscular administration

The pharmacokinetic behaviour of marbofloxacin, a new fluoroquinolone antimicrobial agent developed exclusively for veterinary use, was studied in mature horses (n = 5) after single-dose i.v. and i.m. administrations of 2 mg/kg bwt. Drug concentrations in plasma were determined by high performance liquid chromatography (HPLC) and data obtained were subjected to compartmental and noncompartmental kinetic analysis. This compound presents a relatively high volume of distribution (V(SS) = 1.17 +/- 0.18 l/kg), which suggests good tissue penetration, and a total body clearance (Cl) of 0.19 +/- 0.042 l/kgh, which is related to a long elimination half-life (t(1/2beta) = 4.74 +/- 0.8 h and 5.47 +/- 1.33 h i.v. and i.m. respectively). Marbofloxacin was rapidly absorbed after i.m. administration (MAT = 33.8 +/- 14.2 min) and presented high bioavailability (F = 87.9 +/- 6.0%). Pharmacokinetic parameters are not significantly different between both routes of administration (P>0.05). After marbofloxacin i.m. administration, no adverse reactions at the site of injection were observed. Serum CK activity levels 12 h after administration increased over 8-fold (range 3-15) compared with pre-injection levels, but this activity decreased to 3-fold during the 24 h follow-up period. Based on the value of surrogate markers to predict clinical success, Cmax/MIC ratio or AUC/MIC ratio, single daily marbofloxacin dose of 2 mg/kg bwt may not be effective in treating infections in horses caused by pathogens with an MIC > or = 0.25 microg/ml. However, if we use a classical antimicrobial efficacy criteria, marbofloxacin can reach a high plasma peak concentration and maintain concentrations higher than MICs determined for marbofloxacin against most gram-negative veterinary pathogens throughout the administration period. Taking into account the fact that fluoroquinolones are considered to have a concentration-dependent effect and a long postantibiotic effect against gram-negative bacteria, a dose of 2 mg/kg bwt every 24 h could be adequate for marbofloxacin in horses.     

Intraspinal synovial cyst in a dog

An eight-year-old, male Siberian husky cross was referred with a history of an acute onset of pelvic-limb ataxia and paraparesis. Radiography and subsequent myelography of the spine revealed an extradural compression of the spinal cord at the level of the 13th thoracic (T13) to first lumbar (L1) vertebrae. Hemilaminectomy resulted in the successful removal of an extradural cystic lesion. The morphological diagnosis based on histopathology was a synovial cyst with chondromatosis. There were no postoperative complications, and the dog's condition improved markedly. At two years postoperatively, the animal remains normal on both physical and neurological examination. To the authors' knowledge, this article is the first report of an intraspinal synovial cyst in a dog.     

Morphological changes in the lungs of meconium-stained piglets.

Meconium staining of the skin is a common event associated with fetal hypoxia, stillbirths, weak-born piglets, and neonatal mortality. Aspiration of meconium leads to meconium aspiration syndrome (MAS). This study was undertaken to assess the relationship between the degree of meconium staining of the skin at birth, meconium aspiration, and pulmonary changes in porcine neonates. A total of 353 farrowing sows and 3,693 born piglets were monitored during parturition and for 15 days after delivery. Umbilical cords were classified as normal or ruptured. Meconium staining in the skin was graded as nonstained, mildly, moderately, and severely stained. Mortality from birth to 15 days of age was 8.4%. The lungs from 60 meconium-stained piglets and 60 lungs from nonstained piglets were collected and microscopically examined for meconium aspiration and inflammation. Rupture of the umbilical cord was significantly higher (P < 0.01) in meconium-stained piglets. Microscopically, 32% and 40% of the lungs had evidence of meconium for the stained and nonstained groups, respectively. The microscopic grade of meconium aspiration and inflammatory cells was not different between nonstained and meconium-stained piglets. Aspiration of meconium induced a granulomatous response in the lungs. It was concluded that the grade of meconium staining is a good indicator of fetal hypoxia, but not a good predictor for meconium aspiration and MAS in piglets.     

Pharmacokinetics and pharmacodynamics of carfentanil and naltrexone in female common eland (Taurotragus oryx).

The pharmacokinetic parameters of carfentanil and naltrexone were determined in the common eland (Taurotragus oryx). Six adult females were immobilized with xylazine (0.23 +/- 0.03 mg/kg i.m.) and carfentanil (0.0169 +/- 0.0005 mg/kg i.m.) for a 45-min period, during which time routine health care procedures were performed. Heart and respiration rates and body temperatures were monitored throughout the immobilization period. A single intramuscular injection of naltrexone (1.66 +/- 0.08 mg/kg i.m.) was sufficient for reversal. The eland were intermittently restrained in a hydraulic squeeze chute for serial blood sample collection via jugular venipuncture during immobilization and up to 48 hr post-immobilization. The quantification of carfentanil and naltrexone in the plasma was performed by liquid chromatography and mass spectroscopy methods. Carfentanil was rapidly absorbed following administration, with the peak plasma concentration (C(max)) at 13.8 min. Naltrexone was readily absorbed and reached C(max) at 23.4 +/- 16.8 min after administration. All animals stood 2.7 +/- 2.2 min after naltrexone administration. Carfentanil has a half-life of 7.7 hr, whereas naltrexone has a much shorter half-life of 3.7 hr. Although respiratory rates appeared to fluctuate widely among animals, heart rates and body temperature remained stable throughout the immobilization. Renarcotization was not noted as a major complication.     

Nicotine decreases food intake through activation of POMC neurons

Smoking decreases appetite, and smokers often report that they smoke to control their weight. Understanding the neurobiological mechanisms underlying the anorexic effects of smoking would facilitate the development of novel treatments to help with smoking cessation and to prevent or treat obesity. By using a combination of pharmacological, molecular genetic, electrophysiological, and feeding studies, we found that activation of hypothalamic α3β4 nicotinic acetylcholine receptors leads to activation of pro-opiomelanocortin (POMC) neurons. POMC neurons and subsequent activation of melanocortin 4 receptors were critical for nicotinic-induced decreases in food intake in mice. This study demonstrates that nicotine decreases food intake and body weight by influencing the hypothalamic melanocortin system and identifies critical molecular and synaptic mechanisms involved in nicotine-induced decreases in appetite.