2007 - 76 (4)

To control Mycoplasma hyopneumoniae infections, the use of antibiotics in feed or water is a common practice.Unfortunately, information concerning the susceptibility of M. hyopneumoniae to different antimicrobials isvery scarce. The in vitro susceptibility of 21 M. hyopneumoniae field isolates was determined in this study using abroth microdilution technique. Acquired resistance to spectinomycin, oxytetracycline, doxycycline, gentamicin,florfenicol and tiamulin was not observed. One isolate showed acquired resistance to lincomycin, tilmicosin andtylosin, but was susceptible to all other antibiotics tested. For 5 isolates, the MIC-values of flumequine were >16 μg/ml, while the MIC50-value was 2 μg/ml. The MIC-values of enrofloxacin for these 5 isolates were ≥ 0.5μg/ml, the MIC50 being 0.06 μg/ml. This is the first report showing acquired resistance against macrolides, lincosamidesand fluoroquinolones in M. hyopneumoniae field isolates.

Major losses of body weight and fat reserves during the first lactation are a cause of unsatisfying reproductiveperformances in primiparous sows. This study, conducted in three commercial sow herds, investigatedwhether weaning the sows three days earlier together with administering altrenogest was effectivefor improving reproductive performance (weaning-to-estrus interval, pregnancy rate after firstinsemination, total litter size and number of live born piglets in the second litter) and body condition. Inthe herds suffering from the second litter syndrome, a non-significant improvement of the second litter sizewas found with on average 1.9 extra piglets born. During the treatment period, the treated sows gainedon average 1.4 mm back fat, while the control sows lost 0.4 mm back fat. In conclusion, the treatment isuseful for putting the sows in better condition at the moment of insemination and it may possibly improvereproductive performance in farms with the second litter syndrome.

Paper in Dutch

Paper in Dutch

Numerous complications can be encountered during or after performing dental extractions in man,or in animals regularly seen in veterinary practice, including dogs and cats, lagomorphs, rodents and thehorse. Obvious determinant factors for intraoperative complications related to tooth extraction are surgicalexpertise and the availability of specialized instruments. The most commonly seen problems during anextraction procedure include tooth fracture and damage of surrounding structures such as neighboringteeth, soft tissues and the surrounding bone. Postoperative complications are mainly related to the persistenceor development of infection in and around the vacant alveolus. Rarely encountered post-extractionproblems include jaw fracture, local nerve dysfunction and spread of infection to more distant locationsincluding sinuses and the central nervous system. In the hypsodont dentition of lagomorphs, rodents andhorses, tooth loss may induce the development of wear abnormalities due to the continuous eruption oftheir teeth.

Several techniques have been developed to extract teeth in different animal species regularly seen inveterinary practice. Many of these techniques have a lot of similarities with human extraction techniques,whereas others are species specific. Overall, they can be divided into simple or closed extractions, andsurgical extraction techniques. Simple extractions involve the removal of teeth or root fragments using anintra-oral approach and without exposing or removing alveolar bone. More complex intra- or extra-oralapproaches and surgical techniques are used during surgical extractions. This paper reviews the currentconcepts of the different methods for removing teeth in horses, dogs, cats, lagomorphs and rodents, andcompares them with human exodontic procedures.

The most frequent laboratory abnormalities in patients with congenital portosystemic shunts (CPSS)are microcytosis, hypoglycemia, hypoalbuminemia, hypoproteinemia, increased liver enzyme activities,decreased blood urea nitrogen (BUN) and urate crystalluria. The microcytosis is probably due to impairediron transport. Hypoglycemia, hypoalbuminemia, hypoproteinemia and decreased BUN are partly dueto decreased hepatic synthesis. Prolonged coagulation times are also common. A presumptive diagnosisof CPSS is based on the combination of the history, clinical signs, clinicopathological abnormalities andabnormal liver function tests such as serum bile acid and venous ammonia concentrations. Nowadays,determination of pre- and postprandial serum bile acids is the most commonly performed liver functiontest because of the high sensitivity and greater convenience compared to plasma ammonia concentration.Confirmation of the diagnosis is only possible by visualizing the shunting vessel by medical imaging techniquesor during surgery.

Congenital portosystemic shunts (CPSS) are hepatic vascular anomalies which can affect any breed ofdog or cat. Extrahepatic CPSS are most commonly observed in cats and small dogs, whereas intrahepaticCPSS are more likely to affect large breed dogs. A hereditary basis has been observed in some dog breeds.Affected animals are usually presented at young age with a variety of neurological, gastrointestinal, urinaryor other signs. Signs of hepatic encephalopathy often predominate. The pathogenesis of this condition isnot yet completely understood and is probably multifactorial. The underlying cause is probably the influenceon the brain of one or more toxins which normally speaking should be detoxified by the liver. Ptyalismis a very common sign in cats with CPSS.