2002 - 71 (3)

A severe outbreak of lameness with joint and bone lesions and evidence of bacterial infection due to Enterococcus cecorum was diagnosed on a Dutch broiler farm. Morbidity and mortality were as high as 10%, while the remaining chickens performed well. Bacterial chondronecrosis and osteomyelitis with loosening of the femoral heads (femoral head necrosis) in the end stage was the most frequently observed lesion. The same pathological process was seen, though rarely, in the T3/T4 spine articulation. Septicemia resulting in pericarditis, local myositis and, most prominently, bone and joint lesions, was the major diagnosis. E. cecorum could be isolated from nearly all lesions when appropriate isolation methods (blood agar incubated in a carbon dioxide-enriched atmosphere) were used.

A large intra-abdominal mass with several cavities was detected by ultrasound in a nine-year-old apathetic female German Shepherd with a very tense belly. At surgery, a fluctuating mass was found in the middle of the left uterine horn. Neoplasia was suspected and the mass was surgically removed. Histologically, a diagnosis of organizing hematoma was made.

In this case report an anatomical, histologic, hormonal and cytogenetic study of an intersexual sheep was carried out. At the age of 15 months, no udder could be detected in the animal, which had been classified as a female of a heterosexual twin at birth. At the age of 22 months the sheep was diagnosed as an intersex due to the presence of both male and female characteristics, viz. two testicles and a vulva. The hCG stimulation test proved that active Leydig cells were present in the male gonads. Histologic analysis after necropsy showed inflammation and atrophy of the testicular parenchyma. However, at the cytogenetic level, sexual chromosome mosaicism 54, XX / 54, XY was found after lymphocyte culture. These analyses made it clear that the intersex described here was a male pseudohermaphrodite. This condition occurs in less than 0.03% of the total sheep population. The hCG stimulation test can be used to distinguish “pseudo-male” from “pseudo-female” freemartins at a young age and without the need for necropsy.

The first part of the article provided a review of injection anesthesia in reptiles. In the second part, inhalation anesthesia in these species is highlighted. Specific attention is given to the anatomy and physiology of the respiration system in reptiles and the pre-anesthetic preparation. Practical details of the equipment, endotracheal intubation and monitoring are provided. Problems such as breath-holding can occur in reptiles. Another problem is the enormous variability in species and size. In snakes it is common practice to intubate the animal awake and “gas” it down. This technique is neither justified nor possible in venomous snakes. Induction of anesthesia in these animals can be done using different injection techniques (see Part 1) or the box induction. Intubation can be done once the animal is asleep. Lizards have an easily accessible tail vein, while the jugular vein can be used for injection in cooperative chelonians. Propofol is the product of choice for anesthetic induction in these species (see Part 1). However, as in non-venomous snakes, “conscious” intubation is becoming more and more popular in lizards and chelonians. Isoflurane is the most widely used volatile anesthetic in reptiles, although satisfactory results have been reported using sevoflurane in exotic practices in the UK and USA over the last two years.

The first part of the article gives a review of injection anesthesia in reptiles. The specific anatomy and physiology of reptiles are briefly described, along with their pre-anesthetic evaluation. Drugs used for pre-medication, muscle relaxation, local anesthesia and the induction of general anesthesia are discussed. The last section deals with analgesia in reptiles. Chelonians are relatively difficult to anesthetize so injection anesthesia is of great value in this species. Midazolam/ketamine ore an ά2-agonist (medetomidine, xylazine) / ketamine combination can be used successfully. Propofol IV or IO is the agent of choice for induction and minor surgeries not exceeding 20 minutes. In large tortoises (eg. Aldabrachelys gigantean) a muscle relaxant may be indicated to facilitate handling of the head and intubation. Ketamine and zolazepam/tiletamine (zoletil, tilazol) IM are indicated as premedication in snakes. Propofol IV and even methoxital IM or SC can be used for induction and small interventions. In lizards, easy access to the tail and abdominal veins assure intravenous access. For this reason, propofol is used for induction and smaller surgical interventions. Ketamine and alphaloxone/alphadolone IM are good alternatives. Since problems often occur with gas induction, injection anesthesia is usually obligatory in these species before inhalation anesthesia can be performed.