Tierärztliche Hochschule Hannover Vergleichende Studie zur

Publikation 2
Introduction
Abdominal surgery in calves is commonly performed under inhalation anaesthesia
(halothane (Steffey & Howland 1979; Trent & Smith 1984; Staller et al. 1995) or
isoflurane (Kerr et al. 2007)) or using intravenous (IV) or intramuscular (IM) injection
of xylazine and ketamine (Waterman 1981; Rings & Muir 1982; Greene & Thurmon
1988). Even though the benefits of inhalative agents are unambiguous, the
requirement of special equipment renders them unsuitable for field-use. Injection
anaesthesia is most frequently employed in farm animal practice, but is associated
with considerable cardiopulmonary side effects (Campbell et al. 1979; Picavet et al.
2004) while not even providing adequate analgesia for umbilical surgery in all cases
(Rings & Muir 1982).
As an alternative to general anaesthesia, high volume caudal epidural anaesthesia
using a combination of spinal local anaesthetics and α 2 -adrenergic agonists has been
utilised in cattle practice in recent years. Epidural application of 0.1 mg kg -1 xylazine
diluted to a final volume of 0.5 - 0.6 ml kg -1 with procaine (2%) proved to be effective,
safe and economic for umbilical surgery in calves (Meyer et al. 2007), while the
delayed manner of systemic resorption of epidural xylazine induced only mild
cardiopulmonary depressant effects in ruminants (Mpanduji et al. 1999; Meyer et al.
2009). While numerous experimental studies have examined the anaesthetic and
antinociceptive effects of different drug combinations in cattle, few have investigated
reactions to actual surgical trauma. Electrical stimulation or pinprick (Skarda et al.
1990; Prado et al. 1999; Junhold & Schneider 2002) are regarded as good
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