Chemical capture of free-ranging cattle: Immobilization with xylazine or medetomidine, and reversal with atipamezole

Abstract

Twenty-nine free-ranging Norwegian cattle were captured with xylazine (n = 20) or medetomidine (n = 9) using a tranquilizing gun, and the time from darting to recumbency (induction time) was recorded. Twenty-eight animals were given atipamezole IV 15-100 min after darting, and the effects of the antagonist were evaluated. Blood samples (n = 19) for haematology and serum chemistry were collected within 10 min after immobilization was induced. Xylazine (0.55 +/- 0.18 mg/kg; mean +/- SD; n = 18) or medetomidine-HCl (0.039 +/- 0.10 mg/kg; n = 8) induced complete immobilization after a single darting with sternal or lateral recumbency, the induction times being 9.6 +/- 3.8 and 12.0 +/- 6.8 min, respectively. No difference in the clinical effects of the two drugs was observed. Rapid reversal was achieved with 0.057 +/- 0.017 and 0.077 +/- 0.019 mg/kg of atipamezole-HCl in xylazine- and medetomidine-treated animals, respectively. All the animals stood within 2 min after IV administration of the antagonist. Seven animals showed signs of excitement shortly after reversal, but these side-effects were of brief duration. Heavy resedation with relapse into recumbency was seen 3-4 h after reversal in two cows captured with xylazine, while moderate resedation was observed in two medetomidine-treated animals 2 h after reversal. Except for the plasma glucose concentration, which was elevated in both xylazine- and medetomidine-treated animals, the mean values of the haematological and plasma chemical parameters were within the reference ranges established for Norwegian cattle.(ABSTRACT TRUNCATED AT 250 WORDS)

A pharmacokinetic study including some relevant clinical effects of medetomidine and atipamezole in lactating dairy cows

“…It is possible that the dose of atipamezole relative to medetomidine (5 : 1) used in this study and in several others is too low for persistent reversal in the bovine. Arnemo & Søli (1993, 1995) used 2 mg atipamezole per mg medetomidine in free‐ranging cattle and reported resedation after 1–2 h or 3–4 h following the injection of atipamezole by the i.v. or intramuscular (i.m.)…”

Food intake and rumen motility in dwarf goats. Effects of atipamezole on the inhibitory effects induced by detomidine, medetomidine and romifidine

“…analgesia and relief of anxiety) are also considered to be beneficial for this purpose (Virtanen, 1986(Virtanen, , 1989Lammintausta, 1991;Ruffolo et al, 1993). An advantage of a2-adrenoceptor agonists in surgery on animals is that their effects can be quickly reversed by parenteral administration of a2-adrenoceptor antagonists (Virtanen et al, 1989;Jones and Young, 1991;Kamerling et al, 1991;Nishimura et al, 1992;Arnemo and S~li, 1993). Other effects induced by az-adrenoceptor agonists include hypothermia (Virtanen, 1989;Van Miert and Van Duin, 1991), hypertension followed by hypotension and bradycardia (Virtanen, 1989;Van Miert and Van Duin, 1991;England et aL, 1992;Ruffolo et aL, 1993).…”

Remote chemical immobilisation method for free‐ranging Australian cattle

“…However, the dosage of xylazine used for darting the cattle was much higher than that traditionally given through hand injection to domestic cattle . Free‐ranging, excited or aggressive cattle have an increased resistance to the effects of xylazine; hence doses of up to 1.6 mg/kg of xylazine have previously been used for the capture and immobilisation of such individuals . However, high doses of xylazine in cattle are associated with high mortality rates and should be used with extreme caution .…”

“…Cattle ( Bos taurus and B. indicus ) are often encountered under free‐ranging conditions in Australia, particularly with extensive pastoral livestock and ‘feral’ cattle in the rangelands of Australia. Free‐ranging domestic cattle are also sporadically encountered in cases of escapees from loading yards or saleyards, transport vehicle rollovers or on landholdings lacking appropriate yard facilities . Capture of cattle in situ (i.e.…”