- Email: [email protected]
Methohexital Sodium, Brevane, Anesthesia for Calves and Sheep1
251
TECHNICAL NOTE REFERENCES
years. Time required for the determination allows hourly sampling from four animals and processing the samples during the intervals.
(1) CONWAYE. J., AN1) BYRNE, A. 1933. MicroDetermination of Amnlonia. Biochem. J., 27 : 426. (2) FENI~ER, 1:~., AND ELLIOT, J. M. 1963. Quantitative Method for Determining the Steam Volatile Fatty Acids in Rumen Fluid by Gas Chromatography. J. Animal Sci., 22" 624.
H. FENNER. Department of Yeterinary and Animal Science University of Massachusetts Amherst
METHOHEXITAL
SODIUM, BREVANE, ANESTHESIA CALVES AND SHEEP 1
Brevane ~ is a short-acting general anesthetic widely used in minor surgery on dogs and cats (1). Results given in this report support its use on calves and sheep. Calves recovered faster from this drug than from other anesthetics TABLE 1 Approximate dosages of methohcxltal sodium for general anesthesia " Species
Initially
--(m~
Maintenance b
of 2.5% solution)
Calf (100 lb) 3-5 to effect, 1-/3 min (250 lb) 5-7 to effect, 4-/4-5 min Sheep ¢ (100 lb) 4-6 to effect, 1-/4 min (200 ]b) 5-8 to effect, 2-/5 min Dosages required were reduced when preanesthetic agents were used. Dosages given are based on day-old solutions. b In long operations the patients gradually required less anesthetic. CA tranquilizer or muscle relaxant may be advisable, depending on the type of surgery, since the sheep often lightened quickly and then struggled some as more anesthetic was given. Scientific article No. A-1163. Contribution No. 3636 of the Maryland Agricultural Experiment Station, University of Maryland, College Park. 2 Corn States Products, Inc., Omaha, Nebraska.
RHYTHMIC
CONTRACTIONS THE
and were usually ambulatory in 30 to 90 min after stopping the infusion; whereas, Nembutaloanesthetized calves were down for from 10 to 18 hr. Brevane also has a wide effective threshold, especially in sheep, which increases its safety. Dosages required are given in Table 1. Use of an endotracheal tube with inflatable cuff has been found to be essential, especially in calves. Three calves were lost before this requirement was appreciated. We now strive for rapid induction and immediate placement of the endotracheal tube. ACKNOkVLEDG]~ENT
Dr. A. C. Brown suggested this drug. Dr. James C. Smith, J. H. Nicolai, H. F. Downey, R. J. McCormick, R. T. Bowman, and F. C. Blank assisted with this work. WOLCOTT E . STEWART
Experimental Surgery Laboratory Dairy Science Department University of Maryland College Park REFERENCE
(1) LVNB, W. V. 1963. Small Animal Anesthesia. p. 182. Lea and Febiger, Philadelphia.
OF THE BOVINE
Contractile tissue in the mammary gland has been studied primarily with respect to milk letdown (1-4). Recent studies at this laboratory on intramammary pressures showed evidence of teat sphincter contractions. Subsequently, teat sphincter contractions were recorded in the bovine during the estrous cycle and within 36 hr following stilbestrol administration (75 nag, ira). These contractions did not occur during the anestrous period. Simultaneous electromyograms were also obtained from the teat sphincter area. A typical recording is shown (Figure 1). The recordings showed the occurrence of a rhythmic contraction of the teat sphincter every
FOR
0
2
4
TEAT
6
8
I0
SPHINCTER
12
IN
1 4 16 "l@ 20 22 24 26 28 30 32 34 36 SECONDS
FIG. 1. Electromyogram and teat sphincter contraction which occurred during the estrus cycle. 15 to 40 see during its active phase. Pressure of contractions varied from 10 to 30 mm ttg. Spontaneous test sphincter contractions oc-
TECHNICAL NOTE REFERENCES
years. Time required for the determination allows hourly sampling from four animals and processing the samples during the intervals.
(1) CONWAYE. J., AN1) BYRNE, A. 1933. MicroDetermination of Amnlonia. Biochem. J., 27 : 426. (2) FENI~ER, 1:~., AND ELLIOT, J. M. 1963. Quantitative Method for Determining the Steam Volatile Fatty Acids in Rumen Fluid by Gas Chromatography. J. Animal Sci., 22" 624.
H. FENNER. Department of Yeterinary and Animal Science University of Massachusetts Amherst
METHOHEXITAL
SODIUM, BREVANE, ANESTHESIA CALVES AND SHEEP 1
Brevane ~ is a short-acting general anesthetic widely used in minor surgery on dogs and cats (1). Results given in this report support its use on calves and sheep. Calves recovered faster from this drug than from other anesthetics TABLE 1 Approximate dosages of methohcxltal sodium for general anesthesia " Species
Initially
--(m~
Maintenance b
of 2.5% solution)
Calf (100 lb) 3-5 to effect, 1-/3 min (250 lb) 5-7 to effect, 4-/4-5 min Sheep ¢ (100 lb) 4-6 to effect, 1-/4 min (200 ]b) 5-8 to effect, 2-/5 min Dosages required were reduced when preanesthetic agents were used. Dosages given are based on day-old solutions. b In long operations the patients gradually required less anesthetic. CA tranquilizer or muscle relaxant may be advisable, depending on the type of surgery, since the sheep often lightened quickly and then struggled some as more anesthetic was given. Scientific article No. A-1163. Contribution No. 3636 of the Maryland Agricultural Experiment Station, University of Maryland, College Park. 2 Corn States Products, Inc., Omaha, Nebraska.
RHYTHMIC
CONTRACTIONS THE
and were usually ambulatory in 30 to 90 min after stopping the infusion; whereas, Nembutaloanesthetized calves were down for from 10 to 18 hr. Brevane also has a wide effective threshold, especially in sheep, which increases its safety. Dosages required are given in Table 1. Use of an endotracheal tube with inflatable cuff has been found to be essential, especially in calves. Three calves were lost before this requirement was appreciated. We now strive for rapid induction and immediate placement of the endotracheal tube. ACKNOkVLEDG]~ENT
Dr. A. C. Brown suggested this drug. Dr. James C. Smith, J. H. Nicolai, H. F. Downey, R. J. McCormick, R. T. Bowman, and F. C. Blank assisted with this work. WOLCOTT E . STEWART
Experimental Surgery Laboratory Dairy Science Department University of Maryland College Park REFERENCE
(1) LVNB, W. V. 1963. Small Animal Anesthesia. p. 182. Lea and Febiger, Philadelphia.
OF THE BOVINE
Contractile tissue in the mammary gland has been studied primarily with respect to milk letdown (1-4). Recent studies at this laboratory on intramammary pressures showed evidence of teat sphincter contractions. Subsequently, teat sphincter contractions were recorded in the bovine during the estrous cycle and within 36 hr following stilbestrol administration (75 nag, ira). These contractions did not occur during the anestrous period. Simultaneous electromyograms were also obtained from the teat sphincter area. A typical recording is shown (Figure 1). The recordings showed the occurrence of a rhythmic contraction of the teat sphincter every
FOR
0
2
4
TEAT
6
8
I0
SPHINCTER
12
IN
1 4 16 "l@ 20 22 24 26 28 30 32 34 36 SECONDS
FIG. 1. Electromyogram and teat sphincter contraction which occurred during the estrus cycle. 15 to 40 see during its active phase. Pressure of contractions varied from 10 to 30 mm ttg. Spontaneous test sphincter contractions oc-