SNAKE BITE IN DOGS F.W.G.
H11.i
Department o f Veterinary Clinical Sciences, Veterinary Clinical Centre, Werribee, Victoria 3030 was d i a g n o s e d in 80 d o g s . Sporting b r e e d s figured prominently. T h e a v e r a g e age was 3.6 y e a r s . T h e c o m m o n e s t p r e s e n t i n g s i g n s w e r e salivation, vomiting, dilated pupils, a b s e n c e of t h e pupillary light reflex, d e p r e s s i o n a n d g e n e r a l i s e d m u s c l e w e a k n e s s , hindlimb ataxia a n d respiratory d i s t r e s s . Sixty-seven cases (84%)o c c u r r e d in 6 w a r m e r m o n t h s of t h e y e a r . Fifty-one dogs (64%) w e r e seen e i t h e r t o b e bitten or in c o n t a c t with a snake. Tiger a n d Brown s n a k e s w e r e implicated o n 32 a n d 3 o c c a s i o n s respectively. An overall recovery r a t e of 87% w a s o b t a i n e d for p a t i e n t s receiving a n t i v e n e n e , fluid a n d s u p p o r t t h e r a p y . T h e period from treatment-to-full recovery w a s s h o r t e r for cases in which t h e bite-to-treatment period w a s o n e h o u r o r less (24h o u r s ) w h e n c o m p a r e d with t h e recovery t i m e for all cases (36 h o u r s ) . T h e p r o g n o s i s w a s p o o r for d o g s p r e s e n t i n g with the triad of c o m p l e t e flaccid paralysis, d y s p n o e a a n d a sub-normal t e m p e r a t u r e . SUMMARY: In 7 y e a r s s n a k e bite
Introduction
Results
Of the domestic animals, i t would appear to be in the dog that snake bite presents the biggest problem (Clarke and Clarke 1975). Whilst there are individual case reports (Fethers 1943; Dickinson 1953; Keep 1957; Gordon 1958) and reviews (Trinca 1959; Lewis 1978) of snake bite in dogs in Australia, a large series of such cases has not been reported previously. This paper records the clinical signs, management and outcome of 80 cases of snake bite in the dog.
The 80 cases made up 0.3% of the total dogs brought to the hospital for treatment, excluding speys, castrations and vaccinations. Fifty-one dogs (64%) were reported to have been seen in contact with a snake. Many owners witnessed their dog either finding a snake and being bitten or fighting a snake. Sometimes the dog had been found with a dead snake. Thirty-two Tiger snakes and 3 Brown snakes were positively identified. Identification of the species in the remainder was
Materials and methods Snake bite \\as diagnowd in 80 dogs admitted to the Melbourne Uiiiveinitp Hospital during the last 7 years. The breed di\tribution varied but >porting dogs figured prominently. 17 golden laboradors and their crosses, 7 cocker spanieh, and 7 pointers. There were ;dl males, 26 females and 10 speyed females. Their ages ranged from 2 months to 13 years with 27 cases two yearr old or younger. The average age was 3.6 years. The procedure adopted f o r the management, diagnosis and treatnieni \\a!, \imilar 10 that iised for snahe bite in cats and the details have becn published previously (Hill and Campbell 1Y78). A firm diagnosis of snake bite was made in each case from the presenting neurological features and one or more of [ l i e following: positive evidence of contact with a snake; prevailing hot lreathcr conditions favouring snake activity; the finding of snake bite-like puncture \\ounds in the skin of the patient; elevated p l a m a creatiniiie phosphokinase (CPK) levels. When the bite was not witnessed, a favourable responbe and recovery by the patient after receiving 3000 units of Tiger rnahe antiveiiene or both Tiger snake and 500 units of Brown snake antiveiiene wits raken to he confirmation of (he diagnobis. Atropine hulphate %as an additional and frequent trt'atmenl for t h c alfected d Three dogs sustained a second w a k e bite 7 , I I and 18 nioi after receiving their fir5r. Tw o dog\ \ecn cairyiiig dcad mi did not develop envenoniation and are ecludtrd f r o m the series.
'I'ABLE 1
82
Frequency of Clinical Signs in 80 Dogs with Snake Bite Sign Dilated pupils Anisocoria Pupil light reflex absent Pupil light reflex sluggish Depression with generalised muscle weakness Vomiting (reported or observed) Salivation Hindlimb ataxia Respiratory signs (panting, tachypnoea, dyspnoea) Total flaccid paralysis Isolated muscle tremors Quadriplegia Diarrhoea Pharyngeal, tongue or vocal chord paralysis Elevated rectal temperature Depressed rectal temperature Cyanosed mucous membranes
Times Recorded
61 1 50 15 48 45 40 31 31 20
19 8 4 4 21
13 8
.4usrra/ian Vereririar~.lourri;l/, V o l . 5 5 , Februar?, 1979
not possible. For dogs seen to be bitten, the time from bite to presentation at the hospital was a mean of 3.1 hours. The time lapse for all cases, from either the onset of illness in cases not seen to be bitten or :he actual snake bite, to admission into the hospital was a mean of 5.8 hours. The signs are given in Table 1 which shows that dilated pupils, absence or reduction of :he pupillary light reflex (PLR), depression with generalised muscle weakness, vomiting, salivation, respiratory signs and hindlimb ataxia were the most commonly observed. Table 2 records the frequency of clinical signs in 27 dogs seen to have been bitten and presented for treatment within one hour of the event. In this group the predominant clinical signs were similar, however in 6 cases the pupils were normal and in 8 a PLR was present. Snake bite puncture wounds were found in the skin of 8 dogs. There was little or no reaction at the site of the bites. On 3 occasions owners reported that their dog had collapsed dramatically and momentarily within seconds of receiving the snake bite and then recovered only subsequently to develop the typical signs of envenomation. Haematuria or haemoglobinuria/ myoglobinuria was observed in 19 cases. Plasma CPK values were estimated in 16 cases and were always elevated with a mean of 1271 mu/ml (range 137 to 5016 mu/ml). Appropriate antivenene was used, when the species of snake involved had been identified. Otherwise Tiger snake antivenene was given alone, or combined with Brown snake antivenene. Seventy-five cases received anti-venene therapy. Seventy were given 3000 units Tiger snake antivenene, 3 received 500 units Brown snake antivenene and 2 received both 3000 units and 500 units of Tiger and Brown snake antivenene respectively. One dog, known to have been bitten by a TABLE 2
Frequency of Clinical Signs in 27 Dogs Presented for Treatment within 1 Hour of Having Been Seen to be Either in contact with or Bitten by a Snake. Signs Frequency Salivation 21 18 Vomiting (seen or reported by owner) Depression 12 Hindlimb ataxia 16 8 Isolated muscle tremors Quadriplegia 2 Dilated pupils 20 1 Anisocoria Normal pupils 6 8 Pupil light reflex present Pupil light reflex absent 9 Pupil light reflex sluggish 10 Respiratory signs (panting, tachypnoea) 14 Atisfralian Vererinary .lourrial, Vol. 5 5 , February, 1979
Tiger snake 16 hours before treatment, received a n additional 1500 units of Tiger snake antivenene, when there was no clinical improvement 12 hours following the initial dose. Lactated Ringers fluid was given intravenously by drip routinely and maintained until a definite clinical improvement was observed. Atropine sulphate was frequently administered to control salivation. Further infrequent therapy was oxygen, antibiotic cover, corticosteroids and antihistamines. One dog found carrying a dead Tiger snake in its mouth, but not showing signs of envenomation, at the owner's insistence was given 3000 units Tiger snake antivenene a n d immediately developed a n anaphylactic reaction, which was successfully treated with adrenalin and corticosteroid therapy. Of the 75 cases receiving antivenene, 65 survived and recovered completely (87%). The recovery rate was 85% for the 47 cases either having known contact with or seen to be bitten by a snake and receiving antivenene. Recovery time varied from 8 hours to 6 days (mean of 36 hours). The mean recovery time for the dogs receiving antivenene within one hour of being bitten was 24 hours. Five dogs died before antivenene could be given to them. Complete flaccid paralysis, cyanosis, dyspnoea a n d h y p o t h e r m i a with rectal temperatures below 35" were consistent findings in these cases. Two had been bitten 24 hours previously and another 6 hours prior to presentation. The remaining t w o were brought to the clinic within one hour of the snake bite. Ten dogs died following antivenene therapy. Again these cases invariably presented in terminal collapse, cyanosed, dyspnoeic and hypothermic. Many of them had been either bitten or ill for a t least 12 hours but two cases were seen within a n hour of being bitten, and failed to respond to antivenene and supportive therapy. Three dogs bitten by Brown snakes and receiving Brown snake antivenene recovered. The two dogs given Tiger and Brown snake antivenene had been ill for over 12 hours before presentation. The bites were not witnessed. Both cases showed complete flaccid paralysis, dyspnoea and were hypothermic. One died, the other made a slow recovery over 4 days. Autopsies were performed on 8 cases. Puncture wounds were found in the skin of the head and forelimbs of 6 of the dogs. The wounds were accompanied by subcutaneous haemorrhage and slight oedema. There were no consistent gross findings. Occasionally congestion of the lungs and kidneys and haemoglobin/myoglobinuria were reported. Histologically, generalised acute and hyaline degeneration of skeletal and myocardial muscles were consistent findings. 83
30
2:
21
al
m ES al
: n 11
r jun
lul
aug
sep
oct
nov
Figure 1 Monthly ncidence of cases
Of
dec
Ian
'eb
mar apr
may
snakc bite In dogs
Sixty-seven cases (84To) occurred in the warmer months of the year between October a n d March (Figure 1 ) . Thirty-$even cases (46%) were in the months of December a n d January. Discussion
The location and environs of the University Veterinary Clinical Hospital a n d the p r e p o n d e r a n c e of T i g e r s n a k e s in t h e neighbourhood have been discussed previously (Hill and Campbell 1978). In this series of bites, 32 Tiger snakes were identified, making it possible to confirm the importance of this species of snake in the Werribee area. The majority of cases occurred in the summer months which is consistent with previous findings (Hill and Campbell 1978; Lewis 1978). A few dogs were bitten in the cooler months of the year, when warm changes in the prevailing weather encouraged snakes out of hibernation prematurely. Many more dogs were seen t o be either bitten by o r in contact with a snake (64%) compared to the cases of cat snake bite (16%). Consequently the illness o r bite-to-treatment time for dogs was much shorter (mean 5.8 hours) than for the cats (mean 21 hours). I n spite of this, the recovery rates for dogs a n d cats receiving antivenene were similar (dogs 87"10, cats 89%), a n d would appear to substantiate earlier findings that cats are very resistant to snake envenomation (Trinca 1959). Earty signs frequently reported were salivation and vomiting. Salivation was not recorded in the three cases of Brown snake bite, but with one of them vomiting occurred. Dilated pupils, unresponsive to light, were not present in all early cases of envenomation, a n d there is a danger of 84
misdiagnosis in such cases, more particularly where the snake bite is not witnessed. Consistently plasma CPK was highly elevated a n d proved to be a useful confirmatory laboratory aid in these cases. The composition of the Tiger snake venom has been discussed in a previous paper (Hill and Campbell 1978). Neurotoxin, myotoxin, a defibrinating factor a n d haemolysin components are probably responsible for the degeneration of skeletal muscle fibres, r-lease of CPK into the c i r c u I a t i o n , h a e m a t u r i a a n d h a e m og 1obi nuria/myoglobinuria. It must be emphasised that in Victoria in cases of animal snake bite where the identity of the snake is uncertain, both Tiger and Brown snake antivenene should be used for treatment. I t is only the preponderance of Tiger snakes i n the immediate environs of the University Veterinary Hospital which allows the use of Tiger snake antivenene alone for cases either not seen t~ be bitten o r where the species of snake is not identified. T h e recovery rate was good in patients receiving antivenene therapy. Signs necessitating a poor prognosis were complete flaccid paralysis, dyspnoea a n d a sub-normal temperature. Generally these dogs had been ill f o r over 12 hours. However on occasions cases were presented with this triad of signs within an hour of being bitten and one can only assume that they received a very efficient bite a n d a large volume of venom. For snake bite in cats, n o correlation was possible between the bite-to-treatment period a n d the treatment t o full recovery period (Hill a n d Campbell 1978). In this series of dogs it was possible to demonstrate that recovery was quicker when treatment was administered within one hour of the bite. Antivenene is prepared by hyperimmuniying horses with appropriate snake venom. An anaphylactic reaction occurred in one dog inimediately following the administration of the heterologous serum, indicating that it is advisable to administer either adrenalin o r a n antihistamine prior to giving antivenene. At least i t is essential that these drugs a r e to hand u h e n antivenene is given. T h e three dogs in this series receiving a second snake bite months after receiving their first were given adrenalin before the administration of repeat antivenene therapy.
I
Acknowledgments erateful to former and present interns in the I k p a r t of Veterinary Clinical Sciences for supplying nian) of the
an1
iiiciit
case details, to Dr J. S. M'ilhinson and hi, .;taff lor u r i n a l y w 5 and tlic C P h estimations a n d to meinber\ of the Department 0 1 Paraclinical Science\ for the autop5) report
H11.i
Department o f Veterinary Clinical Sciences, Veterinary Clinical Centre, Werribee, Victoria 3030 was d i a g n o s e d in 80 d o g s . Sporting b r e e d s figured prominently. T h e a v e r a g e age was 3.6 y e a r s . T h e c o m m o n e s t p r e s e n t i n g s i g n s w e r e salivation, vomiting, dilated pupils, a b s e n c e of t h e pupillary light reflex, d e p r e s s i o n a n d g e n e r a l i s e d m u s c l e w e a k n e s s , hindlimb ataxia a n d respiratory d i s t r e s s . Sixty-seven cases (84%)o c c u r r e d in 6 w a r m e r m o n t h s of t h e y e a r . Fifty-one dogs (64%) w e r e seen e i t h e r t o b e bitten or in c o n t a c t with a snake. Tiger a n d Brown s n a k e s w e r e implicated o n 32 a n d 3 o c c a s i o n s respectively. An overall recovery r a t e of 87% w a s o b t a i n e d for p a t i e n t s receiving a n t i v e n e n e , fluid a n d s u p p o r t t h e r a p y . T h e period from treatment-to-full recovery w a s s h o r t e r for cases in which t h e bite-to-treatment period w a s o n e h o u r o r less (24h o u r s ) w h e n c o m p a r e d with t h e recovery t i m e for all cases (36 h o u r s ) . T h e p r o g n o s i s w a s p o o r for d o g s p r e s e n t i n g with the triad of c o m p l e t e flaccid paralysis, d y s p n o e a a n d a sub-normal t e m p e r a t u r e . SUMMARY: In 7 y e a r s s n a k e bite
Introduction
Results
Of the domestic animals, i t would appear to be in the dog that snake bite presents the biggest problem (Clarke and Clarke 1975). Whilst there are individual case reports (Fethers 1943; Dickinson 1953; Keep 1957; Gordon 1958) and reviews (Trinca 1959; Lewis 1978) of snake bite in dogs in Australia, a large series of such cases has not been reported previously. This paper records the clinical signs, management and outcome of 80 cases of snake bite in the dog.
The 80 cases made up 0.3% of the total dogs brought to the hospital for treatment, excluding speys, castrations and vaccinations. Fifty-one dogs (64%) were reported to have been seen in contact with a snake. Many owners witnessed their dog either finding a snake and being bitten or fighting a snake. Sometimes the dog had been found with a dead snake. Thirty-two Tiger snakes and 3 Brown snakes were positively identified. Identification of the species in the remainder was
Materials and methods Snake bite \\as diagnowd in 80 dogs admitted to the Melbourne Uiiiveinitp Hospital during the last 7 years. The breed di\tribution varied but >porting dogs figured prominently. 17 golden laboradors and their crosses, 7 cocker spanieh, and 7 pointers. There were ;dl males, 26 females and 10 speyed females. Their ages ranged from 2 months to 13 years with 27 cases two yearr old or younger. The average age was 3.6 years. The procedure adopted f o r the management, diagnosis and treatnieni \\a!, \imilar 10 that iised for snahe bite in cats and the details have becn published previously (Hill and Campbell 1Y78). A firm diagnosis of snake bite was made in each case from the presenting neurological features and one or more of [ l i e following: positive evidence of contact with a snake; prevailing hot lreathcr conditions favouring snake activity; the finding of snake bite-like puncture \\ounds in the skin of the patient; elevated p l a m a creatiniiie phosphokinase (CPK) levels. When the bite was not witnessed, a favourable responbe and recovery by the patient after receiving 3000 units of Tiger rnahe antiveiiene or both Tiger snake and 500 units of Brown snake antiveiiene wits raken to he confirmation of (he diagnobis. Atropine hulphate %as an additional and frequent trt'atmenl for t h c alfected d Three dogs sustained a second w a k e bite 7 , I I and 18 nioi after receiving their fir5r. Tw o dog\ \ecn cairyiiig dcad mi did not develop envenoniation and are ecludtrd f r o m the series.
'I'ABLE 1
82
Frequency of Clinical Signs in 80 Dogs with Snake Bite Sign Dilated pupils Anisocoria Pupil light reflex absent Pupil light reflex sluggish Depression with generalised muscle weakness Vomiting (reported or observed) Salivation Hindlimb ataxia Respiratory signs (panting, tachypnoea, dyspnoea) Total flaccid paralysis Isolated muscle tremors Quadriplegia Diarrhoea Pharyngeal, tongue or vocal chord paralysis Elevated rectal temperature Depressed rectal temperature Cyanosed mucous membranes
Times Recorded
61 1 50 15 48 45 40 31 31 20
19 8 4 4 21
13 8
.4usrra/ian Vereririar~.lourri;l/, V o l . 5 5 , Februar?, 1979
not possible. For dogs seen to be bitten, the time from bite to presentation at the hospital was a mean of 3.1 hours. The time lapse for all cases, from either the onset of illness in cases not seen to be bitten or :he actual snake bite, to admission into the hospital was a mean of 5.8 hours. The signs are given in Table 1 which shows that dilated pupils, absence or reduction of :he pupillary light reflex (PLR), depression with generalised muscle weakness, vomiting, salivation, respiratory signs and hindlimb ataxia were the most commonly observed. Table 2 records the frequency of clinical signs in 27 dogs seen to have been bitten and presented for treatment within one hour of the event. In this group the predominant clinical signs were similar, however in 6 cases the pupils were normal and in 8 a PLR was present. Snake bite puncture wounds were found in the skin of 8 dogs. There was little or no reaction at the site of the bites. On 3 occasions owners reported that their dog had collapsed dramatically and momentarily within seconds of receiving the snake bite and then recovered only subsequently to develop the typical signs of envenomation. Haematuria or haemoglobinuria/ myoglobinuria was observed in 19 cases. Plasma CPK values were estimated in 16 cases and were always elevated with a mean of 1271 mu/ml (range 137 to 5016 mu/ml). Appropriate antivenene was used, when the species of snake involved had been identified. Otherwise Tiger snake antivenene was given alone, or combined with Brown snake antivenene. Seventy-five cases received anti-venene therapy. Seventy were given 3000 units Tiger snake antivenene, 3 received 500 units Brown snake antivenene and 2 received both 3000 units and 500 units of Tiger and Brown snake antivenene respectively. One dog, known to have been bitten by a TABLE 2
Frequency of Clinical Signs in 27 Dogs Presented for Treatment within 1 Hour of Having Been Seen to be Either in contact with or Bitten by a Snake. Signs Frequency Salivation 21 18 Vomiting (seen or reported by owner) Depression 12 Hindlimb ataxia 16 8 Isolated muscle tremors Quadriplegia 2 Dilated pupils 20 1 Anisocoria Normal pupils 6 8 Pupil light reflex present Pupil light reflex absent 9 Pupil light reflex sluggish 10 Respiratory signs (panting, tachypnoea) 14 Atisfralian Vererinary .lourrial, Vol. 5 5 , February, 1979
Tiger snake 16 hours before treatment, received a n additional 1500 units of Tiger snake antivenene, when there was no clinical improvement 12 hours following the initial dose. Lactated Ringers fluid was given intravenously by drip routinely and maintained until a definite clinical improvement was observed. Atropine sulphate was frequently administered to control salivation. Further infrequent therapy was oxygen, antibiotic cover, corticosteroids and antihistamines. One dog found carrying a dead Tiger snake in its mouth, but not showing signs of envenomation, at the owner's insistence was given 3000 units Tiger snake antivenene a n d immediately developed a n anaphylactic reaction, which was successfully treated with adrenalin and corticosteroid therapy. Of the 75 cases receiving antivenene, 65 survived and recovered completely (87%). The recovery rate was 85% for the 47 cases either having known contact with or seen to be bitten by a snake and receiving antivenene. Recovery time varied from 8 hours to 6 days (mean of 36 hours). The mean recovery time for the dogs receiving antivenene within one hour of being bitten was 24 hours. Five dogs died before antivenene could be given to them. Complete flaccid paralysis, cyanosis, dyspnoea a n d h y p o t h e r m i a with rectal temperatures below 35" were consistent findings in these cases. Two had been bitten 24 hours previously and another 6 hours prior to presentation. The remaining t w o were brought to the clinic within one hour of the snake bite. Ten dogs died following antivenene therapy. Again these cases invariably presented in terminal collapse, cyanosed, dyspnoeic and hypothermic. Many of them had been either bitten or ill for a t least 12 hours but two cases were seen within a n hour of being bitten, and failed to respond to antivenene and supportive therapy. Three dogs bitten by Brown snakes and receiving Brown snake antivenene recovered. The two dogs given Tiger and Brown snake antivenene had been ill for over 12 hours before presentation. The bites were not witnessed. Both cases showed complete flaccid paralysis, dyspnoea and were hypothermic. One died, the other made a slow recovery over 4 days. Autopsies were performed on 8 cases. Puncture wounds were found in the skin of the head and forelimbs of 6 of the dogs. The wounds were accompanied by subcutaneous haemorrhage and slight oedema. There were no consistent gross findings. Occasionally congestion of the lungs and kidneys and haemoglobin/myoglobinuria were reported. Histologically, generalised acute and hyaline degeneration of skeletal and myocardial muscles were consistent findings. 83
30
2:
21
al
m ES al
: n 11
r jun
lul
aug
sep
oct
nov
Figure 1 Monthly ncidence of cases
Of
dec
Ian
'eb
mar apr
may
snakc bite In dogs
Sixty-seven cases (84To) occurred in the warmer months of the year between October a n d March (Figure 1 ) . Thirty-$even cases (46%) were in the months of December a n d January. Discussion
The location and environs of the University Veterinary Clinical Hospital a n d the p r e p o n d e r a n c e of T i g e r s n a k e s in t h e neighbourhood have been discussed previously (Hill and Campbell 1978). In this series of bites, 32 Tiger snakes were identified, making it possible to confirm the importance of this species of snake in the Werribee area. The majority of cases occurred in the summer months which is consistent with previous findings (Hill and Campbell 1978; Lewis 1978). A few dogs were bitten in the cooler months of the year, when warm changes in the prevailing weather encouraged snakes out of hibernation prematurely. Many more dogs were seen t o be either bitten by o r in contact with a snake (64%) compared to the cases of cat snake bite (16%). Consequently the illness o r bite-to-treatment time for dogs was much shorter (mean 5.8 hours) than for the cats (mean 21 hours). I n spite of this, the recovery rates for dogs a n d cats receiving antivenene were similar (dogs 87"10, cats 89%), a n d would appear to substantiate earlier findings that cats are very resistant to snake envenomation (Trinca 1959). Earty signs frequently reported were salivation and vomiting. Salivation was not recorded in the three cases of Brown snake bite, but with one of them vomiting occurred. Dilated pupils, unresponsive to light, were not present in all early cases of envenomation, a n d there is a danger of 84
misdiagnosis in such cases, more particularly where the snake bite is not witnessed. Consistently plasma CPK was highly elevated a n d proved to be a useful confirmatory laboratory aid in these cases. The composition of the Tiger snake venom has been discussed in a previous paper (Hill and Campbell 1978). Neurotoxin, myotoxin, a defibrinating factor a n d haemolysin components are probably responsible for the degeneration of skeletal muscle fibres, r-lease of CPK into the c i r c u I a t i o n , h a e m a t u r i a a n d h a e m og 1obi nuria/myoglobinuria. It must be emphasised that in Victoria in cases of animal snake bite where the identity of the snake is uncertain, both Tiger and Brown snake antivenene should be used for treatment. I t is only the preponderance of Tiger snakes i n the immediate environs of the University Veterinary Hospital which allows the use of Tiger snake antivenene alone for cases either not seen t~ be bitten o r where the species of snake is not identified. T h e recovery rate was good in patients receiving antivenene therapy. Signs necessitating a poor prognosis were complete flaccid paralysis, dyspnoea a n d a sub-normal temperature. Generally these dogs had been ill f o r over 12 hours. However on occasions cases were presented with this triad of signs within an hour of being bitten and one can only assume that they received a very efficient bite a n d a large volume of venom. For snake bite in cats, n o correlation was possible between the bite-to-treatment period a n d the treatment t o full recovery period (Hill a n d Campbell 1978). In this series of dogs it was possible to demonstrate that recovery was quicker when treatment was administered within one hour of the bite. Antivenene is prepared by hyperimmuniying horses with appropriate snake venom. An anaphylactic reaction occurred in one dog inimediately following the administration of the heterologous serum, indicating that it is advisable to administer either adrenalin o r a n antihistamine prior to giving antivenene. At least i t is essential that these drugs a r e to hand u h e n antivenene is given. T h e three dogs in this series receiving a second snake bite months after receiving their first were given adrenalin before the administration of repeat antivenene therapy.
I
Acknowledgments erateful to former and present interns in the I k p a r t of Veterinary Clinical Sciences for supplying nian) of the
an1
iiiciit
case details, to Dr J. S. M'ilhinson and hi, .;taff lor u r i n a l y w 5 and tlic C P h estimations a n d to meinber\ of the Department 0 1 Paraclinical Science\ for the autop5) report
