Camp. Biockm. Physiol.Vol. lOlA, No. 4, pp. 701-703, 1992 Printed in Great Britain
0300-9629/92 $5.00 + 0.00 Pcrgamon Press plc
ELEMENTS OF ACID-BASE BALANCE IN THE EUROPEAN BISON, BISON BONASUS (L.) IN THE WINTER PERIOD JANUSGILL Department of Vertebrate Animal Physiology, University of Warsaw, Zwirki i Wigury 93; 02-089 Warsaw, Poland (Received 2 Augusr 1991) Abstract-l. In the blood of 65 European bison divided into four groups (Group 1, 0-3-year-old males; Group 2, 0-3-year-old females; Group 3, mature bulls, over 3 years old; Group 4, mature cows, over 3 years old) the values of pH, pCOr, PO,, base excess and bicarbonate level were studied. 2. The studies were carried out in winter months, from mid-December to mid-April. 3. No significant differences in parameters studied were found between young males and females. 4. All indices found in mature bulls and cows showed si~fi~nt differences between all other groups. 5. Most of parameters examined here in European bison are comparable with those found in other big ruminants.
INTRODUCI’ION The European bison is the only large animal of Europe which has survived to the present day. Very
little is known about its physiolo~. It is known from old books (Karcov, 1903; Wr&blewski, 1927) that during hunting on a tlat and open area no horse could reach the European bison. The ability of bisons to tolerate acidification, and thus long term physical effort, confirm experiments made on the loading of bisons with exogenous lactic acid (Gill, 1967, 1970). These experiments showed a very high resistance of the bison to toxic chemical factors, but a quite different feature of the bison metabolism showed the course of the foot-and-mouth disease in reserves of bisons of southern Poland in 1953. The course of that disease was as quick as 1 or 2 hr, from the first salivation. The rather low metabolic rate of the bison shows the low value of the F index-an index of the oxygen carrying capacity of the blood unit. It is lower than that in any other mammal (Gill, 1987). This indicates a low capacity of bison blood for trans~~ation of oxygen. Ad~tionally, the F index is seasonally cyclic only in mature bison cows (Gill, 1989). In other groups of bison it is acyclic in the course of a year. The red blood cell number is slightly higher in European bison than in domestic cattle and in American bison (Gill, 1989b; Walk, 1983). It is similar to the haemoglobin count. Mazur ef al. (1986), studying the primary structure of haemoglobins stated that: (a) globin chains of the European bison haemoglobin are comparable with those of the American bison and domestic cattIe; (b) haemoglobin of the European bison has a low affinity to oxygen. Haines et al. (1977) also stated that haemoglobin of the American bison has a low affinity to oxygen and thus high ability to transport the oxygen to tissues. This low affinity for oxygen facilitates its liberation, especially in working muscles. On that basis Mazur et al. confirm the idea of Gill (1967) 701
that both European and American bisons are well adapted to prolonged running, or strong physical effort. In this discussion one of the valid elements is the behaviour of pH, pressures of respiratory gases and balance of acid-base values in the whole blood of bison. In a short communication (Gill, 1989a) it was shown that in 26 European bison studied in winter, the differences in gas tensions were small between young and mature animals, as well as between sexes. This data needs to lx extended to a larger number of specimens. The number of European bison living as the freeranging herd in Bialowieia Primeval Forest steadily increases. To keep the population size within well determined limits some of them are culled. This allowed for the collection of blood at the time of shooting. In the present paper it was of interest, therefore, to study the acid-base balance problems in a great number of bisons, and to compare the indices of this balance with other parameters of the bison metabolism. MATRRIALS ANDMETHODS All examined bison were selected and shot during the period 1987-1991, between 13th December and 12th April. All 65 European bison were divided into four groups: Group 1, sexually immature males, O-3 years old; Group 2, immature females, O-3 years old; Group 3, mature bulls, over 3 years of age; Group 4, mature cows, over 3 years old. The blood was taken from the jugular vein cut immediately after the animal was shot. Rlood gases and pH were measured at 37°C on a direct leading electrode system (EEL Corning 165, USA.) along with HCO; levels being computed by the apparatus. All data were analysed statistically according to the Student’s r-test (Gctaba, 1977). The data for-separate groups were compared. The statistically significant differences (P c 0.05) are indicated by S and not significant by NS.
702
JANUSZ GILL Table 1. Values of acid-base balance in the European bison, &son bonacur (L.) Group
Animals
I
Males, O-3 years (min-max) Females, O-3 years (min-max) Bulls, adult (min-max) Cows, adult (min-maxi
2 3 4
N
PH
pco, mmH8
16
7.31 + 0.025 (7.12-7.50) 7.32 f 0.020 (7.1 l-7.45) 7.37 * 0.019 (7.33-7.44) 7.30 + 0.015 (7.13-7.431
63.48 + 3.71 (43.0-90.8) 62.28 i 3.05 (44.0-92.0) 52.68 It 5.37 (44.0-73.0) 59.12 + 2.19 (43.0-84.0)
22 5 22
BEb mmol~i
HCO; mmot/t
+3.27 f 1.24 (-4%+ 11.2) +3.9.5 f 1.00 (-7.5-+ 11.0) +4.00 f 1.81 (-0.2-+ 10.0) f0.89 + 1.13 1-9.2-+8.0)
31.23 + 1.14 (25.0-41.4) 31.73 + 0.95 (20.0-38.3) 30.18 f 2.31 (25.8-38.5) 28.78 & 1.09 119.4-36.5~
PO2 m=& 25.71& 3.46 (10.0-68.0) 24.58 + 1.79 (13.0-48.0) 22.58 f I.52 (18.0-26.0) 22.84 k 1.79 110.0-37.0~
Values are mean + SE.
RESULTS
are NS. Between all other groups the values are S (P < 0.001).
The mean values of pH of the venous blood changed from 7.31 + 0.025 (young males) to 7.37 k 0.019 (mature bulls) (Table 1). As it is seen from Fig. l--only within young bison pH values
CO2 pressure The mean pC0, changed from 52.68 k 5.37 mmHg (bulls) to 63.48 + 3.71 mmHg (young males). The individual variations are rather high, especially great in young females (44.0-92.0 mmHg) (Table 1). Again, the values between young animals are NS (Fig. l), but between other groups are S, (P < 0.001-0.01). These pressures are distinctly lower in mature bulls than in other groups.
pH values
1
Gr.1
Gr.IV
Gr.II
z40 x
7.30
7.20
O2 pressure The mean p0, changed from 22.58 & 1.52 mmHg. (bulls) to 25.77 + 3.46 mmHg (young males) (Table 1). The individual variations were the highest in young males (10.~8.O~Hg). Similarly as with pC0, here the values between young bison were NS, (Fig. 1) and between all other groups they were S, (P < 0.01-0.05).
64SO-
Base excess (BEb)
These values changed from (cows) to 4.00 f 1.81 mmol/I The individual variations were is seen in females: -7.5-l 1.0, 8.0mmol/l, cows. As it is seen values were NS between young male groups. The lowest level of cows. Bicarbonate (HCO;)
0.89 j, 1.13 mmol/l {bulls) (Table 1). rather high, which young ones; -9.2from Fig. l-these animals and within BEb showed mature
level
The mean values of HCO, changed from 28.78 + 1.09 mmol/l in cows to 31.73 If: 0.95 mmolfl in young females, The highest individual variations were in young females (20.0-38.3 mmol/I) (Table I). The values were S only between females and between young males (Group 1) and mature cows (Group 4), with P < 0.001.
32 30
DISCUSSION
28 26 / s..
Fig. 1. The values between means of
PC
0.001;
. . p
0300-9629/92 $5.00 + 0.00 Pcrgamon Press plc
ELEMENTS OF ACID-BASE BALANCE IN THE EUROPEAN BISON, BISON BONASUS (L.) IN THE WINTER PERIOD JANUSGILL Department of Vertebrate Animal Physiology, University of Warsaw, Zwirki i Wigury 93; 02-089 Warsaw, Poland (Received 2 Augusr 1991) Abstract-l. In the blood of 65 European bison divided into four groups (Group 1, 0-3-year-old males; Group 2, 0-3-year-old females; Group 3, mature bulls, over 3 years old; Group 4, mature cows, over 3 years old) the values of pH, pCOr, PO,, base excess and bicarbonate level were studied. 2. The studies were carried out in winter months, from mid-December to mid-April. 3. No significant differences in parameters studied were found between young males and females. 4. All indices found in mature bulls and cows showed si~fi~nt differences between all other groups. 5. Most of parameters examined here in European bison are comparable with those found in other big ruminants.
INTRODUCI’ION The European bison is the only large animal of Europe which has survived to the present day. Very
little is known about its physiolo~. It is known from old books (Karcov, 1903; Wr&blewski, 1927) that during hunting on a tlat and open area no horse could reach the European bison. The ability of bisons to tolerate acidification, and thus long term physical effort, confirm experiments made on the loading of bisons with exogenous lactic acid (Gill, 1967, 1970). These experiments showed a very high resistance of the bison to toxic chemical factors, but a quite different feature of the bison metabolism showed the course of the foot-and-mouth disease in reserves of bisons of southern Poland in 1953. The course of that disease was as quick as 1 or 2 hr, from the first salivation. The rather low metabolic rate of the bison shows the low value of the F index-an index of the oxygen carrying capacity of the blood unit. It is lower than that in any other mammal (Gill, 1987). This indicates a low capacity of bison blood for trans~~ation of oxygen. Ad~tionally, the F index is seasonally cyclic only in mature bison cows (Gill, 1989). In other groups of bison it is acyclic in the course of a year. The red blood cell number is slightly higher in European bison than in domestic cattle and in American bison (Gill, 1989b; Walk, 1983). It is similar to the haemoglobin count. Mazur ef al. (1986), studying the primary structure of haemoglobins stated that: (a) globin chains of the European bison haemoglobin are comparable with those of the American bison and domestic cattIe; (b) haemoglobin of the European bison has a low affinity to oxygen. Haines et al. (1977) also stated that haemoglobin of the American bison has a low affinity to oxygen and thus high ability to transport the oxygen to tissues. This low affinity for oxygen facilitates its liberation, especially in working muscles. On that basis Mazur et al. confirm the idea of Gill (1967) 701
that both European and American bisons are well adapted to prolonged running, or strong physical effort. In this discussion one of the valid elements is the behaviour of pH, pressures of respiratory gases and balance of acid-base values in the whole blood of bison. In a short communication (Gill, 1989a) it was shown that in 26 European bison studied in winter, the differences in gas tensions were small between young and mature animals, as well as between sexes. This data needs to lx extended to a larger number of specimens. The number of European bison living as the freeranging herd in Bialowieia Primeval Forest steadily increases. To keep the population size within well determined limits some of them are culled. This allowed for the collection of blood at the time of shooting. In the present paper it was of interest, therefore, to study the acid-base balance problems in a great number of bisons, and to compare the indices of this balance with other parameters of the bison metabolism. MATRRIALS ANDMETHODS All examined bison were selected and shot during the period 1987-1991, between 13th December and 12th April. All 65 European bison were divided into four groups: Group 1, sexually immature males, O-3 years old; Group 2, immature females, O-3 years old; Group 3, mature bulls, over 3 years of age; Group 4, mature cows, over 3 years old. The blood was taken from the jugular vein cut immediately after the animal was shot. Rlood gases and pH were measured at 37°C on a direct leading electrode system (EEL Corning 165, USA.) along with HCO; levels being computed by the apparatus. All data were analysed statistically according to the Student’s r-test (Gctaba, 1977). The data for-separate groups were compared. The statistically significant differences (P c 0.05) are indicated by S and not significant by NS.
702
JANUSZ GILL Table 1. Values of acid-base balance in the European bison, &son bonacur (L.) Group
Animals
I
Males, O-3 years (min-max) Females, O-3 years (min-max) Bulls, adult (min-max) Cows, adult (min-maxi
2 3 4
N
PH
pco, mmH8
16
7.31 + 0.025 (7.12-7.50) 7.32 f 0.020 (7.1 l-7.45) 7.37 * 0.019 (7.33-7.44) 7.30 + 0.015 (7.13-7.431
63.48 + 3.71 (43.0-90.8) 62.28 i 3.05 (44.0-92.0) 52.68 It 5.37 (44.0-73.0) 59.12 + 2.19 (43.0-84.0)
22 5 22
BEb mmol~i
HCO; mmot/t
+3.27 f 1.24 (-4%+ 11.2) +3.9.5 f 1.00 (-7.5-+ 11.0) +4.00 f 1.81 (-0.2-+ 10.0) f0.89 + 1.13 1-9.2-+8.0)
31.23 + 1.14 (25.0-41.4) 31.73 + 0.95 (20.0-38.3) 30.18 f 2.31 (25.8-38.5) 28.78 & 1.09 119.4-36.5~
PO2 m=& 25.71& 3.46 (10.0-68.0) 24.58 + 1.79 (13.0-48.0) 22.58 f I.52 (18.0-26.0) 22.84 k 1.79 110.0-37.0~
Values are mean + SE.
RESULTS
are NS. Between all other groups the values are S (P < 0.001).
The mean values of pH of the venous blood changed from 7.31 + 0.025 (young males) to 7.37 k 0.019 (mature bulls) (Table 1). As it is seen from Fig. l--only within young bison pH values
CO2 pressure The mean pC0, changed from 52.68 k 5.37 mmHg (bulls) to 63.48 + 3.71 mmHg (young males). The individual variations are rather high, especially great in young females (44.0-92.0 mmHg) (Table 1). Again, the values between young animals are NS (Fig. l), but between other groups are S, (P < 0.001-0.01). These pressures are distinctly lower in mature bulls than in other groups.
pH values
1
Gr.1
Gr.IV
Gr.II
z40 x
7.30
7.20
O2 pressure The mean p0, changed from 22.58 & 1.52 mmHg. (bulls) to 25.77 + 3.46 mmHg (young males) (Table 1). The individual variations were the highest in young males (10.~8.O~Hg). Similarly as with pC0, here the values between young bison were NS, (Fig. 1) and between all other groups they were S, (P < 0.01-0.05).
64SO-
Base excess (BEb)
These values changed from (cows) to 4.00 f 1.81 mmol/I The individual variations were is seen in females: -7.5-l 1.0, 8.0mmol/l, cows. As it is seen values were NS between young male groups. The lowest level of cows. Bicarbonate (HCO;)
0.89 j, 1.13 mmol/l {bulls) (Table 1). rather high, which young ones; -9.2from Fig. l-these animals and within BEb showed mature
level
The mean values of HCO, changed from 28.78 + 1.09 mmol/l in cows to 31.73 If: 0.95 mmolfl in young females, The highest individual variations were in young females (20.0-38.3 mmol/I) (Table I). The values were S only between females and between young males (Group 1) and mature cows (Group 4), with P < 0.001.
32 30
DISCUSSION
28 26 / s..
Fig. 1. The values between means of
PC
0.001;
. . p
