- Email: [email protected]
Blood and Plasma Volumes of Neonatal Pigs Expressed Relative to Bodyweight and Total Body Water
Br. vet.
J. (1973),
129.
58 3
BLOOD AND PLASMA VOLUMES OF NEONATAL PIGS EXPRESSED RELATIVE TO BODYWEIGHT AND TOTAL BODY WATER By R.
POWNALL
*
AND
R. G.
DALTONt
Department of Veterinary Clinical Studies, The University of Liverpool SUMMARY
Plasma and blood volume, venous haematocrit and total body water content were determined at birth and at intervals thereafter in piglets up to 30 days old. Significant changes with age were observed in these parameters. An analysis was made of the merits of expressing body fluid volumes relative to bodyweight or total body water. INTRODUCTION
Previous workers have expressed blood and plasma volumes of piglets as percentages of bodyweight (McCance & Widdowson, 1959; Talbot & Swenson, 1963; Ramirez, Miller, Ullrey & Roeffer, 1963; Kunesh, 1966). However, Pownall & Dalton (1969) considered this reference base unsuitable for assessing changes in body fluid volumes because the adiposity of pigs varies widely with age, growth rate or disease. At birth, piglets have very little body fat yet in the first month of life a considerable proportion of their rapidly acquired increase in bodyweight is associated with fat deposition (Manners & McCrea, 1963; Wood & Groves, 1965). Fat, being relatively anhydrous, may by its contribution to bodyweight but relative lack of contribution to body fluid content obscure age related changes in volumes of the body fluids if these are expressed relative to bodyweight. In this study therefore, plasma and blood volumes, measured immediately prior to total body water determination in piglets 0-30 days old, are presented and analysed as ml/kg bodyweight or ml/litre total body water. MATERIALS AND METHODS
Experimental animals and their management Measurements were made on 58 cross-bred piglets reared with their sows, in wooden huts located in concrete pens. Creep feed was given when the piglets were 20 days old. Clinically the piglets were healthy and low-weight-forPresent addresses: Newmarket, Suffolk; Place, E.dinburgh 8.
* Animal
H ealth Trust, Small Animals Centre, Lanwades Park, Kennett,
t Department of Surgery, The University of Edinburgh Medical School, Teviot
BRITISH VETERINARY JOURNAL, 129, 6
age ("runt") piglets were excluded intentionally from the study. Piglets were given 200 mg of elemental iron * by subcutaneous injection when three days old, with the exception of those piglets which were studied on the fifth day of life. To avoid the adverse effects oflipaemia on the colorimetric determination of dye concentration (Allen, r953), piglets were removed from the sow approximately one and a half hours before plasma volume measurements were made. Bodyweights were measured on an Averyt r302 BCD balance.
Determination ofplasma and blood volume With the piglets restrained manually in a dorsal recumbant position, a 20 BWG needle connected to two syringes by a two-way tap was inserted through the lateral chest wall into the heart; ro ml of blood was then withdrawn into one syringe containing heparin. Then, after turning the tap, a volume of the T.r824- dye solution was injected rapidly. A o·r g per cent T.r824-t in physiological saline solution was used in approximately 5-ml quantities in piglets up to five days old and in ro-ml quantities for ro-day-old piglets. Older piglets were injected with 5 ml of a 0·2 g per cent solution. The amount of dye solution injected was determined from the weight of the tap, needle and syringe before and after injection. Studies made on the disappearance rate of injected T.r824- showed that the plasma dye concentration IO minutes after injection was similar to that obtained by extrapolating the dye disappearance curve to a theoretical zero time. Routinely, therefore, plasma volume was determined from the plasma dye concentration in a 5-ml heparinized blood sample collected from the anterior vena cava IO minutes after dye was injected. Mter collection of this sample the piglets were sacrificed by intravenous injection of pentobarbitone sodium.§ Their thoracic and pericardial cavities were then examined and in the event of dye being found in these sites, indicating a faulty injection, the result from the piglet was excluded. Handling of blood samples, the determination of packed cell volume (PCV) and the storage of plasma samples has been described previously (Pownall, r 970). The dye concentration in the test sample was determined colorimetrically by comparing it to that of a known concentration of dye added to plasma collected from the same piglet prior to injecting the T.r824- (Dalton & Fisher, r96r). Photometric measurements were made using an Ilford 607 filter in an E.E.L. Colorimeter. II Blood volumes were calculated using the formula: roo
X
Plasma volume (ml)
Blood volume (ml) r 00- (0·95 • Imposil
200,
Fisons, Cambridge.
t W. T. Avery Ltd., Liverpool.
:j: Gurr Ltd., London. § Euthatal. May & Baker Ltd., Dagenham. II Evans Electroselenium Ltd., Halstead.
X
PCV)
BLOOD AND PLASMA VOLUMES OF NEONATAL PIGS
585
The correction factor of 0'95 was included to allow for a 5 per cent trapped plasma volume in the packed cell column. This has been shown to be appropriate in pigs irrespective of age and haematocrit value (Anderson, 1970). In this calculation no allowance has been made for the difference between the whole body and venous haematocrit. It was considered that with the excitement aroused by handling, the whole body haematocrit:sample haematocrit ratio would be approximately unity in our experimental subjects. Mter sacrifice, the piglets' body water was determined by desiccation of the cadaver at 78·0 °C until a constant dry weight was attained (Pownall, 1972). RESULTS
Table I contains mean ± S.D. values at the selected ages for bodyweight and body water in mlJkg bodyweight. Plasma and blood volumes are expressed conventionally as mlJkg bodyweight in Table II and in terms of mlJlitre body water in Table III. TABLE I BODY WATER A S ML/ KG OF BODYWEIGHT
Age
Mean At birth [2 hours 24 hours 48 hours 72 hours [20 hours 10 days [5 days 20 days 30 days
Body water (ml/kg bodyweight)
Bodyweight (kg )
No. of piglets
1'11 1'3 6 1'43 1'28 1'42 2'09 3'26 5' 6 4 6'3[ 8'40
7 5 5 6 6 6 8 4 5 6
± S.D.
Mean
± S.D .
81 7 800 802 809 790 757 774 73 2 720 70 9
0'[9 0'37 0'54 0'35 0'3 1 0'5 8 0' 77 0'9 0 ['33 0'94
II
3 9 6 6 [6 30 27 3 I[
TABLE II HAEMATOCRIT AND PLASMA AND BLOOD VOL U ME EXPRESSED AS ML/KG BODYWEIGHT
Age
No. of piglets
Haematocrit (%) Mean
At birth [2 hours 24 hours 48 hours 72 hours [20 hours 10 days [5 days 20 days 30 days
7 5 5 6 6 6 8 4 5 6
41 34 34 28 30 26 33 35 32 34
± S.D. 4 4 5 4 4 4 5 3 2 3
Plasma volume (ml/kg bodyweight ) Mean 64 73 7[ 71 73 75 82 65 61 58
Blood volume (ml/kg bodyweight ) Mea1l
± S.D.
8 8 8
103 107 107
[0
[00
8 7 9 [5 7 5
[00 [00 118 98 87 86
[0 [0 7 9 5 8 [0 6 9 8
± S.D.
586
BRITISH VETERINARY JOURNAL,
129,
6
TABLE III PLASMA AND BLOOD VOLUME EXPRESSED AS MLILITRE BODY WATER
Age
No. of piglets
Plasma volume (mil litre body water) Mean
At birth
hours 24 hours 48 hours 72 hours 120 hours 10 days 15 days 20 days 30 days 12
7 5 5 6 6 6 8 4 5 6
± S .D.
81 91 89 89 92 99 109 90 84 81
10
10 II
12 10 II
14 8 10 7
Blood volume (millitre body water) Mean
12 9 134 134 126 12 7 141 157 135 123 120
±
S.D.
13 13 12 12 8 14 15 8 15 II
DISCUSSION
The results shown in Table II, expressing plasma and blood volumes in ml/kg bodyweight, are comparable to values obtained by the previous workers cited. Plasma volumes per unit ofbodyweight increased by approximately II per cent in the first 24 hours of life, though statistically the difference between the mean value at birth and 24 hours was not significant (P > o· I). McCance & Widdowson (1959) recorded a 47 per cent increase in plasma volume from birth to 24 hours, and Ramirez et at. (1963) a 31 per cent increase. It is apparent from the plasma volume values presented in Tables II and III, and from the observations of Ramirez et at. (1963), that most of the increase in volume occurs within the first 12 hours after birth. Mean values recorded at 10 days for plasma and blood volumes expressed in ml/kg bodyweight (Table II) or as ml/litre body water (Table III) were higher than mean values obtained at birth or 30 days with at least a 5 per cent level of significance. A fall in plasma sodium, potassium and inorganic phosphate concentrations and osmolality was observed in piglets from birth to 6- 12 hours (Pownall, 1970). From birth to 12 hours there is also a significant (P < 0'05 ) fall in haematocrit (Table II). A similar fall in the concentration of plasma electrolytes and formed elements was recorded by McEwan, Fisher & Selman (1968) in calves fed either milk or colostrum from birth. These findings suggest that in both piglets and calves, plasma volume expansion is the r esult of dilution of the initial plasma volume by hypotonic fluid. In view of findings on the changes in the relative proportions of the body fluids of piglets within 24 hours of birth, iLseems probably that the fluid taken up from colostrum is distributed unevenly between the various body fluid compartments (Pownall, 197 2 ) . The results presented in Table I show that with increasing age, body water expressed in terms of ml/kg decreased. This presumably reflects the effect of body fat deposition on the expression of body fluid volumes per unit of bodyweight as outlined in the introduction. The effect on the changes with age in plasma volume when expressed relative to bodyweight and body water are of
BLOOD AND PLASMA VOLUMES OF NEONATAL PIGS
587
interest. Thus, taking from Table II, the average plasma volume on days 1-3 oflife as 72 ml/kg bodyweight and on the 20- 30th days as 60 ml/kg bodyweight, 72 - 60 this represents a decrease in volume equivalent to - - - X 100 = 16'7 per cent.
72
Alternatively, taking from Table III the average plasma volume on days 1- 3 of life as go ml/litre body water and as 83 ml/litre body water on the 20- 30th 9 0 -:83 days, this represents a decrease of only -. - - X 100 = 7.8 per cent.
90
In conclusion, it appears advisable if assessing changes in the plasma and blood volumes of piglets whose adiposity may vary in relation to age, growth rate and disease, to ad~pt body water as the basis of reference.
ACKNOWLEDGEMENTS
This study was supported by the Meat and Livestock Commission and the Agricultural Research Council. The authors gratefully acknowledge the technical assistance of Mrs Eileen McKerracher and Mrs Anne Claridge and the advice of Professor R. J. Fitzpatrick and Dr E. C. Pickering.
RE.F.E.REN.CES- . . . ... _ ._
ALLEN, T. H. (1953). Am. J. Physiol. 175,227· ANDERSON, D. M. (1970) . J. compo Path. 80,1 63 . DALTON, R. G. & FISHER, E. W. (1961). Br. vet. J. 117, 115. KUNESH, J. P. (1966) . M.Sc. Thesis. Ames: Iowa State University. MANNERS, M.J. & MCCREA, M. R. (1963). Br. J. Nutr. 17,495. MCCANCE, R . A. & WIDDOWSON, E. M. (1959) . J. Physiol. , Lond. 145,547. McEwAN, A . D. , FISHER, E. W . & SELMAN, I. E. (1968). R es. vet. Sci. 9,284. POWNALL, R. (1970). Br. vet. J. 126, 465. POWNALL, R. ( 1972) . Ph.D. Thesis, University of Liverpool. POWNALL, R. & DALTON, R. G. (1969). Proc. 1St into Congr. Pig vet. Soc., Cambridge. RAMIREZ, C. G., MILLER, E. R ., ULLREY, D. E. & HOEFFER, J . A. (1963). J. Anim. Sci. 22, 1068. TALBOT, R. B. & SWENSON, M. J. (1963) . Am. J. vet. Res. 24,467. WOOD, A.J. & GROVES, T. D. D. (1965). Can. J. An. Sci. 45, 8. (Accepted for -publication 15 February 1973)
Vobunes sanguin et plasmatique de pores nouveaux-nes expriInes par rapport au poids corporel et a l'eautotaleorporelle (Pownall et Dalton) ResUIl1e. On determina chez des porcelets a la naissance et par la suite a intervalles jusqu'a l'age de 30 jours, Ie volume plasmatique et sanguin, l'hematocrite veineux et Ie volume d'eau total~ corporelle. Des variations significatives de ces parametres furent observes avec l'age. On fit une analyse des avantages a exprimer les volumes liquidiens corporels par rapport au poids . corpore! e~ a l'eau totale corporelle.
S88
BRITISH VETERINARY JOURNAL, 129,6
Blu~
und Plasmavolwnen bel neugeborenen Ferkeln in Beziehung zwn Korpergewicht und GeslUlltwassergehalt des Korpers (Pownall und Dalton) Zusauunenfassung. Unmittelbar nach dem Wurf und in Intervallen danach wurden 30 Tage lang bei Ferkeln Plasmaund Blutvolumen, venose Haematokritwerke und der Gesamtwassergehalt des Korpers festgestellt. Signifikante Anderungen wurden entsprechen dem Alter in diesen Parametern beobachtet. Die Vorzuge der Beschreibung des Korperflussigkeitsvolumens in Beziehung zum Gewicht oder Gesamtwassergehalt des Korpers wurden analysiert. VolUmenes de la sangre y plasma de cerdos neonatales expresados en relaci6n a peso corporal y al agua total del cuerpo (Pownall y Dalton) Reswnen. Se determinaron el volumen de sangre y plasma, hemat6crito venoso yel contenido total de agua corporal de lechones en el momenta de nacer y despues a various intervalos hasta los 30 dias. Se observaron cambios en estos parametros a medida que los lechonea avanzaron en edad. Se efectu6 u analisis de los meritos de expresar los volumenes corporales de flUido en relaci6n al peso corporal 0 agua total del cuerpo.
THE GEORGE FLEMING PRIZE This annual prize for the best article published in the journal will be awarded this year to W. A. Watson, S. Terlecki, D. S. P. Patterson, D. Sweasey, C. Nancy Herbert and]. T. Done for their paper on "Experimentally Produced Progressive Retinal Degeneration (Bright Blindness) in Sheep", which appeared in the September 1972 issue of the journal. The prize was instituted in 1965 to signalize the ninetieth year of publication of the British Veterinary Journal, and to honour its founder, Professor George Fleming.
J. (1973),
129.
58 3
BLOOD AND PLASMA VOLUMES OF NEONATAL PIGS EXPRESSED RELATIVE TO BODYWEIGHT AND TOTAL BODY WATER By R.
POWNALL
*
AND
R. G.
DALTONt
Department of Veterinary Clinical Studies, The University of Liverpool SUMMARY
Plasma and blood volume, venous haematocrit and total body water content were determined at birth and at intervals thereafter in piglets up to 30 days old. Significant changes with age were observed in these parameters. An analysis was made of the merits of expressing body fluid volumes relative to bodyweight or total body water. INTRODUCTION
Previous workers have expressed blood and plasma volumes of piglets as percentages of bodyweight (McCance & Widdowson, 1959; Talbot & Swenson, 1963; Ramirez, Miller, Ullrey & Roeffer, 1963; Kunesh, 1966). However, Pownall & Dalton (1969) considered this reference base unsuitable for assessing changes in body fluid volumes because the adiposity of pigs varies widely with age, growth rate or disease. At birth, piglets have very little body fat yet in the first month of life a considerable proportion of their rapidly acquired increase in bodyweight is associated with fat deposition (Manners & McCrea, 1963; Wood & Groves, 1965). Fat, being relatively anhydrous, may by its contribution to bodyweight but relative lack of contribution to body fluid content obscure age related changes in volumes of the body fluids if these are expressed relative to bodyweight. In this study therefore, plasma and blood volumes, measured immediately prior to total body water determination in piglets 0-30 days old, are presented and analysed as ml/kg bodyweight or ml/litre total body water. MATERIALS AND METHODS
Experimental animals and their management Measurements were made on 58 cross-bred piglets reared with their sows, in wooden huts located in concrete pens. Creep feed was given when the piglets were 20 days old. Clinically the piglets were healthy and low-weight-forPresent addresses: Newmarket, Suffolk; Place, E.dinburgh 8.
* Animal
H ealth Trust, Small Animals Centre, Lanwades Park, Kennett,
t Department of Surgery, The University of Edinburgh Medical School, Teviot
BRITISH VETERINARY JOURNAL, 129, 6
age ("runt") piglets were excluded intentionally from the study. Piglets were given 200 mg of elemental iron * by subcutaneous injection when three days old, with the exception of those piglets which were studied on the fifth day of life. To avoid the adverse effects oflipaemia on the colorimetric determination of dye concentration (Allen, r953), piglets were removed from the sow approximately one and a half hours before plasma volume measurements were made. Bodyweights were measured on an Averyt r302 BCD balance.
Determination ofplasma and blood volume With the piglets restrained manually in a dorsal recumbant position, a 20 BWG needle connected to two syringes by a two-way tap was inserted through the lateral chest wall into the heart; ro ml of blood was then withdrawn into one syringe containing heparin. Then, after turning the tap, a volume of the T.r824- dye solution was injected rapidly. A o·r g per cent T.r824-t in physiological saline solution was used in approximately 5-ml quantities in piglets up to five days old and in ro-ml quantities for ro-day-old piglets. Older piglets were injected with 5 ml of a 0·2 g per cent solution. The amount of dye solution injected was determined from the weight of the tap, needle and syringe before and after injection. Studies made on the disappearance rate of injected T.r824- showed that the plasma dye concentration IO minutes after injection was similar to that obtained by extrapolating the dye disappearance curve to a theoretical zero time. Routinely, therefore, plasma volume was determined from the plasma dye concentration in a 5-ml heparinized blood sample collected from the anterior vena cava IO minutes after dye was injected. Mter collection of this sample the piglets were sacrificed by intravenous injection of pentobarbitone sodium.§ Their thoracic and pericardial cavities were then examined and in the event of dye being found in these sites, indicating a faulty injection, the result from the piglet was excluded. Handling of blood samples, the determination of packed cell volume (PCV) and the storage of plasma samples has been described previously (Pownall, r 970). The dye concentration in the test sample was determined colorimetrically by comparing it to that of a known concentration of dye added to plasma collected from the same piglet prior to injecting the T.r824- (Dalton & Fisher, r96r). Photometric measurements were made using an Ilford 607 filter in an E.E.L. Colorimeter. II Blood volumes were calculated using the formula: roo
X
Plasma volume (ml)
Blood volume (ml) r 00- (0·95 • Imposil
200,
Fisons, Cambridge.
t W. T. Avery Ltd., Liverpool.
:j: Gurr Ltd., London. § Euthatal. May & Baker Ltd., Dagenham. II Evans Electroselenium Ltd., Halstead.
X
PCV)
BLOOD AND PLASMA VOLUMES OF NEONATAL PIGS
585
The correction factor of 0'95 was included to allow for a 5 per cent trapped plasma volume in the packed cell column. This has been shown to be appropriate in pigs irrespective of age and haematocrit value (Anderson, 1970). In this calculation no allowance has been made for the difference between the whole body and venous haematocrit. It was considered that with the excitement aroused by handling, the whole body haematocrit:sample haematocrit ratio would be approximately unity in our experimental subjects. Mter sacrifice, the piglets' body water was determined by desiccation of the cadaver at 78·0 °C until a constant dry weight was attained (Pownall, 1972). RESULTS
Table I contains mean ± S.D. values at the selected ages for bodyweight and body water in mlJkg bodyweight. Plasma and blood volumes are expressed conventionally as mlJkg bodyweight in Table II and in terms of mlJlitre body water in Table III. TABLE I BODY WATER A S ML/ KG OF BODYWEIGHT
Age
Mean At birth [2 hours 24 hours 48 hours 72 hours [20 hours 10 days [5 days 20 days 30 days
Body water (ml/kg bodyweight)
Bodyweight (kg )
No. of piglets
1'11 1'3 6 1'43 1'28 1'42 2'09 3'26 5' 6 4 6'3[ 8'40
7 5 5 6 6 6 8 4 5 6
± S.D.
Mean
± S.D .
81 7 800 802 809 790 757 774 73 2 720 70 9
0'[9 0'37 0'54 0'35 0'3 1 0'5 8 0' 77 0'9 0 ['33 0'94
II
3 9 6 6 [6 30 27 3 I[
TABLE II HAEMATOCRIT AND PLASMA AND BLOOD VOL U ME EXPRESSED AS ML/KG BODYWEIGHT
Age
No. of piglets
Haematocrit (%) Mean
At birth [2 hours 24 hours 48 hours 72 hours [20 hours 10 days [5 days 20 days 30 days
7 5 5 6 6 6 8 4 5 6
41 34 34 28 30 26 33 35 32 34
± S.D. 4 4 5 4 4 4 5 3 2 3
Plasma volume (ml/kg bodyweight ) Mean 64 73 7[ 71 73 75 82 65 61 58
Blood volume (ml/kg bodyweight ) Mea1l
± S.D.
8 8 8
103 107 107
[0
[00
8 7 9 [5 7 5
[00 [00 118 98 87 86
[0 [0 7 9 5 8 [0 6 9 8
± S.D.
586
BRITISH VETERINARY JOURNAL,
129,
6
TABLE III PLASMA AND BLOOD VOLUME EXPRESSED AS MLILITRE BODY WATER
Age
No. of piglets
Plasma volume (mil litre body water) Mean
At birth
hours 24 hours 48 hours 72 hours 120 hours 10 days 15 days 20 days 30 days 12
7 5 5 6 6 6 8 4 5 6
± S .D.
81 91 89 89 92 99 109 90 84 81
10
10 II
12 10 II
14 8 10 7
Blood volume (millitre body water) Mean
12 9 134 134 126 12 7 141 157 135 123 120
±
S.D.
13 13 12 12 8 14 15 8 15 II
DISCUSSION
The results shown in Table II, expressing plasma and blood volumes in ml/kg bodyweight, are comparable to values obtained by the previous workers cited. Plasma volumes per unit ofbodyweight increased by approximately II per cent in the first 24 hours of life, though statistically the difference between the mean value at birth and 24 hours was not significant (P > o· I). McCance & Widdowson (1959) recorded a 47 per cent increase in plasma volume from birth to 24 hours, and Ramirez et at. (1963) a 31 per cent increase. It is apparent from the plasma volume values presented in Tables II and III, and from the observations of Ramirez et at. (1963), that most of the increase in volume occurs within the first 12 hours after birth. Mean values recorded at 10 days for plasma and blood volumes expressed in ml/kg bodyweight (Table II) or as ml/litre body water (Table III) were higher than mean values obtained at birth or 30 days with at least a 5 per cent level of significance. A fall in plasma sodium, potassium and inorganic phosphate concentrations and osmolality was observed in piglets from birth to 6- 12 hours (Pownall, 1970). From birth to 12 hours there is also a significant (P < 0'05 ) fall in haematocrit (Table II). A similar fall in the concentration of plasma electrolytes and formed elements was recorded by McEwan, Fisher & Selman (1968) in calves fed either milk or colostrum from birth. These findings suggest that in both piglets and calves, plasma volume expansion is the r esult of dilution of the initial plasma volume by hypotonic fluid. In view of findings on the changes in the relative proportions of the body fluids of piglets within 24 hours of birth, iLseems probably that the fluid taken up from colostrum is distributed unevenly between the various body fluid compartments (Pownall, 197 2 ) . The results presented in Table I show that with increasing age, body water expressed in terms of ml/kg decreased. This presumably reflects the effect of body fat deposition on the expression of body fluid volumes per unit of bodyweight as outlined in the introduction. The effect on the changes with age in plasma volume when expressed relative to bodyweight and body water are of
BLOOD AND PLASMA VOLUMES OF NEONATAL PIGS
587
interest. Thus, taking from Table II, the average plasma volume on days 1-3 oflife as 72 ml/kg bodyweight and on the 20- 30th days as 60 ml/kg bodyweight, 72 - 60 this represents a decrease in volume equivalent to - - - X 100 = 16'7 per cent.
72
Alternatively, taking from Table III the average plasma volume on days 1- 3 of life as go ml/litre body water and as 83 ml/litre body water on the 20- 30th 9 0 -:83 days, this represents a decrease of only -. - - X 100 = 7.8 per cent.
90
In conclusion, it appears advisable if assessing changes in the plasma and blood volumes of piglets whose adiposity may vary in relation to age, growth rate and disease, to ad~pt body water as the basis of reference.
ACKNOWLEDGEMENTS
This study was supported by the Meat and Livestock Commission and the Agricultural Research Council. The authors gratefully acknowledge the technical assistance of Mrs Eileen McKerracher and Mrs Anne Claridge and the advice of Professor R. J. Fitzpatrick and Dr E. C. Pickering.
RE.F.E.REN.CES- . . . ... _ ._
ALLEN, T. H. (1953). Am. J. Physiol. 175,227· ANDERSON, D. M. (1970) . J. compo Path. 80,1 63 . DALTON, R. G. & FISHER, E. W. (1961). Br. vet. J. 117, 115. KUNESH, J. P. (1966) . M.Sc. Thesis. Ames: Iowa State University. MANNERS, M.J. & MCCREA, M. R. (1963). Br. J. Nutr. 17,495. MCCANCE, R . A. & WIDDOWSON, E. M. (1959) . J. Physiol. , Lond. 145,547. McEwAN, A . D. , FISHER, E. W . & SELMAN, I. E. (1968). R es. vet. Sci. 9,284. POWNALL, R. (1970). Br. vet. J. 126, 465. POWNALL, R. ( 1972) . Ph.D. Thesis, University of Liverpool. POWNALL, R. & DALTON, R. G. (1969). Proc. 1St into Congr. Pig vet. Soc., Cambridge. RAMIREZ, C. G., MILLER, E. R ., ULLREY, D. E. & HOEFFER, J . A. (1963). J. Anim. Sci. 22, 1068. TALBOT, R. B. & SWENSON, M. J. (1963) . Am. J. vet. Res. 24,467. WOOD, A.J. & GROVES, T. D. D. (1965). Can. J. An. Sci. 45, 8. (Accepted for -publication 15 February 1973)
Vobunes sanguin et plasmatique de pores nouveaux-nes expriInes par rapport au poids corporel et a l'eautotaleorporelle (Pownall et Dalton) ResUIl1e. On determina chez des porcelets a la naissance et par la suite a intervalles jusqu'a l'age de 30 jours, Ie volume plasmatique et sanguin, l'hematocrite veineux et Ie volume d'eau total~ corporelle. Des variations significatives de ces parametres furent observes avec l'age. On fit une analyse des avantages a exprimer les volumes liquidiens corporels par rapport au poids . corpore! e~ a l'eau totale corporelle.
S88
BRITISH VETERINARY JOURNAL, 129,6
Blu~
und Plasmavolwnen bel neugeborenen Ferkeln in Beziehung zwn Korpergewicht und GeslUlltwassergehalt des Korpers (Pownall und Dalton) Zusauunenfassung. Unmittelbar nach dem Wurf und in Intervallen danach wurden 30 Tage lang bei Ferkeln Plasmaund Blutvolumen, venose Haematokritwerke und der Gesamtwassergehalt des Korpers festgestellt. Signifikante Anderungen wurden entsprechen dem Alter in diesen Parametern beobachtet. Die Vorzuge der Beschreibung des Korperflussigkeitsvolumens in Beziehung zum Gewicht oder Gesamtwassergehalt des Korpers wurden analysiert. VolUmenes de la sangre y plasma de cerdos neonatales expresados en relaci6n a peso corporal y al agua total del cuerpo (Pownall y Dalton) Reswnen. Se determinaron el volumen de sangre y plasma, hemat6crito venoso yel contenido total de agua corporal de lechones en el momenta de nacer y despues a various intervalos hasta los 30 dias. Se observaron cambios en estos parametros a medida que los lechonea avanzaron en edad. Se efectu6 u analisis de los meritos de expresar los volumenes corporales de flUido en relaci6n al peso corporal 0 agua total del cuerpo.
THE GEORGE FLEMING PRIZE This annual prize for the best article published in the journal will be awarded this year to W. A. Watson, S. Terlecki, D. S. P. Patterson, D. Sweasey, C. Nancy Herbert and]. T. Done for their paper on "Experimentally Produced Progressive Retinal Degeneration (Bright Blindness) in Sheep", which appeared in the September 1972 issue of the journal. The prize was instituted in 1965 to signalize the ninetieth year of publication of the British Veterinary Journal, and to honour its founder, Professor George Fleming.