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Weight gain pattern in piglets during the first 24 h after farrowing
Livestock Production Science, 28 ( 1991 ) 321-330
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Elsevier Science Publishers B.V., Amsterdam
Weight gain pattern in piglets during the first 24 h after farrowing H. Castr6na, B. Algers b, and H. Saloniemi a "('ollege ~[Veterinao' Medicine, Department of Animal ltvgienc, P.O.B. 6, SF-00581 Helsinki, Finland ~'Swedish University q(Agricultural Sciences, Department Rf A nimal ttvgiene, P. O. B. 345, S-53224 Skara, Sweden (Accepted 21 November 1990)
ABSTRACT Castr6n, H., Algers, B. and Saloniemi, H., 1991. Weight gain pattern in piglets during the first 24 h after farrowing. Livest. Prod. Sci., 28: 321-330. Weight gain pattern in newborn piglets was investigated to gain a better understanding of how milk is consumed during and 24 h after farrowing. The first (A) and the sixth (B) piglet of 10 sows were weighed at 5-min intervals during the first 5 h and before and after the first observed suckling at 4-h intervals (the later periods) after the birth of the first piglet. On average, all piglets gained weight ( 12 g) in bouts with shorter intervals ( 14 rain ) during the first 2 h of litter age than during the following 3 h (20 min ). On average, the weight gain during both the first and the second hour of piglet age was 45 g and during tile following 3 h 25 g. Approximately 50% of the sucklings were successful during the later periods and the average weight gain per piglet was about 20 g per suckling. The interval between sucklings was on average 35 min. Piglets that were heavier at birth ( > 1500 g) gained significantly more weight than the lighter piglets ( < 1300 g) during the first 24 h. Newborn piglets seem to gain weight in bouts. This gain is larger during the first 2 h of piglet age than during the following hours. Keywords: piglet, newborn: weight gain: suckling intervals.
INTRODUCTION
The mortality of live-born piglets is 15-20% before weaning (e.g., Fahmy and Bernard, 1971; Curtis, 1974; English and Smith, 1975; Nielsen et al., 1976; Simensen and Karlberg, 1980). Most dying piglets succumb during the first days of life because of starvation caused by insufficient milk production of the sow (De Passill6 and Rushen, 1989) and/or competition in litters showing large variation in litter weight (Fahmy and Bernard, 1971; English and Smith, 1975; Hartsock and Graves, 1976; English and Morrison, 1984; Dyck and Swierstra, 1987). These affect the possibility of the piglet to regularly 0301-6226/91/$03.50
© 1991 - - Elsevier Science Publishers B.V.
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consume adequate amounts of milk during the first days which leads to hypothermia and weakness, and piglets are easily crushed by the sow (Fahmy and Bernard, 1971; Curtis, 1974; English and Smith, 1975; Hartsock and Graves, 1976; English and Morrison, 1984). As the piglets are active at the udder nearly constantly during the first hours of life and milk can be easily pressed from the teats, it is assumed that milk is continuously available during this time (Hemsworth et al., 1976; Lewis and Hurnik, 1985 ). However, studies of the milk yield and ejection from the different teats of a sow by both hand- (Fraser, 1984; Fraser and Lin, 1984) and machine-milking (Fraser et al., 1985) have shown that milk is ejected intermittently already during the first hours after the birth of the first piglet. Continuous hand-milking showed that milk was released in discrete ejections after initial high yield and that these ejections varied in duration, yield and intervals compared with ejections during later lactation (Fraser, 1984 ). This leads to the assumption that milk is also consumed intermittently and that it is important for piglets to be able to suck regularly immediately after birth. According to De Passill6 and Rushen (1989) limited colostrum availability and consumption as early as during farrowing cause high mortality and poor growth rate of piglets. Litters with low weight gain during the first days of life continue to have low gains later in life (Thompson and Fraser, 1988 ). The weight gain rate of newborn piglets has not been measured regularly during their first hours of life. The behaviour of the animals alone does not clearly show when an individual piglet consumes milk during this time, as it does 8-10 h later when synchronous suckling has developed (Lewis and Hurnik, 1985; Castr6n et al., 1989b). The objective of this study was to describe the milk consumption of piglets through their weight gain pattern during the first 24 h of life. The suckling success and the suckling intervals were also studied during this period.
MATERIALS AND METHODS
This study was carried out at a private pig breeding farm in Finland. The farrowing sows were kept in three separate farrowing units with 12 sows and their litters for up to 5-6 weeks of age in each. The sows could move freely in 2.2 × 2.2-m pens with concrete floors. The sows were fed with a blend of barley and concentrate twice a day between 6 and 9 a.m. and between 3 and 4 p.m. They had free access to water. A heat lamp was set up in the piglet creep 5 h after the farrowing had started; 1-2 kg straw was provided to each pen daily. The temperature in the farrowing units was 17-20 ° C. The first (A) and the sixth (B) piglet of four Yorkshire and six YorkshireFinnish Landrace multiparous sows were weighed at 5-min intervals during the first 5 h (the 5-h period) after the birth of the first piglet and then before
WEIGHT GAIN PATTERN IN PIGLETS
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and after the first suckling observed at 8, 12, 16, 20 and 24 h (the later periods). There were on average 12 piglets per litter (range from 4 to 15 ); 10 A and 10 B piglets were studied. In three cases out of 10, 1-6 piglets were sucking the teats when observations started (30-60 min after the birth of the first piglet) and their birth weights are missing. Otherwise there was no suckling before the start, i.e., 225 min after the birth of the first piglet. The A and B piglets were marked at birth and weighed at 5-min intervals. An automatic weighing device (Sartorius 1501MP8 scales and 7279 weight data printer), sampling automatically 25 weight recordings within 2 s was used. The mean weight was then calculated at an accuracy of 1 g. The defects arising from urination and defecation were not eliminated. If the B piglet was dead at birth, the seventh was weighed instead. When six piglets were sucking before the start of observations, two piglets were marked randomly as A and B piglet. That litter was not included in the first-hour observations. In a litter of four piglets about 4 h passed between the birth of the first and the second piglet, and the second piglet was therefore weighed after the A piglet. All piglets weighed after the A piglet are here referred to as B piglets. The data were analysed partly in relation to piglet age and partly in relation to litter age, i.e., from the first hour after the birth of the first piglet. There were 51-59 weighings per A piglet and 14-55 per B piglet during the 5-h period. The A piglets were recorded during the whole 5-h observation period and the B piglets for an average of 3.5 h. Four piglets were weighed only during their first 2 h, i.e., the 4th and the 5th observation hours. One A piglet was crushed by the sow in the 20-24-h period. A weight gain of more than 5 g during a 5-min period was considered as a successful suckling and used separately in the calculations as a G period. A gain of 0-5 g was considered as a neutral (N) period and a loss as an L period. The weight change for all piglets and separately for piglets actually gaining weight was counted per hour of piglet and litter age during the 5-h period and per hour of litter age after that. The percentage of piglets gaining weight was calculated. The total weight gain at the end of the 5-h period was calculated. During each later period, two consecutive sucklings were observed. The two piglets were weighed before and after the first observed suckling. The start of a suckling was determined by piglet activity at the udder and by the rhythmical grunting of the sow. A suckling was considered ended when most of the piglets fell asleep and the sow was quiet. A milk ejection was recognized by an increasing grunting rhythm of the sow and rapid mouth movements of the piglets (Whittemore and Fraser, 1974). These sucklings were registered as successful (SS). The starting time and success of the second suckling were registered; 91 out of 98 observed sucklings could be defined as successful or unsuccessful (US). The percentages of successful and unsuccessful sucklings were counted for each sow and each later period. Forty-seven suckling intervals were observed. One sow had an interval ex-
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n . CASTRIeN ET AL.
ceeding 240 min between the 8th and the 12th hour (not used in calculations), and one suckling interval is missing from the last period of one sow. The suckling intervals were divided into four categories: SS-SS, SS-US, U S US and US-SS, and counted from the start of the previous suckling to the beginning of the next one. The average weight gain of the A and B piglets was counted for the later periods in connection with SS. The total weight gain at the end of the 24 h was calculated. In the statistical testing of weights we used the two-tailed paired t-test for pair differences. All variations are given as 1 s.d. RESULTS
The 5-h period (1-5 h afterfarrowing) Weight gain intervals'. The percentages of G, N and L periods during the 5-h period and the average weight gain per piglet are presented in Table 1. There were no significant differences between the A and B piglets. The intervals between the G periods during the first 2 h of litter age after the birth of the first piglet were significantly shorter per piglet ( 14_+ 9 min, n = 32) than the intervals during the following 3 h (20_+ 19 min, n = 92, P<0.01).
Weight gain. Not all piglets gained weight during the observation hours. During the 2nd hour of piglet age the average weight gain for all piglets was 32 +_30 g, which was significantly more than during the 1st hour (9 + 37 g) and the 3rd-5th hours ( 14 + 26 g, 9 _+29 g and 17 _+22 g, respectively, P < 0.05 ) (Fig. 1 ). There were no significant differences in gain between the 3rd, 4th and 5th hours. On the other hand, the average weight gain for those piglets that did gain weight during the 1st (44%) and the 2nd (75%) hour was on average 44.5 +_0.7 g. This was significantly more than the weight gain during the folTABLE 1 The percentages of G (gain), N ( neutral ) and L ( loss ) periods, their variation and the average weight gain per piglet during the 5-h period % Of periods
G N k
Variation (%)
X
S
19 33 46
Il 13 19
Weight gain (g) S
.V
5-33 16-49 12-80
12.0 1.7 -2.8
4.6 0.4 1.3
325
W E I G H T GAIN PATTERN IN PIGLETS
70
W~ o
~ 4o [
3o
C
20
..............
:
h io
fl
n o g e -io -20 -30 2
4
Hours Fig. 1. The average weight change (g) and standard deviation per piglet and per hour of piglet age for all piglets (A) and for piglets that actually gained weight (B) during the first 5 h after the birth of the first piglet. TABLE 2 The average weight gain (g) and standard deviation per piglet and per hour of litter age for all piglets and for piglets that actually gained weight during the first 24 h after the birth of the first piglet Litter age (h) Weight gain of all piglets
x s
% of piglets gaining weight Their weight gain
x s
1
2
3
4
5
8
12
16
20
24
10 39
29 31
15 26
11 29
20 26
11 30
4 32
3 25
8 31
-6 33
46
69
69
60
65
65
60
55
55
37
45 37
45 23
29 18
27 25
33 23
26 26
25 16
21 16
32 15
23 26
lowing 3 h (28+ 18 g, 25_+28 g and 28_+ 18 g, respectively, P < 0 . 0 5 ) (Fig. 1 ). When counted by the hour of litter age, this weight gain pattern per hour and per piglet was similar for those piglets that gained weight (on average 62 _+ 10% ) and for all piglets (Table 2 ). Sixteen of the 20 piglets increased on average 98.9 + 67.5 g in weight during the 5-h period. Two A and two B piglets lost an average of 40.3_+ 4.2 g in weight from birth until the end of the 5-h period. One pair belonged to a sow which started to suckle 3 h after the birth of the first piglet. The other B piglet did not suck during this time and the other A piglet had only a couple of G periods. The total weight gain during the G and N periods during the first 5 h tended
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H. CASTREN ET a.L.
to be greater in the A piglets than in the B piglets ( 148 _+74 g and 108 _+79 g, respectively, n.s. ). However, the A piglets lost significantly more weight during the L periods than did the B piglets (66 _+28 g and 42 _+ 19 g, respectively, P < 0.05). The A piglets lost on average 45% and the B piglets 39% of their total weight gain. There were no differences in birth weight between the A and B piglets. Those A and B piglets that were heavier at birth ( > 1500 g, n = 8) tended to gain more weight ( 113.8 _+94.2 g) during the first 5 h than the middle-weight piglets ( 1300-1500 g, n = 6 ), which gained more ( 57.3 _+56.5 g) than the small piglets ( < 1300 g, n = 6, 46.3 _+66.0 g). There were no significant differences between these weight gains.
The later periods (8-24 h after farrowing) Suckling success. O f the sucklings observed, 53 _+ 17% were unsuccessful. The a m o u n t of US varied from 12 to 73% between the sows. The percentage of US was 50%, 44%, 60%, 52% and 61% for the later periods, respectively. The average weight gain per piglet during the observed SS was 19.7 + 9.4 g. There were no significant differences between' the sows, the later periods, or the A and B piglets.
Suckling intervals. The interval length between all types of sucklings varied from 8 to 105 min. The mean suckling interval for all sows was 35 _+22 min. There were no significant differences between the later periods ( 32 _+23 min, 34_+21 min, 40_+25 min, 31 + 12 min and 39_+27 min, respectively). However, there were significant differences between some sows in their mean interval lengths during the later periods. The interval length was on average 38_+23 min (range 12-91 m i n ) between SS-SS and on average 21 + 11 min (range 8-44 m i n ) between U S - U S . The mean suckling interval length after a SS was 35 _+21 min and after an US 23 +_24 rain. There were no significant differences between the SS-SS, SS-US U S - U S and US-SS intervals, although a preceding US tended to shorten the interval to the next suckling.
Weight gain. During the 8th-24th hours of litter age all piglets gained weighl on average 6.4_+ 3.2 g per period with no significant differences between the periods (Table 2 ). The percentage of piglets that actually gained weight during these hours declined from 65% at the 8th hour to 37% at the 24th h. These piglets gained an average of 25.4 _+4.2 g per period and per piglet, which was nearly as much as the gain during the first 3-5 h (Table 2). At the end of the first 24 h after the birth of the first piglet, 17 piglets out of 20 gained an average of 124.0_+ 89.0 g (range 4-277 g). There were no significant differences between the A and B piglets. Three piglets had a lower weight at this time than at birth (on average 48.7 __89.0 g).
WEIGHT GAIN PATTERN IN PIGLETS
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The A and B piglets with a birth weight over 1500 g gained significantly more weight ( 138.5 +_ 103.1 g) during their first 24 h than the smallest piglets with weights < 1300 g (34.1 _+54.7 g, P < 0.05 ). The piglets with a birth weight of 1300-1500 g gained 126.7 + 100.3 g. DISCUSSION
Even though we did not weigh the whole litters, the weight gain of the A and B piglets indicate that birth time, weight or order did not affect the weight gain during the 5-h period, in agreement with Hemsworth et al. (1976). Heavier piglets gained significantly more weight during the first 24 h than the smaller piglets. Hartsock and Graves (1976) have reported that the first piglets are heavier at birth and may thus suckle more frequently and grow better than lighter piglets born later. The intervals between the G periods were significantly shorter during the first 2 h of litter age compared with the following 3 h. Moreover, the largest amount of milk was consumed during the first and the second hour of both piglet and litter age. Most piglets gained weight during the second hour of piglet age. Our results suggest that piglets gain weight with certain intervals, in bouts, during the first 5 h after the birth of the first piglet. This confirms the results of Fraser (1984), who reported that about 2 h after the birth of the first piglet the milk ejections (2-20 g / m i n ) during hand-milking appeared at intervals of 5-30 min. These ejections lasted 1-4 min and were sometimes associated with birth of a piglet, body movements of the sow or other events such as squealing of piglets, or nursing of other litters. In farrowing sows only single teat stimulation seems to be sufficient for milk ejection. Possibly this is due to a low threshold for oxytocin release which is spurt-like (Fraser, 1984) just as later in lactation, when sucklings appear at more regular intervals (Ellendorffet al., 1982 ). Our results imply that milk is ejected in longer spurts with higher yield and triggered more easily and frequently than later during sucklings. The piglet weight loss per 5-min period was usually a few grams. These losses can arise from respiration, loss of saliva, mucus and other body debris. However, greater losses in weight arise from urination and defecation and also from errors involved in the weighing process (Barber et al., 1955 ). These defects were not corrected in our study. We did not have the heat lamp on during the first observation hours, which might have affected weight gain as the temperature ranged from 17 to 20°C. However, the lamp was kept on after the first 5 h. In addition, straw was placed in the pens. The piglets had constant free access to the sow's udder. The weight gain per G period in our study was similar to that found by Le Dividich and Noblet ( 1981 ) for piglets in cold conditions several hours after farrowing while during the later periods
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H. CASTRI~N ET AL.
the gain in our study was greater per suckling than reported for piglets in warm conditions (Le Dividich and Noblet, 1981). Half of the weight gained was lost during the 5-h period in our study. The significantly greater loss in the A piglets might be due to the longer observation period in that group and consequently to the larger number of L periods compared with the B piglets. Full stomach increases the length of resting and suppresses the milk consumption of the piglets (Stephens, 1975). This m a y explain why A piglets were often asleep for a couple of hours after the initial active period of their life while the B piglets were still active at the udder. About 50% of the later sucklings were unsuccessful. Most sucklings, whether SS or US, had a nearly equally long interval, suggesting that there are in all sucklings some satisfying elements for both the sow and the piglets. A relatively high number of US were observed also in semi-natural conditions during the first 3 days after farrowing (Newberry and Wood-Gush, 1985; Castr6n et al., 1989a). The suckling intervals were of about the same length as in the present study (Castr6n et al., 1989a), suggesting that the suckling success of the indoor sows kept in conventional pens is not much affected by the suckling behaviour of other litters or indoor conditions. The function of US during the first days of lactation might be to increase milk production, as several lactogenic and gastrointestinal hormones have been shown to be released in response to teat stimulation by piglets (Uvn~is-Moberg et al., 1984; Algers et al., 1989). Uvn~is-Moberg and Winberg (1989) reported that non-nutritive sucking may also increase hormone release in children and improve their growth and development. Perhaps this is true also for piglets. The percentage of piglets that gained weight in our study during the later periods declined towards the end of the 24 h. The average weight gain in these piglets was nearly the same as during the first 3-5 h, in agreement with Hemsworth et al. (1976). CONCLUSIONS Piglets gained weight in bouts during the first 5 h of their life and at shorter intervals during the first 2 h than during the following hours. There were many piglets that did not increase in weight every hour, but those who did, gained about 45 g during both the first and the second hour of piglet age and about 25 g during the following 3 h. During the 8- to 24-h periods after farrowing the weight gain per piglet was about 25 g per period. During this time about 50% of the sucklings were unsuccessful. Similar results in a semi-natural environment suggest that environmental factors do not affect suckling success in indoor sows kept in conventional pens. ACKNOWLEDGEMENTS We wish to thank Mr. Fredrik Schulman for allowing us to use his farm in
WEIGHT GAIN PATTERN IN PIGLETS
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our research. The study was supported by a grant from the Finnish Veterinary Association. REFERENCES Algers, B., Madej, A., Rojanasthien, S. and Uvn~is-Moberg, K., 1989. Quantitative relationships between suckling-induced teat stimulation and the release of prolactin, gastrin, somatostatin, insulin, glucagon and VIP in sows. In: B. Algers (Thesis), Vocal and Tactile Communication During Suckling in Pigs. Aspects on Functions and Effects of Continuous Noise. Rapport 25, Skara, pp. 97-121, Barber, R.S., Braude, R. and Mitchell, K.G., 1955. Studies on milk production of Large White pigs. J. Agric. Sci., Camb., 46:97-118. Castrdn, H., Algers, B. and Jensen, P., 1989a. Occurrence of unsuccessful sucklings in newborn piglets in a semi-natural environment. Appl. Anita. Behav. Sci., 23: 61-73. Castrdn, H., Algers, B., Jensen, P. and Saloniemi, H., 1989b. Suckling behaviour and milk consumption as a response to sow grunting in newborn piglets. Appl. Anim. Behav. Sci., 24: 227-238. Curtis, S.E., 1974. Responses of the piglet to perinatal stressors. J. Anita. Sci., 38:1031-1036. De Passill6, A.-M. and Rushen, J., 1989. Using early suckling behavior and weight gain to identify piglets at risk. Can. J. Anim. Sci., 69: 535-544. Dyck, G.W. and Swierstra, E.E., 1987. Causes of piglet death from birth to weaning. Can. J. Anim. Sci., 67: 543-547. Ellendorff, F., Forsling, M.L. and Poulain, D.A., 1982. The milk ejection reflex in the pig. J. Physiol., 333: 577-594. English, P.R. and Morrison, V., 1984. Causes and prevention of piglet mortality. Pig News Inform., 5: 369-376. English, P.R. and Smith, W.J., 1975. Some causes of death in neonatal piglets. Vet. Annu., 15: 95-104. Fahmy, M.H. and Bernard, C., 1971. Causes of mortality in Yorkshire pigs from birth to 20 weeks of age. Can. J. Anim. Sci., 51: 351-359. Fraser, D., 1984. Some factors influencing the availability ofcolostrum to piglets. Anim. Prod., 39:115-123. Fraser, D. and Lin, C.S., 1984. An attempt to estimate teat quality of sows by hand milking during farrowing. Can. J. Anim. Sci., 64:165-170. Frascr, D., Nicholls, C. and Fagan, W., 1985. A sow milking machine designed to compare to yield of different teats. J. Agric. Eng. Res., 31:371-376. Hartsock, T.G. and Graves, H.B., 1976. Neonatal behaviour and nutrition-related mortality in domestic swine. J. Anim. Sci., 42: 235-241. Hemsworth, P.H., Winfield, C.G. and Mullaney, P.D., 1976. Within-litter variation in the performance of piglets to three weeks of age. Anim. Prod., 22:351-357. Le Dividich, J. and Noblet, J., 1981. Colostrum intake and thermoregulation in the neonatal pig in relation to environmental temperature. Biol. Neonat., 40:167-174. Lewis, N.J. and Hurnik, J.F., 1985. The development of nursing behaviour in swine. Appl. Anim. Behav. Sci., 14: 225-232. Newberry, R.C. and Wood-Gush, D., 1985. The suckling behaviour of domestic pigs in a seminatural environment. Behaviour, 95:11-25. Nielsen, N.C., Bille, N., Svendsen, J. and Riising, H.-J., 1976. Sygdomsbekaempelse i svinebesaetninger. Inst. Int. Med., Den Kgl. Veterinaer- og Landhojskole, Kobenhavn. Simensen, E. and Karlberg, K., 1980. A survey of preweaning mortality in pigs. Nord. Veterinaermed., 32:194-200. Stephens, D.B., 1975. Effects of gastric loading on the sucking response and voluntary milk intake in neonatal piglets. J. Comp. Physiol. Psychol., 88: 796-805.
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Thompson, B. and Fraser, D., 1988. Variation in piglet weights: weight gains in the first days after birth and their relationship with later performance. Can. J. Anita. Sci., 68:581-590. Uvniis-Moberg, K. and Winberg, J., 1989. Role for sensory stimulation in energy economy of mother and infant with particular regard to the gastrointestinal endocrine system. In: E. Lebenthal (Editor), Textbook of Gastroenterology and Nutrition in Infancy. Raven Press, Ltd., New York, NY, 53. Uvn~is-Moberg, K., Eriksson, M., Blomquist, L.-E., Kunavongkrit, A. and Einarsson, S., 1984. Influence of suckling and feeding on insulin, gastrin, somatostatin and VIP levels in peripheral venous blood of lactating sows. Acta Physiol. Scand., 121 : 31-38. Whittemore, C.T. and Fraser, D., 1974. The nursing and suckling behaviour of pigs. It. Vocalization of the sow in relation to suckling behaviour and milk ejection. Br. Vet. J., 130: 346356. RESUME Castr6n, H., Algers, B. et Saloniemi, H., 1991. Evolution du gain de poids des porcelets au cours des premieres 24 heures aprbs la naissance. Livest. Prod. Sci., 28:321-330 (en anglais). Les variations du gain de poids des porcelets ont 6t6 6tudi6es afin de mieux comprendre l'dvolution de la consommation de lair au cours des premibres 24 h apr6s la naissance. Le l er (A) ct le 6me (B) porcelcts de 10 truies 6talent pcses routes les 5 rain pendant les cinq premi6rcs heures, puis avant et apr6s la premi6re t6t6e observ6e au cours d'intervalles de quatre heures dc temps (les derni6res p6riodes) apr6s la naissance du premicr porcelet. En moyenne, tous les porcelets gagnaient 12 g de poids par h-coups separ6s par des intervalles plus courts ( 14 min ) duranl les deux premibres heures d'fige que pendant les trois heures suivantes (20 rain). En moyenne, le gain 6tait de 45 g pendant la premi6re et la deuxibme heures de vie, et de 25 g pendant ies 3 suivantes. Environ 50% des t6t6es 6taient r6ussies pendant les dernibres p6riodes et le gain de poids moyen du porcelet 6tait de 20 g par t6tee. L'intervalle moyen entre t6tces 6fair de 35 min. Les porcelets les plus lourds h la naissance ( > 1500 g) gagnaient significativement plus de poids que les plus 16gers ( < 1300 g) au cours des 24 premi6res heures. Les porcelets nouvcaux-n6s semblent gagner du poids par a-coups. Ce gain est plus important pendant les deux premibres heures que par la suite. KU RZFASSUNG Castr6n, H., Algers, B. und Saloniemi, H., 1991. Die Gewichtsentwicklung der Ferkel w~ihrend der ersten 24 Stunden nach dem Ferkeln. Livest. Prod. Sci., 28:321-330 (aufenglisch). Die Gewichtsentwicklung neugeborener Ferkel wurde untersucht, um besser zu verstehen, wieviel Milch w~ihrend und 24 Stunden nach dem Ferkeln verbraucht wird. Das erste (A) und das sechste ( B ) Ferkel von zehn Sauen wurde in 5-Minuten-lntervallenw~ihrend der ersten fiinf Stunden sowie vor und nach dem ersten Saugen in 4-Stunden-lntervallen (die sp~iteren Perioden ) nach der Geburt des ersten Ferkels gewogen. Im Mittel wuchsen alle Ferkel 12 g in Runden mit kiirzeren Intervallen (14 Minuten) w~ihrend der ersten beiden Lebensstunden als in den folgenden 3 Stunden (20 Minuten). im Mittel war der Zuwachs fiber die ersten beiden Lebensstunden 45 g und fiber die folgenden drei Stunden 25 g. Etwa 50% der Saugeversuche war ergfolgreich w~ihrend der sp~iteren Perioden, und der mittlere Gewichtszuwachs je Saugakt war 20 g. Das Sauge-lntervall betrug 35 Minuten. Bei der Geburt schwerere Ferkel ( > 1500 g) hatten einen signifikant h6heren Gewichtszuwachs in den ersten 24 Studen als leichter geborene Ferkel ( < 1300 g). Neugeborene Ferkel scheinen in Schfiben zuzunehmen. Der Zuwachs ist w~ihrend der ersten zwei Stunden gr6Ber als in den folgenden Stunden.
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Elsevier Science Publishers B.V., Amsterdam
Weight gain pattern in piglets during the first 24 h after farrowing H. Castr6na, B. Algers b, and H. Saloniemi a "('ollege ~[Veterinao' Medicine, Department of Animal ltvgienc, P.O.B. 6, SF-00581 Helsinki, Finland ~'Swedish University q(Agricultural Sciences, Department Rf A nimal ttvgiene, P. O. B. 345, S-53224 Skara, Sweden (Accepted 21 November 1990)
ABSTRACT Castr6n, H., Algers, B. and Saloniemi, H., 1991. Weight gain pattern in piglets during the first 24 h after farrowing. Livest. Prod. Sci., 28: 321-330. Weight gain pattern in newborn piglets was investigated to gain a better understanding of how milk is consumed during and 24 h after farrowing. The first (A) and the sixth (B) piglet of 10 sows were weighed at 5-min intervals during the first 5 h and before and after the first observed suckling at 4-h intervals (the later periods) after the birth of the first piglet. On average, all piglets gained weight ( 12 g) in bouts with shorter intervals ( 14 rain ) during the first 2 h of litter age than during the following 3 h (20 min ). On average, the weight gain during both the first and the second hour of piglet age was 45 g and during tile following 3 h 25 g. Approximately 50% of the sucklings were successful during the later periods and the average weight gain per piglet was about 20 g per suckling. The interval between sucklings was on average 35 min. Piglets that were heavier at birth ( > 1500 g) gained significantly more weight than the lighter piglets ( < 1300 g) during the first 24 h. Newborn piglets seem to gain weight in bouts. This gain is larger during the first 2 h of piglet age than during the following hours. Keywords: piglet, newborn: weight gain: suckling intervals.
INTRODUCTION
The mortality of live-born piglets is 15-20% before weaning (e.g., Fahmy and Bernard, 1971; Curtis, 1974; English and Smith, 1975; Nielsen et al., 1976; Simensen and Karlberg, 1980). Most dying piglets succumb during the first days of life because of starvation caused by insufficient milk production of the sow (De Passill6 and Rushen, 1989) and/or competition in litters showing large variation in litter weight (Fahmy and Bernard, 1971; English and Smith, 1975; Hartsock and Graves, 1976; English and Morrison, 1984; Dyck and Swierstra, 1987). These affect the possibility of the piglet to regularly 0301-6226/91/$03.50
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consume adequate amounts of milk during the first days which leads to hypothermia and weakness, and piglets are easily crushed by the sow (Fahmy and Bernard, 1971; Curtis, 1974; English and Smith, 1975; Hartsock and Graves, 1976; English and Morrison, 1984). As the piglets are active at the udder nearly constantly during the first hours of life and milk can be easily pressed from the teats, it is assumed that milk is continuously available during this time (Hemsworth et al., 1976; Lewis and Hurnik, 1985 ). However, studies of the milk yield and ejection from the different teats of a sow by both hand- (Fraser, 1984; Fraser and Lin, 1984) and machine-milking (Fraser et al., 1985) have shown that milk is ejected intermittently already during the first hours after the birth of the first piglet. Continuous hand-milking showed that milk was released in discrete ejections after initial high yield and that these ejections varied in duration, yield and intervals compared with ejections during later lactation (Fraser, 1984 ). This leads to the assumption that milk is also consumed intermittently and that it is important for piglets to be able to suck regularly immediately after birth. According to De Passill6 and Rushen (1989) limited colostrum availability and consumption as early as during farrowing cause high mortality and poor growth rate of piglets. Litters with low weight gain during the first days of life continue to have low gains later in life (Thompson and Fraser, 1988 ). The weight gain rate of newborn piglets has not been measured regularly during their first hours of life. The behaviour of the animals alone does not clearly show when an individual piglet consumes milk during this time, as it does 8-10 h later when synchronous suckling has developed (Lewis and Hurnik, 1985; Castr6n et al., 1989b). The objective of this study was to describe the milk consumption of piglets through their weight gain pattern during the first 24 h of life. The suckling success and the suckling intervals were also studied during this period.
MATERIALS AND METHODS
This study was carried out at a private pig breeding farm in Finland. The farrowing sows were kept in three separate farrowing units with 12 sows and their litters for up to 5-6 weeks of age in each. The sows could move freely in 2.2 × 2.2-m pens with concrete floors. The sows were fed with a blend of barley and concentrate twice a day between 6 and 9 a.m. and between 3 and 4 p.m. They had free access to water. A heat lamp was set up in the piglet creep 5 h after the farrowing had started; 1-2 kg straw was provided to each pen daily. The temperature in the farrowing units was 17-20 ° C. The first (A) and the sixth (B) piglet of four Yorkshire and six YorkshireFinnish Landrace multiparous sows were weighed at 5-min intervals during the first 5 h (the 5-h period) after the birth of the first piglet and then before
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and after the first suckling observed at 8, 12, 16, 20 and 24 h (the later periods). There were on average 12 piglets per litter (range from 4 to 15 ); 10 A and 10 B piglets were studied. In three cases out of 10, 1-6 piglets were sucking the teats when observations started (30-60 min after the birth of the first piglet) and their birth weights are missing. Otherwise there was no suckling before the start, i.e., 225 min after the birth of the first piglet. The A and B piglets were marked at birth and weighed at 5-min intervals. An automatic weighing device (Sartorius 1501MP8 scales and 7279 weight data printer), sampling automatically 25 weight recordings within 2 s was used. The mean weight was then calculated at an accuracy of 1 g. The defects arising from urination and defecation were not eliminated. If the B piglet was dead at birth, the seventh was weighed instead. When six piglets were sucking before the start of observations, two piglets were marked randomly as A and B piglet. That litter was not included in the first-hour observations. In a litter of four piglets about 4 h passed between the birth of the first and the second piglet, and the second piglet was therefore weighed after the A piglet. All piglets weighed after the A piglet are here referred to as B piglets. The data were analysed partly in relation to piglet age and partly in relation to litter age, i.e., from the first hour after the birth of the first piglet. There were 51-59 weighings per A piglet and 14-55 per B piglet during the 5-h period. The A piglets were recorded during the whole 5-h observation period and the B piglets for an average of 3.5 h. Four piglets were weighed only during their first 2 h, i.e., the 4th and the 5th observation hours. One A piglet was crushed by the sow in the 20-24-h period. A weight gain of more than 5 g during a 5-min period was considered as a successful suckling and used separately in the calculations as a G period. A gain of 0-5 g was considered as a neutral (N) period and a loss as an L period. The weight change for all piglets and separately for piglets actually gaining weight was counted per hour of piglet and litter age during the 5-h period and per hour of litter age after that. The percentage of piglets gaining weight was calculated. The total weight gain at the end of the 5-h period was calculated. During each later period, two consecutive sucklings were observed. The two piglets were weighed before and after the first observed suckling. The start of a suckling was determined by piglet activity at the udder and by the rhythmical grunting of the sow. A suckling was considered ended when most of the piglets fell asleep and the sow was quiet. A milk ejection was recognized by an increasing grunting rhythm of the sow and rapid mouth movements of the piglets (Whittemore and Fraser, 1974). These sucklings were registered as successful (SS). The starting time and success of the second suckling were registered; 91 out of 98 observed sucklings could be defined as successful or unsuccessful (US). The percentages of successful and unsuccessful sucklings were counted for each sow and each later period. Forty-seven suckling intervals were observed. One sow had an interval ex-
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ceeding 240 min between the 8th and the 12th hour (not used in calculations), and one suckling interval is missing from the last period of one sow. The suckling intervals were divided into four categories: SS-SS, SS-US, U S US and US-SS, and counted from the start of the previous suckling to the beginning of the next one. The average weight gain of the A and B piglets was counted for the later periods in connection with SS. The total weight gain at the end of the 24 h was calculated. In the statistical testing of weights we used the two-tailed paired t-test for pair differences. All variations are given as 1 s.d. RESULTS
The 5-h period (1-5 h afterfarrowing) Weight gain intervals'. The percentages of G, N and L periods during the 5-h period and the average weight gain per piglet are presented in Table 1. There were no significant differences between the A and B piglets. The intervals between the G periods during the first 2 h of litter age after the birth of the first piglet were significantly shorter per piglet ( 14_+ 9 min, n = 32) than the intervals during the following 3 h (20_+ 19 min, n = 92, P<0.01).
Weight gain. Not all piglets gained weight during the observation hours. During the 2nd hour of piglet age the average weight gain for all piglets was 32 +_30 g, which was significantly more than during the 1st hour (9 + 37 g) and the 3rd-5th hours ( 14 + 26 g, 9 _+29 g and 17 _+22 g, respectively, P < 0.05 ) (Fig. 1 ). There were no significant differences in gain between the 3rd, 4th and 5th hours. On the other hand, the average weight gain for those piglets that did gain weight during the 1st (44%) and the 2nd (75%) hour was on average 44.5 +_0.7 g. This was significantly more than the weight gain during the folTABLE 1 The percentages of G (gain), N ( neutral ) and L ( loss ) periods, their variation and the average weight gain per piglet during the 5-h period % Of periods
G N k
Variation (%)
X
S
19 33 46
Il 13 19
Weight gain (g) S
.V
5-33 16-49 12-80
12.0 1.7 -2.8
4.6 0.4 1.3
325
W E I G H T GAIN PATTERN IN PIGLETS
70
W~ o
~ 4o [
3o
C
20
..............
:
h io
fl
n o g e -io -20 -30 2
4
Hours Fig. 1. The average weight change (g) and standard deviation per piglet and per hour of piglet age for all piglets (A) and for piglets that actually gained weight (B) during the first 5 h after the birth of the first piglet. TABLE 2 The average weight gain (g) and standard deviation per piglet and per hour of litter age for all piglets and for piglets that actually gained weight during the first 24 h after the birth of the first piglet Litter age (h) Weight gain of all piglets
x s
% of piglets gaining weight Their weight gain
x s
1
2
3
4
5
8
12
16
20
24
10 39
29 31
15 26
11 29
20 26
11 30
4 32
3 25
8 31
-6 33
46
69
69
60
65
65
60
55
55
37
45 37
45 23
29 18
27 25
33 23
26 26
25 16
21 16
32 15
23 26
lowing 3 h (28+ 18 g, 25_+28 g and 28_+ 18 g, respectively, P < 0 . 0 5 ) (Fig. 1 ). When counted by the hour of litter age, this weight gain pattern per hour and per piglet was similar for those piglets that gained weight (on average 62 _+ 10% ) and for all piglets (Table 2 ). Sixteen of the 20 piglets increased on average 98.9 + 67.5 g in weight during the 5-h period. Two A and two B piglets lost an average of 40.3_+ 4.2 g in weight from birth until the end of the 5-h period. One pair belonged to a sow which started to suckle 3 h after the birth of the first piglet. The other B piglet did not suck during this time and the other A piglet had only a couple of G periods. The total weight gain during the G and N periods during the first 5 h tended
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H. CASTREN ET a.L.
to be greater in the A piglets than in the B piglets ( 148 _+74 g and 108 _+79 g, respectively, n.s. ). However, the A piglets lost significantly more weight during the L periods than did the B piglets (66 _+28 g and 42 _+ 19 g, respectively, P < 0.05). The A piglets lost on average 45% and the B piglets 39% of their total weight gain. There were no differences in birth weight between the A and B piglets. Those A and B piglets that were heavier at birth ( > 1500 g, n = 8) tended to gain more weight ( 113.8 _+94.2 g) during the first 5 h than the middle-weight piglets ( 1300-1500 g, n = 6 ), which gained more ( 57.3 _+56.5 g) than the small piglets ( < 1300 g, n = 6, 46.3 _+66.0 g). There were no significant differences between these weight gains.
The later periods (8-24 h after farrowing) Suckling success. O f the sucklings observed, 53 _+ 17% were unsuccessful. The a m o u n t of US varied from 12 to 73% between the sows. The percentage of US was 50%, 44%, 60%, 52% and 61% for the later periods, respectively. The average weight gain per piglet during the observed SS was 19.7 + 9.4 g. There were no significant differences between' the sows, the later periods, or the A and B piglets.
Suckling intervals. The interval length between all types of sucklings varied from 8 to 105 min. The mean suckling interval for all sows was 35 _+22 min. There were no significant differences between the later periods ( 32 _+23 min, 34_+21 min, 40_+25 min, 31 + 12 min and 39_+27 min, respectively). However, there were significant differences between some sows in their mean interval lengths during the later periods. The interval length was on average 38_+23 min (range 12-91 m i n ) between SS-SS and on average 21 + 11 min (range 8-44 m i n ) between U S - U S . The mean suckling interval length after a SS was 35 _+21 min and after an US 23 +_24 rain. There were no significant differences between the SS-SS, SS-US U S - U S and US-SS intervals, although a preceding US tended to shorten the interval to the next suckling.
Weight gain. During the 8th-24th hours of litter age all piglets gained weighl on average 6.4_+ 3.2 g per period with no significant differences between the periods (Table 2 ). The percentage of piglets that actually gained weight during these hours declined from 65% at the 8th hour to 37% at the 24th h. These piglets gained an average of 25.4 _+4.2 g per period and per piglet, which was nearly as much as the gain during the first 3-5 h (Table 2). At the end of the first 24 h after the birth of the first piglet, 17 piglets out of 20 gained an average of 124.0_+ 89.0 g (range 4-277 g). There were no significant differences between the A and B piglets. Three piglets had a lower weight at this time than at birth (on average 48.7 __89.0 g).
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The A and B piglets with a birth weight over 1500 g gained significantly more weight ( 138.5 +_ 103.1 g) during their first 24 h than the smallest piglets with weights < 1300 g (34.1 _+54.7 g, P < 0.05 ). The piglets with a birth weight of 1300-1500 g gained 126.7 + 100.3 g. DISCUSSION
Even though we did not weigh the whole litters, the weight gain of the A and B piglets indicate that birth time, weight or order did not affect the weight gain during the 5-h period, in agreement with Hemsworth et al. (1976). Heavier piglets gained significantly more weight during the first 24 h than the smaller piglets. Hartsock and Graves (1976) have reported that the first piglets are heavier at birth and may thus suckle more frequently and grow better than lighter piglets born later. The intervals between the G periods were significantly shorter during the first 2 h of litter age compared with the following 3 h. Moreover, the largest amount of milk was consumed during the first and the second hour of both piglet and litter age. Most piglets gained weight during the second hour of piglet age. Our results suggest that piglets gain weight with certain intervals, in bouts, during the first 5 h after the birth of the first piglet. This confirms the results of Fraser (1984), who reported that about 2 h after the birth of the first piglet the milk ejections (2-20 g / m i n ) during hand-milking appeared at intervals of 5-30 min. These ejections lasted 1-4 min and were sometimes associated with birth of a piglet, body movements of the sow or other events such as squealing of piglets, or nursing of other litters. In farrowing sows only single teat stimulation seems to be sufficient for milk ejection. Possibly this is due to a low threshold for oxytocin release which is spurt-like (Fraser, 1984) just as later in lactation, when sucklings appear at more regular intervals (Ellendorffet al., 1982 ). Our results imply that milk is ejected in longer spurts with higher yield and triggered more easily and frequently than later during sucklings. The piglet weight loss per 5-min period was usually a few grams. These losses can arise from respiration, loss of saliva, mucus and other body debris. However, greater losses in weight arise from urination and defecation and also from errors involved in the weighing process (Barber et al., 1955 ). These defects were not corrected in our study. We did not have the heat lamp on during the first observation hours, which might have affected weight gain as the temperature ranged from 17 to 20°C. However, the lamp was kept on after the first 5 h. In addition, straw was placed in the pens. The piglets had constant free access to the sow's udder. The weight gain per G period in our study was similar to that found by Le Dividich and Noblet ( 1981 ) for piglets in cold conditions several hours after farrowing while during the later periods
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the gain in our study was greater per suckling than reported for piglets in warm conditions (Le Dividich and Noblet, 1981). Half of the weight gained was lost during the 5-h period in our study. The significantly greater loss in the A piglets might be due to the longer observation period in that group and consequently to the larger number of L periods compared with the B piglets. Full stomach increases the length of resting and suppresses the milk consumption of the piglets (Stephens, 1975). This m a y explain why A piglets were often asleep for a couple of hours after the initial active period of their life while the B piglets were still active at the udder. About 50% of the later sucklings were unsuccessful. Most sucklings, whether SS or US, had a nearly equally long interval, suggesting that there are in all sucklings some satisfying elements for both the sow and the piglets. A relatively high number of US were observed also in semi-natural conditions during the first 3 days after farrowing (Newberry and Wood-Gush, 1985; Castr6n et al., 1989a). The suckling intervals were of about the same length as in the present study (Castr6n et al., 1989a), suggesting that the suckling success of the indoor sows kept in conventional pens is not much affected by the suckling behaviour of other litters or indoor conditions. The function of US during the first days of lactation might be to increase milk production, as several lactogenic and gastrointestinal hormones have been shown to be released in response to teat stimulation by piglets (Uvn~is-Moberg et al., 1984; Algers et al., 1989). Uvn~is-Moberg and Winberg (1989) reported that non-nutritive sucking may also increase hormone release in children and improve their growth and development. Perhaps this is true also for piglets. The percentage of piglets that gained weight in our study during the later periods declined towards the end of the 24 h. The average weight gain in these piglets was nearly the same as during the first 3-5 h, in agreement with Hemsworth et al. (1976). CONCLUSIONS Piglets gained weight in bouts during the first 5 h of their life and at shorter intervals during the first 2 h than during the following hours. There were many piglets that did not increase in weight every hour, but those who did, gained about 45 g during both the first and the second hour of piglet age and about 25 g during the following 3 h. During the 8- to 24-h periods after farrowing the weight gain per piglet was about 25 g per period. During this time about 50% of the sucklings were unsuccessful. Similar results in a semi-natural environment suggest that environmental factors do not affect suckling success in indoor sows kept in conventional pens. ACKNOWLEDGEMENTS We wish to thank Mr. Fredrik Schulman for allowing us to use his farm in
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our research. The study was supported by a grant from the Finnish Veterinary Association. REFERENCES Algers, B., Madej, A., Rojanasthien, S. and Uvn~is-Moberg, K., 1989. Quantitative relationships between suckling-induced teat stimulation and the release of prolactin, gastrin, somatostatin, insulin, glucagon and VIP in sows. In: B. Algers (Thesis), Vocal and Tactile Communication During Suckling in Pigs. Aspects on Functions and Effects of Continuous Noise. Rapport 25, Skara, pp. 97-121, Barber, R.S., Braude, R. and Mitchell, K.G., 1955. Studies on milk production of Large White pigs. J. Agric. Sci., Camb., 46:97-118. Castrdn, H., Algers, B. and Jensen, P., 1989a. Occurrence of unsuccessful sucklings in newborn piglets in a semi-natural environment. Appl. Anita. Behav. Sci., 23: 61-73. Castrdn, H., Algers, B., Jensen, P. and Saloniemi, H., 1989b. Suckling behaviour and milk consumption as a response to sow grunting in newborn piglets. Appl. Anim. Behav. Sci., 24: 227-238. Curtis, S.E., 1974. Responses of the piglet to perinatal stressors. J. Anita. Sci., 38:1031-1036. De Passill6, A.-M. and Rushen, J., 1989. Using early suckling behavior and weight gain to identify piglets at risk. Can. J. Anim. Sci., 69: 535-544. Dyck, G.W. and Swierstra, E.E., 1987. Causes of piglet death from birth to weaning. Can. J. Anim. Sci., 67: 543-547. Ellendorff, F., Forsling, M.L. and Poulain, D.A., 1982. The milk ejection reflex in the pig. J. Physiol., 333: 577-594. English, P.R. and Morrison, V., 1984. Causes and prevention of piglet mortality. Pig News Inform., 5: 369-376. English, P.R. and Smith, W.J., 1975. Some causes of death in neonatal piglets. Vet. Annu., 15: 95-104. Fahmy, M.H. and Bernard, C., 1971. Causes of mortality in Yorkshire pigs from birth to 20 weeks of age. Can. J. Anim. Sci., 51: 351-359. Fraser, D., 1984. Some factors influencing the availability ofcolostrum to piglets. Anim. Prod., 39:115-123. Fraser, D. and Lin, C.S., 1984. An attempt to estimate teat quality of sows by hand milking during farrowing. Can. J. Anim. Sci., 64:165-170. Frascr, D., Nicholls, C. and Fagan, W., 1985. A sow milking machine designed to compare to yield of different teats. J. Agric. Eng. Res., 31:371-376. Hartsock, T.G. and Graves, H.B., 1976. Neonatal behaviour and nutrition-related mortality in domestic swine. J. Anim. Sci., 42: 235-241. Hemsworth, P.H., Winfield, C.G. and Mullaney, P.D., 1976. Within-litter variation in the performance of piglets to three weeks of age. Anim. Prod., 22:351-357. Le Dividich, J. and Noblet, J., 1981. Colostrum intake and thermoregulation in the neonatal pig in relation to environmental temperature. Biol. Neonat., 40:167-174. Lewis, N.J. and Hurnik, J.F., 1985. The development of nursing behaviour in swine. Appl. Anim. Behav. Sci., 14: 225-232. Newberry, R.C. and Wood-Gush, D., 1985. The suckling behaviour of domestic pigs in a seminatural environment. Behaviour, 95:11-25. Nielsen, N.C., Bille, N., Svendsen, J. and Riising, H.-J., 1976. Sygdomsbekaempelse i svinebesaetninger. Inst. Int. Med., Den Kgl. Veterinaer- og Landhojskole, Kobenhavn. Simensen, E. and Karlberg, K., 1980. A survey of preweaning mortality in pigs. Nord. Veterinaermed., 32:194-200. Stephens, D.B., 1975. Effects of gastric loading on the sucking response and voluntary milk intake in neonatal piglets. J. Comp. Physiol. Psychol., 88: 796-805.
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Thompson, B. and Fraser, D., 1988. Variation in piglet weights: weight gains in the first days after birth and their relationship with later performance. Can. J. Anita. Sci., 68:581-590. Uvniis-Moberg, K. and Winberg, J., 1989. Role for sensory stimulation in energy economy of mother and infant with particular regard to the gastrointestinal endocrine system. In: E. Lebenthal (Editor), Textbook of Gastroenterology and Nutrition in Infancy. Raven Press, Ltd., New York, NY, 53. Uvn~is-Moberg, K., Eriksson, M., Blomquist, L.-E., Kunavongkrit, A. and Einarsson, S., 1984. Influence of suckling and feeding on insulin, gastrin, somatostatin and VIP levels in peripheral venous blood of lactating sows. Acta Physiol. Scand., 121 : 31-38. Whittemore, C.T. and Fraser, D., 1974. The nursing and suckling behaviour of pigs. It. Vocalization of the sow in relation to suckling behaviour and milk ejection. Br. Vet. J., 130: 346356. RESUME Castr6n, H., Algers, B. et Saloniemi, H., 1991. Evolution du gain de poids des porcelets au cours des premieres 24 heures aprbs la naissance. Livest. Prod. Sci., 28:321-330 (en anglais). Les variations du gain de poids des porcelets ont 6t6 6tudi6es afin de mieux comprendre l'dvolution de la consommation de lair au cours des premibres 24 h apr6s la naissance. Le l er (A) ct le 6me (B) porcelcts de 10 truies 6talent pcses routes les 5 rain pendant les cinq premi6rcs heures, puis avant et apr6s la premi6re t6t6e observ6e au cours d'intervalles de quatre heures dc temps (les derni6res p6riodes) apr6s la naissance du premicr porcelet. En moyenne, tous les porcelets gagnaient 12 g de poids par h-coups separ6s par des intervalles plus courts ( 14 min ) duranl les deux premibres heures d'fige que pendant les trois heures suivantes (20 rain). En moyenne, le gain 6tait de 45 g pendant la premi6re et la deuxibme heures de vie, et de 25 g pendant ies 3 suivantes. Environ 50% des t6t6es 6taient r6ussies pendant les dernibres p6riodes et le gain de poids moyen du porcelet 6tait de 20 g par t6tee. L'intervalle moyen entre t6tces 6fair de 35 min. Les porcelets les plus lourds h la naissance ( > 1500 g) gagnaient significativement plus de poids que les plus 16gers ( < 1300 g) au cours des 24 premi6res heures. Les porcelets nouvcaux-n6s semblent gagner du poids par a-coups. Ce gain est plus important pendant les deux premibres heures que par la suite. KU RZFASSUNG Castr6n, H., Algers, B. und Saloniemi, H., 1991. Die Gewichtsentwicklung der Ferkel w~ihrend der ersten 24 Stunden nach dem Ferkeln. Livest. Prod. Sci., 28:321-330 (aufenglisch). Die Gewichtsentwicklung neugeborener Ferkel wurde untersucht, um besser zu verstehen, wieviel Milch w~ihrend und 24 Stunden nach dem Ferkeln verbraucht wird. Das erste (A) und das sechste ( B ) Ferkel von zehn Sauen wurde in 5-Minuten-lntervallenw~ihrend der ersten fiinf Stunden sowie vor und nach dem ersten Saugen in 4-Stunden-lntervallen (die sp~iteren Perioden ) nach der Geburt des ersten Ferkels gewogen. Im Mittel wuchsen alle Ferkel 12 g in Runden mit kiirzeren Intervallen (14 Minuten) w~ihrend der ersten beiden Lebensstunden als in den folgenden 3 Stunden (20 Minuten). im Mittel war der Zuwachs fiber die ersten beiden Lebensstunden 45 g und fiber die folgenden drei Stunden 25 g. Etwa 50% der Saugeversuche war ergfolgreich w~ihrend der sp~iteren Perioden, und der mittlere Gewichtszuwachs je Saugakt war 20 g. Das Sauge-lntervall betrug 35 Minuten. Bei der Geburt schwerere Ferkel ( > 1500 g) hatten einen signifikant h6heren Gewichtszuwachs in den ersten 24 Studen als leichter geborene Ferkel ( < 1300 g). Neugeborene Ferkel scheinen in Schfiben zuzunehmen. Der Zuwachs ist w~ihrend der ersten zwei Stunden gr6Ber als in den folgenden Stunden.