Energy reserves and mortality in newborn pigs
Experiment 1: 32 first cross (Landrace x Large White) (LR x LV) 2nd-6th parity sows were randomly allocated in two groups, 16 sows in each, given either 29.3 MJ or 51.0 MJ of DE daily for the last 10 days of pregnancy. The purpose was to determine the effect of either level of energy intake during the last 10 days or pregnancy or length of gestation on body glycogen and fat of the off-spring at birth. The level of feeding during the last 10 days of pregnancy and the length of gestation of the sow had no effect on glycogen and fat content of the liver, carcass or the whole body of the newborn pigs, or on the birth weight of the piglet. Experiment 2: 1181 piglets were used, born from 107 first cross sows of 1st to 6th parity. One group of piglets was treated with glucose, one with saline and one group was left as within litter controls. The aim of the experiment was to see if sufficient augmentation of the energy reserves in piglets would reduce mortality. Experiment 3: 1894 piglets were randomized to one of the 5 groups. Pig mortality from birth to 1 week of age was lower in pigs which received 4g of glucose. Experiment 4: 1994 piglets were randomly allocated in one of the 5 groups. Pigs from sows which had been induced to farrow had a significantly higher mortality than those from natural births. Experiment 5: The total of 1958 piglets was used, born from 190 sows which farrowed naturally. The object was to find out to which extent 6g of glucose could improve survival in pigs during the first week of life. Piglets given glucose had a lower mortality. Experiment 6: The object of this experiment was to find out the concentration of glucose in the blood of piglets reared naturally up to 1 week of age. Seventeen pigs were used, born from 2 sows which farrowed after induction of parturition. Blood glucose concentration was low at birth but it increased significantly up to 14 hours after birth. Experiment 7: Fourteen piglets were used, from which 6 piglets were injected with an amount of glucose. The amount of glucose was defined as the amount required to supply sufficient energy to cover 1.5 times the heat lost in the first 24 hours of life. At 1.5 hours after birth blood glucose concentration reached highest values for both groups. Blood glucose concentration remained high in piglets given glucose for about 15 hours compared with the value at birth, but at the end of the first 24 hours both groups had similar concentrations which were lower from those recorded at birth for the pigs. Experiment 8: Ten piglets from 1 sow were allocated to be given glucose, saline, or left as controls. At birth all piglets were bled and the injection was given, which was given again at 24 and 48 hours after birth. Blood glucose concentration in piglets given glucose increased 2 hours from each injection; but the response to the injection decreased from the first to third injection. Experiment 9: Piglets from 3 sows were allocated to one of the 4 treatment groups. Piglets in the G/2 group increased blood glucose concentration at 1.5 hours after the injection. The increase in blood glucose concentration of the piglets in the G/4 group was similar to that of the pigs in either the S/2 group or the controls. The conclusion was that the G/4 treatment was not an effective dose of glucose. Experiment 10: Fifteen piglets from 2 sows were randomly allocated to one of the five treatment groups. The concentration of total serum protein increased in all groups from birth to 24 hours with a small decrease from 24 to 48 hours. The control pigs had always higher values of total serum protein concentration compared with pigs given glucose or saline. Experiment 11: Thirty piglets born from 4 sows were used, which were randomly allocated to be in the G, S/2 or in the control group. Pigs were injected with glucose or saline at birth and at 24 hours. Experiment 12: Seven sows were catheterised in the ear vein. Five sows farrowed naturally and 2 sows farrowed after induction of parturition with PG which was injected 24 hours before the predicted date due. Experiment 13: 29 piglets born naturally and 17 piglets born from induced farrowings were used. Piglets were bled at birth and blood was collected for blood glucose and plasma FFA determination. Piglets born naturally had higher concentrations of blood glucose and lower concentrations of plasma FFA.