# Glucose Injections at Birth, Warmth and Placing at a Nurse Sow Improve the Growth of IUGR Piglets
## 4 Discussion  
This experiment was designed to study the effect of giving an energy supplement--such as glucose or colostrum--at three time points during the first 24 h of life on the subsequent growth performance of IUGR piglets. Intrauterine growth-restricted piglets have a much higher mortality rate (up to 60%) than normal piglets within the first 48 h of life [3] and management strategies could be one way to improve survival. In the present experiment, 38% died before day 21. This suggests that management interventions can prevent a substantial amount of IUGR piglets from dying. It is, however, imperative that interventions are easy to perform and not too time consuming for them to be relevant for the farmer. The results demonstrated that giving glucose injections or a colostrum bolus in combination with heat and placement at a nurse sow did, overall, result in a small increase in whole-blood glucose concentration, but with no differences found in rectal temperatures during the first 24 h. At weaning, however, the IUGR piglets receiving glucose injections were heavier than the other treatments. All of the piglets were exposed to one hour of heat to increase body temperature--as this is vital for survival [12]--and were placed at a nurse sow to eliminate competition from larger littermates. This experimental design does, however, mean that it is not completely possible to elucidate the effects of these different factors. In addition, a true control to the glucose injection would have been a saline injection. However, as the aim was to simulate an on-farm situation, this was decided upon as being too invasive as a control group. This does, however, limit the interpretation of this study. What can be concluded though, is that energy, warmth and the removal of competition are valuable management tools in preventing IUGR piglets from dying and in giving them the best possible opportunities for growth. In the present experiment, 20 mL of porcine colostrum was administered three times. The allocation of 20 mL per treatment was based on a recommendation from [PERSON] and [PERSON] [16], who found that the maximum capacity of a 1 kg piglet's stomach was 34 mL when inflated to the absolute maximum. Figure 3: Overall rectal temperature values over the first 48 h for IUGR piglets. The values presented are least squares means \(\pm\) SEM. Other studies that have tried to enhance the colostrum intake of piglets to increase their growth have primarily focused on supplementation with porcine colostrum [14; 17; 18]. Body weight gain was found to increase when low birth weight piglets were given one oral supplementation of 15 mL of porcine colostrum [17]. This was not the case in the present study, where COLOS did not result in a higher BW compared to the WATER group. Piglets dehydter very quickly and it can be speculated that the WATER group in fact became more hydrated [14] and that this is part of the reason that no difference was found compared to the COLOS group. Further, it can be speculated that the colostrum treatment in the COLOS group reduced suckling motivation or that using colostrum supplementation as a mean of increasing the BW of IUGR piglets is simply not enough, and that a more direct energy source such as a glucose injection is more efficient. Both GLUC and GLUC + COLOS ended up with a higher BW at day 21, supporting this hypothesis. This difference shows that IUGR piglets given a glucose injection in some way had extra energy, which is perhaps necessary to compete at the udder or to use towards growth. Impaired growth in IUGR piglets has been coupled to a functional defect in the Insulin-like growth factor-system (IGF-system) [19]. Intrauterine growth-restricted piglets do not exhibit the same levels of IGF-1 in the plasma, in skeletal muscle, or in the mucosa of the gastrointestinal tract [20], nor do they exhibit the increased pattern of IGF-1 in the pre- and post-natal transition period [21] compared to their normal littermates.