Effect of Levucell® SB on colostrums biochemical composition and antibodies concentration.

In his presentation, first of all Jean Le Dividich referred to the piglet´s characteristics after birth:

- It is born with a very low energy reserve: very thin (1 to 2% of adipose tissue, without "brown" fat)

- No immune protection (agammaglobulinemia) due to the lack of antibody permeability of the sow's epitheliochorial placenta.

These low energy reserves explain why 50 to 77% premature deaths (first 48 hours) are due to crushing: as the piglets do not consume colostrum fast enough, they are incapable of maintaining their homeothermy, become more and more feeble and are incapable of moving fast enough when the sow lays down (several authors have demonstrated the correlation between mortality rate during lactation and colostrum uptake).

 

Fig 1: The newborn piglet energy requirements during the first 24h

The essential energy reserves of the piglet at birth consist of liver glycogen (and secondarily muscle glycogen) which are almost 2.5 times

higher than those of a child at birth (in Kj/kg of weight). However, when we add the reserves represented by the fatty tissue, the child has 13 times more available energy (again by kg of live weight) than the piglet! The latter is born naked and wet into a difficult environment where about 25% of energy needs should be devoted to thermoregulation and 8% to physical activity (access to the teat, and so on). In case of an energy deficit, the piglet will have difficulty in keeping its body temperature, loses its reactive ability, reduces its sucking efforts, etc.

Afterwards, Jean Le Dividich pointed out that his calculations and multiple clinical trials showed that, in the first 24 hours, the piglet must consume 160 to 180 g of colostrum per kg of live weight at birth to assure its energy autonomy (on average a piglet weighing 1.4 kg at birth consumes 260 to 300 g of colostrum but with enormous variations: our clinical trials such as the ones carried out by Devillers ... show that individual uptake varies from 0 to 800 g per piglet! Jean Le Dividich then mentioned the factors of production variation and colostrum uptake: the limiting factor of colostrum uptake is not really the piglet, which, when fed with a bottle, can consume an average of 450 g, and every sow with no farrowing problems can produce enough colostrum for 12 piglets.  The amount of colostrum produced does not depend on the litter size (consequently the quantity per piglet will be reduced in large litters); but there is a clear relationship between the weight at birth and the ingested colostrum (on average +27 g of colostrum/+100 g of live weight at birth; the rank of birth does not seem to directly influence the total uptake of the first 24 hours, but the greatly deteriorated vitality of the piglets which suffered hypoxia is associated with a very low colostrum uptake.

In the second part of his presentation, Jean Le Dividich tackled the importance of colostrum in terms of immunity, and reminded the audience that the Ig G are in a majority in the colostrum, although there are significant differences between farms, and that their concentration drops (as does their IgM and A) very quickly in the first 24 hours after the birth of the first piglet. The transfer of antibodies to the piglet (measured through Ig serum analysis) is directly related to the quantity of colostrum ingested (and, of course, to the antibody abundance in the colostrum). So colostrum uptake must be made in a sufficient quantity to assure immune protection during the period in which the piglet is not self-sufficient and must be fast due to the "Gut closure" effect that describes the end of intestinal permeability to macromolecules after 24 hours. We should be aware that a minimum of 100 to 120 g of colostrum by kg of live weight at birth ensures the piglet's minimum immune protection.

In the last part of his presentation, Jean Le Dividich presented the first results of a trial carried out "in the field" to assess the effect on colostrum quality of distributing Levucell SB. 67 sows LWx LD either received or did not receive Levucell SB during the last 3 weeks of gestation (33 sows in a control group and 34 sows receiving Levucell SB, identical mean parity between the 2 groups), the colostrum was sampled after the birth of the first piglet and afterwards at 3 - 6- 12 and 24 hours. On average, the rate of Ig G in the colostrum of "Levucell SB" sows had risen by 21% (p<0.025, highly significant difference) but with almost 60% difference after 24 hours despite the especially high levels of antibodies! Similar results were achieved for the Ig A (p<0.08). For the IgM (but with levels 16 times higher than the ones for Ig G) the difference was only numerical and not significant.