NUTRITION ▶▶▶
Quality colostrum boosts immunity transfer
P BY JENNIFER MAURIN AND DR SÍGFRID LÓPEZ, PANCOSMA, SWITZERLAND
iglets are partially immunocompetent from the mo- ment they are born, more specifically from day 70 of gestation. But this ability is not yet fully developed and appears immature both during birth and after-
wards. Therefore, complete protection for piglets is ensured by the exposure of piglets after birth to high levels of patho- gens, forcing their immune system to mature and become fully competent in a very short period of time, and by the passive transfer of antibodies from the mother, through the colostrum, thanks to the action of specific hormones during peri-birth (see Figure 1). This transmission of maternal antibodies is crucial, as the type of placenta in sows (epitheliochorial) is radically different to the placenta of humans or primates. It doesn’t allow for the trans- mission of any type of immunoglobulins. Nevertheless, piglets already have antibodies in their bloodstream at birth; they gen- erate these antibodies themselves after having been in contact with antigens during the final month of gestation. These anti- bodies generated by the foetus are not enough to adequately protect it after birth. This has led to a range of different vaccina- tion strategies for sows in order to boost the generation and transmission of antibodies via the colostrum, which will then be consumed by piglets after birth. The piglet is highly depend- ent on the colostrum for protection, and piglets that die during peri-birth, have a lower serum level of antibodies.
Colostrum: source of immunoglobulins The colostrum contains a battery of defence cells to help the piglet survive. The level of immunoglobulins in the colostrum is 60 times higher than in the milk. Around 65-90% of these immunoglobulins consist of the IgG type, which provides sys- temic protection. The absorption of these IgG immunoglobu- lins by piglets is not selective; they are present in the plasma two hours after colostrum ingestion and peak at 12 hours. The immunoglobulin profile of colostrum is dependent on the antigens that the mother is exposed to. During lactation, IgG immunoglobulins are progressively re- placed by IgA, which functions to protect the intestinal mu- cus of the piglet. This is especially interesting, given that dur- ing this period, the intestine is the main target organ for many pathogens, such as E. coli.
Colostrum consumption is crucial for piglets to survive lactation. Traditionally, the efficiency of the immune system has been evaluated by farm veterinarians rather than by nutritionists. Recent publications identify dietary ingredients modulating immune functions, which point to new perspectives for nutritional strategies.
Given the enormous complexity of the factors which influ- ence the generation and assimilation of colostrum, the pig farming sector has implemented a series of strategies. One such strategy is immune-adaptation in sows. This is achieved by the controlled exposure of sows during their development towards becoming future mothers. This process trains the
Sows may re- quire a double or even a triple vaccination.
Figure 1 - Piglets are partially immunocompetent at birth.
Exposure to external environment stimulates piglets immune system
Day 70 of gestation
Piglet is partially immunocompetent
BIRTH
Piglet immunisation continues after birth.
Epitheliochorial placenta does not allow maternal immune transfer. Piglet generate its own antibodies.
Sow supplies IgG and IgA antibodies via colostrum
Piglet is protected by maternal antibodies
▶PIG PROGRESS | Volume 35, No. 6, 2019 29
PHOTO: HENK RISWICK
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36
