Artificial milk supplementation with increasing wheat levels in piglets

Health and productive impacts of early piglet weaning (how can they be mitigated?)

Preparing the gut for the transitional period of weaning (i.e. going from a diet of milk solids to vegetable ingredients) is an increasingly important matter, due to the need of producing robust healthy piglets that can be weaned without the excess use of zinc oxide or antibiotic growth promoters.

Early weaning of piglets is usually accompanied by severe growth reductions and diarrhea (Lalles, JP, et al., 2007) Typically, dry feed is offered to piglets before weaning in order to prepare the small intestine, to an increasing percentage of vegetable ingredients as well as preparing piglets for dry feed consumption. However, a large percentage of piglets do not eat offered feed (Bruininx., et al. 2002) and as a result, this type of management system limits the sow’s rearing capacity.

Modulating intestinal function through the use of a milk replacer

The provision of an artificial milk replacer may provide an opportunity to modulate piglets’ digestion and growth conditions, considering that the nutrient composition of the replacer will influence intestinal development, by affecting enzymatic activity and morphology. (Kelly, D, Smyth, et al. 1991) This can potentially increase feed intake in piglets before weaning, and improve SI maturation.

Wheat flour supplementation

Wheat flour, is a commonly used ingredient in artificial milk replacers, which leads to a shift in carbohydrates from lactose to a combination of lactose and starch. However, its effects on piglet intestinal function and health are still not well known. Therefore, although starch may have potentially beneficial effects on gut adaption, the early exposure of an immature intestine to complex carbohydrates may also compromise growth. Causing potential dysregulations in the immune function and inflammation.

Study

With the aim of clarifying some of these matters, the following study was carried out to investigate the effects of feeding piglets an artificial milk replacer with increasing levels of wheat flour. Evaluating its influence on growth performance, intestinal enzyme activity and immune function. This type of milk replacer diet, was compared to a diet based entirely on cow’s milk. It was hypothesized that the inclusion of a starch component (wheat flour) induces mucosal ripening, as measured by increases in digestive activity and improved integrity and immunity of the small intestine.

The experiment was carried out with respect to animal experimentation and with approval from the Danish Animal Experimentation Inspectorate. The study was performed at the experimental facilities at the University of Copenhagen, Frederiksberg campus.

Materials and Methods

To test this hypothesis, thirty-six piglets (males and females) were separated from the sow on the third day and fed pure artificial milk (MILK) or, from day 11, fed artificial milk with increasing amounts of wheat (WHEAT; 10% dry matter on day 11 to 40% dry matter on day 26). On days 25 and 26, blood samples were collected to determine cytokines. The pigs were euthanized to examine body fat, muscle mass and gut morphology, RNA sequencing and enzyme analysis.

Results and Discussion

• No differences in growth performance or body composition were observed between groups. Piglets in the (Wheat) group had higher enzymatic activity of maltase and sucrase in the proximal part of the small intestine compared to the (Milk) group.

• There were no differences in gut morphology, histopathology and gene expression between groups. More peripheral neutrophils were found in the (Wheat) group, suggesting a potential modulation of immune function.
• Lipopolysaccharide stimulation of peripheral mononuclear cells showed no difference in cytokine production between groups, suggesting that the various components of the diet did not induce systemic inflammation.

Conclusion

• In conclusion, piglets fed artificial milk with the addition of wheat evidenced immunological and maturation changes of their intestinal mucosal enzymes indicative of adaptation to a plant-based diet.
• The increased enzyme activity in the WHEAT group compared with the MILK group, together with the unchanged gut morphology, histopathology and gene expression, suggests that the piglets given a milk replacer with wheat do not experience detrimental health effects and instead may have higher activity of carbohydrases that are key to digestion of starch and other carbohydrates of vegetable origin.
• Researchers from this study believe, that nutrient-dense complex milk replacer supplementation might help piglets through the transition period at weaning by increased body weight and increased capacity for uptake of nutrients
• This type of supplementation was not associated with any clinical complications. However, more studies are necessary to establish whether this type of dietary management could improve weaning responses. Finally, researchers also encourage further investigation in solving the unanswered question of how do pigs perform after weaning when fed higher starch levels?

Source: Abstract from  “Pre-weaning adaptation responses in piglets fed milk replacer with gradually increasing amounts of wheat.” British Journal of Nutrition, 126