Supplementing autolysed yeast improves weaners’ health

A team of Brazilian researchers evaluated the impact of substituting blood plasma with autolysed yeast in the diets of weaner piglets. The researchers published their findings in Animals.

Blood plasma is a source of protein in a weaners’ diet. It contains high levels of vitamins, minerals, and immunoglobulins. However, using blood plasma in the diet of weaners increases the cost, thus limiting higher levels of dietary inclusion. On the other hand, the yeast, Saccharomyces cerevisiae, is a source of products with probiotic and prebiotic activity which improves performance and immune function of weaners.

About the study

The team selected 240 male and female piglets for this trial that lasted 42 days. They divided the nutritional program into the following 4 phases:

pre-initial I (21–28 days of age);
pre-initial II (29–35 days of age);
initial I (36–42 days of age);
initial II (42–63 days of age) based on feed intake and age criteria.

They applied the following treatments within the first 3 nutritional phases:

control diet plus blood plasma;
control diet plus autolysed yeast;
control diet plus autolysed yeast and immunomodulator;
control diet containing 50% blood plasma plus 50% autolysed yeast.

They recorded temperature and relative humidity, daily weight gain, daily feed intake, feed conversion ratio, and diarrhoea score. Then, they evaluated blood parameters, gut permeability, and gut microbiota. In addition, they administered antibiotics and anti-inflammatory drugs to manage diverse health challenges encountered during the experimental period.

Piglet performance

Feeding autolysed yeast improved feed conversion ratio for piglets. However, 3 weeks after weaning pigs fed either the yeast or autolysed yeast and immunomodulator showed a decrease in feed conversion ratio. The evaluation of the all-nursery periods did not show any adverse effects of supplementing autolysed yeast and blood plasma on performance parameters.

Gut health and blood parameters

Feeding autolysed yeast associated with the immunomodulator or with plasma had no impact on gut permeability or blood parameters but it reduced the need for medications. The yeast associated with the immunomodulator decreased the occurrence of diarrhoea. Furthermore, feeding autolysed yeast associated with the immunomodulator or with plasma increased triglycerides levels.

Gut microbiota

Feeding autolysed yeast associated with the immunomodulator increased the relative abundance of beneficial bacteria such as Lactobacillus, Collinsella and Bulleidia.

The authors concluded that “autolysed yeast both as a standalone ingredient and in combination with immunomodulators is an effective substitute for blood plasma in the diets of nursery-phase piglets”.