Bromelain supplement boosts gut health in sows and piglet growth

Supplemental bromelain may bolster reproductive health, the immune system and growth performance for sows and piglets, say researchers from Dankook University. 

“The results indicated that dietary supplementation of bromelain in late gestation and lactation improved performance in sows and suckling piglets,”​ they said, adding that the additive could be used in an antibiotic-free program for sows and piglets.

The researchers from the animal resource and science department studied the effect of including different levels of bromelain-c.3.4.22.32 (BR) in the diet of sows and non-weaned piglets for a period of 28 days while seeking possible alternatives to antibiotics for growth promotion.  

“We hypothesized that BR supplementation in sow gestation and lactation diets could improve sow and litter performance,”​ said the researchers. “However, very few studies have examined the impact of bromelain in laboratory animals and humans, and the effect of BR on sows and piglets has not yet been studied.”​

Experiment details​

In the study, 96 sows were fed one of four diets starting on day 108 of gestation. The different diets included a control gestation diet of about 57% corn, 10.7% soybean meal and 12% wheat bran, along with rapeseed meal, rice bran, tallow, molasses, dicalcium phosphate, limestone, salt, L-lysine HCI and vitamins. The control lactation diet was comprised of similar amounts of the same ingredients, though the percentage of the two primary ingredients became 51.12% corn and 24.6% soybean meal, said the scientists.

In addition to the control group, the three other groups of sows received .5g/kg BR, 1g/kg BR or 2g/kg BR, they said. For five days, the diets also contained chromic oxide as an indigestible marker to allow for the calculation of apparent total track digestibility for dry matter, nitrogen and gross energy.

Each litter was standardized to 10 piglets using cross-fostering of piglets among sows in the same treatment group, the scientists reported. Piglets were weaned at 21 days.

Results ​

The group of pigs getting the diet with 2g/kg BR saw increased average daily gain and weaning body weight for piglets. They moved from an average birth weight of 1.49kg to a weaning weight of 6.95kg and had an average daily gain of 260g, reported the scientists.

“The piglets suckling sows fed with BR had linearly improved growth performance,”​ said the researchers. “This observation is possibly related to the increased serum IgG​ (immunoglobulin) concentrations in piglets suckling sows fed the BR diets, because the improved immunity may have positively effects on growth performance.”​

But there were no differences recorded for diarrhea score, piglet survival rate or still birth rate, they reported.

Sows getting any of the diets supplemented with BR had larger Lactobacillus​ population and a decrease in fecal E. coli​, said the scientists. This result suggested that the BR minimizes the effects of some intestinal pathogens.

The apparent total tract digestibility of nitrogen was greatest in the sows getting 2g/kg BR of supplemental BR. But researchers reported no difference in the apparent total tract digestibility of energy and dry matter for sows among the diets.

Additionally, the sow group getting the 2g/kg BR had lower blood urea nitrogen (BUN) and higher lymphocyte counts along with increased milk protein. Piglets of those sows also had lower blood BUN.

 “The feeding of diets with BR supplementation caused increase of the apparent total tract digestibility of nitrogen, the blood lymphocyte counts, and milk protein in the sows,”​ said researchers in the study. “In contrast, BR supplementation reduced blood BUN and SCC (somatic cell counts) in the sows and suckling piglets.”​

How the data was collected​

During the experiment, the body weight (BW) and backfat of sows were checked at the start, after farrowing and at weaning to determine body weight loss and backfat loss during the period, said the scientists. The feed consumed during gestation and lactation periods was recorded to establish average daily feed intake (ADFI).

The survival rate of the piglets was recorded, they said, and the piglets were weighed after birth and at weaning to establish average daily gain. Piglet fecal matter was examined three times a day and scored to track severity of diarrhea and a cumulative diarrhea score was established.

Additional fecal samples from 12 sows per group also were taken on day 21 and evaluated for amounts of E. coli​ and Lactobacillus​ along with apparent total track digestibility for dry matter, nitrogen and gross energy.

Blood samples also were collected from 12 sows per group and two piglets per sow at day 21 to establish levels of creatinine, BUN, IgG, red blood cells, white blood cells and the lymphocyte count, they said. Colostrum and milk from 12 sows per group also was collected after farrowing and on day 21 of lactation and analyzed for fat, protein, lactose and solids.

Future areas for study​

Given the outcomes produced in the study, the BR supplement could be tested as a promoter for non-weaned pigs as it can increase colostrum and milk composition during lactation, said the researchers.

“Our studies suggested that the addition of BR in gestation and lactation diets could positively affect the performance of sows because of the increased nutrient digestibility, gut health and improved immune system,”​ they reported.