Sows and gilts digest energy differently, study finds
Gestating sows have higher digestion efficiency than growing gilts
By Kate Ayers
University of Illinois researchers discovered that gestating sows have a higher digestion efficiency than growing gilts, according to a release from the university on Thursday.
The department of animal sciences analyzed the causes of this difference in energy digestibility.
“Growing pigs are allowed to eat as much as they want, but sows are generally restricted in their feed intake,” professor Hans Stein said in the release.
“This (restricted diet) may affect the absorption of nutrients from the digestive tract and thereby increase the efficiency of digestion.”
The experimental design allowed researchers to examine separately the effects of physiological stage and feed intake level.
Scientists fed corn, soybean meal, and rice bran diets to three different groups. The treatment groups included 24 growing gilts fed 3.5 times their maintenance energy requirement, 24 gestating sows fed 3.5 times maintenance, and 24 sows fed 1.5 times maintenance, according to the release.
The concentrations of digestible and metabolizable energy in diets were higher for gestating sows than for gilts, results showed.
Indeed, sows and gilts digest nutrients and energy differently, the study found. “However, (the results also) provide evidence against the hypothesis that level of feed intake is responsible for the difference,” Stein said.
Researchers did not detect any differences between sows fed 3.5 times maintenance and sows fed 1.5 times maintenance in the apparent total tract digestibility of gross energy, dry matter, organic matter, or neutral detergent fibre, according to the release.
Although previous studies have attributed sow’s higher energy digestibility to more efficient fibre fermentation in the large intestine, this study found that the sows did not digest fibre any more efficiently than growing gilts, according to Stein.
Rather, Stein hypothesized a different cause of the difference in digestibility between genders.
“It is possible that sows digest starch or lipids more efficiently than growing pigs, but we would need to do more research with ileal cannulated animals to test that hypothesis,” Stein said.
The Ilieal cannulation technique uses a T-cannula, which is a tube that can be inserted into the animal to gather data. The device is surgically inserted into the sow’s ileum to collect chymus samples. These samples are used to determine the apparent digestibility of nutrients, according to a PubMed article.
The full study is published in the Journal of Animal Science.