|LI, QINGYUN - Iowa State University|
|GABLER, NICHOLAS - Iowa State University|
|GOULD, STACIE - Iowa State University|
|PATIENCE, JOHN - Iowa State University|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2018
Publication Date: 12/20/2018
Citation: Li, Q., Gabler, N.K., Loving, C.L., Gould, S.A., Patience, J.F. 2018. A dietary carbohydrase blend improved intestinal barrier function and growth rate in weaned pigs fed higher fiber diets. Journal of Animal Science. 96(12):5233-5243. https://doi.org/10.1093/jas/sky383.
Interpretive Summary: Pork is an important protein source, and is in high demand globally. The ability of pigs to grow rapidly and efficiently is impacted my many variables including diet and immune activation. The gut is the site of nutrient absorption, but because of the large number of bacteria present in the gut, it can be vulnerable to immune activation. The addition of different compounds to the diet serves as a method to enhance nutrient uptake from the diet of pigs, and also alter immune activation at the gut. Pigs were fed a high fiber diet with and without the addition of enzymes involved in the breakdown of the fiber, which typically is not well digested by pigs. The addition of an ezyme blend to the pig diet enhanced pig body weight, and also reduced immune activation at the gut level. Collectively, the results provide useful information to pork producers on methods to enhance efficiency of their production systems, and improve animal health.
Technical Abstract: The objective of this study was to evaluate the effects of dietary xylanase (X) and a carbohydrase enzyme blend (EB: cellulase, beta-glucanase, and xylanase) on nutrient digestibility, intestinal barrier integrity, inflammatory status, and growth performance in weaned piglets fed higher fiber diets. A total of 460 pigs (6.43 plus/negative 0.06 kg BW; F25 times 6.0 Genetiporc) were blocked by initial BW and pens (n = 12 per treatment) were randomly assigned to 1 of 4 dietary treatments. The diets included a higher fiber control diet and the control supplemented with 0.01 percent X, 0.01percent EB, or both enzymes, arranged in a 2 times 2 factorial. The diets were based on corn, soybean meal, corn distillers dried grains with solubles (DDGS), and wheat middlings. Pigs had a 7-d adaptation period and consumed the same commercial diet. Pigs were fed the experimental diets for 28 d with free access to feed and water. Body weight and feed disappearance were recorded weekly. One pig with BW closest to the pen average from each pen was selected and moved to metabolism crates on d 16 and orally administered a solution of lactulose and mannitol on d 22 followed by 12-h urine collection. Feces were collected from d 23 through 25. Intestinal tissues and mucosal scrapings were collected on d 28. Data were analyzed using PROC MIXED of SAS (9.4). Xylanase, EB, and their interaction were fixed effects and block was a random effect. The EB, but not X, increased pig BW and improved ADG over 28 d (P less than 0.05). Neither carbohydrase impacted ADFI, G:F, or apparent total tract digestibility (ATTD) of DM, GE, or CP. The EB improved ATTD of ADF (32.45 vs. 26.57 percent; P less than 0.01), but had no effect on NDF. Unexpectedly, X reduced ATTD of NDF and ADF (P less than 0.01). The EB reduced urinary lactulose:mannitol and increased ileal claudin-3 mRNA abundance (P less than 0.05), indicating improved small intestinal barrier integrity. There was a X times EB interaction on ileal secretory immunoglobulin A (sIgA) concentration (P less than 0.05); in the absence of X, EB decreased sIgA compared to the control, but this effect disappeared in the presence of X. The EB also reduced ileal IL-22 mRNA abundance (P less than 0.05), probably indicating decreased immune activation. In conclusion, EB but not X enhanced growth rate of nursery pigs fed higher fiber diets, which may be partly explained by the improved small intestinal barrier integrity and reduced immune activation, rather than improvement in nutrient digestibility.