Cinnamon bark oil and coconut oil emulsions modified small intestinal motility and barrier function in laying hens in an ex vivo experiment.

1. Plant extracts and oils are supplemented in diets for chickens due to their antimicrobial capacities; however, little information exists whether they influence intestinal motility and barrier function.2. The present study aimed to determine the effect of increasing levels of cinnamon bark oil (CBO; 0%, 0.038%, 0.076% and 0.151%) and coconut oil emulsions prepared with soy and sunflower lecithin on the contractile function of enteric wall muscles in the jejunum and ileum and jejunal barrier function in laying hens.3. For testing muscle contraction, mid-jejunal and ileal segments (n = 4 each per hen) from four laying hens were placed in a longitudinal orientation into isolated organ baths filled with Krebs buffer and fastened to force transducers. Muscle segments were induced to contract with acetylcholine and the effects of the oil emulsions on contraction were measured.4. For barrier function, distal jejunal pieces were stripped of serosa before mounting into Ussing chambers and recording changes in short-circuit current (ISC) and transepithelial tissue conductivity (GT) before and after addition of the respective emulsion.5. The CBO decreased the muscle tone, representing a relaxation of on average 36.2% and 42.6% for the jejunum and ileum, respectively, compared to before the addition (P < 0.001). Moreover, CBO linearly decreased the ISC and GT of the jejunal mucosa, indicating a greater absorption of anions and increased barrier function (P < 0.001). Only the coconut oil-sunflower lecithin emulsion relaxed the muscles, whereas both coconut oil-lecithin emulsions increased the ISC but reduced the GT of the jejunal mucosa, which suggested an increased cation absorption and decreased paracellular permeability, respectively (P < 0.05).6. In conclusion, CBO and coconut oil-lecithin emulsions showed the potential to increase jejunal barrier function, whereas CBO may be more efficacious to slow down digesta passage in the small intestine.

Modification of digesta pH and intestinal morphology with the use of benzoic acid or phytobiotics and the effects on broiler chicken growth performance and energy and nutrient utilization.

Two experiments, each consisting of 2 trials, were conducted to investigate the effect of feeding benzoic acid (BA) and turmeric meal (TM) individually or in combination (Exp. 1) or garlic meal (GM) and TM individually or in combination (Exp. 2) on growth performance, digesta pH, gut morphology, and nutrient utilization in broiler chickens. Diets consisted of a nutrient-adequate control diet and the control diet with added BA (2 g/kg), TM (10 g/kg), BA (1 g/kg) plus TM (5 g/kg), and BA (2 g/kg) plus TM (10 g/kg) in Exp. 1. In Exp. 2, in addition to the same control diet as Exp. 1, the control diet with added GM (10 g/kg), TM (10 g/kg), GM plus TM at 5 g/kg each, and GM plus TM at 10 g/kg each were used. Each treatment had 6 replicate floor pens with 10 chickens per replicate. On d 14, 5 broiler chickens from each floor pen were transferred to metabolism cages and continued on their respective diets. Body weight and feed intake data were collected on d 0 and 21, excreta were collected from chickens in metabolism cages on d 19 and 20, and ileal digesta were collected on d 21. Digesta pH was measured at the crop, proventriculus, jejunum, and cecum. Jejunum sections were collected from chickens in Exp. 1 to study gut morphology. In Exp. 1, only the combination of BA and TM tended (P < 0.10) to improve weight gain but there were no effects on G:F. The combination of BA and TM at both inclusion rates decreased (P < 0.05) digesta pH in the crop, jenunum, and ceca. There were no treatment effects on ileal DM or total tract DM retention, but supplementation of BA or TM alone or in combination increased (P < 0.01) apparent ME (AME) and nitrogen-corrected AME (AMEn) relative to the control diet. In Exp. 2, TM alone or combined with GM improved (P < 0.05) weight gain and G:F compared to the control. Supplementation of TM alone or in combination with GM at the rate of 10 g/kg each reduced (P < 0.05) digesta pH in the crop, proventriculus, and ceca but had no effect at the jejunum. The combination of GM and TM improved (P < 0.01) ileal DE, AME, and AMEn. In conclusion, BA, TM, and GM individually or in combination with wheat-soybean meal based diets adequate in nutrients and energy selectively improved growth performance, modified digesta pH and intestinal growth, and increased the efficiency of dietary energy use.