Feed form and perch design do not interact to production performance, gastrointestinal tract traits, behaviour and welfare of laying hens reared in enriched cages.

1. It was hypothesised that perch material and design may affect utility and maintenance energy demand in laying hens, affecting their feed form preferences and daily feed consumption. Accordingly, perch design and feed form on hen performance, gastrointestinal tract functions and some behavioural and welfare-related traits were studied in laying hens (ATAK-S) reared in enriched colony cages from 24 to 40 weeks of age.2. The experiment was a 2 × 2 factorial investigating two perch materials and design (circular steel or mushroom-shaped plastic) and feed form (mash or crumble). A total of 396 hens were randomly assigned to one of the four treatment groups with nine replicates each (11 birds per replicate).3. Except for feeding behaviour and prevalence of foot pad dermatitis at 40 weeks of age, the modification of the perch design did not have a significant effect on the traits examined. Mushroom-shaped plastic perches reduced feeding behaviour (p < 0.01) and the incidence of foot pad dermatitis at 40 weeks of age (p < 0.001).4. Performance traits were not affected by feed form. Intake, final body weight and FCR for crumble-fed laying hens were greater than those fed mash (p < 0.01).5. Hens fed mash had higher (p < 0.01) relative gizzard weights along with lower (p < 0.05) pH values, pancreatic chymotrypsin, amylase and lipase activities (p < 0.05), and duodenal absorption surface areas (p < 0.01). Ultimately, this gave higher protein digestibility (p < 0.05) compared to those receiving crumble.6. In conclusion, in enriched cage rearing systems, mashed feed was preferred over crumble to efficiently maintain productive performance. Compared to circular steel, plastic mushroom-shaped perches were associated with better footpad health and welfare.

Evaluation of encapsulated sodium butyrate on growth performance, energy digestibility, gut development, and Salmonella colonization in broilers.

Two experiments were conducted to determine the effect of an encapsulated sodium butyrate (Na-B) with targeted releasing times on broiler performance, energy digestibility, intestinal morphology, and ceca Salmonella colonization. In experiment 1, 3 different Na-B products (CMA, CMP, and CMS) were evaluated following a challenge with a nalidixic acid-resistant Salmonella typhimurium (STNAR). Cobb-Cobb male birds were placed 8 per pen into 6 replicates for each treatment. Treatments included 6 Na-B treatments (500 and 1,000 ppm of each product) plus 2 control (non-challenged and challenged). Birds were orally gavaged with 0.1 mL of 107 cfu/mL STNAR on d 4. Ceca and ileal samples were collected on d 11. In experiment 2, CMA and CMP products were evaluated for a full grow-out period without an external challenge. Cobb-Cobb male birds were distributed among 45 floor pens with 24 birds per pen. Treatments included 4 product treatments (500 and 1,000 ppm of each product) plus one control. Feed intake and pen weight were obtained on d 14, 28, and 42. Experiment 1 showed that CMP at 1,000 ppm had the highest value for BW and BWG on d 4 (P = 0.07). Adding CMA and CMP at 500 ppm increased ileal digestibility energy (IDE) compared to the challenged control (P ≤ 0.05). The Salmonella recovery data indicated that the challenge had a significant but mild impact, since it did not affect the performance variables but did result in a significant increase in log10 cfu/g cecal material between the non-challenged and challenged control (1.42 vs 3.72). Experiment 2 showed that both products improved the villus height in the duodenum on d 21 (P = 0.08) and IDE on d 42, relative to the control (P ≤ 0.05). This study demonstrates that Na-B has the potential to improve growth in broilers at an early age. The beneficial effects on intestinal morphology and IDE are affected not only by dosage level, but also by the product's releasing time.