Dietary Inclusion Level Effects of Yoghurt Acid Whey Powder on Performance, Digestibility of Nutrients and Meat Quality of Broilers.

In recent years, the increasing demand for Greek strained yoghurt produced massive amounts of acid whey, which constitutes a major environmental pollutant. Whether yoghurt acid whey can be included in poultry diets is not known. The purpose of this study was to evaluate the effects of four dietary levels of yoghurt acid whey powder (YAWP) on the growth performance, nutrient digestibility, meat quality traits and oxidative stability. A total of 300 male 1-day-old Ross 308 broilers were assigned into four groups with five replicates of 15 broilers each: control-fed basal diet with no YAWP addition (WO) or basal diet supplemented with YAWP at 25 g/kg of diet (WA), 50 g/kg of diet (WB), or 100 g/kg of diet (WC). At the starter period, body weight and body weight gain were reduced after WB and WC treatments compared to the WO treatment. Breast meat oxidative stability was improved during refrigerated storage for 1 and 3 d in all YAWP treatments compared to control, while the WA treatment showed an improved oxidative stability after 6 and 9 d. The results suggest that YAWP inclusion at 25 g/kg of diet did not impair performance and extended the meat shelf life by reducing lipid oxidation rates.

Dietary phytogenic inclusion level affects production performance and expression of ovarian cytoprotective genes in laying hens.

A 12-wk study was conducted to investigate the effects of a phytogenic premix (PP) inclusion level on production performance, and the expression of genes relevant for detoxification (aryl hydrocarbon receptor; AhR) and antioxidant capacity (Nuclear factor erythroid 2-related factor 2; Nrf2) in the ovaries of laying hens. The PP consisted of bioactive substances derived from ginger, lemon balm, oregano, and thyme substances (Anco FIT-Poultry). Depending on PP inclusion level (i.e., 0, 500, 750, 1,000, and 1,500 mg/kg diet) in the basal diet, 385 laying hens Hy-Line Brown, 20-wk-old were assigned into 5 treatments: CON, P500, P750, P1000, and P1500, with 7 replicates of 11 hens with ad libitum access to feed and water. Performance parameters were closely monitored on a weekly basis and analyzed in the following 3 experimental periods: 1 to 4 wk, 5 to 8 wk, and 9 to 12 wk of treatment administration (i.e., 21-24, 25-28, and 29-32 wk of layers age, respectively). At the end of the 8th and 12th wk of the experiment (i.e., 28 and 32 wk of layers age), a layer from each replicate was selected, euthanized, the ovaries sampled and stored deep frozen until gene expression analysis. Data were analyzed by ANOVA and means compared using Tukey's honest significant difference test. Polynomial contrasts tested the linear and quadratic effect of PP inclusion levels. Results revealed that PP inclusion, improved (P < 0.05) laying rate and egg mass, compared to CON. Increasing PP inclusion level enhanced laying rate and egg mass, linearly and quadratically and peaked at P1000 (P < 0.05). In the ovaries, the AhR pathway genes assessed were down-regulated (P < 0.05) mainly at P1000 and P750 treatments. In addition, PP related cytoprotective potential was demonstrated via beneficial changes seen for the majority of the Nrf2-pathway genes assessed with the P1000 displaying most significant differences from CON. Conclusively, new data highlighted beneficial cytoprotective effects of PP inclusion on layer ovaries and documented further layer performance, with the inclusion level of 1000 mg PP/kg diet being the most prominent.

Phytogenic Effects on Layer Production Performance and Cytoprotective Response in the Duodenum.

The aim of this study was to evaluate the effects of a phytogenic premix (PP) on the production performance and critical genes relevant to the detoxification (i.e., aryl hydrocarbon receptor pathway) and antioxidant (i.e., nuclear factor erythroid 2-related factor 2 pathway) response in the duodenum of laying hens. The PP was based on bioactive substances derived from ginger, lemon balm, oregano, and thyme (Anco FIT-Poultry). A total of 385 20 week old Hy-Line Brown layers were assigned to five dietary treatments with seven replicates of 11 hens each for a 12-week feeding trial. The experimental treatments included a corn−soybean meal basal diet with no PP (CON) or supplemented with PP at 500 (P500), 750 (P750), 1000 (P1000), and 1500 mg/kg diet (P1500). The overall (1−12 weeks) laying rate (p < 0.001) and egg mass (p = 0.008) were significantly increased in the P1000 group compared with the CON. At the duodenum, increasing dietary PP inclusion levels beneficially affected (p ≤ 0.05) the expression of the majority of the AhR and Nrf2 pathway genes studied. In conclusion, according to the gene expression analysis, PP inclusion resulted in a reduced requirement for detoxification and an increased antioxidant capacity, with most of the effects seen at the PP inclusion range of 750 to 1000 mg/kg diet.