Although many methods have been developed in order to reduce the negative effects in laying hens reared at high cage density, researches on effects of dietary supplementation of oregano (Oreganum syriacum L., OEO) essential oil as a feed additive to the diets are extremely sparse. This study investigated the effects of OEO and caging density on performance parameters, egg quality criteria, some blood biochemical parameters, blood antioxidant capacity, and intestinal histopathology of laying hens. We used 276 white Lohmann laying hens aged 38–40 weeks in the experiment. The animals were divided to positive control (600 cm2 hen/cage, PC), negative control (360 cm2 hen/cage, NC), negative control+ 200 mg/kg OEO (NC+O2), negative control+ 400 mg/kg OEO (NC+O4), and negative control+ 600 mg/kg OEO (NC+O6). In this study, it was determined that egg weight and egg shell weight increased at higher caging density, but they did not change with dietary supplementation of OEO. In addition, the plasma calcium and phosphorus decreased with the higher caging density and dietary supplementation of OEO. Supplemented OEO to the diets of the laying hens reduced lipid peroxidation and improved antioxidant capacity and intestinal histopathology of laying hens. As a result, it was determined that OEO decreased the negative effects of high caging density. While this positive effect was found to be at a maximum dose at 400 mg/kg of OEO, it was determined that a dose of 600 mg/kg of OEO had a toxic effect, if even numerically.

The chemical composition, in vitro total gas and CH4 production and performance of cattle fed on factory black tea waste (Camellia sinensis) (BTW), alfalfa (Medicago Sativa), sainfoin (Onobrychis sativa) and white clover (Trifolium repens) was investigated. The gas production was quantified at the 24th hour of the incubation process. BTW was found to vary from roughages in chemical composition (p < 0.05). In addition, the roughages differed in terms of nutrient composition and gas production (p < 0.05). In legume roughages, acetic acid (AA), propionic acid (PA), butyric acid (BA), and total volatile fatty acids (TVFA) values ranged from 52.36–57.00 mmol/L, 13.46–17.20 mmol/L, 9.79–12.43 mmol/L, and 79.71–89.05 mmol/L, respectively. In comparison with black tea waste, legume roughages had higher values of AA, PA, BA, and TVFA. Black tea waste contained a higher acetic acid ratio than legume roughages when compared as a percentage. There was a similar ratio of propionic acid to the rate calculated for sainfoin (Onobrychis sativa) and clover (Trifolium repens), and a similar ratio of butyric acid to the ratio determined for alfalfa (Medicago Sativa). The current study shows that the 5.7–6.3% tannin content of black tea waste can be used in ruminant rations with high-quality roughages. Due to the fact that BTW reduces methane emissions from ruminants and eliminates energy waste from them, the environment can be improved. To obtain more reliable results, further animal feeding experiments on legume roughages and BTW are required.

Chemical composition of forage crops (35% hungarian vetch, 35% forage peas, 10% oats, 10% triticale, 10% wheat) of different harvest times and fertilizer applications at different doses, relative feed value (RFV), relative feed quality (RFQ , energy contents (ME, NEL), in vitro digestibility parameters (TNDFD, TOMD, TDN, DMI), in vitro gas production, methane (CH 4 ) production, fractionation factor (PF), microbial protein (MP) and microbial protein synthesis efficiency Ankom Daisy in vitro fermentation system and in vitro gas production technique were used in the research carried out to determine their effects on (MPSE) and true degree of digestion (TDD). Harvesting at different times significantly affected (P<0.05) the CP

This study aims to investigate using different ratios of urea-molasses in silage of food in vitro fermentation, feed value and quality production in feed. After being withered a little, the fodder plant was fragmented into 2-3 cm long pieces. 0, 2 and 4% molasses and 0, 0.5 and 1% urea were added. The treatment groups were UM1 (control), UM2, UM3, UM4, UM5, UM6, UM7, UM8 and UM9 supplemented with 0, 0, 0, 1, 1, 1, 1.5, 1.5, 1.5% urea and 0, 2, 4, 0, 2, 4, 0, 2, 4% molasses respectively, and a total of 54 silage samples, 9 × 6 parallel, were prepared, vacuumed in ready-made silage bags, and stored at 25 ± 2 °C for 60 days. After the silages were opened, pH, nutrient contents, Fleig scores (FS), in vitro digestibility parameters, energy contents, feed value and feed quality were determined, then the data were subjected to analysis of variance. The effects of urea and molasses additives added to the mixed forage plant silage on all parameters were found to be significant (P < 0.05, P < 0.01). The crude protein (CP) increased its application by UM7. Cell wall component (insoluble fibre in acid detergent (ADF) and neutral detergent insoluble fibre NDF) reduced its application by UM9. All these applications increased the FS. The addition of molasses increased the in vitro gas production, while the addition of urea decreased the production. True organic matter digestibility increased with the addition of molasses. As a result, it was concluded that UM9 application in silages would be appropriate for increasing feed value and feed quality, and the UM3 application in silage would be appropriate for improving true organic matter digestibility (TOMD).