In total, 432 thirty-six-week-old laying hens were fed a basal diet supplemented with mannan-oligosaccharide (MOS) or an essential oil mixture (EOM) from 36 to 51 wk of age. Hens were divided into 3 equal groups replicated 6 times with 24 hens per replicate. No significant difference was observed among the dietary treatments in terms of performance indices. Different from the dietary manipulation, high environmental temperatures negatively influenced all of the laying performance traits except the feed conversion ratio in association with the diminished feed consumption. The MOS, and particularly the EOM, tended to alleviate the deleterious effect of heat stress on BW gain. Mortality was higher in MOS-fed hens than with other treatments. A supplementation diet with MOS or EOM provided increments in eggshell weight (P < 0.01). Relative albumen weight was significantly decreased (P < 0.05) in response to EOM or MOS supplementation; however, this was not the case in the yolk weight rate. The MOS decreased albumen height and Haugh unit (P < 0.05). High environmental temperatures hampered entire egg quality characteristics except for the eggshell breaking strength and egg yolk weight. These results indicated that heat stress adversely affected both productive performance and egg quality. As for the results of this study, neither MOS nor EOM was efficacious in improving efficiency of egg production and stimulating humoral immune response in laying hens reared under moderate and hot climatic conditions. However, the ameliorative effect exerted by MOS and EOM on eggshell characteristics is conclusive.

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This study aimed to investigate the association of the methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C polymorphisms with serum drug levels and toxicities after high-dose methotrexate (MTX) infusion. The study included 37 children with acute lymphoblastic leukemia or non-Hodgkin lymphoma. Serum MTX levels and toxicities of bone marrow, liver and kidney were analysed. Genotype analysis of the C677T and A1298C gene polymorphisms from genomic DNA of the subjects was performed by real-time PCR. Subjects with MTHFR polymorphism for C677T (CT, TT) had significantly higher MTX levels at 24 h (p = 0.009), and these genotypes did not seem to cause toxicity. Subjects with MTHFR polymorphism for A1298C (AC, CC) had significantly higher MTX levels at 48 h (p = 0.02), and had more grade III/IV anemia (p = 0.02), thrombocytopenia (p = 0.0001), elevated AST levels (p = 0.04) and frequent febrile neutropenic episodes (p = 0.004). The present study suggests that A1298C gene, but not C677T polymorphism is associated with MTX-related toxicity.

White (Lohmann LSL) and Brown (ATAK-S) laying hens, were reared under organic and conventional cage rearing systems, and the effects of the rearing system on performance parameters, egg production, egg characteristics, and immune response were investigated. For this purpose, a total of 832 laying hens of two commercial hybrids, i.e., 416 white (Lohmann LSL) and 416 Brown (ATAK-S) layers, were used. The experiment lasted between 23 and 70 wk of age. In this study, the white layers yielded more eggs as compared to the brown layers in both organic and conventional production systems. Egg weight exhibited a similar pattern to that of laying performance. However, the total hen-housed egg number for the white birds in the organic system was fewer than that of white birds in the conventional cage facility; conversely, a contradictory tendency was observed for the brown birds. Livability of the white layers in the organic system was remarkably lower (14%) than that of the brown line, whereas the white line survived better (3.42%) than their brown counterparts in conventional cages. The feed conversion ratio of the white hens was markedly inferior in the organic system as compared to that of the white hens in the conventional system, whereas relatively lower deterioration was reported in brown layers when reared in an organic system. The organic production system increased egg albumen height and the Haugh unit in eggs of the brown layers. The yolk color score of organic eggs was lower than that of conventional eggs for both brown and white hens. The egg yolk ratio of eggs from white layers was found to be higher in organic eggs as compared to those obtained in the conventional system. All organic eggs had heavier shells than those produced in the conventional system. Eggs from brown layers had more protein content than eggs from white layers. Neither housing systems nor genotype influenced egg yolk cholesterol concentration. When compared to conventional eggs, n-3 fatty acid content was lower in organic eggs, and the n-6:n-3 ratio was higher in organic eggs. In conclusion, two hen genotypes showed different responses in terms of performance and egg quality to two different rearing systems. A commercial white strain produced more eggs with higher egg quality as compared to a native brown strain. The brown strain was found to have adapted well to organic production conditions when survival and total egg number was taken into consideration.

The efficacies of 5 widely used dietary supplements were investigated on performance indices, fecal oocyst excretion, lesion score, and intestinal tract measurements in healthy and Eimeria spp.-infected birds by using a comparative model. This study included 2,400 sexed Ross 308 broiler chicks that were equally divided in 2 groups: the infected group, experimentally infected with oocysts of mixed Eimeria spp. at 14 d of age, and the healthy controls. The birds in both groups were further divided equally into 6 groups, of which one was fed a basal diet and served as control without treatment and the other 5 served as experimental treatments. These 5 groups were fed 5 diets containing preparations of 60 mg/kg of anticoccidial salinomycin (SAL), 1 g/kg of multienzyme (ENZ), 1 g/kg of probiotic (PRO), 1 g/kg of prebiotic (PRE), and 40 mg/kg of an herbal essential oil mixture (EOM). Body weight gain and feed conversion ratio (FCR) showed significant improvement in the infected animals, which indicates that dietary supplemental regimens with SAL, ENZ, PRO, and PRE initiated in 1-d-old chicks reduced adverse effects after challenge with coccidiosis; however, chicks that were administered EOM failed to show such improvement. Uninfected chickens showed significant improvement in FCR with supplements SAL, PRE, and EOM, which signifies significant (P < 0.01) infection by supplement interactions for BW gain and FCR. In the infected group, all of the supplements reduced the severity of coccidiosis lesions (P < 0.01) induced by mixed Eimeria spp. through the middle and lower regions of the small intestines, whereas supplementation with SAL or EOM alone was effective (P < 0.01) in reducing oocyst excretion compared with the control treatment. The data indicated that use of these subtherapeutically efficacious supplements (except EOM) in broiler production can lessen the depression in growth due to coccidial challenge.

The effects of some alternative feed additives for antibiotic growth promoters on performance and some slaughter characteristics were examined in broilers fed wheat-soya based basal starter and finisher diets. A total of 2160 one-day-old male broiler chicks were randomly allocated to six groups with six replicate pens per treatment. The treatments were the basal diet (Control), and the basal diet supplemented with an antibiotic growth promoter (AGP); a prebiotic, mannan oligosaccharide (Bio-Mos, MOS); an essential oil of oregano (Herb-Mos Oregano, HMO); a plant extract of hop (Herb-Mos Hops, HMH) or a mixture of Herb-Mos Oregano and Herb-Mos Hops (HMOH). There were significant effects of dietary treatments on body weight and feed conversion ratio in the 0-21 d period, and on body weight and feed consumption in the 0-42 d period. The addition of all experimental additives to the diet resulted in significantly higher body weights as compared to the control treatment at both 21 and 42 days of age. Feed intakes were significantly different between the treatments at 0-21 d and 22-42 d periods, but not during the 0-42 d period. However, during the 0-21 d period the broiler chickens that received diets supplemented with AGP, MOS, HMO, HMH and HMOH had significantly better feed conversion ratios than the control group, but this pattern was not sustained during the finisher period (22-42 d). Mortality rate, hot carcass yield and relative weights of the small intestines, pancreas, abdominal fat and bursa of fabricius were not affected by experimental treatments. The HMH supplementation increased relative liver weight. These results showed that AGP, MOS and herbal feed additive (HMO, HMH, HMOH) supplementation to a diet provided significant advantages on broiler growth performance through a 42-d growth period. However, the combined supplementation of HMO and HMH did not exert either synergistic or additive benefits on the live performance of the broilers. These results also proved that MOS, HMO, HMH and HMOH improved broiler live performance as well as an AGP in both the starter and through the grower period. Furthermore, outstanding advantages were evidenced for the HMH treatment in particular. Therefore, the MOS, HMO, HMH and HMOH performance enhancer feed additives of natural origin may be considered as potential substitutes for AGP in broiler diets.

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The role of dietary supplemental mannan oligosaccharide (MOS) and an essential oil blend (EOB) on performance of laying hens, and susceptibility of egg yolk and hen liver to lipid oxidation were examined. Four hundred and thirty-two 52-week old Lohmann laying hens were divided into three groups and fed a basal diet containing no antioxidant as control (CNT), basal diet plus 1 g/kg MOS and basal diet with 24 mg/kg EOB, for a 10-week experimental period. Supplementation of diet with MOS and EOB improved egg production rate and eggshell weight, but did not influence other performance or egg quality traits. MOS and EOB provided higher antioxidant activity in egg yolk than the control regimen at all storage time periods. EOB also retained the oxidative stability of liver by measuring malondialdehyde (MDA) levels. Liver antioxidant enzymes, including superoxide dismutase (SOD) and glutathion peroxidase (GSH-Px), were higher in birds fed the additives. MOS and EOB tended to increase serum glucose concentration (6.2% and 8.8%, respectively) while they slightly decreased triglycerides (11.0% and 4.8%, respectively) without affecting cholesterol level. Relative weight of pancreas and spleen were not affected by dietary treatments whereas diet supplemented with EOB significantly increased liver weight. The findings of this study suggest that EOB and MOS could act as free radical scavengers that enhance performance and also increase eggshell weight.