1. A trial was conducted to study the effects of additional dietary fibre (DF), resulting from partial replacement of soybean meal (SBM) with high-fibre sunflower meal (SFM), on egg production and gastrointestinal tract (GIT) traits in laying hens. 2. A total of 480 Nick Chick white laying hens (21 weeks of age) were randomly assigned to three dietary treatments and fed for 24 weeks. The hens were fed either the control diet based on corn and SBM, which contained 30 g/kg crude fibre (CF) without SFM, or test diets containing 40 g more CF/kg from adding 47 g/kg SFM or 50 g more CF/kg from adding 97 g SFM/kg. Each dietary treatment was replicated eight times (20 hens per replicate). 3. Body weight (P < 0.05), egg production rate (P < 0.05), egg weight (P < 0.01) and egg mass (P < 0.01) linearly increased but feed conversion ratio linearly decreased (P < 0.01) with increasing SFM supplementation. Feed intake, cracked/broken egg ratios and shell less egg ratios were comparable amongst the groups. 4. The egg quality indices were not influenced by dietary treatments, except for the Haugh units, which decreased (linear, P < 0.01; quadratic P < 0.05) when SFM was added. 5. Digestive organ size was not affected by the dietary treatments, but caecum length increased in hens fed SFM (P < 0.05). Digesta pH in the ileum and caecum was reduced linearly (P < 0.01) with SFM supplementation. 6. Small intestine morphology traits improved with 47 g SFM/kg supplementation, whereas negative effects were observed with 97 g SFM/kg. 7. Productive performance of laying hens improved with 40 or 50 g/kg more CF in feed, mostly from SFM supplementation. It was concluded that this performance increase was attributed mostly to the increase in fat content, rather than DF level, when high-fibre SFM was included in layer diets.

1. A trial was conducted to study the effects of partial replacement of sunflower meal (SFM) for soybean meal (SBM) on growth performance and gastrointestinal tract traits (GIT) in pullets. 2. A total of 600 pullets (29 d of age) was randomly assigned to three dietary treatments and fed for 84 d. The birds were fed a practical diet with a low level of crude fibre (CF; LF) or test diets containing a medium or high level of CF (MF and HF) by partial (50% to 75%) replacement of SBM with SFM. Accordingly, the grower diets contained 29, 40 and 51 g CF/kg, which corresponded to 31, 45 and 59 g CF/kg in developer diets. Each dietary treatment was replicated 8 times (25 pullets per replicate). 3. Body weight did not differ significantly among treatments at d 29, 84 and 112 d but increased (P < 0.05) with SFM supplementation at d 54. From 29 to 112 d of age, daily feed and energy intake linearly increased (P < 0.01) with SFM supplementation, but body weight gain and feed conversion ratios were comparable amongst the groups. 4. Digestive organ size was not affected by the dietary treatments, but gizzard weight increased in pullets fed MF and HF diets (P < 0.01). Digesta pH in the gizzard, duodenum, jejunum and ileum were reduced linearly (P < 0.01) with SFM supplementation, while a quadratic response was observed for proventriculus pH (P < 0.05). 5. Small intestine morphology traits improved with a moderate level of CF intake, whereas no benefit was observed with a high level of CF consumption. 6. The results showed that use of SFM up to 140 g/kg can be recommended for pullets fed diets based on corn and soybean meal. However, smaller intestinal absorptive capacity with higher SFM supplementation may occur.

A total of 640 Lohmann LSL hens were randomly allotted to 4 dietary treatments arranged in 2 × 2 factorial with 2 feed particle sizes (fine and coarse) and 2 feed forms (mash and crumble). The 2 particle sizes were achieved by grinding whole corn and wheat in the hammer mill to pass through 4- and 8-mm sieves. The laying hen diet was isonutritive, and each diet was fed to 8 enriched cages of 20 hens from 21 to 52 wk of age. Screen size and feed form did not affect feed intake, egg production, egg weight, egg mass, and quality traits of the eggs, except for yolk color score, which decreased with crumbling of the feed. Feed conversion ratio was greater (P < 0.01) in hens fed the coarsely ground diet than in hens fed the finely ground diet. Crumbling the feed increased (P < 0.01) feed intake and feed conversion ratio compared to those after mashing. The relative weight of the liver and length of the small intestines were greater (P < 0.05) in hens fed crumble than in hens fed mash. Finely grinding cereals decreased (P < 0.01) the pancreas and gizzard weight compared to those after coarse grinding. The pH of digestive organs showed significant responses to feed form. Crumbling resulted in increased (P < 0.01) pancreatic activities of amylase, while lipase secretion was not affected by the manipulations in screen size and feed form. Ileal villus measurements (villus height, villus height/crypt depth ratio, villus surface area) were greater (P < 0.01) in hens fed crumble than in hens fed mash, whereas particle size had no effect. Total tract digestibility coefficients of crude ash and ether extracts were improved narrowing screen size from 8 to 4 mm. Data illustrated that grinding cereals to pass through a 4-mm screen could improve the efficiency of feed conversion. However, feeding crumbles provided no benefit to productive performance and egg quality, although the absorptive capacity of laying hens increased.

The influence of the grinding and physical form of diets on growth performance, gastrointestinal tract (GIT) development and nutrient digestibility was studied in layer pullets from hatch to 112 d of age. Diet formed a 2 × 2 factorial with 2 hammer mill screen sizes to grind cereals (4 and 8 mm) and 2 forms (mash and crumble). A total of 864 1-day-old layer chickens were randomly assigned to 1 of the 4 treatment groups with 8 replicates (27 birds per replicate). Cumulatively, pullets fed crumbles consumed less feed (P < 0.05) and had better feed conversion ratio (FCR; P < 0.01) than those fed mash. Coarse grinding cereals (CG) improved FCR (P < 0.05) without significant change in cumulative feed consumption compared to that of fine grinding (FG). With regard to body weight gain (BWG), pullets benefited from crumbles from 1 to 56 d of age (P < 0.01). There were interactions (P < 0.05) between screen size and feed form in relation to FCR (1 to 28 d) and overall BWG. At 112 d of age, the relative weight (RW, g/100 g body weight) of the crop, gizzard, pancreas, and liver of crumble-fed birds were lower (P < 0.05) than those for birds fed mash. Pullets fed coarsely ground feed had higher RW of the crop, proventriculus, gizzard, liver, and caecum compared to those fed finely ground feed. Compared to mash feeding, pullets fed crumbles increased (P < 0.05) total tract digestibility of ether extract and crude protein and the activities of pancreatic amylase and lipase. Digestibility of ether extract (P < 0.05) and pancreatic amylase activity (P < 0.01) were higher in birds fed a CG diet than in birds fed the FG regimen. Regarding the nutrition of egg-laying pullets, crumbles might be preferred to mash feed when the main objective is to improve FCR. Data also suggested that cereals used for pullet feed can be ground more coarsely than is in current practice.

1. The aim of this study was to identify a feeding regimen that encourages good pasture use in slow (SG) and fast (FG) growing broiler genotypes under free-range management. 2. SG and FG birds fed on either an ad libitum (ADB) or a meal feeding (MEF) programme were given free outdoor access with or without fresh alfalfa from day 22 to 72 and from day 22 to 45, respectively. In two consecutive trials, 800 birds of each genotype were included in a factorial design using groups of 40 birds replicated 5 times. 3. Fresh alfalfa consumption did not improve growth performance and meat quality attributes, whereas the feeding regimen had significant implications. When compared with their ad libitum-fed counterparts, meal-fed birds showed a significantly lower body weight at a considerably lower feed consumption rate, leading to a more favourable feed conversion ratio (FCR) during the course of the experiment. 4. The MEF regimen with a strong feed limitation significantly increased crop and gizzard weight in both genotypes. In FG birds, water holding capacity, drip loss, cooking loss and pH 45 in the breast and thigh meat were adversely affected by MEF; however, feed restriction demonstrated benefits with significant decreases in muscle fat accumulation. In SG birds, decreases in protein and dry matter content of the breast and thigh muscle with meal feeding were conclusive. 5. In both genotypes, there was no treatment-related effect on meat yield, mineral composition of the meat or bone mechanical properties. 6. In conclusion, MEF, irrespective of alfalfa intake, may provide a viable method to decrease FCR; it may be able to contribute to the production of chickens with lean carcasses but it was not capable of improving overall meat quality.

1. The aim of the present study was to examine the effects of improving vitamin D status in broiler diets by supplementary 25-hydroxycholecalciferol (25OHD(3)), alone or in combination with calcium (Ca) and available phosphorus (aP), on live performance, sternum mineralisation and breast meat quality in broilers. 2. A total of 936 1-d-old Ross 308 broilers were used in the study. After gender determination at the hatchery, chicks from each sex were randomly distributed into three dietary treatments. The following dietary treatments were used in the experiment from hatch to 38 d: (1) A control diet formulated to meet all of the nutrient requirements of broiler chicks according to the management guide; (2) The control diet supplemented with 18.7-15.0 mu g/kg of 25OHD(3); and (3) The control diet supplemented with 18.7-15.0 mu g/kg of 25OHD(3) plus Ca + aP. 3. Improvement in vitamin D status by 25OHD(3) supplementation, alone or in combination with Ca and aP, had no effect on body weight and feed conversion ratio of broilers. 4. The serum 25OHD(3) concentration significantly increased with 25OHD(3) and 25OHD(3) plus Ca + aP supplementation (P < 0.05), whereas the ionised Ca and Mg concentrations remained unchanged. 5. Sternum absolute weight, ash content and the concentrations of Ca and P significantly increased (P < 0.01) with supplementation of 25OHD(3), alone or in combination with Ca + aP. 6. Supplemental 25OHD(3), alone or in combination with Ca + aP, slightly increased pH(24) (P = 0.05) and decreased (P < 0.01) squeezable water loss in breast meat, whereas it had no significant effect on lightness, yellowness and sarcoplasmic protein solubility. 7. In conclusion, the results suggested that enhancing vitamin D status by 25OHD(3) supplementation alone or in combination with Ca + aP may improve sternum structure and mineral accretion. Furthermore, supplemental 25OHD(3), even in a nutritionally complete diet, may offer an effective way to improve protein solubility in female broilers.

Essential oil of oregano ( OEO: ) has proven to be a potential candidate for controlling chicken coccidiosis. The aim of the current study is to determine whether OEO and an approved anticoccidial, monensin sodium ( MON: ), as in-feed supplements could create a synergism when combined at low dosages. Day-old broiler chickens were separated into six equal groups with six replicate pens of 36 birds. One of the groups was given a basal diet and served as the control ( CNT: ). The remaining groups received the basal diet supplemented with 100 mg/kg MON, 50 mg/kg MON, 24 mg/kg OEO, 12 mg/kg OEO, or 50 mg/kg MON + 12 mg/kg OEO. All of the chickens were challenged with field-type mixed Eimeria species at 12 d of age. Following the infection (i.e., d 13 to 42), the greatest growth gains and lowest feed conversion ratio values were recorded for the group of birds fed 100 mg/kg MON (P < 0.05), whereas results for the CNT treatment were inferior. Dietary OEO supplementations could not support growth to a level comparable with the MON (100 mg/kg). The MON programs were more efficacious in reducing fecal oocyst numbers compared to CNT and OEO treatments (P < 0.05). Serum malondialdehyde and nitric oxide concentrations were decreased (P < 0.01), whereas superoxide dismutase (P < 0.05) and total antioxidant status (P < 0.01) were increased in response to dietary medication with MON and OEO. All MON and OEO treatments conferred intestinal health benefits to chickens by improving their morphological development and enzymatic activities. The results suggest that OEO supported the intestinal absorptive capacity and antioxidant defense system during Eimeria infection; however, it displayed little direct activity on the reproductive capacity of Eimeria This might be the reason for inferior compensatory growth potential of OEO compared to that MON following the challenge. Combination MON with OEO was not considered to show promise for controlling chicken coccidiosis because of the lack of a synergistic or additive effect.

The aim of this study was to investigate the efficacy of feed-grade preparations of mannan oligosaccharides ( MOS: ) and oregano essential oil ( OEO: ) in forced molted or fully fed 82-week-old, laying hens. A 2 × 3 factorial experiment investigated the influence of molting vs. full feeding and dietary supplements [i.e., unsupplemented control, MOS (1 g/kg) diet, and OEO (24 mg/kg) diet] on production parameters, egg quality, serum stress indicators, blood constituents, tibial characteristics, liver antioxidant status, and cecal microflora composition. A total of 864 Single Comb White Leghorn hens were randomly assigned to 6 treatments, each with 6 replicates of 24 hens each, and studied for 25 wk. Hens were fed a molt diet containing of 50% alfalfa and 50% wheat bran ( AA+WB: ) for 12 d, then returned to the laying ration. Results indicate that molt vs. full feed impacted more on most variables measured than supplementation or supplement type. Significant (P < 0.01) interactions between molting and diet were observed for the egg production, egg weight, egg mass, and feed conversion ratio ( FCR: ). In fully fed hens, MOS supplementation improved (P < 0.01) the egg production, egg weight, and FCR, and an OEO addition significantly improved the egg production and FCR in forced molted hens. Molting improved egg quality despite the significant regression in ovary and oviduct weight (P < 0.01), though supplements showed no influence. The bone ash (P < 0.01) and mineral content (P < 0.05) of molted hens were significantly lower than those of fully fed counterparts; however, poor mineralization was not reflected in the bones' mechanical properties. No significant differences were observed among treatments for hematological characteristics. Both the MOS and particularly the OEO supplementation improved (P < 0.01) liver antioxidant status and mitigated the significant increase in cecal pathogenic bacteria after molt. Our results indicate that full feeding with an aa+wb diet is an effective non-feed-removal method for molted hens, the benefit of which can be improved with MOS and OEO supplementation.

The influence of feed form (mash, crumble and pellet) and screen size (5 mm and 8 mm) on laying performance, egg quality, digestive organ measurements and gizzard pH was examined in laying hens using a 3 x 2 factorial arrangement of treatments. Lohmann LSL-Classic white egg layers (n = 864) at 28 weeks of age were randomly divided into 6 dietary treatments, each with 6 replicates of 24 birds over the following 24 weeks period. Significant (P < 0.05) interactions between feed form and screen size were observed for egg mass output. Grinding ingredients through a screen size of 5 mm instead of 8 mm, as well as further processing of the feed mixture as mash and crumble increased egg mass, whereas a contrasting pattern was observed in the case of feeding on pellets. Egg production rate, egg weight, and cracked-broken egg rate were not affected by either particle size or form of the feed. Administering the diet in the form of pellet and crumble decreased feed intake of hens compared to mash (P < 0.01). The feed conversion ratio of hens fed on crumbled and pelleted diets was significantly lower (P < 0.01) than for those receiving a mash diet (P < 0.01). Egg quality characteristics were barely affected by either screen size or feed form. However, the consumption of feed in the crumbled and pelleted forms decreased the yolk colour score by 4% (P < 0.05). Screen size and feed form had no effects on the percentage weight of liver, gizzard, length of small intestine and gizzard pH. However, lowering screen size from 8 to 5 mm increased pancreas weight (P < 0.01). The overall results of this experiment suggest that feed form (mash vs. crumbles or pellets) had a greater effect on the FI and FCR of laying hens than dietary ingredient particle size, with the best efficiency of feed conversion being obtained from pellet-fed birds. The effect of particle size was pronounced for eggshell mineralisation and pancreatic functions.

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.