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The aim of this study was to determine the localization and number of apoptotic cells in lung tissue and bronchus-associated lymphoid tissue (BALT) of newborns, young, and adult rats exposed to formaldehyde (6 ppm) or technical xylene (300 ppm) for 6 weeks (8 h/day). A total of 27 female Sprague-Dawley rats were used. Apoptotic cells were mainly localized around the bronchus and bronchioles and relatively less frequently on the walls of alveoli and interalveolar septa both in control and experimental groups. In the BALT, reactive cells were localized in the area under the epithelium and distributed homogenously within the lymphoid follicles. The numbers of apoptotic cells in the lung tissue including the BALT were significantly higher in young and adult rats exposed to formaldehyde and xylene than those detected in control groups. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 × 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

1. Two experiments were designed to determine the effect of dietary boron (B) in broiler chickens. In Experiment 1, a 2 × 4 factorial arrangement of treatments was used to investigate the effect of dietary calcium (Ca) and available phosphorus (aP) (adequate or deficient) and supplemental B (0, 20, 40, and 60 mg/kg diet). In Experiment 2, B, at 20 mg/kg, and phytase (PHY) (500 FTU/kg diet) were incorporated into a basal diet deficient in Ca and aP, either alone or in combination. 2. The parameters that were measured were growth performance indices, serum biochemical activity as well as ash and mineral (i.e. Ca, P, Mg, Fe, Cu and Zn) content of tibia, breast muscle and liver. 3. Results indicated that both supplemental B and dietary Ca and aP had marginal effects on performance indices of chickens grown for 42 d. 4. There were positive correlations (linear effect) between B concentrations of serum, bone, breast muscle and liver and the amount of B consumed. 5. Serum T3and T4activities increased linearly with higher B supplementation. 6. Increasing supplemental B had significant implications on breast muscle and liver mineral composition. Lowering dietary Ca and aP level increased Cu content in liver and both Fe and Zn retention in breast muscle. Tibia ash content and mineral composition did not respond to dietary modifications with either Ca–aP or B. 7. The results also suggested that dietary contents of Ca and aP do not affect the response to B regarding tissue mineral profile. Dietary combination with B and PHY did not create a synergism with regard to growth performance and bioavailability of the minerals. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to determine the immunohistochemical expression and localization of insulin-like growth factor-I (IGF-I), transforming growth factor-β2 (TGF-β2), basic fibroblast growth factor (bFGF) and epidermal growth factor-receptor (EGF-R) in developing rat ovaries. Eighteen female Wistar rats were enrolled in this study; newborn (n =6), one-month-old (n =6) and adult (n =6) rats. Formalin-fixed and parafin-embedded ovarian tissues were stained with antibodies against IGF-I, TGF-β2, bFGF and EGF-R, immunohistochemically. The ovarian cells were evaluated by semi-quantitative scoring system under light microscope. The staining of IGF-I, TGF-β2, bFGF and EGF-R were most intense in the oocytes and were heavily at one-month-old rats. A moderate immunostaining in theca cells and corpus luteii reacted with IGF-I in adult rats. Furthermore the staining intensity for IGF-I was moderate in granulosa cells of newborn rat ovaries. We detected also a moderate staining for TGF-β2 in corpus luteii of adult rats. In addition, we found a bFGF immunostaining mainly in oocytes of follicles of young and adult rats. Immunostaining for EGF-R was moderate in granulosa cells of one-month-old rats. In conclusion, this study suggests that growth factors play a pivotal role in ovarian function, especially in follicular development. The role of growth factor in controlling degeneration or growth (or both) of ovary follicles remain as explained. [Copyright &y& Elsevier]

Abstract: Bcl-2 and Bax proteins localised mainly in granulosa cells. Primordial and primary follicles of new born rat ovary showed an intensive nuclear staining for Bax but faint staining for Bcl-2. In terms of staining intensity, no remarkable difference was observed within the same stage of developing follicle. Compared to new born rats, granulosa cells of adult and one month old rat ovary showed an increased staining both for Bcl-2 and Bax proteins. No staining was observed in primordial follicles of one month old and adult rats. However, granulosa cells of primary follicles, granulosa cells and theca cells in tertiary follicles of adult rat ovary also showed a strong staining for Bcl-2 and Bax proteins. Oocytes of follicles from different developmental stages revealed an apparent staining both for Bcl-2 and Bax proteins. However, in the more mature follicles oocytes stained more intensively. In developing corpus luteum a remarkable staining was observed for Bax. However, the staining was more prominent in regressing corpus luteum. Contrary to this, Bcl-2 stained the luteal cells in developing corpus luteum strongly, while in the fully developed corpus luteum no staining for Bcl-2 was observed. In conclusion, there was an apparent relation between the expression of the apoptosis regulating protein Bcl-2 and Bax and follicular development. Thus, during the follicular development Bcl-2 and Bax may be involved in granulosa cell demise in rat ovary. Furthermore, increased levels of Bax and decreased levels of Bcl-2 in the fully developed corpus luteum suggest that Bax plays a role in apoptosis of luteal cells in rat ovary. [Copyright &y& Elsevier]