Establishing an essential amino acid profile for maintenance in poultry using deletion method.

This study aimed to estimate the essential amino acid profile and the ideal ratio for the maintenance of poultry by deletion method. A nitrogen balance (NB) trial was conducted using 198 adult roosters, housed individually in metabolic cages. The treatments were 33 purified diets being 11 diets with an amino acid mixture providing high protein intake of 500 mg N/BWkg (0.75) per day, 11 diets providing medium protein intake of 250 mg N/BWkg (0.75) per day (in each diet, one amino acid tested was diluted 50%) and 11 diets providing low protein intake of 125 mg N/BWkg (0.75) per day (made by omitting the amino acid tested). Each treatment had six replicates. After 48 h of fasting receiving water plus sucrose, the roosters were fed 40 g of the diets by tube once a day for 3 days. The excreta were collected within 72 h after the first feeding. The diets and excreta were analysed for nitrogen content. For each amino acid studied, a linear regression was fitted by NB and amino acid intake (AAI). The maintenance requirements were estimated as the AAI to maintain the NB equal to zero. The daily amino acid requirements for maintenance were estimated to be Lys 11, Met 29, Thr 23, Trp 5, Arg 50, Val 29, His 6, Gly 54, Phe 49, Leu 78 and Ile 21 mg/BWkg (0.75) per day. Therefore, the amino acid ratio for maintenance was concluded to be Lys 100, Met 276, Thr 220, Trp 48, Arg 467, Val 275, His 60, Gly 511, Phe 467, Leu 735 and Ile 198% independent of the scale. The essential amino acid profile and the ideal ratio for the maintenance of poultry estimated in this study contributed to improve the factorial model for estimating essential amino acid requirements for poultry.

Rate of feed passage in Japanese quail.

The rate of passage (ROP) in the gastrointestinal tract (GIT) influences the exposure time of food to the digestion and absorption processes. Consequently, ROP affects the efficiency of nutrient utilization and energy from the diet. This study aimed to determine the physiological parameters that characterize the digestive response, such as first appearance time (FAT), ROP, mean retention time (MRT) and transit time (TT) in adult Japanese quail (Coturnix coturnix japonica), and to evaluate the effects of sex, apparent metabolizable energy corrected for nitrogen balance (AMEn) content in the diet and different types of markers on these parameters. In the first trial, we investigated the effects of sex and AMEn level (high- and low-energy diet) on the FAT parameter. Thirty-two male and 32 female Japanese quail were randomly allocated to 8 battery cages and assigned to 4 treatments in a 2 × 2 factorial design with 4 replicates of 4 birds for each treatment. To determine the FAT, ferric oxide (1%) was added to the diet, and the excreta of the quail was monitored until the first appearance of the marker. The results indicated significant differences (P < 0.05) in the FAT between males (100 min) and females (56 min), regardless of the AMEn content. In the second trial, thirty-two 32-week-old female Japanese quail in the laying phase were assigned to four treatments in a 2 × 2 factorial design, in which the main independent variables were type of marker (Cr or Ti) and AMEn level (high- and low-energy diets). In order to determine ROP (ET1%), MRT and TT (ET100%), the markers (0.5%: Cr2O3 and 0.5%: TiO2) were added to the diets, and the excreta were collected for 750 min. The excretion times for 1% (ET1%), 25% (ET25%), 50% (ET50%), 75% (ET75%) and 100% (ET100%) were estimated using cumulative excretion curves. No effect was detected for the AMEn level (P > 0.05); however, the effect of different marker types was significant (P < 0.05). This difference increased with time and ET100% was estimated to occur at 59 min. The ROP was estimated to be 68 min. The TT was estimated to be 540 min using Cr and 599 min using Ti, with an average MRT value of 0930 h. Taken together, our findings support the hypothesis that Japanese quail digestion through the GIT can be dynamic and differ based on sex or marker type.

Stable isotopes to study sulfur amino acid utilization in broilers.

Nutritionists have been discussing whether the dietary supplementation of cyst(e)ine is required as a part of the dietary methionine (Met) in the total sulfur amino acid (TSAA) requirement to achieve optimum performance in broilers. Part of Met is converted to cysteine (Cys) to meet the Cys requirement, especially for feather growth. The TSAA requirement has been determined by using graded levels of free Met in the diet, without supplementation of free cyst(e)ine. It has also been argued that the Met to Cys ratio (Met : Cys) changes with age and even with different Met sources. The objective of this study was to evaluate the two sources of Met, while determining the proportion of Met and Cys in total dietary TSAA that optimize the performance of broilers. A performance assay was carried out in a factorial arrangement (5 × 2) using 1080 broilers from 42 to 56 days of age fed diets having different dietary proportions of Met and Cys (44 : 56, 46 : 54, 48 : 52, 50 : 50 or 52 : 48) while maintaining the same dietary TSAA in the diets. Two synthetic Met sources (dl-Met or l-Met) were used for each of the diets with different dietary Met : Cys ratios. Twenty-one broilers of the same age were fed the diets 44 : 56, 48 : 52 and 52 : 48 by supplementing the diet with L-(15N) Met or L-(15N2) Cystine to study the metabolism of TSAA. No differences were observed between Met sources for feed intake, BW gain and feed conversion ratio (FCR; P > 0.05); however, FCR was numerically improved at 50 : 50 Met : Cys. Regarding TSAA utilization, the conversion of Met to Cys increased with increase in Met : Cys ratios, but the concentration of Met intermediates decreased. Broiler chickens responded to different dietary proportions of sulfur amino acids by altering their sulfur amino acid metabolism, and diets containing 50 : 50 Met : Cys is recommended for broilers of age 42 to 56 days.

Preparation and characterization of activated carbon from rice bran.

A study on the preparation of rice bran-based activated carbon was conducted, with and without an acid treatment step prior the activation process. The influence of the activation time on the structure of the activated carbons was evaluated. The acid treatment had a significant positive influence on sorption properties. The rice bran-activated carbon presented a BET surface area of 652m(2)g(-1) and a pore volume of 0.137cm(3)g(-1), with mesopores predominance (ca. 55%). These experimental results indicated the potential use of rice bran as a precursor in the activated carbon preparation process, thus representing an economically promising material.

Immunolocalization of glutathione S-transferase in the rat uterus.

Immunohistochemical localization of glutathione S-transferase (GST) and enzyme cytochemical staining for endogenous peroxidase (Px) activity were studied in rat uteri. Both enzymes were clearly detected in the endometrium of the uterus taken from proestrus to estrus during the estrous cycle. Based on our data, the biological significance of GST in endometrium was discussed.

Detection of histidine decarboxylase (HDC) in paraffin sections of formalin fixed rat stomach using avidin-biotin-peroxidase-complex method.

Immunohistochemical localization of histidine decarboxylase (HDC) in rat stomach was studied. Formalin fixed, paraffin sections were prepared and immunohistochemical localization of HDC was performed by the avidin-biotin-peroxidase-complex method (ABC method). As a result, HDC was clearly detected in the basal portion of the oxyntic glands. The shape of many HDC-positive cells were flasklike. No reaction products were seen in chief cells or parietal cells. These findings are in agreement with the results reported by many workers. Therefore, ABC method of HDC is thought to be a useful technique for the detection of enterochromaffin-like cells using paraffin sections.

Germinação assimbiótica e desenvolvimento de Dendrobium nobile Lindl. sob efeito de reguladores vegetais no tratamento pré-germinativo / Asymbiotic germination and development of Dendrobium nobile Lindl. under the effect of plant growth regulators in pre-germinative treatment

O presente trabalho teve como objetivo estudar a influência dos reguladores vegetais BAP e GA3 como tratamentos pré-germinativos no processo de germinação e desenvolvimento inicial de plântulas de Dendrobium nobile, espécie importante pelas propriedades farmacológicas como anti-oxidante, vasodilatadora e até mesmo anti-cancerígena, além do valor ornamental. Os tratamentos pré-germinativos consistiram de BAP e GA3, separadamente, nas concentrações de 0,0; 1,0; 2,0 e 5,0 mg L-1. Após seis meses da semeadura in vitro e manutenção em câmara de germinação e de crescimento com temperatura e foto-período controlados (12 horas e 23ºC ± 2), foram avaliados os parâmetros número de sementes germinadas, porcentagem de germinação, massa fresca e altura das plântulas, diâmetro e número de pseudobulbos, número de folhas, número de raízes, e o comprimento da maior raiz. O delineamento experimental foi inteiramente casualizado. Todas as variáveis foram submetidas à análise de variância e de regressão, quando significativas. As sementes de D. nobile germinaram melhor na ausência de reguladores vegetais e os tratamentos com BAP ou GA3 na embebição das sementes pouco beneficiaram o desenvolvimento in vitro de D. nobile.

The present study aimed to investigate the influence of plant growth regulators BAP and GA3 as pre-germinative treatment in the process of germination and initial development of seedlings of Dendrobium nobile, a species important for its pharmacological properties like antioxidant, vasodilator and even anticancer, besides its ornamental value. Pre-germinative treatments consisted of BAP and GA3, separately, at the concentrations of 0.0; 1.0; 2.0 and 5.0 mg L-1. At six months after in vitro sowing and maintenance in a germination and growth chamber with controlled temperature and photoperiod (12 hours and 23ºC ± 2), the following parameters were evaluated: number of germinated seeds, percentage of germination, fresh mass and height of seedlings, number and diameter of pseudo-bulbs, number of leaves, number of roots, and length of the largest root. The experimental design was completely randomized. All variables underwent analysis of variance and regression analysis when significant. D. nobile seeds presented better germination in the absence of plant growth regulators and the treatments with BAP or GA3 in seed imbibition little benefited D. nobile in vitro development.

Soft lens extended wear affects epithelial barrier function.

OBJECTIVE: To explore the impact of eye closure and soft contact lens extended wear (SCLEW) on epithelial permeability to fluorescein (Pdc). DESIGN: A prospective cohort study. PARTICIPANTS: Thirty-one noncontact lens (CL) wearers participated. INTERVENTION: The effects of eye closure on Pdc were evaluated by comparing morning (AM) and afternoon (PM) measurements on non-CL subjects. The effects of SCLEW on Pdc were determined by measuring Pdc before beginning SCLEW and then after 2, 4, and 12 weeks of SCLEW. MAIN OUTCOME MEASURES: Pdc measured in the morning versus the afternoon and before versus after SCLEW was examined. RESULTS: Analyses of Pdc were done using the natural logarithm (ln). The mean +/- standard error (SE) ln(Pdc) measured in the AM versus PM on 16 non-CL wearers did not differ significantly (-2.56+/-0.16 vs. -2.69+/-0.15, respectively; P = 0.46). In contrast, the mean +/- SE ln(Pdc) in 15 subjects after 2 (-1.73+/-0.183, P < 0.001), 4 (- 1.59+/-0.188, P < 0.001), and 12 weeks (-1.99+/-0.206, P = 0.02) of SCLEW was substantially greater than that measured before lens wear (-2.42+/-0.159 ln(nm/sec)). Interestingly, the mean+/-SE ln(Pdc) measured in the afternoon on seven subjects after 13 weeks of SCLEW was similar to their average baseline ln(Pdc) (-2.62+/-0.27 vs. -2.52+/-0.243, respectively; P = 0.54). Further analysis showed that Pdc was highest in the morning and decreased approximately 12.5%/hour (P < 0.001) during the day. CONCLUSIONS: Sleeping without CLs does not appear to alter Pdc; however, 2 weeks of SCLEW caused a 99% increase in permeability without observable changes by slit-lamp examination. Increases in Pdc appear greatest in the morning after SCLEW and then decrease exponentially during the day. Whether changes in Pdc will predict CL-associated keratopathy needs further study.