930 resultados para BILIARY TRACT


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Genome-wide association studies (GWAS) have successfully identified several genetic loci associated with inherited predisposition to primary biliary cirrhosis (PBC), the most common autoimmune disease of the liver. Pathway-based tests constitute a novel paradigm for GWAS analysis. By evaluating genetic variation across a biological pathway (gene set), these tests have the potential to determine the collective impact of variants with subtle effects that are individually too weak to be detected in traditional single variant GWAS analysis. To identify biological pathways associated with the risk of development of PBC, GWAS of PBC from Italy (449 cases and 940 controls) and Canada (530 cases and 398 controls) were independently analyzed. The linear combination test (LCT), a recently developed pathway-level statistical method was used for this analysis. For additional validation, pathways that were replicated at the P <0.05 level of significance in both GWAS on LCT analysis were also tested for association with PBC in each dataset using two complementary GWAS pathway approaches. The complementary approaches included a modification of the gene set enrichment analysis algorithm (i-GSEA4GWAS) and Fisher's exact test for pathway enrichment ratios. Twenty-five pathways were associated with PBC risk on LCT analysis in the Italian dataset at P<0.05, of which eight had an FDR<0.25. The top pathway in the Italian dataset was the TNF/stress related signaling pathway (p=7.38×10 -4, FDR=0.18). Twenty-six pathways were associated with PBC at the P<0.05 level using the LCT in the Canadian dataset with the regulation and function of ChREBP in liver pathway (p=5.68×10-4, FDR=0.285) emerging as the most significant pathway. Two pathways, phosphatidylinositol signaling system (Italian: p=0.016, FDR=0.436; Canadian: p=0.034, FDR=0.693) and hedgehog signaling (Italian: p=0.044, FDR=0.636; Canadian: p=0.041, FDR=0.693), were replicated at LCT P<0.05 in both datasets. Statistically significant association of both pathways with PBC genetic susceptibility was confirmed in the Italian dataset on i-GSEA4GWAS. Results for the phosphatidylinositol signaling system were also significant in both datasets on applying Fisher's exact test for pathway enrichment ratios. This study identified a combination of known and novel pathway-level associations with PBC risk. If functionally validated, the findings may yield fresh insights into the etiology of this complex autoimmune disease with possible preventive and therapeutic application.^

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Left ventricular outflow tract (LVOT) defects are an important group of congenital heart defects (CHDs) because of their associated mortality and long-term complications. LVOT defects include aortic valve stenosis (AVS), coarctation of aorta (CoA), and hypoplastic left heart syndrome (HLHS). Despite their clinical significance, their etiology is not completely understood. Even though the individual component phenotypes (AVS, CoA, and HLHS) may have different etiologies, they are often "lumped" together in epidemiological studies. Though "lumping" of component phenotypes may improve the power to detect associations, it may also lead to ambiguous findings if these defects are etiologically distinct. This is due to potential for effect heterogeneity across component phenotypes. ^ This study had two aims: (1) to identify the association between various risk factors and both the component (i.e., split) and composite (i.e., lumped) LVOT phenotypes, and (2) to assess the effect heterogeneity of risk factors across component phenotypes of LVOT defects. ^ This study was a secondary data analysis. Primary data were obtained from the Texas Birth Defect Registry (TBDR). TBDR uses an active surveillance method to ascertain birth defects in Texas. All cases of non complex LVOT defects which met our inclusion criteria during the period of 2002–2008 were included in the study. The comparison groups included all unaffected live births for the same period (2002–2008). Data from vital statistics were used to evaluate associations. Statistical associations between selected risk factors and LVOT defects was determined by calculating crude and adjusted prevalence ratio using Poisson regression analysis. Effect heterogeneity was evaluated using polytomous logistic regression. ^ There were a total of 2,353 cases of LVOT defects among 2,730,035 live births during the study period. There were a total of 1,311 definite cases of non-complex LVOT defects for analysis after excluding "complex" cardiac cases and cases associated with syndromes (n=168). Among infant characteristics, males were at a significantly higher risk of developing LVOT defects compared to females. Among maternal characteristics, significant associations were seen with maternal age > 40 years (compared to maternal age 20–24 years) and maternal residence in Texas-Mexico border (compared to non-border residence). Among birth characteristics, significant associations were seen with preterm birth and small for gestation age LVOT defects. ^ When evaluating effect heterogeneity, the following variables had significantly different effects among the component LVOT defect phenotypes: infant sex, plurality, maternal age, maternal race/ethnicity, and Texas-Mexico border residence. ^ This study found significant associations between various demographic factors and LVOT defects. While many findings from this study were consistent with results from previous studies, we also identified new factors associated with LVOT defects. Additionally, this study was the first to assess effect heterogeneity across LVOT defect component phenotypes. These findings contribute to a growing body of literature on characteristics associated with LVOT defects. ^

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The effects of inclusion of pea hulls (PH) in the diet on growth performance, development of the gastrointestinal tract and nutrient retention were studied in broilers from 1 to 18d of age. There were a control diet based on low fibre ingredients (69.3 total dietary fibre (16.1g crude fibre/kg)) and three additional diets that resulted from the dilution of the basal diet with 25, 50 and 75g PH/kg (81.2, 93.2, and 105.1g total dietary fibre/kg diet, respectively). Each treatment was replicated six times and the experimental unit was a cage with 12 chicks. Growth performance, development of the gastrointestinal tract and the coefficients of total tract apparent retention (CTTAR) of nutrients were recorded at 6, 12 and 18d of age. In addition, jejunal morphology was measured at 12 and 18d and the coefficients of apparent ileal digestibility (CAID) of nutrients at 18d of age. Pea hulls inclusion affected all the parameters studied. The inclusion of 25 and 50g PH/kg diet improved growth performance as compared to the control diet. The relative weight (g/kg body weight) of proventriculus (P≤0.01), gizzard (P≤0.001) and ceca (P≤0.05) increased linearly as the level of PH in the diet increased. The inclusion of PH affected quadratically (P≤0.01) villus height:crypt depth ratio with the highest value shown at 25g PH/kg. In general, the CTTAR and CAID of nutrients increased linearly and quadratically (P≤0.05) with increasing levels of PH, showing maximum values with PH level between 25 and 50g/kg diet. We conclude that the size of the digestive organs increases with increasing levels of PH in the diet. In general, the best performance and nutrient digestibility values were observed with levels of PH within the range of 25 and 50g/kg. Therefore, young broilers have a requirement for a minimum amount of dietary fibre. When pea hulls are used as a source of fibre, the level of total dietary fibre required for optimal performance is within the range of 81.2–93.2g/kg diet (25.6–35.0g crude fibre/kg diet). An excess of total dietary fibre (above 93.2g/kg diet) might reduce nutrient digestibility and growth performance to values similar to those observed with the control diet.

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The influence of the main cereal and feed form of the diet on performance and digestive tract traits was studied in 576 brown-egg laying pullets from 1 to 120 d of age. From 1 to 45 d of age, 4 diets arranged factorially with 2 cereals (corn vs. wheat) and 2 feed forms (mash vs. pellets) were used. Each treatment was replicated 6 times (24 pullets per replicate). From 46 to 120 d of age, all diets were offered in mash form and the only difference among diets was the cereal used. Cumulatively, pullets fed the corn diets had higher BW gain (P < 0.05) but similar feed conversion ratio as pullets fed the wheat diets. From 1 to 45 d of age, pullets fed pellets consumed more feed (P < 0.001) and had higher BW gain (P < 0.001) than those fed mash. Most of the beneficial effects of pelleting on productive performance were still evident at 120 d of age. At 45 d of age, gizzard weight (g/kg of BW) was higher (P < 0.01) in pullets fed corn than in pullets fed wheat diets. Feeding pellets reduced the relative weight of the digestive tract and the gizzard (P < 0.001) as well as the length (cm/kg of BW) of the small intestine (P < 0.01) at both ages. The pH of gizzard contents at 120 d of age was not affected by cereal but was lower in pullets that were fed mash from 1 to 45 d of age (P < 0.01). We conclude that wheat can be used in substitution of corn in pullet diets with only a slight reduction in BW gain and that feeding pellets from 1 to 45 d of age increased BW gain and pH of the gizzard and reduced the relative weight of the gizzard and the length of the gastrointestinal tract at 120 d of age.

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El objetivo general de esta Tesis doctoral fue estudiar la influencia de diversos factores nutricionales sobre los parámetros productivos y el desarrollo del tracto digestivo de pollitas rubias destinadas a la producción de huevos comerciales. Para alcanzar este objetivo se realizaron tres experimentos donde se estudió el cereal principal, el tamaño de partícula del cereal y el nivel de energía y la presentación de los piensos. En el experimento 1 se estudió la influencia del cereal (piensos con enzimas) y la presentación del pienso sobre los parámetros productivos y las características del tracto digestivo en 576 pollitas rubias de 1 a 120 d de edad. De 1 a 45 d de la edad, se utilizaron 4 piensos experimentales organizados de forma factorial con 2 cereales al 50% de inclusión (maíz vs. trigo) y 2 presentaciones del pienso (harina vs. gránulo de 2- mm de diámetro). Cada tratamiento se replicó 6 veces (24 pollitas por réplica). De 46 a 120 d de edad todas las dietas (maíz o trigo) se ofrecieron en harina y por tanto, la única diferencia entre tratamientos fue el cereal utilizado. De 1 a 120 d de edad, las pollitas que recibieron los piensos basados en maíz tuvieron una ganancia de peso vivo (PV) superior (P < 0,05) que las que recibieron los piensos basados en trigo, pero el índice de conversión (IC) fue similar para ambos grupos. De 1 a 45 d de edad, las pollitas alimentadas con gránulo consumieron más pienso (P < 0,001) y tuvieron una ganancia de peso superior (P < 0,001) que las pollitas alimentadas con harina. Gran parte de los efectos beneficiosos de la granulación sobre los parámetros productivos se mantuvieron al final de la prueba (120 d de edad). A los 45 d de edad, el peso relativo de la molleja (PR; g/kg PV) fue superior (P < 0,01) en pollitas alimentadas con maíz que en pollitas alimentadas con trigo. La alimentación en gránulo redujo el PR del tracto gastro intestinal (TGI) y de la molleja (P < 0,001), así como la longitud relativa (LR; cm/kg PV) del intestino delgado (P< 0.01) a ambas edades (45 y 120 d de edad). El tipo de cereal utilizado no afectó al pH del contenido de la molleja a 120 d de edad pero fué inferior (P < 0,01) en las pollitas que recibieron el pienso en harina de 1 a 45 d de la edad que en las que recibieron el pienso en gránulo. Se concluye que el trigo puede substituir al maíz en piensos para pollitas si se acepta una ligera reducción en la ganancia de peso. Asímismo, la alimentación en gránulo de 1 a 45 d de edad aumentó la ganancia de peso a esta edad y al final de la prueba, así como el pH de la molleja a 120 d de edad. La presentación del pienso en gránulo redujo el PR de la molleja y la LR del TGI a 120 d de edad. En el experimento 2 se utilizaron un total de 864 pollitas rubias Hy-Line de 1 d de edad para estudiar la influencia del cereal de la dieta (500 g de maíz o trigo/kg) y el tamaño de partícula del mismo (molienda con molino de martillos con un diámetro de criba de 6, 8, o 10-mm) sobre los parámetros productivos y las características del TGI de 1 a 120 d de edad. Cada uno de los 6 tratamientos se replicó 6 veces (24 pollitas por réplica). De 1 a 45 d de edad, la ganancia de PV aumentó (P< 0,001) y el IC se mejoró (P < 0,05) al reducir el tamaño de partícula del cereal, pero no se observaron diferencias en el periodo crecimiento de 45 a 120 d de edad. A los 45 d de vida, las pollitas alimentadas con maíz tendieron (P < 0,10) a tener un mayor PR del TGI y del proventrículo y una mayor LR del intestino delgado que las pollitas alimentadas con trigo. Asímismo, el PR del TGI a esta edad, aumentó (P < 0,05) a medida que aumentaba el tamaño de partícula del cereal utilizado. A los 120 d de edad, el tratamiento no afectó el PR de ninguno de los órganos del TGI ni al pH de la molleja. Sin embargo, la LR del intestino delgado fue superior (P < 0,05) para las pollitas alimentadas con trigo que para las pollitas alimentadas con maíz. La LR del TGI se redujó (P < 0,05) al aumentar el tamaño de partícula del cereal. Se concluye que el trigo puede incluirse 500 g/kg en piensos de pollitas de 1 a 120 días de edad y que el tamaño de partícula de los cereales afecta el crecimiento de las pollitas durante los primeros 45 d de vida, pero no después. Por lo tanto, se recomienda moler el cereal utilizado al inicio del período de recría (1 a 45 d de edad) con una criba de diámetro igual o inferior a 8 mm. En el experimento 3 se utilizaron un total de 1.152 pollitas rubias Hy-Line de 1 d de edad para estudiar la influencia del nivel de energía de la dieta y la presentación del pienso sobre la productividad y las características del TGI. De 1 a 45 d de edad se utilizaron 6 piensos organizados de forma factorial con 3 concentraciones energéticas (baja: 11,44 MJ; media: 12,05 MJ y alta: 12,66 MJ/kg) y 2 presentaciones del pienso (harina vs. gránulo). De 45 a 120 d todos los piensos experimentales se suministraron en forma de harina y por tanto, la única diferencia entre tratamientos fue el nivel de EMAn utilizado. Cada uno de los 6 tratamientos se replicó 8 veces y la unidad experimental fue la jaula con 24 pollitas. De 1 a 120 d de edad, la ganancia de PV y el IC mejoraron a medida que aumentó la EMAn del pienso (P < 0,001). Las pollitas alimentadas con gránulo de 1 a 45 d de edad comieron mas y tuvieron una ganancia de peso superior (P < 0,001) que las alimentadas con harina. En el global de la prueba, la ganancia de PV fue mayor (P < 0,01) para las pollitas alimentadas con piensos en gránulo. A los 45 d de edad, el PR de todos los segmentos del TGI estudiados fue inferior para las pollitas alimentadas con piensos de alta energía que para las pollitas alimentadas con piensos de media o baja energía. A 120 d de edad, el PR de la molleja fue superior (P < 0,01) para las pollitas alimentadas con piensos de baja energía que con los otros piensos. Sin embargo, la LR del TGI no se vió afectada por el nivel de energía de los piensos. A los 45 d de edad, la alimentación con gránulo redujo el PR del proventrículo (P < 0,05), de la molleja (P < 0,001) y del TGI (P < 0.001), así como la LR del intestino delgado (P < 0,05) y de los ciegos (P < 0,001). A pesar de que las pollitas solo recibieron los piensos en gránulo durante los primeros 45 d de vida, la alimentación con gránulos redujo el PR de la molleja y del proventrículo a 120 d de edad. Se concluye que la alimentación con gránulos durante los primeros 45 d de vida mejora el consumo de pienso y el PV de las pollitas a 120 d de edad. Un aumento del nivel de energía de la dieta de 12,0 a 12,7 MJ/kg mejora los parámetros productivos de 1 a 120 d de edad pero reduce el tamaño del proventrículo y de la molleja. En base de estos resultados concluimos que maíz y trigo con enzimas pueden utilizarse indistintamente en piensos para pollitas de 1 a 120 d de edad con sólo una ligera disminución del PV final con trigo. La granulación y la reducción del tamaño de partícula del cereal del pienso de primera edad (1 a 45 d de vida) y el uso de piensos de alta densidad energética, mejoran los PV a 120 d de edad. Por lo tanto, es recomendable moler los cereales con cribas de no más de 8-mm de diámetro. También, la granulación del pienso y el uso de piensos de alta energía (pobres en fibra bruta) pueden reducir el desarrollo del TGI especialmente de la molleja, lo que puede perjudicar el consumo posterior de pienso durante el inicio del ciclo de puesta. ABSTRACT The general objective of this Thesis was to study the effect of different nutritional factors on productive performance and the development of the gastrointestinal tract (GIT) of commercial brown egg-laying pullets from 1 to 120 d of age. In this respect, the influence of type and particle size of the cereal, and feed form, and energy content of the die,t were studied in 3 experiments. In experiment 1, the influence of the main cereal and feed form of the diet on performance and GIT traits was studied in 576 brown-egg laying pullets from 1 to 120 d of age. From 1 to 45 d of age, 4 diets arranged factorially with 2 cereals (maize vs. wheat) and 2 feed forms (mash vs. pellets) were used. Each treatment was replicated 6 times (24 pullets per replicate). From 46 to 120 d of age, all diets were offered in mash form and therefore, the only difference among diets was the cereal used. Cumulatively, pullets fed the maize diets had higher body weight (BW) gain (P< 0.05) but similar feed conversion ratio (FCR) than pullets fed the wheat diets. From 1 to 45 d of age, pullets fed pellets consumed more feed (P < 0.001) and had higher BW gain (P < 0.001) than pullets fed mash. Most of the beneficial effects of pelleting on productive performance of the birds were still evident at 120 d of age. At 45 d of age, gizzard relative weight (RW; g/kg BW) was higher (P < 0.01) in pullets fed maize than in pullets fed wheat. Feeding pellets reduced the RW of the GIT and the gizzard (P < 0.001) as well as the relative length (RL; cm/kg BW) of the small intestine (SI, P < 0.01) at both ages. The pH of the gizzard contents at 120 d of age was not affected by the main cereal of the diet, but was lower in pullets fed mash from 1 to 45 d of age (P < 0.01) than in pullets fed pellets. We conclude that wheat supplemented with enzymes can be used in substitution of maize in pullet diets with only a slight reduction in BW gain at 120 d of age. Also, feeding pellets from 1 to 45 d of age increased BW gain and pH of the gizzard, and reduced the RW of the gizzard and the RL of the GIT at 120 d of age. In experiment 2, a total of 864 brown-egg laying pullets was used to study the effects of the main cereal of the diet (500 g maize or wheat/kg) and particle size of the cereal (hammer milled to pass through a 6, 8, and 10-mm screen) on growth performance and GIT traits from 1 to 120 d of age. Each of the 6 treatments was replicated 6 times (24 pullets per replicate). Type of cereal did not affect pullet performance at any age. From 1 to 45 d of age, BW gain was increased (P < 0.001) and FCR was improved (P < 0.05) as the particle size of the cereal was reduced, but no effects were observed after this age. At 45 d of age, pullets fed maize tended (P < 0.10) to have a heavier RW of the GIT and proventriculus and a higher relative length (RL, cm/kg BW) of the SI than pullets fed wheat. Also at this age, the RW of the GIT increased (P < 0.05) with increases in particle size of the cereal. At 120 d of age, dietary treatment did not affect the RW of any of the organs studied or gizzard pH, but the RL of the SI was higher (P < 0.05) for pullets fed wheat than for pullets fed maize. Also, the RL of the SI was reduced (P < 0.05) as the particle size of the cereal increased. We conclude that 500 g wheat/kg can be included in pullet feeds from 1 to 120 d of age, and that particle size of the cereal affects pullet performance during the first 45 d of life but not thereafter. Therefore, it is recommended to grind the cereal used in this period with a screen size of no more than 8-mm. In experiment 3, a total of 1,152 one-day-old Hy-Line Brown egg laying pullets were used to study the influence of the energy content of the diet and feed form on productive performance and on several GIT traits. From 1 to 45 d of age, there were 6 diets arranged factorially with 3 concentrations of AMEn (low: 11.66 MJ/kg, medium: 12.05 MJ/kg and high: 12.66 MJ/kg) of the diet and 2 feed forms (mash vs. pellets). From 45 to 120 d all diets were fed in mash form and therefore, the only difference among treatments in this period was the energy content of the diets. Each of the 6 treatments was replicated 8 times and the experimental unit was formed by 24 pullets. Cumulatively, BW gain and FCR improved as the AMEn of the diet increased (P < 0.001). Also, pullets fed pellets from 1 to 45 d of age had higher feed intake and BW gain (P < 0.001) in this period and higher cumulative BW gain (P < 0.01) than pullets fed mash. At 45 d of age, the RWof all the segments of the GIT was lower for pullets fed the high- than for pullets fed the medium- or low- energy diets. At 120 d of age, the RW of the gizzard was higher (P < 0.01) for pullets fed the low energy diets than for pullets fed the other diets. However, the RL of the GIT was not affected by the energy content of the diet. Feeding pellets reduced the RW of the proventriculus (P < 0.05), gizzard (P < 0.001), and GIT (P < 0.001), as well as the RL of the small intestine (P < 0.05) and the ceaca (P < 0.001) at 45 d of age. The effects of feeding pellets on RW of gizzard and proventriculus were still evident at 120 d of age. We concluded that feeding pellets from 1 to 45 d of age improved feed intake and BW of pullets at 120 d of age and that an increase in the energy content of the diet increased pullet performance at all ages but reduced the RW of the proventriculus and gizzard. We conclude that maize and wheat can be used indistinctly in diets for egg laying pullets from 1 to 120 d of age, with only a slight reduction in final BW when wheat is used. Also, particle size of the cereal affects pullet performance during the first 45 d of life but not thereafter. Pelleting of the feeds, and grinding the cereal with a screen size of no more than 8-mm from 1 to 45 d of age, and the use of high density energy diets are recommended in order to achieve adequate target BW at 120 d of age. However, pelleting of the feed, very fine grinding, and the use of high AMEn diets might hinder the development of the GIT, especially that of the gizzard, which might affect feed intake of laying hens especially at the beginning of the production cycle.

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Automatic systems based on speech signal analysis for the early dete ction of obstructive sleep apnea (OSA) have achieved fairly high performance rates in recent years. However, a satisfactory explanation of these results has not been available. This presentation aims at explaining via an examination of the long-term spectra of OSA patients and normal control speakers these systems’ ability to discover OSA speakers on the base of all-purpose cepstral coefficients. An in terpretation of the long- term spectra in terms of the underlying tract settings suggests that the speech of OSA patients is characterized by a pharyngeal narrowing that may be captured by acoustic cues of the spectral contour of windowed speech frames. A novel interpretation of long-term spectra in terms of the first principal component of the temporal sequence of short-term amplitude-spectra is also discussed.

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Gender detection is a very important objective to improve efficiency in tasks as speech or speaker recognition, among others. Traditionally gender detection has been focused on fundamental frequency (f0) and cepstral features derived from voiced segments of speech. The methodology presented here consists in obtaining uncorrelated glottal and vocal tract components which are parameterized as mel-frequency coefficients. K-fold and cross-validation using QDA and GMM classifiers showed that better detection rates are reached when glottal source and vocal tract parameters are used in a gender-balanced database of running speech from 340 speakers.

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We investigated the effects of fiber inclusion in the diet on growth performance and digestive traits in pullets from hatching to 17 wk of age. The control diets of the 3 feeding periods (0 to 5 wk, 5 to 10 wk, and 10 to 17 wk) were based on corn and soybean meal and did not include any additional fiber source. The experimental diets included 2 or 4% of cereal straw or sugar beet pulp (SBP) at the expense (wt:wt) of the control diet. From 0 to 5 wk of age, fiber inclusion did not affect pullet performance. From hatch to 17 wk of age, the inclusion of straw had little effect on pullet performance but the inclusion of 4% SBP reduced (ADG) (P < 0.05) and reduced feed conversion ratio (FCR; P < 0.001). Pullets fed straw had greater ADG (P < 0.05) and better energy conversion ratio (P < 0.01) than pullets fed SBP. An increase in fiber from 2 to 4% reduced FCR (P < 0.05). Body weight uniformity was not affected by diet. Fiber inclusion increased the relative weight (% BW) of the gizzard at 5 wk (P = 0.056) and 10 wk (P < 0.01) of age, but no differences were detected between fiber sources. At same ages, the relative length (cm/kg BW) of the pullets (P = 0.058 and P < 0.01, respectively) and tarsus (P = 0.079 and P < 0.05, respectively) was higher in pullets fed SBP than in pullets fed straw. Fiber inclusion, however, did not affect any of these traits at 17 wk of age. In summary, the inclusion of 2% straw at the expense (wt:wt) of the whole diet did not affect pullet performance at 17 wk of age. An increase in the level of straw from 2 to 4% reduced FCR but did not affect ADG. The inclusion of SBP, however, reduced pullet growth, with effects being more pronounced at the higher level.

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The influence of feed form and energy concentration of the diet on growth performance and the development of the gastrointestinal tract (GIT) was studied in brown-egg laying pullets. Diets formed a 2 x 5 factorial with 2 feed forms (mash vs. crumbles) and 5 levels of energy differing in 50 kcal AMEn/kg. For the entire study (0 to 17 wk of age) feeding crumbles increased ADFI (52.9 vs. 49.7 g; P < 0.001) and ADG (12.7 vs. 11.6 g; P < 0.001) and improved feed conversion ratio (FCR; 4.18 vs. 4.27; P < 0.001). An increase in the energy content of the diet decreased ADFI linearly (P < 0.001) and improved FCR quadratically (P < 0.01) but energy intake (kcal AMEn/d) was not affected. BW uniformity was higher (P < 0.05) in pullets fed crumbles than in those fed mash but was not affected (P > 0.05) by energy content of the diet. At 5, 10, and 17 wk of age, the relative weight (RW, % BW) of the GIT and the gizzard, and gizzard digesta content were lower (P < 0.05 to P < 0.001) and gizzard pH was higher (P < 0.05 to P < 0.001) in pullets fed crumbles than in pullets fed mash. Energy concentration of the diet did not affect any of the GIT variables studied. In summary, feeding crumbles improved pullet performance and reduced the RW of the GIT and gizzard, and increased gizzard pH at all ages. An increase in the energy content of the diet improved FCR from 0 to 17 wk of age. The use of crumbles and the increase in the AMEn content of the diet might be used adventageously when the objetive is to increase the BW of the pullets. However, crumbles affected the development and weight of the organs of the GIT, which might have negative effects on feed intake and egg production at the beginning of the egg laying cycle.

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We hypothesize that pullets could respond similarly, independent of feed form, to the feeding of diets based on corn or wheat supplemented with adequate NSP enzymes. Also, pullets would quickly adapt their gastrointestinal tract and modify productive performance accordingly, when switched from crumbles to mash feeds. The aim of this research was to evaluate the effects of feeding crumbles for different periods of time, followed by feeding mash to 17 wk of age, on performance, gastrointestinal tract development, and body measurements of brown-egg laying pullets fed diets based on corn or wheat.

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Nerve growth factor (NGF) has been recently identified as an ovulation inductor factor (OIF) in the seminal plasma (SP) (Ratto et al. PNAS 2012; 109:15042-7). The presence of OIF in rabbit has been suggested but this protein has not yet been identified. Our aim was to study the mRNA expression in the rabbit male reproductive tract and to identify the protein β-NGF in the SP.

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This research studied the effects of additional fiber in the rearing phase diets on egg production, gastrointestinal tract (GIT) traits, and body measurements of brown egg-laying hens fed diets varying in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 10 treatments arranged as a 5 × 2 factorial with 5 rearing phase diets and 2 laying phase diets. During the rearing phase, treatments consisted of a control diet based on cereals and soybean meal and 4 additional diets with a combination of 2 fiber sources (cereal straw and sugar beet pulp, SBP) at 2 levels (2 and 4%). During the laying phase, diets differed in energy content (2,650 vs. 2,750 kcal AMEn/kg) but had the same amino acid content per unit of energy. The rearing diet did not affect any production trait except egg production that was lower in birds fed SBP than in birds fed straw (91.6 and 94.1%, respectively; P < 0.05). Laying hens fed the high energy diet had lower feed intake (P < 0.001), better feed conversion (P < 0.01), and greater BW gain (P < 0.05) than hens fed the low energy diet but egg production and egg weight were not affected. At 46 wk of age, none of the GIT traits was affected by previous dietary treatment. At this age, hen BW was positively related with body length (r = 0.500; P < 0.01), tarsus length (r = 0.758; P < 0.001), and body mass index (r = 0.762; P < 0.001) but no effects of type of diet on these traits were detected. In summary, the inclusion of up to 4% of a fiber source in the rearing diets did not affect GIT development of the hens but SBP reduced egg production. An increase in the energy content of the laying phase diet reduced ADFI and improved feed efficiency but did not affect any of the other traits studied.

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Members of the Eph family of tyrosine kinase receptors have been implicated in the regulation of developmental processes and, in particular, axon guidance in the developing nervous system. The function of the EphA4 (Sek1) receptor was explored through creation of a null mutant mouse. Mice with a null mutation in the EphA4 gene are viable and fertile but have a gross motor dysfunction, which is evidenced by a loss of coordination of limb movement and a resultant hopping, kangaroo-like gait. Consistent with the observed phenotype, anatomical studies and anterograde tracing experiments reveal major disruptions of the corticospinal tract within the medulla and spinal cord in the null mutant animals. These results demonstrate a critical role for EphA4 in establishing the corticospinal projection.

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Synpolydactyly (SPD) is a dominantly inherited congenital limb malformation. Typical cases have 3/4 finger and 4/5 toe syndactyly, with a duplicated digit in the syndactylous web, but incomplete penetrance and variable expressivity are common. The condition has recently been shown to be caused by expansions of an imperfect trinucleotide repeat sequence encoding a 15-residue polyalanine tract in HOXD13. We have studied 16 new and 4 previously published SPD families, with between 7 and 14 extra residues in the tract, to analyze the molecular basis for the observed variation in phenotype. Although there is no evidence of change in expansion size within families, even over six generations, there is a highly significant increase in the penetrance and severity of phenotype with increasing expansion size, affecting both hands (P = 0.012) and feet (P < 0.00005). Affected individuals from a family with a 14-alanine expansion, the largest so far reported, all have a strikingly similar and unusually severe limb phenotype, involving the first digits and distal carpals. Affected males from this family also have hypospadias, not previously described in SPD, but consistent with HOXD13 expression in the developing genital tubercle. The remarkable correlation between phenotype and expansion size suggests that expansion of the tract leads to a specific gain of function in the mutant HOXD13 protein, and has interesting implications for the role of polyalanine tracts in the control of transcription.

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The purine nucleoside inosine has been shown to induce axon outgrowth from primary neurons in culture through a direct intracellular mechanism. For this study, we investigated the effects of inosine in vivo by examining whether it would stimulate axon growth after a unilateral transection of the corticospinal tract. Inosine applied with a minipump to the rat sensorimotor cortex stimulated intact pyramidal cells to undergo extensive sprouting of their axons into the denervated spinal cord white matter and adjacent neuropil. Axon growth was visualized by anterograde tracing with biotinylated dextran amine and by immunohistochemistry with antibodies to GAP-43. Thus, inosine, a naturally occurring metabolite without known side effects, might help to restore essential circuitry after injury to the central nervous system.