RESUMEN

Fluvial sediment analysis and water quality assessment are useful to identify anthropic and natural sources of pollution in rivers. Currently, there is a lack of information about water quality in the Pixquiac basin (Veracruz state, Mexico), and this scarcity of data prevents authorities to take adequate measures to protect water resources. The basin is a crucial territory for Xalapa, the capital city of Veracruz state, as it gets 39% of its drinkable water from it. This research analyzed 10 physicochemical parameters and 12 metal concentrations in various rivers and sources during two seasons. Dissolved metals presented average concentrations (µg/L): Al (456.25) > Fe (199.4) > Mn (16.86) > Ba (13.8) > Zn (7.6) > Cu (1.03) > Pb (0.27) > As (0.12) > Ni (0.118) (Cd, Cr and Hg undetectable). Metals in sediment recorded average concentrations (ppm): Fe (38575) > Al (38425) > Mn (460) > Ba (206.2) > Zn (65.1) > Cr (29.8) > Ni (20.9) > Cu (16.4) > Pb (4.8) > As (2.1) (Cd and Hg undetectable). During the rainy season, Water Quality Index (WAWQI) classified stations P17 and P18's water as "unsuitable for drinking" with values of 110.4 and 117.6. Enrichment factor (EF) recorded a "moderate enrichment" of Pb in sediment in P24. Pollution was mainly explained by wastewater discharges in rivers but also because of erosion and rainfall events. Statistical analysis presented strong relationships between trace and major metals which could explain a common natural origin for metals in water and sediment: rock lixiviation.

Asunto(s)

Agua Potable , Monitoreo del Ambiente , Sedimentos Geológicos , Contaminantes Químicos del Agua , Calidad del Agua , Abastecimiento de Agua , México , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Agua Potable/química , Ríos/química , Metales Pesados/análisis , Metales/análisis

RESUMEN

Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, self-modulation in the perpendicular plane, at frequencies close to the plasma electron frequency, and are reproducible. Development of hosing depends on misalignment direction, its growth on misalignment extent and on proton bunch charge. Results have the main characteristics of a theoretical model, are relevant to other plasma-based accelerators and represent the first characterization of hosing.

RESUMEN

A Mössbauer spectrometer was built and evaluated using an amplified piezoelectric actuator under feedback control for the Doppler velocity drive. The actuator was driven with a quadratic displacement waveform, giving a linear velocity profile. The optimization of the piezoelectric Doppler drive under feedback control was performed with measurements from a laser Doppler vibrometer. 57Fe Mössbauer spectra of α-iron in transmission geometry show minimal peak distortions. The performance of this piezoelectric Doppler drive makes Mössbauer spectrometry possible in applications requiring small size, mass, and low cost.

RESUMEN

Mesenteric panniculitis (MP) is an uncommon, benign, condition that involves the mesenteric root. It may be idiopathic, or be associated with an inflammatory or malignant neoplasm. AIM: To establish the frequency of MP in oncologic patients according to the type of cancer. METHOD: Images of PET/CT performed between January 2008 and December 2019 on recently diagnosed oncologic patients were reviewed searching for MP. MP was defined as increased density and volume of mesenteric root fat, associated with nodules and/or lymph nodes, with or without pseudocapsule. Patients who had received previous cancer treatment or those with synchronous or metachronous malignancies were excluded. RESULTS: The frequency of MP in the total oncologic population was 5,3 % (82/1539). Types of cancer frequently associated with MP were non-Hodgkin lymphoma at 15,9% (31/195) and prostate cancer at 11,9% (16/134), both significantly higher than the rest of the malignancies (p < 0,01). Hodgkin Lymphoma (0/59), carcinoma of the cervix (0/45), and endometrial cancer (0/44) did not show MP. CONCLUSION: MP is more frequently associated with some malignant neoplasms, such as non-Hodgkin lymphoma and prostate cancer, and rare in others. This must be considered when studying patients with MP detected incidentally.

Asunto(s)

Linfoma no Hodgkin , Paniculitis Peritoneal , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Humanos , Masculino , Paniculitis Peritoneal/diagnóstico por imagen , Paniculitis Peritoneal/patología , Linfoma no Hodgkin/patología , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/diagnóstico por imagen , Neoplasias de la Próstata/patología , Persona de Mediana Edad , Femenino , Anciano , Estudios Retrospectivos , Adulto , Estadificación de Neoplasias , Anciano de 80 o más Años , Chile/epidemiología

RESUMEN

Amphidynamic crystals, which possess crystallinity and support dynamic behaviours, are very well suited to the exploration of emergent phenomena that result from the coupling on the dynamic moieties. Here, dipolar rotors have been embedded in a crystalline metal-organic framework. The material consists of Zn(II) nodes and two types of ditopic bicyclo[2.2.2]octane-based linkers-one that coordinates to the Zn clusters through two 1,4-aza moieties, and a difluoro-functionalized derivative (the dipolar rotor) that coordinates through linked 1,4-dicarboxylate groups instead. Upon cooling, these linkers collectively order as a result of correlated dipole-dipole interactions. Variable-temperature, frequency-dependent dielectric measurements revealed a transition temperature Tc = 100 K, when a rapidly rotating, dipole-disordered, paraelectric phase transformed into an ordered, antiferroelectric one in which the dipole moments of the rotating linkers largely cancelled each other. Monte Carlo simulations on a two-dimensional rotary lattice showed a ground state with an Ising symmetry and the effects of dipole-lattice and dipole-dipole interactions.

RESUMEN

BACKGROUND: Umbilical cord (UC) abnormalities are related to neurological outcome and death; specific molecular factors that might be involved are, as yet, unknown; however, protein-coding genes insulin-like growth factor 2 (IGF2) and cyclin-dependent kinase inhibitor 1C (CDKN1C) have been identified as potential candidates. METHODS: An analytical observational study was carried out. Newborn UCs were collected, along with their clinical and morphological features. Immunohistochemical analysis was made on paraffin-embedded sections and quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed in fresh UC tissue for the assessment of gene expression. RESULTS: A total of 100 newborns were included. A significant association was found between long UC and prematurity [odds ratio (OR) 9] and long UC and respiratory distress (OR 4.04). Gestational diabetes (OR 8.55) and hypertensive disorders of pregnancy (HDP) (OR 4.71) were found to be related to short UCs. The frequency for abnormal UC length was higher than expected. UC length was positively correlated with maternal, newborn and placental weight. No statistical association was found between IGF2 and CDKN1C (p57) expression and UC length; however, there was a tendency for higher CDKN1C expression in short UCs, while, on the contrary, higher IGF2 expression for long UCs. CONCLUSION: UC length was observed to be associated with maternal and newborn complications. Protein expression, messenger RNA (mRNA) activity and the activity of said genes seem to be related to UC length.

Asunto(s)

Inhibidor p57 de las Quinasas Dependientes de la Ciclina/metabolismo , Enfermedades del Recién Nacido/patología , Factor II del Crecimiento Similar a la Insulina/metabolismo , Complicaciones del Embarazo/patología , Cordón Umbilical/patología , Adulto , Femenino , Humanos , Recién Nacido , Enfermedades del Recién Nacido/metabolismo , Masculino , Embarazo , Complicaciones del Embarazo/metabolismo , Cordón Umbilical/metabolismo

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disorder, caused by the selective death of dopaminergic neurons in the substantia nigra pars compacta. ß-caryophyllene (BCP) is a phytocannabinoid with several pharmacological properties, producing anti-inflammatory and antihypertensive effects. In addition, BCP protects dopaminergic neurons from neuronal death induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), yet it remains unclear if this effect is due to its antioxidant activity. To assess whether this is the case, the effect of BCP on the expression and activity of NAD(P)H quinone oxidoreductase (NQO1) was evaluated in mice after the administration of MPTP. Male C57BL/6 J mice were divided into four groups, the first of which received saline solution i.p. in equivalent volume and served as a control group. The second group received MPTP. The second group received MPTP hydrochloride (5 mg/kg, i.p.) daily for seven consecutive days. The third group received BCP (10 mg/kg) for seven days, administered orally and finally, the fourth group received MPTP as described above and BCP for 7 days from the fourth day of MPTP administration. The results showed that BCP inhibits oxidative stress-induced cell death of dopaminergic neurons exposed to MPTP at the same time as it enhances the expression and enzymatic activity of NQO1. Also, the BCP treatment ameliorated motor dysfunction and protected the dopaminergic cells of the SNpc from damage induced by MPTP. Hence, BCP appears to achieve at least some of its antioxidant effects by augmenting NQO1 activity, which protects cells from MPTP toxicity. Accordingly, this phytocannabinoid may represent a promising pharmacological option to safeguard dopaminergic neurons and prevent the progression of PD.

Asunto(s)

Antioxidantes/uso terapéutico , Intoxicación por MPTP/metabolismo , Intoxicación por MPTP/prevención & control , NAD(P)H Deshidrogenasa (Quinona)/biosíntesis , Sesquiterpenos Policíclicos/uso terapéutico , Animales , Antioxidantes/farmacología , Intoxicación por MPTP/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Porción Compacta de la Sustancia Negra/efectos de los fármacos , Porción Compacta de la Sustancia Negra/metabolismo , Porción Compacta de la Sustancia Negra/patología , Sesquiterpenos Policíclicos/farmacología , Distribución Aleatoria

RESUMEN

We studied the influence of particle size of the main cereal of the diet on preference behavior by laying hens. Diets formed a 2 × 5 factorial with 2 main cereals (corn vs. barley) and 5 grinding sizes of the cereal (4, 6, 8, 10, and 12 mm screen). Each treatment was replicated 5 times (10 hens each). After a fasting period of 8 h, hens received their respective experimental diets from 06.00 to 14.00 hours. The geometric mean diameter (GMD) and the geometric standard deviation of the residuals in the feeder were determined every 2 hours. In addition, CP, ash, and Ca contents of the feeds were determined at the start and at the end of the experimental period. The experimental design was completely randomized with data analyzed as repeated measures with particle size and cereal as main effects. The GMD of the original feeds increased with increases in screen size and was greater for the barley than for the corn diets. The difference in GMD between the original diets and the residuals measured at 2 h intervals decreased as the experiment progressed (P < 0.001 for the interaction). Crude protein, ash, and Ca concentrated in the coarse fraction of the original diets and of the uneaten feed, an effect more pronounced for the minerals. Independent of the coarseness of the feed sieve, ash and Ca contents were higher in the uneaten feed at 14.00 h than in the original diets. Hens showed a clear preference for coarse particles irrespective of the concentration of CP, ash, or Ca in the different fractions of the diets. Data showed that birds under-consumed Ca during the morning, a period in which the requirements for mineral deposition are low. In summary, hens showed a significant preference for coarser particles, an effect that was more evident when the cereals were ground coarse. Hens, however, did not show any preference for consuming those feed fractions with greater CP, ash, or Ca contents.

Asunto(s)

Alimentación Animal/análisis , Pollos/fisiología , Preferencias Alimentarias , Hordeum , Zea mays , Animales , Dieta/veterinaria , Femenino , Hordeum/química , Tamaño de la Partícula , Distribución Aleatoria , Zea mays/química

RESUMEN

Introducción. Dado el aumento dramático de diabetes en el mundo, el objetivo de esta investigación fue analizar los valores de la glucemia en una población universitaria de nuevo ingreso para sustentar estrategias de detección y manejo preventivo de prediabetes y diabetes. Métodos. Estudio observacional, analítico, transversal, no probabilístico. Se analizaron los valores de glucemia en ayunas de 367 estudiantes de nuevo ingreso en 2011, y 430 en 2016 al campus de Ciencias de la Salud de una universidad del sureste de México. Se aplicaron pruebas de tendencia central, comparaciones y proyecciones. Resultados. En la muestra de 2011 hubo prevalencia de 11 por ciento de mujeres y 12,4 por ciento de hombres con glucemia en valores de prediabetes. En la de 2016, hubo 30,3 por ciento de mujeres y 40 por ciento en prediabetes. Hubo diferencia de los promedios de glucemia entre ambas muestras de 5,4 mg/dL (0,3 mmol/L) en mujeres, t = - 4,582 (p = 0,0001) y 10,81 mg/dL (0,6 mmol/L) en hombres, t = - 6,428 (p = 0,0001). No se encontró correlación con masa corporal. Conclusiones. En la muestra de 2016 hubo incremento en la prevalencia de prediabetes y de adultos jóvenes en riesgo de desarrollar diabetes mellitus de tipo 2, por lo que es necesario desarrollar estrategias para mejorar el estilo de vida.(AU)

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Introduction. Given the dramatic increase of diabetes in the world, the aim of this research was to analyze the values of blood glucose in a university population again income to support strategies for detection and preventive management of pre-diabetes and diabetes. Methods. Study observational, analytical, transverse, non-probability. The blood glucose values were analyzed in fasting of 367 freshmen students from move income in 2011 and 430 in 2016 to the campus of Health Sciences from a University in the Southeast of Mexico. Testing central tendency, comparisons and projections were applied. Results. In the sample of 2011 there was prevalence of 11 percent of women and 12.4 percent of men with blood glucose values of pre-diabetes. In the 2016 there were 30.3 percent of women and 40 percent in pre-diabetes. There was a difference of blood glucose averages among both samples of 5.4 mg/dL (0.3 mmol/L) in women, t = - 4.582 (p = 0.0001) and 10.81 mg/dL (0.6 mmol/L) in males, t = - 6.428 (p = 0.0001). Correlation with body mass was not found. C Conclusions. In the sample of 2016 there was increase in the prevalence of pre-diabetes and young adults at risk of developing type 2 diabetes mellitus by what is needed to develop strategies to improve lifestyle.(AU)

Asunto(s)

Humanos , Masculino , Femenino , Adulto , Estado Prediabético , Estudiantes del Área de la Salud , Incidencia , Progresión de la Enfermedad , Diabetes Mellitus , Enfermedades no Transmisibles , México

RESUMEN

The influence of the screen size used to grind the main cereal of the diet on egg production, gastrointestinal tract (GIT) development, and body measurements was studied in hens from 17 to 49 wk of age. Diets formed a 2 × 5 factorial with 2 main cereals (corn vs. barley) and 5 screen sizes of the cereal (4, 6, 8, 10, and 12 mm). Each treatment was replicated 5 times. No interactions between main cereal and screen size were observed for any of the traits studied. Cereal type and screen size did not affect feed intake, egg production, BW gain, or quality traits of the eggs. Eggs tended to be larger (P = 0.092) in hens fed the barley diet than in hens fed the corn diet. Also, feed conversion ratio tended to increase (P = 0.081) when the cereal of the diet was ground with a 4-mm screen as compared with the average of the other diets. At 49 wk of age, the relative weight (% BW) of the GIT and gizzard was greater (P < 0.05) in hens fed barley than in hens fed corn. An increase in the screen size increased linearly the relative weight of the GIT (P = 0.089), gizzard (P < 0.01), and liver (P = 0.056). None of the other GIT traits or body measurements was affected by the main cereal or the screen size. In summary, barley can substitute up to 45% of the corn in diets for laying hens without any adverse effect on egg production. Therefore, the use of one or other cereal will depend on their relative cost. An increase in screen size improved gizzard development but had little effect on hen productivity. Within the range studied, the size of the screen used for grinding the cereal had little effect on hen productivity, although the use of a 4-mm screen might increase feed conversion ratio and gizzard development.

Asunto(s)

Pollos/fisiología , Dieta/veterinaria , Grano Comestible/química , Conducta Alimentaria , Tracto Gastrointestinal/crecimiento & desarrollo , Oviparidad/efectos de los fármacos , Reproducción/efectos de los fármacos , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Femenino , Tracto Gastrointestinal/efectos de los fármacos , Tamaño de la Partícula

RESUMEN

ErbB-2 amplification/overexpression accounts for an aggressive breast cancer (BC) subtype (ErbB-2-positive). Enhanced ErbB-2 expression was also found in gastric cancer (GC) and has been correlated with poor clinical outcome. The ErbB-2-targeted therapies trastuzumab (TZ), a monoclonal antibody, and lapatinib, a tyrosine kinase inhibitor, have proved highly beneficial. However, resistance to such therapies remains a major clinical challenge. We here revealed a novel mechanism underlying the antiproliferative effects of both agents in ErbB-2-positive BC and GC. TZ and lapatinib ability to block extracellular signal-regulated kinases 1/2 and phosphatidylinositol-3 kinase (PI3K)/AKT in sensitive cells inhibits c-Myc activation, which results in upregulation of miR-16. Forced expression of miR-16 inhibited in vitro proliferation in BC and GC cells, both sensitive and resistant to TZ and lapatinib, as well as in a preclinical BC model resistant to these agents. This reveals miR-16 role as tumor suppressor in ErbB-2-positive BC and GC. Using genome-wide expression studies and miRNA target prediction algorithms, we identified cyclin J and far upstream element-binding protein 1 (FUBP1) as novel miR-16 targets, which mediate miR-16 antiproliferative effects. Supporting the clinical relevance of our results, we found that high levels of miR-16 and low or null FUBP1 expression correlate with TZ response in ErbB-2-positive primary BCs. These findings highlight a potential role of miR-16 and FUBP1 as biomarkers of sensitivity to TZ therapy. Furthermore, we revealed miR-16 as an innovative therapeutic agent for TZ- and lapatinib-resistant ErbB-2-positive BC and GC.

Asunto(s)

Neoplasias de la Mama/genética , Ciclinas/genética , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , MicroARNs/genética , Quinazolinas/farmacología , Neoplasias Gástricas/genética , Trastuzumab/farmacología , Regiones no Traducidas 3' , Animales , Antineoplásicos/farmacología , Sitios de Unión , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/genética , Femenino , Genes Supresores de Tumor , Humanos , Lapatinib , Masculino , Ratones , Modelos Biológicos , Regiones Promotoras Genéticas , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-myc/metabolismo , Interferencia de ARN , Proteínas de Unión al ARN , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo

RESUMEN

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.

Asunto(s)

Pollos/fisiología , Fibras de la Dieta/farmacología , Oviposición/fisiología , Alimentación Animal , Animales , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Relación Dosis-Respuesta a Droga , Metabolismo Energético , Femenino , Oviposición/efectos de los fármacos

RESUMEN

Membrane overexpression of the receptor tyrosine kinase ErbB-2 (MErbB-2) accounts for a clinically aggressive breast cancer (BC) subtype (ErbB-2-positive) with increased incidence of metastases. We and others demonstrated that nuclear ErbB-2 (NErbB-2) also plays a key role in BC and is a poor prognostic factor in ErbB-2-positive tumors. The signal transducer and activator of transcription 3 (Stat3), another player in BC, has been recognized as a downstream mediator of MErbB-2 action in BC metastasis. Here, we revealed an unanticipated novel direction of the ErbB-2 and Stat3 interaction underlying BC metastasis. We found that Stat3 binds to its response elements (GAS) at the ErbB-2 promoter to upregulate ErbB-2 transcription in metastatic, ErbB-2-positive BC. We validated these results in several BC subtypes displaying metastatic and non-metastatic ability, highlighting Stat3 general role as upstream regulator of ErbB-2 expression in BC. Moreover, we showed that Stat3 co-opts NErbB-2 function by recruiting ErbB-2 as its coactivator at the GAS sites in the promoter of microRNA-21 (miR-21), a metastasis-promoting microRNA (miRNA). Using an ErbB-2 nuclear localization domain mutant and a constitutively activated ErbB-2 variant, we found that NErbB-2 role as a Stat3 coactivator and also its direct role as transcription factor upregulate miR-21 in BC. This reveals a novel function of NErbB-2 as a regulator of miRNAs expression. Increased levels of miR-21, in turn, downregulate the expression of the metastasis-suppressor protein programmed cell death 4 (PDCD4), a validated miR-21 target. Using an in vivo model of metastatic ErbB-2-postive BC, in which we silenced Stat3 and reconstituted ErbB-2 or miR-21 expression, we showed that both are downstream mediators of Stat3-driven metastasis. Supporting the clinical relevance of our results, we found an inverse correlation between ErbB-2/Stat3 nuclear co-expression and PDCD4 expression in ErbB-2-positive primary invasive BCs. Our findings identify Stat3 and NErbB-2 as novel therapeutic targets to inhibit ErbB-2-positive BC metastasis.

Asunto(s)

Proteínas Reguladoras de la Apoptosis/biosíntesis , Neoplasias de la Mama/genética , MicroARNs/biosíntesis , Proteínas de Unión al ARN/biosíntesis , Receptor ErbB-2/biosíntesis , Factor de Transcripción STAT3/genética , Adolescente , Adulto , Anciano , Proteínas Reguladoras de la Apoptosis/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Persona de Mediana Edad , Metástasis de la Neoplasia , Proteínas de Unión al ARN/genética , Receptor ErbB-2/genética , Transducción de Señal , Activación Transcripcional/genética , Transfección

RESUMEN

Two experiments were conducted to study the effects of inclusion of additional fiber in the Phase I diet on growth performance and nutrient digestibility in piglets reared under "optimal" or "poor" hygienic conditions. In both experiments, the design was completely randomized with a control diet that contained 2.2% crude fiber and 8 additional isonutritive diets that included 2.5 or 5.0% of sugar beet pulp (SBP), straw, oat hulls (OH), or wheat middlings (WHM). Preplanned polynomial contrasts were used to study the effects of 1) fiber inclusion (control diet vs. average of the 8 fiber-containing diets), 2) source of fiber, 3) level of fiber, and 4) interaction between source and level of fiber. In Exp. 1 (clean barn), fiber inclusion increased ( < 0.01) the incidence of postweaning diarrhea (PWD) and reduced ( < 0.05) feed efficiency and apparent total tract digestibility (ATTD) of all nutrients except that of CP, which was not affected. Piglet performance was not affected by source or level of dietary fiber. The ATTD of all nutrients decreased ( < 0.05) as the level of fiber increased and was lower in pigs fed straw or OH than in pigs fed SBP or WHM. The apparent ileal digestibility of GE and DM decreased ( < 0.05) with fiber inclusion, a reduction that was more pronounced ( < 0.05) with straw or SBP than with OH inclusion, with WHM inclusion being intermediate. Fiber inclusion did not affect villous height to crypt depth ratio of the ileum mucosa. The inclusion of 5% of a fiber source increased and counts in the cecum ( < 0.001) but the to ratio was not affected. In Exp. 2 (dirty barn), fiber inclusion did not affect piglet performance but tended to increase PWD ( = 0.07). Also, fiber inclusion reduced ( < 0.05) the ATTD of all dietary components except that of CP, which was not affected. Source and level of fiber did not affect ATTD of nutrients except for DM, which was greater for pigs fed SBP than for pigs fed straw ( < 0.05). In conclusion, in the current research, pigs reared under optimal hygienic conditions had lower incidence of PWD, better growth performance, and greater DM and GE digestibility than pigs reared under poor hygienic conditions. An excess of dietary fiber was more detrimental for all these traits in piglets reared under optimal hygienic conditions. The effects of the source and level of fiber on piglet performance was limited in the 2 experiments.

Asunto(s)

Alimentación Animal/análisis , Fibras de la Dieta/análisis , Digestión/fisiología , Vivienda para Animales/normas , Porcinos/crecimiento & desarrollo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Higiene , Porcinos/fisiología

RESUMEN

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.

Asunto(s)

Fenómenos Fisiológicos Nutricionales de los Animales , Pollos/fisiología , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Fibras de la Dieta/análisis , Femenino , Tracto Gastrointestinal/crecimiento & desarrollo

RESUMEN

The effects of the main cereal and feed form of the rearing phase diets on growth performance, gastrointestinal tract characteristics, and body traits were studied in brown-egg pullets from hatch to 17 wk of age. Eight dietary treatments that were a combination of 2 main cereals (corn vs. wheat) and 4 feeding programs were used. The feeding program consisted in feeding crumbles from 0 to 5, 0 to 10, or 0 to 17 wk of age followed by mash until 17 wk, or feeding mash continuously from 0 to 17 wk. Each treatment was replicated 9 times. From hatch to 17 wk of age, pullets fed corn had similar ADG but poorer feed conversion ratio (FCR; P < 0.001) than pullets fed wheat. Also, pullets fed crumbles continuously (0 to 17 wk) had greater ADG (12.3 vs. 11.5 g; P < 0.001) and better FCR (4.21 vs. 4.36; P < 0.001) than pullets feed mash continuously, with pullets that were changed at any age of the rearing period from crumbles to mash feeding showing intermediate results. At 17 wk of age, the relative weights (% BW) of the gastrointestinal tract and gizzard were greater in pullets fed corn than in pullets fed wheat (P < 0.01) but the relative length (cm/kg full BW) of the small intestine, body, and tarsus was not affected. Pullets fed crumbles continuously had lighter gizzards (P < 0.001), higher gizzard pH (P < 0.001), and were shorter (P < 0.01) than pullets fed mash continuously, with pullets fed the other 2 treatments being intermediate. In summary, wheat can be used in substitution of corn in pullet diets without any adverse effect on growth performance. Feeding crumbles improves pullet performance but hinders gizzard and gastrointestinal tract development. Growth performance, gastrointestinal tract, and body traits of the pullets re-adapt quickly to changes in feed form of the rearing diets.

Asunto(s)

Fenómenos Fisiológicos Nutricionales de los Animales , Pollos/fisiología , Dieta/veterinaria , Tracto Gastrointestinal/fisiología , Triticum/química , Zea mays/química , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Suplementos Dietéticos/análisis , Enzimas/metabolismo , Femenino , Tracto Gastrointestinal/crecimiento & desarrollo

RESUMEN

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.

Asunto(s)

Alimentación Animal/análisis , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Pollos/anatomía & histología , Digestión/fisiología , Ingestión de Energía/fisiología , Metabolismo Energético , Femenino , Tracto Gastrointestinal/crecimiento & desarrollo , Oviposición