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1.
J Dairy Sci ; 106(4): 2904-2918, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36797185

RESUMEN

To evaluate the effects of heat stress environmental conditioning and dietary supplementation with organic acid and pure botanicals (OA/PB) on growth in dairy calves, we enrolled 62 bull (noncastrated) and heifer calves in a study with a completely randomized design. Calves were assigned to 1 of 5 groups (n = 11 to 14/group): (1) thermoneutral conditions (TN-Con), (2) HS conditions (HS-Con), (3) thermoneutral conditions and pair-fed to match nutrient intake with HS-Con (TN-PF), (4) HS with low-dose OA/PB [75 mg/kg of body weight (BW); 25% citric acid, 16.7% sorbic acid, 1.7% thymol, 1.0% vanillin, and 55.6% triglyceride; HS-Low], or (5) HS with high-dose OA/PB (150 mg/kg of BW; HS-High). Supplements were delivered as a twice-daily bolus via the esophagus from wk 1 through 13 of life; all calves, including those on the control treatments, received an equivalent amount of triglyceride used for microencapsulation. Calves were raised in TN conditions from birth until weaning. After weaning, calves (62 ± 2 d; 91 ± 10.9 kg of BW) were transported to a new facility and remained in TN conditions [temperature-humidity index (THI): 60 to 69] for a 7-d covariate period. Thereafter, calves remained in TN or were moved to HS conditions (THI: diurnal change 75 to 83 during night and day, respectively) for 19 d. Clinical assessments were performed thrice daily, BW was recorded weekly, and blood was sampled on d 1, 2, 3, 8, 15, and 19. Upon experiment completion, calves from HS-Con and TN-Con were euthanized, and hot carcass and visceral organ weights were recorded. The mixed model included calf as a random effect; treatment, day, hour (when appropriate) as fixed effects, and the interactions of treatment × day and treatment × hour (when appropriate). Rectal and skin temperatures and respiration rates were greater in HS-Con than in TN-Con. During heat stress exposure, dry matter intake (DMI), average daily gain (ADG), and gain to feed (G:F) were lower in HS-Con relative to TN-Con. Comparing HS-Con and TN-PF, ADG and G:F were similar. Plasma fatty acid concentrations were elevated in TN-PF compared with HS-Con and TN-Con. Despite tendencies for increased aspartate aminotransferase, HS conditions did not overtly influence liver and inflammation markers. Liver weights were lower in HS-Con relative to TN-Con. During the first week of heat exposure, DMI was greater for HS-Low relative to HS-Con. Supplementation of OA/PB at low and high levels had a similar G:F to HS-Con. We conclude that reductions in DMI accounted for production losses during HS conditioning and that dietary OA/PB supplementation was not able to improve growth performance in heat-stressed calves.


Asunto(s)
Enfermedades de los Bovinos , Trastornos de Estrés por Calor , Animales , Bovinos , Femenino , Masculino , Alimentación Animal/análisis , Dieta/veterinaria , Suplementos Dietéticos , Ingestión de Alimentos , Trastornos de Estrés por Calor/veterinaria , Respuesta al Choque Térmico , Temperatura Cutánea
2.
J Dairy Sci ; 105(9): 7842-7860, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35931486

RESUMEN

To evaluate the effects of heat stress (HS) conditions and dietary organic acid and pure botanical (OA/PB) supplementation on gut permeability and milk production, we enrolled 46 multiparous Holstein cows [208 ± 4.65 dry matter intake (DMI; mean ± SD), 3.0 ± 0.42 lactation, 122 ± 4.92 d pregnant, and 39.2 ± 0.26 kg of milk yield] in a study with a completely randomized design. Cows were assigned to 1 of 4 groups: thermoneutral conditions (TN-Con, n = 12), HS conditions (HS-Con, n = 12), thermoneutral conditions pair-fed to HS-Con (TN-PF, n = 12), or HS supplemented with OA/PB [75 mg/kg of body weight (BW); 25% citric acid, 16.7% sorbic acid, 1.7% thymol, 1.0% vanillin, and 55.6% triglyceride; HS-OAPB, n = 10]. Supplements were delivered twice daily by top-dress; all cows not supplemented with OA/PB received an equivalent amount of the triglyceride used for microencapsulation of the OA/PB supplement as a top-dress. Cows were maintained in thermoneutrality [temperature-humidity index (THI) = 68] during a 7-d acclimation and covariate period. Thereafter, cows remained in thermoneutral conditions or were moved to HS conditions (THI: diurnal change 74 to 82) for 14 d. Cows were milked twice daily. Clinical assessments and BW were recorded, blood was sampled, and gastrointestinal permeability measurements were repeatedly evaluated. The mixed model included fixed effects of treatment, time, and their interaction. Rectal and skin temperatures and respiration rates were greater in HS-Con and HS-OAPB relative to TN-Con. Dry matter intake, water intake, and yields of energy-corrected milk (ECM), protein, and lactose were lower in HS-Con relative to HS-OAPB. Nitrogen efficiency was improved in HS-OAPB relative to HS-Con. Compared with TN-Con and TN-PF, milk yield and ECM were lower in HS-Con cows. Total-tract gastrointestinal permeability measured at d 3 of treatment was greater in HS-Con relative to TN-Con or TN-PF. Plasma total fatty acid concentrations were reduced, whereas insulin concentrations were increased in HS-Con relative to TN-PF. We conclude that exposure to a heat-stress environment increases total-tract gastrointestinal permeability. This study highlights important mechanisms that might account for milk production losses caused by heat stress, independent of changes in DMI. Our observations also suggest that dietary supplementation of OA/PB is a means to partly restore ECM production and improve nitrogen efficiency in dairy cattle experiencing heat stress.


Asunto(s)
Enfermedades de los Bovinos , Trastornos de Estrés por Calor , Animales , Peso Corporal , Bovinos , Enfermedades de los Bovinos/metabolismo , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Trastornos de Estrés por Calor/metabolismo , Trastornos de Estrés por Calor/veterinaria , Respuesta al Choque Térmico , Calor , Lactancia , Leche/metabolismo , Nitrógeno/metabolismo , Permeabilidad , Embarazo , Triglicéridos/metabolismo
3.
Nutr Res Rev ; 33(2): 218-234, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32100670

RESUMEN

In the current post-antibiotic era, botanicals represent one of the most employed nutritional strategies to sustain antibiotic-free and no-antibiotic-ever production. Botanicals can be classified either as plant extracts, meaning the direct products derived by extraction from the raw plant materials (essential oils (EO) and oleoresins (OR)), or as nature-identical compounds (NIC), such as the chemically synthesised counterparts of the pure bioactive compounds of EO/OR. In the literature, differences between the use of EO/OR or NIC are often unclear, so it is difficult to attribute certain effects to specific bioactive compounds. The aim of the present review was to provide an overview of the effects exerted by botanicals on the health status and growth performance of poultry and pigs, focusing attention on those studies where only NIC were employed or those where the composition of the EO/OR was defined. In particular, phenolic compounds (apigenin, quercetin, curcumin and resveratrol), organosulfur compounds (allicin), terpenes (eugenol, thymol, carvacrol, capsaicin and artemisinin) and aldehydes (cinnamaldehyde and vanillin) were considered. These molecules have different properties such as antimicrobial (including antibacterial, antifungal, antiviral and antiprotozoal), anti-inflammatory, antioxidant, immunomodulatory, as well as the improvement of intestinal morphology and integrity of the intestinal mucosa. The use of NIC allows us to properly combine pure compounds, according to the target to achieve. Thus, they represent a promising non-antibiotic tool to allow better intestinal health and a general health status, thereby leading to improved growth performance.


Asunto(s)
Alimentación Animal , Crianza de Animales Domésticos/métodos , Antiinfecciosos/farmacología , Estado de Salud , Extractos Vegetales/farmacología , Aves de Corral , Porcinos , Acroleína/análogos & derivados , Acroleína/farmacología , Animales , Antibacterianos , Benzaldehídos/farmacología , Suplementos Dietéticos , Disulfuros/farmacología , Intestinos/efectos de los fármacos , Magnoliopsida/química , Carne , Aceites Volátiles/química , Aceites Volátiles/farmacología , Fenoles/farmacología , Extractos Vegetales/biosíntesis , Extractos Vegetales/química , Aves de Corral/crecimiento & desarrollo , Aves de Corral/microbiología , Ácidos Sulfínicos/farmacología , Porcinos/crecimiento & desarrollo , Porcinos/microbiología , Terpenos/farmacología
4.
J Dairy Sci ; 102(2): 1224-1236, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30471914

RESUMEN

Co-supplementation of methyl donors may lower hepatic lipid content in transition cows. To define the ability of methyl donor supplementation (MDS) to reduce hepatic lipid content and modify the plasma lipidome, 30 multiparous Holstein cows (2.04 ± 0.69 lactations; 689 ± 58 kg of body weight; 3.48 ± 0.10 units of body condition score) were fed a ration with or without rumen-protected methyl donors (22 g/d of Met, 10 g/d of choline chloride, 3 g/d of betaine, 96 mg/d of riboflavin, and 1.4 mg/d of vitamin B12) from d -28 before expected calving through d 14 postpartum. Cows were randomly enrolled based on predefined selection criteria (body condition score and parity). Base diets without MDS were formulated for gestation (15.4% crude protein with a predicted Lys-to-Met ratio of 3.25; 1.44 Mcal of net energy for lactation/kg of dry matter) and lactation (16.6% crude protein with a predicted Lys-to-Met ratio of 3.36; 1.64 Mcal of net energy for lactation/kg of dry matter). Blood sampling occurred from d -28 relative to expected calving through d 14 postpartum. Liver tissue was biopsied at d -28 relative to expected calving and on d 5 and 14 postpartum. In addition to routine analyses, serum AA concentrations on d 10 and 12 were quantified using mass spectrometry. Plasma triacylglycerol (TAG) and cholesteryl esters (CE) were qualitatively measured using time-of-flight mass spectrometry. Data were analyzed using a mixed model with repeated measures. Dry matter intake and milk yield were not modified by MDS. The transition from d -28 relative to expected parturition to d 14 postpartum was characterized by increased plasma fatty acid (0.15 to 0.71 mmol/L) and ß-hydroxybutyrate (0.34 to 0.43 mmol/L) levels and liver lipid content (3.91 to 9.16%). Methyl donor supplementation increased the serum Met level by 26% and decreased the serum Lys-to-Met ratio by 21% on d 10 and 12, respectively. Moreover, the increase in hepatic lipid content from d 5 through 14 postpartum was suppressed with MDS relative to control (3.57 vs. -0.29%). Dietary MDS modified the TAG and CE lipidome. For example, MDS increased plasma TAG 46:3 (carbon number:double bond) by 116% relative to control cows on d 5 postpartum. Moreover, MDS tended to increase plasma CE 34:6. In contrast, MDS lowered plasma TAG 54:8 by 39% relative to control cows on d 5 postpartum. We concluded that in the absence of gains in dry matter intake and milk and milk protein yields, dietary MDS slows the progression of hepatic lipid accumulation and modifies the plasma TAG lipidome in transition cows.


Asunto(s)
Bovinos/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Metionina/metabolismo , Triglicéridos/sangre , Ácido 3-Hidroxibutírico/sangre , Animales , Betaína/metabolismo , Peso Corporal , Bovinos/crecimiento & desarrollo , Colina/metabolismo , Dieta/veterinaria , Suplementos Dietéticos/análisis , Femenino , Lactancia , Leche/química , Leche/metabolismo , Parto/metabolismo , Periodo Posparto/metabolismo , Embarazo , Riboflavina/metabolismo , Rumen/metabolismo
5.
J Dairy Sci ; 97(12): 7729-34, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25262189

RESUMEN

This study focused on changes in fibrous and protein fractions, changes in fiber digestibility and amount of indigestible neutral detergent fiber (NDF) as a consequence of increased maturity in alfalfa. A total area of 720 m(2) was divided in 18 blocks randomly assigned to 3 treatments, differing in cutting intervals. Treatment 1 was harvested with a 21-d cutting schedule, at a prebloom stage; treatment 2 with a 28-d schedule, at about first-bloom stage; whereas a full bloom was observed in treatment 3, harvested with a 35-d cutting schedule. Treatments were replicated 4 times through the spring-summer period for 2 subsequent years, 2011 and 2012. Statistical differences were observed for crude protein [treatment 1: 20.8%, treatment 2: 17.3%, and treatment 3: 17.0%; standard error of the mean (SEM)=0.83], soluble protein, and nonprotein nitrogen among treatments on a dry matter basis. Similar results were observed for acid detergent lignin (6.3, 6.9, and 7.3%, respectively; SEM=0.39), lower in treatment 1 compared with others, and in vitro NDF digestibility at 24 or 240 h. Indigestible NDF at 240 h resulted in lower values for treatment 1 compared with treatments 2 and 3 (15.5, 17.2, and 18.3%, respectively; SEM=1.54). Moreover, the indigestible NDF:acid detergent lignin ratio varied numerically but not statistically among treatments, being as much as 9% greater than the 2.4 fixed value applied for rate of digestion calculation and Cornell Net Carbohydrate Protein System (Cornell University, Ithaca, NY)-based model equations. Assuming the diet composition remained unchanged, treatment 3 (35-d cutting interval) would be expected to yield 1.4 kg less milk per day based on energy supply, and 2.8 kg less milk daily based on protein supply than treatment 1.


Asunto(s)
Alimentación Animal/análisis , Fibras de la Dieta/metabolismo , Proteínas en la Dieta/metabolismo , Digestión/fisiología , Medicago sativa/crecimiento & desarrollo , Animales , Bovinos , Dieta/veterinaria , Proteínas en la Dieta/análisis , Técnicas In Vitro , Lignina/metabolismo , Medicago sativa/metabolismo
6.
J Appl Microbiol ; 114(2): 308-17, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23110383

RESUMEN

AIM: In vitro and in vivo challenge studies were undertaken to develop an in-feed additive of microencapsulated propionic, sorbic acids and pure botanicals to control Campylobacter jejuni in broilers at slaughter age. METHODS AND RESULTS: Organic acids (OA) and pure botanicals were tested in vitro against Camp. jejuni, whereas in vivo, chickens were fed either a control diet, or increasing doses of the additive for 42 days (experiment 1); in the second experiment, chickens received the additive at 0.1 or 0.3% from day 0 to 21 or from day 22 to 42. The additive consistently reduced Camp. jejuni caecal counts at any given dose (exp. 1) or inclusion plan (exp. 2). Moreover, it was able to reduce the number of goblet cells and modify mucin glycoconjugates biosynthesis pattern. CONCLUSIONS: We developed an additive that was effective in reducing Camp. jejuni in slaughter-age chickens even at low doses (0.1%). That efficacy was the result of the synergistic action between OA and botanicals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a strategy to reduce Camp. jejuni in broilers and, as a consequence, to improve the safety of the food chain. Moreover, data suggest that a treatment limited to the last weeks before slaughter would allow to save on inclusion of the additive throughout the whole production cycle.


Asunto(s)
Alimentación Animal , Infecciones por Campylobacter/veterinaria , Campylobacter jejuni/efectos de los fármacos , Pollos/microbiología , Aditivos Alimentarios/farmacología , Enfermedades de las Aves de Corral/microbiología , Animales , Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/patología , Campylobacter jejuni/crecimiento & desarrollo , Campylobacter jejuni/aislamiento & purificación , Ciego/citología , Ciego/microbiología , Eugenol/farmacología , Mucosa Intestinal/patología , Enfermedades de las Aves de Corral/patología , Propionatos/farmacología , Ácido Sórbico/farmacología , Timol/farmacología
7.
J Environ Manage ; 122: 25-30, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23542228

RESUMEN

The present study aims to assess the evolution of different proto-horizons as embryonic soils built by pedotechnologies for the reclamation and management of derelict and damaged lands, such as abandoned quarries. The model proto-horizons were assembled by utilizing coarse limestone gravel or zeolitized Phlegraean Yellow Tuff (PYT) as mineral components and commercial compost-amendments or a phosphorite-poultry manure mixture as organic matrices for growth of a pasture-grass under controlled conditions. The evolution of the model proto-horizons was followed by an evaluation of the stability and modification of the organic matter (OM) with reference to plant development. The results suggest that the natural carbonatic substrate occurring in limestone quarries was unable to sustain significant plant growth, while the PYT was suitable and efficient as a pedogenic substrate because it supported plant growth and induced a conspicuous accumulation of OM due to root activity. In particular, OM, including humic and non-humic components, greatly increased in the PYT treatment with the phosphorite-poultry manure mixture showing a concurrent trend toward humification. Conversely, an overall tendency toward degradation of OM was detected in the PYT model proto-horizon treated with commercial compost. Feasibility estimates show that quarry restoration costs appear reasonable where environmental impacts are high.


Asunto(s)
Suelo/análisis , Sustancias Húmicas , Italia , Contaminantes del Suelo/análisis
8.
Phys Rev Lett ; 108(15): 156603, 2012 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-22587272

RESUMEN

We demonstrate optical orientation in Ge/SiGe quantum wells and study their spin properties. The ultrafast electron transfer from the center of the Brillouin zone to its edge allows us to achieve high spin polarizations and to resolve the spin dynamics of holes and electrons. The circular polarization degree of the direct gap photoluminescence exceeds the theoretical bulk limit, yielding ∼37% and ∼85% for transitions with heavy and light holes states, respectively. The spin lifetime of holes at the top of the valence band is estimated to be ∼0.5 ps and it is governed by transitions between light and heavy hole states. Electrons at the bottom of the conduction band, on the other hand, have a spin lifetime that exceeds 5 ns below 150 K. Theoretical analysis of the spin relaxation indicates that phonon-induced intervalley scattering dictates the spin lifetime of electrons.

9.
Infection ; 40(5): 493-500, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22576022

RESUMEN

PURPOSE: Prevalence surveys are mostly used in European countries for infection surveillance in long-term care facilities (LTCFs). The purpose of this paper is to document the prevalence of infections in LTCFs and to identify and discuss the potential sources of variation in the overall prevalence of infections. METHODS: Six repeated prevalence surveys were carried out over a period of 3 years in 11 LTCFs in the Emilia-Romagna region, involving a mean of 812 residents in each survey. In one facility, continuous surveillance was also conducted. McGeer's infection criteria were used. Observers undertook a 1-day training course and on-field training. RESULTS: The average prevalence of infected residents was 11.5/100 residents: respiratory tract infections were the most common (5.7/100 residents), followed by urinary tract infections (2.6%), skin infections (1.9%), and ocular infections (1.4%). In a multivariate model, the prevalence significantly varied by season (p < 0.001) and residents' case-mix index (CMI, p < 0.001). In individual homes, the case mix varied from 0.91 to 1.1 and the observed prevalence varied from 6.6 to 40.4%. One facility set up and maintained continuous surveillance: three clusters of lower respiratory tract infection were identified in 1.5 years by a temporal scan test. Cases belonging to one outbreak only were captured by the prevalence surveys conducted in the same periods. CONCLUSIONS: The prevalence of infections in LTCFs needs to be interpreted cautiously, given the effects of seasonality and case-mix variation. Repeated prevalence surveys may be a good start in individual facilities, but the identification of outbreaks requires a continuous surveillance system.


Asunto(s)
Infecciones/epidemiología , Cuidados a Largo Plazo/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Distribución de Chi-Cuadrado , Monitoreo Epidemiológico , Femenino , Humanos , Italia/epidemiología , Masculino , Oportunidad Relativa , Prevalencia
10.
Poult Sci ; 90(8): 1676-82, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21753203

RESUMEN

The reduction of Salmonella prevalence in broilers is a priority in European Union agricultural policies because treatment with antibiotics is forbidden by Regulation (EC) 2160/2003. Two trials were conducted to evaluate the efficacy of a microencapsulated blend of sorbic acid and nature-identical compounds (i.e., chemically synthesized botanicals; SAB) on the reduction of the cecal prevalence and contents of Salmonella enterica serovars Hadar and Enteritidis in experimentally infected chickens. In the first trial, 125 one-day-old Lohmann specific-pathogen-free chickens were assigned to one of the following treatments: negative control (not challenged and not treated), positive control (challenged and not treated), SAB0.3, SAB1, or SAB5 (challenged and treated with the microencapsulated blend included in the feed at 0.03, 0.1, or 0.5%, respectively). At 30 d of age, birds were infected with 10(6) cfu of Salmonella Hadar, and after 5, 10, or 20 d postinfection, 5, 10, and 10 birds per treatment, respectively, were killed and the cecal contents and liver and spleen samples were analyzed for Salmonella Hadar. In the second trial, 100 one-day-old Ross 708 chickens were assigned to 1 of 5 treatments: control (not treated), SAB0.3, SAB1, SAB2, or SAB5 (treated with the blend included in the feed at 0.03, 0.1, 0.2, or 0.5%, respectively). At 7 d of age, the birds were challenged with 10(5) cfu of Salmonella Enteritidis, and after 7, 14, or 24 d after challenge, 5, 5, and 10 birds per treatment, respectively, were killed and cecal contents were analyzed for Salmonella Enteritidis. Results showed that in the early stage of infection Salmonella prevalence was high in both studies, whereas at the end of the observation periods, the blends at 0.03, 0.1, and 0.5 in the challenge with Salmonella Hadar and at 0.2 and 0.5% in the challenge with Salmonella Enteritidis significantly reduced (by 2 log(10) cfu) the cecal content of Salmonella. This study showed that intestinal delivery of microencapsulated sorbic acid and nature-identical compounds can result in a 100-fold reduction of Salmonella at the intestinal level in broilers at slaughter age.


Asunto(s)
Productos Biológicos/uso terapéutico , Pollos , Enfermedades de las Aves de Corral/prevención & control , Salmonelosis Animal/microbiología , Salmonella/clasificación , Ácido Sórbico/uso terapéutico , Alimentación Animal , Animales , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Productos Biológicos/administración & dosificación , Dieta/veterinaria , Composición de Medicamentos , Femenino , Salmonelosis Animal/prevención & control , Ácido Sórbico/administración & dosificación
11.
Phys Rev Lett ; 104(17): 176803, 2010 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-20482126

RESUMEN

We predict theoretically and show experimentally the occurrence of quantum confinement in hydrogenated nanocrystalline silicon. We prove that only valence states (positively charged carriers) are confined effectively within the nanograins. The emission associated to confined states is verified by photoluminescence experiments on nanocrystalline samples with controlled grain size. According to the present study, we propose nanocrystalline silicon as a promising material for oxygen-free optoelectronics, silicon-based memories and photovoltaics.

12.
Poult Sci ; 88(10): 2152-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19762869

RESUMEN

The aim of this study was to investigate the efficacy of the anticlostridial pediocin A from Pediococcus pentosaceus FBB61 to contain negative effects associated to Clostridium proliferation in broilers, through 2 subsequent investigations. In the first study, 36 Ross 508 broilers were divided into 3 groups and fed for 21 d as follows: the control diet (CTR), the control diet supplemented with supernatant filtrate of a culture of P. pentosaceus FBB61-2 (Bac-, isogenic mutant nonproducing pediocin A), and the control diet supplemented with supernatant filtrate of a culture of P. pentosaceus FBB61 (Bac+) containing pediocin A. Birds were challenged with 10(6) cells of Clostridium perfringens. In the second study, 216 Ross 508 broilers were allocated in 18 pens and divided into 3 groups fed the same diet for 42 d: a control group (CTR), a group challenged with 10(8) cells of C. perfringens (CP), and a group challenged with 10(8) cells of C. perfringens and receiving the control diet supplemented with P. pentosaceus FBB61 and pediocin A (PA). Broiler BW, ADG, ADFI, and feed conversion rate were measured throughout the studies. At the end of both experiments, an appropriate number of birds was killed and analyzed for necrotic enteritis lesions and microbiological examinations. In the first study, on d 9, ADG and BW were 20% higher for Bac+ compared with CTR and Bac-; on d 14, ADG was higher for Bac+ (+23%, P<0.05), whereas BW was higher for Bac+ and Bac- compared with CTR (+23 and +14%, respectively; P<0.05). In the second study, on d 14, ADG and BW were higher for PA compared with CTR and CP (+15% on average; P<0.05), whereas between 15 and 42 d, there was only a tendency toward a higher ADG for PA when compared with the CP group (+4%, P=0.08). Diet supplementation with pediocin A improved broiler growth performance during the challenge with C. perfringens and tended to restore the ADG depletion during the 42-d period.


Asunto(s)
Bacteriocinas/farmacología , Pollos , Infecciones por Clostridium/veterinaria , Clostridium perfringens/inmunología , Enteritis/veterinaria , Enfermedades de las Aves de Corral/microbiología , Animales , Bacteriocinas/uso terapéutico , Peso Corporal/fisiología , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/inmunología , Infecciones por Clostridium/microbiología , Enteritis/tratamiento farmacológico , Enteritis/inmunología , Enteritis/microbiología , Heces/microbiología , Femenino , Íleon/microbiología , Masculino , Pruebas de Sensibilidad Microbiana/veterinaria , Pediocinas , Proyectos Piloto , Enfermedades de las Aves de Corral/tratamiento farmacológico , Enfermedades de las Aves de Corral/inmunología , Distribución Aleatoria
13.
Clin Microbiol Infect ; 23(5): 335.e1-335.e5, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28259548

RESUMEN

OBJECTIVE: This multicentre cross-sectional study aims to estimate the prevalence of five neglected tropical diseases (Chagas disease, filariasis, schistosomiasis, strongyloidiasis and toxocariasis) among immigrants accessing health care facilities in five Italian cities (Bologna, Brescia, Florence, Rome, Verona). METHODS: Individuals underwent a different set of serological tests, according to country of origin and presence of eosinophilia. Seropositive patients were treated and further followed up. RESULTS: A total of 930 adult immigrants were enrolled: 477 men (51.3%), 445 women (47.9%), eight transgender (0.8%); median age was 37.81 years (range 18-80 years). Most of them had come from the African continent (405/930, 43.5%), the rest from East Europe, South America and Asia, and 9.6% (89/930) were diagnosed with at least one of the infections under study. Seroprevalence of each specific infection varied from 3.9% (7/180) for Chagas disease to 9.7% (11/113) for toxocariasis. Seropositive people were more likely to be 35-40 years old and male, and to come from South East Asia, sub-Saharan Africa or South America. CONCLUSIONS: The results of our study confirm that neglected tropical diseases represent a substantial health problem among immigrants and highlight the need to address this emerging public health issue.


Asunto(s)
Emigrantes e Inmigrantes , Enfermedades Desatendidas/epidemiología , Enfermedades Parasitarias/epidemiología , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Anciano , Anciano de 80 o más Años , Asia/epidemiología , Estudios Transversales , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Enfermedades Desatendidas/diagnóstico , Enfermedades Desatendidas/parasitología , Enfermedades Parasitarias/diagnóstico , Salud Pública , Estudios Seroepidemiológicos , Factores Socioeconómicos , América del Sur/epidemiología , Adulto Joven
14.
Animal ; 9(11): 1760-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26189883

RESUMEN

The aim of this study was to compare low doses of microencapsulated v. pharmacological ZnO in the diet of piglets on growth performance, ileum health status and architecture. One hundred and forty-four piglets weaned at 28 days and divided in 36 pens (two males and two females per pen), received a basal diet (control, Zn at 50 mg/kg) or the basal diet with ZnO at 3000 mg/kg (pZnO), or with lipid microencapsulated ZnO at 150 or 400 mg/kg (mZnO-300 and mZnO-800, respectively). After 14 and 42 days, three pigs per sex per treatment were euthanized to collect the ileum mucosa for immunohistochemistry, histomorphology, inflammatory cytokines and tight junction components gene expression. Data were analyzed with one-way ANOVA. At 0 to 14 days, the pZnO and mZnO-800 groups had greater average daily gain compared with control (P<0.05). Gain to feed ratio (G:F) in the same time interval was higher in pZnO group compared with control thus resulting in higher BW (P<0.05). At day 14, ileum villi height in mZnO-800 pigs was 343 µm v. 309 and 317 µm in control and pZnO, respectively (P<0.01) and villi:crypts ratio (V:C), as well as cells positive to proliferating cell nuclear antigen (PCNA), were greater in all treated groups compared with control (P<0.01). In mZnO-800 group, interferon-γ mRNA was the lowest (P=0.02), and both pharmacological ZnO and mZnO reduced tumor necrosis factor-α protein level (P<0.0001). Compared with pZnO group, mZnO-800 increased occludin and zonula occludens-1 protein level (1.6-fold and 1.3-fold, respectively; P<0.001). At day 42, both groups receiving microencapsulated ZnO had 1.7 kg greater BW than control and did not differ from pZnO group (P=0.01); ileum villi height and V:C ratio were the greatest for pZnO compared with the other groups, whereas PCNA-positive cells were the most numerous in mZnO-800 group (P<0.001). In conclusion, pigs receiving low doses of microencapsulated ZnO had G:F comparable with those receiving pharmacological level of ZnO in the overall post-weaning phase. Moreover, in the first 2 weeks post-weaning, microencapsulated ZnO effect on inflammatory status and ileum structure and integrity was comparable with pharmacological ZnO.


Asunto(s)
Citocinas/metabolismo , Suplementos Dietéticos , Enfermedades de los Porcinos/tratamiento farmacológico , Óxido de Zinc/administración & dosificación , Animales , Dieta/veterinaria , Composición de Medicamentos/veterinaria , Femenino , Regulación de la Expresión Génica , Íleon/efectos de los fármacos , Íleon/inmunología , Inflamación/veterinaria , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inmunología , Masculino , Porcinos , Uniones Estrechas/metabolismo
15.
J Clin Virol ; 60(1): 63-6, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24631117

RESUMEN

Varicella zoster virus (VZV) typically causes a benign disease in childhood. However, VZV can lead to severe complication in immunocompromised patients, involving skin and nearly every organ system, with significant morbidity and mortality. VZV infection occurs more frequently in patients treated with steroids. Herein, we describe a case of rapidly fatal disseminated VZV infection with cutaneous and visceral involvement in an adult AIDS patient treated with steroids.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Herpes Zóster/diagnóstico , Herpesvirus Humano 3/aislamiento & purificación , Huésped Inmunocomprometido , Esteroides/efectos adversos , Esteroides/uso terapéutico , Adulto , Resultado Fatal , Herpes Zóster/patología , Humanos , Masculino , Piel/patología , Vísceras/patología
16.
J Anim Sci ; 91(9): 4226-34, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23893996

RESUMEN

Two studies were conducted to assess the effects of dietary protein and Lys reduction on growth performance, carcass quality, N excretion, and plasma N profile in growing-finishing pigs from 35 to 180 kg. The growing trial was conducted with 72 gilts and 72 barrows with 6 pens per treatment and 6 gilts or 6 barrows per pen. Four diets with the same DE and NE were compared: 1) control diet, 2) diet with protein content reduced by 3% units compared with the control diet and supplemented with Lys HCl to match the requirements according to the 2012 NRC (FLys), 3) diet similar to FLys for protein level but supplemented with only 50% of the Lys HCl provided with FLys (-50% FLys), and 4) diet similar to FLys and -50% Flys for protein level with microencapsulated Lys added to supply 20% of the Lys provided by FLys (-80% MLys). Pigs fed the FLys diet performed in a similar manner and showed similar carcass characteristics to the control pigs. Pigs fed the -50% FLys diet had the lightest BW (P < 0.01) as well as the lightest carcass (P = 0.02) and trimmed thigh (P = 0.04) weights. Pigs fed the -80% MLys diet showed growth performance and carcass characteristics similar to the control pigs. The N balance study was conducted with 8 barrows arranged in a double replicated 4 × 4 Latin square design. The control pigs had greater (P < 0.01) N intake and urinary and total N excretion compared with pigs fed the low-protein diets. The reduction of the dietary protein concentration by 3% units decreased total N excretion by an average of 24.5% and the greatest reduction of total N excretion was obtained by the -80% MLys diet (26.12%) compared with the control diet throughout the trial. No effect of dietary treatment was observed on the plasma concentrations of ammonia, urea, and total AA in the 80-kg pigs. Decreased plasma ammonia (P < 0.01) and urea (P = 0.03) concentrations were detected in the 120-kg pigs fed the low-protein diets. The 160-kg pigs fed the -80% MLys pigs had less total AA, indispensable AA in particular (P < 0.01), than pigs fed the other diets and decreased ammonia (P < 0.01) and urea (P = 0.05) concentrations than the control pigs. The results showed that the use of microencapsulated Lys, compared with both Lys HCl and dietary protein-bound Lys, can save CP and synthetic AA in diet formulation and can reduce N excretion in manure without adversely affecting the growth performance and carcass quality of heavy growing-finishing pigs.


Asunto(s)
Composición Corporal , Dieta con Restricción de Proteínas/veterinaria , Lisina/metabolismo , Carne/análisis , Nitrógeno/metabolismo , Sus scrofa/fisiología , Alimentación Animal/análisis , Crianza de Animales Domésticos , Animales , Peso Corporal , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Heces/química , Femenino , Lisina/administración & dosificación , Masculino , Nitrógeno/sangre , Nitrógeno/orina , Distribución Aleatoria , Sus scrofa/crecimiento & desarrollo
17.
Animal ; 7(12): 1944-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24016452

RESUMEN

The objective of this study was to compare the efficiency of transfer of selenium (Se) to plasma and milk from inorganic sodium selenite, either free or microencapsulated, and from selenized yeast in dairy cows. The study consisted of an in situ-nylon bags incubation, and in an in vivo experiment to compare the Se status of cows supplemented with either sodium selenite, microencapsulated sodium selenite, or Se yeast. Thirty dairy cows, divided in five groups, were fed the following diets: the control group (CTR) received a total mixed ration supplemented with sodium selenite in order to have 0.3 mg/kg DM of total Se; 0.3M and 0.5M groups received the same control diet supplemented with lipid microencapsulated sodium selenite to provide 0.3 and 0.5 mg/kg DM of total Se, respectively; 0.3Y and 0.5Y groups received selenized yeast to provide 0.3 and 0.5 mg/kg of total Se, respectively. Cows were fed the supplements for 56 days during which milk, blood, and fecal samples were collected weekly to conduct analysis of Se and glutathione peroxidase (GSH-px) activity. Se concentration in the nylon bags was assessed to 72%, 64%, and 40% of the initial value (time 0) after 4, 8, and 24 h of incubation, respectively. In vivo, cows supplemented with 0.3 mg/kg of microencapsulated Se had higher milk Se concentration compared to CTR. The increment was more pronounced at the highest inclusion rate (0.5 mg/kg, 0.5M group). GSH-px activity was not significantly affected by treatments. The results indicate that lipid microencapsulation has the potential to protect nutrients from complete rumen reduction and that Se from microencapsulated selenite is incorporated in milk more efficiently than the free form. Microencapsulated sodium selenite was shown to be comparable to Se-yeast in terms of availability and incorporation in milk when fed at 0.3 mg/kg DM, whereas the inclusion in the diet at 0.5 mg/kg DM resulted in higher plasma and milk concentrations than selenized yeast.


Asunto(s)
Bovinos/fisiología , Selenio/sangre , Selenito de Sodio/farmacología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos/sangre , Dieta/veterinaria , Suplementos Dietéticos , Composición de Medicamentos , Heces/química , Femenino , Leche/química , Selenio/química , Selenito de Sodio/química
19.
J Phys Condens Matter ; 24(10): 104017, 2012 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-22353556

RESUMEN

The emission dynamics in GaAs/AlGaAs coupled ring-disk (CRD) quantum structures fabricated on silicon substrates is presented. The CRD structures are self-assembled via droplet epitaxy, a growth technique which, due to its low thermal budget, is compatible with the monolithic integration of III-V devices on Si based electronic circuits. Continuous wave, time resolved photoluminescence and theoretical calculations in the effective mass approximations are presented for the assessment of the electronic and carrier properties of the CRDs. The CRDs show a fast carrier dynamics which is expected to be suitable for ultrafast optical switching applications integrated on silicon.

20.
J Infect ; 65(2): 165-72, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22522292

RESUMEN

OBJECTIVES: Following a Chikungunya (CHIKV) outbreak in Italy, a cohort study was conducted to describe the infection long-term clinical course and outcome. METHODS: Persons identified through active and passive surveillance as confirmed or possible CHIKV cases during the outbreak were enrolled and interviewed by trained public health nurses, between 4-5 and 12-13 months following the acute stage. Patients reporting persistent clinical symptoms were evaluated by rheumatologists. Serum samples were obtained and anti-CHIKV specific IgG and IgM immune responses detected. Only confirmed cases who completed the follow-up were analysed. RESULTS: Out of 250 patients, 66.5% still reported myalgia, asthenia or arthralgia (most frequent sign) after 12 months. Functional ability, measured by the ROAD index, was more impaired for lower extremities (3.75; Inter Quartile Range - IQR 4.4), and the activities of daily living (average 4.2; IQR 5). Variables independently associated with the presence of joint pain at 12-13 months were increasing age, and history of rheumatologic diseases). Elderly, females, and persons with history of rheumatologic diseases had higher anti-CHIKV IgG titres at 12-13 months. CONCLUSIONS: This study confirms, in an unselected population, that the long-lasting burden of CHIKV infection is significant.


Asunto(s)
Infecciones por Alphavirus/epidemiología , Infecciones por Alphavirus/patología , Brotes de Enfermedades , Actividades Cotidianas , Adolescente , Adulto , Anciano , Anticuerpos Antivirales/sangre , Artralgia/epidemiología , Fiebre Chikungunya , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lactante , Recién Nacido , Italia/epidemiología , Masculino , Persona de Mediana Edad , Dolor/epidemiología , Estudios Prospectivos , Factores de Tiempo , Adulto Joven
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