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1.
Biota Neotrop. (Online, Ed. ingl.) ; 23(4): e20231520, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1527942

RESUMEN

Abstract It is repeatedly stressed the need to characterize the extant biodiversity in tropical ecosystems. However, inventory studies are still progressing slowly in dry ecosystems, leading to the underestimation of their true biodiversity and hindering conservation efforts. In this study, we present primary and secondary data, along with an updated list of amphibians and reptiles from two localities in the São Francisco-Gurguéia region in Piauí. Additionally, we compare the species composition between nine areas within the Caatinga, which were sampled using standardized methods over the past ten years, to examine broader spatial patterns of community composition. To survey reptiles and amphibians, we employed similar methods and sampling efforts in two areas within the Serra das Confusões National Park (SCNP) region. Our surveys recorded a total of 73 species of amphibians and reptiles, of which 24 are new distribution records for the SCNP region. Consequently, our findings increase the known herpetofauna in the region to 94 species. Despite their proximity, the two sites in the SCNP region exhibited only 42% similarity in species composition, and they differed significantly from other areas within the Caatinga. Furthermore, even the closer Caatinga areas presented differences in species composition, highlighting the necessity to evaluate biodiversity across the landscape and contribute to understanding biogeographic patterns.


Resumo É repetidamente enfatizada a necessidade de caracterizar a biodiversidade vivente em ecossistemas tropicais. No entanto, os estudos de inventário ainda estão progredindo lentamente em ecossistemas secos, levando à subestimação de sua verdadeira biodiversidade e dificultando os esforços de conservação. Neste estudo, apresentamos dados primários e secundários, juntamente com uma lista atualizada de anfíbios e répteis de duas localidades na região de São Francisco-Gurguéia, do Piauí. Além disso, comparamos a composição de espécies entre nove áreas dentro da Caatinga, que foram amostradas usando métodos padronizados nos últimos dez anos, para examinar padrões espaciais mais amplos de composição da comunidade. Para estudar répteis e anfíbios, utilizamos métodos e esforços de amostragem semelhantes em duas áreas na região do Parque Nacional da Serra das Confusões (PNSC). Nossos levantamentos registraram um total de 73 espécies de anfíbios e répteis, das quais 24 são novos registros de distribuição para a região do PNSC. Consequentemente, nossos resultados aumentam a herpetofauna conhecida na região para 94 espécies. Apesar da proximidade, os dois locais na região do PNSC exibiram apenas 42% de similaridade na composição de espécies e diferiram significativamente de outras áreas dentro da Caatinga. Mesmo áreas mais próximas da Caatinga apresentaram diferenças na composição de espécies, destacando a necessidade de avaliar a biodiversidade em toda a paisagem e contribuir para a compreensão de padrões biogeográficos.

3.
J Fish Biol ; 99(3): 905-920, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33959963

RESUMEN

This study describes two new endemic Hypostomus species from central Brazil, which were previously identified as genetically distinct lineages in a recent genomic study that recommended their testing and potential description based on morphological data. A machine learning classification procedure (random forest) was used to investigate morphological variation and identify putatively diagnostic characters for these candidate species and revealed that each is morphologically distinct. The new species Hypostomus cafuringa is characterized by small size, dark spots under a light background, deeper caudal peduncle and shorter first ray of the pectoral fin and base of the dorsal fin when compared to congeneric species from the region. H. cafuringa is known from the headwaters of the Maranhão River, upper Tocantins River basin, Distrito Federal, Brazil. The second new species, Hypostomus crulsi, is characterized by dark spots under a light background, absence of plates along the abdomen region, shorter first ray of the pelvic fin, shorter first ray of the pectoral fin and smaller body size. H. crulsi is known from the headwaters of the São Bartolomeu River, upper Paraná River basin, Distrito Federal, Brazil. The rapid conversion of natural habitats for agricultural development and the isolation of protected areas represent a serious threat to the continued existence of these two newly described endemic species, which warrant conservation assessment.


Asunto(s)
Bagres , Animales , Tamaño Corporal , Brasil , Bagres/genética , Ecosistema , Ríos
5.
Animal ; 13(1): 33-41, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29785889

RESUMEN

Recent researches have showed that probiotics promote bone health in humans and rodents. The objective of this study was to determine if probiotics have the similar effects in laying hens. Ninety-six 60-week-old White Leghorn hens were assigned to four-hen cages based on their BW. The cages were randomly assigned to 1 of 4 treatments: a layer diet mixed with a commercial probiotic product (containing Enterococcus faecium, Pediococcus acidilactici, Bifidobacterium animalis and Lactobacillus reuteri) at 0, 0.5, 1.0 or 2.0 g/kg feed (Control, 0.5×, 1.0× and 2.0×) for 7 weeks. Cecal Bifidobacterium spp. counts were higher in all probiotic groups (P0.05). In addition, the plasma concentrations of cytokines (interleukin-1ß, interleukin-6, interleukin-10, interferon-γ and tumor necrosis factor-α) and corticosterone as well as the levels of heterophil to lymphocyte ratio were similar between the 2.0× group and the control group (P>0.05). In line with these findings, no differences of cecal tonsil mRNA expressions of interleukin-1ß, interleukin-6 and lipopolysaccharide-induced tumor necrosis factor-α factor were detected between these two groups (P>0.05). These results suggest that immune cytokines and corticosterone may not involve in the probiotic-induced improvement of eggshell quality and bone mineralization in laying hens. In conclusion, the dietary probiotic supplementation altered cecal microbiota composition, resulting in reduced shell-less egg production and improved bone mineralization in laying hens; and the dietary dose of the probiotic up to 2.0× did not cause negative stress reactions in laying hens.


Asunto(s)
Alimentación Animal/análisis , Densidad Ósea/efectos de los fármacos , Pollos/metabolismo , Dieta/veterinaria , Probióticos/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bifidobacterium , Calcificación Fisiológica , Ciego/microbiología , Citocinas/metabolismo , Suplementos Dietéticos , Cáscara de Huevo , Femenino , Óvulo , Distribución Aleatoria
6.
Poult Sci ; 98(3): 1083-1089, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30476217

RESUMEN

The objective of this study was to determine the effects of a dietary synbiotic inclusion on broiler bone health under daily cyclic heat stress. A total of 360 Ross 708 broilers were randomly assigned to 1 of 3 dietary treatments (8 replicates per treatment): a regular diet (control) and the regular diet mixed with a commercial synbiotic product at 0.5 (0.5X) or 1.0 (1.0X) g/kg. The synbiotic contains a prebiotic (fructooligosaccharides) and a probiotic mixture of 4 microbial strains (Enterococcus faecium, Pediococcus acidilactici, Bifidobacterium animalis, and Lactobacillus reuteri). Room temperature was gradually decreased from 34°C on d 1 by 0.5°C/d for the first 14 d; then a cyclic heat stress episode (32°C/9 h/d) was applied from d 15 to 42. Gait score assessment and the latency-to-lie test were conducted when broilers were 40 and 41 d of age, respectively. The tibia, femur, and humerus were collected for measuring bone parameters at 42 d of age. The data indicated that bone mineral density, bone mineral content, and bone area were higher and the level of gait score was lower in the 1.0X group (P = 0.05) but not in the 0.5X group (P > 0.05) compared to controls. The proportions of broilers showing signs of lameness were ranked 1.0X group (25%) < 0.5X group (45%) < control (54%). Compared to controls, broilers of 0.5X group stood longer (P = 0.03) during the latency-to-lie test. In conclusion, under the present conditions the synbiotic profoundly improves multiple indices of leg health of broilers subjected to the cyclic heat episodes, resulting in an improvement in walking ability.


Asunto(s)
Huesos/fisiología , Pollos , Dieta/veterinaria , Calor/efectos adversos , Cojera Animal/prevención & control , Enfermedades de las Aves de Corral/prevención & control , Simbióticos/administración & dosificación , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Huesos/efectos de los fármacos , Respuesta al Choque Térmico/efectos de los fármacos , Cojera Animal/etiología , Oligosacáridos/farmacología , Enfermedades de las Aves de Corral/etiología , Probióticos/farmacología , Distribución Aleatoria
7.
J Anim Sci ; 96(5): 1654-1666, 2018 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-29528406

RESUMEN

Probiotics reduce stress-related inflammation and abnormal behaviors in humans and rodents via regulation of the microbiota-gut-brain axis. The objective of this study was to determine if probiotic, Bacillus subtilis, has similar functions in broiler chickens under heat stress (HS). Two hundred forty 1-d-old broiler chicks were assigned to 48 pens with 4 treatments: Thermoneutral (TN)-RD (regular diet), TN-PD (the regular diet mixed with 1 × 106 CFU/g feed probiotic), HS-RD and HS-PD. Probiotic (Sporulin) was fed from day 1; and HS at 32°C for 10 h daily was initiated at day 15. The data showed that final BW, average daily gain , and feed conversion efficiency were improved in PD groups as compared to RD groups regardless of the ambient temperature (P < 0.01). Heterophil to lymphocyte ratio was affected by treatment and its value was in the order of HS-RD > HS-PD > TN-RD > TN-PD birds (P < 0.01). Compared to TN birds, HS birds spent more time in wing spreading, panting, squatting close to the ground, drinking, sleeping, dozing, and sitting but spent less time in eating, standing, and walking (P < 0.05 or 0.01). In addition, HS birds had greater levels of hepatic IL-6, IL-10, heat shock protein (HSP)70, and HSP70 mRNA expression (P < 0.01) and greater levels of cecal IgA and IgY (P < 0.01) compared to TN birds. Within TN groups, TN-PD birds had greater concentrations of hepatic IL-10 (P < 0.05) and cecal IgA (P < 0.01) than TN-RD birds. Within HS groups, HS-PD birds spent less time in wing spreading, panting, squatting close to the ground, drinking, sleeping, dozing, and sitting but spent more time in eating, foraging, standing, and walking than HS-RD birds (P < 0.05 or 0.01). The HS-PD birds also had lower concentrations of hepatic IL-6 and HSP70 (P < 0.01), whereas greater levels of IL-10 (P < 0.05) and lower concentrations of cecal IgA and IgY (P < 0.01). These results indicate that broilers fed the probiotic, B. subtilis, are able to cope with HS more effectively by ameliorating heat-induced behavioral and inflammatory reactions through regulation of microbiota-modulated immunity.


Asunto(s)
Alimentación Animal/análisis , Bacillus subtilis/fisiología , Pollos/fisiología , Suplementos Dietéticos , Respuesta al Choque Térmico/efectos de los fármacos , Probióticos/administración & dosificación , Animales , Ciego/inmunología , Pollos/inmunología , Pollos/microbiología , Dieta/veterinaria , Ingestión de Alimentos , Calor , Inflamación/veterinaria , Hígado/inmunología
8.
Poult Sci ; 96(6): 1524-1530, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28379573

RESUMEN

Ammonia (NH3) is a potential health hazard to both humans and animals, causing local and systemic low-grade inflammation based on its levels and exposure durations. The objective of this study was to examine the effects of 45 wk of exposure to 30 ppm NH3 on the concentrations of acute-phase proteins, immunoglobulins, and cytokines in laying hens. At 18 wk of age, a group of Hy-Line W-36 hens was randomly assigned to 4-hen cages. These cages were evenly divided between 2 environmentally controlled chambers. At 25 wk of age, one chamber was maintained continuously with fresh air (NH3 < 5 ppm; control group) and the other one was injected with NH3 and controlled at 30 ppm (NH3 group) for 45 wk. At 70 wk of age, blood and spleen samples (n = 8 per treatment) were collected for analyses of immunological parameters. No significant differences were observed in plasma levels of albumin, complement components (C)-3 and C-4, immunoglobulin (Ig)M, IgA and IgG, interleukin (IL)-6, IL-10, or interferon gamma in the NH3 group compared to control group. Compared to control hens, NH3 exposed hens had higher plasma levels of α-1-acid glycoprotein (24%) and tumor necrosis factor alpha (54%) and higher mRNA expression of IL-1ß (47%) and IL-6 (62.5%) in the spleen. These results indicated that hens may have the capability to adapt to chronic effects of moderate levels of NH3. Future studies should explore acute effects of NH3 at higher levels on hen health and welfare.


Asunto(s)
Proteínas de Fase Aguda/análisis , Contaminación del Aire Interior/efectos adversos , Amoníaco/toxicidad , Pollos/inmunología , Citocinas/análisis , Inmunoglobulinas/sangre , Animales , Citocinas/genética , Citocinas/metabolismo , Femenino , Expresión Génica , ARN Mensajero , Bazo/inmunología , Bazo/metabolismo
9.
Poult Sci ; 95(6): 1457-64, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26944974

RESUMEN

This study evaluated the effects of dietary probiotic supplement and postmortem storage on meat quality of chicken breast during retail display. A total of 35 birds were randomly obtained from 3 feeding groups (control without probiotic supplement, 250 ppm Sporulin, and 500 ppm PoultryStar). The probiotic supplement had no influence on feed conversion ratio and body weight gain, as well as body weight at 29 and 44 d (P > 0.05). After slaughter, each side of the breast muscles (M. Pectoralis major) was assigned to either one d or 5 d of postmortem storage. Probiotic supplement had no influence on the rate of pH decline of chicken breast muscles during the initial 6 h postmortem (P > 0.05). No interactions between probiotic supplement and postmortem storage on meat quality were found (P > 0.05). Postmortem storage decreased drip loss from 25.30 to 18.05% (P < 0.05). Probiotics-fed chicken groups, particularly PoultryStar treatment, had a higher myofibrillar fragmentation index than the control group (P < 0.05). However, shear force values were not affected by the probiotic treatments. Decreases in color and lipid stabilities of breast muscles were found during display (P < 0.05), but were not affected by the probiotic supplement (P > 0.05). Our result suggests that probiotic supplement had no adverse impacts on proteolysis and oxidative changes during 5 d postmortem display storage.


Asunto(s)
Almacenamiento de Alimentos , Carne/análisis , Músculos Pectorales/fisiología , Probióticos/química , Alimentación Animal/análisis , Animales , Pollos , Dieta/veterinaria , Masculino , Probióticos/administración & dosificación , Distribución Aleatoria
10.
Clin Chim Acta ; 450: 190-5, 2015 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-26319885

RESUMEN

BACKGROUND: We investigated the association between serum ferritin and carotid artery lesions in populations with abnormal glucose metabolism. METHODS: We included 70 participants with abnormal glucose metabolism and 170 participants with normal glucose metabolism and measured their baseline serum ferritin levels. During follow-up carotid intima-media thickness and carotid plaque were evaluated. RESULTS: Serum ferritin levels were higher in the participants with abnormal glucose metabolism (p<0.01). We further divided the patients with abnormal glucose metabolism into subgroups with and without intima-media proliferation, and found that ferritin was excluded from the final equation in the logistic regression. Furthermore, age, waist circumference, ferritin, 2h-PG, and total cholesterol were significantly different between the subgroups with and without carotid plaque. When the above data were included in a logistic regression model, the p values obtained for age, ferritin, and 2h-PG were 0.004, 0.032, and 0.011, respectively. CONCLUSIONS: In the Chinese population, serum ferritin levels are significantly increased in patients with abnormal glucose metabolism. The carotid intima-media thickness showed no independent relationship with serum ferritin in patients with abnormal glucose metabolism. However, high serum ferritin is an important risk factor for carotid atherosclerosis in these patients.


Asunto(s)
Enfermedades de las Arterias Carótidas/sangre , Enfermedades de las Arterias Carótidas/metabolismo , Grosor Intima-Media Carotídeo , Ferritinas/sangre , Glucosa/metabolismo , Placa Aterosclerótica/sangre , Placa Aterosclerótica/metabolismo , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/diagnóstico por imagen
11.
Poult Sci ; 93(6): 1318-26, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24879681

RESUMEN

Egg laying strains of chickens have a strong motivation to perch. Providing caged chickens with perches allows them to perform their natural perching behavior and also improves their musculoskeletal health due to exercise. Little is known about the effect of perch access for hens on physiological measures of stress. Our hypothesis was that denying chickens access to perches would elicit a stress response. The objective of this study was to determine the effect of perch access during all or part of life cycle on physiological homeostasis in caged 71-wk-old White Leghorn hens. A total of 1,064 chicks were assigned randomly to cages with and without perches (n = 14 pullet cages/perch treatment) on day of hatch. As pullets aged, chicks were removed from cages to provide more space. At 17 wk of age, 324 chickens in total were assigned to laying cages consisting of 4 treatments with 9 replicates per treatment. Treatment 1 chickens never had access to perches during their life cycle. Treatment 2 chickens had access to perches only from 17 to 71 wk of age (laying phase). Treatment 3 chickens had access to perches only from hatch to 16.9 wk of age (pullet phase). Treatment 4 chickens always had access to perches during their life cycle. At 71 wk of age, chickens were sampled for measurement of plasma catecholamines (epinephrine, norepinephrine, and dopamine) and corticosterone; blood serotonin and Trp; fluctuating asymmetry of shank length and width; and adrenal weight. Only shank width differed among treatments. Chickens with previous exposure to perches during the pullet phase had wider shanks than chickens without access to perches (P = 0.006), suggesting that early perching promoted skeletal development. These results suggest that a stress response was not elicited in 71-wk-old White Leghorn hens that always had access to perches compared with hens that never had access to perches during all or part of their life cycle.


Asunto(s)
Crianza de Animales Domésticos/métodos , Catecolaminas/sangre , Pollos/fisiología , Corticosterona/sangre , Bienestar del Animal , Animales , Pollos/crecimiento & desarrollo , Cromatografía Líquida de Alta Presión/veterinaria , Femenino , Vivienda para Animales , Radioinmunoensayo/veterinaria , Distribución Aleatoria , Reproducción , Estrés Fisiológico
12.
Poult Sci ; 93(7): 1618-22, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24812236

RESUMEN

Fatty liver is a common energy metabolic disorder in caged laying hens. Considering that the egg industry is shifting from conventional cages to alternative housing systems such as enriched cages, the objective of this study was to determine the effects of perches on fat deposition and liver health in laying hens. Three hundred twenty-four 17-wk-old White Leghorn hens were housed in 1 of 4 treatments with 9 hens per cage. Treatment 1 hens never had access to perches during their life cycle. Treatment 2 hens had access to perches during the pullet phase only. Treatment 3 hens had access to perches during the laying phase only. Treatment 4 hens always had access to perches. Liver weight, abdominal fat pad weight, BW, liver fat, and circulating alanine transaminase, aspartate transaminase, and adiponectin were determined. Provision of perches during either the rearing or laying phase did not affect liver health in 71-wk-old hens. However, perch access compared with no perch access during the egg laying phase reduced relative fat pad weight. These results suggest that providing perches as a means of stimulating activity reduced abdominal fat deposition in caged hens during the laying period. However, perch access in caged hens was ineffective in reducing fat deposition in the liver and altering enzyme activities related to improved liver function.


Asunto(s)
Grasa Abdominal/metabolismo , Pollos/fisiología , Vivienda para Animales/normas , Hígado/metabolismo , Actividad Motora , Crianza de Animales Domésticos/instrumentación , Animales , Femenino , Hígado/enzimología , Distribución Aleatoria
13.
Poult Sci ; 92(11): 2853-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24135587

RESUMEN

The neuroendocrine system controls animals' adaptability to their environments by releasing psychotropic compounds such as catecholamines [epinephrine (EP), norepinephrine (NE), and dopamine (DA)], corticosterone (CORT), and serotonin (5-hydroxytryptamine or 5-HT). Changes of these neuroendocrine compounds have been used as biomarkers of animals' stress responses associated with their well-being. Assuming that pullets, like laying hens, are highly motivated to perch, we hypothesize that pullets with access to perches will experience less stress than pullets that never have access to perches. The objective of this study was to examine the effects of perch access and age on physiological measurements of stress in White Leghorn pullets housed in conventional cages. Hatchlings (n = 1,064) were randomly assigned to 28 cages. Two parallel metal round perches were installed in each of 14 cages assigned the perch treatment, whereas control cages were without perches. Two birds per cage were bled at wk 4, 6, and 12 wk of age. Plasma levels of CORT, DA, EP, and NE, blood concentrations of 5-HT and Trp, and heterophil to lymphocyte ratios were measured. Data were analyzed using a 2-way ANOVA. The perch treatment or its interaction with age did not affect any parameter measured in the study. The increase in the concentrations of circulating EP, NE, 5-HT (numerical increase at 4 wk), and Trp in 4- and 6-wk-old pullets compared with 12-wk-old pullets is unclear, but may have been due to acute handling stress at younger ages. In contrast, concentrations of DA were less at 4 wk compared with levels at 6 and 12 wk of age. Plasma CORT levels and the heterophil to lymphocyte ratio, indicators of long-term stress, were unaffected by age (P = 0.07 and 0.49, respectively). These results indicated that age, but not perch access, affects neuroendocrine homeostasis in White Leghorn pullets. Pullets that were never exposed to perches showed no evidence of eliciting a stress response.


Asunto(s)
Monoaminas Biogénicas/sangre , Pollos/fisiología , Corticosterona/sangre , Vivienda para Animales , Leucocitos/citología , Crianza de Animales Domésticos , Animales , Análisis Químico de la Sangre/veterinaria , Pollos/crecimiento & desarrollo , Cromatografía Líquida de Alta Presión/veterinaria , Femenino , Terapia de Inmunosupresión , Radioinmunoensayo/veterinaria , Distribución Aleatoria , Estrés Fisiológico
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