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1.
Chemosphere ; 338: 139496, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37451642

RESUMEN

Mercury is a metal of toxicological importance that occurs naturally. However, its concentration can be affected by anthropogenic activities and has the potential to bioaccumulate and biomagnify in food webs. Thus, knowing how its concentration varies along the trophic levels allows us to understand its potential risks to the biota. The present study aimed to investigate mercury transfer through the Stenella frontalis food web in Ilha Grande Bay (IGB), Rio de Janeiro state, Brazil. Samples of muscle and liver of S. frontalis were obtained from carcasses (n = 8) found stranded in the IGB, and its potential prey species were collected in fishing landings in the same Bay (n = 145). Total mercury (THg) concentrations were determined by atomic absorption spectrometry, and the δ15N was determined by an isotope ratio mass spectrometer. To investigate how trophic transfer affects mercury contamination in biota, six linear models were applied between THg logarithmic concentrations and δ15N or trophic position (TP). The trophic magnification factor (TMF) was calculated from each model to estimate the trophic transfer. Mean THg concentration in S. frontalis was higher in the liver than in muscle, but no correlation was found with age and δ15N values. Instead, the hepatic and muscular THg concentrations positively correlated with the trophic position. In the summer, THg concentration, TP, and δ15N values in prey species varied significantly, as well as in the winter, except for THg concentration. All trophic transfer models were significant in both seasons, and the TMF >1. The present study showed that trophic transfer is an essential factor in mercury biomagnification in both seasons but is not the unique driver. Both δ15N and TP could explain mercury trophic transfer, but TP better integrates metabolic diversity and seasonality.


Asunto(s)
Delfines , Mercurio , Stenella , Contaminantes Químicos del Agua , Animales , Mercurio/análisis , Stenella/metabolismo , Bioacumulación , Delfines/metabolismo , Brasil , Cadena Alimentaria , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Peces/metabolismo
2.
Trop Anim Health Prod ; 54(5): 281, 2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36074277

RESUMEN

This study aimed to assess the effect of adding clinoptilolite in the diet on uterine health and reproductive performance in multiparous lactating dairy cows managed in a tropical pasture-based system above 2500 m of altitude. Seventy-seven multiparous Holstein crossbred cows from two farms were allocated randomly into two groups: clinoptilolite supplemented cows (CLG, n = 42) and non-supplemented cows as control (CG, n = 35). Cows from CLG were supplemented with clinoptilolite from 30 days (50 g/cow/day) before to 60 days after calving (200 g/cow/day). In CLG cows, percentages of uterine PMN leukocytes (P < 0.0001) and proportion of subclinical endometritis (P = 0.0187) were lower than in CG. The interval calving to first corpus luteum was shorter (P = 0.0759) in CLG than CG, and calving to first service interval was similar between treatments. Cows from CLG became pregnant 35 days earlier than CG cows (P = 0.0224). On farm A, calving to conception interval was 18.1 days longer in CLG than in CG (P = 0.3750); in farm B, this interval was 86.2 days shorter in CLG than in CG (P = 0.0002). In conclusion, daily addition of clinoptilolite in the diet decreased the percentage of uterine PMN leukocytes, the proportion of cows with subclinical endometritis, and shortened the calving-conception interval in multiparous lactating dairy cows.


Asunto(s)
Endometritis , Animales , Bovinos , Dieta/veterinaria , Endometritis/prevención & control , Endometritis/veterinaria , Femenino , Lactancia , Leucocitos , Periodo Posparto , Embarazo , Zeolitas
3.
Rev. colomb. cienc. pecu ; 35(2)jun. 2022.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1535787

RESUMEN

Background: No dairy breed or crossbreed has superior overall performance in all environments; therefore, it is necessary to determine which crossbreed is the most suitable for the Mexican tropic and what proportion of European breed is optimum for reproduction. Objective: To assess the effect of the proportion of Bos taurus (Bt) genes on reproductive performance of Holstein×Zebu (HZ) and Brown Swiss×Zebu (BZ) cows, and compare reproductive performance of these genotypes in a dual- purpose production system. Methods: Cows were maintained in a rotational grazing system on African star grass (Cynodon plectostachyus) in Veracruz, Mexico. Cows were milked twice daily. Calves were kept tied to the side of their dams while the cows were milked. Results: The percentage of Bt genes did not affect (p>0.05) fertility traits (age at first calving, days to first service after calving, services per conception, conception rate at first service, days open until conception, gestation length, and calving interval) of BZ cows. In contrast, HZ cows with less than 75% Holstein (H) genes were 0.3 years younger (p<0.05) at first calving and had 39.8 fewer days open (p<0.05) than HZ cows with 75% H genes or more. In addition, the calving interval of HZ cows with less than 75% H genes was 44.8 days shorter (p<0.05) than that of HZ cows with 75% H genes or more. The HZ cows had five fewer days pregnant and were 22.8 kg heavier at calving (p<0.05) than BZ cows. Conclusions: The effect of the percentage of Bt genes on cow fertility depends on the dairy breed used. In general, BZ and HZ cows present similar reproductive performance.


Antecedentes: Ninguna raza lechera o cruce tiene un desempeño general superior en todos los ambientes; por lo tanto, es necesario determinar cuál cruce lechero es más apropiado en el trópico mexicano y qué proporción de raza europea es óptima para la reproducción. Objetivo: Evaluar el efecto de la proporción de genes Bos taurus (Bt) en el desempeño reproductivo de vacas cruzadas Holstein×Cebú (HC) y Pardo Suizo×Cebú (PC), y comparar el desempeño reproductivo de estos dos genotipos en un sistema de producción doble propósito. Métodos: Las vacas se mantuvieron en un sistema de pastoreo rotacional en zacate Estrella de África (Cynodon plectostachyus) en Veracruz, México. Las vacas se ordeñaron dos veces al día. Los becerros se mantuvieron atados, a un costado de sus madres mientras éstas se ordeñaron. Resultados: El porcentaje de genes Bt no afectó (p>0,05) ninguna característica de fertilidad (edad a primer parto, días a primer servicio después del parto, servicios por concepción, tasa de preñez a primer servicio, días abiertos a la concepción, duración de la gestación, e intervalo entre partos) de las vacas PC. En contraste, las vacas HC con menos de 75% de genes Holstein (H) fueron 0,3 años más jóvenes (p<0,05) al primer parto y tuvieron 39,8 días abiertos menos (p<0,05) que las vacas HC con 75% de genes H o más. Además, el intervalo entre partos de las vacas HC con menos de 75% de genes H fue 44,8 días más corto (p<0,05) que el de las vacas HC con 75% de genes H o más. Las vacas HC tuvieron cinco días de gestación menos y fueron 22,8 kg más pesadas al parto (p<0,05) que las PC. Conclusiones: El efecto del porcentaje de genes Bt sobre la fertilidad de la vaca depende de la raza lechera usada. En general, las vacas PC y HC tienen similar desempeño reproductivo.


Antecedentes: Nenhuma raça ou cruza leiteira tem desempenho geral superior em todos os ambientes; portanto, é necessário determinar qual cruza leiteira é mais apropriada no trópico mexicano e qual proporção da raça europeia é ideal para a reprodução das vacas. Objetivo: Avaliar o efeito da proporção de genes Bos taurus (Bt) no desempenho reprodutivo de vacas Holandês×Zebu (HZ) e Pardo Suíço×Zebu (PZ), e comparar o desempenho reprodutivo desses dois genótipos em sistema de produção de dupla aptidão. Métodos: As vacas foram mantidas em sistema de pastoreio rotacional em capim Estrela de África (Cynodon plectostachyus) em Veracruz, México. As vacas foram ordenhadas duas vezes por dia. Os bezerros foram mantidos ao lado de suas mães enquanto eram ordenhadas. Resultados: A porcentagem dos genes Bt não afetou (p>0,05) nenhuma característica de fertilidade (idade ao primeiro parto, número de dias para o primeiro serviço pós-parto, serviços por concepção, taxa de prenhes no primeiro serviço, dias abertos, período de gestação e intervalo entre partos) das vacas PZ. Em contraste, vacas HC com menos de 75% dos genes Holandês (H) eram 0,3 anos mais jovens (p<0,05) no primeiro parto e tiveram 39,8 dias abertos a menos (p<0,05) do que as vacas HZ com 75% ou mais dos genes H. Além disso, o intervalo de parto das vacas HZ com menos de 75% dos genes H foram 44,8 dias mais curtos (p<0,05) do que as vacas HZ com 75% ou mais de genes H. As vacas HZ tiveram cinco dias de gestação a menos e foram 22,8 kg mais pesadas no parto (p<0,05) do que as PZ. Conclusões: O efeito da porcentagem de genes Bt na fertilidade da vaca dependeu da raça leiteira utilizada. Em geral, as vacas PZ e HZ tiveram desempenho reprodutivo semelhante.

4.
Sci Total Environ ; 837: 155792, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35550892

RESUMEN

Mining of deep-sea Fe-Mn deposits will remove crusts and nodules from the seafloor. The growth of these minerals takes millions of years, yet little is known about their microbiome. Besides being key elements of the biogeochemical cycles and essential links of food and energy to deep-sea, microbes have been identified to affect manganese oxide formation. In this study, we determined the composition and diversity of Bacteria and Archaea in deep-sea Fe-Mn crusts, nodules, and associated sediments from two areas in the Atlantic Ocean, the Tropic Seamount and the Rio Grande Rise. Samples were collected using ROV and dredge in 2016 and 2018 oceanographic campaigns, and the 16S rRNA gene was sequenced using Illumina platform. Additionally, we compared our results with microbiome data of Fe-Mn crusts, nodules, and sediments from Clarion-Clipperton Zone and Takuyo-Daigo Seamount in the Pacific Ocean. We found that Atlantic seamounts harbor an unusual and unknown Fe-Mn deposit microbiome with lower diversity and richness compared to Pacific areas. Crusts and nodules from Atlantic seamounts have unique taxa (Alteromonadales, Nitrospira, and Magnetospiraceae) and a higher abundance of potential metal-cycling bacteria, such as Betaproteobacteriales and Pseudomonadales. The microbial beta-diversity from Atlantic seamounts was clearly grouped into microhabitats according to sediments, crusts, nodules, and geochemistry. Despite the time scale of million years for these deposits to grow, a combination of environmental settings played a significant role in shaping the microbiome of crusts and nodules. Our results suggest that microbes of Fe-Mn deposits are key in biogeochemical reactions in deep-sea ecosystems. These findings demonstrate the importance of microbial community analysis in environmental baseline studies for areas within the potential of deep-sea mining.


Asunto(s)
Sedimentos Geológicos , Microbiota , Archaea , Bacterias , Sedimentos Geológicos/química , Océano Pacífico , ARN Ribosómico 16S/genética
5.
Trop Anim Health Prod ; 53(6): 545, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34779918

RESUMEN

For the past several decades, selective anthelmintic therapy (SAT) has been recommended in temperate climate countries for controlling gastrointestinal parasites in horses. However, the feasibility of this approach in tropical climates remains unknown, given the very different parasite transmission patterns and a larger representation of working equids. The aim of this study was to evaluate the bio-economic feasibility of SAT in horses kept under tropical conditions of Camagüey, Cuba. Fecal egg counts were determined from 794 adult horses and used for evaluating three different putative treatment thresholds; > 500 strongylid eggs per gram of feces (EPG); > 1000 EPG; and treatments yielding > 80% of the total herd egg output. These scenarios were evaluated under three treatment frequencies (every 2, 6, and 12 months). The bio-economic feasibility of these nine possible selective anthelmintic therapy scenarios was evaluated taking into account the cost of parasitological tests, and the mean cost of anthelmintic treatment in Camagüey. The majority (96.7%) of the samples tested were positive for strongyle eggs, with a mean of 1549 EPG. The percentage of horses exceeding the cut-off points at the nine scenarios varied between 40.1 and 93.8%. All owners surveyed used extra-label anthelmintic product in their horses on a routine basis. The economic analysis demonstrated that selective therapy generally was much more costly than deworming the entire herd without determining egg counts. However, we consider that the deworming every 6 months of the horses that expel 80% of the eggs in the herd allows a reduction of the treatment intensity without increasing costs, and it can be considered as a viable selective deworming scheme under similar conditions.


Asunto(s)
Antihelmínticos , Enfermedades de los Caballos , Infecciones Equinas por Strongyloidea , Animales , Antihelmínticos/uso terapéutico , Estudios de Factibilidad , Heces , Enfermedades de los Caballos/tratamiento farmacológico , Caballos , Óvulo , Recuento de Huevos de Parásitos/veterinaria , Infecciones Equinas por Strongyloidea/tratamiento farmacológico
6.
7.
Trop Anim Health Prod ; 53(2): 323, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33991243

RESUMEN

The objective of this study was to evaluate feed intake and digestibility and ruminal characteristics of development-stage calves fed mulatto II (Brachiaria sp.) grass hay (MGH) and a protein supplement (PS) consisting of increasing levels of the parota (Enterolobium cyclocarpum) pod (PP). We used eight Swiss-zebu calves in growth stage with an average age of 11 months and initial average weight of 157.6 ± 8.5 kg. They were distributed in a repeated 4 × 4 Latin square design with 4 treatments (period 30 days): 0% (PP0), 25% (PP25), 50% (PP50), and 75% (PP75) of the PP. Calves in the PP0 and PP25 treatments had higher intake of PS and MGH as dry matter (DM) than those in the PP50 and PP75 treatments (p < 0.05). Organic matter intake (OMI) of the PP75 calves was lower than that of PP0 and PP25 calves. Crude protein intakes (CPI) of PP0 and PP25 calves were higher than those of PP50 and PP75 calves (p < 0.05). Apparent digestibility of crude protein was higher in the PP0, PP25, and PP50 treatments compared with that in treatment PP75 (p < 0.05). The treatments did not affect total bacterial count, cellulolytic bacterial count, cellulase enzymatic activity, volatile fatty acids, or the acetate/propionate ratio (p > 0.05). Rumen pH in the PP0 calves was higher than that of the PP25 calves, whereas the protozoa count and ammonia content were higher in PP0 calves than in PP75 (p < 0.05). In conclusion, the inclusion of 25% PP in the PS for forage-fed calves is a feeding alternative.


Asunto(s)
Alimentación Animal , Rumen , Alimentación Animal/análisis , Animales , Bovinos , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Digestión , Ingestión de Alimentos , Fermentación , Rumen/metabolismo , Destete
8.
Trop Anim Health Prod ; 53(2): 294, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33909176

RESUMEN

The effect of supplementation of grazing cattle with unconventional agro-industrial by-products on milk production and economic performance was evaluated in the Amazon region of Peru. Ten lactating cows were used in a simple crossover design with two periods of 21 days (11 days of adaptation and 10 days of measurements), and two treatments: conventional supplementation (rice polishing) and a mixture of unconventional agro-industrial by-products-MUABP (rice polishing, rice middling, cocoa hull, and coconut meal). Cattle supplemented with MUABP produced more milk than those fed the conventional supplement (10.2 vs. 8.8 kg/cow/day, p <0.001). No differences were found between the two treatments in protein, fat, or lactose content of milk (3.9%, 3.17%, 4.54% on average respectively; p ≥0.05). Daily weight gain with the MUABP treatment was 0.09 kg/day, while with conventional supplementation cow lost -0.04 kg/day (p =0.01). Body condition did not differ between treatments (p ≥0.05). Income due to supplementation with unconventional agro-industrial by-product was US $0.2 in comparison with only rice polishing. Cattle supplemented with MUABP improved milk production and their economic profitability.


Asunto(s)
Dieta , Lactancia , Alimentación Animal/análisis , Animales , Bovinos , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Leche , Perú
9.
Front Allergy ; 2: 761492, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35387009

RESUMEN

Introduction: The severity of wheezing episodes is related with the need for health services, but the factors associated with health care utilization in preschool recurrent wheezers in underdeveloped regions are unclear. Objective: To evaluate the factors associated with health care utilization in preschool recurrent wheezers in Cartagena, Colombia. Methods: One hundred twenty-seven recurrent wheezers (age 2-6 years old) who were admitted to the emergency room (ER) due to wheezing in a Pediatric reference hospital in Cartagena were included. Children were evaluated by means of questionnaires and classified according to the number of ER visits, need for hospitalization and history of intensive care unit (ICU) admission due to wheezing within the last year. Total serum IgE and specific IgE to house dust mite allergens (HDM) were measured by ImmunoCAP® and allergen sensitization was evaluated by skin prick tests (SPT). Results: The maternal report of nocturnal cough without fever in their children increased the risk to have ≥5 ER visits in the last year due to wheezing. The use of montelukast was negatively associated with hospitalization, while a history of pneumonia and lack of tap water, increased the risk of hospitalization due to wheezing. A history of bronchiolitis, family history of asthma, cohabiting with two or more siblings, passive exposure to smoke and lack of sewage facilities increased the risk of ICU admission due to wheezing. The presence of atopy evaluated by SPT reactivity, total IgE levels or specific IgE to HDM were not associated with health care utilization. We also found that seroprevalence of positive IgE (≥0.35 kU/L) was 27% to B. tropicalis and 20.3% to D. pteronyssinus but the prevalence of positive IgE sensitization to these allergens was below 2% and 8% when evaluated by SPT, respectively. Conclusions: Poverty indicators are associated with ICU admission in a group of preschool recurrent wheezers and should be considered as aggravating factors for wheezing. These factors must be systematically assessed in the medical approach in underdeveloped regions in the tropics. Nocturnal cough without fever is a symptom associated with frequent ER visits while atopy was not associated with health care utilization in preschool recurrent wheezers.

10.
Rev. biol. trop ; Rev. biol. trop;69(1)2021.
Artículo en Español | SaludCR, LILACS | ID: biblio-1507823

RESUMEN

Introducción: Erythrina americana es una leguminosa arbórea que se encuentra como parte del cerco en las fincas ganaderas de la región tropical. Sin embargo, los productores de ovinos no utilizan el follaje de este tipo de leguminosa de forma rutinaria o estratégica como complemento alimenticio debido, en parte, por el desconocimiento de su composición química y rendimiento foliar, así como, por los factores que los afectan. Objetivo: Determinar la influencia de la época climática y diámetro del árbol E. americana en la composición química y rendimiento de follaje a una edad de rebrote de 90 días. Método: Se utilizaron 47 árboles en un diseño de dos factores. Los factores fueron época (sequía y lluvias) y diámetro del árbol a 0.20 m de altura del suelo (D-9 entre 0.05 y 0.09 m y D-13, entre 0.091 y 0.13 m). Las variables respuesta fueron producción de materia seca y proteína bruta foliar (kg árbol-1). Resultados: La época no afectó (P > 0.05) la producción de materia seca y proteína bruta. Sin embargo, el diámetro de E. americana si las afectó (P < 0.01). En el diámetro D-13 se detectó la mayor producción de materia seca y proteína bruta foliar con respecto a D-9. Conclusión: El diámetro del árbol tuvo mayor influencia que la época en el rendimiento de materia seca y proteína bruta foliar.


Introduction: Erythrina americana is a tree legume found as part of the fence of livestock farms of the tropical region. However, sheep farmers do not routinely or strategically use the foliage of this type of legume as a dietary supplement due, in part, to ignorance of its chemical composition and foliar performance, as well as the factors that affect them. Objective: To determine the influence of season and diameter of E. americana tree on the chemical composition and foliage yield at a 90-day regrowth age. Methods: 47 trees were used in a two-factor design. The factors were season (dry and rainy) and tree diameter at 0.20 m above ground level (D-9 between 0.05 and 0.09 m and D-13, between 0.091 to 0.13 m). The response variables were dry matter production and crude protein from foliage (kg árbol-1). Results: The season did not affect (P > 0.05) the production of dry matter and crude protein. However, the diameter of E. americana affected them (P < 0.01). In diameter D-13, the highest production of dry matter and crude foliar protein tree-1 was detected with respect to D-9. Conclusions: The diameter of the tree had a more influence than the season on yield of dry matter and crude protein.


Asunto(s)
Árboles/crecimiento & desarrollo , Erythrina/anatomía & histología , Fabaceae/química , Crianza de Animales Domésticos , México
11.
Heliyon ; 6(5): e04049, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32490249

RESUMEN

Improving the early detection of animals or herds at increased risk for diseases, reduced milk yield or impaired reproductive performance should be an essential component of herd health programs. The present study aimed to describe the findings of hematological, biochemical, and milk analytes of grazing cows from tropical dairy herds during the early postpartum period, and the effects of parity and calving season. In the North of Antioquia, Colombia which is the major area of specialized dairy production in the country, a longitudinal study comprising 260 dairy cows selected at calving, was conducted. Blood and milk sampling were made to establish red blood cell count, white blood cell count, minerals, protein traits and, milk composition. Variables were checked for normal distribution. The Box-Cox transformation was used when necessary. Variables were statistically analyzed using a GLM model considering parity and calving season as fixed effects. Using a parametric or non-parametric method based on the distribution of the variables, single average values, and 90% confidence intervals were determined considering fixed effects founds in the GLM model. Blood values affected by parity in lactating dairy cows grazing in highland tropical herds included serum calcium levels, red blood cell counts, hematocrit, hemoglobin, mean corpuscular hemoglobin, and total eosinophil counts, whereas blood values affected by season included: total leukocyte counts, total and differential lymphocyte counts, serum albumin and globulin concentration, and serum albumin:globulin ratio (P < 0.05). Data from our study could be used for comparison studies between lactating dairy cows within tropical herds or between tropical and seasonal dairy herds.

12.
J Equine Vet Sci ; 88: 102966, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32303317

RESUMEN

The aim of this observational study was to describe the characteristics of circuits performed by horses used in carriage tourism in a tropical city and discuss their implications as a challenge for animal welfare. The tourism circuit of 33 Criollo horses (400 ± 50 kg) was followed by using the GPS from August 31 to December 2nd, 2018, in the rainfall summer season. The environmental temperature, humidity, and accumulated rainfall were obtained from a local meteorological station. The distance and number of trips, the number of people transported, and the time taken for working and resting activities were also registered to report descriptive statistics. A total of 69 trips were observed with a mean distance of 5 ± 0.5 km traveled in 47 ± 16 minutes, the number of trips performed by the horses being as maximum as six per day, and a continuous pulling activity of 4 hours and 42 minutes. The horses rested one day after two consecutive working days; resting within the same day lasted from one to 8 hours. The trips respected the carts' capacity of 6 people including the driver (∼700 kg); mean daily temperature and relative humidity were 35.25 ± 1.54°C and 43.40 ± 6.58, respectively. No feed or water was offered during the carriage work. Considering that load-pulling capacity of light horses in low-friction surfaces can easily reach 2000 kg, carriage activity observed in the present study demand an under-maximum effort for horses. In addition, the length and intensity of workload does not imply a challenge for horse welfare. Nevertheless, watering practices could be improved and microweather conditions in warmer months should be monitored.


Asunto(s)
Turismo , Animales , Ciudades , Caballos , Humedad , Estaciones del Año , Temperatura
13.
Ecology ; 101(8): e03074, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32304220

RESUMEN

The input of external energy and matter in recipient ecosystems can act as a bottom-up force that subsidizes consumers, with subsequent cascading effects throughout the food web. Depending on the amount of input, dietary preference, and the strength of trophic links, allochthonous resources generally play a stabilizing role on food webs. In this study, we investigated the stabilizing role of allochthonous aquatic resources on intraguild predation (IGP) and their consequences on shared prey in a terrestrial ecosystem. To this end, we manipulated the input of emergent aquatic insects (the allochthonous resources) from streams to land, and predation pressure by bats and birds (the top predators), in a multitrophic food web using an orthogonal exclusion experiment. Using stable isotope metrics, we found that bats, birds, and spiders (the mesopredators), were highly subsidized by emergent aquatic insects. Moreover, among terrestrial prey, top predators fed more on spiders than insects. As predicted, spiders were strongly affected by the presence of top predators when allochthonous resources were excluded. Consequently, in this scenario terrestrial insects were two times more abundant. Because spiders showed a higher preference for consuming aquatic resources, we suggest that nonconsumptive effects of spiders upon terrestrial insects could be mediating the strong response of those shared prey. We demonstrate that the input of allochthonous aquatic resources can play a fundamental role in stabilizing terrestrial trophic interactions and trophic cascades in riparian zones via decreasing predation pressure.


Asunto(s)
Conducta Predatoria , Arañas , Animales , Ecosistema , Cadena Alimentaria , Insectos
14.
Med. interna Méx ; 35(4): 638-645, jul.-ago. 2019. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1287175

RESUMEN

Resumen La diabetes insípida central es un trastorno ocasionado por la deficiencia total o parcial de la síntesis, secreción o ambas de la hormona antidiurética, causada por una disfunción hipotálamo-hipofisaria que resulta en un síndrome poliúrico con polidipsia severa. Este trastorno puede ser primario, debido a anormalidades genéticas, o secundario a lesiones posquirúrgicas, traumáticas, infecciosas o tumorales. Describimos el caso de un paciente de 15 años de edad al momento del diagnóstico. En la primera visita el paciente tenía un claro síndrome poliúrico. La resonancia magnética de cráneo mostró únicamente un aracnoidocele selar; sin embargo, en el estudio de seguimiento realizado ocho meses después se encontró engrosamiento del tallo hipofisario y una lesión osteolítica en el hueso parietal izquierdo. El paciente fue tratado con resección quirúrgica de la lesión lítica, seguida de 12 ciclos de quimioterapia. Dos años después se confirmó hipogonadismo hipogonadotrópico. La ausencia de lesiones al momento del diagnóstico no excluye la posibilidad de que se hagan aparentes las lesiones tumorales clásicas, como en nuestro caso, en el que únicamente aparecía un aracnoidocele inicial y pocos meses después se hizo evidente el engrosamiento del tallo hipofisario y la metástasis osteolítica.


Abstract Central diabetes insipidus is a disorder produced by total or partial deficiency in the synthesis or secretion of antidiuretic hormone caused by hypothalamic-hypophyseal dysfunction, which results in a polyuric syndrome with severe polydipsia. This disorder may be primary when it is caused by genetic abnormalities, or secondary to postoperative, traumatic, infectious or tumoral lesions. This paper reports the case of a male patient, admitted at the endocrine clinic at the age of 15 with a severe polyuric syndrome. At the time of diagnosis of diabetes insipidus, a magnetic resonance was performed demonstrating only a sellar arachnoidocele; however, in the follow-up study conducted eight months later, we found a marked thickening of the hypophyseal stalk and an osteolytic lesion on the left parietal bone. The patient was treated by surgical resection of the lytic parietal bone lesion, followed by 12 cycles of chemotherapy. Two years later, we confirmed the diagnosis of hypogonadotropic hypogonadism. Absent lesions at moment of diagnosis do not exclude the possibility of the appearance of classic tumoral lesions on follow-up studies, like in our case in which only the initial aracnoidocele appeared, but few months later a thickening of the hypophyseal stalk and bone metastasis became evident.

15.
Environ Pollut ; 241: 800-809, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29909306

RESUMEN

A pesticide monitoring study including 80 and 60 active ingredients (in surface waters and sediments, respectively) was carried out in a river basin in Costa Rica during 2007-2012. A special emphasis was given on the exceptional ecological conditions of the tropical agro-ecosystem and the pesticide application strategies in order to establish a reliable monitoring network. A total of 135 water samples and 129 sediment samples were collected and analyzed. Long-term aquatic ecotoxicological risk assessment based on risk quotient in three trophic levels was conducted. Short-term risk assessment was used to calculate the toxic unit and prioritization of sampling sites was conducted by the sum of toxic units in both aquatic and sediment compartments. Dimethoate (61.2 µg/L), propanil (30.6 µg/L), diuron (22.8 µg/L) and terbutryn (4.8 µg/L) were detected at the highest concentrations in water samples. Carbendazim and endosulfan were the most frequently detected pesticides in water and sediment samples, respectively. Triazophos (491 µg/kg), cypermethrin (71.5 µg/kg), permethrin (47.8 µg/kg), terbutryn (38.7 µg/kg), chlorpyrifos (18.2 µg/kg) and diuron (11.75 µg/kg) were detected at the highest concentrations in sediment samples. The pesticides carbendazim, diuron, endosulfan, epoxyconazole, propanil, triazophos and terbutryn showed non-acceptable risk even when a conservative scenario was considered. Sum TUsite higher than 1 was found for one and two sampling sites in water and sediment compartments, respectively, suggesting high acute toxicity for the ecosystem. MAIN FINDING OF THE WORK: Exceptional ecological conditions of the tropical agro-ecosystem affect the fate of pesticides in water and sediment environment differently than the temperate one.


Asunto(s)
Agricultura , Ecotoxicología , Monitoreo del Ambiente , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Bencimidazoles , Carbamatos , Cloropirifos , Costa Rica , Ecosistema , Endosulfano , Sedimentos Geológicos , Plaguicidas/toxicidad , Medición de Riesgo , Ríos , Triazinas , Contaminantes Químicos del Agua/toxicidad
16.
Front Plant Sci ; 9: 495, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29731760

RESUMEN

High-resolution and automated image analysis of individual roots demonstrated that endogenous nitric oxide (NO) contribute significantly to gravitropism of Arabidopsis roots. Lowering of endogenous NO concentrations strongly reduced and even reversed gravitropism, resulting in upward bending, without affecting root growth rate. Notably, the asymmetric accumulation of NO along the upper and lower sides of roots correlated with a positive gravitropic response. Detection of NO by the specific DAF-FM DA fluorescent probe revealed that NO was higher at the lower side of horizontally-oriented roots returning to initial values 2 h after the onset of gravistimulation. We demonstrate that NO promotes plasma membrane re-localization of PIN2 in epidermal cells, which is required during the early root gravitropic response. The dynamic and asymmetric localization of both auxin and NO is critical to regulate auxin polar transport during gravitropism. Our results collectively suggest that, although auxin and NO crosstalk occurs at different levels of regulation, they converge in the regulation of PIN2 membrane trafficking in gravistimulated roots, supporting the notion that a temporally and spatially coordinated network of signal molecules could participate in the early phases of auxin polar transport during gravitropism.

17.
Int J Biometeorol ; 62(5): 741-771, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28905125

RESUMEN

An early method of biometeorological forecasts was developed for Cuba during the late 90s. It was based on the relationship between the daily occurrence of massive health crisis and the magnitude of the 24-h differences of partial density of oxygen in the air (PODA index). Ten years later, applying new technological facilities, a new model was developed in order to offer operational biometeorological forecast to Cuban health institutions. After a satisfactory validation process, the official bioforecast service to health institutions in Villa Clara province began on February of 2012. The effectiveness had different success levels: for the bronchial asthma crisis (94%), in the hypertensive crisis (88%), with the cerebrovascular illnesses (85%), as well as migraines (82%) and in case of cardiovascular diseases (75%) were acceptable. Since 2008, the application of the model was extended to other regions of the world, including some national applications. Furthermore, it allowed the beginning of regional monitoring of meteor-tropic effects, following the occurrence and movement of areas with higher weather contrasts, defined according to the normalized scale of PODA index. The paper describes the main regional results already available, with emphasis in the observed meteor-tropic effects increasing in all regions during recent years. It coincides with the general increase of energy imbalance in the whole climate system. Finally, the paper describes the current development of new global biometeorological forecast services.


Asunto(s)
Predicción , Meteorología/métodos , Modelos Teóricos , Vigilancia en Salud Pública/métodos , Enfermedades Cardiovasculares , Servicios Médicos de Urgencia/estadística & datos numéricos , Femenino , Humanos , Masculino , Trastornos Migrañosos , Mortalidad , Oxígeno/análisis , Enfermedades Respiratorias , Tiempo (Meteorología)
18.
Arq. bras. med. vet. zootec. (Online) ; 68(4): 1077-1084, jul.-ago. 2016. tab
Artículo en Inglés | VETINDEX | ID: vti-340753

RESUMEN

The aim of this study was to determine the influence of gender on pre-weaning growth, yield and weight of primal cuts of the carcass of Blackbelly x Pelibuey lambs. 16 twin lambs were used. The lamb gender was the fixed factor. The variables evaluated were: body weight at birth and at weaning, average daily weight gain, weight and yield of carcass and primal cuts: neck, arm, thorax, abdomen and leg. Gender did not affect (P>0.05) body weight at birth. However, the pre-weaning average daily weight gain and body weight at weaning were affected (P 0.05) by the gender. Hot carcass yield and weight and primal cuts were not affected (P>0.05) by the gender of the lamb. Nevertheless, the area of the Longissimus dorsi muscle and cavity fat were different between males and females (P 0.05) 11.5±0.73cm2 and 198±0.05 g vs 9.3±0.73cm2 and 282±0.05g, respectively. In conclusion, in twin lambs Blackbelly x Pelibuey males had greater average daily weight gain and body weight at weaning than females. Carcass yield and weight and primal cuts were not affected by the gender of the lamb. However, males had greater area of the L. dorsi muscle than females and these in turn had a greater amount of cavity fat than males.(AU)


Objetivou-se determinar a influência do gênero no crescimento pré-desmame, no rendimento e no peso dos cortes primários de carcaça de cordeiros Blackbelly x Pelibuey. Utilizaram-se 16 cordeiros gêmeos. Os dados foram analisados em um desenho completamente ao acaso, em que o gênero dos corderos foi o fator fixo. As variáveis avaliadas foram: peso vivo ao nascimento e ao desmame, ganho diário de peso, peso e rendimento de carcaças e dos cortes primários: pescoço, braço, tórax, abdômen e perna. O gênero não afetou (P>0,05) o peso vivo ao nascimento. No entanto, o ganho diário de peso e o peso vivo ao desmame foram afetados, sendo esses valores superiores nos machos (P 0,05). O peso e o rendimento das carcaças quentes e dos cortes primários não foram afetados (P>0,05) pelo gênero do cordeiro. Entretanto, a área do músculo Longissimus dorsi e a gordura cavitária foram diferentes entre machos e fêmeas (P 0,05): 11.5±0.73cm2 e 198±0.05g vs. 9.3±0.73cm2 e 282±0.05g, respectivamente. Em conclusão, nos cordeiros gêmeos Blackbelly x Pelibuey, os machos tiveram maior ganho diário de peso e maior peso vivo ao desmame do que as fêmeas. O peso e o rendimento da carcaça bem como os cortes primários não foram afetados pelo gênero do cordeiro. Todavia, os machos tiveram maior área do músculo L. dorsi que as fêmeas e estas tiveram maior quantidade de gordura cavitária que os machos.(AU)


Asunto(s)
Animales , Masculino , Femenino , Oveja Doméstica/crecimiento & desarrollo , Industria de la Carne , Tamaño de la Camada/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales Domésticos/crecimiento & desarrollo , Distribución por Sexo
19.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);68(4): 1077-1084, jul.-ago. 2016. tab
Artículo en Inglés | LILACS, VETINDEX | ID: lil-792476

RESUMEN

The aim of this study was to determine the influence of gender on pre-weaning growth, yield and weight of primal cuts of the carcass of Blackbelly x Pelibuey lambs. 16 twin lambs were used. The lamb gender was the fixed factor. The variables evaluated were: body weight at birth and at weaning, average daily weight gain, weight and yield of carcass and primal cuts: neck, arm, thorax, abdomen and leg. Gender did not affect (P>0.05) body weight at birth. However, the pre-weaning average daily weight gain and body weight at weaning were affected (P<0.05) by the gender. Hot carcass yield and weight and primal cuts were not affected (P>0.05) by the gender of the lamb. Nevertheless, the area of the Longissimus dorsi muscle and cavity fat were different between males and females (P<0.05) 11.5±0.73cm2 and 198±0.05 g vs 9.3±0.73cm2 and 282±0.05g, respectively. In conclusion, in twin lambs Blackbelly x Pelibuey males had greater average daily weight gain and body weight at weaning than females. Carcass yield and weight and primal cuts were not affected by the gender of the lamb. However, males had greater area of the L. dorsi muscle than females and these in turn had a greater amount of cavity fat than males.(AU)


Objetivou-se determinar a influência do gênero no crescimento pré-desmame, no rendimento e no peso dos cortes primários de carcaça de cordeiros Blackbelly x Pelibuey. Utilizaram-se 16 cordeiros gêmeos. Os dados foram analisados em um desenho completamente ao acaso, em que o gênero dos corderos foi o fator fixo. As variáveis avaliadas foram: peso vivo ao nascimento e ao desmame, ganho diário de peso, peso e rendimento de carcaças e dos cortes primários: pescoço, braço, tórax, abdômen e perna. O gênero não afetou (P>0,05) o peso vivo ao nascimento. No entanto, o ganho diário de peso e o peso vivo ao desmame foram afetados, sendo esses valores superiores nos machos (P<0,05). O peso e o rendimento das carcaças quentes e dos cortes primários não foram afetados (P>0,05) pelo gênero do cordeiro. Entretanto, a área do músculo Longissimus dorsi e a gordura cavitária foram diferentes entre machos e fêmeas (P<0,05): 11.5±0.73cm2 e 198±0.05g vs. 9.3±0.73cm2 e 282±0.05g, respectivamente. Em conclusão, nos cordeiros gêmeos Blackbelly x Pelibuey, os machos tiveram maior ganho diário de peso e maior peso vivo ao desmame do que as fêmeas. O peso e o rendimento da carcaça bem como os cortes primários não foram afetados pelo gênero do cordeiro. Todavia, os machos tiveram maior área do músculo L. dorsi que as fêmeas e estas tiveram maior quantidade de gordura cavitária que os machos.(AU)


Asunto(s)
Animales , Masculino , Femenino , Fenómenos Fisiológicos Nutricionales de los Animales , Tamaño de la Camada/fisiología , Industria de la Carne , Oveja Doméstica/crecimiento & desarrollo , Animales Domésticos/crecimiento & desarrollo , Distribución por Sexo
20.
Trop Anim Health Prod ; 48(3): 655-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26701832

RESUMEN

The aim of this study was to evaluate the "male effect" at the end of protocol with prostaglandins (PG) on estrus synchronization of hair sheep during breeding season (November-December) in Yucatan, Mexico. Twenty female Pelibuey sheep (weighting 38.2 ± 1.6 kg and body condition score of 2.5 ± 0.5) were randomly distributed in two groups (n = 10). Group T1 (control, PG), two doses of 50 µg of cloprostenol with 12 days between applications were applied; in the second group T2 (PG-ME), ewes received the same PG protocol plus the introduction of a male at the end of treatment. The interval of end treatment-onset of estrus was analyzed using survival test; the number of sheep with presence/absence of estrus was analyzed using Fisher's exact test. Ewes in estrus for groups T1 and T2 were 5 vs. 8, respectively. No significant differences were found as regards the interval end of treatment-onset of estrus (P > 0.05), as well as in total proportion of ewes with estrus and likewise in the duration of it (P > 0.05). We conclude that the protocol based on double dose of PGF2α with interval of 12 days combined with the male effect is efficient to induce luteolysis and estrus synchronization in hair sheep.


Asunto(s)
Cloprostenol/farmacología , Sincronización del Estro/efectos de los fármacos , Fármacos para la Fertilidad Femenina/farmacología , Ovinos/fisiología , Animales , Cruzamiento , Estro/efectos de los fármacos , Femenino , Masculino , México , Estaciones del Año , Clima Tropical
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