Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 341.106
Filtrar
1.
J Environ Qual ; 49(1): 228-235, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33016360

RESUMEN

Manure composting is a common management practice for cattle feedlots, but gaseous emissions from composting are poorly understood. The objective of this study was to quantify ammonia (NH3 ), nitrous oxide (N2 O), carbon dioxide (CO2 ), and methane (CH4 ) emissions from windrow composting (turning) and static stockpiling (nonturning) of manure at a commercial feedlot in Australia. An inverse-dispersion technique using an open-path Fourier transform infrared (OP-FTIR) spectrometer gas sensor was deployed to measure emissions of NH3 , N2 O, CO2 , and CH4 over a 165-d study period, and 29 and 15% of the total data intervals were actually used to calculate the fluxes for the windrow and stockpile, respectively. The nitrogen (N) lost as NH3 and N2 O emissions represented 26.4 and 3.8% of the initial N in windrow, and 5.3 and 0.8% of that in the stockpile, respectively. The carbon (C) lost as CO2 and CH4 emissions represented 44 and 0.3% of the initial C in windrow, and 54.8 and 0.7% of that in the stockpile, respectively. Total greenhouse gas (GHG) emissions from the manure windrow were 2.7 times higher than those of the stockpiled manure. This work highlights the value that could be accrued if one could reduce emissions of NH3 -N and N2 O-N from composting, which would retain manure N content while reducing GHG emissions.


Asunto(s)
Compostaje , Animales , Australia , Bovinos , Gases , Efecto Invernadero , Estiércol
2.
J Environ Qual ; 49(3): 628-639, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-33016385

RESUMEN

An integrated crop-livestock system (ICLS), when managed properly, can help in mitigating soil surface greenhouse gas (GHG) fluxes, especially carbon dioxide (CO2 ), methane (CH4 ), and nitrous oxide (N2 O). However, the impacts of an ICLS on GHG fluxes are poorly understood. The present study was conducted at two sites (northern Brookings [Brookings-N] and northwestern Brookings [Brookings-NW]) established in 2016 and 2017, respectively, under loamy soils in South Dakota. The specific objective was to evaluate the impact of cover crops (CCs) and grazed CCs under oat (Avena sativa L.)-CCs-maize (Zea mays L.) rotation on GHG fluxes. Study treatments included the following: (a) a legume-dominated CC (LdC), (b) a cattle-grazed LdC (LdC+G), (c) a grass-dominated CC (GdC), (d) a cattle-grazed GdC (GdC+G), and (e) one without CC or grazing (NC). Greenhouse gas monitoring occurred weekly during the growing crop seasons in 2016 and 2017 for Brookings-N and in 2017 and 2018 for Brookings-NW. Data showed that cumulative CO2 and N2 O fluxes at Brookings-N were lower for GdC+G (4042 kg C ha-1 for CO2 and 1499 g N ha-1 for N2 O) than for LdC+G (4819 kg C ha-1 for CO2 and 2017 g N ha-1 for N2 O), indicating the superiority of GdC+G over LdC+G in reducing GHG fluxes. However, no effect from grazed CC on cumulative CO2 and N2 O fluxes were observed at the Brookings-NW site. Cumulative CH4 flux was not affected by an ICLS at either site. This short-term investigation showed that, in general, CCs and grazing of CCs and maize residue did not impact GHG fluxes.


Asunto(s)
Gases de Efecto Invernadero , Animales , Bovinos , Productos Agrícolas , Óxido Nitroso/análisis , Suelo , Zea mays
3.
J Environ Qual ; 49(2): 324-334, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33016426

RESUMEN

Managing a sustainable dairy farm requires balancing phosphorus (P) imports and exports that enter and leave through the farm gate. Over the long term, P surpluses will elevate soil-test P concentrations above crop requirements through routine land applications of manure. The objectives of this study were aimed at Virginia dairy farms (a) to determine P mass balances, (b) to define potential guidelines for a sustainable and feasible zone of operation based on P balance and P use efficiency, and (c) to assess risk factors driving P surplus and P use inefficiencies. Data on farm-gate P imports and exports via feed, manure, crops, fertilizers, bedding, animals, and milk were collected for 58 dairy farms in Virginia. There was no relationship between farm P balance and milk production, indicating that a P surplus was not necessary for good milk productivity. A feasible P balance limit was calculated below which 75% of farms could operate, and this was 18.7 kg P ha-1 . Two risk factors were identified for farms having a P balance above this limit: (a) land application of poultry litter and (b) excessive import of P through feed. Combined dairy and beef operations generally had more land and a lower P balance, whereas having combined dairy and poultry did not raise the P balance as long as poultry litter was exported. Dairy farms in Virginia can operate with a sustainable P balance as long as they avoid using excessive poultry litter and pay attention to P imported through purchased feed.


Asunto(s)
Industria Lechera , Fósforo/análisis , Alimentación Animal/análisis , Animales , Bovinos , Granjas , Nitrógeno/análisis , Virginia
4.
J Environ Qual ; 49(5): 1435-1444, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33016451

RESUMEN

Chlortetracycline (CTC), an antimicrobial administered as a feed additive to cattle, swine, and poultry, is present in the corresponding manure. Land application of raw or processed (composted or stockpiled) manure provides a mechanism by which CTC (and other antimicrobials) enters the environment and becomes available for transport to surface receiving waters via rainfall or snowmelt runoff. Chlortetracycline has been detected in Canadian surface waters, but little has been reported on its fate in aquatic ecosystems. To address this knowledge gap, the dissipation of CTC-enol was monitored in deionized water and water typical of wetlands within the prairie region of Canada. In deionized water, CTC-enol tautomerized to CTC-keto, and both tautomers epimerized to 4-epi-CTC-enol and 4-epi-CTC-keto, respectively. Irreversible isomerization to iso-CTC occurred, which then epimerized to 4-epi-iso-CTC. In wetland water, although tauterization of CTC-enol to CTC-keto occurred, there was no evidence of the formation of the 4-epimers of either CTC-enol or CTC-keto. The major product formed in the wetland water was iso-CTC, some of which epimerized to 4-epi-iso-CTC. Although CTC-enol was shown to tautomerize to CTC-keto, the concentration of CTC-keto remained low in both deionized and wetland water, suggesting that the isomerization of CTC-enol to iso-CTC most likely occurred via CTC-keto. The dissipation of CTC-enol in wetland water was described by pseudo first-order kinetics with a DT50 (time required for 50% dissipation) value of 4.8 h. The short DT50 value of CTC and reduced antimicrobial activity of iso-CTC and 4-epi-iso-CTC suggest a lower probability for selection for CTC-resistant bacteria in Canadian Prairie aquatic ecosystems.


Asunto(s)
Clortetraciclina , Animales , Canadá , Bovinos , Ecosistema , Pradera , Isomerismo , Porcinos , Humedales
5.
J Environ Qual ; 49(4): 1000-1010, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33016497

RESUMEN

Expansion of subsurface drainage into forage production may have a deleterious effect on surface waters due to increased nitrogen and phosphorus loading. The impact of controlled subsurface drainage (CD) on nitrogen and phosphorus loss compared with free subsurface drainage (FD) in tile drainage water has been explored to a lesser extent from forage production systems. This study quantifies the effects of CD and FD on average seasonal concentrations and cumulative loads of the total suspended solids (TSS), nitrate nitrogen (NO3 -N), and dissolved reactive phosphorus (DRP) in subsurface drainage water from a poorly drained floodplain soil in a cereal rye (Secale cereale L.)-sorghum [Sorghum bicolor (L.) Moench] rotation with rotational cattle grazing. During all crop seasons of sorghum production (2010-2013), CD had 6.03-9.63 mg L-1 less NO3 -N than FD. Mean DRP concentration was significantly higher for CD than for FD during all seasons except for sorghum in 2012-2013. Average cumulative discharge was 38 and 314 m3 ha-1 less for CD than for FD during sorghum and cereal rye growing seasons, respectively. Controlled drainage had 0.68-6.14 kg ha-1 lower cumulative NO3 -N loads than FD. The DRP loads were dependent on discharge. During sorghum growing seasons, TSS and DRP loads were 79-90% lower in CD compared with FD. The ability to reduce drainage water flow from tiles and subsequent nitrogen and phosphorus loading with CD compared with FD in a floodplain soil indicates that CD can be effective best management practice for forage production systems.


Asunto(s)
Agricultura , Suelo , Animales , Bovinos , Nitrógeno , Nutrientes , Fósforo
6.
Am J Dent ; 33(5): 227-234, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33017523

RESUMEN

PURPOSE: To evaluate the influence of different post-endodontic techniques on the fatigue survival and biomechanical behavior of crowned restored central incisors. METHODS: The crowns of 69 bovine incisors were cut, and the roots were treated endodontically and assigned randomly into three groups (n=23): resin composite buildup (BUP), glass fiber post-retained resin composite buildup (GFP), and cast post-and-core (CPC). They received full crown preparation with 2 mm ferrule, and a leucite-reinforced ceramic crown was cemented adhesively. Three specimens from each group were tested monotonically. The remaining specimens were subjected to the stepwise stress fatigue test until fracture or suspension after 1.5 x 106 cycles in a chewing simulator. The load and step at which each specimen failed were analyzed by Kaplan-Meier and Mantel-Cox (log-rank test) statistics, followed by multiple pairwise comparisons, at 5% significance level. The three groups tested (BUP, GFP, and CPC) were 3D modeled (Rhinoceros 4.0) and the maximum principal stress (MPa) criteria were used to calculate the results using FEA. RESULTS: There was no statistical difference between the treatments regarding the load or the number of cycles (Mantel-Cox log-rank test for trend, X²= 0.015, df=1, P= 0.901, X²=3.171, df=1, P= 0.995). Crown cracks were the predominant failure mode, and oblique root fractures were only observed in groups GFP and CPC. In endodontically treated incisors with a 2-mm ferrule, the post-endodontic treatment had no significant effect on fatigue survival. Non-restorable fractures only occurred in teeth restored with posts. CLINICAL SIGNIFICANCE: Although the clinical significance of laboratory studies has some limitations, this study suggests that composite buildups without posts may be an option for restoring endodontically treated incisors with 2 mm ferrule height.


Asunto(s)
Incisivo , Técnica de Perno Muñón , Animales , Bovinos , Resinas Compuestas , Coronas , Análisis del Estrés Dental
7.
Rev Sci Tech ; 39(2): 481-490, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33046927

RESUMEN

Climate change is predicted to change the nature and distribution of global farming systems, and strategies will be needed to adapt and optimise global food-producing systems. If genomic technologies are to be useful in this scenario, there is a need for the careful definition of phenotypes and routine sample collection, as well as large-scale genotyping of animal populations. Genomic tools will greatly enhance the characterisation of available germplasm and exploration of local genetic resources, while faster and cheaper DNA sequencing is leading to an increased understanding of the underlying genetic basis of traits. The use of genomic tools to increase animal resilience, reduce methane emissions from cattle and sheep, improve disease resistance, decrease environmental impact, reduce competition for land and water and, finally, increase production may be the most feasible path for the future of livestock production. In this review, the authors discuss various genomic strategies in the light of climate change, focusing on the selection of resistant/tolerant animals, landscape genomics, metagenomics and gene editing.


Asunto(s)
Cambio Climático , Genómica , Agricultura , Animales , Bovinos , Genoma , Ganado , Ovinos
8.
Rev Sci Tech ; 39(2): 417-425, 2020 Aug.
Artículo en Español, Inglés | MEDLINE | ID: mdl-33046933

RESUMEN

This case study outlines the actions of Cuba's Veterinary Service, as part of the country's disaster risk reduction and management system, in response to Hurricane Irma. The phenomenon affected ten of Cuba's 15 provinces and caused significant damage in 53 of its municipalities (29.6%). During the response effort, the pre-established measures for the various phases (warning, alert and emergency) were deployed according to the disaster reduction plans for each level. In all provinces, animals were protected by moving them to safer locations, allowing for pre-established sanitary measures and technical assistance. Nonetheless, damage was incurred, mainly to the roofs of some animal housing. The following deaths were recorded: 210,150 poultry, 2,752 cattle (of which 73.8% were calves) and 866 pigs (of which 68% were young animals). In addition, 7% of the inventory of hives was damaged and 3.3% of hives were lost. Damage to infrastructure included: 466 poultry houses, 1,422 cattle houses, 431 pig houses, 1,200 wind pumps and 13 of the country's 17 feed concentrate plants. As no major damage was reported to the Veterinary Service's facilities (laboratories and offices), its viability was guaranteed at all times. Rapid damage assessment enabled priorities for rehabilitation and recovery actions to be set, with the result that, just three months after the hurricane had struck, 67% of the poultry houses and 33% of the pig houses had been restored. This article focuses on preparedness, response and lessons learned.


Asunto(s)
Tormentas Ciclónicas , Planificación en Desastres , Desastres , Animales , Bovinos , Cuba , Vivienda para Animales , Porcinos
9.
Zootaxa ; 4821(3): zootaxa.4821.3.3, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-33056311

RESUMEN

A new species, Cornigamasus allotritosternus sp. nov., is described based on the larva, protonymph, deutonymph and adult female and male collected from cow dung in Guizhou Province, China. The ontogenetic development of the gnathotectum, dorsal shields, ventral shields, and the chaetotaxy of the gnathosoma, idiosoma and legs are discussed and illustrated.


Asunto(s)
Ácaros , Animales , Bovinos , China , Femenino , Larva , Masculino , Sensilos
10.
PLoS One ; 15(8): e0228366, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32866142

RESUMEN

The role of questing ticks in the epidemiology of tick-borne diseases in Kenya's Maasai Mara National Reserve (MMNR), an ecosystem with intensified human-wildlife-livestock interactions, remains poorly understood. We surveyed the diversity of questing ticks, their blood-meal hosts, and tick-borne pathogens to understand potential effects on human and livestock health. By flagging and hand-picking from vegetation in 25 localities, we collected 1,465 host-seeking ticks, mostly Rhipicephalus and Amblyomma species identified by morphology and molecular analysis. We used PCR with high-resolution melting (HRM) analysis and sequencing to identify Anaplasma, Babesia, Coxiella, Ehrlichia, Rickettsia, and Theileria pathogens and blood-meal remnants in 231 tick pools. We detected blood-meals from humans, wildebeest, and African buffalo in Rh. appendiculatus, goat in Rh. evertsi, sheep in Am. gemma, and cattle in Am. variegatum. Rickettsia africae was detected in Am. gemma (MIR = 3.10) that had fed on sheep and in Am. variegatum (MIR = 250) that had fed on cattle. We found Rickettsia spp. in Am. gemma (MIR = 9.29) and Rh. evertsi (MIR = 200), Anaplasma ovis in Rh. appendiculatus (MIR = 0.89) and Rh. evertsi (MIR = 200), Anaplasma bovis in Rh. appendiculatus (MIR = 0.89), and Theileria parva in Rh. appendiculatus (MIR = 24). No Babesia, Ehrlichia, or Coxiella pathogens were detected. Unexpectedly, species-specific Coxiella sp. endosymbionts were detected in all tick genera (174/231 pools), which may affect tick physiology and vector competence. These findings show that ticks from the MMNR are infected with zoonotic R. africae and unclassified Rickettsia spp., demonstrating risk of African tick-bite fever and other spotted-fever group rickettsioses to locals and visitors. The protozoan pathogens identified may also pose risk to livestock production. The diverse vertebrate blood-meals of questing ticks in this ecosystem including humans, wildlife, and domestic animals, may amplify transmission of tick-borne zoonoses and livestock diseases.


Asunto(s)
Infestaciones por Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/epidemiología , Garrapatas/patogenicidad , Animales , Animales Salvajes , Babesia , Bovinos , Enfermedades de los Bovinos/microbiología , Coxiella , Ecosistema , Ehrlichia , Humanos , Ixodidae/microbiología , Kenia/epidemiología , Rhipicephalus , Rickettsia , Ovinos , Theileria , Infestaciones por Garrapatas/veterinaria , Enfermedades por Picaduras de Garrapatas/microbiología , Garrapatas/parasitología , Zoonosis
11.
PLoS One ; 15(8): e0231125, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32866172

RESUMEN

Korean peninsula weather is rapidly becoming subtropical due to global warming. In summer 2018, South Korea experienced the highest temperatures since the meteorological observations recorded in 1907. Heat stress has a negative effect on Holstein cows, the most popular breed of dairy cattle in South Korea, which is susceptible to heat. To examine physiological changes in dairy cows under heat stress conditions, we analyzed the profiles circulating microRNAs isolated from whole blood samples collected under heat stress and non-heat stress conditions using small RNA sequencing. We compared the expression profiles in lactating cows under heat stress and non-heat stress conditions to understand the regulation of biological processes in heat-stressed cows. Moreover, we measured several heat stress indicators, such as rectal temperature, milk yield, and average daily gain. All these assessments showed that pregnant cows were more susceptible to heat stress than non-pregnant cows. In addition, we found the differential expression of 11 miRNAs (bta-miR-19a, bta-miR-19b, bta-miR-30a-5p, and several from the bta-miR-2284 family) in both pregnant and non-pregnant cows under heat stress conditions. In target gene prediction and gene set enrichment analysis, these miRNAs were found to be associated with the cytoskeleton, cell junction, vasculogenesis, cell proliferation, ATP synthesis, oxidative stress, and immune responses involved in heat response. These miRNAs can be used as potential biomarkers for heat stress.


Asunto(s)
MicroARN Circulante/genética , Respuesta al Choque Térmico/genética , Lactancia/genética , Animales , Cruzamiento , Bovinos , Enfermedades de los Bovinos/genética , Femenino , Perfilación de la Expresión Génica/métodos , Trastornos de Estrés por Calor/sangre , Calor , MicroARNs/genética , Leche/metabolismo , Embarazo , ARN Circular/genética , República de Corea , Estaciones del Año , Análisis de Secuencia de ARN/métodos
12.
J Int Bioethique Ethique Sci ; 31(1): 31-42, 2020 09.
Artículo en Español | MEDLINE | ID: mdl-32988184

RESUMEN

Sin in its original form constitutes a deviation from human behavior. Christian doctrine incorporates into the Judeo-Christian tradition the deadly sins that we all know (and their demons), as well as the virtues that are supposed to defeat or at least neutralize: 1) pride / humility, 2) greed / generosity, 3) lust / chastity, 4) anger / patience, 5) gluttony / temperance, 6) envy / charity and 7) laziness / diligence. In this same line of thought, to sin would be to abuse the freedom of God. According to John Bossy, the seven deadly sins would be the expression of a social and community ethic with which the Catholic Church tried at the time to contain violence and heal the troubled medieval society. Sins and their penance were originally a healthy warning of how to manage one’s individual and social behavior (Savater, 2013). That which Modern society allows as lawful or not, has “overcome” the conduct and moral republicanism of our days (1). Morality is one of the most sophisticated features of human judgment, behavior, and mind. An individual who deviates from violent morality, rules and civil rights, even affecting the individual liberties of others, sometimes even aggressively. A scientific approach to the origins of evil refers us to the exciting analysis of the molecular, epigenetic, phylogenetic and cellular determinants of the neurobiology of sin. This formidable adventure of thought constitutes a harmonious path traveled by moral philosophy and the neurosciences of that long stretch that is between the error of Prometheus and the error of Descartes.


Asunto(s)
Catolicismo , Cristianismo , Principios Morales , Virtudes , Animales , Bovinos , Humanos , Filogenia
13.
Anim Sci J ; 91(1): e13456, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32926548

RESUMEN

In this study, we investigated whether bovine oviducts and endometria produce anti-Müllerian hormone (AMH) (for paracrine and autocrine signaling). Reverse transcription-polymerase chain reaction and western blotting detected AMH expression in oviductal and endometrial specimens. Immunohistochemistry revealed robust AMH expression in the ampulla and isthmus epithelia, and the glandular and luminal endometrial epithelia (caruncular endometria). AMH mRNA (measured by real-time PCR) and protein expression in these layers did not significantly differ among estrous phases in adult Japanese Black (JB) heifers (p > .1). Furthermore, the expression in these layers also did not differ among Holstein cows (93.8 ± 5.8 months old), JB heifers (25.5 ± 0.4 months old), and JB cows (97.9 ± 7.9 months old). We also compared AMH concentrations in the oviduct and uterine horn fluids among the three groups (measured by immunoassays). Interestingly, the AMH concentration in the oviduct fluid, but not in the uterine horn fluid, of Holstein cows was lower than those in JB heifers and cows (p < .05). Therefore, bovine oviducts and endometria express AMH and likely secrete it into the oviduct and uterine fluids.


Asunto(s)
Hormona Antimülleriana/genética , Hormona Antimülleriana/metabolismo , Endometrio/metabolismo , Células Epiteliales/metabolismo , Expresión Génica , Oviductos/metabolismo , Animales , Bovinos , Endometrio/citología , Ciclo Estral/metabolismo , Femenino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Útero/metabolismo
14.
Anim Sci J ; 91(1): e13451, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32926550

RESUMEN

This study assessed the effects of cryoprotectant concentration during equilibration on the efficiency of bovine blastocyst vitrification and the expression of selected developmentally important genes. In vitro produced bovine blastocysts were equilibrated in either 7.5% ethylene glycol (EG) + 7.5% DMSO (Va group) or in 2% EG + 2% DMSO (Vb group) then vitrified on Cryotop® sheets in 16.5% EG + 16.5% DMSO + 0.5M sucrose. After warming, embryos were cultured for 48 hr. Re-expansion, hatching, and the numbers of total and membrane damaged cells were compared among vitrified groups and a control. There was no significant difference between the vitrified groups in survival, cell numbers and the extent of membrane damage. Vitrification increased the number of membrane-damaged cells in both groups, however, in a greater extent in the Vb group. Vitrification increased (p < .05) the expression of the HSP70 gene in Va but not in Vb embryos. The expression of IGF2R, SNRPN, HDAC1, DNMT3B, BAX, OCT4, and IFN-t genes were the same in control and vitrified groups. In conclusion, the concentration of cryoprotectants during equilibration did not affect survival rates; however, normal cell numbers could be maintained only by equilibration in 15% cryoprotectants which was associated with increased HSP70 expression.


Asunto(s)
Blastocisto , Supervivencia Celular/efectos de los fármacos , Criopreservación/métodos , Criopreservación/veterinaria , Crioprotectores/farmacología , Fertilización In Vitro/métodos , Fertilización In Vitro/veterinaria , Vitrificación/efectos de los fármacos , Animales , Bovinos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Expresión Génica , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo
15.
Braz Dent J ; 31(4): 423-430, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32901720

RESUMEN

The aim of this study was to assess the effect of a newly developed nanocomplex formed of hydroxypropyl-b-cyclodextrin and 1% titanium tetrafluoride (TiF4) after distinct complexation periods (12/72 h) on demineralization of bovine enamel in vitro. Enamel blocks (n=60) were allocated in different groups: Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4, hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h of complexation and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation. The samples were evaluated by surface microhardness, cross-sectional microhardness and micro-CT. Scanning electron microscopy and energy dispersive X-ray spectrometry (SEM/EDX) were also obtained. Hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h complexation resulted in lower percentage of surface microhardness loss compared to Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4 and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation group, with a large effect size (from 1.307 to 2.943) and high power (84.9 to 99%). All groups resulted in similar integrated mineral loss (ΔZ) obtained by both internal microhardness and micro-CT techniques. Enamel treated with TiF4 and TiF4 + hydroxypropyl-b-cyclodextrin groups showed a TiO2 glaze-layer, while EDX evaluation identified Ti. The solution containing the inclusion complex of hydroxypropyl-b-cyclodextrin + TiF4 with 12 h of complexation period demonstrated a significant ability to reduce surface demineralization of sound enamel under an artificial cariogenic challenge.


Asunto(s)
Ciclodextrinas , Fluoruros , Animales , Bovinos , Estudios Transversales , Esmalte Dental , Titanio
16.
Med Lav ; 111(4): 321-325, 2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-32869768

RESUMEN

Although Bernardino Ramazzini is usually regarded only as the father of occupational medicine, his approach to fight the devastating rinderpest epidemic in 1711 is worth mentioning in the light of the public health emergency represented by Coronavirus Disease-2019 (COVID-19). This commentary (i) focuses on Ramazzini's xiii oration describing that event, (ii) analyses the approach suggested to fight the cattle epidemic and economic threats, (iii) highlights some similar aspects between the 1711 rinderpest epidemic and the current COVID-19 pandemic (team expertise, contagion transmissibility, drug treatment, preventive measures, decision timeliness).


Asunto(s)
Enfermedades de los Bovinos/historia , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Peste Bovina/historia , Animales , Betacoronavirus , Bovinos , Enfermedades de los Bovinos/virología , Historia del Siglo XVIII , Humanos , Pandemias , Salud Pública
17.
Anim Sci J ; 91(1): e13454, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32959464

RESUMEN

This study investigated the effects of substituting ear corn silage (ECS) for commercial formula feed on milk production and milk fatty acid profiles in grazing dairy farms during the summer season. A field survey was conducted on five grazing dairy farms in every summer month of 2017, 2018, and 2019. Three of the five farms substituted fresh ECS for the commercial formula feed at a ratio of 2:1 from July of each year (ECS farms). Other farms maintained the same feeding management as before (non-ECS farms). An interview survey was conducted on each farm to calculate feed intake and milk yield per cow. Feed and milk samples were collected in each survey. Milk compositions and milk fatty acid profiles were determined. The substitution of ECS for the commercial formula feed did not affect milk yield or milk composition, but ECS farms maintained low levels of milk urea compared with non-ECS farms (p < .01). The ECS substitution also influenced some of the milk fatty acid proportions; C16:0 and C16:1 increased, and trans-11 C18:1, cis-9,trans-11 C18:2, and the sum of polyunsaturated fatty acids decreased, while these fatty acid proportions were maintained in non-ECS farms throughout the summer season (p < .05).


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Bovinos/metabolismo , Bovinos/fisiología , Industria Lechera , Dieta/veterinaria , Suplementos Dietéticos , Ácidos Grasos/análisis , Herbivoria/fisiología , Lactancia/fisiología , Leche/metabolismo , Ensilaje , Zea mays , Animales , Femenino
18.
Nat Commun ; 11(1): 4654, 2020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32943640

RESUMEN

The shift from maternal to embryonic control is a critical developmental milestone in preimplantation development. Widespread transcriptomic and epigenetic remodeling facilitate this transition from terminally differentiated gametes to totipotent blastomeres, but the identity of transcription factors (TF) and genomic elements regulating embryonic genome activation (EGA) are poorly defined. The timing of EGA is species-specific, e.g., the timing of murine and human EGA differ significantly. To deepen our understanding of mammalian EGA, here we profile changes in open chromatin during bovine preimplantation development. Before EGA, open chromatin is enriched for maternal TF binding, similar to that observed in humans and mice. During EGA, homeobox factor binding becomes more prevalent and requires embryonic transcription. A cross-species comparison of open chromatin during preimplantation development reveals strong similarity in the regulatory circuitry underlying bovine and human EGA compared to mouse. Moreover, TFs associated with murine EGA are not enriched in cattle or humans, indicating that cattle may be a more informative model for human preimplantation development than mice.


Asunto(s)
Ensamble y Desensamble de Cromatina/fisiología , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Genoma , Animales , Blastómeros , Bovinos/embriología , Cromatina/metabolismo , Fertilización , Humanos , Ratones , Oocitos , Especificidad de la Especie , Factores de Transcripción/metabolismo
20.
Int J Oral Maxillofac Implants ; 35(5): 879-887, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32991637

RESUMEN

PURPOSE: To evaluate the influence on healing of the bony window elevated inward in the sinus cavity as a cortical bone graft. MATERIALS AND METHODS: Eighteen rabbits were included in the experiment. At the test sites (bony window), the antrostomy was prepared and the remaining bony window was elevated together with the sinus mucosa. At the control sites, the bony window was gently detached before the sinus mucosa elevation and discarded. The space obtained was grafted with deproteinized bovine bone mineral (DBBM). A collagen membrane was positioned on the antrostomy at both sides. The rabbits were euthanized after 2, 4, and 8 weeks in groups of six each. Histologic analyses in different regions of the elevated space were carried out, and a Wilcoxon test was used to estimate differences. Microcomputed tomography (microCT) analyses were also performed. RESULTS: After 2 weeks of healing, higher proportions of new bone were found in the test group compared with the control group due to the higher amount of bone formed in the region subjacent to the sinus mucosa. In this region, higher amounts of new bone were also found in the test group after 4 (P = .028) and 8 weeks of healing (P = .345). After 8 weeks of healing, the percentage of new bone was higher at the control sites compared with the test sites, with the proportions being 25.4% ± 3.2% and 21.3% ± 6.1%, respectively. In this period of evaluation, the bony window contributed with 20.1% ± 5.3% of vital bone in the test group. A fraction of 60.4% ± 10.8% of its surface was surrounded by new bone. In the microCT analysis, after 8 weeks of healing, fractions of 22.3% ± 1.6% and 22.2% ± 0.7% of bone were found in the test and control groups, respectively. CONCLUSION: The presence of the bony window positively influenced the healing in the elevated space, especially in the submucosa region. The bony window was vital and incorporated into newly formed bone.


Asunto(s)
Elevación del Piso del Seno Maxilar , Animales , Trasplante Óseo , Bovinos , Hueso Cortical/diagnóstico por imagen , Hueso Cortical/cirugía , Conejos , Cicatrización de Heridas , Microtomografía por Rayos X
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA