The impact of hair coat color on longevity of Holstein cows in the tropics

Abstract Background Use of cannabidiol (CBD), the primary non-psychoactive compound found in cannabis, has recently risen dramatically, while relatively little is known about the underlying molecular mechanisms of its effects. Previous work indicates that direct CBD exposure strongly impacts the brain, with anxiolytic, antidepressant, antipsychotic, and other effects being observed in animal and human studies. The epigenome, particularly DNA methylation, is responsive to environmental input and can direct persistent patterns of gene regulation impacting phenotype. Epigenetic perturbation is particularly impactful during embryogenesis, when exogenous exposures can disrupt critical resetting of epigenetic marks and impart phenotypic effects lasting into adulthood. The impact of prenatal CBD exposure has not been evaluated; however, studies using the psychomimetic cannabinoid Δ9-tetrahydrocannabinol (THC) have identified detrimental effects on psychological outcomes in developmentally exposed adult offspring. We hypothesized that developmental CBD exposure would have similar negative effects on behavior mediated in part by the epigenome. Nulliparous female wild-type Agouti viable yellow (Avy) mice were exposed to 20 mg/kg CBD or vehicle daily from two weeks prior to mating through gestation and lactation. Coat color shifts, a readout of DNA methylation at the Agouti locus in this strain, were measured in F1 Avy/a offspring. Young adult F1 a/a offspring were then subjected to tests of working spatial memory and anxiety/compulsive behavior. Reduced-representation bisulfite sequencing was performed on both F0 and F1 cerebral cortex and F1 hippocampus to identify genome-wide changes in DNA methylation for direct and developmental exposure, respectively. Results F1 offspring exposed to CBD during development exhibited increased anxiety and improved memory behavior in a sex-specific manner. Further, while no significant coat color shift was observed in Avy/a offspring, thousands of differentially methylated loci (DMLs) were identified in both brain regions with functional enrichment for neurogenesis, substance use phenotypes, and other psychologically relevant terms. Conclusions These findings demonstrate for the first time that despite positive effects of direct exposure, developmental CBD is associated with mixed behavioral outcomes and perturbation of the brain epigenome.

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Evaluating the role of contracting and expanding rainforest in initiating cycles of speciation across the Isthmus of Panama

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.0706 ◽

2012 ◽

Vol 279 (1742) ◽

pp. 3520-3526 ◽

Cited By ~ 37

Author(s):

Brian Tilston Smith ◽

Amei Amei ◽

John Klicka

Keyword(s):

Bird Species ◽

Tropical Regions ◽

Isthmus Of Panama ◽

Species Pairs ◽

The Matrix ◽

High Species Richness ◽

The Rich ◽

The Tropics ◽

The Impact

Climatic and geological changes across time are presumed to have shaped the rich biodiversity of tropical regions. However, the impact climatic drying and subsequent tropical rainforest contraction had on speciation has been controversial because of inconsistent palaeoecological and genetic data. Despite the strong interest in examining the role of climatic change on speciation in the Neotropics there has been few comparative studies, particularly, those that include non-rainforest taxa. We used bird species that inhabit humid or dry habitats that dispersed across the Panamanian Isthmus to characterize temporal and spatial patterns of speciation across this barrier. Here, we show that these two assemblages of birds exhibit temporally different speciation time patterns that supports multiple cycles of speciation. Evidence for these cycles is further corroborated by the finding that both assemblages consist of ‘young’ and ‘old’ species, despite dry habitat species pairs being geographically more distant than pairs of humid habitat species. The matrix of humid and dry habitats in the tropics not only allows for the maintenance of high species richness, but additionally this study suggests that these environments may have promoted speciation. We conclude that differentially expanding and contracting distributions of dry and humid habitats was probably an important contributor to speciation in the tropics.

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Evaluating the impact of breed, pregnancy, and hair coat on body temperature and sweating rate of hair sheep ewes in the tropics1

Journal of Animal Science ◽

10.2527/jas.2016.1125 ◽

2017 ◽

Vol 95 (7) ◽

pp. 2936-2942 ◽

Cited By ~ 2

Author(s):

R. W. Godfrey ◽

W. D. Preston ◽

S. R. Joseph ◽

L. LaPlace ◽

P. E. Hillman ◽

...

Keyword(s):

Body Temperature ◽

Sweating Rate ◽

Hair Sheep ◽

Hair Coat ◽

The Impact

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On what scales can GOSAT flux inversions constrain anomalies in terrestrial ecosystems?

10.5194/acp-2018-909 ◽

2019 ◽

Author(s):

Brendan Byrne ◽

Dylan B. A. Jones ◽

Kimberly Strong ◽

Saroja M. Polavarapu ◽

Anna B. Harper ◽

...

Keyword(s):

Spatial Scales ◽

Net Ecosystem Exchange ◽

Terrestrial Ecosystems ◽

Atmospheric Co2 ◽

Strong Correlations ◽

Climate Anomalies ◽

Temperature And Precipitation ◽

The Tropics ◽

Emergent Constraint ◽

The Impact

Abstract. Interannual variations in temperature and precipitation impact the carbon balance of terrestrial ecosystems, leaving an imprint in atmospheric CO2. Quantifying the impact of climate anomalies on the net ecosystem exchange (NEE) of terrestrial ecosystems can provide a constraint to evaluate terrestrial biosphere models against, and may provide an emergent constraint on the response of terrestrial ecosystems to climate change. We investigate the spatial scales over which interannual variability in NEE can be constrained using atmospheric CO2 observations from the Greenhouse Gases Observing Satellite (GOSAT). NEE anomalies are calculated by performing a series of inversion analyses using the GEOS-Chem model to assimilate GOSAT observations. Monthly NEE anomalies are compared to proxies, variables which are associated with anomalies in the terrestrial carbon cycle, and to upscaled NEE estimates from FLUXCOM. Strong agreement is found in the timing of anomalies in the GOSAT flux inversions with soil temperature and FLUXCOM. Strong correlations are obtained (P RNINO3.4) in the tropics on continental and larger scales, and in the northern extratropics on sub-continental scales during the summer (R2 ≥ 0.49). These results, in addition to a series of observing system simulation experiments that were conducted, provide evidence that GOSAT flux inversions can isolate anomalies in NEE on continental and larger scales. However, in both the tropics and northern extratropics, the agreement between the inversions and the proxies/FLUXCOM is sensitive to the flux inversion configuration. Our results suggest that regional scales are likely the minimum scales that can be resolved in the tropics using GOSAT observations, but obtaining robust NEE anomaly estimates on these scales may be difficult.

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Effective thermal conductivity of the hair coat of Holstein cows in a tropical environment

Revista Brasileira de Zootecnia ◽

10.1590/s1516-35982009001100022 ◽

2009 ◽

Vol 38 (11) ◽

pp. 2218-2223 ◽

Cited By ~ 11

Author(s):

Alex Sandro Campos Maia ◽

Roberto Gomes da Silva ◽

João Batista Freire de Souza Junior ◽

Rosiane Batista da Silva ◽

Hérica Girlane Tertulino Domingos

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Free Convection ◽

Effective Thermal Conductivity ◽

Tropical Environment ◽

Holstein Cows ◽

Hair Coat ◽

Black And White ◽

Low K

The objective of the present study was to assess the effective thermal conductivity of the hair coat (k ef, mW.m-1.K-1) of Holstein cows in a tropical environment, as related to conduction and radiation in the absence of free convection. The average k ef was 49.72 mW.m-1.K-1, about twice the conductivity of the air (26 mW.m-1.K-1) and much less than that of the hair fibres (260 mW.m-1.K-1). The low k ef values were attributed mainly to the small cross area of individual hairs, ρef/ρf (17.2% and 21.3% for black and white hairs, respectively). White coats were denser, with longer hairs and significantly higher k ef (53.15 mW.m-1.K-1) than that of the black hairs (49.25 mW.m-1.K-1). The heritability coefficient of the effective thermal conductivity was calculated as h²=0.18 the possibility was discussed of selecting cattle for increased heat transfer through the hair coat.

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Land–atmosphere interactions in the tropics

10.5194/hess-2019-12 ◽

2019 ◽

Author(s):

Pierre Gentine ◽

Adam Massmann ◽

Benjamin R. Lintner ◽

Sayed Hamed Alemohammad ◽

Rong Fu ◽

...

Keyword(s):

Land Surface ◽

Deep Convection ◽

Lower Troposphere ◽

Surface Fluxes ◽

Surface Radiation ◽

Spatial And Temporal Scales ◽

Wide Range ◽

Shallow Clouds ◽

The Tropics ◽

The Impact

Abstract. The continental tropics play a leading role in the terrestrial water and carbon cycles. Land–atmosphere interactions are integral in the regulation of surface energy, water and carbon fluxes across multiple spatial and temporal scales over tropical continents. We review here some of the important characteristics of tropical continental climates and how land–atmosphere interactions regulate them. Along with a wide range of climates, the tropics manifest a diverse array of land–atmosphere interactions. Broadly speaking, in tropical rainforests, light and energy are typically more limiting than precipitation and water supply for photosynthesis and evapotranspiration; whereas in savanna and semi-arid regions water is the critical regulator of surface fluxes and land–atmosphere interactions. We discuss the impact of the land surface, how it affects shallow clouds and how these clouds can feedback to the surface by modulating surface radiation. Some results from recent research suggest that shallow clouds may be especially critical to land–atmosphere interactions as these regulate the energy budget and moisture transport to the lower troposphere, which in turn affects deep convection. On the other hand, the impact of land surface conditions on deep convection appear to occur over larger, non-local, scales and might be critically affected by transitional regions between the climatologically dry and wet tropics.

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Seasonal impact of biogenic VSL bromine on the evolution of mid-latitude lowermost stratospheric ozone during the 21<sup>st</sup> century

10.5194/acp-2019-1091 ◽

2020 ◽

Author(s):

Javer A. Barrera ◽

Rafael P. Fernandez ◽

Fernando Iglesias-Suarez ◽

Carlos A. Cuevas ◽

Jean-Francois Lamarque ◽

...

Keyword(s):

21St Century ◽

Total Ozone ◽

Stratospheric Ozone ◽

Polar Regions ◽

Total Ozone Column ◽

Seasonal Impact ◽

The Tropics ◽

The Impact ◽

Ozone Column ◽

Modelling Study

Abstract. Biogenic very short-lived bromine (VSLBr) represents, nowadays, ~ 25 % of the total stratospheric bromine loading. Owing to their much shorter lifetime compared to anthropogenic long-lived bromine (LLBr, e.g., halons) and chlorine (LLCl, e.g., chlorofluorocarbons) substances, the impact of VSLBr on ozone peaks at the extratropical lowermost stratosphere, a key climatic and radiative atmospheric region. Here we present a modelling study of the evolution of stratospheric ozone and its chemical losses in extra-polar regions during the 21st century, under two different scenarios: considering and neglecting the additional stratospheric injection of 5 ppt biogenic VSLBr naturally released from the ocean. Our analysis shows that the inclusion of VSLBr result in a realistic stratospheric bromine loading and improves the quantitative 1980–2015 model-satellite agreement of total ozone column (TOC) in the mid-latitudes. We show that the overall ozone response to VSLBr within the mid-latitudes follows the stratospheric abundances evolution of long-lived inorganic chlorine and bromine throughout the 21st century. Additional ozone losses due to VSLBr are maximised during the present-day period (1990–2010), with TOC differences of −8 DU (−3 %) and −5.5 DU (−2 %) for the southern (SH-ML) and northern (NH-ML) mid-latitudes, respectively. Moreover, the projected TOC differences at the end of the 21st century are at least half of the values found for the present-day period. In the tropics, a small (

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