Thermorégulation des porcelets issus de deux lignées divergentes pour l’efficacité alimentaire

Hypothermia is a factor of piglet neonatal mortality. This study used Infra-Red Thermography (IRT) to assess thermoregulation abilities of piglets from two lines divergent for residual feed intake (RFI). Birth phenotypes (e.g. body weight, rectal temperature, physical measures, vitality test) were recorded from piglets selected for low RFI (more efficient; LRFI; n=34) or high RFI (less efficient; HRFI; n=28). The IRT images were taken at 8, 15, 30 and 60 min post-partum. Temperatures of the ear base and tip, and minimum, maximum and average temperatures of the back (i.e. shoulders to rumps) were extracted with Thermacam Researcher Pro 2.0 and analysed with linear mixed models. No difference in phenotypic data was detected between the two lines. All temperatures increased over time. Rectal temperature of piglets at birth was correlated with the initial temperature of the ear base and the maximum back temperature (0.36 and 0.35, respectively, P < 0.05). Overall, LRFI piglets, compared to HRFI piglets, had higher minimum (28.0 ± 0.2 °C vs 26.8 ± 0.2 °C, respectively, P < 0.001) and average (35.5 ± 0.2 °C vs 34.5 ± 0.1 °C, respectively, P < 0.001) back temperatures. Ear tip temperature decreased in HRFI piglets from 8 to 15 min post-partum, while it increased in LRFI piglets (-1.1 ± 0.4 °C vs 0.5 ± 0.5 °C, respectively, P < 0.05). In conclusion, IRT allowed non-invasive assessment of piglets’ thermoregulation abilities. Piglets selected for low RFI seemed to have better thermoregulation abilities at birth

Plasma 1H-NMR metabolic and amino acid profiles of newborn piglets from two lines divergently selected for residual feed intake

Abstract Together with environmental factors, physiological maturity at birth is a major determinant for neonatal survival and postnatal development in mammalian species. Maturity at birth is the outcome of complex mechanisms of intra-uterine development and maturation during the end of gestation. In pig production, piglet preweaning mortality averages 20% of the litter and thus, maturity is a major welfare and economic concern. Here, we used both targeted and untargeted metabolomic approaches to provide a deeper understanding of the maturity in a model of lines of pigs divergently selected on residual feed intake (RFI), previously shown to have contrasted signs of maturity at birth. Analyses were conducted on plasma metabolome of piglets at birth and integrated with other phenotypic characteristics associated to maturity. We confirmed proline and myo-inositol, previously described for their association with delayed growth, as potential markers of maturity. Urea cycle and energy metabolism were found more regulated in piglets from high and low RFI lines, respectively, suggesting a better thermoregulation ability for the low RFI (with higher feed efficiency) piglets

A 36,000-Year-Old Volcanic Eruption Depicted in the Chauvet-Pont d'Arc Cave (Ardèche, France)?

International audienceAmong the paintings and engravings found in the Chauvet-Pont d'Arc cave (Ardèche, France), several peculiar spray-shape signs have been previously described in the Megalo-ceros Gallery. Here we document the occurrence of strombolian volcanic activity located 35 km northwest of the cave, and visible from the hills above the cave entrance. The volcanic eruptions were dated, using 40 Ar/ 39 Ar, between 29 ± 10 ka and 35 ± 8 ka (2σ), which overlaps with the 14 C AMS and thermoluminescence ages of the first Aurignacian occupations of the cave in the Megaloceros Gallery. Our work provides the first evidence of an intense volcanic activity between 40 and 30 ka in the Bas-Vivarais region, and it is very likely that Humans living in the Ardèche river area witnessed one or several eruptions. We propose that the spray-shape signs found in the Chauvet-Pont d'Arc cave could be the oldest known depiction of a volcanic eruption, predating by more than 34 ka the description by Pliny the Younger of the Vesuvius eruption (AD 79) and by 28 ka the Çatalhöyük mural discovered in central Turkey

The Chauvet-Pont d’Arc cave and the Bas-Vivarais volcanic field.

<p>(A) Digital elevation model of France (Courtesy NASA/JPL-Caltech) showing the MIS 2–3 active volcanoes and the Chauvet-Pont d’Arc cave; C.P: Chaîne de Puys; B.V: Bas-Vivarais. (B) Digital elevation model of the Bas-Vivarais and Ardèche (Courtesy NASA/JPL-Caltech). The volcanic centers investigated are highlighted in bold italic fonts. (C) Detail of the spray-shape sign engraving from the Megaloceros panel. (D) View from the plateau above the Chauvet-Pont d’Arc cave showing several strombolian cones located 35 km Northwest (Courtesy NASA/JPL-Caltech).</p

Plateau spectra for the three volcanic centers dated.

<p>Uncertainties are given at the 2σ level. Plateau steps are plotted at the 1σ level.</p

Example of a spray-shape sign from Chauvet-Pont d’Arc cave compared to the oldest known depictions of volcanic eruptions.

<p>(A) Map of the Chauvet-Pont d’Arc cave. (B) General view of the Megaloceros panel. The green dot marks the location of the ¹⁴C AMS date [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref008" target="_blank">8</a>] (picture credit D. Genty). (C) Detail of the Megaloceros panel chronological succession [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref008" target="_blank">8</a>] (pictures credit V. Feruglio-D. Baffier). (D) Petroglyphs depicting the Porak volcano eruption and dated from the 5^th millennium BC in the Syunik region of Armenia [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref003" target="_blank">3</a>]. The figure is similar to [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref003" target="_blank">3</a>] but not identical to the original image, and is therefore for illustrative purposes only. (E) Çatalhöyük mural painting (Turkey) considered the oldest depiction of a volcanic eruption dated from the 8^th/7^th millennium BC [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref001" target="_blank">1</a>].</p

Volcanic centers ⁴⁰Ar/³⁹Ar ages and spray-shape sign TL and ¹⁴C AMS dates.

<p>In red: ⁴⁰Ar/³⁹Ar ages of the three volcanic centers studied; blue: TL age on reddened limestone in the Megaloceros Gallery [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref026" target="_blank">26</a>]; ¹⁴C AMS dates correspond to the first occupation of the Megaloceros Gallery in the Chauvet-Pont d’Arc cave [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref005" target="_blank">5</a>]. The ¹⁴C AMS in green corresponds to the date obtained for the sample taken from the rump of the Megaloceros [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref008" target="_blank">8</a>]. Uncertainties are reported at the 2σ level excluding TL age where uncertainty is an estimated standard deviation [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146621#pone.0146621.ref026" target="_blank">26</a>].</p