Desempenho produtivo e características quantitativas da carcaça de cordeiros alimentados com silagem de sorgo sacarino

The objective of this work was to evaluate the productive performance and carcass traits of lambs fed silages of different types of sorghum and corn. Thirty-two uncastrated male Suffolk lambs were used. The experimental design was completely randomized, with four treatments (silages) and eight replicates (animals). Silages of the GrandSilo forage sorghum, BRS 506 saccharine sorghum, BRS 511 saccharine sorghum, and the BRS 2223 double-grain corn hybrid were tested. The lambs fed sorghum silages had a lower daily dry matter intake than those fed corn silage. The diet containing corn silage led to 27% greater weight gain, when compared with the treatments with the other silages. In vivo digestibility did not differ among the different silages. Lambs fed corn silage showed the lowest hot and cold carcass yields of 44.71 and 42.62%, respectively, whereas those that consumed BRS 506 sorghum silage showed the highest hot and cold carcass yields of 46.90 and 44.78%. The greater intake by and the better performance of the animals fed corn silage was not enough to enhance production and carcass yield. Lambs fed BRS 506 saccharine sorghum silage have higher efficiency in the conversion of silage into carcass.O objetivo deste trabalho foi avaliar o desempenho produtivo e as características da carcaça de cordeiros alimentados com silagens de diferentes tipos de sorgo e milho. Foram utilizados 32 cordeiros machos, da raça Suffolk. O delineamento experimental foi inteiramente casualizado, com quatro tratamentos (silagens) e oito repetições (animais). Foram testadas silagens de sorgo forrageiro GrandSilo, sorgo sacarino BRS 506, sorgo sacarino BRS 511 e milho híbrido duplo BRS 2223. Os cordeiros alimentados com silagens de sorgo apresentaram menor consumo diário de matéria seca que os alimentados com silagem de milho. A dieta contendo silagem de milho proporcionou ganho de peso 27% superior ao dos tratamentos com as demais silagens. A digestibilidade in vivo não diferiu entre as diferentes silagens. Os cordeiros alimentados com silagem de milho apresentaram os menores rendimentos de carcaça quente e fria, de 44,71 e 42,62%, respectivamente, enquanto os que consumiram silagem de sorgo BRS 506 apresentaram os maiores rendimentos de carcaça quente e fria, de 46,90 e 44,78%. O maior consumo e o melhor desempenho dos animais alimentados com silagem de milho não foi suficiente para incrementar a produção e o rendimento de carcaça. Os cordeiros alimentados com silagem de sorgo sacarino BRS 506 apresentam maior eficiência de conversão da silagem em carcaça

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Different intervals of behavioral observation in the scanning method and the real behavior of pigs

ABSTRACT The objective of this work was to study the behavior of swine females in the grower phase using different observation intervals (continuous, 5, and 10 min). A total of 42 swine were used, 14 of them for each treatment, which were identified with a marker stick. These animals were observed using the focal sampling method for 5 h. The treatments were the observation intervals: continuous, every 5 min, and every 10 min. Among the behaviors analyzed during the experiment, the different observation intervals did not affect the estimated time spent in the activities. Time observation intervals of 10 min or less adequately describe the duration of the main behavioral parameters of female pigs in this setting

Nano-sized zeolites as modulators of thiacloprid toxicity on Chironomus riparius

This study investigated whether zeolites of different size (Y30 (nano-sized) and H-Beta(OH)-III (forming large aggregates/agglomerates composed of 50 nm small primary particles)) exerted acute toxicity on larvae of the non-biting midge, Chironomus riparius, and whether such zeolites are able to modulate the toxicity of a common insecticide, thiacloprid, by means of adsorption of a dissolved toxicant. We conducted acute toxicity tests with fourth instar larvae of C. riparius. In these tests, larvae were exposed to zeolites or thiacloprid solely, or to mixtures of both compounds. The mixtures comprised 1.0 µg/L thiacloprid in addition to low (5.2 mg/L), medium (18.2 mg/L), and high (391.7 mg/L) zeolite concentrations, resulting in different adsorption rates of thiacloprid. As biological endpoints, changes in mortality rates and in behavior were monitored every 24 h over a total investigation period of 96 h. Furthermore, we conducted chemical analyses of thiacloprid in the medium and the larvae and located the zeolite particles within the larvae by LA-ICP-MS imaging techniques. Our results demonstrate that both types of zeolites did not exert acute toxicity when applied as single-substances, but led to reduced acute toxicity of thiacloprid when applied together with thiacloprid. These results are in line with the sorption properties of zeolites indicating reduced bioavailability of thiacloprid, although our data indicate that thiacloprid can desorb from zeolites to some extent. While freely dissolved (i.e., non-sorbed) fraction of thiacloprid was a good parameter to roughly estimate toxic effects, it did not correlate with measured internal thiacloprid concentrations. Moreover, it was shown that both zeolite types were ingested by the larvae, but no indication for cellular uptake of them was found

Correction: Nano-sized Al2O3 reduces acute toxic effects of thiacloprid on the non-biting midge Chironomus riparius.

[This corrects the article DOI: 10.1371/journal.pone.0176356.]

The use of crude glycerin as an alternative to reduce fermentation losses and enhance the nutritional value of Piatã grass silage

ABSTRACT The objective of this study was to evaluate fermentation losses and the nutritional value of silage of Brachiaria brizantha cv BRS Piatã ensiled with different levels of crude glycerin. The experiment followed a 4 × 2 completely randomized factorial design with four doses of crude glycerin (0, 100, 200, and 300 g kg–1 of DM silage) and two cutting ages (45 and 60 days) with four replicates per treatment (silos). The parameters of dry matter losses, effluents losses, gas losses, pH, microbial population, and nutritional value of the silage were evaluated. There was no difference in pH among the tested doses of crude glycerin. However, reductions in dry matter and gas losses were observed as a function of crude glycerin doses. Bacterial populations of lactic acid and facultative mesophilic anaerobes also increased as a function of crude glycerin inclusion. Crude glycerin increased ether extract levels and reduced neutral detergent fiber and acid detergent fiber concentrations (dilution effect), improving chemical composition of the silage. Crude glycerin can be used in the ensiling of Piatã grass and the dose of 300 g kg–1 of DM yields the best results

Mortality rates (means ± SD) of larvae per test vessel.

<p>Larvae were exposed to either thiacloprid solely, a mixture of thiacloprid and 300 mg/L nano-Al₂O₃, or a mixture of 1000 mg/L nano-Al₂O_3, after 96 h of exposure (n = 12). Four comparisons (Likelihood ratio test and Fishers exact test, if necessary) were conducted (one for each thiacloprid concentration) and significant differences between the data displayed at the respective two ends of the horizontal lines are given (* p ≤ α when adjusted according to Holm-Bonferroni’s method [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0176356#pone.0176356.ref023" target="_blank">23</a>], Fishers exact test). Nominal values are shown in this graph, whereas measured concentrations can be obtained from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0176356#pone.0176356.t001" target="_blank">Table 1</a>.</p