Effect of Different Finishing Strategies and Steer Temperament on Animal Welfare and Instrumental Meat Tenderness

The aim of this experiment was to evaluate the effect of different fattening systems from pasture to concentrate and temperament on animal welfare (AW) and meat quality (MQ). Eighty-four Hereford steers were randomly assigned to the following groups: T1, pasture (4% of animal live weight: LW); T2, pasture (3% LW) plus concentrate (0.6% LW); T3, pasture (3% LW) plus concentrate (1.2% LW); T4, an ad libitum concentrate treatment. Temperament was assessed by three individual tests: crush score, flight time, and exit speed, building a multicriterial temperament index (TIndex). The flight zone was also registered for each treatment. AW was assessed through the integration of indicators of productivity, physiology, and behavior, as well as by monitoring the health status within each treatment. Shear force was registered for MQ. Differences in average daily gain were due to the different energetic composition of the diets (T4 > T3 > T2 > T1) and were not attributable to animal welfare problems. Animals from T4 had the higher average daily gain (ADG) but welfare was negatively affected, being evident through physiological indicators, the restriction or deprivation of relevant behaviors, diet-related diseases, and mortality. T1, T2, and T3 did not appear to compromise animal welfare. However, strict preventive measures and monitoring should be taken during the habituation process and when using any new diet that includes concentrate, because of possible dietary diseases. Shear force values were lower in T1. None of the animals in our experiment were excitable or aggressive, but there was a positive response to handling in all treatments. In addition, regardless of diet, calmer animals had higher average daily gain and lower shear force values; thus, temperament appears to have a significant influence on productivity and meat quality.

TYPES AND FORMS OF ENERGY IN THE PERFORMANCE TEXT OF A MUSICAL WORK

In this article, for the first time in musicology, a classification of the types and forms of energy that exist in music is given. The latter are not indicated in the musical text, but are hidden in the energetic composition of the musical work and reveal themselves in the text of the musician-performer who re-creates the musical work, recreating the primary fire that gave it birth.

On the significance of relativistically hot pairs in the jets of FR II radio galaxies

ABSTRACT The energetic composition of radio lobes in the FR II galaxies – estimated by comparing their radio luminosities with the powers required to inflate cavities in the external medium – seems to exclude the possibility of their energetic domination by protons. Furthermore, if the jets were dominated by the kinetic energy of cold protons, it would be difficult to efficiently accelerate leptons in the jets’ terminal shocks. Assuming that the relative energy contents of leptons, protons, and magnetic fields are preserved across the shocks, the above implies that the large-scale jets should also be energetically dominated by leptons: Pe,j ≳ Pp,j. On the other hand, previous studies of small-scale jets in blazars and radio cores suggest a pair content (number of electrons and positrons per proton) of the order of ne/np ∼ 20. Assuming further that the particle composition of jets does not evolve beyond the blazar scales, we show that this implies an average random Lorentz factor of leptons in large-scale jets of $\bar{\gamma }_{\rm e,j} \gtrsim 70(1+\chi _{\rm p})(20n_{\rm p}/n_{\rm e})$, and that the protons should be mildly relativistic with χp ≡ (ϵp + pp)/ρpc2 ≲ 2, pp the pressure of protons, ϵp the internal energy density of protons, and ρpc2 the rest-mass energy density of protons. We derive the necessary conditions for loading the inner jets by electron–positron pairs and proton–electron plasma, and provide arguments that heating of leptons in jets is dominated by magnetic reconnection.

Arctic seabirds and shrinking sea ice: egg analyses reveal the importance of ice-derived resources

In the Arctic, sea-ice plays a central role in the functioning of marine food webs and its rapid shrinking has large effects on the biota. It is thus crucial to assess the importance of sea-ice and ice-derived resources to Arctic marine species. Here, we used a multi-biomarker approach combining Highly Branched Isoprenoids (HBIs) with δ13C and δ15N to evaluate how much Arctic seabirds rely on sea-ice derived resources during the pre-laying period, and if changes in sea-ice extent and duration affect their investment in reproduction. Eggs of thick-billed murres (Uria lomvia) and northern fulmars (Fulmarus glacialis) were collected in the Canadian Arctic during four years of highly contrasting ice conditions, and analysed for HBIs, isotopic (carbon and nitrogen) and energetic composition. Murres heavily relied on ice-associated prey, and sea-ice was beneficial for this species which produced larger and more energy-dense eggs during icier years. In contrast, fulmars did not exhibit any clear association with sympagic communities and were not impacted by changes in sea ice. Murres, like other species more constrained in their response to sea-ice variations, therefore appear more sensitive to changes and may become the losers of future climate shifts in the Arctic, unlike more resilient species such as fulmars.

EQUATIONS TO PREDICT THE METABOLIZABLE ENERGY OF MEAT AND BONE MEAL FOR GROWING PIGS

ABSTRACT The prediction of metabolizable energy (ME) of meat and bone meal (MBM) for pigs is an interesting tool, however, used models to predict these values must be validated in order to garantee higher precision. The aim of this study was to determine the chemical and energetic composition of different types of MBM for pigs and to adjust and validate models to better predict the ME based on the chemical composition. Thirty-two barrows, averaging an initial weight of 26.75 ± 1.45 kg, were individually allotted in a randomized block design with eight treatments and four replicates. The treatments consisted of seven types of MBM that replaced 20% of the basal diet. A stepwise procedure was the statistical procedure used to adjust the prediction equations and the ME was the dependent parameter. The validation of the adjusted models was performed using an independent databank of chemical and energetic composition of theBrazilian and international MBM. The metabolizable energy of different meat and bone meals ranged from 1645 to 2645 kcal kg-1. The equations that provide a good prediction of metabolizable energy of meat and bone meal for swine in Brazil are EM1 = -4233.58 + 0.4134GE + 72CP + 89.62ash - 159.06Ca; EM2 = 2087.49 + 0.3446GE + 31.82ash - 189.18Ca; EM3 = 2140.13 + 0.3845GE - 112.33Ca; EM4 = -346.58 + 0.656GE; EM5 = 3221.27 + 178.96fat - 76.55ash; and EM6 = 5356.45 - 84.75ash.