Calculation of selection indexes that includes highly correlated traits

International audienc

Value of early weight measurements as predictors of body weight at later ages in reindeer

Phenotypic variances in live weight in a reindeer population and repeatabilities of the weights were estimated. The population consisted of 1847 and 1878 unselected male and female calves respectively, for which data from weighings at 2 and 7 months of age were available. All individuals in a selected population, consisting of 469 of the heaviest females, were weighed at 2, 7 and 19 months of age. The data were colleted during four successive years, 1986 - 1989. An indirect selection model for improving female weight at 19 months of age was proposed. Variance in the unselected population was higher between animals than within animals. Repeatability was estimated to be 0.636 for the male calves and 0.609 for the female calves. In the selected population, within-individual variance was higher than between-animal variance. Repeatabilities were, after correction for the effect of selection, 0.316 (between 2 and 19 months) and 0.548 (between 7 and 19 months). The aim of the selection model was to increase the average weight in the primiparous group to improve their calf production ability. Using the model, the number of animals weighing equal to or more than a certain threshold weight and the number needed for recruitment at 19 months of age could be determined

Causes of variation in growth rate of reindeer calves

Weights of individual reindeer calves were registered on 3 or 4 occasions from the July roundup to the last slaughter roundup in January during each of four consecutive years (1986 to 1989). The observations were made in a tagged herd located in the southern part of the reindeer area in Sweden (63°N, 12°E). A total of 10 400 live-weight measurements were made, and the relationship between pre-slaughter weight and carcass weight was estimated using data from 109 individuals. Variation in weight and weight gain between weighing occasions was related to sex, number of days in the corral, scale and year. Non-linear growth curves were fit to the adjusted weights. For each sex, smoothed average weights and dispersions, both within and between year, as well as the coefficient of variation were calculated from data generated from the estimated functions. Individual calf weights were shown to be influenced by sex, weighing day within occasion, and by year. Reindeer calves gained between 20 and 25 kg in live body weight from two to 6-8 months of age. Male calves were heavier than female calves over the whole period and they gained in live weight on average 10 g/day more than female calves. Between year coefficient of variation was between 1.5 and 7% with the largest variation between years for July and January weights and the lowest variation for September weights. The growth curves showed that the major increase in weight was between July and September. From September to December/January the additional increase was only 5%. Dressing-percentage was influenced by live weight prior to slaughter. A positive relationship between live weight and dressing percentage was shown

Combined index for milk production and growth rate as selection criteria of performance tested AI bulls

International audienc

Health, body condition and blood metabolites in reindeer after submaintenance feed intake and subsequent feeding

The transition from experimentally induced poor nutritional conditions to feeding was studied with 69 eight-month-old female reindeer (Rangifer tarandus tarandus). During a pre-experimental period, all reindeer were fed a simulated winter diet with 80% lichens Cladina spp. and 20% Vaccinum myrtillus shrubs and Salix spp. leaves (lichen diet) ad lib. The reindeer were divided into five groups. A control group (group C) was fed the lichen diet ad lib. throughout the experiment. Four groups were fed half of that ration for eight days and were then totally deprived of feed for one day (restriction period). During the following 34 days (feeding period) the groups were re-fed the lichen diet (group L), fed pelleted reindeer feed combined with either lichen (group PL) or grass silage (group PS), or fed silage with a gradually increasing addition of pellets (group SP). Weekly measurements of blood samples and body weighr showed that the control group remained clinically healthy and had stable blood plasma concentrations of protein, urea, glucose and insulin throughout the experiment, but they lost weight. At slaughter, before and after the restriction period, all animals had lost rumen-free body weight, but the reindeer fed a restricted amount of feed lost more than the control group. Also the plasma metabolites were affected by the restricted feeding, with increased concentrations of urea and decreased concentrations of glucose. Group L responded immediately to the ad lib. feeding with blood metabolite levels rapidly approaching those of group C. The body weight developments were similar in groups L and C. Although the feed rations were increased gradually, diarrhoea occurred in some animals belonging to groups PL and PS within the first week of the feeding period. All reindeer recovered, after antibiotic treatment of the worst affected animals. The PL and PS groups, which had high contents of metabolisable energy and crude protein in their diets, showed increased con-centtations of plasma protein, urea and insulin. At the end of the feeding period, these groups had increased their body and carcass weights and gained fat, whereas reindeer fed the lichen diet had lost weight. Severe health problems (malnutrition and so-called wet belly) occurred in group SP during the first weeks of feeding and led to loss of animals, and consequently the SP group was excluded from the remainder of rhe experiment. The general conclusion is that the lichen diet did not cause any digestive problems, but resulted in a continuous decline in body weight and small or deficient fat reserves. After the initial diarrhoea, feeding with diets comprising pellets from the start resulted in improved condition, expressed as increased body weight, fat gain and higher concentrations of plasma protein, urea and insulin in relation to the control group. The diet initially based on grass in the form of silage of the given quality seemed insufficient as feed to reindeer calves in a poor nutritional state

In Situ Detection of Organic Molecules on the Martian Surface With the Mars Organic Molecule Analyzer (MOMA) on Exomars 2018

The Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars rover will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from radiative and oxidative degradation. The MOMA instrument is centered around a miniaturized linear ion trap (LIT) that facilitates two modes of operation: i) pyrolysisgas chromatography mass spectrometry (pyrGC-MS); and, ii) laser desorptionionization mass spectrometry (LDI-MS) at ambient Mars pressures. The LIT also enables the structural characterization of complex molecules via complementary analytical capabilities, such as multi-frequency waveforms (i.e., SWIFT) and tandem mass spectrometry (MSMS). When combined with the complement of instruments in the rovers Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds

Performance of the Linear Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer (MOMA) Investigation on the 2018 Exomars Rover

The 2018 ExoMars rover mission includes the Mars Organic Molecule Analyzer (MOMA) investigation. MOMA will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from degradation derived from cosmic radiation and/or oxidative chemical reactions. When combined with the complement of instruments in the rover's Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds. The MOMA investigation is led by the Max Planck Institute for Solar System Research (MPS) with the mass spectrometer subsystem provided by NASA GSFC. MOMA's linear ion trap mass spectrometer (ITMS) is designed to analyze molecular composition of: (i) gas evolved from pyrolyzed powder samples and separated in a gas chromatograph; and, (ii) ions directly desorbed from crushed solid samples at Mars ambient pressure, as enabled by a pulsed UV laser system, fast-actuating aperture valve and capillary ion inlet. Breadboard ITMS and associated electronics have been advanced to high end-to-end fidelity in preparation for flight hardware delivery to Germany in 2015

Underestimated role of legume roots for soil N fertility

Research ArticleNitrogen (N) is a major fertilizing element for plants. The distribution of N in legumes is influencing the efficiency of the next crop. Nitrogen storage in legumes is actually estimated by N fixation in shoots, whereas there is little knowledge on the contribution of roots and nodules to legume N and soil N. Here, we studied the contribution of roots and nodules of grain and pasture legumes to plant N and soil N in Mediterranean fields. Experiments were run under rainfed conditions for a 2-year period in three regions of Portugal. Entire plants including top plant and visible roots and nodules were sampled at the end of the growing seasons for grain legumes, sweet and yellow lupine, and over two harvests in case of pastures. N2 fixation was measured for grain legumes and pasture legumes using 15N tracing. Our results show that aboveground N concentration did not vary among legumes, but differed in the belowground tissues. Field studies show that 7–11%of total legume N was associated with roots and nodules. Data also show an allocation of 11– 14 kg N fixed t−1 belowground dry matter in indeterminate legumes, which represents half the amount of total aboveground plant. This finding demonstrates that investigation relying only on shoot Nunderestimates the role of legumes for soil N fertilityinfo:eu-repo/semantics/publishedVersio