Ocean ecology: don't fence me in

New research that combines ocean circulation and genetic models to predict population structure of corals will help conservation efforts in tropical reef ecosystems.     

Don't worry,sleep well: predictors of sleep loss over worry

Sleep and Biological Rhythms - In this study, our aim was to explore the relationship between sleep quality/quantity, chronotype, pre-sleep arousal, arousability, stress, coping, neuroticism,...     

Increasing daily feeding occasions in restricted feeding strategies does not improve performance or well being of fattening pigs

Background  

The natural feeding behaviour of the pig is searching for feed by rooting activities throughout the day; self-feeding pigs randomly space their eating and drinking periods throughout the day consuming ten to twelve meals per day. Pigs in conventional fattening pig production are normally fed 2–3 times daily with the feed consumed within 15 minutes. The aim of this study was to determine if more frequent feedings could improve the performance of conventionally kept fattening pigs.     

Life-long well being: applying animal welfare science to nonhuman primates in sanctuaries

Nonhuman primates have become common in sanctuaries, and a few such facilities even specialize in their care. Sanctuaries can improve the well being of many unwanted primates, especially in terms of housing and socialization. However, diverse facilities call themselves sanctuaries, and they have varying conditions, care programs, and restrictions. In addition, a general lack of regulation of sanctuaries for nonhuman animals creates problems in enforcing even minimal standards. The application of animal welfare science in the sanctuary setting can help foster high standards and empirically based decision making. Sanctuaries offer excellent environments for studying primates without the limitations inherent in breeding, exhibition, and medical research facilities. However, some sanctuaries avoid scientific study. Many sanctuaries have little opportunity to study animal welfare in a systematic manner due to financial considerations or a lack of specific expertise among staff and volunteers. Most published sanctuary research involves reintroduction procedures at sanctuaries in source countries. Nevertheless, one chimpanzee sanctuary's successes in performing long-term studies and using simple evaluation methods, such as check sheets, have demonstrated the benefits of applying animal welfare science to sanctuary-housed nonhuman primates.     

Seasonal aerobic performance variations in elite soccer players

The purpose of this study was to examine the seasonal changes in body composition and aerobic performance in elite soccer players. Twelve elite professional soccer players (aged 25 6 5 years, weight 75.7 6 5.3 kg, height 1.79 6 0.06 m) were measured for body fat (%), maximum oxygen consumption (VO2max), running velocity at VO2max (VO2max), running velocity at a fixed blood lactate concentration of 4 mmol · L21 (v-4 mM) at the start of the preseason period, at the beginning of the competitive period, and at midseason. VO2max, v-4 mM, and vVO2max increased significantly (p , 0.05) by 4.5, 10.5, and 7.8,respectively, after the preseason period. Thereafter, the aerobic performance parameters remained relatively constant, with no significant changes throughout the competitive period. The results of this study suggest that moderate improvements were observed in VO2max, and the %VO2max at 4 v-4 mM, whereas higher improvements were observed in VO2max and v-4 mmol · L21 after the preseason training period. On the other hand, during the competitive period, aerobic performance remained unchanged.In addition, this study suggests that heart rate, lactate, vVO2, and VO2max are useful and practical predictors that help monitor aerobic performance changes during a soccer season.     

Biochemical polymorphism in relation to performance in horses

Summary Investigations on relationships between biochemical polymorphism and variation in quantitative traits are of interest from the perspectives of both theoretical quantitative genetics and practical animal breeding. This subject was studied by using racing performance records of more than 25,000 horses of the Swedish Trotter breed born in the period 1970–1979. For all horses data on six blood group and nine electrophoretic loci were available. Two different performance traits were investigated. A racing performance index value was calculated for all individuals which had started in at least five races. Horses which had not started at all or less than five times were pooled in an unstarted class and the proportion of started horses was analysed as an all-or-none trait. The relationships between the marker genes and these two performance traits were analysed statistically by using linear models. Analysis within sires revealed a very highly significant association between variation at the serum esterase locus (Es) and the proportion of started horses. In addition, four weakly significant associations were found. A striking feature of the highly significant association involving the esterase locus was that the effect of different alleles showed a good fit to an additive genetic model as the value of each heterozygous type was intermediate to the two corresponding homozygotes. In addition to the association tests, the possibility of genetic linkage between marker genes and genes affecting performance was tested as well as the influence on performance of heterozygosity at marker loci. No significant relationships were revealed in these latter tests.     

Aerobic fitness and performance in elite female futsal players

Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm) performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET), until volitional fatigue. Outcome variables were exercise heart rate (HR), VO₂, post-exercise blood lactate concentrations ([La]b) and running speeds (km · h^-1). During the treadmill test, VO₂max, maximal aerobic speed (MAS), HR and peak [La]b were 45.3±5.6 ml · kg^-1 · min^-1, 12.5±1.77 km · h^-1, 197±8 beats · min^-1 and 11.3±1.4 mmol · l^-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km · h^-1, 199±8 beats · min^-1 and 12.5±2.2 mmol · l^-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p < 0.0001) with VO₂max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players.     

Locomotor performance of hatchling fence lizards (Sceloporus occidentalis): Quantitative genetics and morphometric correlates

Summary We examined heritabilities and correlations among measures of locomotor performance (speed, stamina) and among possible morphometric determinants of performance (hindlimb span, tail length) in families of hatchling lizards (Sceloporus occidentalis). We were particularly interested in determining whether these traits were heritable and thus might potentially respond genetically to selection. Moreover, we wished to determine whether speed and stamina are negatively genetically correlated, as suggested bya priori physiological and empirical considerations. All four traits appeared to be significantly heritable. Broadsense heritabilities were 0.33–0.36 for speed, 0.35–0.36 for stamina, 0.45–0.51 for hindlimb span, and 0.46–0.47 for tail length. Contrary to expectations, speed and stamina were not negatively genetically correlated. Hindlimb span and tail length, however, were negatively genetically correlated (but not phenotypically correlated). Hindlimb span and stamina were positively phenotypically correlated. Thus, for example, selection for longer hindlimb span could potentially result in shorter tails, contrary to evolutionary predictions based only on phenotypic correlations.     

Endurance training and sprint performance in elite junior cross-country skiers

The purpose of the present study was to investigate the relationship between aerobic characteristics and sprint skiing performance, and the effects of high-intensity endurance training on sprint skiing performance and aerobic characteristics. Ten male and 5 female elite junior cross-country skiers performed an 8-week intervention training period. The intervention group (IG, n = 7) increased the volume of high-intensity endurance training performed in level terrain, whereas the control group (CG, n = 8) continued their baseline training. Before and after the intervention period, the skiers were tested for 1.5-km time-trial performance on roller skis outdoors in the skating technique. Maximal oxygen uptake (VO?max) and oxygen uptake at the ventilatory threshold (VO?VT) were measured during treadmill running. VO?max and VO?VT were closely related to sprint performance (r = ~0.75, both p < 0.008). The IG improved sprint performance, VO?max, and VO?VT from pre to posttesting and improved sprint performance and VO?VT when compared to the CG (all p < 0.01). This study shows a close relationship between aerobic power and sprint performance in cross-country skiing and highlights the positive effects of high-intensity endurance training in level terrain.     

Skeletal muscle properties and performance in elite female track athletes

Selected biochemical and physiological properties of skeletal muscle were studied in light of performance capabilities in 24 elite female track athletes. The feasibility of quantifying end point histochemistry and relating oxidative staining density (reduced nicotinomide adenine dinucleotide diaphorase: NADH-D) to whole body maximal oxygen consumption (VO2 max) was also investigated, while muscle fiber types, classified according to alkaline APTase stains, were studied and related to muscle oxidative capacity (succinate dehydrogenase: SDH), VO2 max and "in vivo" torque-velocity properties. Muscle biopsies were taken from the vastus lateralis of each subject and maximal knee extensor torques were recorded at 30 degrees from full extension at four selected velocities. While results confirm earlier reports on skeletal muscle properties and performance it was concluded that end point histochemistry could be reliably quantified and that an "oxidative" stain such as NADH-D correlates extremely well with VO2 max (r = 0.86, p less than 0.001) whereas correlations between % slow twitch fibres (Alkaline ATPase stain) and VO2 max were lower (r = 0.44, p less than 0.05). Additionally, as knee extension velocity increased from 0-1.7 rad x s-1 angle specific extensor torque production did not decline as observed in vitro and pentathletes displayed significantly larger torques at all velocities when compared to the other athletes. These data confirm that while myofibrillar ATPase staining correlates with force-velocity properties of muscle, VO2 max is better correlated with quantified oxidative staining.     

Biomotor structures in elite female handball players according to performance

In order to identify biomotor structures in elite female handball players, factor structures of morphological characteristics and basic motor abilities, and of variables evaluating situation motor abilities of elite female handball players (n = 53) were determined first, followed by determination of differences and relations of the morphological, motor and specific motor space according to handball performance. Factor analysis of 16 morphological measures produced three morphological factors, i.e. factor of absolute voluminosity, i.e. mesoendomorphy, factor of longitudinal skeleton dimensionality, and factor of transverse hand dimensionality. Factor analysis of 15 motor variables yielded five basic motor dimensions, i.e. factor of agility, factor of throwing explosive strength, factor of running explosive strength (sprint), factor of jumping explosive strength and factor of movement frequency rate. Factor analysis of 5 situation motor variables produced two dimensions: factor of specific agility with explosiveness and factor of specific precision with ball manipulation. Analysis of variance yielded greatest differences relative to handball performance in the factor of specific agility and throwing strength, and the factor of basic motoricity that integrates the ability of coordination (agility) with upper extremity throwing explosiveness and lower extremity sprint (30-m sprint) and jumping (standing triple jump). Considering morphological factors, the factor of voluminosity, i.e. mesoendomorphy, which is defined by muscle mass rather than adipose tissue, was found to contribute significantly to the players'performance. Results of regression analysis indicated the handball performance to be predominantly determined by the general specific motor factor based on specific agility and explosiveness, and by the morphological factor based on body mass and volume, i.e. muscle mass. Concerning basic motor abilities, the factor of movement frequency rate, which is associated with the ability of ball manipulation, was observed to predict significantly the handball players' performance.     

The use of a mirror reduces isolation stress in horses being transported by trailer

Horse trailers are a common form of transportation for horses and ponies and often require the animal to travel alone or with a single companion. The current study investigated the effect of transporting horses alone, in company or with an acrylic safety mirror (measuring 81 cm × 61.5 cm) that provided surrogate companionship. The behavioural and physiological responses of 12 mature horses during a 30-min journey by trailer under the three treatments were compared. Behaviours (vocalisation, eating, head-tossing, pawing, and head-turning) were recorded. In order to assess circulatory changes that occur as part of the response to transport, heart rate (HR), rectal (T_r) and ear-pinna (T_p) temperatures were recorded. When travelling with a live companion significantly less time was spent vocalising (p < 0.001), head-turning (p < 0.001), head-tossing (p < 0.01) and pawing (p < 0.01); eating behaviour increased (p < 0.05). Physiological responses (increases in HR and T_r and decreases in T_p) were also significantly reduced when travelling with a live companion (p < 0.01). Travelling with the mirror did not significantly affect physiological responses compared with travelling alone, but the rise in T_r and fall in T_p was reduced (p = 0.052 and p = 0.051, respectively) and can be considered a trend. When travelling with a mirror significantly less time was spent turning the head (p < 0.01), vocalising (p < 0.05) and head-tossing (p < 0.05); eating behaviour increased (p < 0.05). The only significant difference between travelling with a live companion and a mirror was that the time spent turning the head round was less with a live companion (p < 0.05). The provision of surrogate companionship in the form of a mirror was found to be preferable to travel alone, but where possible a live companion is recommended. Isolation during transportation was found to suppress feeding behaviour. Although peripheral blood flow (T_p) has been used to assess transport stress in other species it has not previously been used in the horse. Further evaluation of this non-invasive measure is now required.     

Seasonal changes in performance and free testosterone: cortisol ratio of elite female rowers

The aim of this study was to investigate the seasonal behaviour of the plasma free testosterone: cortisol ratio (FTCR) and to relate hormonal changes to daily training volume and performance parameters on a rowing ergometer in elite female rowers. During 9 months of training preceding the 1988 Olympic Games the resting values of the FTCR in six elite female rowers were regularly (ten times) studied. Daily training volume was analysed in terms of rowed distance (l_rowad) and time (t). In addition, two performance parameters, the power at 4.0 mmol·l^–1 lactate concentration in the blood and the maximal power, were determined by a test on a rowing ergometer. The results indicated that the mean FTCR test value did not differ significantly from the level of the initial test or from the mean value of the directly preceding test. A significant negative correlation (r=–0.98, P<0.01) between FTCR and l_rowed was found in a period i.e. at a training camp, when there was a sudden increase in training volume. When FTCR was related to t a significant positive correlation (r=0.88, P<0.05) was found only for the period at the training camp. Our data further suggested that the FTCR alone was not an adequate indicator for the anabolic/catabolic balance in elite female rowers. This finding was contrary to previous findings in elite male rowers. However, in training practice the FTCR seems useful as an indicator of the hormonal training status of elite female rowers when complemented with data about total and free testosterone, performance parameters and knowledge concerning cyclic variations of the FTCR.Both departments co-operate in the working group Janus Jongbloed Research Centre, Utrecht, The Netherlands     

Always being well prepared for defense: The production of deterrents by juvenile Chrysomelina beetles (Chrysomelidae)

In response to herbivores, plants produce a variety of natural compounds. Many beetle species have developed ingenious strategies to cope with these substances, including colonizing habitats not attractive for other organisms. Leaf beetle larvae of the subtribe Chrysomelina, for example, sequester plant-derived compounds and use them for their own defense against predators. Using systematically modified structural mimics of plant-derived glucosides, we demonstrated that all tested Chrysomelina larvae channel compounds from the gut lumen into the defensive glands, where they serve as intermediates in the synthesis of deterrents. Detailed studies of the sequestration process revealed a functional network of transport processes guiding phytochemicals through the larval body. The initial uptake by the larvae’s intestine seems to be fairly unspecific, which contrasts sharply with the specific import of precursors into the defensive glands. The Malpighian tubules and hind-gut organs facilitate the rapid clearing of body fluid from excess or unusable compounds. The network exists in both sequestering species and species producing deterrents de novo. Transport proteins are also required for de novo synthesis to channel intermediates from the fat body to the defensive glands for further conversion. Thus, all the tools needed to exploit host plants’ chemistry by more derived Chrysomelina species are already developed by iridoid–de novo producers. Early intermediates from the iridoid–de novo synthesis which also can be sequestered are able to regulate the enzyme activity in the iridoid metabolism.     

Acute effects of verbal feedback on upper-body performance in elite athletes

Argus, CK, Gill, ND, Keogh, JWL, and Hopkins, WG. Acute effects of verbal feedback on upper-body performance in elite athletes. J Strength Cond Res 25(12): 3282-3287, 2011-Improved training quality has the potential to enhance training adaptations. Previous research suggests that receiving feedback improves single-effort maximal strength and power tasks, but whether quality of a training session with repeated efforts can be improved remains unclear. The purpose of this investigation was to determine the effects of verbal feedback on upper-body performance in a resistance training session consisting of multiple sets and repetitions in well-trained athletes. Nine elite rugby union athletes were assessed using the bench throw exercise on 4 separate occasions each separated by 7 days. Each athlete completed 2 sessions consisting of 3 sets of 4 repetitions of the bench throw with feedback provided after each repetition and 2 identical sessions where no feedback was provided after each repetition. When feedback was received, there was a small increase of 1.8% (90% confidence limits, ±2.7%) and 1.3% (±0.7%) in mean peak power and velocity when averaged over the 3 sets. When individual sets were compared, there was a tendency toward the improvements in mean peak power being greater in the second and third sets. These results indicate that providing verbal feedback produced acute improvements in upper-body power output of well-trained athletes. The benefits of feedback may be greatest in the latter sets of training and could improve training quality and result in greater long-term adaptation.     

Match running performance and exercise intensity in elite female Rugby Sevens

The purpose of this study was to describe the match-play demands of professional female rugby players competing in Rugby Sevens (Rugby 7's) matches. Time-motion analyses (global position system) were performed on 12 elite female rugby players during 5 competitive matches in a 2-day international tournament. Data revealed that players covered an average distance of 1,556.2 ± 189.3 m per game (14 minutes). Over this distance, 29.7% (462.6 ± 94.6 m) was spent standing and walking, 33.2% (515.9 ± 88.6 m) jogging, 11.6% (181.0 ± 61.4 m) cruising, 16.4% (255.7 ± 88.3 m) striding, 3.7% (57.1 ± 40.8 m) high-intensity running, and 5.4% (84.0 ± 64.8 m) sprinting. The average maximal distance of sprints, number of sprints, minimum distance of sprint, and mean sprint distance over the game were as follows: 25.8 ± 16.1 m, 5.3 ± 3.2 sprints, 6.5 ± 2.0 m, and 17.2 ± 8.8 m, respectively. The players' work-to-rest ratio was 1:0.4. For over 75% of the game, the players were exposed to heart rates (HRs) >80% of their maximal HR. There were no statistical differences between the first and second halves in any of the variables analyzed. This study suggests that the physical demands of Rugby 7's are quite different from those reported in other rugby codes. For players and teams to remain competitive in female Rugby Sevens, coaching, conditioning, and physical fitness testing should reflect these current demands.