Anatomic variations and degenerative changes in the collateral cartilages and middle and distal phalanges of the forelimb in Ardenner colts

The anatomic variations and the degenerative changes in the collateral cartilages and middle and distal phalanges in 6 Ardenner colts were characterized by radiography, scintigraphy, and magnetic resonance imaging (MRI). The radiographic changes were assessed between the ages of 16.5 and 25 months. An anatomic variation of the middle and distal phalanges was demonstrated in some of the colts. MRI examination of the 6 colts revealed an association between the deep digital flexor tendon cross-sectional area and body weight as well as foot circumference. Also, a thin collateral sesamoidean (suspensory navicular) ligament was observed subjectively. The presence of an extensive ossification of the collateral cartilages of the foot was found in these young horses. The ossification was characterized by the existence of 2 separate ossification centers, which had a tendency to unite. The radiographic interphalangeal degenerative lesions seen appear as bone remodeling of the dorsal edges of the middle and distal phalanx, on the insertion sites of collateral ligaments of the distal interphalangeal joint, the digital extensor tendon, and the distal interphalangeal joint capsule.     

Essai de détermination de la taille de l'échantillon pour l'étude du potentiel semencier d'un sol

L'étude quantitative du potentiel semencier d'un sol cultivé pose le problème du nombre de prélèvements à réaliser pour avoir une estimation satisfaisante du nombre de semences par hectare. Les prélèvements sont traités séparément et analysés espèce par espèce. On a constaté une relation linéaire entre la moyenne et la variance de la population (après transformation logarithmique), ce qui permet de déterminer la taille de l'échantillon en fonction d'une part, du nombre moyen de semences par prélèvement, d'autre part, du degré de précision souhaité. En pratique, une centaine de prélèvements est nécessaire pour obtenir une précision de 20 à 70 p. 100 (au seuil de 5 p. 100) lorsque le nombre moyen de semences par prélèvement varie de 5 à 0, 1. Study of the size of the sampling for the study of the buried weed seed bank The quantitative study of the weed seed bank of a cultivated soil involves the problem of the number of cores which need to be taken to give a satisfactory estimation of the number of seeds per hectare. The soil cores were treated separately and analysed species by species. There is a linear regression between the mean and the variance of the seed population (after logarithmic transformation) that allows the determination of the number of cores as well as the mean number of seeds per core with the required precision. In practice, one hundred cores was necessary to obtain a precision from 20 to 70% (at 5% level) when the mean number of seeds by core vary from 5 to 0, 1. Studie über die Entnahme von Bodenproben zur Bestimmung des Samenvorrats eines Ackerbodens Eine quantitative Bestimmung des Samenvorrats eines Bodens stellt uns vor das Problem wieviele Bodenmuster zu entnehmen sind, um eine zuverlässige Schätzung der Samenmenge pro Hektar zu erhalten. Die Bodenmuster werden einzeln ausgewartet und auf die vorhandenen Samenarten analysiert. Es wurde eine lineare Beziehung zwischen dem Mittel und der Varianz der Samen-population (nach logarithmischer Transformation) festgestellt, was die Bestimmung des Umfangs der Proben ermöglicht; einerseits in Funktion der mittleren Samenzahl pro Probe, andrerseits in Funktion der gewünschten Genauigkeit. In der Praxis sind ca. 100 Probenentnahmen notwendig um eine Zuverlässigkeit von 20–70% (auf dem Niveau von 5%) zu erreichen, wenn die mittlere Samenzahl pro Muster zwischen 5 und 0,1 liegt.     

Plasma Concentration of Insulin-like Growth Factor I (IGF-I) in Growing Ardenner Horses Suffering from Juvenile Digital Degenerative Osteoarthropathy

Degenerative osteoarthropathy resulting in a reduced active lifespan was observed in Ardenner horses. In the context of joint biology, insulin-like growth factor I (IGF-I) is a potential candidate to affect the anabolism of cartilage matrix molecules. A group of 30 Ardenner horses reared under standardized conditions from weaning were evaluated periodically from 15 to 28 months of age to detect the early manifestations of the disease. At the end of this period, horses were classified in two pathological groups related to the degree of interphalangeal degenerative osteoarthropathy based on clinical and radiographic evaluations: healthy (46.7%) and pathological (53.3%) horses. Seven sequential blood samples were taken from each horse (during the evaluation period) to study the variation of IGF-I plasma concentration. We tested the variations of the IGF-I plasma concentration during growth, and the effect of sex and of pathological classes. Significant variations were observed during the research period, with a maximum value corresponding to spring and a minimum in autumn. A significant reduction of the IGF-I plasma concentration was also observed in the pathological horses (433.5 +/- 19.5 ng/ml) compared to the healthy horses (493.9 +/- 18.2 ng/ml). An alteration in the level of this growth factor could induce a disregulation of the mechanisms involved in the local control of joint and bone tissue development.     

Correlated responses in sow appetite, residual feed intake, body composition, and reproduction after divergent selection for residual feed intake in the growing pig

Residual feed intake (RFI) has been explored as an alternative selection criterion to feed conversion ratio to capture the fraction of feed intake not explained by expected production and maintenance requirements. Selection experiments have found that low RFI in the growing pig is genetically correlated with reduced fatness and feed intake. Selection for feed conversion ratio also reduces sow appetite and fatness, which, together with increased prolificacy, has been seen as a hindrance for sow lifetime performance. The aims of our study were to derive equations for sow RFI during lactation (SRFI) and to evaluate the effect of selection for RFI during growth on sow traits during lactation. Data were obtained on 2 divergent lines selected for 7 generations for low and high RFI during growth in purebred Large Whites. The RFI was measured on candidates for selection (1,065 pigs), and sow performance data were available for 480 sows having from 1 to 3 parities (1,071 parities). Traits measured were sow daily feed intake (SDFI); sow BW and body composition before farrowing and at weaning (28.4 ± 1.7d); number of piglets born total, born alive, and surviving at weaning; and litter weight, average piglet BW, and within-litter SD of piglet BW at birth, 21 d of age (when creep feeding was available), and weaning. Sow RFI was defined as the difference between observed SDFI and SDFI predicted for sow maintenance and production. Daily production requirements were quantified by litter size and daily litter BW gain as well as daily changes in sow body reserves. The SRFI represented 24% of the phenotypic variability of SDFI. Heritability estimates for RFI and SRFI were both 0.14. The genetic correlation between RFI and SRFI was 0.29 ± 0.23. Genetic correlations of RFI with sow traits were low to moderate, consistent with responses to selection; selection for low RFI during growth reduced SDFI and increased number of piglets and litter growth, but also increased mobilization of body reserves. No effect on rebreeding performance was found. Metabolic changes previously observed during growth in response to selection might explain part of the better efficiency of the low-RFI sows, decreasing basal metabolism and favoring rapid allocation of resources to lactation. We propose to consider SRFI as an alternative to SDFI to select for efficient sows with reduced input demands during lactation.     

Gammaglobulin and selenium status in healthy neonatal dairy calves in Switzerland

Serum samples from 142 calves and their dams were analyzed for gammaglobulins (gammaG, calves) and selenium concentrations (Se, calves and dams). A questionnaire provided information about birth and colostrum management. The calves and their dams were distributed into two groups according the calves' gammaG concentration (< 10 and >= 10 g/L), Se concentrations were compared between groups. The correlation between gammaG and Se concentrations in the calves and their dams was analyzed. Risk factors for failure of passive transfer and Se deficiency were assessed based on the questionnaire. The gammaG concentration of 42.9 % of the calves was < 10 g/L (median: 10.9). Calves showed significantly higher gammaG values after optimized colostrum administration than calves with suboptimal colostrum administration (p < 0.004). The median Se concentration was 26.8 and 36.5 μg/L for the calves and dams, respectively. A high correlation was observed between the Se concentration of the dam and her calf (r = 0.72, p < 0.001). The calves' Se and gammaG concentrations were not significantly correlated. These results demonstrate that further efforts toward better information of farmers regarding colostrum management and Se supply are warranted.     

CRACM1 is a plasma membrane protein essential for store-operated Ca2+ entry

Store-operated Ca2+ entry is mediated by Ca2+ release-activated Ca2+ (CRAC) channels following Ca2+ release from intracellular stores. We performed a genome-wide RNA interference (RNAi) screen in Drosophila cells to identify proteins that inhibit store-operated Ca2+ influx. A secondary patch-clamp screen identified CRACM1 and CRACM2 (CRAC modulators 1 and 2) as modulators of Drosophila CRAC currents. We characterized the human ortholog of CRACM1, a plasma membrane-resident protein encoded by gene FLJ14466. Although overexpression of CRACM1 did not affect CRAC currents, RNAi-mediated knockdown disrupted its activation. CRACM1 could be the CRAC channel itself, a subunit of it, or a component of the CRAC signaling machinery.     

Electron acceleration by a wake field forced by an intense ultrashort laser pulse

Plasmas are an attractive medium for the next generation of particle accelerators because they can support electric fields greater than several hundred gigavolts per meter. These accelerating fields are generated by relativistic plasma waves-space-charge oscillations-that can be excited when a high-intensity laser propagates through a plasma. Large currents of background electrons can then be trapped and subsequently accelerated by these relativistic waves. In the forced laser wake field regime, where the laser pulse length is of the order of the plasma wavelength, we show that a gain in maximum electron energy of up to 200 megaelectronvolts can be achieved, along with an improvement in the quality of the ultrashort electron beam.     

Genetic parameters for residual feed intake in growing pigs, with emphasis on genetic relationships with carcass and meat quality traits

Data were collected over the first 4 generations of a divergent selection experiment for residual feed intake of Large White pigs having ad libitum access to feed. This data set was used to obtain estimates of heritability for residual feed intake and genetic correlations (r(a)) between this trait and growth, carcass, and meat quality traits. Individual feed intake of group-housed animals was measured by single-space electronic feeders. Upward and downward selection lines were maintained contemporarily, with 6 boars and 35 to 40 sows per line and generation. Numbers of records were 793 for residual feed intake (RFI1) of boar candidates for selection issued from first-parity (P1) litters and tested over a fixed BW range (35 to 95 kg) and 657 for residual feed intake (RFI2) and growth, carcass, and meat quality traits of castrated males and females issued from second-parity (P2) litters and tested from 28 to 107 kg of BW. Variance and covariance components were estimated using REML methodology applied to a series of multitrait animal models, which always included the criterion for selection as 1 of the traits. Estimates of heritability for RFI1 and RFI2 were 0.14 +/- 0.03 and 0.24 +/- 0.03, respectively, whereas the estimate of r(a) between the 2 traits was 0.91 +/- 0.08. Estimates of r(a) indicated that selection for low residual feed intake has the potential to improve feed conversion ratio and reduce daily feed intake, with minimal correlated effect for ADG of P2 animals. Estimates of r(a) between RFI2 and body composition traits of P2 animals were positive for traits related to the amount of fat depots (r(a) = 0.44 +/- 0.16 for carcass backfat thickness) and negative for carcass lean meat content (r(a) = -0.55 +/- 0.14). There was a tendency for a negative genetic correlation between RFI2 and carcass dressing percent (r(a) = -0.36 +/- 0.21). Moreover, selection for low residual feed intake is expected, through lower ultimate pH and lighter color, to decrease pork quality (r(a) = 0.77 +/- 0.14 between RFI2 and a meat quality index intended to predict the ratio of the weight of ham after curing and cooking to the weight of defatted and boneless fresh ham).