The relationship between carcass characteristics,plasma hormones and metabolites in young fattening bulls

Six Belgian Blue bulls (double-muscled type) and six Friesian bulls were offered a fattening diet for 34 weeks. Plasma samples were obtained once a week and also every 20 min over a 24 h period, 7 weeks before slaughter.No differences were observed between the breeds in plasma glucose, urea and free amino nitrogen concentrations, while creatinine was significantly higher in the Belgian Blue bulls. Tri-iodothyronin, tetra-iodothyronin, insulin-like growth factor 1, insulin and testosterone concentrations were higher in the Holstein group. In contrast, the Belgian Blue bulls appeared to produce more growth hormone. The slaughter weight, carcass weight, dressing percentage and proportion of lean meat were significantly higher in the Belgian Blue group. The characteristics of muscle mass (carcass weight, dressing percentage and proportion of lean meat) were positively correlated with creatinine and with the total peak area or peak amplitude of growth hormone. The insulin concentration was positively correlated with the proportion of adipose tissue in the carcass and negatively correlated with the proportion of muscle. There were no correlations between the carcass characteristics and insulin-like growth factor 1 or testosterone. No further information was provided when the ratios of the hormones were correlated with carcass characteristics.     

Relation of lactose levels in milk and indicators of mammary gland health in the first third of lactation]

A total of 662 bucket milk samples from cows of two breed groups were examined: red and white breed = Bohemian Pied cattle with different genetic proportions of Ayrshire and Red Holstein improvement breeds; black and white breed = Black and White Lowland breed and different degree of absorptive crossing with a genetic proportion of the Holstein breed. Samples of daily milk yields were taken in the first three months of lactation once a month within a year. A possibility of using lactose content as an auxiliary indicator for detection of the mammary gland secretion disorders in the initial lactation stage was evaluated. The average values of the different indicators and their variability are summarized in Tab. I showing also the significance in a statistical model of included effects. Lactose content (L) was 4.88 +/- 0.20%, chloride content (Cl-) 113.7 +/- 22.4 mg/100 ml, somatic cell (SC) count 474 +/- 805 thousand/ml, SC count log corresponds to the geometrical mean of 234 thousand/ml, titratable acidity (SH) 7.34 +/- 0.83 x 2.5 mmol/l, chloride-lactose ratio (ClL) 2.27 +/- 0.51, conductivity (gamma) 442.4 +/- 34.5 mS/m and mastitis test (MT-NK) 0.72 +/- 1.18. The efficiency of the used statistical model was highest for Cl- content (Tab. I, R2 = 0.41), and it was lowest for SC counts (R2 = 0.07), while it increased to the twofold value (R2 = 0.15) after logarithmic transformation of SC counts. The breed group exerted a significant effect on Cl-, SC, log SC, SH, ClL, gamma and MT-NK (Tab. I). The breed group of red and white cows (Tab. II) had higher component contents and better indicators of the udder health state (Cl-, SC, log SC, ClL, gamma and MT-NK). The month of lactation influenced significantly SC, log SC, SH and gamma (Tab. I). A decrease in SC counts with the accruing month of lactation was observed (Tab. II), the trend of gamma and SH was opposite. The effect of lactation number was found to be significant for L, SC, log SC, SH, ClL, gamma and MT-NK (Tab. I). A tendency of a gradual decrease with the lactation number was observed in these indicators: L, SH, proteins and solids-non-fat (Fig. 1), while Cl-, gamma and ClL showed an opposite tendency. The year season influenced significantly L, log SC, SH, ClL, gamma and MT-NK (Tab. I, Fig. 2).(ABSTRACT TRUNCATED AT 400 WORDS)     

Influence of Adrenalectomy on the Developing Rat Thymus During Peri-Weaning Period

Adrenalectomy of 17-, 18- and 19-day-old male and female rats did not cause any changes in the weight of thymus 4 days later. Adrenalectomy on day 20 of age induced a significant hypertrophy of the thymus 4 days later. These results indicate that on day 20 of age, just before weaning, the thymus is under some inhibitory regulation by the adrenal gland.     

Porcine epidemic abortion and respiratory syndrome (mystery swine disease). Isolation in Spain of the causative agent and experimental reproduction of the disease.

In March of 1991, a disease that affected pregnant sows and caused a high mortality in unweaned piglets was detected in Spain. Based on the clinical signs observed, mystery swine disease, which had been described recently in Germany, Holland and Belgium, was suspected. From the samples obtained from the affected farm, a filtrable agent (0.22 micron) was isolated on cell culture. It produced cytopathic effects, its replication was intracytoplasmic, it was sensitive to chloroform, and cross-reacted with a Lelystad reference serum. When inoculated into pregnant sows, the agent produced inappetence for 2-4 days, without hyperthermia. One of the sows aborted at 100 days of gestation; the two others had delayed parturitions (days 115 and 116). There was a mixture of healthy piglets, mummified fetuses, stillbirths and weak piglets. Microscopic examination of the lungs of healthy piglets killed at 8 and 12 days of life revealed the presence of interstitial pneumonia. The sera from the three sows at 39 days after infection cross-reacted with the Lelystad virus (titres > or = 1/640), whereas pre-inoculation sera did not recognize it (titres < or = 1/10). This is the first report from Spain of the isolation of an agent (antigenically related to the Lelystad virus), capable of reproducing the disease previously designated as mystery swine disease.     

Proteome analysis of the sarcoplasmic fraction of pig semimembranosus muscle: implications on meat color development

Two-dimensional electrophoresis was used to investigate sarcoplasmic protein expression in pig Semimembranosus muscles sampled 20 min after slaughter. Two groups (light and dark) of 12 animals were selected from 1000 pigs, based on meat L values measured 36 h postmortem. Twenty-two proteins or fragments (p < 0.05) were differentially expressed. Muscles leading to darker meat had a more oxidative metabolism, indicated by more abundant mitochondrial enzymes of the respiratory chain, hemoglobin, and chaperone or regulator proteins (HSP27, alphaB-crystallin, and glucose-regulated protein 58 kDa). Conversely, enzymes of glycolysis were overexpressed in the lighter group. Such samples were also characterized by higher levels of glutathione S-transferase omega, which can activate the RyR calcium channels, and higher levels of cyclophilin D. This protein pattern is likely to have severe implications on postmortem metabolism, namely, acceleration of ATP depletion and pH fall and subsequent enhanced protein denaturation, well-known to induce discoloration.     

Laryngeal paralysis-polyneuropathy complex in young related Pyrenean mountain dogs

OBJECTIVES: To characterise clinical, electrophysiological and histopathological findings. To analyse pedigree information in six young related Pyrenean mountain dogs with laryngeal paralysis-polyneuropathy complex (LP-PNC). METHODS: A retrospective study of clinical records and pedigrees of six young related Pyrenean mountain dogs with LP-PNC was carried out. RESULTS: All dogs were presented with laryngeal paralysis and concurrent megaoesophagus. Electrodiagnostic testing was performed in three dogs and showed electrophysiological abnormalities in the distal appendicular muscles. Histopathological findings of peripheral nerve samples were dominated by distal axonal degeneration. Clinical, electrophysiological and histopathological findings were supportive of a diagnosis of degenerative, sensorimotor LP-PNC, similar to that reported in young dalmatians and rottweilers. All dogs died or were euthanased by two years of age. An autosomal recessive mode of inheritance was suspected based on pedigree analysis. CLINICAL SIGNIFICANCE: Congenital LP-PNC should be suspected in any young dog presenting with laryngeal dysfunction and other concurrent neurological abnormalities. The prognosis is usually poor.     

Chocolate is a powerful ex vivo and in vivo antioxidant, an antiatherosclerotic agent in an animal model, and a significant contributor to antioxidants in the European and American Diets

Chocolate today is often viewed as a food or snack with little nutritional value. The high saturated fat content of chocolate has also contributed to the belief that its consumption increases the risk of heart disease. However, recent human studies have proven that chocolate has beneficial effects on some pathogenic mechanisms of heart disease such as endothelial function and blood pressure. Although the antioxidant properties of chocolate have been known for some time, there has been no examination of its place in the U.S. diet as a source of antioxidants. This paper demonstrates that chocolate makes a significant contribution to U.S. per capita dietary antioxidants and by inference the European Community's. In the U.S. diet chocolate is the third highest daily per capita antioxidant source. An ex vivo study shows that epicatechin, a major polyphenol in chocolate and chocolate extracts, is a powerful inhibitor of plasma lipid oxidation due to polyphenols' ability to bind to lower density lipoproteins. Conversely, the fat from chocolate alone is a pro-oxidant in this model. This is also demonstrated in an in vivo human study. After consumption of dark chocolate and cocoa powder, the lower density lipoproteins isolated from plasma were protected from oxidation compared to the lipoproteins isolated after cocoa butter consumption, which were put under oxidative stress. In an animal model of atherosclerosis, cocoa powder at a human dose equivalent of two dark chocolate bars per day significantly inhibited atherosclerosis, lowered cholesterol, low-density lipoprotein, and triglycerides, raised high-density lipoprotein, and protected the lower density lipoproteins from oxidation. Chocolate has thus been shown to have potential beneficial effects with respect to heart disease.     

Dipolar antiferromagnetism and quantum criticality in LiErF₄

Magnetism has been predicted to occur in systems in which dipolar interactions dominate exchange. We present neutron scattering, specific heat, and magnetic susceptibility data for LiErF(4), establishing it as a model dipolar-coupled antiferromagnet with planar spin-anisotropy and a quantum phase transition in applied field H(c|| = 4.0 ± 0.1 kilo-oersteds. We discovered non-mean-field critical scaling for the classical phase transition at the antiferromagnetic transition temperature that is consistent with the two-dimensional XY/h(4) universality class; in accord with this, the quantum phase transition at H(c) exhibits three-dimensional classical behavior. The effective dimensional reduction may be a consequence of the intrinsic frustrated nature of the dipolar interaction, which strengthens the role of fluctuations.     

Unraveling the life history of successful invaders

Despite considerable current interest in biological invasions, the common life-history characteristics of successful invaders remain elusive. The widely held hypothesis that successful invaders have high reproductive rates has received little empirical support; however, alternative possibilities are seldom considered. Combining a global comparative analysis of avian introductions (>2700 events) with demographic models and phylogenetic comparative methods, we show that although rapid population growth may be advantageous during invasions under certain circumstances, more generally successful invaders are characterized by life-history strategies in which they give priority to future rather than current reproduction. High future breeding expectations reduce the costs of reproductive failure under uncertain conditions and increase opportunities to explore the environment and respond to novel ecological pressures.     

Regulated virulence controls the ability of a pathogen to compete with the gut microbiota

The virulence mechanisms that allow pathogens to colonize the intestine remain unclear. Here, we show that germ-free animals are unable to eradicate Citrobacter rodentium, a model for human infections with attaching and effacing bacteria. Early in infection, virulence genes were expressed and required for pathogen growth in conventionally raised mice but not germ-free mice. Virulence gene expression was down-regulated during the late phase of infection, which led to relocation of the pathogen to the intestinal lumen where it was outcompeted by commensals. The ability of commensals to outcompete C. rodentium was determined, at least in part, by the capacity of the pathogen and commensals to grow on structurally similar carbohydrates. Thus, pathogen colonization is controlled by bacterial virulence and through competition with metabolically related commensals.