The kinetics-based enzyme-linked immunosorbent assay for coronavirus antibodies in cats: calibration to the indirect immunofluorescence assay and computerized standardization of results through normalization to control values.

The computer-assisted, kinetics-based enzyme-linked immunosorbent assay for coronavirus antibodies in cats was calibrated to the conventional indirect immunofluorescence assay by linear regression analysis and computerized interpolation (generation of "immunofluorescence assay-equivalent" titers). Procedures were developed for normalization and standardization of kinetics-based enzyme-linked immunosorbent assay results through incorporation of five different control sera of predetermined ("expected") titer in daily runs. When used with such sera and with computer assistance, the kinetics-based enzyme-linked immunosorbent assay minimized both within-run and between-run variability while allowing also for efficient data reduction and statistical analysis and reporting of results.     

光照对鸡产蛋性能的影响及其机理研究——Ⅲ.光照对鸡大脑皮质电位的影响

选用22只“星杂579”成龄母鸡,以电生理方法观察了光照(30lx)及在麻醉状态下光照(30lx)和黑暗对其大脑皮质“Wulst”区电位的影响。结果,黑暗时的电位可因光照而抑制;注射氯胺酮麻醉后,电位明显变小,再给黑暗和光照,电位均没有变化。表明大脑皮质参与了光照对鸡的生理调节过程。     

The phenomenon of stress: Concepts and mechanisms associated with stress-induced responses of the neuroendocrine system

Stress, stressors and the stress response are terms which represent concepts rather than oeing precisely definable. No single theory of stress has been universally accepted. Selye's General Adaptation Syndrome of stress remains the primary theory for the basis of stress research in food-producing animals; however, other concepts and theories have been developed. This paper reviews current theories and suggests that the complexity of research on stress in food-producing animals can be attributed to the lack of concrete theories and concepts regarding identifiable stressors, the endocrine responses stimulated by potential stressors and the complex and integrated biological changes in the neuro-endocrine system resulting from exposure to hypothesized stressors.     

The laboratory as an aid to clinical diagnosis

The clinician may use the clinical pathology laboratory as a valuable aid to diagnosis and management, for the assessment of response to treatment, and in preventive medicine programs. Each "link in the chain," that is, sample selection, collection, handling, analysis, result reporting, and interpretation must be carefully and efficiently managed, using an informed combination of art and science, to provide a useful endpoint. This general introduction precedes more specific and detailed articles.     

Fatty acid profiles and sensory and carcass traits of tissues from steers and swine fed an elevated monounsaturated fat diet

Twelve Angus X Hereford steers were assigned to either a control high-energy diet or a test diet consisting of 20% rapeseed at the expense of 20% corn. Twelve pigs were allotted to a control diet and two test diets containing either 10 or 20% canola oil (CO). Both CO and oil in the rapeseed contained 60 to 64% oleic acid. Cattle fed rapeseed exhibited little effect from the diet due to apparent indigestibility of the rapeseed. Total saturated fatty acids decreased from 40% in adipose tissue of the control pigs to 15% in the 20% CO-fed pigs. The ratio of monounsaturated to saturated fatty acids (M/S) increased from 1.19 in adipose tissue from control pigs to 3.63 with the addition of 20% CO to the diet. In muscle, the M/S ratio increased from 1.21 in control pigs to 2.46 in the 20% CO treatment group. The percentage of the saturated fatty acids in muscle decreased from 42% in the control to 23% in the 20% CO treatment. Significant increases in "oiliness" and decreases in fat firmness were observed when increasing levels of canola oil were fed. Sensory traits, cooking loss and shear-force values of pork chops were similar among treatment groups. In conclusion, monounsaturated fatty acid content can be elevated substantially in pork without adversely influencing the quality of the meat, thus producing a product perceived to be more healthful by the consumer.     

Dark lines formed between colonies of isolates of phoma exigua var. foveata on a semi-selective medium

Samenvatting In het Instituut voor Plantenziektenkundig Onderzoek (IPO) te Wageningen wordt gangreen bij aardappel, veroorzaakt door de schimmelPhoma exigua var.foveata, onderscheiden van ander droogrot door aangetast weefsel uit te leggen op een semiselectief medium. Op dit medium wordt de vorming van kristallen van voor de schimmel kenmerkende anthrachinonen bevorderd. De gemakkelijk waar te nemen geelgroene kristallen in het medium wijzen op de aanwezigheid van de betrokken schimmel. Bij een van deze toetsen vormden zich tussen de zich ontwikkelende kolonies van de schimmel donkere lijnen. Deze lijnen verschilden van reeds eerder beschreven violette lijnen, die zich vormen tussen kolonies van de twee variëteitenexigua enfoveata vanP. exigua. Onderzoek aan 27 isolaten vanP. exigua var.foveata toonde aan dat er met betrekking tot de vorming van donkere lijnen 11 verschillende typenP. exigua var.foveata onderscheiden konden worden. Isolaten van deze typen vormden bij gepaarde groei op het selectieve medium donkere lijnen met andere typen, maar niet met isolaten van het zelfde type. Er bleek geen verband met het groeitype van de cultures noch met de vorming van het antibioticum E te bestaan.