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The thyroglobulin of a ram of the East Friesian milk sheep breed suffering from goitre was investigated by physico- and immunochemical methods. The respective ram was the only animal amongst the other sheep of the flock, that exhibited severe goitre, additionally showing depressed behaviour. Results of the thyroid-stimulating hormone response test were indicative of hypothyroidism. The dysfunction of the thyroid gland could be treated by additional iodine supplementation quite successfully, although all sheep had been given iodinated cattle salt throughout the course of the history. Without reducing conditions sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS–PAGE) of isolated thyroglobulin molecules of the ram and control sheep did not reveal different band patterns, but under reducing conditions different band patterns were evident for the respective animals: the ram's thyroglobulin displayed two main bands, those of healthy reference sheep only one. Both bands reacted equally with anti-thyroglobulin antibodies, even with those produced by immunizing rabbits with single bands. The reduced single thyroglobulin band of healthy sheep corresponded to a truncated form of that molecule, whereas the additional main band of the ram was a more resistent, intact thyroglobulin subunit, as was shown by mass spectrometry. In conclusion, results of physico- and immunochemical investigations gave evidence of a modification of thyroglobulin with suspected different iodine binding properties in the ram. The latter finding may have clinical relevance in similar cases in other species, as it is an example of the impact that a minor change in a protein molecule may have on a complete metabolic pathway. Additionally, it could be shown, that in the ovine species the generally found single main band of thyroglobulin after reduction is a truncated form and not an intact subunit. This truncation seems to be induced in vitro by the reductive sample pretreatment prior to SDS-PAGE. [ABSTRACT FROM AUTHOR]

Catecholamine and Cortisol Concentrations in Plasma from Cows at Term: Cows with spontaneous parturition (n = 8) and cows with flumethasone (n = 3) or prostaglandin (n = 3) induced parturition were used in this study. Catecholamine concentrations from cows in the periparturient period were measured in order to evaluate the stress of birth on the dam and the calf. The plasma content of both norepinephrine and epinephrine in late pregnancy was not different from control values in the 3rd to 6th month of pregnancy (norepinephrine 3.27 ± 0.99 nmol/l plasma and epinephrine 0.98 ± 0.45 nmol/l plasma), though both parameters appear elevated in the pregnant group. Norepinephrine concentrations rose to a value of 4.50 nmol/l immediately after birth, whereas epinephrine levels did not show an increase post partum. In two neonates norepinephrine and epinephrine values were 2-3 times higher than in the dams and decreased to the values of the dams within 48 hours. Synthetic glucocorticoids can mimic the increase of Cortisol, which leads to birth. Cortisol concentrations in the cows remained unaffected by induction of parturition by prostaglandins. Newborn calves showed values of about 330 nmol/l, which also declined within 48 hours to values similar to those measured in the dam (9-28 nmol/l). As stress and exogenous glucocorticoids may affect antibody production, the IgG-content of the colostrum was examined. Prostaglandin induction of birth did not alter the IgG-content of colostrum, but flumethasone produced a decrease of about 14.5 %. It is therefore concluded that pre-term birth induction does not produce negative effects on the supply of IgG. Zusammenfassung In dieser Studie wurden Kühe mit physiologischer Geburt (n = 8) sowie Tiere mit Prostaglandin- (n = 3) und Flumethason-induzierter Geburt (n = 3) verwendet. Katecholaminkonzentrationen im Plasma von Kühen um die Geburt wurden gemessen, um anhand dieser Substanzen das Streßgeschehen zu untersuchen, dem Kuh und Kalb während des Geburtsvorganges ausgesetzt sind. Der Plasmagehalt von Noradrenalin und Adrenalin im Endstadium der Trächtigkeit war von Vergleichswerten von Muttertieren im 3. bis 6. Graviditätsmonat nicht signifikant verschieden (Noradrenalin 3,27 ± 0,99 nmol/l und Adrenalin 0,98 ± 0,45 nmol/l Plasma). Die Noradrenlinkonzentrationen des Plasmas stiegen unmittelbar nach der Geburt auf Werte von ca. 4,50 nmol/l an, die Adrenalinwerte blieben unverändert. Bei zwei neugeborenen Kälbern waren die Noradrenalin- und Adrenalinwerte gegenüber den Muttertieren etwa 2-3 fach erhöht. Innerhalb von 48 Stunden nach der Geburt sanken die Hormonkonzentrationen auf die Werte der Muttertiere ab. Synthetische Glukokortikoide können den Cortisolanstieg, der zur Geburt führt, nachahmen. Die Cortisolwerte waren bei Muttertieren mit Prostaglandin-induzierter Geburt, verglichen mit spontan gebärenden Tieren, nicht unterschiedlich. Neugeborene Kälber zeigten Werte um 330 nmol/l. Diese Werte sanken innerhalb von 48 Stunden nach der Geburt gleichfalls in den Bereich der Konzentrationen der Muttertiere (9-28 nmol/l) ab. Da Streß und exogene Glukokortikoide die Antikörperproduktion hemmen können, wurde der IgG-Gehalt des Kolostrums untersucht. Die Prostaglandininduktion hatte keinen Einfluß auf den IgG-Gehalt und auch nach Flumethasonverabreichung war die Antikörperkonzentration des Kolostrums nur um 14,5 % niedriger als in der Kontrollgruppe. Es ist daher anzunehmen, daß sich auch eine frühzeitige Gebunsinduktion nicht nachteilig auf die Immunglobulinversorgung der Kälber auswirkt. [ABSTRACT FROM AUTHOR]

The effect of factors including the horses' farm environment, their sex and age and whether they suffered from summer seasonal recurrent dermatitis (sweet itch) on the concentrations of zinc in the plasma, whole blood and blood cells of 104 Icelandic horses was investigated. Its concentration in plasma varied significantly between farms (P«0.01), but its concentration in blood and blood cells was not influenced by any of the variables. The concentration of zinc in the blood cells was 10.5 times greater than in plasma, but its concentration in plasma was not correlated with its concentration in whole blood or blood cells owing to the variability in the proportion of whole blood zinc present in plasma (relative plasma zinc), which ranged between 9 and 24 per cent This variability was significantly influenced by a three-way interaction between farm, sex and sweet itch (P«0.05). Relative plasma zinc was positively correlated with absolute plasma zinc (r=0.78, P«0.001) and negatively correlated with whole blood and blood cellular zinc (r=-0.58, r=-0.71, P«0.001). [ABSTRACT FROM AUTHOR]

The failure of clearance mechanisms in the mare's uterus results in persistent inflammation and is considered a major cause of subfertility. Eighteen mares, of which three were susceptible to endometritis and four had been ovariectomised, underwent charcoal clearance testing to evaluate their clearance mechanisms. This consisted of installing 500 mg of charcoal (particle size 4 to 90 pm) added to 50 ml of phosphate-buffered saline (PBS) into the uterus. Forty-eight hours later the uterus was flushed out with 0-0012 per cent methylene blue in 50 ml of PBS for determination of the diluting factor by photospectrometry. Flush volume, pH, specific gravity and pellet size were all analysed. To investigate the effect of a β2-adrenergic agonist on the ability of genitally healthy oestrous mares to eliminate a suspension of charcoal from the uterus, four genitally healthy mares with appropriate charcoal clearance were also subjected to clearance testing following intravenous administration of 0-8 µg/kg of clenbuterol every 12 hours and 1 µg/kg of clenbuterol every eight hours. All parameters were within their normal range following clenbuterol treatment However, minimal but significant differences in pre- and post-treatment values regarding fluid volume and extinction rate were recorded. [ABSTRACT FROM AUTHOR]