Determination of sulfamethazine and trimethoprim in liquid feed premixes by HPLC and diode array detection, with an analysis of the uncertainty of the analytical results.

Sulfamethazine (SMZ) and trimethoprim (TMP) are antibacterials used in veterinary practice. This paper describes a method for their determination in veterinary liquid feed premixes that is based on liquid chromatography with diode array detection. Gradient elution with methanol and ammonium acetate achieved excellent separation of the two analytes within 15 min without any interference from the matrix. Absorbance of the column effluent was monitored at 264 nm for SMZ and at 230 nm for TMP. Detailed analyses of the uncertainties of determinations afford estimated expanded uncertainties of, respectively, 0.2 and 0.1 w/v % for typical SMZ and TMP concentrations of 10.7 and 2.1 w/v %, respectively. At the lower end of the calibrated range of the method, the dominant source of uncertainty is the preparation of standards and the construction of the calibration line.     

The anti-proteolytic activity of blood and ovarian follicular fluid in sheep after stimulation with serum gonadotropin (PMSG) and administration of Antisergon]

The synthesis and secretion of trypsin (trypsin model serine protease) inhibitors are regulated in ovarian follicles by gonadotropins. The superovulation stimulations with 400 IU FSH, 1000 IU PMSG, 1000 IU HCG, 750 IIU PMSG + 750 IU HCG influence in a different way the trypsin inhibiting activities (TIA) of blood plasma (BP) (Figs 1 and 2) and follicular fluid (fig. 3); this points to a possibility of local effects. An increase in the average values of TIA in BP was statistically significant during the whole experiment: P less than 0.05 to P less than 0.001 (following the administration of PMSG+HCG, or PMSG, and HCG); Antisergon administered in 68 hours after PMSG reduced this increase. The changes in the fraction of low-molecular TIA in BP (after BP treatment with perchloric acid) were of converse nature; a decrease in the average values ranged from P less than 0.02 to P less than 0.001 (following PMSG or other stimulations). Antisergon did not influence this decrease. The changes observed on particular days of the trial (Figs. 1 and 2) also indicate different effects of the preparations, mainly of the component LH, which resulted in the occurrence of large nonovulating follicles (greater than 10 mm--"cystic" ones). No such follicles were observed in nonstimulated ewes and after FSH stimulation. The administration of antisergon (goat's antiserum against PMSG) 68 hours after PMSG administration did not prevent their creation. The TIA of follicular fluid (FF) of antral follicles was on average tenfold in comparison with that of blood plasma; and the TIA FF of follicles greater than 10 mm was higher (up to P less than 0.001) than the TIA FF of follicles less than 10 mm. The administration of Antisergon in shorter intervals following PMSG administration (12, 24, 48 and 58 hours) influenced the average values of TIA BP in 120 hours (since PMSG administration) in dependence on time (Tab. I). The effects of Antisergon administered in 12 and 24 hours after PMSG administration on the TIA BP were insignificant if it was administered in 48 and 58 hours the TIA BP increased (P less than 0.02; P less than 0.001) in comparison with the interval of 12 hours. The TIA FF of follicles less than 5 mm, 5-10 mm and greater than 10 mm varied in dependence on the time intervals of Antisergon administration (Fig. 4). The statistical significance of these changes in shown in Tab. II.(ABSTRACT TRUNCATED AT 400 WORDS)     

Fine needle aspiration biopsy of malignant tumors in dogs and cats: a report of 102 cases

Fine needle aspiration biopsy is a fast and inexpensive technique well tolerated by animals. Its efficacy for the diagnosis of malignancy and determination of cellular origin was investigated for 97 malignant tumors and five benign lesions in 83 dogs and 19 cats. Histological examination of the lesions was performed in each case. Malignancy was detected by cytology in 69% of the malignant tumors. The cellular origin of the lesion was determined in 74% of the cases. Confirmation of malignancy and determination of cellular origin permitted an early diagnosis and prognosis. Since fine needle aspiration biopsy and cytology cannot definitely rule out malignancy, a surgical biopsy and histopathology should be done when malignancy is suspected clinically and not confirmed cytologically. Specimens of good quality, adequate collaboration between the cytologist and clinicians, and sufficient knowledge of pathology and cytology are basic requirements for obtaining good results with fine needle aspiration biopsy and cytology.     

Transitional Cell Carcinoma of the Urinary Bladder in a Beluga Whale (Delphinapterus leucas)

A transitional cell carcinoma of the urinary bladder was found in a beluga whale stranded in the St. Lawrence middle estuary. Various organs of this animal were submitted to high resolution gas chromatography coupled with mass spectrometry analysis. High frequency of urinary bladder cancer in the human population of the same area and the presence of carcinogenic compounds in the marine environment of this animal are discussed.

Concurrent isolation of Edwardsiella tarda from various organs of this whale is also reported.

     

Correct equations for comparing models in diallel analysis

SUMMARY: Correct equations are given to express the parameter estimates of four models for complete diallels as a function of the parameter estimates in the model of Eisen et al. (1983). In recent literature these equations have been partly incorrect. ZUSAMMENFASSUNG: Korrekte Gleichungen für den Vergleich von Modellen in der Diallelanalyse Für die Darstellung der Parametersch?tzwerte von vier Modellen für vollst?ndige Diallele als Funktion der Parametersch?tzwerte des Modells von Eisen et al. (1983), die in der Literatur teilweise fehlerhaft erfolgte, werden korrekte Formeln angegeben.     

Evaluation of an in-office allergy screening test in nonatopic dogs having various intestinal parasites

An in-office allergy screening kit was evaluated in 10 dogs that had no clinical signs of atopy but had various intestinal parasites. All 10 dogs had a positive reaction to the dust mite Dermatophagoïdes farinae, and four dogs had positive reactions to at least one other group of allergens. The kit as presently marketed gives numerous false positive results in parasitized nonatopic dogs.