Nintey nonanesthetized 7- to 16-week-old pigs were studied, using 2-dimensional echocardiography that permits orientation of a targeted M-mode beam perpendicular to structures being studied and allows serial studies of the same cardiac regions. Normative data were obtained and included body weight and measurements of left atrial diameter, mitral valve excursion, aortic root diameter, left ventricular end-diastolic and end-systolic diameters, and left ventricular fractional shortening. A positive correlation was found between body weight and measurements of left atrial diameter, mitral valve excursion, aortic root diameter, left ventricular end-diastolic and end-systolic diameters, and fractional shortening. A correlation was found between body weight and age. Best-fit analysis resulted in all measurements fitting either a first- or second-degree polynomial.

Measurement of liver size was made on nuclear scintigraphic images obtained from 16 clinically normal, anesthetized dogs in ventral, dorsal, right and left lateral, and left dorsal oblique positions after administration of technetium 99m-sulfur colloid. Linear measurements of liver length and width were make from each scintiscan, and liver surface area was determined by setting a region of interest manually and by use of a computer count of pixels above a minimal intensity (threshold method). All linear measurements had a statistically significant (P less than 0.05) correlation with liver and body weight, with the exception of the measurements of liver width made on dogs in dorsal and left lateral dorsal oblique positions. The highest correlation (r = 0.89) between the scintigraphic measurements and liver weight was the multiplication of measurements of liver width and length from the right lateral view. Although all area determinations were significantly (P less than 0.05) correlated with liver and body weight, for most views, the manual method of determining the region of interest had a slightly better correlation with the liver weight than did the threshold method.

The relationship of serum complement activity and bacteriostatic activity was investigated in male guinea pigs given aflatoxin and/or rubratoxin. In experiment 1, guinea pigs were given 0.6 mg of aflatoxin/kg of body weight, PO, once. In experiment 2, guinea pigs were given 0.02 mg of aflatoxin/kg, PO, and/or 8 mg of rubratoxin, PO, 11 times. Aflatoxin (0.02 mg/kg) had no effect given alone, but potentiated the effect of rubratoxin. In both experiments, changes in complement activity were accompanied by similar but not always significant (P less than 0.05) changes in bacteriostatic activity of serum. Guinea pigs given 0.06 mg of aflatoxin/kg had significant (P less than 0.05) changes in complement titers and in serum alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase activities. Guinea pigs given repeated oral doses of aflatoxin and/or rubratoxin had changes in complement titers, bacteriostasis, and alkaline phosphatase and aspartate aminotransferase activities, but not in alanine aminotransferase activities. Significant differences were detected only when average values for all guinea pigs given rubratoxin or rubratoxin with aflatoxin were compared with average values for guinea pigs not given rubratoxin.

The effect of fungi on the growth of body organs in mice was investigated. Single, intraperitoneal injections of yeasts (Cryptococcus albidus, Saccharomyces cerevisiae, Schizosaccharomyces octosporus) or molds (Aspergillus niger, Geotrichum candidum, Mucor haemalis) induced an increase in the mass of seminal vesicles and coagulating glands independent of whole body weight changes in mice.

Possible immunomodulation by low-level infection with Ostertagia ostertagi was studied in 4-month-old calves. Six groups of 4 calves each were subjected to the following regimes: group 1--nonparasitized controls; group 2--nonparasitized, but challenge exposed at day 64 with Brucella abortus strain 19 vaccine (BA) and at day 78 with IV administration of a soluble third-stage larval (L3) antigen preparation of O. ostertagi (OAG); group 3--nonparasitized, but challenge exposed at day 78 with 75 X 10(3) L3 of O ostertagi; group 4--continuously parasitized by weekly dosing with 30 X 10(3) L3 of O ostertagi; group 5--continuously parasitized by weekly dosing with 30 X 10(3) L3 of O ostertagi, then challenge exposed on day 64 with BA and on day 78 with IV inoculation of OAG; and group 6--continuously parasitized by weekly dosing with 30 X 10(3) L3 of O ostertagi, then challenge exposed on day 78 with 75 X 10(3) L3 of O ostertagi. Over the initial 10 weeks of the study, nonparasitized calves, (groups 1, 2, and 3) had higher body weight, blood lymphocyte (BL) response to phytohemagglutinin (PHA), and significantly (P less than 0.05) higher feed consumption and lymphocyte numbers, whereas parasitized calves (groups 4, 5, and 6) had higher BL responses to pokeweed mitogen (PWM) and significantly (P less than 0.05) higher neutrophil and eosinophil numbers, plasma pepsinogen (PP) values, and BL response to OAG. During the challenge-exposure period (weeks 10 through 13), group-5 calves had significantly (P less than 0.05) higher eosinophil numbers and PP values for week 11 (BA challenge exposure) and for week 13 (OAG challenge exposure) than did group-2 calves, but differences were not observed in BL responses to PHA, PWM, and OAG. Oral L3 challenge exposure at week 13 induced significantly (P less than 0.05) lower lymphocyte numbers, higher eosinophil numbers (P less than 0.05), and higher PP values, but lower BL response to PHA, PWM, and OAG in group-6, compared with group-3 calves. In continuously parasitized calves, comparison of IV OAG challenge exposure with oral L3 challenge exposure indicated that group-6 (L3) calves has significantly lower (P less than 0.05) lymphocyte numbers and higher PP values than did group-5 (OAG) calves. Results of ELISA revealed significantly (P less than 0.05) higher antibody titer to OAG in parasitized calves, compared with nonparasitized calves. Abomasal mucosal pathologic changes were most severe in the continuously parasitized calves. Calves of groups 4, 5, and 6 had thicker mucosae (edema), significantly (P less than 0.05) higher eosinophil numbers, and higher globule leukocyte and mast cell numbers in the fundic and pyloric regions than did calves of groups 1, 2, and 3. Calves of groups 4, 5, and 6 also had significantly (P less than 0.05) larger abomasal lymph node masses than did nonparasitized calves. In group-1 calves, nodes had the lowest mass. Differences were not observed among groups for lymphocyte responses to proliferative and suppressive assays performed on the abomasal lymph node lymphocytes.