Urinary indices of renal function and damage were measured in 6 healthy, mature ewes over a 48-hour period. Endogenous creatinine clearance, total and fractional electrolyte excretion rates, protein excretion, urine volume, and urine gamma-glutamyltransferase and beta-glucuronidase activities were measured. Significant variations in the excretion rates of creatinine, electrolytes, and protein were not found between intervals within the 48-hour urine collection period. Total urinary electrolyte excretion rates were significantly (P < 0.001) correlated with fractional electrolyte excretion rates normalized for creatinine concentration; however, coefficient of determination was low.

Hematologic and serum biochemical values were determined in blood samples from 217 donkeys (Equus asinus). Donkeys were classified on the basis of size, sex, age, and whether they were domestic or feral. Parametric (mean +/- 2 SD) and nonparametric (2.5th to 97.5th percentile) reference ranges were calculated for each analyte. For all donkeys, 26 of 46 analytes significantly departed from gaussian distribution. Serum lactate dehydrogenase activity in miniature donkeys was higher than that in other donkeys. Differential leukocyte counts in feral donkeys differed from those in other types in ways that suggested that the former had smaller parasite loads or experienced greater stress. Erythrocyte, lymphocyte, and platelet counts and fibrinogen, glucose, inorganic phosphorus, and potassium concentrations decreased with age. Eosinophil counts, mean corpuscular volume, and plasma protein, serum protein, and serum globulin concentrations increased with age. Female donkeys had significantly (P < 0.05) higher mean corpuscular hemoglobin concentration and leukocyte and neutrophil counts than did male donkeys. Mean corpuscular hemoglobin increased with age, and females had higher values than did males of all age groups. An interaction between age and sex was observed for alkaline phosphatase activity, with a trend for decreased activity with age.

Effects of dietary aflatoxin (AF) and T-2 toxin, singly and in combination, were evaluated in growing crossbred (Yorkshire X Landrace X Hampshire) pigs. The experimental design consisted of 4 treatment groups of 6 barrows each fed diets containing 0 mg of AF and T-2/kg of feed (controls; group 1), 2.5 mg of AF/kg of feed (group 2), 10 mg of T-2/kg of feed (group 3), or 2.5 mg of AF plus 10 mg of T-2/kg of feed (AF + T-2; group 4) ad libitum for 28 days (7 to 11 weeks of age). Production performance, and serum biochemical, and hematologic evaluations were made weekly. Body weight and body weight gain were depressed by all toxin treatments, but the effect of AF and T-2 toxin in combination was less than additive. Liver and kidney weights, as a percentage of body weight, were increased by AF treatment, and heart weight, as a percentage of body weight, was increased by T-2 treatment. Treatment with T-2 toxin induced necrotizing contact dermatitis on the snout, buccal commissures, and prepuce. Consumption of AF resulted in increased serum activities of alkaline phosphatase, aspartate transaminase, cholinesterase, and gamma-glutamyltransferase, and decreased serum concentrations of urea nitrogen, cholesterol, albumin, total protein, calcium, potassium, magnesium, and phosphorus. Consumption of T-2 toxin resulted in increased serum triglyceride concentration and decreased serum iron concentration. Treatment with AF induced lower serum unsaturated iron-binding capacity and high RBC count, PCV, hemoglobin concentration, WBC count, and prothrombin time. Treatment with T-2 toxin induced microcytic hypochromic anemia, increased numbers of circulating metarubricytes and decreased absolute numbers of lymphocytes. Hepatocellular lesions in barrows of the AF and the AF plus T-2 groups (2 and 4, respectively) were compatible with aflatoxicosis. When fed in combination, each toxin appeared to have a sparing action on certain effects of the other, and the responses elicited were either additive or less than additive.

The immune receptor-mediated functions of bovine alveolar macrophages (AM) inoculated in vitro with bovine herpesvirus-1 (BHV-1) or parainfluenza-3 (PI-3) virus were tested in the presence or absence of virus-specific antiserum or pulmonary lavage fluids collected from calves 6 days after inoculation with BHV-1 or PI-3 virus. The Fc and C3b phagocytic indices of noninoculated AM, collected from 6- to 16-week-old calves, ranged from 75 to 87 and 59 to 64, respectively, and the binding indices ranged from 5 to 8 and 22 to 28, respectively. Infection of AM with either BHV-1 or PI-3 virus had no significant effect on receptor-mediated phagocytosis or binding, with the exception of a significant (P < 0.05) decrease, from 64 to 46, of the C3b phagocytic index of PI-3 virus-infected AM. The addition of lavage fluids, collected after BHV-1 or PI-3 virus infection, to AM infected with the respective virus caused a significant (P < 0.05) decrease in phagocytic indices with values for the Fc and C3b indices in BHV-1-infected AM decreasing from 81 to 49 and from 47 to 8, respectively, and those for the PI-3 virus-infected AM from 79 to 51 and from 46 to 15, respectively. The binding indices of virus-infected AM increased with the addition of viral lavage fluids, but the only significant (P < 0.05) increase was for C3b binding in PI-3 virus-infected cells, which increased from 33 to 56. Virus-specific serum added to AM infected with the respective virus also caused significant (P < 0.05) decreases in the Fc and C3b phagocytic indices, with those for BHV-1-infected AM decreasing from 81 to 24 and from 47 to 5, respectively, and those for PI-3 virus-infected AM from 79 to 23 and from 46 to 3, respectively. The Fc binding index significantly (P < 0.05) increased with the addition of virus-specific serum from 8 to 34 and from 10 to 42 in BHV-1 and PI-3 virus-infected AM, respectively. The C3b binding index of these AM also increased, but not significantly. Infection of AM with either BHV-1 or PI-3 virus had no significant effect on the phagocytosis of opsonized (OPZ) or nonopsonized (nonOPZ) Staphylococcus epidermidis (SE). The addition of lavage fluids, obtained after BHV-1 infection, to AM infected with BHV-1, significantly (P < 0.05) decreased the percentage of phagocytosis of OPZ-SE from 28 to 21 and had a similar, but less substantial effect, on the phagocytosis of nonOPZ-SE. Lavage fluids collected after PI-3 virus inoculation, added to PI-3 virus-infected AM did not have a notable effect on the phagocytosis of OPZ-SE, but did cause a significant (P < 0.05) decrease in the percentage of phagocytosis of nonOPZ-SE from 25 to 17. The addition of virus-specific serum to infected AM caused significant (P < 0.05) decreases in the percentage of phagocytosis of OPZ-SE and nonOPZ-SE, with the values in the BHV-1-infected AM going from 28 to 11 and 16 to 9, respectively, and in the PI-3-infected AM from 36 to 12 and 25 to 13, respectively. Alveolar macrophages infected with either BHV-1 or PI-3 virus, in the presence or absence of lavage fluids from virus-infected calves or virus-specific serum, killed ingested SE as readily as noninfected AM. On the basis of the findings of this study, we suggest, as with other virus infections, that products of the host antiviral immune response interact with AM infected with BHV-1 or PI-3 virus or cause impaired internalization of receptor-bound particles, resulting in impaired AM antimicrobial functions.

A field strain (87-8363) of bovid herpesvirus-4 (BHV-4) isolated from an aborted bovine fetus was used to inoculate pregnant rabbits. Eleven rabbits in midgestation were alloted to 4 groups consisting of 3 infected groups and 1 control group. Rabbits were inoculated with BHV-4 or mock-infected cell culture preparations via IV, intravaginal, and intrauterine routes. Mild vulvovaginitis and endometritis were observed after intravaginal and IV inoculation of BHV-4, whereas intrauterine inoculation of BHV-4 resulted in abortion of hemorrhagic fetuses and nonsuppurative endometritis. Virus was successfully isolated from organ explants of fetal tissues. Rabbits seroconverted 1 week after infection as detected by results of an indirect immunofluorescence assay.

The in vivo effects of a single prophylactic dose of recombinant bovine interferon (rBoIFN)-alphaI1 in calves with salmonellosis were investigated, using a Salmonella typhimurium infection model. Treatment with rBoIFN-alphaI1 reduced the degree of septicemia compared with that in control groups, and, in one experiment, using disease of reduced severity, body temperature was lower in treated calves than in controls.

Ten Holstein cows were fed a selenium-deficient (SeD) diet containing 0.04 mg of Se/kg of dry matter for 3 months before and throughout their first lactation. A selenium-supplemented (SeS) group of 10 cows was fed an additional 2 mg of Se/head/d to increase dietary Se concentration of the dry matter to approximately 0.14 mg/kg of body weight. An intracisternal challenge exposure of 40 to 60 colony-forming units (CFU) of Staphylococcus aureus was administered into 1 or 2 quarters of the udder of each trial cow at about the twenty-second week of lactation. Blood Se concentration (microgram/ml +/ - SEM) at the time of challenge exposure was 0.035 +/- 0.002 in SeD and 0.139 +/- 0.006 in SeS cows. Infections were established in 14/16 of the challenge-exposed quarters in SeD and 16/19 of the challenge-exposed quarters in SeS cows. The infection in 1 quarter of each Se group cleared without treatment by the end of the 8-week trial period. Log10 peak bacterial concentrations in milk from infected SeD quarters (5.04 +/- 0.25 CFU/ml) were higher (P < 0.05) than those of infected SeS quarters (4.40 +/- 0.12 CFU/ml). Log10 peak somatic cell count (SCC) in milk from infected SeD quarters (7.18 +/- 0.08 cells/ml) did not differ from that of SeS quarters (7.17 +/- 0.05 cells/ml). Peak bacterial concentrations were attained sooner (P < 0.05) in SeD quarters (9.5 +/- 4.0 days) than in SeS quarters (20.7 +/- 3.1 days). Similarly, peak SCC were reached earlier (P < 0.05) in SeD (4.3 +/- 1.1 days) than in SeS quarters (13.3 +/- 3.8 days). The Se groups did not differ significantly with respect to peak milk concentrations of bovine serum albumin or IgG1. Throughout the 8-week trial, the Se groups did not differ significantly in milk bacterial concentration, SCC, bovine serum albumin, or IgG1. Selenium status did not affect the percentage of challenge exposures resulting in infection, duration, or severity of experimentally induced S aureus mastitis.

Progesterone was administered IM to 6 adult anestrous bitches at a dosage of 2 mg/kg of body weight. Serum progesterone concentrations were measured prior to progesterone administration and for 72 hours thereafter. The serum progesterone concentration time data were analyzed by use of a pharmacokinetics modeling computer program. The mean (+/- SD) peak serum progesterone concentration (34.3 +/- 7.8 ng/ml) was reached at 1.8 +/- 0.2 hours after progesterone administration. The mean serum progesterone concentration was 6.9 +/- 1.4 ng/ml at 24 hours and 2.0 +/- 0.4 ng/ml at 48 hours after progesterone administration. By 72 hours after administration, mean serum progesterone concentration was 0.9 +/- 0.2 ng/ml, which was comparable to serum progesterone concentrations prior to injection. The mean half-life of the absorption phase was 0.5 hours (range, 0.3 to 0.7 hours). The mean half-life of elimination was 12.1 hours (range, 9.5 to 13.8 hours). By analysis of the data, it was established that a dosage of 3 mg/kg, when the hormone was given IM to dogs once a day, would maintain serum progesterone concentration > 10 ng/ml.

Serum samples obtained from 40,927 swine at various locations in North Carolina between Aug 1, 1987 and July 31, 1988, were tested for antibodies to Trichinella spiralis, using an ELISA based on a larval T spiralis excretory-secretory antigen. In the ELISA, samples were considered to have positive results if the optical density (OD) reading was equal to or 5 times greater than the mean OD value of 4 negative-control sera from trichina-free swine. Of the 40,927 serum samples tested, 154 (0.38%) were positive by ELISA; the rate for breeding swine was 0.35% (105/30,162), and the rate for cull swine was 0.45% (49/10,765). Of the 49 seropositive samples from cull swine, 11 were from out of the state, 22 had no identification, and 16 were known to originate from North Carolina. Seropositivity had a bimodally seasonal distribution, with peaks in March and September. There was no difference between the mean age of seropositive and seronegative swine, but males were at greater risk for seropositivity than were females. Pigs from lots with < 100 sera tested were at increased risk for seropositivity, as were pigs from the central coastal region of North Carolina.

The hemodynamic effects of high arterial carbon dioxide pressure (PaCO2) during anesthesia in horses were studied. Eight horses were anesthetized with xylazine, guaifenesin, and thiamylal, and were maintained with halothane in oxygen (end-tidal halothane concentration = 1.15%). Baseline data were collected while the horses were breathing spontaneously; then the horses were subjected to intermittent positive-pressure ventilation, and data were collected during normocapnia (PaCO2, 35 to 45 mm of Hg), moderate hypercapnia (PaCO2, 60 to 70 mm of Hg), and severe hypercapnia (PaCO2, 75 to 85 mm of Hg). Hypercapnia was induced by adding carbon dioxide to the inspired gas mixture. Moderate and severe hypercapnia were associated with significant (P < 0.05) increases in aortic blood pressure, left ventricular systolic pressure, cardiac output, stroke volume, maximal rate of increase and decrease in left ventricular pressure (positive and negative dP/dtmax, respectively), and median arterial blood flow, and decreased time constant for ventricular relaxation. These hemodynamic changes were accompanied by increased plasma epinephrine and norepinephrine concentrations. Administration of the beta-blocking drug, propranolol hydrochloride, markedly depressed the response to hypercapnia. This study confirmed that in horses, hypercapnia is associated with augmentation of cardiovascular function.