Enzyme-linked immunosorbent assay for the detection of bovine papillomavirus.

An enzyme-linked immunosorbent assay has been developed to detect and quantitate bovine papillomavirus in partially purified and in purified viral preparations, using rabbit antiserum against group-specific papillomavirus structural antigens and alkaline phosphatase-labeled affinity purified goat antibody to rabbit immunoglobulin G. Viral detection correlated well with negative-stain electron microscopy of the various preparations and peroxidase-antiperoxidase staining of paraffin sections of the original fibropapillomas. The technique is rapidly done and will detect minute amounts of viral protein (1 ng/ml).

Nicotinic acid and serum metabolite concentrations of lactating dairy cows fed supplemental niacin.

The effect of supplemental niacin on production and metabolite changes associated with early lactation were measured. Differences of milk production between treatments were not apparent, but serum nicotinic acid concentrations remained higher for those cows fed niacin (12 g/day). Changes of serum metabolites did occur when cows received a single oral dose of 12 or 120 g niacin. Significant alterations of nicotinic acid, free fatty acids, beta-hydroxybutyrate, blood urea nitrogen, serum glutamic-oxalacetic-transaminase, sodium, and chloride occurred within 24 h after initiation of treatment. These metabolites returned to basal concentrations within 60 h after administration.

Effect of an intramammary polyethylene device in primiparous dairy cows.

A sterilized polyethylene intramammary device (IMD) was inserted through the papillary duct into a front and a rear mammary quarter of 12 primiparous dairy cows, which were mastitis-free. This study was conducted during lactation from month 1 postpartum to completion (generally month 9). After the device was inserted, milk somatic cell counts (SCC) increased. Milk scc in the quarters fitted with IMD from foremilk, primary, and stripping samples were 5.2, 2.6, and 5.9 X 10(5) cells/ml, respectively. Comparable counts for control quarters were 2.1, 1.4, and 3.6 X 10(5) cells/ml. The SCC in foremilk from the quarters fitted with the device were 2 to 3 times greater than the counts in foremilk from control quarters during month 2 and subsequent months of lactation. The SCC were significantly increased in primary and stripping samples from quarters fitted with IMD; however, the SCC of 2.6 X 10(5) cells/ml in primary milk would not affect market milk quality. Milk production for the lactation was decreased (0.6 kg/quarter/day) in the quarters fitted with IMD in comparison with control quarters throughout the lactation. There were no differences in percentages of milk fat or protein between deviced and control quarters. Conductivity values were increased in foremilk and stripping samples, but not in primary samples, for the quarters with IMD. Bovine serum albumin concentrations were also increased.

Regional myocardial blood flow and coronary vascular reserve in unanesthetized young calves exposed to a simulated altitude of 3500 m for 8--10 weeks.

We determined regional myocardial blood flow (15-micrometer tracer microspheres) and hemodynamics in nine normal calves, seven calves with right ventricular (RV) hypertrophy induced by pulmonary artery banding (PAB) at sea level, and five calves exposed to simulated high altitude (HA) of 3,500 m (PB = 500 mm Hg) for 8--10 weeks. Progression of RV hypertrophy was very rapid in HA calves. RV weight:body weight ratio of 2.74 +/- 0.20 g/kg at 8--10 weeks of sojourn at HA significantly exceeded that in PAB calves (1.98 +/- 0.11 g/kg) 20 weeks post-banding. All calves were studied unanesthetized at sea level before (control) and during maximal coronary vasodilation (iv adenosine; 4 microM/kg per min). Normal and HA calves were also studied during acute hypoxemia (PaO2: 42 +/- 1 mm Hg) induced by administration of 12--13% O2 + N2 in the inhaled gas. RV myocardial blood flow was significantly increased only in PAB calves, whereas in HA calves it was similar to that in normal calves. Left ventricular (LV) mass and blood flow were identical in three groups of calves. Polycythemia did not occur in HA calves. Minimal coronary vascular resistance per unit weight of the hypertrophied RV was identical to that in the normal RV myocardium. This suggested that, despite very fast progression of RV hypertrophy in HA calves, functional cross-sectional area of the RV coronary vascular bed kept pace with the increase in cardiac mass. Minimal coronary vascular resistance per unit weight of the left ventricular myocardium was also identical in three groups of calves. This suggested that chronic hypoxemia by itself did not cause an increase in the functional cross-sectional area of the LV coronary vascular bed. Acute hypoxemia resulted in a significant increase in myocardial blood flow in all calves, but in HA calves, RV endo:epi perfusion ratio decreased below 1.00. Transmural RV myocardial blood flow and RV systolic pressure in HA calves during acute hypoxemia significantly exceeded that in normal calves.

Anthelmintic efficacy of ivermectin given intramuscularly in horses.

The anthelmintic activity of ivermectin was evaluated in 18 female horses with naturally acquired parasitic infections. Horses were treated once (IM) with vehicle only (n = 6), 200 microgram/kg of body weight (n = 6), and 300 microgram/kg (n = 6). Efficacy of both dosages of ivermectin was greater than 99% against Gasterophilus spp, 100% against Trichostrongylus axei, Habronema muscae, H majus, and Draschia megastoma, 98% to 99% against adult cyathostomes, 86% to 97% against 4th-stage cyathostomes, and 100% against adult large strongyles. Although ivermectin was incomplete in its activity against arterial stages of Strongylus vulgaris, it was effective against microfilariae of Onchocerca spp. Adverse local or systemic reactions were not observed due to treatment with ivermectin.

Repair of fractured capital femoral epiphysis in two sheep.

Fracture of the capital femoral epiphysis occurred in two sheep. Both fractures were repaired via open reduction and lag screw fixation. A craniolateral approach to the hip (modified Watson-Jones) afforded good exposure and allowed manipulation with minimal soft tissue trauma. Rigid internal fixation in each case resulted in good long-term results. It was concluded that repair of this type of fracture in sheep is feasible if the animal is valuable.