AN INFECTED HIP PROSTHESIS IN A DOG DIAGNOSED WITH A 99mTC-CIPROFLOXACIN (INFECTON) SCAN

This case report describes the use of the 99mTc-labeled radiopharmaceutical ciprofloxacin (Infecton) in a case of hip prosthesis loosening in a dog. Serial planar radiographs were not conclusive, and culture of the synovial fluid was negative. Antibiotic treatment did not result in improvement of the lameness. Scintigraphy was performed with 99-Tc-Infecton, a tracer claimed to be specific for infection. Antibiotic treatment was interrupted 6 weeks prior to the examination. Planar and tomographic images at 3 h and at 24 h postinjection showed increased activity along the acetabulum and the proximal femoral bone surrounding the femoral prosthesis, indicating focal infection. Bacteriology performed after removal of the implant revealed Pseudomonas aeruginosa.     

Reproductive lifetime of sows in relation to economy of production

In pig production substantial economic loss is involved in early culling of sows, due to low fertility, leg problems, etc. Data on 15 000 services from 85 commercial pig farms were analysed to quantify the importance of these losses. From the average cost price per weaner per litter and cumulative, a “sow remainder productive life value” has been calculated, indicating the economic loss when a sow has to be culled too early. Calculations for farms with low, average and high culling rates show substantial differences in economic results.     

Experimental production of congenital persistent swine fever infections: II. Effect on functions of the immune system

Twelve pregnant sows were infected at various stages of gestation with a low-virulent field strain of swine fever (SF) virus. The sows developed neutralizing antibody in serum, colostrum and milk.Only one pig had antibody to SF virus at birth. Twenty-three congenitally infected pigs developed a persistent viraemia. In the plasma samples of these pigs, neither antibodies nor virus-antibody complexes were detected after the disappearance of maternal antibodies.The persistently infected pigs showed a normal antibody response against sheep red blood cells, except in the terminal stage of disease. These observations indicate immunological tolerance to SF virus in these pigs. Immunological tolerance was also induced in pigs which had been infected in utero after the onset of immune competence.The lymphocyte response to phytohaemagglutinin seemed to be slightly depressed in the persistently infected pigs, whereas the response to pokeweed mitogen was comparable with that of control pigs.A clear, cell-mediated immune response to SF virus could not be demonstrated by the lymphocyte stimulation test.Three pigs that were born uninfected did not produce neutralizing antibody following natural exposure from in-contacts, whereas the littermates did. These pigs appeared to be sensitized when challenged with virulent SF virus.     

Accumulation of hyperparasites of Rhizoctonia solani by addition of live mycelium of R. solani to soil

Addition of live mycelium ofRhizoctonia solani to three slightly, acid sands collected in winter from a field after a previous potato crop resulted in accumulation of hyperparasites and less infestation of sprouts of infected seed potatoes. A similar effect was observed in alkaline marine sandy loam soils, but only after a second addition of live mycelium. The predominant hyperparasite in these experiments wasVerticillium biguttatum.     

Cardiotoxicity of the skin of the red-banded rubber frog, Phrynomerus bifasciatus (Smith 1847).

The skin of the red-banded rubber frog is said to secrete an unidentified toxin. Whole skin extract as well as HPLC fractions were tested for toxicity on viable, isolated cardiomyocytes. The skin extract and one of its fractions were shown to be cardiotoxic. Whole-cell clamping tests demonstrated that both extract and fraction interfered with the function of the potassium channels of the cardiomyocytes and that the toxic substance has an affinity for the IK, channels. Investigations are in progress to isolate and characterize the toxic substance.     

Changing adrenergic sensitivity of the caruncular arterial vasculature supplying the bovine placentome

With the advancement of gestation, blood flow increases preferentially to the caruncular bed of the gravid uterus in association with a decreasing sensitivity of the uterus to the vasoconstrictive effects of circulating catecholamines. This study directly compared the sensitivity of the caruncular artery (CA) of the isolated bovine placentome to phenylephrine (PE), a specific alpha 1-adrenergic receptor (AR) agonist, with that to norepinephrine (NE) and epinephrine (E), both of which are alpha 1-, alpha 2-, and beta-AR agonists, at two stages of gestation (140 to 170 d, mid-pregnant; 210 to 270 d, late pregnant). The CA of each placentome was perfused with oxygenated Krebs Ringer solution into which PE, NE or E were administered; increases in intra-arterial pressure were recorded. Further, NE content and numbers of alpha 1- and alpha 2-AR in the CA, intercaruncular arteries (ICA) and uterine arteries (UA) were quantitated. The CA from mid-pregnant cows exhibited greater (P less than .05) contractile responses to NE and E than did the CA from late pregnant cows, whereas responsiveness to PE remained constant. No difference in NE content, alpha 1-AR or alpha 2-AR numbers were observed in the UA, ICA or CA between mid-pregnant or late pregnant cows. Alpha 1-AR numbers were similar in CA, ICA and UA. However, CA contained threefold greater alpha 2-AR numbers than either the ICA or UA (50.2 +/- 6.1 vs 14.6 +/- 1.6 and 14.8 +/- 2.4 fmol/mg protein, respectively; P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Transplacental infection of porcine fetuses following experimental challenge inoculation with encephalomyocarditis virus.

Ten multiparous sows were inoculated between 46 and 50 days of gestation with a fetal swine isolate of encephalomyocarditis virus (EMCV) to investigate the ability of the virus to cause transplacental infection and fetal death. Four sows (group 1) were inoculated IM with EMCV MN-25 that had been passaged 4 times on baby hamster kidney-21 line cell monolayers. Two sows were euthanatized at postinoculation (PI) day 23, and the other 2 sows at PI day 44. An additional 6 sows (group 2) were inoculated IM with the same virus that had been passaged 5 additional times in pigs. Two sows were euthanatized at 14 days, and the remaining 4 sows at PI day 28. Clinical signs were not observed in any of the sows, whereas all sows seroconverted to EMCV. In group 1, only 2 of 50 fetuses were mummified. Virus was not recovered, although EMCV antibodies were detected in the 2 mummified fetuses. In group 2, the 2 sows that were euthanatized at PI day 14 had 26 normal fetuses and there was no evidence of fetal infection. However, in the 4 sows euthanatized at PI day 28, 20 of 48 fetuses were mummified, hemorrhagic, or edematous. Encephalomyocarditis virus was recovered from 21 of 48 fetuses. Transplacental infection and fetal deaths in pregnant sows was achieved following infection with EMCV passaged in pigs.