A control trial of adult house flies, Musca domestica, was done with cyfluthrin mixed with piperonyl butoxide on a pig farm located in Narita-shi, Chiba Prefecture in September and October, 1988. One hundred house flies each collected on the farm were put into 13 cages, with one cage assigned as a non-treated control and the others treated: Two cages were sprayed with tap water in volumes of 50 ml/m² and 100ml/m², respectively. Four cages were sprayed with 100-, 200-, 400-, and 800-fold dilutions of a mixture, (at a ratio of 1: 5 calculated as active ingredients, ) of cyfluthrin 5%(W/W) emulsion and piperonyl butoxide in a volume of 50 ml/m². The other 4 cages were sprayed with 200-, 400-, 800-, and 1600-fold dilutions of the same mixture in a volume of 100 ml/m². To the remaining 2 cages, 200-and 400-fold dilutions of permethrin 4%(W/W) emulsion including a synergist were sprayed in volumes of 50 ml/m² and 100 ml/m², respectively As a result, cyfluthrin took a dose-dependent insecticidal effect, and the effect was almost the same regardless of the spray volume when the same amounts of active ingredient were sprayed. It was also observed that cyfluthrin developed higher efficacy than permethrin in the same amounts Based on the above results, 200-fold dilution of the mixture of cyfluthrin 5% emulsion and piperonyl butoxide was applied to house flies in the pig house in a volume of 50 ml/m², followed by an application 20 days later with 400-fold dilution in the same volume. Both applications, especially that with the 200-fold dilution, reduced the number of fllies greatly in the house.

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On a swine farm where sows had been maintained with leftover food, stillbirths and premature births appeared frequently and new-born piglets were found to have a weak constitution and hypodynamia. Histopathologically, a number of vacuoles of various sizes were noticed among myofibrils of skeletal muscles, and were stained red with oil red 0 and Nile blue. Some muscle fibres showed positive reaction to periodic acid Schiff staining, which disappeared after amylase digestion. Electron microscopy revealed numerous fatty droplets besides enlarged mitochondria in myofibrils, as well as increased levels of glycogen. In some cases, storage of lipid and glycogen was noted observed in hepatocytes and storage of lipid was noted in cardiac muscle. Virological and bacteriological examinations did not reveal any of microbes that are thought to cause abnormal parturition is swine (Aujeszky's disease virus, Japanese encephalitis virus, porcine parvovirus, Toxoplasma gondii, or Escherichia coli). Therefore, these cases of myopathy were thought to be induced by abnormal storage of neutral fat and glycogen and not by infectious diseases. On the other hand, biochemically, no decrease in serum free carnitine was observed in these piglets. According to the classification for human pathology, it was suggested that these cases may have been attributable to abnormalities in the mitochondrial electron transport system and not to systemic carnitine deficiency or mvooathic carnitine deficiency.

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Susceptibilities of Staphylococcus aureus strains isolated from healthy broilers against 18 antimicrobial agents including methicillin and new-quinolones were examined. Group A consisted of 100 strains which were freshly isolated from 35 (70%) out of 50 broilers in 1989 and group B included 32 strains isolated in 1981. A much greater number of highly resistant strains were detected in group A as compared to group B. Multi-resistant strains of S. aureus were also detected frequently in.group A. Antibiotic susceptibilities of recent isolates (group A) were remarkably reduced against TC, SA, SM, SPM, EM and OL. It was concluded that the use of large amounts of many types of drugs over a long period may induce a selective pressure for the increase and spread of drug-resistant strains.

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To investigate the existence of renal calculi in healthy dairy cattle, Holstein-Friesian cows submitted to gramineous feeding had their right kidneys scanned by ultrasonography. The animals were divided into three groups according to the method of housing: A, tie-stall, n=43; B, free-stall, n=41; and C, grazing, n=41.
In groups A, B and C, renal calculus-echoes in renal pelvises were detected in 93.0%(Type II, 44.2%; Type III, 48.8%), 82.9%(Type II, 14.6%; Type HE, 68.3%) and 63.4%(Type II, 7.3%; Type III, 56.1%), respectively. Groups B and C showed less renal pelvic calculi than group A.
These results strongly suggested that the formation of renal silica calculi is inevitable in cows fed with real grass, and that an adequate amount of exercise is a preventive method for clinical and subclinical urolithiasis of dairy cows.

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A total of 90 Bordetella bronchiseptica strains isolated from the nasal cavities of pigs in 1988 were examined for susceptibility to 13 antibacterial drugs. The rates of resistance to each doug were as follows: trimethoprime, 91.1%; sulfadimethoxine, 88.9%; trimethoprime+sulfadoxine (ST), 75.6%; ampicillin, 13.3%; streptomycin, 11.1%; chloramphenicol, 3.3%; nalidixic acid, 2.2%; and tetracycline, 1.1%. No strains showed resistance to kanamycin, gentamycin, colistin, rifampicin or enrofl oxacin.

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A nine-year, six-month old Shetland sheep dog was brought in suffering from rapidly failing vision. Examination of the eyes revealed numerous round, small bodies suspended in the vitreous body. The condition was diagnosed as asteroid hyalosis.
A few days later, bleeding into the vitreous body was observed in the right eye. In the left eye, there were severe retinal detachment and hemorrhage.
Histopathologically, arterioles of the bilateral fundi were found to have undergone a high degree of hyalinization, and arteriolar lumen had become narrow or blocked. In the kidney, extensive hyalinization of arterioles and glomerular sclerosis were seen. The hepatic interlobular arteries and splenic central arteries had also undergone hyalinization.
The above vascular changes consisting mainly of intimal hyalinization of arterioles in the systemic organs including the retina and choroidmembrane were diagnosed as arteriolosclerosis.
It was suspected that these ocular manifestations resulted from hemorrhage or exudation caused by retinal and choroidal arteriolosclerosis.

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In August 1989, a dairy cow showed positive tuberculin reaction in Niigata Prefecture.
Necropsy revealed skin lesions on the posterior region of the udder, approximately 50 cm under the vulva. The lesions consisted of multiple, cutaneous and subcutaneous nodules between 0.5 to 1 cm in diameter. Lesions were encapsulated by a thick connective tissue and the cut surface exuded a yellow brown pus. The supramammary lymph node was swollen with hemorrhage. Histologically, the skin lesions were composed of tuberculous granuloma. The center of the lesions showed necrosis, caseation and calcification, and epitheloid cells, Langhans-type giant cells, many lymphocytes and a small number of neutrophils were seen in the surrounding area. A few acid-fast bacilli were found in necrotic areas. The epitheloid cells and giant cells also infiltrated into the supramammary lymph node. No acid-fast bacilli were isolated from the lymph node.
Acid-fast bacilli belonging to RUNYON'S group IV were isolated from the skin lesions. Guinea pigs sensitized with isolated acid-fast bacilli showed a positive reaction against mammalian tuberculin.

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Bacteriological studies were performed on streptococci isolated from pigs with bacterial endocarditis during a period from 1985 to 1987.
Eighty-eight strains of streptococci were isolated from 86 (47.0%) of 183 pigs with endocarditis. Of the 86 cases, Lancefield's group C streptococci were isolated from 40 (S. equisimilis, 30; S. dysgalactiae, 3; and S. spp, 7), group D streptococci from 24 (S. suis II, 14; S. suis I, 7; and S. spp, 3) and other groups of streptococci from 22, respectively. The isolation rate of group C streptococci decreased yearly, namely, 64.3%(9/14) in 1985, 50.0%(21/42) in 1986 and 33.3%(10/30) in 1987, whereas that of group D streptococci increased from 7.1%(1/14) to 23.8%(10/42) and 43.3%(13/30), respectively. Thus, in 1987, the streptococci of group D were detected more frequently than those of group C.
The majority (83.3%, 20/24) of the strains of group D were detected from endocarditis lesions found on the left-side heart valves, whereas 35.0%(14/40) of the group C strains were isolated from the same side lesions. There was a significant difference (P<0.01) between the isolation rates of group C and D streptococci from the left-side endocarditis lesions. On the other hand, group C streptococci were isolated from an average of 4.4 out of five viscera and eight lymph nodes testetl for isolation, against 2.7 organs for group D streptococci. Similarly, 41.7%(10/24) of the group D streptococci were only detected in endocarditis lesions. These results suggest that streptococci of groups C and D have different abilities to cause endocarditis lesions on the left-side valves.

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