Reproductive performance of gilts and sows in ordinary piggeries was investigated with special reference to litter size, piglets weaned per litter, the cause of preweaning mortality and the incidence of diarrhea. Biochemical properties of Escherichia coli isolated from piglets with diarrhea were also determined. Of the 2,226 gilts and sows farrowed, average number of piglets born alived and weaned piglets per litter were 8.9 and 7.1, respectively, indicating that both gilts and sows lost more than 20% of all their piglets prior to weaning. The causes of preweaning mortality in order of prevalence were diarrhea (39.3%), pneumonia (20.0%), crushing (13.8%), starvation (11.0%) and born weak (10.3%). Incidence of 3 diarrheal syndromes of piglets, i.e. 1 week diarrhea, 3 week diarrhea and post-weaning diarrhea were 18.4%, 66.1% and 15.5%, respectively, showing that most farms were suffering from so called 'white scours' in piglets 14-28 days old.

In order to know the morphology and the function of the fat-storing cells (FSC) of the squirrels which were captured at the Pal-Gong mountain near Taegu, Korea [R.] in December, 1980 (Group A) and May, 1981 (Group B), respectively, light and electron microscopic observations were conducted on the liver of the squirrels. Light microscopically, the size of the lipid droplets in the FSC of group A was uniformly larger than those in the cells of group B, and number of the droplets in the FSC of group A was less than those in the cells of Group B. The distribution of the FSC of group A was mainly perilobular area while those of group B were centrolobular and midzonal areas. In this method, the FSC of the squirrels was similar to those cells of the hamsters. Electron microscopically, general morphology of the squirrel's FSC was accorded with those of the other mammals. However, the rough surfaced endoplasmic reticulum in the FSC of group B was more dilated than those in the cells of group A, and more lipid droplets and pinocytotic vesicles were observed in the FSC of group B than those in the cells of group A. From those evidences, it could be suggested that the metabolic rates in the FSC of the squirrels collected in the spring were higher than those in the cells of the animals collected in the winter.

In order to estimate the efficiency of feed added urea zeolite the experiment was carried on in vitro. The pH of all media added urea were inclined toward alkali, except 1% urea (included 99% zeolite) medium. The concentration of ammonia in all media added urea mixed zeolite was inversely proportional to added volume of zeolite; 1,349, 1,298, 1,164 and 786 micron g/ml in 40%, 20%, 10%, 5% and 1% urea media respectively for 30 minutes incubation, and the concentration of ammonia in all media was increased steadily as incubation time proceeded until 9 hours. The efficiency of adsorption of ammonia to zeolite of the feed added 40% urea mixture (dealing in the feed store) was hardly recognized. Accordingly, it is efficient to utilize the feed added 1-5% urea mixture, but it is of no practical use because they need much amount of zeolite.

The morphological and structural studies of Anisakinae larva has been carried out. The larva was collected from naturally infested eleven swine and from marine fishes, Somber joponicus. Anisakis larva found in the stomach wall and on the surface of mucosa were more or less degenerated. The reports on natural infestation of domestic animal with Anisakis type I larvae were two swine cases in Korea and Japan respectively. On the other hand two human cases of the larva were reported in Korea and more than one thousand cases in Japan. In Taiwan no reports of human and domestic animal cases could be found.

A series of experiments was designed and carried out to assess the variation of feeding performance of the adult female ticks of Haemaphysalis longicornis in the primary and repeated feeding trials on the same experimental host rabbit under laboratory conditions. It was concluded that an acquired immunity was indeed developed, that the feeding performance was reduced by repeated feeding of the ticks on the same host, and that it was not true economy to use a rabbit more than twice for the colonization of the tick H. longicornis.

An investigation on various causes of milking disturbances resulting from injuries and abnormalities of mammary system were made on 2,179 Holstein cows. To perform this investigation, 69 dairy farms of the suburban area of Seoul city, Gyeonggi-do and Chungnam provinces were randomly selected and subjected. Diagnosis was made by means of inspection and palpation of teat, insertion of teat canula, checking milk machines, anamneses and farm records. Dry off quarters were found in 158 quarters which turned out to be 1.8% of 8,716 quarters inspected. Among them 53.59% had one, 43.72% had two, 2.47% had three, and 0.22% had four supernumerary teats, respectively. Teat sphincter stenosis was 1.76% of 8.716 teats, loose sphincter was 0.89% of 8.716 teats and injured teat tip caused by over milking of milk machine was 2.63% of 8.716 teats.

Somatic, Envelope (O.K.) serogroups of 268 cultures of Escherichia coli isolated from piglets with colibacillary diarrhea were determined by the use of the simplified routine diagnostic procedures of Sojka. Of 268 cultures of Escherichia coli tested, 190 cultures were classified into 15 OK groups and the remaining 78 (29.1%) were untypable. The most frequently isolated enteropathogenic E. coli in order of prevalence were 0157:K'V17' (14.2%), 0149:K91, K88a, c (13.7%), 064:K'V142' (11.6%), 08:K87, K88a, b (10.5%) and 0141:K85a, b, K88a, b (7.9%).

It has long been believed for the presence of infectious coryza affecting serious economic loss of domestic poultry industry. However, the etiologic agent has not been isolated until quite recently. From 1979, several strains of Haemophylus-like organism were isolated from chickens with symptoms similar to infectious coryza, and their colonial morphology, growth requirement, biochemical properties and pathogenicity were assessed. In addition, serological properties of the isolate by cross hemaglutination inhibition test was also investigated. The results indicated that all the isolates were identified as Haemophilus gallinarum which had similar characteristics to the reference strains.

This experiment was undertaken to determine the causative agent of dermatophytosis that occurred in the 3 common seals and an elephant which were derived from the Tae-gu and Busan zoological gardens. Direct microscopic examination, culture and pathogenicity test were performed for the samples obtained from the skin lesions of the animals. The causative agent was identified as Trichophyton mentagrophytes exclusively in these cases, and the present report describes the first cases of the common seal and elephant as ringworm.

The immune response to bluetongue virus in sheep and cattle was studied by applying a newly developed indirect enzyme-linked immunosorbent assay (ELISA). Purified virus obtained by sucrose gradient centrifugation was used at a concentration of 0.01 optical density units (formula: see text) to coat individual wells (200 microliter) of a microtitration plate. Dilution of antigen was performed in 0.05 M carbonate buffer, pH 9.6, and adsorption lasted for at least 16 hours at 4 C. Coated plates retained their activity for 10 weeks when stored at 4 C. Sera recovered from experimentally infected sheep and cattle were tested together with known negative sera. A good correlation between results was obtained with the modified complement-fixation test and the ELISA; however, the ELISA proved to be more sensitive. The group specificity of the ELISA was proven by testing various type-specific sheep and cattle immune sera. The ELISA has potential for the detection of group-specific antibodies to bluetongue virus infection.