Effects of mycoplasmal pneumonia of swine (MPS) lung lesion‐selected Landrace pigs on MPS resistance and immune competence in three‐way crossbred pigs

To clarify the genetic influence of mycoplasmal pneumonia of swine (MPS) lesion‐selected Landrace (La) on MPS resistance and immune characteristics in three‐way crossbred pigs (LaWaDa), the LaWaDa pigs were compared with the non‐selected crossbred (LbWbDb) and purebred (La) pigs. The MPS lesion score in the three lines was as follows: La line < LaWaDa line < LbWbDb line, with significant differences among the lines. The proportions of myeloid cells and T cells were lower and higher, respectively, in the LaWaDa pigs compared with those in the other two lines. Messenger RNA (mRNA) expression of interleukin (IL)‐6, IL‐10, transforming growth factor‐β, and interferon‐γ in peripheral blood was significantly increased after vaccination in the La and LaWaDa lines. IL‐4 mRNA expression in the LaWaDa line was intermediate to the La and LbWbDb lines. Furthermore, principal component analysis for immune traits and MPS lesions was executed to clarify the characteristics of each pig line. These findings suggest that the immune responses in the three pig lines are genetically distinct and that MPS resistance and some immunity characteristics from the La line were transmitted to the three‐way crossbred pigs.     

Molecular epidemiology of <Emphasis Type="Italic">Pseudomonas syringae</Emphasis> pv. <Emphasis Type="Italic">syringae</Emphasis> strains isolated from barley and wheat infected with bacterial black node

A repetitive sequence-based (rep)-polymerase chain reaction (PCR) and inter-simple sequence repeat (ISSR)-PCR were used to molecular type Pseudomonas syringae pv. syringae (PSS) strains isolated from barley and wheat plants with bacterial black node symptoms grown in 22 different locations and six different seed-production districts in Japan. Eighteen genomic fingerprinting (GF) genotypes were obtained from the combined results of BOX-, REP-, and GTG₅-PCR, indicating that the PSS population in Japan has high genetic diversity. The result based on logistic regression indicated that the population of GF genotype A was significantly related to a seed-producing district and that the epidemic of PSS strains in fields originated mainly from seed infection. This study will be applicable to future studies of the molecular epidemiology of bacterial plant diseases that have multiple infection routes.     

Detection of serum antibodies in Eimeria tenella-infected chickens by enzyme linked immunosorbent assay (ELISA) with merozoite and oocyst antigens.

Soluble antigens prepared from sporulated oocytes and second generation merozoites of E. tenella were used for enzyme linked immunosorbent assay (ELISA) to investigate antibody in sera of two breeds of chickens, i.e. commercial broilers and SPF single comb white leghorn layers, which were experimentally infected with E. tenella. In broilers inoculated with oocysts at 15 days of age, ELISA values increased rapidly after day 19 post inoculation (PI) and reached the maximum lebel on days 29 and 32 PI against both merozoite and oocyst antigen. The values against merozoite antigen were significantly higher than those against oocyst antigen. In SPF layers infected at 15 days of age, the values increased gradually after 7 days PI. There were no significant differences between values against two antigens. Generally, the values in broilers tended to be higher than those in SPF layers, especially against merozoite antigen. In broilers inoculated with oocysts at 1 and 15 days of age, ELISA values increased rapidly and reached the maximum level on days 11 and 20 post second inoculation (PSI) against merozoite and oocyst antigens respectively and then the values against merozoite antigen decreased. The values against merozoite antigen were markedly higher than those against oocyst antigen. In SPF layers inoculated twice, the values reached the highest on day 11 PSI as in the case of broiler; however, after that day, the values against both antigens decreased. The sera reacted similarly against both antigens. The values against merozoite antigen were significantly higher in broilers than in SPF layers.(ABSTRACT TRUNCATED AT 250 WORDS)     

Prevalence of Listeria (spp.) in wild rats captured in the Kanto area of Japan.

In the Kanto area a total of 245 wild rats were captured. All rats captured in Ikebukuro (110 rats) and 9 out of 41 rats in Yokohama were Rattus rattus, and all other 126 rats were Rattus norvegicus. In Kashima and Ikebukuro, listeria was isolated from 28 rats (77.8%) and 27 rats (24.5%), respectively, but in the other 4 areas listeria was isolated from 0-7% rats. Listeria monocytogenes was isolated from 12 rats (10.9%) captured in Ikebukuro and 2 rats in Kashima and Numazu. The frequent isolation of L. monocytogenes in buildings suggests the possibility of R. rattus as a reservoir of L. monocytogenes and the continual environmental contamination in buildings by L. monocytogenes.     

Acute necrotising pancreatitis following grain overload in a donkey

A donkey developed abdominal discomfort and distension together with cardiovascular collapse and gastric reflux 24 to 36 hours after ingesting a large amount of poultry feed. Rectal findings prompted a laparotomy that identified extensive gastric dilation, an empty, atonic small intestine, dry colonic content and an easily corrected caecal displacement. These findings were not consistent with the severity of the signs, which were attributed to endotoxaemia. The donkey was euthanased during recovery. Necropsy revealed acute necrotising pancreatitis with massive gastric dilation and right dorsal colon impaction. The clinicopathological features of acute equine pancreatitis associated with grain overload are discussed.     

Seroepidemiological survey of lymphocytic choriomeningitis virus in wild house mouse (Mus musculus) in Yokohama Port, Japan.

From 1985 to 1989, a total of 129 mice was captured from 7 piers of Yokohama port. Of these, 9 (7.0%) were positive to lymphocytic choriomeningitis virus (LCMV) antigen in indirect fluorescence antibody test. Six out of 31 mice (19.4%) in 1985 and 3 out of 23 mice (13.0%) captured in 1986 were positive. All the mice (74) captured in 1988 and 1989 were negative. Although 7 out of 17 mice (41.2%) in Osanbashi-Shinko pier and 2 out of 23 (8.7%) in Honmoku pier were positive in 1985 and 1986, all mice captured in other piers were negative. This is the first report detecting LCMV antibody in wild house mice in Japan.     

Studies of waste tea garden soils (Part 1)1)

I. Introduction

In Uji district, Kyoto Pref., the most famous place of tea production in Japan, tea gardens, particularly the refined tea (Gyokuro and Matsucha) gardens, have been producing very low yields. Their features are poor, dotted with withered plants. Such tea gardens are named the waste tea gardens. ōsugi²⁾ and Yoshie³⁾ had made research on these phenomena since 1930 and ascribed them to some defects of soil properties.     

Mechanical and chemical constituents of water-stable aggregates of paddy soil with relationship to the aggregate size

Introduction

In previous papers¹,², a method for determining the water-stable aggregate in paddy soils has been reported. This method is based on the slaking disruption of air dried clod of soil in an excess of water. The aggregates thus obtained are truly stable in water and also stable against a gentle agitation in wet sieving operation. It is very interesting to study the cementing materials which stabilize the aggregates.