Recently, Japanese black beef farms have grown to a large scale and have become highly densified. Marbling beef is produced by supplying a large amount of concentrated feed from early in the life of the cattle. As a result, chronic febrile illnesses such as respiratory diseases, arthritis, and otitis media are increasing, and it is speculated that immunity may deteriorate due to the special feeding. In this study, we investigated the dynamics of blood fatty acids, which are attracting attention as an immunomodulatory nutrient, in 120 Japanese black female fattening cattle aged 9 to 30 months. The amount of linoleic acid (LA), an omega-6 fatty acid, increased significantly in the early middle stage of fattening and remained high until the finishing stage, but arachidonic acid (AA) was almost unchanged. Eicosapentaenoic acid (EPA), an omega-3 fatty acid, showed a significant decrease after the early middle stage of fattening, revealing an increase in the omega-6/omega-3 ratio.
A 150-day-old growing-finishing swine died of diarrhea, and the autopsy revealed hepatization of the lung and thickening of the ileocecal mucosa. Histopathological findings in the lungs included the accumulation of cellular debris and neutrophil infiltration in the bronchi and bronchioles. Alveolar spaces were occasionally filled with numerous neutrophils and abundant cellular debris. Multifocal necrosis of ileocecal mucosa with pseudomembrane was observed. Salmonella Typhimurium (ST) was isolated from the lung and intestinal content. Immunostaining with the ST antiserum revealed the ST antigens in lung and ileocecal lesions. These results suggest that ST was deeply involved in the pathogenesis of lung lesions in this case.
A total of 450 intestinal content specimens from the livestock were examined to survey the prevalence of Escherichia albertii among swine, cattle, and goat on Okinawa Island from July to December 2017. The results showed that 17 E. albertii isolates were obtained from 6.8% of the swine samples (17/250) from eight farms. All isolates harbored pathogenic associated genes (eae and cdt ) with identical biochemical properties, such as no acid production from lactose or sucrose. Pulsed-field gel electrophoresis (PFGE) showed several patterns of the isolates, suggesting genetic diversity among the swine isolates. Interestingly, four of six isolates obtained from a farm over a three-month period showed similar PFGE patterns. These results indicated that multiple genotypes of E. albertii may spread among swine directly or via the farm environment in Okinawa Island.
We classified commercial chickens as general broiler (General), Meigara-brand (Meigara), and Jidori-Japanese native (Jidori), and investigated contamination with Campylobacter spp. (C spp.) and Listeria spp. (L spp.). We isolated C spp. from 57 of 90 samples and C. jejuni from more than 50% of Jidori and Meigara chickens. We found that the amount of contamination with C. coli was less than half that of C. jejuni. L spp. was isolated from 49 of 65 samples. The segregation rates of both C spp. and L spp. were high for Jidori and Meigara, but low for General. We isolated both C spp. and L spp. from 43% of the samples. The number of samples in which only L spp. was isolated was three times greater than in the number of samples in which only C spp. was isolated. In terms of bacterial species, combined contamination with C. jejuni and L. innocua was most common. This study showed possible differences in the contamination level among Jidori, Meigara, and General chickens.